JP2009040111A - Generator control device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a generator control device of a vehicle for improving the stability of a vehicle behavior. <P>SOLUTION: In the generator control device of a vehicle installed in a vehicle having an engine 1; a main driving wheel 2; a generator 4; an invertor 6; an AC motor 8; and a driven wheel 10. When it is determined that the variable Δid of d axial currents to be supplied from the AC side of the invertor 6 to the AC motor 8 exceeds a value permitted by a voltage command value Vdc, a first voltage command value V1dc* is calculated so that the AC side voltage of the invertor 6 can be set to permit the variable Δid of the d axial currents, and a generator control signal including the calculated first voltage command value V1dc* is output to the generator 4. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention drives a generator with a main drive source such as an engine that serves as a drive source for a main drive shaft, and drives an AC motor that serves as a drive source for a driven drive shaft via an inverter by the output of the generator. The present invention relates to a vehicular generator control device.

Conventionally, the power generation target value required for the generator is calculated based on the motor torque command value, and feedback control is performed so that the output voltage value of the generator becomes this power generation target value. As a generator control device for a vehicle that drives an AC motor according to the output of the machine, for example, there is one described in Patent Document 1.
Japanese Patent Laying-Open No. 2006-187090 (FIG. 1)

A vehicle equipped with a conventional generator control device, including a vehicle equipped with a vehicle generator control device as described in Patent Document 1, uses a field winding motor as an AC motor. There are many.
In a vehicle using a field winding type motor as an AC motor, the field current that generates magnetic flux forms the main parameter directly related to the vehicle behavior. The controllability is closely related. The field current is easily affected by changes in the stator current (especially the d-axis current), and the response of the field current is changed by changing the magnitude of the power supply voltage (field voltage) of the field winding. Change.

  By the way, for example, in a vehicle in which the main driving wheel is driven by the engine and the driven wheel is driven by an AC motor as described in Patent Document 1, a system voltage that varies depending on the operating state of the AC motor; Of the battery voltages maintained at a constant voltage value (for example, 14V), the higher voltage is often used as the field voltage. That is, the field voltage changes according to the fluctuation of the system voltage.

In such a vehicle, when it is necessary to suddenly change the motor torque or the motor speed, the AC motor drive state changes, and particularly when the d-axis current (stator current) changes, As a result, the field current changes. When the field current changes, the generator field voltage also changes in accordance with this change.
However, when the system voltage is small, etc., when the generated voltage command value for outputting the necessary power to be output by the generator is small and the amount of change in the field current exceeds the field voltage of the generator, that is, If the amount of change in the field current exceeds the value allowed by the generator field voltage, the actual generator field voltage and the generated voltage command value may be significantly different.

If the actual generator field voltage and the generator voltage command value deviate greatly, the responsiveness of the actual generator field voltage to the generator voltage command value will be degraded. It becomes difficult to make the magnetic voltage follow the generated voltage command value in a short time.
Therefore, it takes time for the field voltage of the actual generator to follow the generated voltage command value, and the controllability of the field current will fluctuate, the controllability of the field current will not be stable, There is a risk that the stability of the vehicle behavior is lowered.
The present invention has been made paying attention to the above-mentioned problems, and improves the stability of vehicle behavior by improving the responsiveness of the actual generator field voltage to the generated voltage command value. It is an object of the present invention to provide a generator control device for a vehicle that can be used.

In order to solve the above-mentioned problems, the present invention is directed to an AC motor in which electric power of a generator that generates power using a driving force from a main driving source that drives a main driving wheel as a power source drives a driven wheel via an inverter. Provided in the vehicle to be supplied,
The generated voltage and generated current of the generator are controlled to the generated voltage command value and generated current command value for outputting the necessary power to be output by the generator according to the driving state of the AC motor, and the generator A generator control device for a vehicle that controls electric power,
If it is determined that the amount of change in the d-axis current supplied from the AC side of the inverter to the AC motor exceeds the value permitted by the DC side voltage of the inverter, the DC side voltage of the inverter is A generator control device for a vehicle is provided that controls the generated voltage command value based on a change amount of the d-axis current so that a change amount of the d-axis current is allowed. .

According to the present invention, when it is determined that the amount of change in the d-axis current supplied from the AC side of the inverter to the AC motor exceeds the value permitted by the DC side voltage of the inverter, the voltage on the DC side of the inverter The generated voltage command value is controlled based on the amount of change in the d-axis current so that becomes a value that allows the amount of change in the d-axis current.
For this reason, it becomes possible to improve the responsiveness of the field voltage of the actual generator with respect to the generated voltage command value, and to improve the stability of the field current control.
As a result, the stability of the motor torque generated from the AC motor can be improved, and the stability of the vehicle behavior can be improved.

Embodiments of the present invention will be described below with reference to the drawings.
(First embodiment)
(Constitution)
FIG. 1 is a schematic configuration diagram of a vehicle including a vehicle generator control device according to the present embodiment.
As shown in FIG. 1, the generator control device for a vehicle according to this embodiment includes an engine 1, a main drive wheel 2, a generator 4, an inverter 6, an AC motor 8, and a slave drive wheel 10. It is equipped with the vehicle which has.
The engine 1 is an internal combustion engine and constitutes a main drive source that drives the main drive wheels 2.
Further, the engine 1 communicates with the outside air by an intake pipe (not shown) formed by an intake manifold, for example, and a main throttle valve and a sub throttle valve (both not shown) are connected to the intake pipe. Is intervening.

  The main throttle valve is connected to an accelerator pedal, which is an accelerator opening degree indicating device, and is configured to be adjusted and controlled by opening and closing according to the amount of depression of the accelerator pedal. The accelerator pedal is provided with an accelerator sensor for detecting the accelerator opening, and the accelerator sensor has a function of transmitting an information signal including the detected accelerator opening to the engine controller 12.

The engine controller 12 is connected to the accelerator sensor and the 4WD controller 14, and electrically adjusts and controls the main throttle valve based on the accelerator opening detected by the accelerator sensor and the signal transmitted from the 4WD controller 14. It has a function of adjusting the main throttle opening and controlling the driving state of the engine 1.
The sub-throttle valve includes 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 detected value of the sub-throttle opening detected by the throttle sensor. It has become.

  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 degree of the sub-throttle valve is the driving force control for suppressing the acceleration slip of the main drive wheel 2 by the engine 1.

The engine 1 also includes an engine speed detection sensor (not shown) that detects the speed Ne of the engine 1. The engine speed detection sensor is connected to the 4WD controller 14 described later, and has a function of transmitting an information signal including the detected engine speed Ne to the 4WD controller 14 when the engine speed Ne is detected. is doing.
The main drive wheel 2 is composed of left and right front wheels 2L, 2R.
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 is connected to the 4WD controller 14, and detects the rotational speed of the corresponding left and right front wheels 2L, 2R, respectively, and outputs an information signal including a pulse signal corresponding to the detected rotational speed. 4WD controller 14 has a function to transmit.

A transmission and a differential gear 18 as a transmission are interposed between the engine 1 and the left and right front wheels 2L and 2R. When the engine 1 is driven, the output torque Te of the engine 1 causes the transmission and the differential gear 18 to Via the left and right front wheels 2L, 2R.
The generator 4 has a rotating shaft connected to the rotating shaft of the engine 1 via an endless belt 20. The rotating shaft of the generator 4 is a rotational speed obtained by multiplying the rotational speed Ne of the engine 1 by the pulley ratio by transmitting a part of the output torque Te of the engine 1 to the generator 4 via the endless belt 20. It is configured to rotate and generate electric power. That is, the generator 4 is driven by the power of the engine 1 to generate electric power.

Further, the generator 4 has a generator rotation speed detection means (not shown) for detecting the rotation speed of the rotation shaft, and the rotation speed of the rotation shaft detected by the generator rotation speed detection means is The rotation speed Ng of 4 is output to the 4WD controller 14.
Here, the electric power generated by the generator 4 is determined from the rotational speed Ng of the generator 4 and the magnitude of the field current Ifg. As will be described later, the magnitude of the field current Ifg is controlled by a 4WD controller 14 connected to the generator 4, and the generator 4 becomes a load on the engine 1 in accordance with the controlled field current Ifg. Then, power generation according to the load torque is performed. That is, the power generated by the generator 4 is controlled by the 4WD controller 14.

The electric power generated by the generator 4 can be supplied to the AC motor 8 via the electric wire 22 and the inverter 6. A junction box 24 is provided in the middle of the electric wire 22.
In the junction box 24, a relay for connecting and disconnecting the inverter 6 and the generator 4 is provided. In the state where this relay is connected, the electric power supplied from the generator 4 is converted into a three-phase current in the inverter 6 to drive the AC motor 8. That is, the inverter 6 has a function of driving the AC motor 8 using the power generated by the generator 4 as a drive source. The inverter 6 is connected to the 4WD controller 14.

The AC motor 8 is formed by a field winding type motor, and constitutes a slave drive source for driving the slave drive wheels 10. The AC motor 8 is connected to the 4WD controller 14.
The AC motor 8 includes a rotor (not shown) having field windings and a stator (FIG. 3) wound with three-phase (U-phase, V-phase, W-phase) windings for generating a rotating magnetic field. (Not shown), and the rotational motion is generated by the interaction between the magnetic field generated by passing a current through the field winding of the rotor and the rotating magnetic field generated by the three-phase winding wound around the stator. It is configured to do.

Here, when the rotor is rotated by an external force, such as when the vehicle is in regenerative braking, an electromotive force is generated at both ends of the three-phase winding due to the interaction between the two magnetic fields described above. Is configured to generate electricity.
The drive shaft of the AC motor 8 can be connected to the driven wheel 10 via the speed reducer 26, the clutch 28 and the differential 30. Therefore, the AC motor 8 is configured to drive the driven wheel 10 in a state where the drive shaft of the AC motor 8 is connected to the driven wheel 10.

The driven wheel 10 is composed of left and right rear wheels 10L, 10R.
Rear wheel speed sensors 32RL and 32RR are provided on the left and right rear wheels 10L and 10R, respectively. Each of the rear wheel speed sensors 32RL and 32RR is connected to the 4WD controller 14 and detects the rotational speed of the corresponding left and right rear wheels 10L and 10R, and includes an information signal including a pulse signal corresponding to the detected rotational speed. Is transmitted to the 4WD controller 14.

  The clutch 28 is formed by, for example, a wet multi-plate clutch, and is interposed in a torque transmission path from the AC motor 8 to the left and right rear wheels 10L, 10R. In the present embodiment, the case where the clutch 28 is a wet multi-plate clutch will be described. However, the present invention is not limited to this. For example, the clutch 28 may be a hydraulic clutch, an electromagnetic clutch, a powder clutch, A pump-type clutch may be used.

  Further, the clutch 28 enters a connected state or a released state in accordance with a clutch control command output from the 4WD controller 14. When the clutch 28 is in the connected state, the drive shaft of the AC motor 8 is connected to the left and right rear wheels 10L and 10R, the vehicle is in a four-wheel drive state, and the left and right front wheels 2L and 2R and the left and right rear wheels 10L and 10R become drive wheels. . When the clutch 28 is released, the connection between the drive shaft of the AC motor 8 and the left and right rear wheels 10L, 10R is released, the vehicle is in a two-wheel drive state, and only the left and right front wheels 2L, 2R are drive wheels.

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, an AC motor 8, and a 4WD controller 14.
The generator 4 is connected to the inverter 6 via a rectifier 34 and has a generator-side field circuit 36.
A generator current sensor 38 and a voltage sensor 40 are disposed between the rectifier 34 and the inverter 6. Both the generator current sensor 38 and the voltage sensor 40 are provided in the junction box 24.

The generator current sensor 38 has a function of detecting the current supplied from the generator 4 to the input side of the inverter 6, that is, the generator current, and the detection of the generator current detected by the generator current sensor 38. The signal is output to the 4WD controller 14.
The voltage sensor 40 has a function of detecting a DC side voltage of the inverter 6, and a DC side voltage detection signal detected by the voltage sensor 40 is output to the 4WD controller 14.
An AC motor 8 is connected to the output circuit of the inverter 6, and a small capacitor 42 is installed in parallel in the input circuit of the inverter 6 to form a capacitor input type circuit.

A V-phase current sensor 44 and a W-phase current sensor 46 are disposed between the output circuit of the inverter 6 and the AC motor 8.
The V-phase current sensor 44 has a function of detecting a V-phase current output from the AC side of the inverter 6 to the AC motor 8, and the V-phase current detection signal detected by the V-phase current sensor 44 is 4WD. It is output to the controller 14.
The W-phase current sensor 46 has a function of detecting the W-phase current output from the AC side of the inverter 6 to the AC motor 8, and the W-phase current detection signal detected by the W-phase current sensor 46 is 4WD. It is output to the controller 14.

The generator-side field circuit 36 includes a constant voltage power supply 48 and a generator-side field coil 50, and the magnitude of the generator field current is determined according to the generator control signal output from the 4WD controller 14. It has a function to control. In the present embodiment, a 14V battery mounted on the vehicle is used as the constant voltage power supply 48.
The AC motor 8 has a motor-side field circuit 52, and a resolver 54 is connected to its drive shaft.
The resolver 54 has a function of detecting the rotational angle position θ of the rotor of the AC motor 8, and the rotational angle position θ of the rotor detected by the resolver 54 is output to the 4WD controller 14 as a rotor rotational angle position signal. The

Here, the detection signal of the V-phase current detected by the V-phase current sensor 44, the detection signal of the W-phase current detected by the W-phase current sensor 46, and the rotor rotation angle position signal detected by the resolver 54 include the inverter 6 The d-axis (magnetic flux component) current and the q-axis (torque component) current supplied from the AC side to the AC motor 8 are included. Then, the d-axis current and the q-axis current are detected independently and output to the 4WD controller 14.
The motor-side field circuit 52 includes a motor-side field coil 56 and has a function of controlling the motor field current flowing in the motor-side field circuit 52 using the voltage generated by the generator 4 as a power source. Yes. Further, the motor-side field circuit 52 shares a constant voltage power supply 48 included in the generator-side field circuit 36 as a constant voltage power supply.

The motor side field coil 56 is provided with a motor field current sensor 58, and the motor field current sensor 58 has a function of detecting a motor field current flowing through the motor side field circuit 52. Yes. A motor field current detection signal detected by the motor field current sensor 58 is output to the 4WD controller 14.
The 4WD controller 14 includes an arithmetic processing unit such as a microcomputer, for example, and has a function of outputting a generator field voltage signal to the generator-side field circuit 36 and a motor to the motor-side field circuit 52. It has a function of outputting a field voltage signal and a function of outputting a three-phase switching pulse signal to the inverter 6.

FIG. 3 is a configuration diagram of the generator-side field circuit 36.
As shown in FIG. 3, the generator-side field circuit 36 has a configuration in which the constant voltage power supply 48 or the output voltage (system voltage) of the generator 4 itself is selected as the field current power supply. The transistor 60 is switched by connecting the anode side of the field current power source to the generator-side field coil 50. In this case, in a state where the system voltage Vg is lower than the battery voltage Vb, the battery voltage Vb becomes a power source for the generator-side field coil 50 in a separate excitation region, and the output of the generator 4 increases to increase the system voltage Vg. Becomes the self-excited region, the output voltage Vg of the generator 4 is selected and becomes the power source for the generator-side field coil 50. That is, by using the larger one of the system voltage Vg and the battery voltage Vb as the power supply voltage, the field power supply voltage is prevented from becoming 0 [V]. In addition, since the field current value can be increased according to the system voltage, the generator output can be significantly increased.

4 and 5 are configuration diagrams of the motor-side field circuit 52. FIG.
FIG. 5 is a schematic diagram showing the motor-side field circuit 52 shown in FIG. 4 in a simplified manner.
As shown in FIGS. 4 and 5, the motor-side field circuit 52 has a configuration in which a constant voltage power supply 48 or a system voltage is selected as a field current power supply in the same manner as the generator-side field circuit 36. Similarly to the motor-side field circuit 52, the larger one of the system voltage and the battery voltage is used as the power supply voltage to prevent the field power supply voltage from becoming 0 [V]. Yes.
In addition, the configuration of the motor-side field circuit 52 includes a known H-bridge circuit so that a reverse voltage is applied to the motor-side field circuit 52 by the motor control signal output from the 4WD controller 14. The configuration is compatible.

FIG. 6 is a block diagram showing details of the 4WD controller 14.
As shown in FIG. 6, the 4WD controller 14 includes a target motor torque calculator 14A, a generator supply power calculator 14B, a generated current command calculator 14C, a motor controller 14D, a TCS controller 14E, a clutch controller 14F, An allowable voltage determination unit 14G, a generator control unit 14H, and a motor current command value calculation unit 14I are provided.
The target motor torque calculator 14A is based on the wheel speed difference between the main drive wheel 2 and the slave drive wheel 10 calculated based on the wheel speed signals of the main drive wheel 2 and the slave drive wheel 10, and the accelerator pedal opening. A motor torque command value Tr * is calculated.

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.
Pg = Tr * × Nm / Иm (1)
Here, Иm is the inverter efficiency. That is, the generator supply power Pg is larger 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. It becomes. The motor rotational speed Nm is calculated based on the rotational angle position θ of the rotor detected by the resolver 54.

The generated current command calculation unit 14C generates the generated current command value idc 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 generator control unit 14H. * Is calculated by the following equation (2).
Idc * = Pg / Vdc * (2)
Then, the generated current command calculation unit 14C outputs the generated current command value idc * calculated by the above-described equation (2) to the generator 4 as a generator control signal.

FIG. 7 is a block diagram showing details of the motor control unit 14D.
As shown in FIG. 7, the motor control unit 14D includes a motor field current command value calculation unit 100, a motor field current feedback control unit 102, a PI control unit 104, and a duty control unit 106. .
The motor field current command value calculation unit 100 is based on the motor rotation speed Nm, the motor torque command value Tr * calculated by the target motor torque calculation unit 14A, and the motor field current command value characteristic map stored in advance. Then, the motor field current command value If * is calculated. Then, the calculated motor field current command value If * is output to the motor field current feedback control unit 102.

The motor field current feedback control unit 102 calculates a deviation ΔIf between the motor field current command value If * and the field current If by feedback control, and outputs the calculated deviation ΔIf to the PI control unit 104. .
In this embodiment, the field current If is the motor field current detected by the motor field current sensor 58. However, the present invention is not limited to this, and the field current If is a map prepared in advance. Or may be estimated from an arithmetic expression or the like.

When the deviation ΔIf between the motor field current command value If * and the field current If is input, the PI control unit 104 performs PI control on the deviation ΔIf and then performs the deviation ΔIf subjected to PI control. Is output to the duty control unit 106.
When duty control unit 106 receives deviation ΔIf between motor field current command value If * subjected to PI control and field current If, deviation ΔIf subjected to PI control using field voltage Vf is input. Duty control is performed on the motor to generate a motor control signal. The generated motor control signal is output to the motor-side field circuit 52.

Here, the field voltage Vf is a voltage input to the motor-side field circuit 52.
The TCS control unit 14E generates an engine for the ECM by a known method based on an engine generation drive torque demand signal Tet from an engine torque controller (ECM) (not shown), the rotational speeds Vfr and Vfl of the left and right front wheels, and the vehicle speed. Front wheel traction control control is performed by sending back the drive torque demand signal Te.

The clutch control unit 14F controls the state of the clutch 28, and controls the clutch 28 to be in a connected state while determining the four-wheel drive state.
Allowable voltage determination unit 14 </ b> G determines whether or not the amount of change in d-axis current exceeds a value permitted by the voltage on the DC side of inverter 6.
Here, the amount of change in the d-axis current is detected based on the deviation between the d-axis current and the d-axis current command value. Specifically, the d-axis current change amount Δid is detected by subtracting the d-axis current id from the d-axis current command value id ** to obtain a deviation between the two. The calculation of the d-axis current command value id ** will be described later.

Then, the detected change amount Δid of the d-axis current is compared with the voltage command value Vdc, and the change amount Δid of the d-axis current exceeds the voltage command value Vdc, that is, the change amount Δid of the d-axis current is the voltage command value. If it is determined that the value allowed by the value Vdc is exceeded, the d-axis current change amount detection unit 108 and the first voltage command value calculation unit 110 of the generator control unit 14H are activated.
On the other hand, when it is determined that the change amount Δid of the d-axis current is equal to or less than the voltage command value Vdc, that is, the change amount Δid of the d-axis current does not exceed the value permitted by the voltage command value Vdc, the four-wheel drive state Continue processing at.

FIG. 8 is a block diagram showing details of the generator control unit 14H.
As shown in FIG. 8, the generator control unit 14H includes a d-axis current change amount detection unit 108, a first voltage command value calculation unit 110, a second voltage command value calculation unit 112, and a select high unit 114. I have.
The d-axis current change amount detection unit 108 detects the change amount Δid of the d-axis current based on the deviation between the d-axis current id and the d-axis current command value id ** in the same procedure as the allowable voltage determination unit 14G. To do. Then, the detected change amount Δid of the d-axis current is output to the first voltage command value calculation unit 110.

  The first voltage command value calculation unit 110 applies the change amount Δid of the d-axis current detected by the d-axis current change amount detection unit 108 to the first allowable voltage command value characteristic map stored in advance. Then, the first voltage command value V1dc * is calculated such that the DC side voltage of the inverter 6 becomes a value that allows the change amount Δid of the d-axis current, and the calculated first voltage command value V1dc * is selected. Output to the high part 114.

On the other hand, the second voltage command value calculation unit 112 applies the motor torque command value Tr *, the motor rotation speed Nm, and the rotation speed Ng of the generator 4 to the second allowable voltage command value characteristic map stored in advance. Then, the second voltage command value V2dc * is calculated, and the calculated second voltage command value V2dc * is output to the select high unit 114.
The select high unit 114 selects the first voltage command value V1dc * output from the first voltage command value calculation unit 110 and the second voltage command value V2dc * output from the second voltage command value calculation unit 112. The selected high value is output to the generated current command calculation unit 14C as the generated voltage command value Vdc *. That is, the first voltage command value V1dc * and the second voltage command value V2dc * are compared, and the larger one of the first voltage command value V1dc * and the second voltage command value V2dc * is determined as the generated voltage. The command value Vdc * is output to the generated current command calculation unit 14C.

Here, the calculation of the first voltage command value V1dc * in the first voltage command value calculation unit 110 will be described with reference to FIGS.
FIG. 9 is a diagram showing a d-axis equivalent circuit of AC motor 8, and FIG. 10 is a diagram showing a relationship among d-axis current id, field current If, and field voltage Vf.
As shown in FIGS. 9 and 10, when the d-axis current id is changed by a change amount Δid, the magnetic flux Φ generated in the mutual inductance Md between the d-axis current and the field current If is changed. Therefore, an induced electromotive force is generated according to the law of electromagnetic induction, and the d-axis current id is induced in a direction that prevents the change of the magnetic flux Φ.

At this time, the field current If is controlled so as to cancel the change according to the change amount Δid of the d-axis current, but when the field voltage Vf is not sufficient for the induced electromotive force, That is, when the change amount Δid of the d-axis current exceeds the change amount ΔIf of the field current If, the change amount Δid is not allowed as the change amount ΔIf. Therefore, the difference between the field voltage Vf and the voltage command value Vdc becomes large, and there arises a problem that it takes time until the field voltage Vf follows the voltage command value Vdc.
With respect to this problem, in the present embodiment, when the field voltage Vf with respect to the change amount Δid of the d-axis current is not sufficient, the generator is calculated by calculating the first voltage command value V1dc * in the first voltage command value calculation unit 110. The above-described problem is solved by increasing the power generation amount of 4 to ensure a sufficient field voltage Vf.

11 and 12 are block diagrams showing details of the motor current command value calculation unit 14I.
As shown in FIG. 11, the motor current command value calculation unit 14I includes an allowable d-axis change amount calculation unit 116, a d-axis current target value calculation unit 118, a q-axis current target value calculation unit 120, and a d-axis current. The command value limiting unit 122 and the q-axis current command value calculating unit 124 are configured.
The allowable d-axis variation calculation unit 116 compares the field voltage Vdc and the voltage (14V) of the constant voltage power supply 48 to obtain a larger voltage, and based on the obtained voltage (field power supply voltage), An allowable change amount Δida of the d-axis current that is allowable with the field voltage Vdc is calculated. At the same time, the sign of the allowable change amount Δida of the d-axis current is determined based on the following equation (3).
Δida = id * −id (3)
That is, if id *> id, the sign of Δida is “+”, and if id * <id, the sign of Δida is “−”.

The d-axis current target value calculation unit 118 applies the motor torque command value Tr * and the motor rotational speed Nm to the d-axis current target value characteristic map (id * map) stored in advance, and d-axis current target value id. * Is calculated. Then, the calculated d-axis current target value id * is output to the d-axis current command value limiter 122 and the q-axis current command value calculator 124.
The q-axis current target value calculation unit 120 applies the motor torque command value Tr * and the motor rotation speed Nm to a q-axis current target value characteristic map (iq * map) stored in advance, so that the q-axis current target value iq * Is calculated. Then, the calculated q-axis current target value iq * is output to the q-axis current command value calculation unit 124.
The d-axis current command value limiting unit 122 adds the d-axis current allowable change amount Δida calculated by the allowable d-axis change amount calculating unit 116 and the d-axis current id, and the d-axis current is added to the added value. Limit processing is performed based on the current target value id *, and the d-axis current command value id ** is calculated.

That is, when the d-axis current command value limiting unit 122 determines that the change amount Δid of the d-axis current exceeds the value allowed by the DC side voltage of the inverter 6 by the allowable voltage determination unit 14G, Based on the field power supply voltage, processing for limiting the d-axis current command value id ** is performed so that the d-axis current id does not exceed the change amount Δid of the d-axis current.
The calculated d-axis current command value id ** is added to the three-phase switching pulse signal and output to the inverter 6. In this case, limit processing is performed according to the sign of the allowable change amount Δida of the d-axis current.

FIG. 12 is a block diagram showing details of the q-axis current command value calculation unit 124.
As shown in FIG. 12, the q-axis current command value calculation unit 124 includes a follow-up rate calculation unit 126, a q-axis current feedback control unit 128, an integration unit 130, and an addition unit 132.
The follow-up rate calculation unit 126 calculates a follow-up rate ta for the q-axis current iq from the d-axis current target value id * and the d-axis current command value id **, and outputs the follow-up rate ta to the integration unit 130. Specifically, the following rate ta is calculated from the following equation (4).
ta = id * / id ** (4)

That is, when the d-axis current target value id * and the d-axis current command value id ** are equal, the follow-up rate ta is “1”.
The follow-up rate calculating unit 126 is configured to calculate the follow-up rate ta based on the d-axis current target value id *, the d-axis current command value id **, and a pre-stored follow-up rate characteristic map. Also good.
The q-axis current feedback control unit 128 feedback-controls the q-axis current target value iq * calculated by the q-axis current target value calculation unit 120 and the q-axis current command value iq ** calculated by the addition unit 132. Then, the difference Δiq between the q-axis current target value iq * and the q-axis current command value iq ** is calculated, and the calculated difference Δiq is output to the integrating unit 130.
The integration unit 130 integrates the tracking rate ta output from the tracking rate calculation unit 126 and the difference Δiq output from the q-axis current feedback control unit 128, and outputs the integrated value taΔiq to the addition unit 132.

The adding unit 132 adds the integrated value taΔiq output from the integrating unit 130 and the q-axis current target value iq * calculated by the q-axis current target value calculating unit 120, and uses this added value as the q-axis current command value. iq ** is output to the q-axis current feedback control unit 128 and added to the three-phase switching pulse signal to be output to the inverter 6.
That is, in the q-axis current command value calculation unit 124, the q-axis current command value is based on the d-axis current command value id ** so that the change amount of the q-axis current iq follows the change amount Δid of the d-axis current. A process of limiting iq ** is performed.

The generator supply power calculation unit 14B as described above constitutes a power calculation unit that calculates a power generation target value of necessary power that the generator 4 should generate according to the driving state of the AC motor 8. .
Further, the generated current command calculation unit 14C and the generator control unit 14H as described above convert the generated voltage and generated current of the generator 4 into the generated voltage command value and generated current command value for outputting the necessary power. Power control means for controlling and controlling the power of the generator 4 is configured.

Further, the V-phase current sensor 44, the W-phase current sensor 46, the resolver 54, and the d-axis current change detection unit 108 as described above change in the d-axis current supplied from the AC side of the inverter 6 to the AC motor 8. A d-axis current change amount detecting means for detecting the amount Δid is configured.
Further, the voltage sensor 40 as described above constitutes a DC side voltage detecting means for detecting a DC side voltage of the inverter 6.

Further, the allowable voltage determination unit 14G as described above determines whether or not the change amount Δid of the d-axis current exceeds the voltage command value Vdc, that is, a value permitted by the voltage on the DC side of the inverter 6. The allowable voltage determining means is configured.
Further, when the generator controller 14H determines that the change amount Δid of the d-axis current exceeds the value allowed by the voltage command value Vdc by the allowable voltage determiner 14G, the voltage command The generated voltage command value control means for controlling the generated voltage command value is configured such that the value Vdc is a value that allows the change amount Δid of the d-axis current.

Further, the d-axis current command value limiting unit 122 as described above is based on the voltage on the DC side of the inverter 6 so that the d-axis current id does not exceed the change amount Δid of the d-axis current. D-axis current command value limiting means for limiting the value id ** is configured.
Further, the q-axis current command value calculation unit 124 as described above is based on the d-axis current command value id ** so that the change amount of the q-axis current iq follows the change amount Δid of the d-axis current. q-axis current command value limiting means for limiting the q-axis current command value is configured.

(Operation)
Next, the operation of the vehicle generator control device will be described with reference to FIGS.
During traveling of the vehicle, for example, the torque transmitted from the engine 1 to the left and right front wheels 2L, 2R due to factors such as a small road surface μ or a large amount of depression of the accelerator pedal by the driver is a road surface reaction force limit torque. That is, when the left and right front wheels 2L, 2R, which are the main drive wheels 2, are accelerated and slipped, the clutch 28 is connected and the generator 4 generates power so as to output a motor torque corresponding to the acceleration slip amount. Thus, the vehicle shifts from the two-wheel drive state to the four-wheel drive state.

When the driving state of the AC motor 8 changes, such as when the motor torque changes suddenly or when the rotational speed of the AC motor 8 changes suddenly while the vehicle is running in a four-wheel drive state, the d-axis current id is changed to the d-axis current id. A change corresponding to the change amount Δid of the current occurs.
When a change corresponding to the change amount Δid of the d-axis current occurs in the d-axis current id, the allowable voltage determination unit 14G compares the change amount Δid of the d-axis current with the voltage command value Vdc, and the change amount Δid of the d-axis current is If it is determined that the allowable value of the voltage command value Vdc is exceeded, the d-axis current change amount detection unit 108 and the first voltage command value calculation unit 110 of the generator control unit 14H are activated.

Then, in the generator control unit 14H, the d-axis current change amount detection unit 108 detects the change amount Δid of the d-axis current based on the deviation between the d-axis current command value id ** and the d-axis current id. Further, the first voltage command value calculation unit 110 calculates the first voltage command value V1dc * such that the voltage on the DC side of the inverter 6 is a value that allows the change amount Δid of the d-axis current.
Next, the first voltage command value V1dc * calculated by the first voltage command value calculation unit 110 is calculated from the motor torque command value Tr *, the motor rotation speed Nm, and the rotation speed Ng of the generator 4. Compared with the two voltage command value V2dc *, the larger voltage command value of the two is output to the generated current command calculation unit 14C as the generated voltage command value Vdc *.

Hereinafter, when the first voltage command value V1dc * is larger than the second voltage command value V2dc *, that is, the first voltage command value V1dc * is generated as the generated voltage command value Vdc *, and the generated current command calculation unit 14C. The case of outputting to will be described.
On the other hand, in the motor current command value calculation unit 14I, the d-axis current target value id * is compared with the allowable change amount Δida of the d-axis current, which can be the larger of the field voltage Vdc and the voltage of the constant voltage power supply 48. The limit process is performed by calculating the d-axis current command value id **. The calculated d-axis current command value id ** is added to the three-phase switching pulse signal and output to the inverter 6.

The motor current command value calculation unit 14I is calculated by the follow-up rate ta, the difference Δiq between the q-axis current target value iq * and the q-axis current command value iq **, and the q-axis current target value calculation unit 120. Based on the q-axis current target value iq *, a q-axis current command value iq ** is calculated, and the calculated q-axis current command value iq ** is added to the three-phase switching pulse signal and output to the inverter 6. .
The inverter 6 to which the three-phase switching pulse signal is input is connected from the AC side of the inverter 6 based on the d-axis current command value id ** and the q-axis current command value iq ** added to the three-phase switching pulse signal. The d-axis current id and the q-axis current iq supplied to the motor 8 are controlled.

Therefore, even when it is determined that the change amount Δid of the d-axis current exceeds the value allowed by the voltage command value Vdc, the voltage on the DC side of the inverter 6 allows the change amount Δid of the d-axis current. The generated voltage command value Vdc * is controlled so as to be a value to be set.
For this reason, it becomes possible to improve the responsiveness of the actual field voltage of the generator 4 with respect to the generated voltage command value Vdc *, and it is possible to improve the stability of the field current control.

(Application example)
In the vehicle generator control device of this embodiment, the allowable change amount Δida of the allowable d-axis current calculated by the allowable d-axis change amount calculation unit 116 in the d-axis current command value limiting unit 122, and d The axis current id is added, and the added value is subjected to limit processing by the d-axis current target value id * to calculate the d-axis current command value id **. However, the present invention is not limited to this. That is, for example, the d-axis current command value limiter 122 is not formed, and the d-axis current command value is not subjected to limit processing on the value obtained by adding the allowable change amount Δida of the d-axis current and the d-axis current id. id ** may be calculated. However, as in the generator control device of the present embodiment, a limit process is performed with the d-axis current target value id * on the value obtained by adding the allowable change amount Δida of the d-axis current and the d-axis current id, and d The calculation of the shaft current command value id ** prevents an excessive load from being applied to the AC motor 8 and improves the stability of the field control until the amount of power generated by the generator 4 increases. This is preferable.

  In the vehicular generator control device of the present embodiment, the q-axis current command value calculation unit 124 determines the follow-up rate ta and the difference Δiq between the q-axis current target value iq * and the q-axis current command value iq **. The q-axis current command value iq ** is calculated based on the q-axis current target value iq * calculated by the q-axis current target value calculation unit 120. However, the present invention is not limited to this. That is, for example, the q-axis current command value iq ** may be calculated based only on the q-axis current target value iq * without forming the q-axis current command value calculation unit 124. However, like the generator control device of the present embodiment, calculating the q-axis current command value iq ** based on the follow-up rate ta, the difference Δiq, and the q-axis current target value iq * is d-axis. This is preferable because it is possible to prevent the balance between the current and the q-axis current from being lost.

  Further, in the vehicle generator control device of the present embodiment, the configuration of the motor-side field circuit 52 is configured such that a reverse voltage is applied to the motor-side field circuit 52 by the motor control signal output from the 4WD controller 14. However, the present invention is not limited to this. In other words, the configuration of the motor-side field circuit 52 may be a configuration that does not correspond when a reverse voltage is applied. However, as in the generator control device of the present embodiment, the configuration of the motor-side field circuit 52 is configured to be compatible with a case where a reverse voltage is applied to the motor-side field circuit 52. The motor controllability can be improved, and the stability of the motor torque generated from the AC motor can be improved, which is preferable.

  In the vehicle generator control device of this embodiment, the second voltage command value calculation unit 112 stores the motor torque command value Tr *, the motor rotation speed Nm, and the rotation speed Ng of the generator 4 in advance. The second voltage command value V2dc * is calculated by applying to the second allowable voltage command value characteristic map. However, the present invention is not limited to this. That is, the second voltage command value V2dc * may be calculated without using the rotational speed Ng of the generator 4. However, like the generator control device of the present embodiment, calculating the second voltage command value V2dc * using the rotation speed Ng of the generator 4 finely adjusts the second voltage command value V2dc *. Is preferable.

In the vehicle generator control device of the present embodiment, the engine 1 is used as the main drive source, but the AC motor 8 may be used as the main drive source.
In the vehicle generator control device of the present embodiment, a case will be described in which the present invention is applied to a four-wheel drive vehicle in which the left and right front wheels 2L and 2R are main drive wheels and the left and right rear wheels 10L and 10R are slave drive wheels. However, the present invention is not limited to this, and the present invention may be applied to a vehicle in which the left and right rear wheels 10L and 10R are main drive wheels and the left and right front wheels 2L and 2R are sub drive wheels.

  Further, in the vehicle generator control device of the present embodiment, the case where the present invention is applied to a four-wheel drive vehicle has been described, but the present invention is not limited to this, and includes two or more drive wheels in the front-rear direction, The present invention may be applied to a case where some main drive wheels are driven by an engine and the remaining slave drive wheels are driven by an AC motor. In addition, the present invention may be applied to an electric drive device that drives an electric motor for driving wheels by a generator that is rotationally driven by a rotational drive source such as an internal combustion engine.

(Effects of the first embodiment)
(1) In the vehicle generator control device of the present embodiment, when the change amount of the d-axis current supplied from the AC side of the inverter to the AC motor exceeds the value allowed by the DC side voltage of the inverter. When the determination is made, the generated voltage command value is controlled so that the voltage on the DC side of the inverter becomes a value that allows the change amount of the d-axis current.
For this reason, it becomes possible to improve the responsiveness of the field voltage of the actual generator with respect to the generated voltage command value, and to improve the stability of the field current control.
As a result, the stability of the motor torque generated from the AC motor can be improved, and the stability of the vehicle behavior can be improved.

(2) Further, in the vehicle generator control device of this embodiment, the d-axis current command value limiting unit is based on the voltage on the DC side of the inverter so that the d-axis current does not exceed the amount of change in the d-axis current. Thus, the d-axis current command value is limited.
As a result, the d-axis current command value is prevented from exceeding the d-axis current required for the AC motor, thereby preventing an excessive load from being applied to the AC motor.
In addition, in the control of a generator that is less responsive than an AC motor, it is possible to improve the stability of field control until the amount of power generated by the generator increases, and the motor torque generated from the AC motor It becomes possible to improve stability.

(3) Further, in the vehicle generator control device of the present embodiment, the d-axis current command value is calculated by the q-axis current command value calculation unit so that the change amount of the q-axis current follows the change amount of the d-axis current. Based on the q-axis current command value is limited.
As a result, it is possible to prevent the d-axis current and the q-axis current from being out of balance, preventing the induced voltage of the AC motor from increasing, and preventing the control of the AC motor from failing.

(4) Also, in the vehicle generator control device of the present embodiment, the configuration of the motor-side field circuit is configured so that a reverse voltage is applied to the motor-side field circuit by the motor control signal output from the 4WD controller. It is the structure which can respond also to.
As a result, in addition to the effects (1) and (2) described above, the controllability of the AC motor can be further improved, and the stability of the motor torque generated from the AC motor can be improved.
(5) Further, in the vehicle generator control device of the present embodiment, the change amount of the d-axis current is detected based on the deviation between the d-axis current and the d-axis current command value.
As a result, the amount of change in the d-axis current can be detected with a simple configuration such as a current sensor.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic apparatus block diagram of the vehicle provided with the generator control apparatus of the vehicle of embodiment of this invention. It is a figure which shows the structure of a power electronics part. 3 is a configuration diagram of a generator-side field circuit 36. FIG. 3 is a configuration diagram of a motor-side field circuit 52. FIG. FIG. 5 is a simplified configuration diagram of FIG. 4. 3 is a block diagram showing details of a 4WD controller 14. FIG. It is a block diagram which shows the detail of motor control part 14D. It is a block diagram which shows the detail of the generator control part 14H. 2 is a diagram showing a d-axis equivalent circuit of an AC motor 8. FIG. It is a figure which shows the relationship between the d-axis current id, the field current If, and the field voltage Vf. It is a block diagram which shows the detail of the motor current command value calculating part 14I. 4 is a block diagram showing details of a q-axis current command value calculation unit 124. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine 2 Main drive wheel 4 Generator 6 Inverter 8 AC motor 10 Sub drive wheel 12 Engine controller 14 4WD controller 16 Front wheel speed sensor 18 Differential gear 20 Endless belt 22 Electric wire 24 Junction box 26 Reduction gear 28 Clutch 30 Differential 32 Rear wheel speed Sensor 34 Rectifier 36 Generator side field circuit 38 Generator current sensor 40 Voltage sensor 42 Small capacitor 44 V phase current sensor 46 W phase current sensor 48 Constant voltage power supply 50 Generator side field coil 52 Motor side field circuit 54 Resolver 56 Motor side field coil 58 Motor field current sensor 60 Transistor 100 Motor field current command value calculation unit 102 Motor field current feedback control unit 104 PI control unit 106 Duty control unit 108 d-axis current change Quantity detection unit 110 First voltage command value calculation unit 112 Second voltage command value calculation unit 114 Select high unit 116 Allowable d-axis change amount calculation unit 118 d-axis current target value calculation unit 120 q-axis current target value calculation unit 122 d-axis Current command value limiting unit 124 q-axis current command value calculation unit 126 tracking rate calculation unit 128 q-axis current feedback control unit 130 integration unit 132 addition unit

Claims (5)

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 power source, and an AC motor that drives the driven wheel by supplying power from the generator via an inverter And provided in a vehicle having
Power calculating means for calculating the necessary power to be output by the generator according to the driving state of the AC motor;
A power control means for controlling the power of the generator by controlling the generated voltage and generated current of the generator to a generated voltage command value and a generated current command value for outputting the necessary power; A generator control device,
D-axis current change amount detecting means for detecting a change amount of a d-axis current supplied from the AC side of the inverter to the AC motor;
DC side voltage detection means for detecting the DC side voltage of the inverter;
An allowable voltage determining means for determining whether or not the amount of change in the d-axis current exceeds a value allowable for the DC side voltage of the inverter;
When the allowable voltage determination means determines that the amount of change in the d-axis current exceeds a value allowed for the DC side voltage of the inverter, the power control means determines that the DC side voltage of the inverter is Power generation of a vehicle, characterized by comprising power generation voltage command value control means for controlling the power generation voltage command value based on the amount of change in the d-axis current so as to be a value allowing the amount of change in the d-axis current. Machine control device.   If it is determined by the allowable voltage determination means that the amount of change in the d-axis current exceeds a value permitted by the DC side voltage of the inverter, the d-axis current exceeds the amount of change in the d-axis current. 2. The vehicle generator control device according to claim 1, further comprising d-axis current command value limiting means for limiting a d-axis current command value based on a voltage on a DC side of the inverter.   Q-axis current command value limiting means is provided for limiting the q-axis current command value based on the d-axis current command value so that the q-axis current change amount follows the d-axis current change amount. The generator control device for a vehicle according to claim 2.   The said generated voltage command value control means controls the said generated voltage command value so that the voltage of the direct current | flow side of the said inverter may become a reverse voltage, It described in any one of Claim 1 to 3 characterized by the above-mentioned. Vehicle generator control device.   5. The vehicle generator control device according to claim 1, wherein the change amount of the d-axis current is a deviation between the d-axis current and the d-axis current command value. 6. .

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