CN105159316A - Three dimensional electric field difference obstacle avoidance method for patrolling charged transmission line by unmanned helicopter - Google Patents

Abstract

The invention discloses a three-dimensional electric field differential obstacle avoidance method for an unmanned helicopter to inspect live transmission lines. The method adopted is to install three electric field sensors on the unmanned helicopter on the inspection line. The electric field strength value is collected to the data acquisition processor, the data acquisition processor is composed of a DSP module, the electric field sensor and the signal acquisition processing unit enter the DSP data processing module, and the DSP data processing module outputs to the UAV flight control system, and the DSP data processor Internally, according to a certain algorithm and the strategy of avoiding wires, the airborne flight control system issues instructions to adjust the flying height and direction of the drone, realizing the obstacle avoidance of the unmanned helicopter on the high-voltage transmission line, which can effectively avoid unmanned helicopters. When inspecting live wires, if the unmanned helicopter collides with the transmission line due to deviation from the predetermined course, the safety of the unmanned helicopter inspection system and the transmission line is guaranteed.

Description

A three-dimensional electric field differential obstacle avoidance method for unmanned helicopter inspection of live transmission lines

technical field

The invention relates to an unmanned helicopter obstacle avoidance method, in particular to a three-dimensional electric field differential obstacle avoidance method for an unmanned helicopter to inspect live transmission lines.

Background technique

With the gradual expansion of the construction scale of high-voltage, ultra-high-voltage and ultra-high-voltage power grids in my country, the total distance of high-voltage transmission lines is also increasing. The inspection of transmission lines is becoming more and more important to the safety of power transmission. Safe and stable operation is very important. With the increase of voltage level, the height of line towers is getting higher and higher, and the inspection work of transmission lines needs to be carried out quickly and efficiently. The current line inspection method is more advanced to use unmanned helicopters for line inspection. When the current unmanned helicopter patrols the line, it often involves unmanned helicopter obstacle avoidance. The existing unmanned helicopter obstacle avoidance, such as the patent "CN201210222437" An electric field differential obstacle avoidance system and method for unmanned aerial vehicle inspection with dotted wires" is to detect and judge the position by comparing the change of the electric field intensity at the position of the unmanned aerial vehicle with the simulation results. During the detection process Among them, the patent "CN201210222437" uses the change rate of the difference between the two electric field strengths of the transmission line section, when the UAV is flying on the transmission line, the UAV is required to fly parallel to the transmission line, in fact, it may not be on a horizontal line , so the results obtained by this detection method have limitations on the flight safety of UAVs.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies of the prior art, and provide a three-dimensional space obstacle avoidance of the unmanned helicopter to the power transmission wire, avoiding the unmanned helicopter when the live wire is inspected, due to GPS navigation error or insufficient flight height A three-dimensional electric field differential obstacle avoidance method for unmanned helicopters to inspect live transmission lines to ensure the safety of unmanned helicopters and transmission lines due to collisions between unmanned helicopters and transmission lines.

A three-dimensional electric field differential obstacle avoidance method for an unmanned helicopter to inspect live transmission lines. An electric field intensity measurement sensor, a DSP data processor, and three identical electric field measurement circuits are installed on the unmanned helicopter. Each electric field measurement circuit includes sequentially Connected electric field measurement sensor, signal processing unit, DSP data processor. The output end of the DSP data processor is connected to the UAV flight control system. The electric field obstacle avoidance device as a whole should be located at the central position directly below the body of the inspection unmanned helicopter and at the oblique upper position, and the two electric field measurement circuits at the bottom are symmetrically installed. The specific steps are:

(1) When operating an unmanned helicopter to inspect live wires, the fuselage should keep a horizontal direction and fly along the transmission line; record the installation distances of the three electric field measurement sensors as a, b, and c, and input them to the DSP data processor ; The electric field measurement sensor processes the numerical signal of the measured electric field strength and sends it to the DSP data processor;

(2) According to the electric field intensity data collected by the electric field measurement sensor, the obstacle avoidance judgment is carried out; the specific process is:

a. Simulation calculation, establish an electric field calculation model for the transmission wire, and use the electric field numerical calculation software Ansys to perform simulation calculations to obtain the numerical distribution of the electric field intensity at a certain distance from the transmission line, where the limits of the electric field intensity change rates k ₁ and k ₃ are respectively k ₁ (220)=43V/m ² , k ₃ (220)=160V/m ² , k ₁ (500)=63V/m ² , k ₃ (500)=371V/m ² ;

b. Obstacle avoidance and altitude adjustment judgment. The judgment algorithm of the DSP data processor is as follows: at a certain time T, the values measured by the three electric field measurement sensors are processed and transformed and recorded as n ₁ , n ₂ , and n ₃ respectively, and input into the DSP data processor to obtain the following judgment instructions:

When , output the "safety" command to the flight control system;

When , output the "safety" command to the flight control system;

When , output the "horizontal obstacle avoidance"command;

When , output the "altitude is too low to avoid obstacles"command;

c. Action commands for obstacle avoidance and height adjustment. The DSP sends an instruction to the flight control system. When the instruction is "safe", continue the current flight mission; command to fly" or "raise altitude to avoid obstacles".

In the obstacle avoidance method of the present invention, the measured electric field strength value is input to the signal acquisition unit by the electric field measurement sensor, and then transmitted to the DSP data processor, and the data is calculated and processed by a certain algorithm in the processor, and the generated obstacle avoidance and height adjustment judgment The command is input into the flight control system, and the safety, height adjustment and obstacle avoidance commands are sent to the steering gear controller to control the flight status of the unmanned helicopter. At the same time, the on-board control computer of the flight control system will interact with the ground station through the data transmission station together with the information of obstacle avoidance judgment.

In summary, compared with the prior art, the present invention has the following advantages:

1) The present invention designs a three-dimensional electric field differential obstacle avoidance method for unmanned helicopters to inspect live wires. Using this system, it is possible to realize obstacle avoidance when unmanned helicopters inspect live wires and ensure the safety of unmanned helicopters in inspection of live wires. .

2) The three-dimensional electric field differential obstacle avoidance system for unmanned helicopter inspection of live wires belongs to passive measurement and avoids some shortcomings of active measurement, such as being able to overcome the low accuracy rate of other equipment detection methods, excessive equipment volume and weight.

3) The above-mentioned three-dimensional electric field measurement and obstacle avoidance method of the unmanned helicopter patrolling the live wire is to measure the power frequency electric field of the transmission line, which can collect relatively strong signals and data, and has good anti-interference performance. Taking 220kV and 500kV voltage level transmission wires as examples, the simulation calculation results for comparison and judgment are provided.

Description of drawings

Figure 1 is the structure and data flow chart of the electric field measurement and obstacle avoidance system for unmanned helicopter inspection live wires.

Fig. 2 Layout diagram of electric field strength measuring sensor.

Fig. 3 is a simulation relationship diagram corresponding to the rate of change of the spatial electric field in the horizontal direction of the 220kV transmission wire.

Figure 4 shows the rate of change of the electric field in the vertical direction where the horizontal distance between the 220kV transmission conductor and the side-phase conductor is 30m.

Figure 5 is a diagram of a 220kV iron tower.

Fig. 6 is a simulation relationship diagram corresponding to the rate of change of the spatial electric field in the horizontal direction of the 500kV transmission wire.

Figure 7 shows the rate of change of electric field in the vertical direction where the horizontal distance between the 500kV transmission conductor and the side-phase conductor is 30m;

Figure 8 is a diagram of a 500kV iron tower.

In Fig. 1, the original parts of each part are respectively: 1. Electric field measurement sensor, 2. Signal acquisition module, 3. DSP data processor, 4. Control computer of flight control system, 5. Gyro stabilization platform, 6. Servo control component, 7 . Communication components, 8. Satellite positioning module, 9. Steering gear controller, 10. Electric field obstacle avoidance device.

Detailed ways

The present invention will be described in more detail below in conjunction with examples.

Example 1:

In Fig. 1, it comprises inspection unmanned helicopter, is provided with electric field obstacle avoidance device 10 on unmanned helicopter, and this device comprises DSP data processor 3, three roads identical electric field measurement loops, each electric field measurement loop includes sequentially connected The electric field measurement sensor 1, the signal acquisition module 2 and the DSP data processor 3, the output end of the DSP data processor 3 is connected with the flight control system 4.

The electric field sensors A and B are installed right below the body of the unmanned helicopter, and the electric field sensor C is installed above the unmanned helicopter, and the two electric field measurement circuits of A and B are installed symmetrically.

The electric field measurement sensors A, B, and C respectively input the measured electric field strength values to the signal acquisition module 2, and the measured electric field strength values are input to the DSP data processor 3 (the same is true for the three electric field measurement circuits), as described in the above step b Algorithm processing, the generated judgment results are input into the flight control system control computer 4, and then the obstacle avoidance and attitude adjustment instructions are sent to the steering gear controller 9 to adjust the flight state of the unmanned helicopter platform. At the same time, the computer of the flight control system will interact with the ground station with status information and obstacle avoidance judgment information.

The steps of height adjustment and obstacle avoidance method of the present invention are:

Step 1: Install the electric field sensor. When the unmanned helicopter is inspecting the live wire, the electric field obstacle avoidance device 16 as a whole includes three parts A, B, and C, wherein the A and B parts are located in the central position directly below the unmanned helicopter body and are left and right symmetrical, and C is located above the side of the unmanned helicopter. Position, three electric field measurement sensors 1, three signal acquisition and processing 2 as shown in Figure 1, adopt the three-dimensional electric field differential obstacle avoidance system of above-mentioned installation method, when the unmanned helicopter inspects live conductors, the fuselage needs to be in line with the transmission conductor direction Basically parallel (this is generally the case when unmanned helicopters inspect live wires, so that the validity of the three electric field strength value differences can be guaranteed). Note that the installation distances of the three electric field measuring sensors A, B, and C are AB=a, BC=b, and AC=c respectively.

Step 2: Input the installation intervals a, b, and c of the three electric field measurement sensors l into the DSP data processor.

Step 3: According to the data collected by the electric field measurement sensor 1 in the electric field obstacle avoidance device 10, judge the obstacle avoidance and height adjustment instructions.

a. Simulation calculation.

The electric field calculation model is established for the transmission line, and the electric field numerical calculation software ANSYS is used for simulation calculation to obtain the numerical distribution of the electric field intensity at a certain distance of the transmission line. Set a limit value of the rate of change of electric field intensity (k1, k3 values in the following formula), and the simulation results show that the limit values of the rate of change of electric field intensity for 220kV and 500kV transmission lines correspond to k1(220)=43V/m2, k3(220)=160V/m2, k1(500)=63V/m2, k3(500)=371V/m2.

b. Obstacle avoidance and altitude adjustment judgment.

The judgment algorithm of the DSP data processor is as follows:

When the unmanned helicopter inspects the live wire, at a certain moment, the values measured by the three electric field measurement sensors (respectively denoted as n1, n2, n3) are input to the DSP data processor, and the following judgment operation is performed:

When , output the "safety" command to the flight control system;

When , output the "safety" command to the flight control system;

When , output the "horizontal obstacle avoidance"command;

When , output the "altitude is too low obstacle avoidance"command;

Among them, k1 and k3 are the limit values of the rate of change of electric field intensity respectively.

c. Action commands for obstacle avoidance and height adjustment. The DSP sends an instruction to the flight control system. When the instruction is "safe", continue the current flight mission; Obstacle Avoidance" command.

After the electric field measurement sensor 1 inputs the measured electric field strength value into the signal acquisition process 2, it is input to the DSP data processor 4 (all the three electric field measurement circuits are like this), and the algorithm is processed according to the above-mentioned step b, and the generated judgment command is input into the flight control The system onboard computer 4 will adjust the flight control servo 6 to change the flight status.

In the above step a, the values of k1 and k3 are different for transmission lines of different voltage levels; for wires with the same voltage level and different line parameters (including wire spacing, wire height from the ground, and wire type), the electric field strength values are slightly different. For k1 , k3 value calculation, as follows:

Result one:

k1(220)=43V/m2, k3(220)=160V/m2, k1(500)=63V/m2, k3(500)=371V/m2.

The 220kV transmission wire is simulated and modeled, and Figure 3 is a simulation relationship diagram corresponding to the spatial electric field change rate in the horizontal direction of the 220kV transmission wire.

Take k1 as the rate of change of electric field intensity at a distance of 18m from the conductor, and take k1 as the value of the rate of change of electric field intensity at a distance of 18m from the horizontal conductor, that is, k1(220)=43V/m2.

Figure 4 shows the rate of change of the electric field in the vertical direction where the horizontal distance between the 220kV transmission conductor and the side-phase conductor is 30m;

Take k3 as the value of the change rate of electric field intensity when it is vertically ±10m away from the horizontal plane of the conductor, k3(220)=160V/m2.

Figures 3 and 4 are simulation data. The three-dimensional electric field intensity change rate obstacle avoidance and height adjustment system can also generate flight adjustment signals according to the preset spatial distance from the wire, which illustrates the practicability of the three-dimensional electric field intensity obstacle avoidance system and simulation data.

Result two:

Simulation modeling is carried out on the 500kV transmission wire, and Fig. 6 is a simulation relationship diagram corresponding to the spatial electric field change rate in the horizontal direction of the 500kV transmission wire.

Take k1 as the value of the rate of change of electric field intensity at a distance of 22m from the horizontal conductor, that is, k1(500)=63V/m2.

Figure 7 shows the rate of change of the electric field in the vertical direction where the horizontal distance between the 220kV transmission conductor and the side-phase conductor is 30m.

Take k3 as the value of the rate of change of the electric field intensity when it is 22m vertical from the horizontal plane of the conductor, that is, k3(500)=371V/m2.

Figures 6 and 7 are simulation data. The three-dimensional electric field intensity change rate obstacle avoidance and height adjustment system can also generate flight adjustment signals according to the preset spatial distance from the wire, which illustrates the practicability of the three-dimensional electric field intensity obstacle avoidance system and simulation data.

Although the specific implementation of the present invention has been described above in conjunction with the accompanying drawings, it does not limit the protection scope of the present invention. Those skilled in the art should understand that on the basis of the technical solution of the present invention, those skilled in the art do not need to pay creative work Various modifications or variations that can be made are still within the protection scope of the present invention.

The parts not described in this embodiment are the same as the prior art.

Claims (1)

1. a three-dimensional electric field differential obstacle avoidance method of unmanned helicopter inspection live transmission line, it is characterized in that: on unmanned helicopter, be provided with electric field strength measurement sensor, DSP data processor, three roads are completely identical electric field measurement loops, Each electric field measurement circuit includes an electric field measurement sensor connected in sequence, a signal processing unit, a DSP data processor, and the output end of the DSP data processor is connected to the UAV flight control system. The central position directly below the helicopter body and the obliquely upper position, the two electric field measurement circuits at the bottom are symmetrically installed left and right, and the specific steps are as follows: (1) When inspecting unmanned helicopters to inspect live wires, the fuselage should maintain a horizontal direction and fly along the transmission line; record the installation distances of the three electric field measurement sensors as a, b, and c, and input them for DSP data processing The electric field measurement sensor processes the numerical signal of the measured electric field strength and sends it to the DSP data processor; (2): According to the electric field strength data collected by the electric field measurement sensor, the judgment of obstacle avoidance and height adjustment instructions is carried out; the specific process is: a. Simulation calculation, establish an electric field calculation model for the transmission wire, use the electric field numerical calculation software ANSYS to perform simulation calculation, and obtain the numerical distribution of the electric field intensity at a certain distance from the transmission line, where the limits of the electric field intensity change rates k ₁ and k ₃ are respectively When the voltage is 220kV, k ₁ =43V/m ² , k ₃ =160V/m ² , when the voltage is 500kV, k ₁ =63V/m ² , k ₃ =371V/m ² ; b. Obstacle avoidance and height adjustment judgment, the judgment algorithm of the DSP data processor is as follows: at a certain time T, the values measured by the three electric field measurement sensors are processed and transformed and recorded as n ₁ , n ₂ , n ₃ respectively, and input to the DSP The data processor draws the following judgment instructions: When , output the "safety" command to the flight control system; When , output the "safety" command to the flight control system; When , output the "horizontal obstacle avoidance"command; When , output the "altitude is too low obstacle avoidance"command; c. Obstacle avoidance and altitude adjustment action commands are issued by the DSP to the flight control system. When the command is "safe", the current flight mission will continue; The unmanned helicopter hovers and issues commands to "fly in the opposite direction" or "raise altitude to avoid obstacles" through judgment.