WO2024162127A1 - Electric power transmission device, electric power transmission method, and program - Google Patents

Abstract

An electric power transmission device (10) comprises: a transmission unit (13) that is capable of transmitting a first electromagnetic wave that is capable of supplying electric power to batteries that are connected to electric power-receiving devices (20), or a second electromagnetic wave that is capable of supplying electric power in a wider range than the first electromagnetic wave; and a transmission control unit (17B) that, when a first power-receiving device in which the electric power that is accumulated in the battery is equal to or less than a predetermined value has been detected among the electric power-receiving devices (20), transmits the second electromagnetic wave to a second electric power-receiving device in which the energy that is accumulated in the battery is not equal to or less than a predetermined value, said second electric power-receiving device being positioned in the vicinity of the first electric power-receiving device.

Description

Power transmission device, power transmission method, and program

This application relates to a power transmission device, a power transmission method, and a program.

Wireless power transmission is used to supply power to multiple power receiving devices. Patent Document 1 discloses a technology that estimates the amount of power required by a power receiving device based on the schedule information of a user who will use the device, and generates a power supply schedule based on the estimation result, power supply history, and power supply priority.

JP 2019-126199 A

　In conventional technology, the priority of the power transmission schedule is changed depending on the usage status of the power receiving device, but because the user registers the schedule for the power receiving device in advance, there is a possibility that the battery of the power receiving device will run out completely. Conventional wireless power transmission has room for improvement in terms of power supply to a power receiving device that has lost power.

The power transmission device according to one aspect has a transmission unit capable of transmitting a first electromagnetic wave, which is an electromagnetic wave capable of supplying power to a battery connected to a power receiving device, or a second electromagnetic wave capable of supplying power over a wider range than the first electromagnetic wave, and a power transmission control unit that, when it detects a first power receiving device among the power receiving devices whose battery has a predetermined amount of stored power or less, transmits the second electromagnetic wave to a second power receiving device located near the first power receiving device and whose battery has a stored energy that is not less than the predetermined amount.

The power transmission device according to one aspect has a transmission unit capable of transmitting a first electromagnetic wave, which is an electromagnetic wave capable of supplying power to a battery connected to a power receiving device, or a third electromagnetic wave capable of supplying power over a wider range than the first electromagnetic wave, and a power transmission control unit that, when a first power receiving device is detected among the power receiving devices, the power stored in the battery of which is equal to or less than a predetermined level, transmits the third electromagnetic wave radiated in all directions including the installation direction of the power receiving device to a second power receiving device located near the first power receiving device and in which the energy stored in the battery is not equal to or less than the predetermined level.

In one aspect of the power transmission method, a power transmission device has a transmitter capable of transmitting a first electromagnetic wave, which is an electromagnetic wave capable of supplying power to a battery connected to a power receiving device, or a second electromagnetic wave capable of supplying power over a wider range than the first electromagnetic wave, and when the power transmitting device detects a first power receiving device among the power receiving devices whose battery has stored power below a predetermined level, the transmitter transmits the second electromagnetic wave to a second power receiving device that is located near the first power receiving device and whose battery has stored energy that is not below the predetermined level.

In one aspect of the power transmission method, a power transmission device has a transmitter capable of transmitting a first electromagnetic wave, which is an electromagnetic wave capable of supplying power to a battery connected to a power receiving device, or a third electromagnetic wave, which is capable of supplying power over a wider range than the first electromagnetic wave, and when the power receiving device detects a first power receiving device among the power receiving devices whose battery has a predetermined amount of stored power or less, causes the transmitter to transmit the third electromagnetic wave, which is radiated in all directions including the installation direction of the power receiving device, to a second power receiving device that is located near the first power receiving device and whose battery has a stored energy that is not less than the predetermined amount.

The program according to one aspect causes a power transmitting device having a transmitter capable of transmitting a first electromagnetic wave, which is an electromagnetic wave capable of supplying power to a battery connected to a power receiving device, or a second electromagnetic wave capable of supplying power over a wider range than the first electromagnetic wave, to execute a step of causing the transmitter to transmit the second electromagnetic wave to a second power receiving device located near the first power receiving device and having an energy stored in the battery that is not less than the predetermined value, when a first power receiving device of the power receiving devices whose stored energy in the battery is less than a predetermined value is detected.

The program according to one aspect causes a power transmitting device having a transmitter capable of transmitting a first electromagnetic wave, which is an electromagnetic wave capable of supplying power to a battery connected to a power receiving device, or a third electromagnetic wave, which is capable of supplying power over a wider range than the first electromagnetic wave, to execute a step of causing the transmitter to transmit the third electromagnetic wave, which is radiated in all directions including the installation direction of the power receiving device, to a second power receiving device that is located near the first power receiving device and has an energy stored in the battery that is not below the predetermined level, when a first power receiving device of the power receiving devices is detected.

FIG. 1 is a diagram for explaining an overview of a system including a power transmitting device according to a first embodiment. FIG. 2 is a diagram for explaining an overview of a system including a power transmitting device according to the first embodiment. FIG. 3 is a diagram for explaining an abnormality in the system including the power transmitting device according to the first embodiment. FIG. 4 is a diagram for explaining an abnormality in the system including the power transmitting device according to the first embodiment. FIG. 5 is a diagram illustrating an example of a configuration of a power transmitting device according to the first embodiment. FIG. 6 is a diagram showing an example of the management data shown in FIG. FIG. 7 is a diagram showing an example of the schedule data shown in FIG. FIG. 8 is a diagram illustrating an example of the configuration of the power receiving device according to the first embodiment. FIG. 9 is a diagram for explaining a power supply schedule of the power transmitting device according to the first embodiment. FIG. 10 is a diagram for explaining an example of changing the beam width of the power transmitting device according to the first embodiment. FIG. 11 is a flowchart illustrating an example of a processing procedure executed by the power transmitting device according to the first embodiment. FIG. 12 is a diagram for explaining a power supply schedule of the power transmitting device according to the second embodiment. FIG. 13 is a diagram for explaining an example of omnidirectional radiation of the power transmitting device according to the second embodiment. FIG. 14 is a flowchart illustrating an example of a processing procedure executed by the power transmitting device according to the second embodiment.

Several embodiments for implementing the power transmission device, power transmission method, program, etc., according to the present application will be described in detail with reference to the drawings. Note that the present invention is not limited to the following description. Furthermore, the components in the following description include those that a person skilled in the art can easily imagine, those that are substantially the same, and those that are within the so-called equivalent range. In the following description, similar components may be given the same reference numerals. Furthermore, duplicate descriptions may be omitted.

(Embodiment 1)
1 and 2 are diagrams for explaining an overview of a system including a power transmission device according to the first embodiment. The system 1 shown in FIG. 1 and FIG. 2 includes, for example, a wireless power transmission system capable of microwave transmission type (space transmission type) wireless power transmission. Wireless power transmission is a mechanism that allows power to be transmitted without using, for example, a cable or a plug. The microwave transmission type system 1 uses electromagnetic waves (microwaves) as energy transmission. The electromagnetic waves are included in radio waves. The frequency of the electromagnetic waves used in the microwave transmission type system 1 can be used in a plurality of frequency bands, and in Japan, for example, includes the 920 MHz band, the 2.4 GHz band, the 5.7 GHz band, and the like. In this embodiment, the system 1 makes it possible to simultaneously improve the power supply efficiency appropriate to the situation and ensure safety. The system 1 can be applied to, for example, space solar power generation. In the wireless power transmission system according to the embodiment of the present disclosure, the frequency band of the electromagnetic waves used is not limited to the microwaves described above, and electromagnetic waves with a wide wavelength range from several meters to several pm may be used as the wavelength of the electromagnetic waves.

In this embodiment, the system 1 is described as having four power receiving devices 20A, 20B, 20C, and 20D, but the number is not limited to this. In the following description, when there is no need to distinguish between the power receiving devices 20A, 20B, 20C, and 20D, they will be referred to as "power receiving devices 20" and duplicate descriptions will be omitted.

The system 1 includes a power transmission device 10, a plurality of power receiving devices 20, and a management device 30. The power transmission device 10 and the plurality of power receiving devices 20 are configured to be able to communicate wirelessly. The power transmission device 10 and the management device 30 are configured to be able to communicate wirelessly or via a wire. In this embodiment, the system 1 is described as including the management device 30, but the system may not include the management device 30, or the functions of the management device 30 may be incorporated into the power transmission device 10.

The power transmission device 10 is a device that wirelessly transmits power in the system 1. The power transmission device 10 is a device capable of transmitting electromagnetic waves for power supply. Transmitting electromagnetic waves for power supply includes radiating the electromagnetic waves from an antenna. The power transmission device 10 can use multiple-input multiple-output (MIMO) antenna technology. In MIMO, antenna elements at each end of a communication circuit are combined to minimize errors and optimize data speed. In the following description, the power transmission device 10 may be referred to as "own device."

The multiple power receiving devices 20 in the system 1 are powered devices that receive electromagnetic waves for power supply from the power transmitting device 10 to obtain power. The power receiving devices 20 include, for example, smartphones, tablet terminals, IoT (Internet of Things) sensors, machine tools, notebook personal computers, drones, electric cars, electric bicycles, game consoles, etc. The system 1 may be capable of managing the use of electromagnetic waves by time division, frequency division, etc., to prevent interference between electromagnetic waves.

The power receiving device 20 may be a stationary power receiving device that is not moving, or a mobile power receiving device. Even if the power receiving device 20 is stopped, the pilot signal may search the surrounding environment (such as the room conditions) to transmit the transmission radio waves. When the power receiving device 20 is stopped, the transmission radio waves may not be transmitted to a position previously recognized by the power receiving device 20, but may be transmitted to another power receiving device that transmits a pilot signal.

The power receiving device 20 may notify the power transmitting device 10 and the management device 30 of a low remaining battery charge. The present disclosure can be applied to cases where the power receiving device 20 is unable to notify of a low remaining battery charge. For example, there are cases where the power receiving device 20 is unable to notify of a low remaining battery charge, such as when the power receiving device 20 consumes power suddenly.

The management device 30 is a server device that provides a function for managing multiple power receiving devices 20. The management device 30 can be realized, for example, by a personal computer, a tablet terminal, a smartphone, etc. The management device 30 is configured to be able to communicate with the power transmitting device 10, and can transmit and receive various information between the management device 30 and the power transmitting device 10.

In the example shown in FIG. 1, system 1 includes power receiving device 20A, power receiving device 20B, power receiving device 20C, and power receiving device 20D installed at different positions in an installation area such as a factory or facility. Management device 30 has a function of managing management data related to power receiving device 20A, power receiving device 20B, power receiving device 20C, and power receiving device 20D for each device. The management data includes information such as the position of power receiving device 20, the remaining battery power, and the power consumption of applications used.

Each of the power receiving device 20A, the power receiving device 20B, the power receiving device 20C, and the power receiving device 20D periodically transmits a prescribed signal 1000 determined between the power receiving device 10 and the power transmitting device 10. The prescribed signal 1000 includes, for example, a beacon, a pilot signal, etc. The power receiving device 20 can transmit the prescribed signal 1000 at different times during a transmission time period, for example. The power receiving device 20 can transmit the prescribed signal 1000 to which various information such as identification information, remaining battery capacity information, and power consumption information is added. The power consumption information includes the power consumption of the entire device and the power consumption of each application. The power receiving device 20 can transmit the prescribed signal 1000 by emitting electromagnetic waves including the prescribed signal 1000. The prescribed signal 1000 may include any other information such as the position of the power receiving device 20 and information on the application being used.

When the power transmission device 10 receives the regulated signal 1000, it has the function of estimating the position of the power receiving device 20 based on the regulated signal 1000. The power transmission device 10 estimates the position (direction) of the power receiving device 20 from the power transmission device 10 based on the received electromagnetic wave intensity of the electromagnetic wave that received the regulated signal 1000. The power transmission device 10 calculates a transmission weight (weighting coefficient) for the estimated position of the power receiving device 20. The power transmission device 10 transmits information about the power receiving device 20 indicated by the regulated signal 1000 to the management device 30, and thereby associates the information with the power receiving device 20 and registers it in the management device 30.

As shown in FIG. 2, the power transmitting device 10 performs directivity control by multiplying the antenna by a weighting coefficient, and transmits electromagnetic waves 2000 including a transmission signal for power supply sequentially to each of the power receiving devices 20A, 20B, 20C, and 20D. Transmitting the electromagnetic waves 2000 includes, for example, the antenna radiating electromagnetic waves for power supply. Directivity control means, for example, controlling the relationship between the radiation direction and radiation intensity of the electromagnetic waves. If the frequency of the specified signal 1000 and the transmission signal is the same and the time fluctuation of the propagation path is ignored, the characteristics of the multiple paths from the power transmitting device 10 to the power receiving device 20 are the same as the characteristics from the power receiving device 20 to the power transmitting device 10. As a result, the electromagnetic waves 2000 transmitted from the power transmitting device 10 have a radiation pattern (beam) that utilizes not only the paths toward the power receiving device 20, but also paths toward a direction different from the power receiving device 20. The power transmission device 10 sequentially performs directivity control to form electromagnetic waves 2000 to each of the power receiving devices 20A, 20B, 20C, and 20D, and transmits power.

3 and 4 are diagrams for explaining an abnormality in the system 1 including the power transmission device 10 according to the first embodiment. As shown in FIG. 3, in the system 1, when a battery shortage occurs in the power receiving device 20D, the power transmission device 10 is unable to receive the prescribed signal 1000 from the power receiving device 20D. Battery shortage includes, for example, a state in which the remaining battery charge of the power receiving device 20 is below a threshold, there is no remaining battery charge, or the prescribed signal 1000 cannot be transmitted. In this case, the power transmission device 10 can receive the prescribed signal 1000 from each of the power receiving devices 20A, 20B, and 20C, but cannot receive the prescribed signal 1000 from the power receiving device 20D. The power transmission device 10 detects the power receiving device 20D, which does not receive the periodic prescribed signal 1000, as a first power receiving device with a low battery.

Situations in which the battery is lost in the power receiving device 20 include when the power that can be supplied from the power transmitting device 10 is smaller than the power consumption of the power receiving device 20, when the power supply per power receiving device 20 decreases due to an increase in the number of power receiving devices 20, when the power that can be supplied to other power receiving devices 20 decreases due to the appearance of a power receiving device 20 with a high priority for power supply, when a power receiving device 20 moves away and the power supply to that power receiving device 20 decreases, and when the power consumption of the power receiving device 20 suddenly increases (for example, when frequent communication becomes necessary).

As shown in FIG. 4, the power transmission device 10 performs directivity control by multiplying the antenna by a weighting coefficient, and sequentially transmits electromagnetic waves 2000 including a transmission signal for power supply to each of the power receiving devices 20A, 20B, and 20C, and does not transmit electromagnetic waves 2000 to the power receiving device 20D. As a result, the system 1 is in a state in which the power transmission device 10 does not supply power to the power receiving device 20D that has lost power. Therefore, in this embodiment, the system 1 provides a power transmission device 10 and the like that is capable of supplying power to a power receiving device 20 that has lost power.

[Configuration of power transmission device according to embodiment 1]
Fig. 5 is a diagram illustrating an example of a configuration of the power transmitting device 10 according to the first embodiment. Fig. 6 is a diagram illustrating an example of management data illustrated in Fig. 5. Fig. 7 is a diagram illustrating an example of schedule data illustrated in Fig. 5.

As shown in FIG. 5, the power transmission device 10 includes an antenna 11, a transmission signal generation unit 12, a transmission unit 13, a reception unit 14, an estimation unit 15, a storage unit 16, and a control unit 17. The control unit 17 is electrically connected to the transmission signal generation unit 12, the transmission unit 13, the reception unit 14, the estimation unit 15, the storage unit 16, etc. In this embodiment, for the sake of simplicity, the power transmission device 10 will be described with respect to a case in which the antenna 11 includes four antenna elements 11A, but the number of antenna elements 11A is not limited to this.

The antenna 11 is configured to allow for directional control (beamforming). The antenna 11 is an antenna array equipped with multiple antenna elements 11A. For example, the multiple antenna elements 11A each radiate the same electromagnetic wave, and by adjusting the phase and power intensity of each, the antenna 11 is configured to be able to strengthen the electromagnetic wave in a specific direction and weaken it by canceling each other out in another direction. The antenna 11 radiates electromagnetic waves 2000 including a transmission signal, and receives electromagnetic waves including a signal from the power receiving device 20. The antenna 11 supplies the received signal to the receiving unit 14. The main lobe of the antenna 11 is the direction in which the radiation of the electromagnetic waves 2000 is maximum.

The transmission signal generating unit 12 generates a transmission signal for power supply by converting the current to be transmitted to the power receiving device 20 into electromagnetic waves. The transmission signal is a signal for transmitting electromagnetic waves 2000 capable of supplying power. The transmission signal generating unit 12 generates a transmission signal by converting a current from a power source into electromagnetic waves of a transmission frequency. Power sources include, for example, a commercial power source, a DC power source, a battery, etc. The transmission signal generating unit 12 supplies the generated transmission signal to the transmitting unit 13.

The transmitting unit 13 is electrically connected to the multiple antenna elements 11A of the antenna 11. The transmitting unit 13 transmits electromagnetic waves 2000 by radiating the electromagnetic waves 2000, which include a transmission signal for power supply, from the antenna 11. The transmitting unit 13 radiates the electromagnetic waves 2000 in a specific direction from the multiple antenna elements 11A by applying weights corresponding to beams that can be formed by the multiple antenna elements 11A. The transmitting unit 13 applies weights instructed by the control unit 17 to the multiple antenna elements 11A. The transmitting unit 13 transmits the communication signal by radiating radio waves including the communication signal from the antenna 11. The transmitting unit 13 transmits the communication signal to the management device 30, other communication devices, etc.

The receiving unit 14 is electrically connected to the multiple antenna elements 11A of the antenna 11, the estimation unit 15, etc. The receiving unit 14 extracts a received signal from the electromagnetic waves received from the power receiving device 20 via the antenna 11. The received signal includes, for example, the above-mentioned specified signal 1000, etc. The receiving unit 14 supplies the extracted received signal to the estimation unit 15, the control unit 17, etc.

The estimation unit 15 estimates the electromagnetic wave propagation environment from the known specified signal 1000 received from the power receiving device 20. The electromagnetic wave propagation environment includes, for example, the space in which electromagnetic waves propagate between the power transmitting device 10 and the power receiving device 20. The estimation unit 15 estimates, for example, the state of electromagnetic wave propagation in space. The state of electromagnetic wave propagation includes, for example, a state in which it is possible to identify an environment in which direct waves are dominant, a multipath-rich environment in which reflected waves occur, etc. The estimation unit 15 estimates a reception response vector (terminal arrival direction) from the received signal. The estimation unit 15 estimates the reception response vector, for example, by comparing the known specified signal 1000 included in the received signal with a known reference signal. The estimation unit 15 estimates the propagation environment, terminal arrival direction, distance, etc., using, for example, the reception level, sensitivity, reception response vector, reference propagation model, machine learning program, etc. of the specified signal 1000 in order to grasp the state of electromagnetic wave propagation in space. The estimation unit 15 estimates the position of the power receiving device 20 based on the strength of the radio wave including the specified signal 10000 received from the power receiving device 20 and the estimated terminal arrival direction. The estimation unit 15 supplies the estimation result based on the specified signal 1000 to the control unit 17.

The storage unit 16 can store programs and data. The storage unit 16 may include any non-transient storage medium, such as a semiconductor storage medium and a magnetic storage medium. The storage unit 16 may include a combination of a storage medium, such as a memory card, an optical disk, or a magneto-optical disk, and a storage medium reader. The storage unit 16 may include a storage device used as a temporary storage area, such as a RAM.

The storage unit 16 can store a program 16A, weight data 16B, management data 16C, schedule data 16D, etc. The program 16A can provide functions for implementing processes related to various operations of the power transmission device 10. The program 16A can provide various functions related to wireless power transmission. The weight data 16B has data indicating, for example, multiple weights (weighting coefficients) for adjusting the amplitude and phase of signals radiated from the multiple antenna elements 11A of the antenna 11 for each of multiple directivity patterns. The weight data 16B has, for example, data indicating a combination of multiple antenna elements 11A corresponding to a directivity pattern. The weight data 16B includes, for example, data indicating weights obtained by estimating the time fluctuation of the reception response vector, focusing on the fact that the weight vector (weighting coefficient vector) can be uniquely expressed by the reception response vector in each antenna element 11A.

Management data 16C is data used to manage multiple power receiving devices 20. For example, as shown in FIG. 6, management data 16C has items such as identification information, location information, power consumption information, and history information. The identification information item is set with information for identifying power receiving device 20A, power receiving device 20B, power receiving device 20C, and power receiving device 20D. The location information item is set with information indicating the position P1 of power receiving device 20A, the position P2 of power receiving device 20B, the position P3 of power receiving device 20C, and the position P4 of power receiving device 20D. The location information includes, for example, information such as the position of the power receiving device 20 and the direction from the power transmitting device 10 (terminal arrival direction). The power consumption information item is set with information indicating the power W1 of power receiving device 20A, the power W2 of power receiving device 20B, the power W3 of power receiving device 20C, and the power W4 of power receiving device 20D. In this embodiment, the power consumption information includes, for example, the total power consumption of the power receiving device 20, the power consumption of each application installed in the power receiving device 20, etc. The history information items include information indicating the history H1 of the power receiving device 20A, the history H2 of the power receiving device 20B, the history H3 of the power receiving device 20C, and the history H4 of the power receiving device 20D. The history information includes, for example, the reception history of the specified signal 1000 from the power receiving device 20, the history of the remaining battery capacity of the power receiving device 20, etc.

Schedule data 16D has data showing the power supply schedule of power transmitting device 10 for power receiving device 20A, power receiving device 20B, power receiving device 20C, and power receiving device 20D. For example, as shown in FIG. 7, schedule data 16D shows a time-division power supply schedule SC for power transmission to power receiving device 20A, power receiving device 20B, power receiving device 20C, and power receiving device 20D. In FIG. 7, the horizontal direction shows time. In the example shown in FIG. 7, schedule data 16D shows power supply schedule SC for two periods for power receiving device 20A, power receiving device 20B, power receiving device 20C, and power receiving device 20D. Schedule data 16D shows power supply schedule SC for power transmission TA of power receiving device 20A, power transmission TB of power receiving device 20B, power transmission TC of power receiving device 20C, and power transmission TD of power receiving device 20D. Power transmission TA, power transmission TB, power transmission TC, and power transmission TD indicate, for example, the transmission time, amount of power, etc., that are set according to the power consumption of the power receiving device 20, the remaining battery charge, etc.

As shown in FIG. 5, the control unit 17 includes one or more arithmetic devices. Examples of arithmetic devices include, but are not limited to, a CPU (Central Processing Unit), a SoC (System-on-a-Chip), an MCU (Micro Control Unit), an FPGA (Field-Programmable Gate Array), and a coprocessor. The control unit 17 realizes processing related to various operations of the power transmission device 10 by having the arithmetic device execute the program 16A. The control unit 17 may realize at least a portion of the functions provided by the program 16A using a dedicated IC (Integrated Circuit).

When the control unit 17 detects a first power receiving device among the multiple power receiving devices 20 that is low on battery power, the control unit 17 executes the program 16A to change the second electromagnetic waves that are supplied to a second power receiving device in the vicinity of the first power receiving device so that the first power receiving device and the second power receiving device can be powered, and transmits the changed second electromagnetic waves to the transmission unit 13. The control unit 17 controls the directionality of the electromagnetic waves 2000 based on the estimation result of the estimation unit 15.

For example, the control unit 17 has functional units of a detection unit 17A and a power transmission control unit 17B. The control unit 17 executes the program 16A to function as functional units such as the detection unit 17A and the power transmission control unit 17B.

The detection unit 17A detects a power receiving device 20 that cannot receive the specified signal 1000 as a first power receiving device with a low battery. When the detection unit 17A is no longer able to receive the specified signal 1000 from a power receiving device 20 that was able to receive the specified signal 1000 during the previous transmission time period, the detection unit 17A detects the power receiving device 20 as a first power receiving device with a low battery. When the detection unit 17A is unable to receive the specified signal 1000 from the power receiving device 20 for a predetermined determination time, the detection unit 17A detects the power receiving device 20 as a first power receiving device with a low battery. This allows the power transmitting device 10 to wait for an obstacle to pass or move between the power transmitting device 10 and the power receiving device 20, thereby improving the accuracy of detecting a low battery.

When the detection unit 17A detects a first power receiving device with a low battery among the multiple power receiving devices 20, it detects a second power receiving device in the vicinity of the first power receiving device. The detection unit 17A detects a second power receiving device close to the position, direction, etc. of the first power receiving device based on the position information and detection conditions in the management data 16C. The detection conditions include, for example, conditions for determining that the first power receiving device is in the vicinity based on the position, direction, etc. of the first power receiving device. The detection conditions include, for example, conditions such as the range of the direction of the second power receiving device relative to the direction of the first power receiving device from the device itself, and a threshold or range for comparing with the distance between the first power receiving device and the second power receiving device. The detection unit 17A detects, for example, the power receiving device 20 closest to the first power receiving device as the second power receiving device.

The power transmission control unit 17B applies a weight to the transmission unit 13 based on the weight data 16B, which directs the main lobe of the transmission signal in the direction of the power receiving device 20 to which power is to be transmitted, thereby radiating electromagnetic waves 2000 in a specific direction from the multiple antenna elements 11A. Based on the schedule data 16D, the power transmission control unit 17B controls the transmission signal generation unit 12 to generate a transmission signal corresponding to power transmission and to transmit it from the transmission unit 13. Based on the power supply schedule SC for the multiple power receiving devices 20, the power transmission control unit 17B controls the transmission of the first electromagnetic wave or the second electromagnetic wave to the multiple power receiving devices 20. The first electromagnetic wave is an electromagnetic wave used to supply power to the multiple power receiving devices 20. The second electromagnetic wave is an electromagnetic wave used to supply power to a second power receiving device in the vicinity of the first power receiving device.

When the power transmission control unit 17B detects a first power receiving device out of the multiple power receiving devices 20 that is low on battery power, it modifies the second electromagnetic waves that are to be used to supply power to a second power receiving device near the first power receiving device so that the first power receiving device and the second power receiving device can be powered, and causes the transmission unit 13 to transmit the power. The power transmission control unit 17B modifies the second electromagnetic waves that are to be used to supply power to the second power receiving device detected by the detection unit 17A so that the first power receiving device and the second power receiving device can be powered, and causes the transmission unit 13 to transmit the power. The power transmission control unit 17B causes the transmission unit 13 to transmit, as the second electromagnetic wave, an electromagnetic wave with a wider beam width than the first electromagnetic wave.

The power transmission control unit 17B generates or changes the power supply schedule SC based on the specified signal 1000 received from the power receiving device 20. When the power transmission control unit 17B receives the specified signal 1000 from multiple power receiving devices 20, it generates power supply schedules SC for the multiple power receiving devices 20 and sets them in the schedule data 16D. When the power transmission control unit 17B detects a first power receiving device with a low battery among the multiple power receiving devices 20, it changes the power supply schedule SC to transmit the second electromagnetic waves. When the power transmission control unit 17B detects a first power receiving device with a low battery among the multiple power receiving devices 20, it stops the power supply schedule SC for the first power receiving device and then causes the transmitter 13 to transmit the second electromagnetic waves to the second power receiving device. The power transmission control unit 17B causes the transmitter 13 to transmit the second electromagnetic waves during the time period of the power supply schedule SC for the first power receiving device with a low battery. After causing the transmission unit 13 to transmit the second electromagnetic waves, the power transmission control unit 17B ends the transmission of the second electromagnetic waves when it receives a regulation signal 1000 from the first power receiving device.

The above describes an example of the functional configuration of the power transmission device 10 according to this embodiment. Note that the above configuration described using FIG. 5 is merely an example, and the functional configuration of the power transmission device 10 according to this embodiment is not limited to this example. The functional configuration of the power transmission device 10 according to this embodiment can be flexibly modified according to the specifications and operation.

[Configuration of power receiving device according to embodiment 1]
Fig. 8 is a diagram illustrating an example of the configuration of the power receiving device 20 according to embodiment 1. As illustrated in Fig. 8, the power receiving device 20 includes an antenna 21, a generating unit 22, a converting unit 23, and a battery 24.

The antenna 21 is electrically connected to the generating unit 22 and the converting unit 23. The antenna 21, for example, emits electromagnetic waves including the specified signal 1000 and receives electromagnetic waves including a signal from the power transmitting device 10. The antenna 21 supplies the received electromagnetic waves to the converting unit 23.

The generating unit 22 generates the prescribed signal 1000 and causes the antenna 21 to radiate electromagnetic waves including the prescribed signal 1000. The generating unit 22 generates the prescribed signal 1000 at a predetermined timing. The predetermined timing includes, for example, a timing after a certain time has elapsed, a specified timing, etc. The generating unit 22 may be configured to generate a signal different from the prescribed signal 1000. In this embodiment, the generating unit 22 generates the prescribed signal 1000 to which various information such as identification information, remaining charge information of the battery 24, power consumption information, etc. has been added.

The conversion unit 23 is electrically connected to the battery 24. The conversion unit 23 converts the electromagnetic waves received by the antenna 21 into a direct current, and uses this direct current to charge the battery 24. The conversion unit 23 converts the electromagnetic waves into a direct current, for example, using a known rectifier circuit.

The battery 24 is electrically connected to the conversion unit 23. The battery 24 includes a rechargeable battery. The battery 24 includes, for example, a battery compatible with Qi (an international standard for wireless power supply). The battery 24 can supply stored power to each part in the power receiving device 20 that requires power.

The above describes an example of the functional configuration of the power receiving device 20 according to this embodiment. Note that the above configuration described using FIG. 8 is merely an example, and the functional configuration of the power receiving device 20 according to this embodiment is not limited to this example. The functional configuration of the power receiving device 20 according to this embodiment can be flexibly modified according to the specifications and operation.

In this embodiment, the power receiving device 20 generates and transmits the regulation signal 1000 to which various information such as identification information, remaining charge information of the battery 24, and power consumption information is added, but this is not limited to the above. For example, the power receiving device 20 may be configured to add a position detection means such as a GPS (Global Positioning System) receiver to its configuration and add position information indicating the current position to the regulation signal 1000.

[Example of power supply operation of power transmission device according to embodiment 1]
Fig. 9 is a diagram for explaining a power supply schedule of the power transmitting device 10 according to the embodiment 1. Fig. 10 is a diagram for explaining an example of changing the beam width of the power transmitting device 10 according to the embodiment 1. In Fig. 9 and Fig. 10, it is assumed that the power transmitting device 10 transmits electromagnetic waves 2000 for power transmission to the four power receiving devices 20A, 20B, 20C, and 20D described above.

When the power transmission device 10 receives the specified signal 1000 from the power receiving device 20A, the power receiving device 20B, the power receiving device 20C, and the power receiving device 20D, the power transmission device 10 sequentially transmits the electromagnetic waves 2000 for power transmission based on the power supply schedule SC1 shown in FIG. 9. In detail, the power transmission device 10 transmits the electromagnetic waves 2000 including a transmission signal corresponding to the power transmission TA, transmits the electromagnetic waves 2000 including a transmission signal corresponding to the power transmission TB, transmits the electromagnetic waves 2000 including a transmission signal corresponding to the power transmission TC, and transmits the electromagnetic waves 2000 including a transmission signal corresponding to the power transmission TD. In this way, the power transmission device 10 performs wireless power transmission using the electromagnetic waves 2000 with the amount of power appropriate for each of the power receiving devices 20A, 20B, 20C, and 20D.

After that, power receiving device 20D experiences a battery shortage and is unable to transmit the prescribed signal 1000 to power transmitting device 10. In this case, power transmitting device 10 can receive the prescribed signal 1000 from each of power receiving device 20A, power receiving device 20B, and power receiving device 20C, but cannot receive the prescribed signal 1000 from power receiving device 20D, and therefore detects power receiving device 20D as a first power receiving device with a low battery. Of power receiving device 20A, power receiving device 20B, and power receiving device 20C, power transmitting device 10 detects power receiving device 20C, which is in the vicinity of power receiving device 20D, as a second power receiving device. Power transmitting device 10 changes power supply schedule SC1 to power supply schedule SC2, which does not transmit power to power receiving device 20D. In this embodiment, the power supply schedule SC2 has the power transmission TD portion of the power supply schedule SC1 left blank, but the time may be shortened or the power transmission time of the power receiving device 20A, the power receiving device 20B, and the power receiving device 20C may be lengthened.

The power transmission device 10 sequentially transmits electromagnetic waves 2000 for power transmission corresponding to the power receiving device 20A, the power receiving device 20B, and the power receiving device 20C based on the changed power supply schedule SC2. As a result, the power transmission device 10 does not transmit the electromagnetic waves 2000 in the direction of the power receiving device 20D, so safety can be ensured if a person or animal is present in that direction.

If the power transmission device 10 continues to be unable to receive the specified signal 1000 from the power receiving device 20D, it changes the power supply schedule SC2 to a power supply schedule SC3 in which the beam width of the electromagnetic waves to the power receiving device 20C, which is the second power receiving device, is changed and power is transmitted. Based on the changed power supply schedule SC3, the power transmission device 10 transmits electromagnetic waves 2000 for power transmission to the power receiving device 20A and the power receiving device 20B. Then, as shown in FIG. 10, the power transmission device 10 changes the beam width 2100 of the electromagnetic waves 2000 to the power receiving device 20C, and transmits the electromagnetic waves 2000 including a transmission signal corresponding to the power transmission TCD. In this embodiment, the power transmitting device 10 shifts the direction of the main lobe of the electromagnetic wave 2000 from the power receiving device 20C to the power receiving device 20D and widens the beam width 2100 in the direction of the power receiving device 20D, so that the electromagnetic wave 2000 intended for the power receiving device 20C can also be received by the power receiving device 20D. As a result, the power transmitting device 10 makes the electromagnetic wave 2000 intended for the power receiving device 20C arrive at the power receiving device 20D as well, so that the power receiving device 20D with a low battery can receive the electromagnetic wave 2000 and charge the battery 24.

When the power receiving device 20D charges the battery 24, it transmits a prescribed signal 1000 to the power transmitting device 10. Then, when the power transmitting device 10 receives the prescribed signal 1000 from the power receiving device 20D, it determines that the battery shortage of the power receiving device 20D has been resolved, and changes the power supply schedule SC3 to the normal power supply schedule SC1. After that, when the power transmitting device 10 receives the prescribed signal 1000 from the power receiving device 20A, the power receiving device 20B, the power receiving device 20C, and the power receiving device 20D, it sequentially transmits electromagnetic waves 2000 for power transmission based on the power supply schedule SC1.

As described above, when the periodic regulation signal 1000 from the power receiving device 20D disappears, the power transmitting device 10 transmits power to all of the power receiving devices 20A, 20B, and 20C other than the power receiving device 20D using electromagnetic waves 2000 (first electromagnetic waves). The power transmitting device 10 can then transmit power to the power receiving device 20C in the vicinity of the power receiving device 20D using electromagnetic waves 2000 (second electromagnetic waves) that widen the beam width 2100 of the first electromagnetic waves. This allows the power transmitting device 10 to charge a power receiving device 20 with a low battery using the electromagnetic waves 2000 sent to the other power receiving devices 20, thereby improving the power supply to a power receiving device 20 that has lost power.

The power transmission device 10 also modifies the second electromagnetic waves to be supplied to the detected second power receiving device so that the first power receiving device and the second power receiving device can be supplied with power, and transmits the modified second electromagnetic waves from the transmission unit 13. As a result, the power transmission device 10 uses the electromagnetic waves 2000 to transmit power to the power receiving device 20 that is not low on battery power, eliminating the need to transmit the electromagnetic waves 2000 to the power receiving device 20 that is low on battery power, thereby improving safety.

The power transmitting device 10 also detects the power receiving device 20 that cannot receive the regulated signal 1000 as a first power receiving device with a low battery. This allows the power transmitting device 10 to detect the power receiving device 20 with a low battery in the communication configuration by using the last received regulated signal 1000, thereby suppressing an increase in the device configuration.

In addition, when the power transmitting device 10 detects a power receiving device 20 with a low battery, it transmits, as the second electromagnetic wave, electromagnetic waves 2000 with a wider beam width 2100 than the first electromagnetic wave. This allows the power transmitting device 10 to increase the possibility of charging the power receiving device 20 with a low battery by using the electromagnetic waves 2000 with a wider beam width 2100, thereby improving the power supply to the power receiving device 20 that has lost power.

The power transmitting device 10 also detects a second power receiving device in the vicinity of the first power receiving device based on the specified signal 1000 last received from the first power receiving device. For example, if the battery is low, the power receiving device 20 is likely to remain in that position. This allows the power transmitting device 10 to transmit electromagnetic waves 2000 with a wider beam width 2100 to the second power receiving device, thereby increasing the possibility of charging the power receiving device 20 with a low battery, thereby improving the power supply to the power receiving device 20 that has lost power.

The power transmission device 10 also controls the transmission of the first electromagnetic wave or the second electromagnetic wave to the multiple power receiving devices 20 based on the power supply schedule SC for the multiple power receiving devices 20. This allows the power transmission device 10 to transmit electromagnetic waves 2000 with a widened beam width 2100 to the second power receiving device using the schedules of the first power receiving device and the second power receiving device, thereby further increasing the possibility of charging a power receiving device 20 with a low battery.

The power transmission device 10 also generates or changes a power supply schedule based on the prescribed signal 1000 received from the power receiving device 20. This allows the power transmission device 10 to generate or change a schedule for the power receiving device 20 that has received the prescribed signal 1000, making it possible to supply power to multiple power receiving devices 20 according to a schedule suited to the installation environment. Furthermore, when the power transmission device 10 detects a power receiving device 20 with a low battery, it can temporarily change the schedule to supply power to the power receiving device 20 and also supply power to the power receiving device 20 with a low battery.

The power transmission device 10 also causes the transmitter 13 to transmit the second electromagnetic waves during the time period (one cycle) of the power supply schedule of the first power receiving device that is low on battery power. This allows the power transmission device 10 to minimize changes to the power supply schedule even when transmitting electromagnetic waves 2000 to multiple power receiving devices 20, thereby minimizing the impact on the other power receiving devices 20 and allowing the power receiving device that is low on battery power to be supplied.

Furthermore, after transmitting the second electromagnetic waves to the transmitter 13, if the power transmission device 10 receives a prescribed signal 1000 from the first power receiving device, the power transmission device 10 ends the transmission of the second electromagnetic waves. This allows the power transmission device 10 to confirm that the battery shortage in the first power receiving device has been relieved and to return to the normal schedule, making maintenance unnecessary.

In addition, if the power transmitting device 10 continues to be unable to receive the prescribed signal 1000 from the power receiving device 20D despite the electromagnetic waves 2000 intended for the power receiving device 20C also reaching the power receiving device 20D, the power transmitting device 10 notifies the power receiving device 20D that it has determined to have a low battery. For example, the power transmitting device 10 generates notification information indicating the power receiving device 20D that it has determined to have a low battery, and transmits it to the management device 300, thereby causing the notification information to be output to an administrator, etc. In this way, the power transmitting device 10 can contribute to promptly dealing with the power receiving device 20 by making the power receiving device 20 that has a low battery among multiple power receiving devices 20 aware of the power receiving device 20.

In the example shown in FIG. 9, the power transmission device 10 uses the power supply schedule SC1, the power supply schedule SC2, and the power supply schedule SC3 in this order, but this is not limiting. For example, when the power transmission device 10 detects that the first power receiving device has a low battery, the power transmission device 10 may be configured to transmit the second electromagnetic waves based on the power supply schedule SC3 without using the power supply schedule SC2.

[Processing Procedure of Power Transmission Device According to First Embodiment]
Fig. 11 is a flowchart showing an example of a processing procedure executed by the power transmission device 10 according to the embodiment. The processing procedure shown in Fig. 11 is realized by the control unit 17 of the power transmission device 10 executing the program 16A. The processing procedure shown in Fig. 11 is repeatedly executed by the control unit 17.

As shown in FIG. 11, the control unit 17 of the power transmitting device 10 receives the specified signal 1000 from the multiple power receiving devices 20 via the receiving unit 14 (step S101). For example, the control unit 17 acquires the specified signal 1000 from the electromagnetic waves received by the antenna 11 during the transmission time period. When the processing of step S101 ends, the control unit 17 advances the processing to step S102.

The control unit 17 determines whether or not the prescribed signal 1000 has been received from all power receiving devices 20 (step S102). For example, the control unit 17 determines that the prescribed signal 1000 has been received from all power receiving devices 20 when the identification information indicated by all the received prescribed signals 1000 matches the identification information in the management data 16C. When the control unit 17 determines that the prescribed signal 1000 has been received from all power receiving devices 20 (Yes in step S102), the process proceeds to step S103.

The control unit 17 controls power transmission to the multiple power receiving devices 20 based on the power supply schedule SC (step S103). For example, for each power receiving device 20 indicated by the power supply schedule SC, the control unit 17 sets a weight corresponding to the power receiving device 20 in the transmission unit 13, and causes the antenna 11 to radiate electromagnetic waves 2000 including the transmission signal generated by the transmission signal generation unit 12. As a result, the transmission unit 13 sequentially transmits electromagnetic waves 2000 for supplying power to the multiple power receiving devices 20. When the process of step S103 ends, the control unit 17 ends the processing procedure shown in FIG. 11.

If the control unit 17 determines that the specified signal 1000 has not been received from all power receiving devices 20 (No in step S102), the control unit 17 proceeds to step S104. The control unit 17 detects a first power receiving device with a low battery (step S104). For example, the control unit 17 detects, among the multiple power receiving devices 20, a power receiving device 20 that has not received the specified signal 1000 during the transmission time period as the first power receiving device. When the control unit 17 completes the process of step S104, the control unit 17 proceeds to step S105.

The control unit 17 detects a second power receiving device in the vicinity of the first power receiving device (step S105). For example, based on the position information of the management data 16C, the control unit 17 detects the power receiving device 20 closest to the first power receiving device detected in step S104 as the second power receiving device. When the process of step S105 ends, the control unit 17 advances the process to step S106.

The control unit 17 changes the second electromagnetic waves to be supplied to the second power receiving device so that the first power receiving device and the second power receiving device can be supplied with power (step S106). For example, the control unit 17 changes the beam width 2100 of the second electromagnetic waves based on the positional relationship between the first power receiving device and the second power receiving device so that the second electromagnetic waves to be transmitted to the second power receiving device can receive power from the first power receiving device. In order to supply power to the first power receiving device and the second power receiving device with the second electromagnetic waves, the control unit 17 changes the power supply schedule SC so that the time for which the second electromagnetic waves are emitted is longer than before the change. When the control unit 17 changes the power supply schedule SC based on the change in the second electromagnetic waves, the process proceeds to step S107.

The control unit 17 controls power transmission to the multiple power supply devices based on the changed power supply schedule SC (step S107). For example, the control unit 17 sets a weight corresponding to each power receiving device 20 indicated by the changed power supply schedule SC in the transmission unit 13, and causes the antenna 11 to radiate electromagnetic waves 2000 including the transmission signal generated by the transmission signal generation unit 12. As a result, the transmission unit 13 transmits second electromagnetic waves with a widened beam width 2100 to the first power receiving device and the second power receiving device, and sequentially transmits electromagnetic waves 2000 corresponding to the power receiving device 20 to each of the other power receiving devices 20. When the process of step S107 is completed, the control unit 17 advances the process to step S108.

The control unit 17 determines whether or not the specified signal 1000 has been received from the first power receiving device (step S108). For example, the control unit 17 determines that the specified signal 1000 has been received from the first power receiving device when the identification information of the specified signal 1000 received by the receiving unit 14 matches the identification information of the first power receiving device. When the control unit 17 determines that the specified signal 1000 has been received from the first power receiving device (Yes in step S108), the process proceeds to step S109.

The control unit 17 restores the second electromagnetic wave and the power supply schedule SC that have been changed (step S109). For example, the control unit 17 restores the beam width 2100 of the second electromagnetic wave and the power supply schedule SC that have been changed in step S106 to the beam width 2100 and the power supply schedule SC before the change. When the processing of step S109 ends, the control unit 17 ends the processing procedure shown in FIG. 11.

If the control unit 17 determines that the specified signal 1000 has not been received from the first power receiving device (No in step S108), the control unit 17 advances the process to step S110. The control unit 17 determines whether or not the determination time has elapsed (step S110). For example, the control unit 17 determines that the determination time has elapsed when the time since the second electromagnetic wave was transmitted in step S107 is equal to or longer than the determination time set in step S107. If the control unit 17 determines that the determination time has not elapsed (No in step S110), the control unit 17 returns the process to step S108 already described and continues the process. If the control unit 17 determines that the determination time has elapsed (Yes in step S110), the control unit 17 advances the process to step S111.

The control unit 17 executes a notification process for the detected power receiving device 20 with a low battery (step S111). The notification process includes, for example, a process of generating notification information for notifying the detected power receiving device 20 with a low battery, and a process of transmitting the notification information to the management device 300, etc. The control unit 17 executes the notification process to notify the management device 300, etc., of the detected power receiving device 20 with a low battery. When the process of step S111 ends, the control unit 17 ends the processing procedure shown in FIG. 11.

(Embodiment 2)
The system 1 according to the second embodiment includes, as in the first embodiment, a power transmission device 10, a plurality of power receiving devices 20, and a management device 30. The power transmission device 10 and the power receiving devices 20 have the same basic configuration as the power transmission device 10 and the power receiving devices 20 according to the first embodiment. In the following description, configurations different from the first embodiment will be described.

The power transmission device 10 includes the antenna 11, transmission signal generation unit 12, transmission unit 13, reception unit 14, estimation unit 15, storage unit 16, and control unit 17 shown in FIG. 5 above. The control unit 17 has functional units of a detection unit 17A and a power transmission control unit 17B. In the power transmission device 10 according to the second embodiment, the power transmission control unit 17B has the following functions:

When the power transmission control unit 17B detects a first power receiving device with a low battery among the multiple power receiving devices 20, it causes the transmission unit 13 to transmit a third electromagnetic wave radiated in all directions including the installation direction of the first power receiving device. When the detection unit 17A detects a first power receiving device, the power transmission control unit 17B causes the transmission unit 13 to transmit a third electromagnetic wave radiated in all directions including the installation direction of the first power receiving device. The power transmission control unit 17B controls the transmission of the first electromagnetic wave or the third electromagnetic wave to the multiple power receiving devices 20 based on the power supply schedule SC for the multiple power receiving devices 20. When the power transmission control unit 17B detects a first power receiving device with a low battery among the multiple power receiving devices 20, it stops the power supply schedule SC for the first power receiving device and then causes the transmission unit 13 to transmit the third electromagnetic wave radiated in all directions including the installation direction of the first power receiving device. The power transmission control unit 17B causes the transmission unit 13 to transmit the third electromagnetic wave during the time period of the power supply schedule SC of the first power receiving device with a low battery.

In this way, in the present disclosure, even if the power receiving device 20 moves, the beam width to the nearby power receiving device 20 can be widened to supply power to the power receiving device 20 with a low battery, so as to affect as little as possible other power receiving devices 20 that are targets of power supply. Also, if the power receiving device 20 that has lost its battery moves, it is not possible to identify its location from the power receiving device 20 using a pilot signal or the like. In response to this, a camera is installed on the power transmitting side, the power receiving device 20 that is the target of power supply is recognized within the range visible from the camera, the position of the power receiving device 20 that has lost its battery is identified by the camera, and the beam width to the nearby power receiving device 20 that is the target of power supply is widened, so that the power receiving device 20 with the lost battery can be supplied with power even if it has moved.

In addition, in this disclosure, when a camera cannot be installed, or when a power receiving device 20 that has lost its battery moves outside the range of the camera even if a camera is installed, the beam width is widened based on the information registered in the management device 30 (recording device) to widen the range in which radio waves are emitted, making it possible to supply radio wave energy to the power receiving device 20 even in areas that cannot be seen by the camera.

In the present disclosure, when supplying power to a power receiving device 20 that has lost its battery by widening the beam width, a time limit (e.g., 10 seconds) can be set, and the beam width can be widened sequentially for the multiple power receiving devices 20 that are currently being powered. Also, in the present disclosure, control is performed with priority given to minimizing overall impact, and if there is no response from the power receiving device 20 that has lost its battery within the time limit, the power receiving device 20 for which the beam width is to be widened is switched in sequence, and if there is still no response from the power receiving device 20 that has lost its battery, power is transmitted using the time interval for omnidirectional radiation.

[Example of power supply operation of power transmission device according to embodiment 2]
Fig. 12 is a diagram for explaining a power supply schedule SC of the power transmission device 10 according to embodiment 2. Fig. 13 is a diagram for explaining an example of omnidirectional radiation of the power transmission device 10 according to embodiment 2. In Fig. 12 and Fig. 13, it is assumed that the power transmission device 10 transmits electromagnetic waves 2000 for power transmission to the above-mentioned four power receiving devices 20A, 20B, 20C, and 20D.

The omnidirectional radiation of the present disclosure may include electromagnetic waves emitted in a spherical state from the power transmission device 10. In other words, the omnidirectional radiation of the present disclosure may include electromagnetic waves that are spherically symmetric with respect to a three-dimensional transmission origin, or electromagnetic waves that are axially symmetric with respect to a specific z-axis direction that passes through a two-dimensional transmission origin. When the electromagnetic waves that are spherically symmetric are expressed in spherical coordinates with mutually perpendicular axes being the x-axis, y-axis, and z-axis, the distance from the origin being r, the angle with the z-axis being θ, and the angle with the x-axis in the xy plane being φ, the electromagnetic wave E at coordinates (r, θ, φ) may be electromagnetic wave E(r) that depends only on r.

Furthermore, the omnidirectional radiation disclosed herein may be radiation in which the beamforming direction of the transmitted electromagnetic waves changes from 0 to 2π in the φ direction in a predetermined period T, where the mutually perpendicular axes are the x-axis, y-axis, and z-axis, the distance from the origin is r, the angle with the z-axis is θ, and the angle with the x-axis in the xy plane is φ. In this case, the beamforming direction of the electromagnetic waves may change discretely or continuously from 0 to 2π in the φ direction in the predetermined period T.

When the power transmission device 10 receives the specified signal 1000 from the power receiving device 20A, the power receiving device 20B, the power receiving device 20C, and the power receiving device 20D, the power transmission device 10 sequentially transmits the electromagnetic waves 2000 for power transmission based on the power supply schedule SC1 shown in FIG. 12. As a result, the power transmission device 10 performs wireless power transmission using the electromagnetic waves 2000 with the amount of power appropriate for each of the power receiving devices 20A, the power receiving device 20B, the power receiving device 20C, and the power receiving device 20D.

After that, power receiving device 20D experiences a battery shortage and is unable to transmit the prescribed signal 1000 to power transmitting device 10. In this case, power transmitting device 10 can receive the prescribed signal 1000 from each of power receiving device 20A, power receiving device 20B, and power receiving device 20C, but cannot receive the prescribed signal 1000 from power receiving device 20D, and therefore detects power receiving device 20D as a first power receiving device with a low battery. Of power receiving device 20A, power receiving device 20B, and power receiving device 20C, power transmitting device 10 detects power receiving device 20C, which is in the vicinity of power receiving device 20D, as a second power receiving device. Power transmitting device 10 changes power supply schedule SC1 to power supply schedule SC2, which does not transmit power to power receiving device 20D. The power transmission device 10 sequentially transmits electromagnetic waves 2000 for power transmission corresponding to the power receiving device 20A, the power receiving device 20B, and the power receiving device 20C based on the changed power supply schedule SC2.

If the power transmission device 10 continues to be unable to receive the specified signal 1000 from the power receiving device 20D, the power transmission device 10 changes the power supply schedule SC2 to a power supply schedule SC4 in which a third electromagnetic wave with omnidirectional radiation is transmitted to the power receiving device 20C, which is the second power receiving device. Based on the changed power supply schedule SC4, the power transmission device 10 sequentially transmits electromagnetic waves 2000 for power transmission to the power receiving device 20A, the power receiving device 20B, and the power receiving device 20C. In the power supply schedule SC4, the portion of the power transmission TD in the power supply schedule SC1 has been changed to a schedule for omnidirectional radiation. Therefore, the power transmission device 10 performs control to transmit the electromagnetic wave with omnidirectional radiation as follows.

As shown in FIG. 13, the power transmission device 10 transmits a third electromagnetic wave 2300 radiated in all directions including the installation direction 2200 of the power receiving device 20D with a low battery. The installation direction 2200 includes, for example, the direction from the device itself to the power receiving device 20D with a low battery. The installation direction 2200 is estimated based on the position information of the power receiving device 20D indicated by the management data 16C. In this embodiment, the third electromagnetic wave 2300 is omnidirectional from the device itself to all of the multiple power receiving devices 20, but is not limited to this. The third electromagnetic wave 2300 may be, for example, an electromagnetic wave radiated in all directions, 360 degrees from the device itself as the center. The power transmission device 10 transmits the third electromagnetic wave 2300 radiated in all directions by, for example, increasing the power of a specific antenna element in the antenna 11. As a result, the power transmitting device 10 causes the third electromagnetic wave 2300 to reach the power receiving device 20D as well, so that the power receiving device 20D with a low battery can receive the electromagnetic wave 2000 and charge the battery 24.

When the power receiving device 20D charges the battery 24, it transmits a prescribed signal 1000 to the power transmitting device 10. Then, when the power transmitting device 10 receives the prescribed signal 1000 from the power receiving device 20D, it determines that the battery shortage of the power receiving device 20D has been resolved, and changes the power supply schedule SC3 to the normal power supply schedule SC1. After that, when the power transmitting device 10 receives the prescribed signal 1000 from the power receiving device 20A, the power receiving device 20B, the power receiving device 20C, and the power receiving device 20D, it sequentially transmits electromagnetic waves 2000 for power transmission based on the power supply schedule SC1.

As a result, when the periodic prescribed signal 1000 from the power receiving device 20D disappears, the power transmitting device 10 can transmit power to all of the power receiving devices 20A, 20B, 20C, and 20D using the third electromagnetic waves 2300. This allows the power transmitting device 10 to charge the power receiving device 20 that is running low on battery power using the third electromagnetic waves 2300 radiated in all directions, thereby improving the power supply to the power receiving device 20 that has lost power.

In addition, when the power transmission device 10 detects the first power receiving device, it transmits the third electromagnetic wave 2300 radiated in all directions including the installation direction 2200 of the first power receiving device to the transmitter 13. As a result, by using the third electromagnetic wave 2300 radiated in all directions, the power transmission device 10 can improve the possibility of charging the power receiving device 20 that has run out of battery power, and can improve the power supply to the power receiving device 20 that has lost power.

The power transmission device 10 also controls the transmission of the first electromagnetic wave or the third electromagnetic wave 2300 to the multiple power receiving devices 20 based on the power supply schedule SC for the multiple power receiving devices 20. This allows the power transmission device 10 to transmit the third electromagnetic wave 2300 radiated in all directions to the second power receiving device using the schedules of the first power receiving device and the second power receiving device, thereby further increasing the possibility of charging a power receiving device 20 with a low battery.

The power transmission device 10 also causes the transmitter 13 to transmit the third electromagnetic wave 2300 during the time period (one cycle) of the power supply schedule of the first power receiving device with a low battery. This allows the power transmission device 10 to minimize changes to the power supply schedule even when transmitting electromagnetic waves 2000 to multiple power receiving devices 20, thereby minimizing the impact on the other power receiving devices 20 and allowing the power receiving device 20 with a low battery to be powered.

Furthermore, after transmitting the third electromagnetic wave 2300 to the transmitter 13, if the power transmitting device 10 receives the prescribed signal 1000 from the first power receiving device, the power transmitting device 10 ends the transmission of the third electromagnetic wave 2300. This allows the power transmitting device 10 to confirm that the battery shortage in the first power receiving device has been relieved and to return to the normal schedule, making maintenance unnecessary.

In addition, if the power transmitting device 10 continues to be unable to receive the prescribed signal 1000 from the power receiving device 20D despite the third electromagnetic wave 2300 radiated in all directions reaching the power receiving device 20D, the power transmitting device 10 notifies the power receiving device 20D that it has determined to have a low battery. This allows the power transmitting device 10 to make an administrator or the like aware of a power receiving device 20 that has a low battery among multiple power receiving devices 20, thereby contributing to a rapid response to that power receiving device 20.

[Processing Procedure of Power Transmission Device According to Second Embodiment]
Fig. 14 is a flowchart illustrating an example of a processing procedure executed by the power transmission device 10 according to the second embodiment. The processing procedure illustrated in Fig. 14 is realized by the control unit 17 of the power transmission device 10 executing the program 16A. The processing procedure illustrated in Fig. 14 is repeatedly executed by the control unit 17.

In the processing procedure shown in FIG. 14, steps that are substantially the same as those shown in FIG. 11 are given the same reference numerals. In the processing procedure shown in FIG. 14, steps S101 to S104 and steps S108 to S111 are the same as steps S101 to S104 and steps S108 to S111 in FIG. 11, so their explanation will be omitted.

As shown in FIG. 14, if the control unit 17 of the power transmitting device 10 determines that the specified signal 1000 has not been received from all of the power receiving devices 20 (No in step S102), the control unit 17 proceeds to step S104. The control unit 17 detects the first power receiving device that is low on battery power (step S104). When the process of step S104 ends, the control unit 17 proceeds to step S120.

The control unit 17 changes the power supply schedule SC to include omnidirectional radiation (step S120). For example, the control unit 17 changes the schedule for the first power receiving device in the power supply schedule SC to a schedule for omnidirectional radiation. When the process of step S120 ends, the control unit 17 advances the process to step S121.

The control unit 17 controls power transmission to the multiple power supply devices based on the changed power supply schedule SC (step S121). For example, for each power receiving device 20 indicated by the changed power supply schedule SC, the control unit 17 sets a weight corresponding to the power receiving device 20 other than the first power receiving device in the transmission unit 13, and sequentially causes the antenna 11 to radiate electromagnetic waves 2000 including the transmission signal generated by the transmission signal generation unit 12. The control unit 17 then sets a weight corresponding to omnidirectional radiation in the transmission unit 13, and causes the antenna 11 to radiate a third electromagnetic wave 2300 of omnidirectional radiation including the transmission signal generated by the transmission signal generation unit 12. When the control unit 17 finishes the process of step S121, the process proceeds to step S108.

The control unit 17 determines whether or not the specified signal 1000 has been received from the first power receiving device (step S108). If the control unit 17 determines that the specified signal 1000 has been received from the first power receiving device (Yes in step S108), the process proceeds to step S109.

The control unit 17 restores the second electromagnetic wave and the power supply schedule SC that have been changed (step S109). For example, the control unit 17 restores the beam width 2100 of the second electromagnetic wave and the power supply schedule SC that have been changed in step S106 to the power supply schedule SC before the change. When the processing of step S109 ends, the control unit 17 ends the processing procedure shown in FIG. 14.

If the control unit 17 determines that the specified signal 1000 has not been received from the first power receiving device (No in step S108), the process proceeds to step S110. The control unit 17 determines whether or not the determination time has elapsed (step S110). If the control unit 17 determines that the determination time has not elapsed (No in step S110), the process returns to step S108 already described, and the process continues. If the control unit 17 determines that the determination time has elapsed (Yes in step S110), the process proceeds to step S111.

The control unit 17 executes a notification process for the detected power receiving device 20 with a low battery (step S111). By executing the notification process, the control unit 17 notifies the management device 300, etc., of the detected power receiving device 20 with a low battery. When the process of step S111 ends, the control unit 17 ends the processing procedure shown in FIG. 14.

In the above-mentioned first and second embodiments, the system 1 has been described as being an independent power supply device in which the power transmission device 10 is an independent power supply device, but this is not limited thereto. The electronic device may be realized, for example, by a control device that controls a power supply device capable of emitting electromagnetic waves for power supply, a computer built into the power supply device, etc. Also, the system 1 has been described as being a wireless power transmission system, but this is not limited thereto. For example, the system 1 can be applied to a system that performs wireless communication in an electromagnetic wave propagation environment, etc.

The characteristic embodiments have been described in order to fully and clearly disclose the technology related to the attached claims. However, the attached claims should not be limited to the above-mentioned embodiments, but should be configured to embody all modifications and alternative configurations that a person skilled in the art can create within the scope of the basic matters shown in this specification. The contents of this disclosure can be modified and amended in various ways by a person skilled in the art based on this disclosure. Therefore, these modifications and amendments are included in the scope of this disclosure. For example, in each embodiment, each functional part, each means, each step, etc. can be added to other embodiments so as not to be logically inconsistent, or can be replaced with each functional part, each means, each step, etc. of other embodiments. In each embodiment, multiple functional parts, each means, each step, etc. can be combined into one or divided. In addition, each embodiment of the present disclosure described above is not limited to being implemented faithfully to each of the embodiments described, and can be implemented by combining each feature or omitting some features as appropriate.

[Appendix 1]
a transmitter capable of transmitting a first electromagnetic wave that is an electromagnetic wave capable of supplying power to a battery connected to a power receiving device, or a second electromagnetic wave that is capable of supplying power to a wider range than the first electromagnetic wave;
a power transmission control unit that, when detecting a first power receiving device among the power receiving devices in which the power stored in the battery is equal to or less than a predetermined value, transmits the second electromagnetic wave to a second power receiving device that is located near the first power receiving device and in which the energy stored in the battery is not equal to or less than the predetermined value;
A power transmission device having the above structure.
[Appendix 2]
The second electromagnetic wave is an electromagnetic wave capable of supplying power to the battery connected to the first power receiving device and the battery connected to the second power receiving device.
2. The power transmitting device according to claim 1.
[Appendix 3]
A receiving unit capable of receiving a prescribed signal transmitted by the power receiving device;
a detection unit that determines that the power receiving device, which is unable to confirm the transmission of the regulation signal, has a predetermined or lower amount of power stored in the battery;
2. The power transmitting device according to claim 1,
[Appendix 4]
The power transmission control unit transmits, as the second electromagnetic wave, an electromagnetic wave having a beam width wider than that of the first electromagnetic wave.
4. The power transmitting device according to claim 3.
[Appendix 5]
The detection unit detects the second power receiving device based on the specified signal last received from the first power receiving device.
5. The power transmitting device according to claim 4.
[Appendix 6]
the power transmission control unit controls the transmission of the first electromagnetic wave or the second electromagnetic wave to the power receiving device based on a power supply schedule that specifies an order or timing of transmitting the first electromagnetic wave to the power receiving device.
6. The power transmitting device according to claim 5.
[Appendix 7]
The power transmission control unit generates or changes the power supply schedule based on the regulation signal received from the power receiving device.
7. The power transmitting device according to claim 6.
[Appendix 8]
When the power transmission control unit detects the first power receiving device, the power transmission control unit stops transmission of the first electromagnetic wave according to the power supply schedule to the first power receiving device, and causes the transmission unit to transmit the second electromagnetic wave to the second power receiving device.
8. The power transmitting device according to claim 7.
[Appendix 9]
The power transmission control unit causes the transmission unit to transmit the second electromagnetic wave at a transmission timing defined in the power supply schedule of the first power receiving device.
9. The power transmitting device according to claim 8.
[Appendix 10]
the power transmission control unit, after causing the transmission unit to transmit the second electromagnetic waves, ends the transmission of the second electromagnetic waves when the specified signal is received from the first power receiving device.
10. The power transmitting device according to claim 9.
[Appendix 11]
the first power receiving device is located within a range in which power can be supplied to the battery by the second electromagnetic wave transmitted to the second power receiving device;
2. The power transmitting device according to claim 1.
[Appendix 12]
a transmitter capable of transmitting a first electromagnetic wave that is an electromagnetic wave capable of supplying power to a battery connected to a power receiving device, or a third electromagnetic wave that is capable of supplying power to a wider range than the first electromagnetic wave;
a power transmission control unit that, when detecting a first power receiving device among the power receiving devices whose battery stored power is equal to or less than a predetermined value, transmits the third electromagnetic wave that is radiated in all directions including the installation direction of the power receiving device to a second power receiving device that is located near the first power receiving device and whose battery stored energy is not equal to or less than the predetermined value;
A power transmission device having the above structure.
[Appendix 13]
A receiving unit capable of receiving a prescribed signal transmitted from a plurality of the power receiving devices;
a detection unit that detects the power receiving device as the first power receiving device having a low battery when the specified signal is not received from the power receiving device;
Further equipped with
The power transmission control unit, when the detection unit detects the first power receiving device, causes the transmission unit to transmit the third electromagnetic wave of omnidirectional radiation including an installation direction of the first power receiving device.
13. The power transmitting device according to claim 12.
[Appendix 14]
the power transmission control unit controls transmission of the first electromagnetic wave or the third electromagnetic wave to the power receiving devices based on a power supply schedule for the power receiving devices.
14. The power transmitting device according to claim 13.
[Appendix 15]
the power transmission control unit, when detecting a first power receiving device having a low battery among the plurality of power receiving devices, stops the power supply schedule for the first power receiving device, and then causes the transmission unit to transmit the third electromagnetic wave of omnidirectional radiation including an installation direction of the first power receiving device.
15. The power transmitting device according to claim 14.
[Appendix 16]
The power transmission control unit causes the transmitting unit to transmit the third electromagnetic wave during a time period of the power supply schedule of the first power receiving device in which the battery is insufficient.
16. The power transmitting device according to claim 15.
[Appendix 17]
the power transmission control unit, after causing the transmission unit to transmit the third electromagnetic wave, ends the transmission of the third electromagnetic wave when the specified signal is received from the first power receiving device.
16. The power transmitting device according to claim 15.
[Appendix 18]
A power transmitting device having a transmitting unit capable of transmitting a first electromagnetic wave, which is an electromagnetic wave capable of supplying power to a battery connected to a power receiving device, or a second electromagnetic wave, which is capable of supplying power to a wider range than the first electromagnetic wave,
A power transmission method, when a first power receiving device is detected among the power receiving devices, the power stored in the battery of which is below a predetermined level, the power transmitting unit transmits the second electromagnetic waves to a second power receiving device that is located in the vicinity of the first power receiving device and whose energy stored in the battery is not below the predetermined level.
[Appendix 19]
A power transmitting device having a transmitting unit capable of transmitting a first electromagnetic wave, which is an electromagnetic wave capable of supplying power to a battery connected to a power receiving device, or a third electromagnetic wave, which is capable of supplying power to a wider range than the first electromagnetic wave,
A power transmission method in which, when a first power receiving device is detected among the power receiving devices, the power stored in the battery of which is below a predetermined level, the transmitter transmits the third electromagnetic wave, radiated in all directions including the installation direction of the power receiving device, to a second power receiving device that is located in the vicinity of the first power receiving device and whose energy stored in the battery is not below the predetermined level.
[Appendix 20]
A power transmitting device having a transmitting unit capable of transmitting a first electromagnetic wave, which is an electromagnetic wave capable of supplying power to a battery connected to a power receiving device, or a second electromagnetic wave, which is capable of supplying power to a wider range than the first electromagnetic wave,
When a first power receiving device is detected among the power receiving devices, the power stored in the battery of which is below a predetermined level, the program executes a step of causing the transmitter to transmit the second electromagnetic waves to a second power receiving device that is located in the vicinity of the first power receiving device and whose energy stored in the battery is not below the predetermined level.
[Appendix 21]
A power transmitting device having a transmitting unit capable of transmitting a first electromagnetic wave, which is an electromagnetic wave capable of supplying power to a battery connected to a power receiving device, or a third electromagnetic wave, which is capable of supplying power to a wider range than the first electromagnetic wave,
When a first power receiving device is detected among the power receiving devices and the power stored in the battery is below a predetermined level, the program executes a step of causing the transmitter to transmit the third electromagnetic wave, radiated in all directions including the installation direction of the power receiving device, to a second power receiving device that is located in the vicinity of the first power receiving device and has energy stored in the battery that is not below the predetermined level.
[Appendix 22]
A power transmission device;
a plurality of power receiving devices to which power is supplied by electromagnetic waves received from the power transmitting device;
Equipped with
The power transmitting device is
A transmitter capable of transmitting a first electromagnetic wave capable of supplying electric power to a plurality of power receiving devices;
a power transmission control unit that, when detecting a first power receiving device among the plurality of power receiving devices that is low on battery power, changes a second electromagnetic wave for supplying power to a second power receiving device near the first power receiving device so that the first power receiving device and the second power receiving device can be powered, and transmits the second electromagnetic wave to the transmission unit;
A system comprising:
[Appendix 23]
A power transmission device;
a plurality of power receiving devices to which power is supplied by electromagnetic waves received from the power transmitting device;
Equipped with
The power transmitting device is
A transmitter capable of transmitting a first electromagnetic wave capable of supplying electric power to a plurality of power receiving devices;
a power transmission control unit that, when detecting a first power receiving device having a low battery among the plurality of power receiving devices, causes the transmitting unit to transmit a third electromagnetic wave that is radiated in all directions including an installation direction of the first power receiving device;
A system comprising:

REFERENCE SIGNS LIST 1 System 10 Power transmitting device 11 Antenna 12 Transmission signal generating unit 13 Transmitter 14 Receiver 15 Estimator 16 Memory unit 16A Program 16B Weight data 16C Management data 16D Schedule data 17 Controller 17A Detector 17B Power transmission controller 20 Power receiving device 21 Antenna 22 Generator 23 Converter 24 Battery 30 Management device 1000 Specified signal 2000 Electromagnetic wave 2100 Beam width 2200 Installation direction 2300 Third electromagnetic wave SC Power supply schedule

Claims (16)

a transmitter capable of transmitting a first electromagnetic wave that is an electromagnetic wave capable of supplying power to a battery connected to a power receiving device, or a second electromagnetic wave that is capable of supplying power to a wider range than the first electromagnetic wave;
a power transmission control unit that, when detecting a first power receiving device among the power receiving devices in which the power stored in the battery is equal to or less than a predetermined value, transmits the second electromagnetic wave to a second power receiving device that is located near the first power receiving device and in which the energy stored in the battery is not equal to or less than the predetermined value;
A power transmission device having the above structure. The second electromagnetic wave is an electromagnetic wave capable of supplying power to the battery connected to the first power receiving device and the battery connected to the second power receiving device.
The power transmitting device according to claim 1 . A receiving unit capable of receiving a prescribed signal transmitted by the power receiving device;
a detection unit that determines that the power receiving device, which is unable to confirm the transmission of the regulation signal, has a predetermined or lower amount of power stored in the battery;
The power transmitting device according to claim 1 . The power transmission control unit transmits, as the second electromagnetic wave, an electromagnetic wave having a beam width wider than that of the first electromagnetic wave.
The power transmitting device according to claim 3 . The detection unit detects the second power receiving device based on the specified signal last received from the first power receiving device.
The power transmitting device according to claim 4 . The power transmission control unit controls the transmission of the first electromagnetic wave or the second electromagnetic wave to the power receiving device based on a power supply schedule that specifies an order or timing of transmitting the first electromagnetic wave to the power receiving device.
The power transmitting device according to claim 5 . The power transmission control unit generates or changes the power supply schedule based on the regulation signal received from the power receiving device.
The power transmitting device according to claim 6 . When the power transmission control unit detects the first power receiving device, the power transmission control unit stops transmission of the first electromagnetic wave according to the power supply schedule to the first power receiving device, and causes the transmission unit to transmit the second electromagnetic wave to the second power receiving device.
The power transmitting device according to claim 7 . The power transmission control unit causes the transmission unit to transmit the second electromagnetic wave at a transmission timing defined in the power supply schedule of the first power receiving device.
The power transmitting device according to claim 8 . the power transmission control unit, after causing the transmission unit to transmit the second electromagnetic waves, ends the transmission of the second electromagnetic waves when the specified signal is received from the first power receiving device.
The power transmitting device according to claim 9 . the first power receiving device is located within a range in which power can be supplied to the battery by the second electromagnetic wave transmitted to the second power receiving device;
The power transmitting device according to claim 1 . a transmitter capable of transmitting a first electromagnetic wave that is an electromagnetic wave capable of supplying power to a battery connected to a power receiving device, or a third electromagnetic wave that is capable of supplying power to a wider range than the first electromagnetic wave;
a power transmission control unit that, when detecting a first power receiving device among the power receiving devices whose battery stored power is equal to or less than a predetermined value, transmits the third electromagnetic wave that is radiated in all directions including the installation direction of the power receiving device to a second power receiving device that is located near the first power receiving device and whose battery stored energy is not equal to or less than the predetermined value;
A power transmission device having the above structure. A power transmitting device having a transmitting unit capable of transmitting a first electromagnetic wave, which is an electromagnetic wave capable of supplying power to a battery connected to a power receiving device, or a second electromagnetic wave, which is capable of supplying power to a wider range than the first electromagnetic wave,
A power transmission method, when a first power receiving device is detected among the power receiving devices, the power stored in the battery of which is below a predetermined level, the power transmitting unit transmits the second electromagnetic waves to a second power receiving device that is located in the vicinity of the first power receiving device and whose energy stored in the battery is not below the predetermined level. A power transmitting device having a transmitting unit capable of transmitting a first electromagnetic wave, which is an electromagnetic wave capable of supplying power to a battery connected to a power receiving device, or a third electromagnetic wave, which is capable of supplying power to a wider range than the first electromagnetic wave,
A power transmission method in which, when a first power receiving device is detected among the power receiving devices, the power stored in the battery of which is below a predetermined level, the transmitter transmits the third electromagnetic wave, radiated in all directions including the installation direction of the power receiving device, to a second power receiving device that is located in the vicinity of the first power receiving device and whose energy stored in the battery is not below the predetermined level. A power transmitting device having a transmitting unit capable of transmitting a first electromagnetic wave, which is an electromagnetic wave capable of supplying power to a battery connected to a power receiving device, or a second electromagnetic wave, which is capable of supplying power to a wider range than the first electromagnetic wave,
When a first power receiving device is detected among the power receiving devices, the power stored in the battery of which is below a predetermined level, the program executes a step of causing the transmitter to transmit the second electromagnetic waves to a second power receiving device that is located in the vicinity of the first power receiving device and whose energy stored in the battery is not below the predetermined level. A power transmitting device having a transmitting unit capable of transmitting a first electromagnetic wave, which is an electromagnetic wave capable of supplying power to a battery connected to a power receiving device, or a third electromagnetic wave, which is capable of supplying power to a wider range than the first electromagnetic wave,
When a first power receiving device is detected among the power receiving devices and the power stored in the battery is below a predetermined level, the program executes a step of causing the transmitter to transmit the third electromagnetic wave, radiated in all directions including the installation direction of the power receiving device, to a second power receiving device that is located in the vicinity of the first power receiving device and has energy stored in the battery that is not below the predetermined level.

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