JP3176765B2 - Hybrid power supply for electric traveling vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hybrid power supply for supplying electric power to a motor in an electric traveling vehicle driven by the electric motor.

[0002]

2. Description of the Related Art In recent years, an electric traveling vehicle that is easy to operate with no pollution and no noise has attracted attention and has been put to practical use.
The biggest problem of the electric traveling vehicle is that the battery for storing the electric power to be supplied to the electric motor has a large capacity and a large number of batteries must be mounted in order to extend the travelable distance in one battery charge. .

For example, as described in Japanese Patent Application Laid-Open No. 55-157901, there has been proposed a power traveling vehicle equipped with a so-called hybrid power supply device equipped with an engine generator that automatically operates according to the state of charge of a battery. I have.

A large output of, for example, about 5 kW or more is required for an engine generator used as a hybrid power supply of this type. Therefore, a field coil rotor is used as an engine drive generator having such an amount of power generation. The inner rotor type is generally used.

FIG. 1 shows an example. FIG. 1 is a plan view of an engine generator 01. An engine portion of the engine generator 01 includes a crankcase 02 and the crankcase 02.
1 and a flywheel 05 fixed to a shaft end that penetrates the side wall of the crankcase 02 to the left in FIG.

On the right side of the crankcase 02 is a generator
The generator 06 has a cylindrical shape in which a field coil rotor is coaxially connected to the crankshaft 04 and a wound stator is disposed therearound.

[0007]

In such a field winding type engine generator for obtaining a relatively large output, the diameter of the rotor cannot be so large because of considerations such as over-rotation strength of the rotor. As described above, since the smooth rotation of the engine is not secured only by the rotating mass of the rotor, the flywheel 05
I have to prepare.

As described above, since the rotor is long in the axial direction and the flywheel 05 is required, the generator 06 is increased in size as shown in FIG.
However, the overall size of the device increased, and an increase in weight was inevitable.

This does not sufficiently address the conventional problem of an electric traveling vehicle that wants to make the power supply section including the battery as small and light as possible to secure the original living space and load space. become.

In a small engine working machine such as a cultivator, a small part of the output of the engine is taken out from a flywheel generator and used for night lighting or the like.
The output to be taken out is at most about several tens of watts, and it is hardly considered that this constitutes a hybrid power source of the electric traveling vehicle.

In view of such circumstances, the present invention is to provide a hybrid power supply device for an electric traveling vehicle that can secure sufficient required power while being substantially the size and weight of the engine alone.

[0012]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a battery for driving an electric motor serving as a driving source for driving, and an engine generator for supplying charging power to the battery. In the hybrid power supply device for an electric traveling vehicle, the engine-driven generator is mounted on a crankcase side wall of the engine so as to penetrate an output shaft of the engine, and a plurality of salient pole portions radially protrude from an annular yoke portion. A stator formed by winding at least a three-phase coil around the salient pole portion of the annular star core,
An outer rotor type magnet rotor having a plurality of permanent magnets fixed along an inner periphery of a cup-shaped flywheel mounted on the output shaft end of the engine passing through the stator so as to cover the stator. And a rectifying means for rectifying and summing the outputs of the at least three-phase coils and extracting a DC output for supplying to the battery when the motor / generator operates as a generator. And an inverter for supplying electric power from the battery to the at least three-phase coils when the motor / generator operates as an engine starting motor, wherein the motor / generator is operated as a generator. the DC output voltage at no load operation, set to be higher than the range of variation of the terminal voltage of the battery, and bets
The connection with the output side of the motor / generator is disconnected.
The electric traveling is configured so that the operation of the engine is stopped when the power is turned on, and the full power of the electric motor / generator driven by the engine is supplied to the battery without the no-load operation. A hybrid power supply for a vehicle is obtained.

First, an engine generator has a flywheel mounted on an engine output shaft in a cup shape, a permanent magnet fixed to the inner periphery of the flywheel to form an outer rotor type magnet rotor, and a generating coil wound inside the rotor. The structure is provided with a stator of a ring-shaped iron core as described above, so that it is possible to adopt a structure similar to a conventional flywheel unit in which a generator is incorporated, and a conventional generator that greatly protrudes as shown in FIG. The main body has been eliminated, and a significant reduction in size and weight can be achieved.

Further, in addition to the above configuration, since a plurality of permanent magnets are provided along the inner periphery of the outer rotor type rotor, sufficient strength can easily be secured even with a large centrifugal force. The outer rotor type magnet rotor can increase the output by shortening the axial length and increasing the diameter to facilitate multipolarization (at least three phases), and shorten the output winding length at the time of multipolarization. As a result, the power generation efficiency can be improved, the surface area can be increased, and the heat radiation can be improved.

The outputs of the respective output windings are rectified and added to be supplied to the main battery, and the output of the engine is entirely used for driving the generator. Despite the size and weight of the system, it is possible to secure sufficient power required for the entire system.

[0016] DC output voltage during no-load operation of the engine-driven generator, by set higher than the variation range of battery terminal voltage, direct current also varies with the battery charging less engine power Connection between the battery and the output side of the motor / generator
When the power supply is cut off, the engine is stopped, so that it is possible to prevent the adverse effects associated with the generation of high voltage due to the no-load operation of the high-power generator.

The engine is set by the governor so as to be operated at a constant speed near the rotational speed of the optimum fuel efficiency, so that the fuel consumption is small, the economy is low, the exhaust gas is small, and a stable battery is provided. Can be charged.

Further, a cooling fan provided in the outer rotor type magnet rotor, and an air guide path which covers the entire outer rotor type magnet rotor side and guides cooling air sucked by the cooling fan to a cylinder portion of the engine. By providing the fan cover forming the above, a compact engine generator cooling structure that efficiently cools the generator and the engine cylinder can be configured with the same configuration as the conventional engine alone.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention shown in FIGS. 2 to 8 will be described below. FIG. 2 is a plan view of the engine generator 1 constituting the hybrid power supply device of the present invention,
FIG. 3 is a side view thereof.

The engine 2 of the engine generator 1 has a cylinder 4 projecting obliquely upward from a crankcase 3 in the same manner as in the prior art, and a carburetor 5 connected to a left side of the cylinder 4 in FIG. An air cleaner 6 is further disposed on the left side of 5.

The left side of the crankcase 3 has a fan cover 7
The fan cover 7 extends to the left side of the cylinder 4, where an exhaust port (not shown) that opens to the right side of the cylinder 4 is formed.

The generator 20 driven by the engine 2 has a flywheel inside the fan cover 7 as described later.
It is configured to be integrated into 27 parts (see FIG. 4). In this embodiment, a motor generator is used as the generator 20. However, the details will be described later.
Proceed with 20.

The engine 2 has an automatic governor (governor). The base end of the governor arm 12 is fitted to the end of the governor shaft 11 protruding from the crankcase 3. Governor link between tip and throttle lever link 14 provided on carburetor 5
Connected at 13.

The governor link 13 of the governor arm 12
An extension 12a is integrally formed on the opposite side of the mounting portion,
Holes 12 b and 12 c are formed in the extension 12 a at different distances from the governor shaft 11. One of these holes
A throttle spring 15 is provided between the 12b and a fixed point of the crankcase 3.

The holes 12b, 12 of the throttle spring 15
By changing c, the urging force against the swing of the governor arm 12 about the governor shaft 11 can be changed, whereby the engine speed can be changed in two stages.

The displacement of the governor weight (not shown) according to the fluctuation of the rotation speed of the crankshaft causes the governor shaft 11 to rotate, so that the governor arm 12 moves at the balance point against the spring force of the throttle spring 15. Swings and throttle lever link via governor link 13
Rotate 14

Since the throttle lever link 14 is interlocked with the throttle valve, the opening / closing amount of the throttle valve is controlled in accordance with the rotation speed, so that the rotation speed can be maintained substantially constant even when the load varies. .

Next, the structure of the generator 20 will be described with reference to FIGS. The crankshaft 21 is drawn to the left in FIG. 4 from the side wall 3a of the crankcase 3 via a bearing, and radially extends from the annular yoke portion 22a to 27 salient pole portions 22.
An annular star-shaped core 22 having a projecting portion b is fixed to a peripheral boss portion of the crankcase side wall 3a around the crankshaft 21 by a bolt 23.

The 27 salient pole portions 22b of the annular star-shaped iron core 22 include:
The three-phase power generating coils 24 are sequentially and alternately wound to form the stator 25. The multi-polarity of the annular star-shaped core 22 makes it possible to take out a large output by making the poles multi-polarized, and it is also possible to shorten the radial dimensions of the annular yoke portion 22a and the salient pole portion 22b, thereby reducing the weight. be able to.

On the other hand, a forged hub 26 is fitted to the end of the crankshaft 21 that penetrates the center of the annular star-shaped core 22.
A flywheel 27 also serving as a rotor yoke is connected to 26.

The flywheel 27 has a disk portion 27a formed by pressing a high-tensile steel plate into a cup shape and a cylindrical portion.
27b, the disk portion 27a is fixed to the hub 26,
The cylindrical portion 27b is attached so as to cover the outside of the salient pole portion 22b of the annular star core 22.

Eighteen neodymium magnets 28 having a high magnetic force are fixed to the inner peripheral surface of the cylindrical portion 27b of the flywheel 27 in the circumferential direction, and an outer rotor type magnet rotor 29 is provided.
Is composed.

As described above, the outer rotor type magnet rotor 29
By laying the neodymium magnet 28 on the inner peripheral surface of the cylindrical portion 27b, a sufficient mass can be secured and a function as a flywheel can be obtained. The flywheel 27 uses high-tensile steel plates to reduce the weight compared to a conventional flywheel and uses a neodymium magnet 28 to obtain a rotating mass, so that the overall weight of the engine generator 1 is reduced. The weight range can be suppressed to substantially the same as the conventional engine alone.

The disk portion 27a of the flywheel 27
Is provided with a cooling fan 30. Cooling fan 30
A plurality of blades 30b are provided on one side surface of an annular substrate 30a in the circumferential direction, and the substrate 30a is fixed to the outer surface of the disk portion 27a of the flywheel 27.

The fan cover 7 that covers the cooling fan 30
Is formed such that an air guide path 7a extending from the side of the flywheel 27 to the cylinder 4 is formed to guide the cooling air toward the cylinder 4 of the engine 2.

Therefore, when the cooling fan 30 rotates integrally with the flywheel 27, air is sucked from the air inlet 7b of the fan cover 7 to cool the generator 20, and the sucked air is guided to the air guide path 7a. After cooling the cylinder 4, the air is exhausted to the outside.

FIG. 6 shows a configuration diagram of a hybrid power supply system incorporating the above-described engine generator 1. The main battery 40 serving as a power source is configured so that a normal charging operation can be performed from an external power supply via an external power supply connection terminal 42 by a vehicle-mounted charger 41.
The output of 40 is controlled by the inverter 43 and supplied to the traveling motor 44, whereby the driving of the traveling motor is controlled.

On the other hand, the engine generator 1 is built in as a self-charging mechanism. It is configured to be supplied to the battery 40.

An overvoltage detector 50 for detecting when the output voltage of the generator 20 is equal to or higher than a predetermined voltage is provided. When the overvoltage detector 50 detects an overvoltage, the ignition signal of the engine 2 is turned off. It is configured to stop the engine.

Further, as described above, the generator 20 is constituted by a motor generator, and the electric power of the main battery 40 is supplied to the generator 20 via the inverter 51 on the contrary, and the generator 20 is driven as a motor. The starter motor of the engine 2 is configured to function as a starter motor.

Therefore, the start switch 46 of the inverter 51,
47 is provided, one start switch 46 is a switch that is manually turned on and off, and the other start switch 46 is provided.
Reference numeral 47 denotes a switch that is controlled to start the inverter 51 when the voltage of the main battery 40 falls below a predetermined value based on the detection voltage of the voltage detector 48 that detects the voltage of the main battery 40.

FIG. 7 shows a connection configuration example of the generator (motor generator) 20 and the main battery 40. The three transistors 62 constitute a three-phase inverter 51 for supplying the power of the main battery 40 to the generator 20. The output of the generator 20 is rectified by six diodes 61 connected in parallel with the respective transistors 62. A three-phase bridge circuit is configured to be supplied to the main battery 40 in total. Each of the transistors 62 is controlled to be turned on and off by the ECU 60.

The generator 20 is provided with a magnetic pole sensor 63, which detects the rotation timing (magnetic pole position) of the outer rotor and sends a signal to the ECU 60. The inverter control of each transistor 62 is performed.

The output terminal of the rectifier 45 is connected to the + terminal of the main battery 40 via a capacitor 64.

While the generator 20 is generating power, the outputs of the respective power generating coils 24 are full-wave rectified and summed by the rectifier 45 and supplied to the main battery 40. At the time of starting, the generator 20 is connected to the inverter 51 by turning on the switch 46 or 47.
The drive signal corresponding to the magnetic pole (rotor magnetic pole position)
The power supplied from the main battery 40 to the generator (= motor) 20 is controlled by supplying the power via U60.

In this embodiment, in particular, immediately after starting, the on-ratio of the inverter is reduced to control the voltage applied to the generator (= motor), that is, by soft-starting, the starting from the weak main battery 40 is started. The supply current is limited so that it can be started without a large current flowing out.

FIG. 8 shows the voltage-current characteristics of the engine generator 1.
Shown in A solid line a indicates a normal voltage-current characteristic, and a broken line b
Is a characteristic when the rotational speed is temporarily increased.

The generator 20 is constituted by a magnet-type generator, and as shown in FIG. 8, by increasing the voltage drop with respect to the increase in the output current, when charging the battery, the current change with respect to the fluctuation of the battery voltage. The characteristics can be reduced.

That is, as shown in FIG. 8, the output voltage during no-load operation (when the current is 0) is set to be higher than the fluctuation range of the terminal voltage of the battery (between the straight lines l ₁ and l ₂ ). Accordingly, since the slope of the solid line a is large, the variation of the charging current is as small as ΔI ₁ with respect to the variation of the battery voltage. Therefore, the charging can be performed by effectively using the engine output.

The engine speed is normally kept at a low speed (for example, 3600 RPM) by the governor mechanism. When the engine speed increases, the characteristic shifts to a broken line b, during which the charging current fluctuates somewhat (ΔI _{2 in} FIG. 8). Since the charging current changes with a positive characteristic with respect to the rotational speed, the stability of the rotational speed is good, and the load can be set near the maximum output of the engine.

Therefore, the magnet-type generator 20 has the advantage that the charging control device for stabilizing the current and the like can be dispensed with, and the load on the engine speed control system is reduced.

When the generator 20 is operated with no load, a considerably high voltage is generated because the generator 20 is a high-power generator. However, in the present invention, the generator 20 is always connected to the main battery 40 via the rectifier 45. In this state, the output voltage is regulated by the battery voltage, and no large output voltage is generated.

If the output voltage of the generator 20 becomes higher than a certain level due to disconnection of the battery wiring or the like, the overvoltage detector 50 detects this and stops the engine to generate an abnormal high voltage. Preventing.

The high voltage value to be detected by the overvoltage detector 50 is set in accordance with the upper limit voltage of the charging of the main battery 40, so that the engine 2 is automatically stopped when the charging is completed. Can also.

The hybrid power supply device of the present embodiment has the above-described configuration, and the generator 20 main body is accommodated in the flywheel 27 so that the generator is not disposed so as to protrude as in the related art. The size and weight of the engine generator 1 are greatly reduced, and the size and weight of the engine generator 1 itself are reduced to about the same size and weight as a conventional engine alone.

Therefore, it is possible to reduce the size and weight of the power supply including the battery, which is the biggest problem in the electric traveling vehicle.

Although the power supply for the engine ignition device is not described in the description of the present embodiment, a CDI ignition device is formed by utilizing a part of the output of the generator, or a permanent magnet is provided on the outer periphery of the flywheel. Various methods can be adopted, such as forming a self-trigger type ignition device equipped with a battery, and further utilizing the output of a battery.

[0058]

According to the first aspect of the present invention, a generator that receives the full output of the engine is incorporated in a form that can obtain a high output in the flywheel of the conventional engine, and the output obtained from the generator is supplied to the main battery. Since the configuration is such that the power is supplied, the size and weight of the engine generator itself are not so different from those of the conventional engine alone, and it is possible to secure sufficient necessary power for the entire system.

Further, by setting the output voltage during no-load operation to be higher than the battery voltage fluctuation range, the change in charging current is reduced so that the engine output can be effectively used and the battery output can be improved.
The connection between the battery and the output side of the motor / generator is disconnected.
When this happens, the engine is stopped, so that it is possible to take out a large amount of electric power, so that it is possible to prevent adverse effects due to high voltage due to no-load operation, which is likely to occur.

According to the second aspect of the present invention, since the engine is operated at a constant speed by the governor at the rotational speed of the optimum fuel efficiency, it is economical, has a small amount of exhaust gas, and can stably charge the battery.

According to the third aspect of the present invention, the cooling fan is provided on the outer rotor type magnet rotor, and the fan cover is configured to guide the cooling air to the engine cylinder. Therefore, the generator has the same configuration as the conventional engine alone. And a compact structure for efficiently cooling the engine cylinder.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of a conventional engine generator.

FIG. 2 is a schematic plan view of an engine generator portion of the hybrid power supply device according to the present invention.

FIG. 3 is a side view of the same.

FIG. 4 is a partially broken plan view of the engine generator portion.

FIG. 5 is a sectional view taken along line VV in FIG. 4;

FIG. 6 is a system configuration diagram showing an embodiment of a hybrid power supply device according to the present invention.

FIG. 7 is a circuit diagram showing a connection configuration between a generator (motor generator) and a main battery.

FIG. 8 is a diagram showing output voltage-output current characteristics of a generator.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Engine generator, 2 ... Engine, 3 ... Crankcase, 4 ... Cylinder, 5 ... Carburetor, 6 ... Air cleaner, 7 ... Fan cover, 11 ... Governor shaft, 12 ... Governor arm, 13 ... Governor link, 14 ... Throttle Lever link, 15… Throttle spring, 20… Generator,
21 ... crankshaft, 22 ... annular star core, 23 ... bolt, 24 ...
Generator coil, 25 stator, 26 hub, 27 flywheel, 28 neodymium magnet, 29 outer rotor magnet rotor, 30 cooling fan, 40 main battery, 41 onboard charger, 42 … External power supply connection terminal, 43… Inverter, 44
... Running motor, 45 ... Rectifier, 46, 47 ... Start switch,
48… Voltage detector, 50… Overvoltage detector, 51… Inverter,
60 ... ECU, 61 ... Diode, 62 ... Transistor, 63 ...
Magnetic pole sensor, 64 ... condenser.

──────────────────────────────────────────────────の Continuation of the front page (51) Int.Cl. ⁷ identification code FI H02K 21/22 H02K 21/22 B (58) Investigated field (Int.Cl. ⁷ , DB name) B60K 6/02 B60L 7 / 00-13/00 H02J 7/00 H02K 7/18

Claims (3)

(57) [Claims] 1. A hybrid power supply device for an electric traveling vehicle, comprising: a battery for driving an electric motor serving as a traveling drive source; and an engine-driven generator for supplying charging power to the battery. At least a three-phase coil is attached to the salient pole portion of an annular star-shaped core that is attached to a crankcase side wall of the engine so as to penetrate the output shaft of the engine and has a plurality of salient pole portions projecting radially from an annular yoke portion. A plurality of permanent magnets are fixed along the inner periphery of a wound stator and a cup-shaped flywheel mounted on the output shaft end of the engine passing through the stator so as to cover the stator. Motor / generator comprising an outer rotor type magnet rotor comprising: an at least three-phase coil when the motor / generator operates as a generator Rectifying means for rectifying and summing the outputs of the above to obtain a DC output for supplying to the battery; and when the electric motor / generator operates as an engine starting electric motor, the electric power from the battery is supplied to the at least three-phase coil. An inverter is provided to supply a DC output voltage during a no-load operation when the electric motor / generator is operated as a generator is set to be higher than a fluctuation range of a terminal voltage of the battery, and The connection between the battery and the output side of the motor / generator is disconnected.
When the state is reached, the operation of the engine is stopped , and the motor / generator driven by the engine is configured to supply the full output to the battery without the no-load operation. A hybrid power supply for an electric traveling vehicle. 2. The hybrid power supply device for an electric traveling vehicle according to claim 1, wherein the engine is set by a governor so as to be driven at a constant speed near a rotation speed of an optimum fuel efficiency. 3. A cooling fan provided on the outer rotor type magnet rotor, and a wind guide for covering the entire outer rotor type magnet rotor side and guiding cooling air sucked by the cooling fan to a cylinder portion of the engine. The hybrid power supply device for an electric traveling vehicle according to claim 1, further comprising a fan cover that forms a road.