JP2009219191A - Regeneration power controller and regeneration power control method of vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a regeneration power controller of a vehicle that improves operation stability of the vehicle. <P>SOLUTION: The regeneration power controller of the vehicle includes an inverter 6 converting power that a power generator 4 generates into AC power, a motor 8 driving a subordinate driving wheel by AC power that the inverter 6 converts, a power consumption part 64 which is electrically connected in parallel with the inverter 6 between the power generator 4 and the inverter 6 and converts regeneration power that the motor 8 generates into Joule heat so as to consume it, and a switching part 66 connecting a DC-side of the inverter 6 with the power consumption part 64 in a conduction state. When regeneration power is not less than inner loss consisting of loss of the inverter 6 and the motor 8, the switching part 66 is switched to the conduction state, and the DC side of the inverter 6 is connected to the power consumption part 64. A power generation command value to the power generator 4 is controlled so that power that the power generator 4 generates becomes necessary power which the power generator 4 is to generate when driving the subordinate wheels. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  In the present invention, a generator is driven by a main drive source such as an engine which is a drive source of main drive wheels, and a motor which is a drive source of driven wheels is driven by an electric power generated by the generator via an inverter. The present invention relates to a regenerative power control device for a vehicle included in the vehicle.

  Conventionally, in a vehicle that is driven by electric power generated by a generator and includes a motor that is a driving source of a driven wheel, the motor functions as a generator in a traveling state such as rollback or rollforward, and regenerative power is appear. Note that rollback includes retreat on an uphill slope, and rollforward includes regenerative braking and forward movement due to inertia on a downhill slope.

The regenerative power generated in this way returns from the motor to the supply side of the generator, etc., and becomes a factor that suppresses the power generated by the generator. Therefore, the braking force and the torque output by the motor are reduced. May be a factor.
In order to solve such a problem, for example, as described in Patent Document 1, a braking force due to regeneration of the motor is consumed by consuming regenerative power due to internal loss composed of inverter and motor losses. There is an invention that suppresses a decrease in torque output from the motor.

In the invention described in Patent Document 1, in order to consume regenerative power in a state where the battery is fully charged and the regenerative power cannot be stored in the battery, the current is reduced by reducing the voltage applied to the motor. To increase. Thereby, the internal loss comprised from the copper loss of a motor and the loss by the resistance in an inverter is increased, and the regenerative electric power which the motor generated is converted into Joule heat and consumed.
JP-A-5-252606

However, in the method of consuming regenerative power by internal loss including the invention described in Patent Document 1, it is necessary to suppress the power generation amount of the generator within a range that can be consumed by internal loss.
Therefore, even if the vehicle is in a four-wheel drive state when it is shifted from rollback or roll forward to power running and it is desired to increase the torque output by the motor, the amount of power generated by the generator is limited by the internal loss. It will take.

For this reason, even if the power generation amount of the generator is less than the required power to be generated when driving the driven wheels, and a large acceleration force such as climbing on a slope or starting a slope is required, the driven wheels There is a possibility that the problem that it is difficult to set the torque to a desired magnitude is caused.
The present invention has been made paying attention to the above problems, and a regenerative power control device for a vehicle capable of setting the torque of a driven wheel to a desired magnitude when shifting from a regenerative state to powering. It is an issue to provide.

In order to solve the above-described problems, the present invention provides an inverter that converts electric power generated by a generator that generates electric power using a driving force from a main driving source that drives main driving wheels into AC power. Is provided in a vehicle that is supplied to a motor that drives the driven wheel via
A regenerative power control device for a vehicle that consumes the regenerative power generated by the motor on the motor side of the generator,
When the regenerative power is generated, a power consumption unit that consumes the regenerative power that is energized and provided in a power consumption circuit that is electrically connected in parallel with the inverter between the generator and the inverter, and the DC side of the inverter. In accordance with at least one of the DC voltage and the DC current on the DC side of the inverter, the connection or connection is cut off,
When the regenerative power is generated and the inverter is connected to the DC side and the power consuming unit, the generator generates power when the driven wheel is driven. The present invention provides a regenerative power control device for a vehicle, characterized in that control is performed so that the required power to be generated is obtained.

  According to the present invention, the power consuming unit that consumes the energized regenerative power and the DC side of the inverter are connected according to at least one of the DC voltage and the DC current on the DC side of the inverter when the regenerative power is generated. Disconnect the connection. In addition to this, when regenerative power is generated and the power consumption unit is connected to the DC side of the inverter, the power generation command value for the generator is set to the power generated by the generator, and the generator generates power when driving the driven wheels. Control to achieve the required power.

For this reason, the regenerative power generated by the motor as a generator can be consumed on the motor side of the generator by the power consumption unit, and the power generated by the generator can be driven by the driven wheels. Sometimes it is possible to make the required power to be generated by the generator.
As a result, when shifting from the regenerative state to power running, the torque of the motor can be set to the torque required when driving the driven wheels, so that the torque of the driven wheels is set to a desired magnitude. Therefore, it becomes possible to improve the steering stability of the vehicle.

Embodiments of the present invention will be described below with reference to the drawings.
(Embodiment)
(Constitution)
FIG. 1 is a schematic configuration diagram of a vehicle including a regenerative power control apparatus according to the present embodiment.
As shown in FIG. 1, a vehicle including the regenerative power control device of the present embodiment includes an engine 1, a main drive wheel 2, a generator 4, an inverter 6, a motor 8, and a slave drive wheel 10. It is a vehicle which has.
The engine 1 is an internal combustion engine and constitutes a main drive source that drives the main drive wheels 2. In the present embodiment, the main drive wheel 2 is constituted by left and right front wheels 2L and 2R arranged on the left and right, respectively, in front of the vehicle front-rear direction.
For example, a main throttle valve and a sub-throttle valve are interposed in an intake pipe line (not shown) of the engine 1.

  The main throttle valve is connected to an accelerator pedal, which is an accelerator opening degree indicating device, and is configured to adjust and control the opening degree by opening and closing according to the depression amount of the accelerator pedal. The accelerator pedal is provided with an accelerator sensor that detects the accelerator opening. The accelerator sensor transmits an information signal including the detected accelerator opening to the engine controller 12 described later.

  The sub-throttle valve is provided with a step motor as an actuator, and the sub-throttle opening is adjusted and controlled by a rotation angle corresponding to the number of steps of the step motor. The sub-throttle valve is provided with a throttle sensor (not shown), and the number of steps of the step motor is feedback-controlled based on the sub-throttle opening detection value detected by the throttle sensor. .

  Here, by adjusting the sub throttle opening of the sub throttle valve to be equal to or less than the main throttle opening of the main throttle valve, the output torque Te of the engine 1 is reduced independently of the operation of the accelerator pedal by the driver. It is the structure which can be made to do. That is, the control for adjusting the opening of the sub-throttle valve is the driving force control that suppresses the acceleration slip of the main drive wheel 2 by the engine 1.

  The engine controller 12 is connected to the accelerator sensor and the 4WD controller 14, and has a function of adjusting the main throttle opening by electrically adjusting and controlling the main throttle valve and controlling the driving state of the engine 1. . Electrical adjustment control of the main throttle valve is performed based on, for example, the accelerator opening detected by the accelerator sensor and the signal output by the 4WD controller 14.

Front wheel speed sensors 16FL and 16FR are provided on the left and right front wheels 2L and 2R, respectively.
Each front wheel speed sensor 16FL, 16FR detects the rotational speed and rotational speed of the corresponding left and right front wheels 2L, 2R, and outputs an information signal including the detected rotational speed and rotational speed to the 4WD controller 14.
A transmission 18 including a transmission or the like is interposed between the engine 1 and the left and right front wheels 2L and 2R. Thus, when the engine 1 is driven, the rotational torque Te of the engine 1 is transmitted to the left and right front wheels 2L, 2R via the transmission 18.

  The generator 4 is driven using the driving force from the engine 1 as a power source to generate DC power. Specifically, the rotating shaft of the generator 4 is connected to the rotating shaft of the engine 1 via an endless belt 20. As a result, a part of the rotational torque Te of the engine 1 is transmitted to the generator 4 via the endless belt 20, and the rotational speed Nh obtained by multiplying the rotational shaft Ne of the generator 4 by the rotational speed Ne of the engine 1 and the pulley ratio. To generate DC power.

  Further, the generator 4 becomes a load on the engine 1 in accordance with the generator field current Ifg adjusted by the 4WD controller 14, and performs power generation according to the load torque. The magnitude of DC power (generated power) generated by the generator 4 is determined by the magnitude of the rotational speed Ng of the generator 4 and the generator field current Ifg. The rotational speed Ng of the generator 4 can be calculated from the rotational speed Ne of the engine 1 based on the pulley ratio.

An inverter 6 is connected to the generator 4 via an electric wire 22 and a junction box 24. The DC power generated by the generator 4 can be supplied to the inverter 6 via the junction box 24.
The junction box 24 is provided with a relay for connecting or disconnecting the generator 4 and the inverter 6 therein. Then, DC power generated by the generator 4 is supplied to the inverter 6 with this relay connected. The inverter 6 converts the DC power supplied from the generator 4 into AC power such as, for example, three-phase AC and supplies it to the motor 8.

The motor 8 is, for example, a field winding type synchronous motor, and is wound with a rotor (not shown) having a field coil and a three-phase winding (armature coil) for generating a rotating magnetic field. And a stator (not shown). The motor 8 may be a permanent magnet type synchronous motor or an induction motor having a permanent magnet in the rotor other than the field winding type synchronous motor.
The motor 8 rotates by the interaction between a magnetic field generated by passing a current through a field coil of the rotor and a magnetic field generated from an armature coil wound around the stator. Thus, the motor 8 constitutes a slave drive source that drives the slave drive wheels 10. In the present embodiment, the driven wheel 10 is composed of left and right rear wheels 10L and 10R that are arranged on the left and right sides respectively in the rearward direction of the vehicle.

  In addition, when the rotor is rotated by an external force, the motor 8 generates an electromotive force at both ends of the armature coil due to the interaction of these magnetic fields and performs a power generation operation. That is, the motor 8 serves as a generator and generates regenerative power. In addition, as a specific example in case a rotor is rotated by external force and regenerative electric power generate | occur | produces, there exist the rollback mentioned above, roll forward, etc.

The drive shaft of the motor 8 can be connected to the left and right rear wheels 10L, 10R via the speed reducer 26, the clutch 28, and the differential 30. Therefore, the motor 8 drives the driven wheel 10 constituted by the left and right rear wheels 10L and 10R in a state where the drive shaft of the motor 8 is connected to the left and right rear wheels 10L and 10R.
The clutch 28 is formed, for example, by a wet multi-plate clutch, and is interposed in a torque transmission path from the motor 8 to the left and right rear wheels 10L, 10R. In this embodiment, the clutch 28 as the fastening means is a wet multi-plate clutch. However, the present invention is not limited to this, and the clutch 28 may be a powder clutch or a pump-type clutch, for example.

In addition, the clutch 28 is in a connected state or a released state in accordance with a clutch control command output from the 4WD controller 14, and the vehicle driving state is set to a four-wheel driving state or a two-wheel driving state.
Specifically, when the clutch 28 is in a connected state, the drive shaft of the motor 8 is connected to the left and right rear wheels 10L, 10R, and the vehicle is brought into a four-wheel drive state. In this state, the left and right front wheels 2L, 2R and the left and right rear wheels 10L, 10R are used as driving wheels.

On the other hand, when the clutch 28 is in the released state, the connection between the drive shaft of the motor 8 and the left and right rear wheels 10L, 10R is released, and the vehicle is brought into a two-wheel drive state. In this state, only the left and right front wheels 2L, 2R are used as driving wheels.
The left and right rear wheels 10L and 10R are respectively provided with rear wheel speed sensors 32RL and 32RR.
Each rear wheel speed sensor 32RL, 32RR detects the rotational speed and rotational speed of the corresponding left and right rear wheels 10L, 10R, and outputs an information signal including the detected rotational speed and rotational speed to the 4WD controller 14. .

FIG. 2 is a diagram illustrating a configuration of the power electronics unit.
As shown in FIG. 2, the power electronics unit includes a generator 4, an inverter 6, a motor 8, a power consumption circuit 34, and a 4WD controller 14.
The generator 4 is connected to the inverter 6 via a rectifier 36 and has a generator-side field circuit 38.
Between the rectifier 36 and the inverter 6, a generator current sensor 40, a DC current sensor 42 and a DC voltage sensor 44 are arranged.
Specifically, the generator current sensor 40 is disposed between the generator 4 and the power consumption circuit 34.

The generator current sensor 40 detects the current supplied from the generator 4 to the input side of the inverter 6, that is, the current generated by the generator 4 (generator current Igen), and the generator current Igen is detected. An information signal including the magnitude is output to the 4WD controller 14.
Specifically, the DC current sensor 42 is disposed between the power consumption circuit 34 and a capacitor 46 described later.

  The direct current sensor 42 detects a direct current Idc between the power consumption circuit 34 and the capacitor 46, that is, on the direct current side of the inverter 6, and outputs an information signal including the magnitude of the detected direct current Idc to 4WD. Output to the controller 14. In the following description, the DC current Idc when regenerative power is generated, that is, the DC current flowing from the DC side of the inverter 6 to the generator 4 side is referred to as “regenerative DC current rIdc”.

The regenerative DC current rIdc is a current of power exceeding the sum of the power consumed by the internal loss composed of the loss of the inverter 6 and the motor 8 and the capacity of the capacitor 46 among the regenerative power generated by the motor 8. is there. In the following description, description regarding the capacitance of the capacitor 46 is omitted.
Specifically, the DC voltage sensor 44 is disposed between the capacitor 46 and the inverter 6.

The DC voltage sensor 44 detects a DC voltage Vdc between the capacitor 46 and the inverter 6, that is, on the DC side of the inverter 6, and outputs an information signal including the magnitude of the detected DC voltage Vdc to the 4WD controller 14. Output to. In the following description, the DC voltage Vdc when regenerative power is generated is referred to as “regenerative DC voltage rVdc”.
The regenerative DC voltage rVdc is a voltage of the regenerative power generated by the motor 8 that exceeds the power that can be consumed by the internal loss composed of the losses of the inverter 6 and the motor 8.

A capacitor 46 is installed in parallel on the DC side (input circuit) of the inverter 6. Thus, a capacitor input type circuit is formed.
A motor 8 is connected to the AC side (output circuit) of the inverter 6, and a V-phase current sensor 48 and a W-phase current sensor 50 are arranged between the AC side of the inverter 6 and the motor 8. .

The V-phase current sensor 48 detects a V-phase current output from the AC side of the inverter 6 to the motor 8 and outputs an information signal including the detected magnitude of the V-phase current to the 4WD controller 14.
The W-phase current sensor 50 detects a W-phase current output from the AC side of the inverter 6 to the motor 8 and outputs an information signal including the detected magnitude of the W-phase current to the 4WD controller 14.
The generator-side field circuit 38 includes a constant voltage power supply 52 and a generator-side field coil 54, and the generator field current Ifg is large according to the generator control signal output from the 4WD controller 14. To control. In the present embodiment, a 14V battery mounted on the vehicle is used as the constant voltage power source 52.

  The generator-side field circuit 38 is configured to select the output voltage (system voltage) of the constant voltage power supply 52 or the generator 4 itself as the field current power supply. As a result, the anode side of the field current power source is connected to the generator-side field coil 54 to perform switching of the transistor (not shown). In this case, in a state where the system voltage Vs is lower than the battery voltage Vb, it becomes a separate excitation region and uses the battery voltage Vb as a power source for the generator-side field coil 54. On the other hand, when the system voltage Vs becomes equal to or higher than the battery voltage Vb, such as when the output of the generator 4 is increased, the output voltage Vg of the generator 4 is selected as a self-excited region, and the generator side field coil is selected. The power source is 54. That is, it is possible to prevent the field power supply voltage from becoming 0 [V] by using the larger one of the system voltage Vs and the battery voltage Vb as the power supply voltage. Moreover, since the value of the generator field current Ifg can be increased according to the system voltage, the generator output can be significantly increased.

The motor 8 has a motor-side field circuit 56, and a resolver 58 is connected to its drive shaft.
The motor-side field circuit 56 includes a motor-side field coil 60, and controls the motor field current Ifm flowing in the motor-side field circuit 56 using the voltage generated by the generator 4 as a power source. Moreover, the motor side field circuit 56 shares the constant voltage power source 52 with which the generator side field circuit 38 is provided as a constant voltage power source.

Similarly to the generator-side field circuit 38, the motor-side field circuit 56 employs a configuration in which the constant voltage power supply 52 or the system voltage Vs is selected as the field current power supply. As a result, similarly to the generator-side field circuit 38, the larger one of the system voltage Vs and the battery voltage Vb is used as the power supply voltage, thereby preventing the field power supply voltage from becoming 0 [V]. To do.
The configuration of the motor-side field circuit 56 includes a known H-bridge circuit and can handle a case where a reverse voltage is applied to the motor-side field circuit 56 by a motor control signal output from the 4WD controller 14. To do.

The resolver 58 detects the rotation angle position θ of the rotor of the motor 8 and outputs an information signal including the detected rotation angle position θ to the 4WD controller 14.
The motor side field coil 60 is provided with a motor field current sensor 62.
The motor field current sensor 62 detects the motor field current Ifm flowing through the motor-side field circuit 56 and outputs an information signal including the magnitude of the detected motor field current Ifm to the 4WD controller 14.
The power consumption circuit 34 is electrically connected in parallel with the inverter between the generator 4 and the inverter 6.
The power consumption circuit 34 includes a power consumption unit 64 and a switching unit 66.
The power consumption unit 64 is, for example, a resistor. When power such as regenerative power is energized, the power consumption unit 64 converts this power into Joule heat and consumes it.

The switching unit 66 is, for example, a switching element, and switches to an energized state or a non-energized state in accordance with a switching signal output from a switching control unit 68 described later.
The switching unit 66 connects the DC side of the inverter 6 and the power consuming unit 64 in the energized state, and disconnects the connection between the DC side of the inverter 6 and the power consuming unit 64 in the non-energized state.
The 4WD controller 14 is configured to include an arithmetic processing device such as a microcomputer, for example. The configuration of the 4WD controller 14 will be described later.

The configuration of the 4WD controller 14 will be described below with reference to FIGS. 1 and 2 and FIGS. 3 to 9.
FIG. 3 is a block diagram showing details of the 4WD controller 14.
As shown in FIG. 3, the 4WD controller 14 includes a target motor torque calculation unit 14A, a generator supply power calculation unit 14B, a regenerative power generation determination unit 14C, and a regenerative power supply unit 14D. Further, the 4WD controller 14 includes a motor control unit 14E, a voltage command value control unit 14F, a generated current command calculation unit 14G, and a generated power amount control unit 14H.

The target motor torque calculation unit 14A calculates a motor based on a wheel speed difference between the main driving wheel 2 and the driven wheel 10 calculated based on wheel speed signals of the main driving wheel 2 and the driven wheel 10 and an accelerator pedal opening. Torque command value Tr * is calculated. That is, the target motor torque calculation unit 14A calculates the torque of the motor 8 that is required when the driven wheel 10 is driven.
Then, the target motor torque calculation unit 14A outputs the calculated motor torque command value Tr * to the generator supply power calculation unit 14B, the motor control unit 14E, and the power generation amount control unit 14H.

The generator supply power calculation unit 14B calculates the generator supply power Pg according to the following equation (1) based on the motor torque command value Tr * and the motor rotation speed Nm. That is, the generator supply power calculation unit 14 </ b> B calculates the necessary power that the generator 4 should generate when driving the driven wheel 10. The motor rotation speed Nm is obtained based on an information signal including the rotation angle position θ detected by the resolver 58, for example.
Pg = Tr * × Nm / Иm (1)
Here, Иm is the inverter efficiency. That is, the generator supply power Pg is greater by the inverter efficiency Иm than the electric power Pm (= Tr * × Nm) required for the motor, which is obtained by the product of the torque command value Tt and the motor rotation speed Nm. Become.
Then, the generator supply power calculation unit 14B outputs the calculated generator supply power Pg to the generation current command calculation unit 14G.

  The regenerative power generation determination unit 14C determines whether the behavior of the vehicle is rollback or rollforward based on the motor rotation speed Nm and the shift position. Then, the determination result is output to the regenerative power supply unit 14D. As a specific example, when the shift position is a forward side such as “D range” and the motor rotational speed Nm is a negative side (reverse side), it is determined that the behavior of the vehicle is a rollback.

  That is, the regenerative power generation determination unit 14C determines whether or not a regenerative current is generated, and outputs the determination result to the regenerative power supply unit 14D. For the shift position, for example, the transmission 18 is provided with a shift position detection sensor that detects the current shift position and outputs an information signal including the detected shift position to the 4WD controller 14. And based on the information signal which this shift position detection sensor output, a shift position is calculated | required.

FIG. 4 is a block diagram showing details of the regenerative power supply unit 14D.
As shown in FIG. 4, the regenerative power supply unit 14 </ b> D includes a power determination unit 70 and a switching control unit 68.
When receiving the determination result that the regenerative current is generated from the regenerative power generation determination unit 14C, the power determination unit 70 determines whether the regenerative power generated by the motor 8 is equal to or greater than the internal loss. Then, the determination result is output to the switching control unit 68.
Specifically, when the regenerative DC current rIdc is 0 A or more, it is determined that the regenerative power is greater than the internal loss, and when the regenerative DC current rIdc is less than 0 A, the regenerative power is less than the internal loss. judge.

  When the switching control unit 68 receives a determination result from the power determination unit 70 that the regenerative power is equal to or greater than the internal loss, the switching control unit 68 generates an information signal for switching the switching unit 66 to the energized state. Then, the generated information signal is output to the switching unit 66, the motor control unit 14E, the voltage command value control unit 14F, the generated current command calculation unit 14G, and the generated power amount control unit 14H. In the present embodiment, a case will be described in which the switching control unit 68 outputs the information signal for switching the switching unit 66 to the energized state and then does not perform duty control on the information signal. That is, in the present embodiment, a case will be described in which the switching control unit 68 does not perform duty control of the switching unit 66 in a state where the switching unit 66 is switched to the energized state.

The switching unit 66 that has received the information signal for switching the switching unit 66 to the energized state switches to the energized state and connects the DC side of the inverter 6 and the power consuming unit 64.
Here, as described above, the power determination unit 70 determines that the regenerative power is equal to or greater than the internal loss, and the switching control unit 68 outputs an information signal for switching the switching unit 66 to the energized state, so that the switching unit 66 In general, a response delay occurs until the power supply state becomes energized. In this case, before energizing the regenerative power to the power consumption unit 64, the regenerative power flows from the power consumption circuit 34 to the generator 4 side.

  Therefore, in the present embodiment, a threshold value (hereinafter, referred to as “regenerative DC current threshold value rIdc_siki”) that is 0 A or more is set in advance. Then, the regenerative DC current threshold rIdc_siki and the regenerative DC current rIdc are compared to determine whether the regenerative power is equal to or greater than the internal loss. The regenerative DC current threshold rIdc_siki is, for example, about 5A to 10A.

On the other hand, when receiving the determination result that the regenerative power is less than the internal loss, the switching control unit 68 generates an information signal for switching the switching unit 66 to the non-energized state. Then, the generated information signal is output to the switching unit 66, the motor control unit 14E, the voltage command value control unit 14F, the generated current command calculation unit 14G, and the generated power amount control unit 14H.
The switching unit 66 that has received the information signal for switching the switching unit 66 to the non-energized state switches to the non-energized state, and disconnects the connection between the DC side of the inverter 6 and the power consuming unit 64.
As described above, the switching control unit 68 switches the switching unit 66 to the energized state or the non-energized state according to the regenerative DC current rIdc.

Hereinafter, the operation of the above-described regenerative power supply unit 14D will be described with reference to FIG.
FIG. 5 is a flowchart showing the operation of the regenerative power supply unit 14D.
As shown in FIG. 5, the operation of the regenerative power supply unit 14D starts when the power determination unit 70 receives the determination result that the regenerative current is generated from the regenerative power generation determination unit 14C ( start).
The power determination unit 70 that has received the determination result that the regenerative current is generated determines whether or not the regenerative power is equal to or greater than the internal loss, and outputs the determination result to the switching control unit 68 (step S10). ).
The processing in step S10 also serves as processing for determining whether or not a flag for starting control of the power consumption circuit 34 (“power consumption circuit control start flag” shown in FIG. 5) is established.

If the power determination unit 70 determines that the regenerative power is greater than or equal to the internal loss, the determination result is output to the switching control unit 68 and the power consumption circuit control start flag is determined to be established (Yes).
The switching control unit 68 that has received the determination result that the regenerative power is greater than or equal to the internal loss generates an information signal for switching the switching unit 66 to the energized state (“power consumption circuit SW: ON” shown in FIG. 5). And this information signal is output to the switching part 66 (step S12).

At this time, the switching control unit 68 does not duty control the switching unit 66 in a state where the switching unit 66 is switched to the energized state.
After the switching control unit 68 outputs an information signal for switching the switching unit 66 to the energized state, the process of the regenerative power supply unit 14D returns to the process of step S10 (return).
On the other hand, when the power determination unit 70 determines that the regenerative power is less than the internal loss, the determination result is output to the switching control unit 68 and the power consumption circuit control start flag is not established (No). To do.

The switching control unit 68 that has received the determination result that the regenerative power is less than the internal loss generates an information signal for switching the switching unit 66 to the non-energized state (“power consumption circuit SW: OFF” shown in FIG. 5). . And this information signal is output to the switching part 66 (step S14).
After the switching control unit 68 outputs an information signal for switching the switching unit 66 to the non-energized state, the process of the regenerative power supply unit 14D returns to the process of step S10 (return).

FIG. 6 is a block diagram showing details of the motor control unit 14E.
As shown in FIG. 6, the motor control unit 14E includes a motor field power generation command value calculation unit 100, a multiplication unit 102, a motor side feedback control unit 104, a motor side PI control unit 106, and a motor side duty control. Part 108.
The motor control unit 14E operates when receiving an information signal for switching the switching unit 66 to the energized state from the regenerative power supply unit 14D.
In the motor field power generation command value calculation unit 100, the motor rotation speed Nm and the motor torque command value Tr * calculated by the target motor torque calculation unit 14A are applied to a previously stored motor field power generation command value characteristic map. Then, the motor field power generation command value If * is calculated. Then, the calculated motor field power generation command value If * is output to the motor-side feedback control unit 104.

FIG. 7 is a diagram illustrating an example of a motor field power generation command value characteristic map when regenerative power is generated.
As shown in FIG. 7, the motor field power generation command value characteristic map is a map that defines the relationship among the power (generated power) generated by the generator 4, the motor rotation speed Nm, and the motor torque command value Tr *. It is. In the present embodiment, a map in a state where the motor torque is constant is used.
Regarding the relationship between the generated power and the motor rotation speed Nm, in the region where the regenerative power is generated, the generated power increases as the rotation speed decreases (increases to the negative side). When the increased generated power becomes the generated power threshold, the generated power becomes a constant value. Here, the generated power threshold is set according to the power required when driving the driven wheels 10 when the behavior of the vehicle shifts from a state where regenerative power is generated to powering.

Returning to the description with reference to FIG.
Multiplier 102 multiplies generator current Igen and regenerative DC voltage rVdc, and outputs the result of multiplication to motor-side feedback controller 104.
The motor-side feedback control unit 104 calculates a deviation between the motor field power generation command value If * and the multiplication result output from the multiplication unit 102 by feedback control. The calculated deviation is used as the motor-side PI control unit 106. Output to.

The motor-side PI control unit 106 performs PI control on the deviation calculated by the motor-side feedback control unit 104 and then outputs this deviation to the motor-side duty control unit 108.
The motor-side duty control unit 108 performs duty control using the regenerative DC voltage rVdc on the deviation for which PI control is performed, and generates a motor torque command value. The generated motor torque command value is output to the motor side field circuit 56.
As described above, when the regenerative electric power is generated and the switching unit 66 is switched to the energized state, the motor control unit 14E applies the motor 8 to the motor 8 so that the torque of the motor 8 becomes the torque calculated by the target motor torque calculation unit 14A. Controls the torque command value.

Hereinafter, operations of the above-described regenerative power generation determination unit 14C, regenerative power supply unit 14D, and motor control unit 14E will be described with reference to FIG.
FIG. 8 is a flowchart illustrating operations of the regenerative power generation determination unit 14C, the regenerative power supply unit 14D, and the motor control unit 14E.
As shown in FIG. 8, the operations of the regenerative power generation determination unit 14C, the regenerative power supply unit 14D, and the motor control unit 14E determine whether or not the regenerative current generation unit 14C generates a regenerative current. Start from the moment (Start). In FIG. 8, it is determined whether or not a regenerative current is generated by using whether or not the behavior of the vehicle is rollback ("rollback operation" shown in FIG. 8). The case is illustrated.

In step S20, the regenerative power generation determination unit 14C determines whether or not the behavior of the vehicle is a rollback. And when it determines with the behavior of a vehicle being rollback, this determination result is output to the electric power determination part 70 with which regenerative electric power supply part 14D is provided.
On the other hand, if the regenerative power generation determination unit 14C determines in step S20 that the behavior of the vehicle is not rollback, the determination result is output to the power determination unit 70 included in the regenerative power supply unit 14D, and then step S20. Return to processing (return).

In step S22, the power determination unit 70 that has received the determination result that the vehicle behavior is rollback compares the regenerative DC current threshold rIdc_siki with the regenerative DC current rIdc, and determines whether or not the regenerative power is greater than or equal to the internal loss. Judgment is made. When it is determined that the regenerative DC current threshold rIdc_siki is equal to or greater than the regenerative DC current rIdc and the regenerative power is equal to or greater than the internal loss, this determination result is output to the switching control unit 68.
On the other hand, when determining that the regenerative DC current threshold rIdc_siki is less than the regenerative DC current rIdc and the regenerative power is less than the internal loss in step S22, the power determination unit 70 outputs the determination result to the switching control unit 68. .

  The switching control unit 68 that has received the determination result that the regenerative power is equal to or greater than the internal loss generates an information signal for switching the switching unit 66 to the energized state in step S24. Then, this information signal is output to the switching unit 66 and the motor control unit 14E (“power consumption circuit control start” shown in FIG. 8). At this time, the switching control unit 68 does not duty control the switching unit 66 in a state where the switching unit 66 is switched to the energized state.

The switching unit 66 that has received the information signal for switching the switching unit 66 to the energized state switches to the energized state and connects the DC side of the inverter 6 and the power consuming unit 64. The power consuming unit 64 converts the regenerative power energized through the switching unit 66 into Joule heat and consumes it.
On the other hand, the switching control unit 68 that has received the determination result that the regenerative power is less than the internal loss generates an information signal for switching the switching unit 66 to the non-energized state in step S26. Output to. Thereafter, the process returns to step S20 (return).

  The switching unit 66 that has received the information signal for switching the switching unit 66 to the non-energized state switches to the non-energized state, and disconnects the connection between the DC side of the inverter 6 and the power consuming unit 64. Thereby, in a state where the behavior of the vehicle is rollback, the regenerative power is consumed by the internal loss without using the power consumption unit 64 ("rollback operation with internal loss" shown in FIG. 8). .

  In step S28, the motor control unit 14E that has received the information signal for switching the switching unit 66 to the energized state generates a motor torque command value ("rollback power generation control start" shown in FIG. 8). The generated motor torque command value is output to the motor side field circuit 56. After outputting the motor torque command value to the motor-side field circuit 56, the process returns to step S20 (return).

Similarly to the motor control unit 14E, the voltage command value control unit 14F operates when receiving an information signal for switching the switching unit 66 to the energized state from the regenerative power supply unit 14D. Then, the voltage command value to the generator 4 is controlled so that the regenerative DC voltage rVdc exceeds the induced voltage of the motor 8.
Specifically, the amount of decrease in the regenerative DC voltage rVdc after the switching unit 66 is energized, the amount of increase in the regenerative DC voltage rVdc before the switching unit 66 is energized, and the induced voltage of the motor 8. Thus, the generated voltage command value Vdc * for the generator 4 is calculated. The calculated power generation voltage command value Vdc * is output to the generator 4.

  Note that, as described above, the voltage command value control unit 14F performs the above operation when the switching control unit 68 does not perform duty control of the switching unit 66 while the switching unit 66 is switched to the energized state. On the other hand, when the switching control unit 68 performs duty control on the switching unit 66 while the switching unit 66 is switched to the energized state, a different operation is performed. The operation of the voltage command value control unit 14F when the switching control unit 68 performs duty control of the switching unit 66 while the switching unit 66 is switched to the energized state will be described later.

Hereinafter, the reason why the voltage command value to the generator 4 is controlled by the voltage command value control unit 14F so that the regenerative DC voltage rVdc exceeds the induced voltage of the motor 8 will be described with reference to FIG.
FIG. 9 shows an operating point of the generator current Igen (hereinafter referred to as “generator current”) and the DC voltage Vdc (hereinafter simply referred to as “operating point”) in a state where the switching unit 66 is energized. It is a figure which shows a motion. The horizontal axis shown in FIG. 9 is the generator current, and the vertical axis is the DC voltage Vdc. Further, a plurality of straight lines A shown in FIG. 9 are paths along which the operating point moves when the field current of the generator is constant.

As shown in FIG. 9, when the switching unit 66 is energized at a point where the voltage command value to the generator is low and the DC voltage Vdc is low (LowP1 shown in FIG. 9), the operating point moves and the generator As the current increases, the DC voltage Vdc decreases. Then, the reduced DC voltage Vdc converges at a convergence operating point on the resistance value (LowR1 shown in FIG. 9).
In this state, since the reduced DC voltage Vdc is less than the induced voltage of the motor 8, the control of the motor 8 serving as the generator fails.

  On the other hand, when the voltage command value to the generator 4 is controlled by the voltage command value control unit 14F as in this embodiment, the DC voltage Vdc is higher than the point lowP1 where the DC voltage Vdc is low (in FIG. 9). In HiP1), the switching unit 66 is energized. This is because the DC voltage Vdc increases during the response delay that occurs until the switching control unit 68 outputs the information signal for switching the switching unit 66 to the energized state and the switching unit 66 enters the energized state.

When the switching unit 66 is energized at a point HiP1 where the DC voltage Vdc is higher than lowP1, the operating point moves, the generator current increases, and the DC voltage Vdc decreases. The reduced DC voltage Vdc converges at a convergence operating point (HiR1 shown in FIG. 9) where the DC voltage Vdc is higher than LowR1.
In this state, since the reduced DC voltage Vdc is equal to or higher than the induced voltage of the motor 8, it is possible to prevent the control of the motor 8 serving as the generator from failing.

Similarly to the motor control unit 14E, the generated current command calculation unit 14G operates when receiving an information signal for switching the switching unit 66 to the energized state from the regenerative power supply unit 14D. And the electric power generation command value to the generator 4 is controlled so that the electric power which the generator 4 generates becomes the generator supply electric power Pg.
Specifically, first, based on the generator supply power Pg calculated by the generator supply power calculation unit 14B and the generated voltage command value Vdc * calculated by the voltage command value control unit 14F, the current command value idc * Calculation is performed by the following equation (2).
Idc * = Pg / Vdc * (2)

Then, the current command value idc * calculated by the above equation (2) is output to the generator 4 as a generator control signal.
Similarly to the motor control unit 14E, the power generation amount control unit 14H operates when receiving an information signal for switching the switching unit 66 to the energized state from the regenerative power supply unit 14D. And the electric power generation amount of the generator 4 is controlled so that the electric power which the generator 4 generates does not exceed the electric power which can be consumed by the power consumption circuit 34 and an internal loss.

Specifically, in response to the generator current Igen and the regenerative DC current rIdc, a power generation stop signal for stopping power generation is output to the generator 4 so that the generator current Igen does not exceed the regenerative DC current rIdc. The state where the generator current Igen exceeds the regenerative DC current rIdc is a state where the power generated by the generator 4 is supplied to the power consuming unit 64 in addition to the regenerative power.
The target motor torque calculator 14A as described above constitutes a torque calculator that calculates the torque of the motor 8 that is required when the driven wheel 10 is driven.

Further, the generator supply power calculation unit 14B as described above constitutes a power calculation unit that calculates the necessary power that the generator 4 should generate when the driven wheel 10 is driven.
Further, the power consumption circuit 34 and the regenerative power supply unit 14D as described above constitute regenerative power consumption means for consuming the regenerative power generated by the motor 8 on the motor 8 side rather than the generator 4.
Further, the motor control unit 14E as described above constitutes a torque control unit that controls the torque command value to the motor 8 so that the torque of the motor 8 becomes the torque calculated by the target motor torque calculation unit 14A. Yes.

Further, the voltage command value control unit 14F as described above constitutes voltage command value control means for controlling the voltage command value to the generator 4 so that the regenerative DC voltage rVdc exceeds the induced voltage of the motor 8. Yes.
In addition, the generated current command calculation unit 14G as described above generates power to the generator 4 so that the power generated by the generator 4 becomes the necessary power to be generated by the generator 4 when the driven wheels 10 are driven. Power generation command value control means for controlling the command value is configured.

(Operation)
Next, the operation of the regenerative power control device will be described with reference to FIGS. 10 and 11 with reference to FIGS. In addition, the following description is mainly demonstrated using FIG.
FIG. 10 is a time chart showing the behavior of the motor 8 and the power electronics unit when the vehicle is traveling. In addition, the graph shown in FIG. 10 shows the behavior of the motor speed (Motor speed), the motor torque (Trueque), and the direct current (DC Current) from the top. Furthermore, the graph shown in FIG. 10 shows the behaviors of DC power (Power), DC voltage (DC Voltage), and generator field current from the top, respectively.

In the present embodiment, as an example, a case where the motor torque and the generator field current are controlled to a constant value will be described. In the present embodiment, as an example, a case where the regenerative DC current threshold rIdc_siki is set to 0A will be described.
FIG. 11 is a diagram showing movements of the operating points of the generator current and the DC voltage Vdc that are linked with a part of the time chart of FIG. Note that the horizontal axis, the vertical axis, and the plurality of straight lines A shown in FIG. 11 indicate the same elements as those shown in FIG. In FIG. 11, unlike FIG. 9, an “overvoltage threshold” in which the increased voltage causes the control failure is shown.

The time chart of FIG. 10 starts from a time point (“t0” shown in the figure) when the vehicle is running in a power running state.
When the vehicle is running in a power running state, for example, when the accelerator pedal is depressed or the brake pedal is depressed, and the vehicle speed decreases, the motor speed decreases (increases negative). .
At this time, since the motor output (“ωT: motor output” shown in the “DC power” column) decreases as the motor speed decreases, the DC current Idc (“DC current: Idc” shown in the “DC current” column). ) Decreases. In this state, the motor output is less than the internal loss (“motor + inverter power consumption: (Rs + Ron) Im ² ” shown in the “DC power” column).

  Further, in the above state, the rotational speed of the engine 1 decreases as the vehicle speed decreases, so the generator current Igen (“generator current: Igen” shown in the “DC current” column) decreases. As a result, the generator power composed of the DC voltage Vdc and the generator current Igen (“generator power: Vdc × Igen” shown in the “DC power” column) decreases. Further, since the direct current Idc and the generator current Igen decrease, the direct current voltage Vdc increases.

  Then, the motor rotation speed decreases, the rotation speed of the motor 8 becomes 0 rpm (“t1” shown in the figure), and further, when the vehicle moves backward (rollback), the rotation speed of the motor 8 decreases from 0 rpm. . Then, the rotation speed of the motor 8 becomes a negative rotation speed, the motor output increases, and the motor 8 becomes a generator to generate regenerative power. Further, when the rotational speed of the motor 8 becomes a negative rotational speed, the regenerative braking force by the motor 8 increases as the rotational speed increases.

If the rollback continues and the rotational speed of the motor 8 to the negative side increases, the motor output increases. For this reason, regenerative electric power increases and approaches internal loss. In this state, while the regenerative power is less than the internal loss, the regenerative power is consumed with the internal loss, so that the regenerative power can be prevented from flowing to the generator 4 side from the power consumption circuit 34.
Further, when the motor 8 becomes a generator and generates regenerative power, the regenerative power generation determination unit 14C outputs a determination result that a regenerative current is generated to the regenerative power supply unit 14D.

In the regenerative power supply unit 14D that has received the determination result that the regenerative current is generated, the power determination unit 70 determines whether the regenerative power is equal to or greater than the internal loss. The power determination unit 70 that has determined whether or not the regenerative power is equal to or greater than the internal loss outputs the determination result to the switching control unit 68.
Here, while the regenerative power is less than the internal loss (“t1 → t2” shown in FIGS. 10 and 11), the power determination unit 70 switches and controls the determination result that the regenerative power is less than the internal loss. Since it outputs to the part 68, the switching part 66 will be in a non-energized state.

Further, in the above state, since the rotational speed of the engine 1 is decreased from the time “t1”, the generator current Igen and the generator power are decreased from the time “t1”. Further, since the direct current Idc and the generator current Igen are decreased from the time “t1”, the direct current voltage Vdc is increased from the time “t1”.
As a result, the DC voltage Vdc increased with the decrease in the generator current Igen approaches the overvoltage threshold, and the generator current decreases (see FIG. 11).
When the rotational speed to the negative side of the motor 8 increases and the motor output increases, the power determination unit 70 determines that the regenerative power is internal when the regenerative power becomes equal to the internal loss ("t2" in the figure). It is determined that the loss is greater than or equal to the loss, and the determination result is output to the switching control unit 68.

  The switching control unit 68 that has received the determination result that the regenerative power is equal to or greater than the internal loss outputs an information signal for switching the switching unit 66 to the energized state to the switching unit 66, the motor control unit 14E, and the voltage command value control unit 14F. To do. In addition to this, the switching control unit 68 that has received the determination result that the regenerative power is greater than or equal to the internal loss sends an information signal for switching the switching unit 66 to the energized state to the generated current command calculation unit 14G and the generated power amount control unit 14H. Output.

  Then, the switching unit 66 that has received the information signal for switching the switching unit 66 to the energized state switches to the energized state and connects the DC side of the inverter 6 and the power consuming unit 64. As a result, the regenerative power is supplied to the power consuming unit 64 via the switching unit 66. The power consuming unit 64 converts the regenerative power energized through the switching unit 66 into Joule heat and consumes it.

Accordingly, the regenerative power is consumed by the power consumption unit 64 in addition to the internal loss, and the total regenerative power consumption (“total loss: (motor + inverter power consumption) + discharge shown in the“ DC power ”column) Resistance loss ") increases.
The motor control unit 14E that has received the information signal for switching the switching unit 66 to the energized state sets the torque command value to the motor 8 so that the torque of the motor 8 becomes the torque calculated by the target motor torque calculation unit 14A. Control.

  Furthermore, the voltage command value control unit 14F that has received the information signal for switching the switching unit 66 to the energized state controls the voltage command value to the generator 4 so that the regenerative DC voltage rVdc exceeds the induced voltage of the motor 8. Accordingly, during “t2 → t3” shown in FIG. 10 and FIG. 11, the DC voltage Vdc increases from the time of “t2”, so that the DC current Idc and the generator current Igen are at the time of “t2”. Less than.

  Further, the generated current command calculation unit 14G that has received the information signal for switching the switching unit 66 to the energized state sets the power generation command value to the generator 4 so that the power generated by the generator 4 becomes the generator supply power Pg. Control. As a result, the generator current Igen is reduced so that the electric power generated by the generator 4 becomes the necessary electric power that the generator 4 should generate when driving the driven wheels 10. Prevents 0A.

For this reason, the generator current Igen increases and the DC voltage Vdc decreases. At this time “t2”, all of the increase in the generator current Igen is energized to the power consuming unit 64.
As the generator current Igen increases, the generator power also increases. The increase in generator power is the amount of regenerative power consumed by the power consuming unit 64 and the amount of increase in the total consumption of regenerative power. Therefore, the regenerative power flows from the power consumption circuit 34 to the generator 4 side. Can be prevented.

As described above, as the generator current Igen increases, the DC voltage Vdc decreases in a direction away from the overvoltage threshold, and the generator current increases (see FIG. 11).
When the regenerative power becomes equal to the internal loss, the rollback continues from the time “t2”, the rotation speed to the negative side of the motor 8 increases, and the motor output increases. The current (“discharge generator current: Ir” shown in the figure) increases. In this state, since the rotation speed of the engine 1 is decreased from the time “t2”, the generator current Igen and the generator power are decreased from the time “t2”.

In the above state, the total consumption of regenerative power increases as the motor output increases and the generator power decreases. For this reason, it becomes possible to prevent the regenerative power from flowing to the generator 4 side from the power consumption circuit 34.
As a result, the DC voltage Vdc increases along the resistance of the power consumption unit 64 and the generator current increases as the total consumption of regenerative power increases (see FIG. 11).

When the rollback is continued and the regenerative braking force of the motor 8 is increased, the rollback is stopped and the behavior of the vehicle is stopped, at the time when the rollback stops ("t3" in the figure), the motor The increase of the rotation speed to the negative side stops.
When the increase in the motor rotation speed to the negative side is stopped, an increase in the regenerative power flowing through the power consuming unit 64, a decrease in the generator current Igen and the generator power, an increase in the DC voltage Vdc, and a decrease in the DC current Idc. Stop.

At this time, the generated current command calculation unit 14G generates the power generation command value to the generator 4 so that the generator current Igen and the generator power become the necessary power to be generated by the generator 4 when the driven wheel 10 is driven. Is controlling. For this reason, the electric power generated by the generator 4 maintains the necessary electric power that the generator 4 should generate when the driven wheel 10 is driven.
In this state, the value at which the decrease of the DC voltage Vdc stops (convergence voltage) varies depending on the regenerative power supplied to the power consuming unit 64 (see FIG. 11). That is, in the section from “t3” to “t4” shown in FIGS. 10 and 11, the convergence voltage varies depending on the amount of regenerative power.

Further, since the increase in the motor output and the decrease in the generator power Igen are stopped, the increase in the total consumption of the regenerative power is stopped, and a value corresponding to the motor output and the generator power Igen is held. For this reason, it becomes possible to prevent the regenerative power from flowing to the generator 4 side from the power consumption circuit 34.
When the driving force of the engine 1 is transmitted to the main drive wheel 2 at the time when the accelerator pedal is depressed ("t4" in the figure) when the rollback is stopped, the behavior of the vehicle is in the power running state. Migrate to

In this state, the rotation speed of the engine 1 increases and the generator current Igen increases. Moreover, since the rotation speed to the negative side of the motor 8 decreases and the motor output as a generator decreases, the regenerative power supplied to the power consuming unit 64 decreases and approaches an internal loss.
At this time, the generated current command calculation unit 14G generates a power generation command value to the generator 4 so that the generator current Igen and the generator power become necessary power that the generator 4 should generate when the driven wheel 10 is driven. Is controlling. Therefore, the generator current Igen increases without lowering the required power to be generated by the generator 4 when the driven wheel 10 is driven, and the torque of the motor 8 can be stably output.

In this state, the DC voltage Idc increases because the DC voltage Vdc decreases. Moreover, since the direct current Idc and the generator current Igen increase, the generator power increases.
Further, the total consumption of regenerative power decreases as the motor output decreases and the generator power increases. Here, since the reduction degree of the motor output is larger than the increase degree of the generator power, the total consumption amount of the regenerative power is reduced. For this reason, it becomes possible to prevent the regenerative power from flowing to the generator 4 side from the power consumption circuit 34.
When the regenerative power decreases due to a decrease in the motor output and this regenerative power becomes less than the internal loss ("t5" in the figure), the power determination unit 70 determines that the regenerative power is less than the internal loss. The determination result is output to the switching control unit 68.

  Upon receiving the determination result that the regenerative power is less than the internal loss, the switching control unit 68 sends an information signal for switching the switching unit 66 to the non-energized state to the switching unit 66, the motor control unit 14E, and the voltage command value control unit 14F. Output. In addition to this, the switching control unit 68 that has received the determination result that the regenerative power is less than the internal loss outputs the information signal for switching the switching unit 66 to the non-energized state as the generated current command calculating unit 14G and the generated power amount control unit 14H. Output to.

The switching unit 66 that has received the information signal for switching the switching unit 66 to the non-energized state switches to the non-energized state, cuts off the connection between the DC side of the inverter 6 and the power consuming unit 64, and regenerates the power consuming unit 64. Shut off the power to the.
As a result, the regenerative power is consumed by internal loss without using the power consumption unit 64, and the total consumption of the regenerative power is reduced. In this state, since all the regenerative power is consumed due to the internal loss, it is possible to prevent the regenerative power from flowing to the generator 4 side from the power consumption circuit 34.

The motor control unit 14E that has received the information signal for switching the switching unit 66 to the non-energized state stops the control of the torque command value to the motor 8. As a result, the generator current Igen decreases and the DC voltage Vdc increases.
Then, the generator power decreases as the generator current Igen decreases. At this time, the decrease in the generator power is the consumption of the regenerative power that has been energized to the power consumption unit 64, and is the decrease in the total consumption of the regenerative power, so that the regenerative power is more than the power consumption circuit 34. It becomes possible to prevent the flow to the generator 4 side.

From the time “t5” when the regenerative power becomes less than the internal loss, when the rotational speed of the motor 8 to the negative side decreases and the motor output decreases, the rotational speed of the engine 1 increases from the time “t5”. For this reason, the generator current Igen and the generator power increase from the time “t5”.
Then, when the rotational speed of the motor 8 exceeds 0 rpm (“t6” in the figure), the driving force generated by the motor 8 is transmitted to the driven wheel 10 and the driven wheel 10 is driven. Thereby, the vehicle travels in a four-wheel drive state.

  As described above, in the regenerative power control device of the present embodiment, the power generated by the generator 4 while the regenerative power exceeds the internal resistance (between “t2” and “t5” shown in FIG. 10) When the driven wheels 10 are driven, the generator 4 becomes necessary power to be generated. That is, in the section of “discharge resistance ON => Vdc = Rdis × Ir” shown in FIGS. 10 and 11, the power generated by the generator 4 is the necessary power that the generator 4 should generate when driving the driven wheel 10. It becomes.

Hereinafter, the operation of the regenerative power control apparatus of the present embodiment and the operation of the regenerative power control apparatus of the conventional example will be compared using FIGS. 12 and 13 with reference to FIGS. 10 and 11.
FIG. 12 is a time chart showing the behavior of the motor 8 and the power electronics unit during traveling of the vehicle by the conventional regenerative power control device. The graph shown in FIG. 12 is the same as that shown in FIG. 10. In the following description, the motor torque and the generator field current are controlled to be constant values, and the regenerative DC current threshold rIdc_siki is set to 0A. The case will be described.

FIG. 13 is a diagram showing movements of the operating points of the generator current and the DC voltage Vdc that are linked with a part of the time chart of FIG. Note that the horizontal axis, the vertical axis, the plurality of straight lines A, and the overvoltage threshold shown in FIG. 13 indicate the same elements as those shown in FIG.
The time chart of FIG. 12 starts from a time point (“t0” shown in the figure) when the vehicle is running in a power running state.
When the vehicle is running in a power running state, for example, when the accelerator pedal is depressed or the brake pedal is depressed, and the vehicle speed decreases, the motor rotation speed decreases.

At this time, since the motor output decreases as the motor rotation speed decreases, the DC current Idc decreases. In this state, the motor output is less than the internal loss.
In the above state, the rotational speed of the engine 1 decreases as the vehicle speed decreases, so that the generator current Igen decreases and the generator power decreases. Further, since the direct current Idc and the generator current Igen decrease, the direct current voltage Vdc increases.

  From the time when the motor rotation speed decreases and the rotation speed of the motor 8 reaches 0 rpm ("t1" in the figure), when the vehicle further moves backward (rollback), the rotation speed of the motor 8 starts from 0 rpm. Decrease. Then, the rotation speed of the motor 8 becomes a negative rotation speed, the motor output increases, and the motor 8 becomes a generator to generate regenerative power. Further, when the rotational speed of the motor 8 becomes a negative rotational speed, the regenerative braking force by the motor 8 increases as the rotational speed increases.

If the rollback continues and the rotational speed of the motor 8 to the negative side increases, the motor output increases. For this reason, regenerative electric power increases and approaches internal loss. In this state, while the regenerative power is less than the internal loss (“t1 → t2” shown in FIGS. 12 and 13), all the regenerative power is consumed with the internal loss. It does n’t flow.
Further, in the above state, since the rotational speed of the engine 1 is decreased from the time “t1”, the generator current Igen and the generator power are decreased from the time “t1”. Further, since the direct current Idc and the generator current Igen are decreased from the time “t1”, the direct current voltage Vdc is increased from the time “t1”.

As a result, the DC voltage Vdc increased with the decrease in the generator current Igen approaches the overvoltage threshold, and the generator current decreases (see FIG. 13).
When the rotation speed to the negative side of the motor 8 increases and the motor output increases, the regenerative power exceeds the consumption due to the internal loss when the regenerative power exceeds the internal loss ("t2" shown in the figure). .
As a result, the regenerative power flows from the inverter 6 toward the generator 4, and the DC voltage Vdc increases and exceeds the overvoltage threshold (see FIG. 13).

When the DC voltage Vdc exceeds the overvoltage threshold, control failure (overvoltage failure) of the generator 4 and the motor 8 occurs due to the increased DC voltage Vdc, that is, regenerative power that flows from the inverter 6 to the generator 4 side.
As described above, in the regenerative power control device of the conventional example, it is necessary to suppress the power generation amount of the generator 4 within a range that can be consumed by the internal loss when the regenerative power is generated. For this reason, it is difficult to set the torque of the driven wheel 10 to a desired magnitude even when a large acceleration force such as climbing on a slope or starting on a slope is required.

(effect)
(1) In the regenerative power control apparatus for a vehicle according to the present embodiment, the switching unit is energized in accordance with the direct current on the direct current side of the inverter when regenerative power is generated, and the direct current side of the inverter and the power consumption unit are connected. .
For this reason, even if the regenerative power exceeds the internal loss, the regenerative power exceeding the internal loss can be consumed by the power consumption unit, and regenerative power can be prevented from flowing to the generator side from the power consumption circuit. It becomes. In addition, since the regenerative power exceeding the internal loss can be consumed by the power consumption unit, it is not necessary to suppress the power generation amount of the generator within a range that can be consumed by the internal loss.

In addition, when the current command value control means generates regenerative power and switches the switching unit to the energized state, the current command value to the generator is set so that the power generated by the generator becomes the power calculated by the power calculation means. To control.
As a result, it is possible to prevent the generator and motor from failing due to regenerative electric power, and to move from the state where regenerative electric power is generated to the state where the driven wheels are driven by the motor. The torque of the wheel can be set to a desired magnitude.
As described above, it is possible to improve the steering stability of the vehicle.

(2) Moreover, in the regenerative power control device for a vehicle according to the present embodiment, when the power determination unit determines that the regenerative power is equal to or greater than the internal loss, the switching control unit switches the switching unit to the energized state. On the other hand, when the power determination unit determines that the regenerative power is less than the internal loss, the switching control unit switches the switching unit to a non-energized state.
For this reason, before the regenerative power exceeds the internal loss, it becomes possible to connect the inverter to the DC side and the power consuming unit by energizing the switching unit, and the regenerative power exceeding the internal loss can be connected by the power consuming unit. It can be consumed.
As a result, it is possible to prevent the regenerative power from flowing to the generator side from the power consumption circuit, and it is possible to prevent the regenerative power from causing a control failure of the generator and the motor.
In addition, when shifting from a state in which regenerative power is generated to a state in which driven wheels are driven by a motor, it is possible to smoothly supply power generated by the generator to the motor.

(3) Further, in the regenerative power control device for a vehicle according to the present embodiment, when regenerative power is generated and the switching unit is switched to the energized state, the voltage command value control means causes the DC voltage to exceed the induced voltage of the motor. The voltage command value to the generator is controlled.
In addition, the voltage command value control means may cause the DC voltage to exceed the induced voltage of the motor according to the decrease amount of the DC voltage after the switching unit is energized and the increase amount of the DC voltage before the energization state. The voltage command value is controlled.
As a result, it is possible to prevent the generator and motor from failing due to regenerative electric power, so that it is possible to improve the steering stability of the vehicle.

(4) Further, in the regenerative power control device for a vehicle according to the present embodiment, when regenerative power is generated and the switching unit is switched to the energized state, the power generation command value control means is responsive to the generator current generated by the generator. The power generation command value is controlled.
As a result, the power generated by the generator can be stably supplied to the inverter, so that the steering stability of the vehicle can be improved.

(5) In the regenerative power control device for a vehicle according to the present embodiment, when the regenerative power is generated and the switching unit is switched to the energized state, the power generation amount control unit controls the power generation amount of the generator. Specifically, the power generation amount of the generator is controlled so that the power generated by the generator does not exceed the power that can be consumed by the power consumption unit and the internal loss.
For this reason, it becomes possible to suppress the electric power generation amount of a generator in the state which does not need to supply the electric power which a generator generates to an inverter, and it becomes possible to reduce the electric power which an electric power consumption part consumes.
As a result, it is possible to suppress the temperature rise that occurs in the power consuming unit, and it is possible to efficiently consume regenerative power in the power consuming unit, thereby prolonging the life of the power consuming unit. It becomes possible.

(Application example)
(1) In the regenerative power control device for a vehicle according to the present embodiment, the power determination unit uses a comparison between the regenerative DC current and the internal loss when determining whether the regenerative power is equal to or greater than the internal loss. However, the present invention is not limited to this. That is, when the power determination unit determines whether or not the regenerative power is greater than or equal to the internal loss, a comparison between the regenerative DC voltage and the voltage command value to the generator may be used.
Specifically, the regenerative DC voltage is compared with the generated voltage command value, and when the regenerated DC voltage is equal to or greater than the generated voltage command value, it is determined that the regenerative power is equal to or greater than the internal loss. On the other hand, when the regenerative DC voltage is less than the generated voltage command value, it is determined that the regenerative power is less than the internal loss.
In this case, the switching unit is switched to the energized state with the regenerative power exceeding the internal loss. For this reason, an overvoltage failure is prevented using data, such as sampling based on the measurement of DC voltage, and sampling based on the measurement of the operating condition of a switching part.

(2) Further, in the regenerative power control device for a vehicle according to the present embodiment, the switching control unit does not perform duty control of the switching unit in a state where the switching unit is switched to the energized state, but the present invention is not limited to this. Absent. That is, the switching control unit may perform duty control on the switching unit while the switching unit is switched to the energized state.
In this case, the regenerative power supply unit and the voltage command value control unit perform different operations from the case where the switching control unit switches the switching unit to the energized state and the switching unit is not duty controlled.
Specifically, the voltage command value is controlled so that the DC voltage exceeds the induced voltage of the motor in accordance with the DC voltage after the switching unit is energized. As a result, it is possible to prevent a sudden change in the operating point after the switching unit is energized.

Hereinafter, the configuration of the switching control unit 68 when the switching control unit 68 performs duty control of the switching unit 66 in a state where the switching unit 66 is switched to the energized state will be described with reference to FIG.
FIG. 14 is a block diagram illustrating details of the switching control unit 68 when the switching control unit 68 performs duty control of the switching unit 66 in a state where the switching unit 66 is switched to the energized state.

As shown in FIG. 14, the switching control unit 68 includes a switching-side feedback control unit 110, a switching-side PI control unit 112, and a switching-side duty control unit 114.
When the switching-side feedback control unit 110 receives the determination result that the regenerative power is greater than or equal to the internal loss, the switching side feedback control unit 110 calculates a deviation ΔVdc between the regenerative DC voltage rVdc and the voltage command value Vdc * by known feedback control. The calculated deviation ΔVdc is output to the switching side PI control unit 112.

When the switching-side PI control unit 112 receives a deviation ΔVdc between the regenerative DC voltage rVdc and the voltage command value Vdc *, the switching-side PI control unit 112 performs known PI control on the deviation ΔVdc. Then, the deviation ΔVdc subjected to the PI control is output to the switching duty control unit 114.
When the switching-side duty control unit 114 receives the deviation ΔVdc between the regenerative DC voltage rVdc subjected to PI control and the voltage command value Vdc *, the switching-side duty control unit 114 performs duty control on the deviation ΔVdc and switches the switching unit 66 to the energized state. Generate a signal. Then, the generated information signal is output to the switching unit 66, the motor control unit 14E, the voltage command value control unit 14F, the generated current command calculation unit 14G, and the generated power amount control unit 14H.
As described above, the switching control unit 68 performs duty control on the switching unit 66 while the switching unit 66 is switched to the energized state.

Next, the operation of the regenerative power supply unit 14D when the switching control unit 68 performs duty control on the switching unit 66 in a state where the switching unit 66 is switched to the energized state will be described with reference to FIG.
FIG. 15 is a flowchart illustrating the operation of the regenerative power supply unit 14D when the switching control unit 68 performs duty control of the switching unit 66 in a state where the switching unit 66 is switched to the energized state.
As shown in FIG. 15, the operation of the regenerative power supply unit 14D starts when the power determination unit 70 receives the determination result that the regenerative current is generated from the regenerative power generation determination unit 14C ( start).

The power determination unit 70 that has received the determination result that the regenerative current is generated determines whether or not the regenerative power is equal to or greater than the internal loss, and outputs the determination result to the switching control unit 68 (step S30). ).
Further, the processing in step S30 also serves as processing for determining whether or not a flag for starting control of the power consumption circuit 34 (“power consumption circuit control start flag” shown in FIG. 15) is established.

When the power determination unit 70 determines that the regenerative power is equal to or greater than the internal loss, the determination result is output to the switching control unit 68 and it is determined that the power consumption circuit control start flag is established.
The switching control unit 68 that has received the determination result that the regenerative power is equal to or greater than the internal loss generates an information signal that switches the switching unit 66 to the energized state. Then, the generated information signal is output to the switching unit 66 (step S32).

At this time, the switching control unit 68 performs duty control on the switching unit 66 in a state where the switching unit 66 is switched to the energized state (“power consumption circuit duty control” shown in FIG. 15).
After the switching control unit 68 outputs an information signal for switching the switching unit 66 to the energized state, the process of the regenerative power supply unit 14D returns to the process of step S30 (return).
On the other hand, when the power determination unit 70 determines that the regenerative power is less than the internal loss, the determination result is output to the switching control unit 68 and it is determined that the power consumption circuit control start flag is not established.

The switching control unit 68 that has received the determination result that the regenerative power is less than the internal loss generates an information signal for switching the switching unit 66 to the non-energized state (“power consumption circuit SW: OFF” shown in FIG. 15). . And this information signal is output to the switching part 66 (step S34).
After the switching control unit 68 outputs an information signal for switching the switching unit 66 to the non-energized state, the process of the regenerative power supply unit 14D returns to the process of step S30 (return).

(3) In the regenerative power control apparatus for a vehicle according to the present embodiment, the regenerative DC current threshold rIdc_siki is set to a value of 0 A or more. However, the present invention is not limited to this, and the regenerative DC current threshold rIdc_siki is 0 A. It may be set to a value exceeding. However, in this case, since the switching unit is energized before the regenerative power is generated, the operating point of the generator current and the DC voltage becomes equal to or less than the induced voltage of the motor. For this reason, based on the reason shown below, the voltage command value control part 14F controls the power generation command value to a generator, and controls a generator field current.

Hereinafter, the control of the power generation command value to the generator when the regenerative DC current threshold rIdc_siki is set to a value exceeding 0 A will be described with reference to FIGS. 16 and 17.
FIG. 16 is a diagram showing the movement of the generator current and the operating point in a state where the switching unit 66 is energized with the regenerative DC current threshold rIdc_siki exceeding 0A. Note that the horizontal axis, the vertical axis, and the plurality of straight lines A shown in FIG. 16 indicate the same elements as those shown in FIG.

As shown in FIG. 16, when the switching unit 66 is energized when the DC voltage Vdc is low and the position of the operating point is larger than 0 A by the regenerative DC current threshold rIdc_siki (LowP2 shown in FIG. 16), The operating point moves and the generator current increases. In addition, the DC voltage Vdc decreases. Then, the reduced DC voltage Vdc converges at the convergence operating point on the resistance value (LowR2 shown in FIG. 16).
In this state, since the reduced DC voltage Vdc is less than the induced voltage of the motor 8, the control of the motor 8 serving as the generator fails.

  On the other hand, the voltage command value controller 14F controls the voltage command value to the generator 4 according to the regenerative DC current threshold rIdc_siki. Specifically, for example, based on the characteristic diagram of the generator 4 as shown in FIG. 17, PI control is performed on the deviation between the current command value Idc * and the actual generated current value, and the actual generated current value is The generator field current of the generator 4 is controlled so as to follow the current command value Idc *. Also, PI control is performed on the deviation between the generated voltage command value Vdc * and the actual generated voltage value to correct the amplitude of the three-phase sine wave command. FIG. 17 is a characteristic diagram of the generator 4. Also, curves B1 to B4 shown in FIG. 17 are operating point trajectories when the field voltage PWM duty ratio is fixed and the load of the generator 4 is gradually changed in the self-excited region of the generator 4. Yes, curves B1 to B4 show the difference in duty ratio.

Accordingly, the switching unit 66 is energized at a point where the DC voltage Vdc is higher than the point lowP2 where the DC voltage Vdc is low (HiP2 shown in FIG. 16).
When the switching unit 66 is energized at the point HiP2 where the DC voltage Vdc is higher than lowP2, the operating point moves, the generator current increases, and the DC voltage Vdc decreases. The reduced DC voltage Vdc converges at a convergence operating point (HiR2 shown in FIG. 16) where the DC voltage Vdc is higher than LowR2 and the generator current is large.
In this state, since the reduced DC voltage Vdc is equal to or higher than the induced voltage of the motor 8, it is possible to prevent the control of the motor 8 serving as the generator from failing.

(4) Moreover, in the regenerative power control apparatus for a vehicle according to the present embodiment, the switching control unit energizes the switching unit according to the determination of whether or not the regenerative power by the power determination unit is equal to or greater than the internal loss. Or switch to a non-energized state. However, switching of the switching unit by the switching control unit is not limited to this. For example, the switching unit is switched to an energized state or a non-energized state according to a comparison between regenerative power and a preset power threshold. May be. However, as in the vehicle regenerative power control apparatus of the present embodiment, switching the switching unit to the energized state or the non-energized state according to the determination of whether or not the regenerative power is greater than or equal to the internal loss may be regenerative. It is preferable because power can be consumed efficiently.

(5) Further, in the regenerative power control device for a vehicle according to the present embodiment, when the regenerative power is generated and the switching unit is switched to the energized state, the power generation command value is controlled according to the generator current generated by the generator. Although the power generation command value control means is provided, it is not limited to this. In other words, the power generation command value control means may not be provided. However, like the vehicle regenerative power control device of this embodiment, the configuration including the power generation command value control means can stably supply the power generated by the generator to the inverter. Therefore, it is preferable.

(6) Further, the regenerative power control device for a vehicle according to the present embodiment includes a power generation amount control unit that controls the power generation amount of the generator when the regenerative power is generated and the switching unit is switched to the energized state. However, the present invention is not limited to this. In other words, the power generation amount control unit may not be provided. However, the configuration including the power generation amount control unit as in the vehicle regenerative power control device of the present embodiment does not require the power generated by the generator to be supplied to the inverter. It is preferable because the amount can be suppressed.

It is a schematic device block diagram of a vehicle provided with a regenerative power control device of the present invention. It is a figure which shows the structure of a power electronics part. 3 is a block diagram showing details of a 4WD controller 14. FIG. It is a block diagram which shows the detail of regenerative electric power supply part 14D. It is a flowchart which shows operation | movement of regenerative electric power supply part 14D. It is a block diagram which shows the detail of the motor control part 14E. It is a figure which shows an example of a motor field power generation command value characteristic map at the time of regenerative electric power generation. It is a flowchart which shows operation | movement of 14 C of regenerative electric power generation | occurrence | production determination parts, the regenerative electric power supply part 14D, and the motor control part 14E. It is a figure which shows the motion of the operating point of the generator current Igen and the DC voltage Vdc in the state which made the switching part 66 into the energized state. It is a time chart which shows the behavior of the motor 8 and the power electronics part at the time of driving | running | working of the vehicle provided with the regenerative electric power control apparatus of this invention. It is a figure which shows the operation | movement of the operating point of a generator current and DC voltage Vdc interlock | cooperating with a part of time chart of FIG. 10 provided with the regenerative electric power control apparatus of this invention. It is a time chart which shows the behavior of the motor 8 and the power electronics part at the time of driving | running | working of the vehicle by the regenerative electric power control apparatus of a prior art example. It is a figure which shows the motion of the operating point of the generator current and DC voltage Vdc interlock | cooperated with a part of time chart of FIG. FIG. 5 is a block diagram illustrating details of the switching control unit 68 when the switching control unit 68 performs duty control of the switching unit 66 in a state where the switching unit 66 is switched to an energized state. It is a flowchart which shows operation | movement of regenerative electric power supply part 14D in case the switching control part 68 performs duty control of the switching part 66 in the state which switched the switching part 66 to the energized state. It is a figure which shows the movement of a generator current and an operating point in the state which made the switching part 66 into the energized state in the state which the regenerative DC current threshold value rIdc_siki exceeds 0A. FIG. 6 is a characteristic diagram of the generator 4.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine 2 Main drive wheel 4 Generator 6 Inverter 8 Motor 10 Slave drive wheel 12 Engine controller 14 4WD controller 14B Generator supply electric power calculation part 14F Voltage command value control part 14G Power generation current command calculation part 16 Front wheel speed sensor 32 Rear wheel speed Sensor 34 Power consumption circuit 38 Generator side field circuit 40 Generator current sensor 42 DC current sensor 44 DC voltage sensor 46 Capacitor 54 Generator side field coil 56 Motor side field circuit 60 Motor side field coil 62 Motor field Current sensor 64 Power consumption unit 66 Switching unit 68 Switching control unit 70 Power determination unit

Claims (6)

A main drive source that drives the main drive wheel, a generator that generates power using the driving force from the main drive source as a motive power source, electric power generated by the generator is supplied, and the supplied electric power is converted into AC power Provided in a vehicle having an inverter to be converted, and a motor that is supplied with AC power converted by the inverter and drives the driven wheels,
A regenerative power control device for a vehicle comprising regenerative power consumption means for consuming regenerative power generated by the motor on the motor side of the generator,
Power calculation means for calculating the required power to be generated by the generator when driving the driven wheel, and power generation for controlling the power generation command value to the generator so that the power generated by the generator becomes the required power Command value control means,
The regenerative power consumption means includes a power consumption circuit connected in parallel and electrically between the generator and the inverter, and a DC voltage and a DC current on the DC side of the inverter when the regenerative power is generated. A regenerative power supply unit that supplies the regenerative power to the power consuming circuit according to at least one of the following:
The power consumption circuit connects a power consumption unit that consumes the regenerative power that is energized, a DC side of the inverter and the power consumption unit in an energized state, and a DC side of the inverter and the power in a non-energized state A switching unit that cuts off the connection with the consumption unit,
The regenerative power supply unit includes a switching control unit that switches the switching unit to the energized state or the non-energized state according to at least one of the DC voltage and the DC current,
When the regenerative power is generated and the switching control unit switches the switching unit to the energized state, the power generation command value control unit generates power generated by the generator as power calculated by the power calculation unit. As described above, the regenerative power control apparatus for a vehicle controls the power generation command value. The regenerative power supply unit includes a power determination unit that determines whether or not the regenerative power is greater than or equal to an internal loss composed of losses of the inverter and the motor when the regenerative power is generated,
The switching control unit switches the switching unit to the energized state when the power determination unit determines that the regenerative power is greater than or equal to the internal loss, and determines that the regenerative power is less than the internal loss. The regenerative power control device for a vehicle according to claim 1, wherein the switching unit is switched to the non-energized state. When the regenerative power is generated and the switching unit is switched to the energized state, voltage command value control means for controlling a voltage command value to the generator so that the DC voltage exceeds the induced voltage of the motor,
The voltage command value control means reduces the DC voltage after setting the switching unit to the energized state when the switching control unit switches the switching unit to the energized state and does not perform duty control of the switching unit. The voltage command value is controlled so that the DC voltage exceeds the induced voltage of the motor according to the amount and the increase amount of the DC voltage before the energized state,
When the switching control unit performs duty control of the switching unit in a state in which the switching unit is switched to the energized state, the DC voltage is set to the motor according to the DC voltage after the switching unit is set to the energized state. The regenerative power control device for a vehicle according to claim 1, wherein the voltage command value is controlled to exceed an induced voltage of the vehicle.   The power generation command value control means controls the power generation command value according to a generator current generated by the generator when the regenerative power is generated and the switching unit is switched to the energized state. The regenerative power control device for a vehicle according to any one of claims 1 to 3.   When the regenerative power is generated and the switching unit is switched to the energized state, the power generated by the generator can be consumed by an internal loss composed of the power consumption unit, the inverter, and the motor loss. The regenerative power control device for a vehicle according to any one of claims 1 to 4, further comprising: a power generation amount control unit that controls a power generation amount of the generator so as not to exceed. An inverter supplied with power generated by a generator that generates power using a driving force from a main driving source that drives the main driving wheel converts the supplied power into AC power, and the converted AC power is A regenerative power control method for a vehicle that consumes regenerative power generated by a motor that is supplied and drives a driven wheel, on the motor side of the generator,
A power consuming unit that consumes the regenerative power that is energized;
Connection between the DC side of the inverter and the power consuming unit or connection between the DC side of the inverter and the power consuming unit according to at least one of a DC voltage and a DC current on the DC side of the inverter when the regenerative power is generated Shut off
When the regenerative power is generated and the DC side of the inverter is connected to the power consumption unit, the power generation command value to the generator is set so that the power generated by the generator becomes the power calculated by the power calculation means. A regenerative electric power control method for a vehicle, comprising:

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