JP4349113B2 - Electric generator for vehicle - Google Patents

Description

  The present invention relates to a vehicular generator-motor apparatus.

  In recent years, prevention of air pollution caused by vehicle exhaust gas and improvement in vehicle fuel efficiency have been strongly desired. For this reason, so-called idle stop vehicles, which stop the engine when the idling state continues for a certain time when the vehicle is stopped, such as waiting for a signal, are increasing. In this idle stop vehicle, a generator-motor apparatus in which an alternator function and a starter function are integrated is used.

By the way, the alternator generates electric power even during idling, as disclosed in JP-A-5-328799. For this reason, the generator-motor apparatus mounted on the idle stop vehicle generates power even during idling, as in the case of the alternator.
JP-A-5-328799

  By the way, the generator motor is composed of a motor generator (generator motor) and a control device (control means). The motor generator generates AC power by receiving driving power from the engine, and generates driving power by being supplied with AC power from the control device. The control device has an inverter circuit composed of a plurality of switching elements. The inverter circuit converts AC power from the motor generator into DC power, converts DC power from the battery (DC power supply) into AC power, and supplies the AC power to the motor generator. Here, with reference to FIG. 4, the temperature of the inverter circuit of the generator-motor apparatus mounted on the idle stop vehicle will be described. In the figure, t0 indicates engine start start, t1 indicates engine start completion, t2 indicates vehicle stop, t3 indicates engine stop or idle stop, t4 indicates engine restart start, and t5 indicates engine restart completion. .

  First, at the time of engine start (t0 to t1), the generator motor operates as a starter. At this time, the inverter circuit converts the DC power from the battery into AC power and supplies it to the motor generator. Therefore, a large current flows through the inverter circuit, and the temperature of the inverter circuit rises rapidly from the ambient temperature.

  Thereafter, during engine operation (t1 to t2), the generator motor operates as an alternator. The inverter circuit converts AC power from the motor generator into DC power. At this time, the current flowing through the inverter circuit is smaller than when the engine is started, and the temperature of the inverter circuit decreases and stabilizes to a substantially constant value.

  Further, when the vehicle stops due to a signal waiting or the like, the engine is in an idling state. When the engine idling state continues for a certain period of time, the engine stops, that is, idle stops. During the period from the vehicle stop to the idle stop (t2 to t3), the generator motor operates as an alternator and continues power generation. At this time, the temperature of the inverter circuit remains stable at a substantially constant value.

Next, from the idle stop until the engine restart is started (t3 to t4),
The engine is stopped and the generator motor is also stopped. However, the inverter circuit is miniaturized and incorporated in the generator motor as part of the control device. Therefore, the temperature of the inverter circuit is hardly lowered only by natural air cooling.

  After that, at the time of engine restart (t4 to t5), the generator motor operates as a starter. For this reason, the temperature of the inverter circuit rapidly increases as in the engine start (t0 to t1).

  As a result, the maximum temperature of the inverter circuit, T0max, becomes very high due to the heat generated during power generation and the heat generated during engine start. Here, the size of the switching element of the inverter circuit is determined by the maximum temperature and the capacity of the flowing current. Therefore, as described above, in the generator-motor apparatus that continues power generation from the vehicle stop to the idle stop, it is necessary to use a large-capacity switching element, and it is difficult to reduce the size of the inverter circuit.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a vehicular generator-motor apparatus that can be reduced in size while ensuring performance.

  Therefore, as a result of intensive research and trial and error to solve this problem, the present inventor has come up with the idea that the temperature can be reduced by stopping power generation when the vehicle engine is idling, and the present invention has been completed. It came to do.

  That is, the vehicular generator-motor apparatus according to claim 1 has a field winding and an armature winding, and is mounted on the vehicle to generate power by the driving force of the engine of the vehicle and to start the engine of the vehicle. A generator motor that generates a driving force of the motor, and a control that controls a field current that flows through the field winding connected to the generator motor and performs AC / DC bidirectional power conversion between the armature winding and a DC power source. And a vehicle generator-motor apparatus comprising: a cooling means for cooling the control means by the driving force of the engine of the vehicle; and the control means further comprises: a brake of the vehicle; The power generation of the generator motor is stopped when the speed is equal to or lower than a predetermined speed, and the cooling means cools the control means even after the power generation of the generator motor is stopped.

  The vehicular generator-motor apparatus according to claim 2 is the vehicular generator-motor apparatus according to claim 1, wherein the control means is configured such that the brake of the vehicle is turned on and the speed of the vehicle is zero. The power generation of the generator motor is stopped at a certain time.

  The vehicular generator-motor apparatus according to claim 3 has a field winding and an armature winding, and is mounted on the vehicle to generate electric power by the driving force of the engine of the vehicle and to drive the engine of the vehicle. A generator motor for generating a force, and a control means for controlling a field current flowing through the field winding connected to the generator motor and performing AC / DC bidirectional power conversion between the armature winding and a DC power source; And a vehicular generator-motor apparatus provided with a cooling means for cooling the control means by the driving force of the engine of the vehicle. Further, in the control means, the speed of the engine of the vehicle is equal to or lower than a predetermined speed. Occasionally, the generator motor stops generating power, and the cooling means cools the control means even after the generator motor stops generating power.

  According to a fourth aspect of the present invention, there is provided the vehicular generator-motor apparatus according to the first to third aspects, wherein the control means cuts off a field current flowing in the field winding of the generator-motor. By doing so, the power generation is stopped.

  According to a fifth aspect of the present invention, there is provided the vehicular generator-motor apparatus according to the first to fourth aspects, wherein the cooling means further includes a predetermined time after the generator motor stops generating power. The control means is cooled.

  The vehicular generator-motor apparatus according to claim 6 is the vehicular generator-motor apparatus according to claim 1, wherein the cooling means further comprises a temperature of the control means after the power generation of the generator-motor is stopped. The control means is cooled until the temperature drops to a predetermined temperature.

  According to the vehicular generator-motor apparatus of the first aspect, when the vehicle brake is turned on and the vehicle speed is equal to or lower than the predetermined speed, the control means stops the power generation of the generator motor. Further, the control means is cooled by the cooling means even after the power generation is stopped. Therefore, the control means does not need to perform AC / DC power conversion from the generator motor to the DC power source, and the temperature of the control means can be suppressed. Furthermore, the temperature of the control means can be reduced by the cooling means. By the way, the control means stops the power generation of the generator motor when the brake is turned on and the vehicle is in a relatively low speed state. However, the AC power generated by the generator at this time is relatively small, and even if power generation is stopped, there is almost no problem. As a result, the control means can be made small while ensuring the performance, and the vehicular generator-motor apparatus can be miniaturized.

  According to the vehicular generator-motor apparatus of the second aspect, when the vehicle brake is turned on and the vehicle speed is zero, the control means stops the power generation of the generator motor. Therefore, the control means does not need to perform AC / DC power conversion from the generator motor to the DC power source, and the temperature of the control means can be suppressed. By the way, the control means stops the power generation of the generator motor when the vehicle is in a stopped state, that is, when the engine is in an idling state. However, the AC power generated by the generator at this time is very small, and there is no problem even if power generation is stopped. As a result, the control means can be made small while ensuring sufficient performance, and the vehicular generator-motor apparatus can be downsized.

  According to the vehicular generator-motor apparatus of the third aspect, when the engine speed of the vehicle is equal to or lower than the predetermined speed, the control means stops the power generation of the generator motor. Further, the control means is cooled by the cooling means even after the power generation is stopped. Therefore, the control means does not need to perform AC / DC power conversion from the generator motor to the DC power source, and the temperature of the control means can be suppressed. Furthermore, the temperature of the control means can be reduced by the cooling means. By the way, the control means stops the power generation of the generator motor when the rotational speed of the engine of the vehicle is equal to or lower than a predetermined rotational speed. However, the AC power generated by the generator motor at this time is relatively small, and there is almost no problem even if power generation is stopped. As a result, the control means can be made small while ensuring the performance, and the vehicular generator-motor apparatus can be miniaturized.

  According to the vehicular generator-motor apparatus of the fourth aspect, the power generation of the generator motor is stopped by interrupting the field current flowing through the field winding by the control means. Therefore, power generation can be stopped reliably and the temperature of the control means can be suppressed. As a result, the control means is reduced, and the vehicular generator-motor apparatus can be further downsized.

  According to the vehicular generator-motor apparatus of the fifth aspect, the control means is cooled by the cooling means until a predetermined time elapses after the power generation of the generator motor is stopped. Therefore, the temperature of the control means can be efficiently reduced. As a result, the control means is reduced, and the vehicular generator-motor apparatus can be further reduced in size.

  According to the vehicular generator-motor apparatus of the sixth aspect, the cooling means cools the control means until the temperature of the control means decreases to a predetermined temperature after the power generation of the generator motor is stopped. Therefore, the temperature of the control means can be reliably reduced to a predetermined temperature. As a result, the control means is reduced, and the vehicular generator-motor apparatus can be further reduced in size.

  The present embodiment shows an example of an idle stop vehicle control device integrated motor generator in which an alternator is provided with an AC motor function and a control device for driving the AC motor is integrated.

  FIG. 1 is a partial cross-sectional view in the axial direction of a motor generator integrated with a control device in this embodiment, FIG. 2 is a circuit diagram of the control device, and FIG. 3 shows the temperature of an inverter circuit of the control device. Then, with reference to these drawings, a specific description will be given in the order of structure, operation, and effect.

  First, a specific structure will be described with reference to FIG. As shown in FIG. 1, a control device integrated motor generator 1 (vehicle generator / motor unit) includes a motor generator 2 (generator / motor unit) incorporating a fan 25 (cooling unit), a control unit 3 (control unit), and the like. It has.

  The motor generator 2 includes a front housing 20, a rear housing 21, a rotating shaft 22, a stator 23, a rotor 24, a fan 25, a pulley 26, and a brush 27.

  The front housing 20 is made of aluminum and includes an end wall 20a and a peripheral wall 20b extending in the axial direction from the peripheral edge of the end wall 20a. A cooling air suction hole 20 c is formed in the end wall 20 a of the front housing 20. Further, a cooling air blowing hole 20 d is formed in the peripheral wall 20 b of the front housing 20.

  The rear housing 21 is made of aluminum like the front housing 20, and is composed of an end wall 21a and a peripheral wall 21b extending in the axial direction from the peripheral edge of the end wall 21a. The end wall 21a of the rear housing 21 is formed with a suction hole 21c for cooling air. Further, a cooling air blowing hole 21 d is formed in the peripheral wall 21 b of the rear housing 21.

  The rotating shaft 22 is a cylindrical body made of, for example, iron. The rotary shaft 22 is connected to the front housing 20 and the rear housing 21 via a bearing 22 a disposed on the end wall 20 a of the front housing 20 and a bearing 22 b disposed on the end wall 21 a of the rear housing 21. It is rotatably supported. Two slip rings 22 c are arranged in parallel in the axial direction on the outer peripheral surface of one end of the rotating shaft 22. A pulley 26 described later is fitted and fixed to the outer peripheral surface of the other end of the rotating shaft 22.

  The stator 23 includes a stator core 23a and a stator coil 23b. The stator core 23a is an annular body made of a magnetic material. The stator coil 23b is a winding wound around the stator core 23a. The outer peripheral surface of one shaft end of the stator 23 is the inner peripheral surface of the end of the peripheral wall 20b of the front housing 20, and the outer peripheral surface of the other shaft end is the end of the peripheral wall 21b of the rear housing 21. Each is fixed to the inner peripheral surface.

  The rotor 24 includes a rotor core 24a and a field coil 24b. The rotor core 24a is made of a magnetic material. The field coil 24b is a winding wound around the rotor core 24a. Both ends of the field coil 24b are connected to two slip rings 22c arranged in parallel at the shaft end of the rotating shaft 22, respectively. The rotor 24 is fixed to the rotary shaft 22 and is disposed on the inner peripheral side of the stator 23 so that the outer peripheral surface of the rotor 24 faces the inner peripheral surface of the stator 23 with a certain distance.

  The fan 25 is fixed to both shaft end faces of the rotor 24. The fan 25 rotates together with the rotor 24 as the rotating shaft 22 rotates to generate an air flow.

  The pulley 26 is fixed to the shaft end portion of the rotating shaft 22 with a screw. The pulley 26 exchanges driving force between the engine and the motor generator 2.

  The brush 27 is a prismatic body made of graphite. The brush 27 is housed in a brush holder 27a and supported so as to be capable of reciprocating in the radial direction. Further, the shaft end surface of the brush 27 is in contact with the outer peripheral surfaces of the two slip rings 22 c disposed at the shaft end portion of the rotating shaft 22. One brush 27 is grounded via the rear housing 21. The other brush 27 is connected to the control device 3 described later.

  As shown in FIG. 2, the control device 3 includes an inverter circuit 30, a field circuit 31, a control circuit 32, a connector 33, a power supply terminal 34, a radiator plate 35, an inverter case 36, and a cover 37. It is composed of

  The inverter circuit 30 is configured by connecting six field effect transistors 30a to 30f having a parasitic diode between a drain and a source in a three-phase bridge connection. The drains of the three field effect transistors 30 a to 30 c on the upper side of the inverter circuit 30 are connected to a power supply terminal 34 described later, and the sources of the three field effect transistors 30 d to 30 f on the lower side are grounded via the rear housing 21. Has been. Further, the three-phase output terminals TU, TV, and TW of the inverter circuit 30 are connected to a stator coil 23b of the motor generator 2 and a control circuit 32 described later.

  The field circuit 31 includes a field effect transistor 31a and a flywheel diode 31b. The drain of the field effect transistor 31 a of the field circuit 31 is connected to the power supply terminal 34, and the source is connected to one end of the field coil 24 b through one brush 27 of the motor generator 2. The cathode of the flywheel diode 31b of the field circuit 31 is connected to one end of the field coil 24b via one brush 27 of the motor generator 2 in the same manner as the source of the field effect transistor 31a. The anode of the flywheel diode 31 b is grounded via the rear housing 21. By the way, the other end of the field coil 24 b is grounded from the other brush 27 via the rear housing 21. Therefore, the flywheel diode 31b is connected in parallel to the field coil 24b.

  The control circuit 32 is connected to the gates of the six field effect transistors 30 a to 30 f constituting the inverter circuit 30 and the gate of the field effect transistor 31 a constituting the field circuit 31. The control circuit 32 is connected to a connector 33 described later and is grounded via the rear housing 21.

  The connector 33 is an electronic member that supplies a control signal from an ignition switch or ECU (not shown) and power for driving to the control circuit 32.

  The power supply terminal 34 is an electronic member that exchanges power between the control device 3 and the battery 4 or each load 5.

  Returning to FIG. As shown in FIG. 1, the heat radiating plate 35 is an annular body made of a material having good thermal conductivity such as aluminum. Six field effect transistors 30a to 30f constituting the inverter circuit 30 are fixed to one end face of the heat radiating plate 35 with screws through insulating films, respectively. A substrate on which the field circuit 31 and the control circuit 32 are mounted is further fixed to one end face of the heat radiating plate 35. A plurality of fins are disposed on the other end face of the heat radiating plate 35 in order to improve the heat radiating effect.

  The inverter case 36 is made of resin, and includes an inner peripheral wall, an outer peripheral wall, and an end wall that connects these shaft end portions. A bus bar is integrally formed on the outer peripheral wall and the end wall of the inverter case 36. A connector 33 and a power supply terminal 34 are fixed to the outer peripheral surface of the outer peripheral wall of the inverter case 36. In a space surrounded by the outer peripheral wall and the inner peripheral wall of the inverter case 36, a heat radiating plate 35 to which the inverter circuit 30, the field circuit 31 and the control circuit 32 are fixed is accommodated. The inverter circuit 30, the field circuit 31, and the control circuit 32 are connected to the stator coil 23 b, the brush 27, the connector 33, and the power supply terminal 34 through a bus bar integrally formed with the inverter case 36. A space surrounded by the inner peripheral wall and the outer peripheral wall of the inverter case 36 is filled with resin. The inverter case 36 is fixed to the end wall 21 a of the rear housing 21.

  The cover 37 is made of resin and includes a bottom wall and a peripheral wall extending in the axial direction from the peripheral edge of the bottom wall. A cooling air suction hole is formed in the bottom wall of the cover 37. The cover 37 is fixed to the end wall 21 a of the rear housing 21 so as to cover the inverter case 36 and the heat radiating plate 35.

  Next, a specific operation will be described with reference to FIG. In FIG. 3, t0 indicates engine start, t1 indicates engine start completion, t2 indicates vehicle stop, t3 indicates engine stop or idle stop, t4 indicates engine restart start, and t5 indicates engine restart completion. .

  First, at the time of engine start (t0 to t1), the generator motor operates as a starter. At this time, the inverter circuit 30 converts the DC power from the battery 4 into AC power and supplies it to the motor generator 2. Therefore, a large current flows through the inverter circuit 30, and the temperature of the inverter circuit 30 increases rapidly from the ambient temperature.

  Thereafter, during engine operation (t1 to t2), the generator motor operates as an alternator. Inverter circuit 30 converts AC power from motor generator 2 into DC power. At this time, the current flowing through the inverter circuit 30 is smaller than when the engine is started, and the temperature of the inverter circuit 30 decreases and stabilizes to a substantially constant value.

  Further, when the vehicle stops due to a signal waiting or the like, the engine is in an idling state. At this time, the brake of the vehicle is turned on and the vehicle speed is zero. This information is input from the ECU for engine control to the control circuit 32 via the connector 33, for example. The control circuit 32 turns off the field effect transistor 31a of the field circuit 31 based on this signal. When field effect transistor 31a of field circuit 31 is turned off, the field current flowing in field coil 24b of motor generator 2 is interrupted, and motor generator 2 stops power generation. By the way, the pulley 26 of the motor generator 2 is coupled to the crankshaft of the engine via a belt. Therefore, the driving force of the engine in the idling state is transmitted to the motor generator 2 via the pulley 26, and the rotor 24 of the motor generator 2 rotates. Thereby, the fan 25 fixed to both end surfaces of the rotor 24 generates a cooling air flow. This cooling air flow flows from the suction hole 20c of the front housing 20 to the blowing hole 20d. Further, the air flows from the air intake hole of the cover 37 through the fins of the heat radiating plate 35, and flows from the inner peripheral side of the inner peripheral wall of the inverter case 36 to the blowout hole 21 d through the intake hole 21 c of the rear housing 21. Then, the inverter circuit 30, the field circuit 31, the control circuit 32, the brush 27, the field coil 24b, and the stator coil 23b are cooled. Here, when the engine idling state continues for a certain period of time, the engine control ECU stops the engine, that is, idle stops. Therefore, this cooling is continuously performed for a certain time (t2 to t3) from the stop of the vehicle to the stop of idling. As a result, the temperature of the inverter circuit 30 is sufficiently lowered.

  Next, from the idle stop until the engine restart is started (t3 to t4), the engine is stopped and the motor generator 2 is also stopped. However, since the inverter circuit 30 is reduced in size and integrated into the motor generator 2, the temperature of the inverter circuit 30 hardly decreases only by natural air cooling.

  After that, at the time of engine restart (t4 to t5), the generator motor operates as a starter. For this reason, the temperature of the inverter circuit 30 rapidly increases as in the engine start (t0 to t1). However, since the temperature of the inverter circuit 30 is sufficiently lowered by stopping the power generation and forced air cooling for a certain time (t2 to t3) from the vehicle stop to the idle stop, the maximum temperature T1max of the inverter circuit 30 is suppressed. be able to.

  Finally, specific effects will be described. First, the controller-integrated motor generator 1 stops the power generation of the motor generator 2 by the control circuit 32 when the vehicle brake is turned on and the vehicle speed is zero. Further, the inverter circuit 30 is cooled by the fan 25 even after power generation is stopped. Therefore, the inverter circuit 30 does not need to perform AC / DC power conversion from the motor generator 2 to the battery 4, and the temperature of the inverter circuit 30 can be suppressed. Further, the temperature of the inverter circuit 30 can be reduced by the fan 25. By the way, the control circuit 32 stops the power generation of the motor generator 2 when the vehicle is stopped, that is, when the engine is idling. However, the AC power generated by the motor generator 2 at this time is very small, and there is no problem even if the power generation is stopped. As a result, the inverter circuit 30 can be made small while ensuring sufficient performance, and the controller-integrated motor generator 1 can be downsized.

  Further, the controller-integrated motor generator 1 stops power generation by interrupting the field current flowing in the field winding of the motor generator 2 by the field circuit 31. Therefore, power generation can be stopped reliably and the temperature of the inverter circuit 30 can be suppressed. As a result, the inverter circuit 30 is reduced, and the controller-integrated motor generator 1 can be further downsized.

  Further, the controller-integrated motor generator 1 cools the inverter circuit 30 with the fan 25 until a predetermined time has elapsed after the power generation of the motor generator 2 is stopped. Therefore, the temperature of the inverter circuit 30 can be efficiently reduced. As a result, the inverter circuit 30 is reduced, and the controller-integrated motor generator 1 can be further reduced in size.

  In the above-described embodiment, the power generation of the motor generator 2 is stopped when the vehicle brake is turned on and the vehicle speed is zero. However, the present invention is not limited to this. Any condition that does not cause a problem even when power generation is stopped may be used. For example, power generation may be stopped when the vehicle brake is turned on and the vehicle speed is equal to or lower than a predetermined speed. Further, the power generation may be stopped by the generator motor when the rotational speed of the vehicle engine is equal to or lower than a predetermined rotational speed. Even under these conditions, the same effect as in the present embodiment can be obtained.

  In the above-described embodiment, the inverter 25 is cooled by the fan 25 until a certain time has elapsed after the motor generator 2 stops generating power, but the present invention is not limited to this. You may cool until the temperature of the inverter circuit 30 falls to predetermined | prescribed temperature. In this case, the temperature can be more reliably reduced.

  Furthermore, a vehicular generator / motor system according to the present invention can be combined with an engine and an ECU to form a vehicular generator / motor system.

FIG. 2 is a partial cross-sectional view in the axial direction of the motor generator integrated with a controller in the present embodiment. The circuit diagram of the control apparatus in this embodiment is shown. The temperature of the inverter circuit of the control apparatus in this embodiment is shown. The temperature of the inverter circuit of the control apparatus in the conventional generator motor apparatus is shown.

Explanation of symbols

1... Controller-integrated motor generator (vehicle generator motor)
2 ... Motor generator (generator motor)
23 ... Stator 23b ... Stator coil 24 ... Rotor 24b ... Field coil 25 ... Fan (cooling means)
26 ... Pulley 27 ... Brush 3 ... Control device (control means)
30 ... Inverter circuits 30a-30f ... Field effect transistor 31 ... Field circuit 31a ... Field effect transistor 32 ... Control circuit

Claims (6)

A generator motor having a field winding and an armature winding, which is mounted on a vehicle and generates electric power by the driving force of the engine of the vehicle and generates a driving force for starting the engine of the vehicle, and is connected to the generator motor Control means for controlling the field current flowing in the field winding and performing AC / DC bidirectional power conversion between the armature winding and a DC power source, and the control means by the driving force of the engine of the vehicle. In the vehicular generator-motor apparatus provided with cooling means for cooling,
Further, the control means stops the power generation of the generator motor when the brake of the vehicle is turned on and the speed of the vehicle is equal to or lower than a predetermined speed,
The vehicular generator-motor apparatus, wherein the cooling means cools the control means even after the generator motor stops generating power.   2. The vehicular generator-motor apparatus according to claim 1, wherein the controller stops power generation of the generator motor when the brake of the vehicle is turned on and the speed of the vehicle is zero. A generator motor having a field winding and an armature winding, which is mounted on a vehicle and generates electric power by the driving force of the engine of the vehicle and generates a driving force for starting the engine of the vehicle, and is connected to the generator motor Control means for controlling the field current flowing in the field winding and performing AC / DC bidirectional power conversion between the armature winding and a DC power source, and the control means by the driving force of the engine of the vehicle. In the vehicular generator-motor apparatus provided with cooling means for cooling,
Furthermore, the control means stops the power generation of the generator motor when the rotational speed of the engine of the vehicle is equal to or lower than a predetermined rotational speed,
The vehicular generator-motor apparatus, wherein the cooling means cools the control means even after the generator motor stops generating power.   4. The vehicular generator-motor apparatus according to claim 1, wherein the control means stops power generation by interrupting a field current flowing through the field winding of the generator motor.   5. The vehicular generator-motor apparatus according to claim 1, wherein the cooling means cools the control means until a predetermined time elapses after power generation by the generator motor is stopped.   5. The vehicular generator-motor according to claim 1, wherein the cooling means cools the control means until the temperature of the control means decreases to a predetermined temperature after power generation of the generator motor is stopped. apparatus.

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