JP2009220665A - Vehicular driving controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent excessive reduction of output torque of a motor even when performing processing for regenerative power by making actual generation power follow target generation power. <P>SOLUTION: A vehicular driving force controller has: a map retrieval part 301 for calculating target power for driving the motor 4; a power consumption calculation part 307 for acquiring actual power in the motor 4; a second subtractor 303 for calculating a deviation between the target driving power and the actual power; and a power compensation PI control part 308 and a first upper/lower limit limiter part 305 calculating a q axis current instruction value Iq<SP>*</SP>for driving the motor 4 such that the deviation becomes zero, and restricting a lower limit side of the q axis current instruction value Iq<SP>*</SP>based on a motor torque instruction value. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle drive control device that drives drive wheels with a motor.

If the motor rotation direction and the command torque direction of the motor are reversed when starting on a slope, the regenerative power of Processing is required.
Patent Document 1 relates to a regenerative control device mounted on a vehicle, by changing a power command value with respect to a deviation between target generated power and actual generated power, thereby changing the output torque of the motor, A technique relating to processing of regenerative power that eliminates the deviation is disclosed.
JP 2000-92871 A

By the way, in the technique described in Patent Document 1, when the actual generated power becomes smaller than the target generated power, the actual generated power follows the target generated power by reducing the output torque (rollback torque) of the motor. Become. However, if the output torque (rollback torque) of the motor is lowered more than necessary, problems such as the inability to obtain the necessary driving force occur.
An object of the present invention is to prevent the output torque of a motor from being reduced more than necessary even when processing regenerative power by causing actual generated power to follow target generated power.

  In order to solve the above problems, the present invention calculates target power for driving an AC motor, obtains actual power in the AC motor, calculates a deviation between the target power and actual power, and calculates the same. The current command value for driving the AC motor is calculated so that the deviation becomes zero, and the lower limit side of the current command value is limited based on the motor torque command value of the AC motor.

  According to the present invention, by limiting the lower limit side of the current command value based on the motor torque command value of the AC motor, the output torque of the AC motor does not decrease more than necessary.

The best mode for carrying out the present invention (hereinafter referred to as an embodiment) will be described in detail with reference to the drawings.
FIG. 1 is a schematic configuration diagram when the present invention is applied to a four-wheel drive vehicle.
As shown in FIG. 1, in the vehicle of this embodiment, left and right front wheels 1L and 1R are main drive wheels driven by an engine 2 which is a heat engine (internal combustion engine), and left and right rear wheels 3L and 3R are This is a driven wheel that can be driven by the motor 4.

  For example, a main throttle valve and a sub-throttle valve are interposed in the intake pipe line of the engine 2. The throttle opening of the main throttle valve is adjusted and controlled according to the amount of depression of the accelerator pedal. The sub-throttle valve uses a step motor or the like as an actuator, and the opening degree is adjusted and controlled by a rotation angle corresponding to the number of steps. Therefore, by adjusting the throttle opening of the sub-throttle valve to be equal to or less than the opening of the main throttle valve, the engine output torque can be reduced independently of the driver's operation of the accelerator pedal. That is, the adjustment of the opening degree of the sub-throttle valve is the driving force control that suppresses the acceleration slip of the front wheels 1L, 1R by the engine 2.

The output torque Te of the engine 2 is transmitted to the left and right front wheels 1L, 1R through the transmission and the reference gear 5. Further, a part of the output torque Te of the engine 2 is transmitted to the generator 7 via the endless belt 6, so that the generator 7 has a rotation speed Ng obtained by multiplying the rotation speed Ne of the engine 2 by the pulley ratio. Rotate.
The generator 7 becomes a load on the engine 2 in accordance with the field current Ifg adjusted by the 4WD controller 8, and generates power in accordance with the load torque. The magnitude of the power generated by the generator 7 is determined by the magnitudes of the rotational speed Ng and the field current Ifg. The rotational speed Ng of the generator 7 can be calculated from the rotational speed Ne of the engine 2 based on the pulley ratio.

FIG. 2 is a diagram showing the structure of the field current drive circuit of the generator 7.
As shown in FIG. 2A, this circuit applies a configuration in which a constant voltage power source such as a 14V battery 7a of a vehicle and an output voltage of the generator itself are selected as a field current power source. Is connected to the field coil 7b to switch the transistor 7c. In this case, when the generator output is lower than the battery voltage Vb, the battery voltage Vb becomes a power source for the field coil 7b in a separate excitation region, the generator output increases, and the output voltage Vg is equal to or higher than the battery voltage Vb. Then, the output voltage Vg of the generator is selected as a self-excited region and becomes a power source for the field coil 7b. That is, since the field current value can be increased by the power supply voltage of the generator, the generator output can be significantly increased.

In the field current drive circuit, only the 14V battery 7a of the vehicle (only the separate excitation region) may be applied as the field current power source as shown in FIG. 2 (b).
The electric power generated by the generator 7 can be supplied to the motor 4 via the junction box 10 and the inverter 9. The drive shaft of the motor 4 can be connected to the rear wheels 3L and 3R via the speed reducer 11 and the clutch 12. In addition, the motor 4 of this embodiment is an AC motor. Moreover, the code | symbol 13 in a figure shows a difference gear.

In the junction box 10, a relay for connecting and disconnecting the inverter 9 and the generator 7 is provided. In a state where this relay is connected, DC power supplied from the generator 7 via a rectifier (not shown) is converted into three-phase AC in the inverter 9 to drive the motor 4.
The junction box 10 is provided with a generator voltage sensor that detects a generated voltage and a generator current sensor that detects a generated current that is an input current of the inverter 9. These detection signals are sent to the 4WD controller 8. Is output. Further, a resolver is connected to the drive shaft of the motor 4 and outputs a magnetic pole position signal θ of the motor 4.

The clutch 12 is, for example, a wet multi-plate clutch, and performs fastening and releasing according to a command from the 4WD controller 8. In this embodiment, the clutch as the fastening means is a wet multi-plate clutch. However, for example, a powder clutch or a pump-type clutch may be used.
Each wheel 1L, 1R, 3L, 3R is provided with a wheel speed sensor 27FL, 27FR, 27RL, 27RR. Each wheel speed sensor 27FL, 27FR, 27RL, 27RR outputs a pulse signal corresponding to the rotation speed of the corresponding wheel 1L, 1R, 3L, 3R to the 4WD controller 8 as a wheel speed detection value.

  The 4WD controller 8 includes an arithmetic processing unit such as a microcomputer, for example, and includes wheel speed signals detected by the wheel speed sensors 27FL to 27RR, output signals of voltage sensors and current sensors in the junction box 10, and motors. The output signal of the resolver connected to 4 and the accelerator opening corresponding to the amount of depression of an accelerator pedal (not shown) are input.

As shown in FIG. 3, the 4WD controller 8 includes a target motor torque calculation unit 8A, a generator supply power calculation unit 8B as a required motor power calculation unit, a generated current command calculation unit 8C, and a generator control as a generator control unit. A motor control unit 8E as a load fixing means, a TCS control unit 8F, and a clutch control unit 8G.
The target motor torque calculation unit 8A is configured to calculate the required driving force of the rear wheels 3L and 3R as the driven wheels, for example, the wheel speed difference between the front and rear wheels calculated based on the wheel speed signal of the four wheels, and the accelerator pedal opening signal. From this, the motor torque command value Tt is calculated.

The generator supply power calculation unit 8B calculates the generator supply power Pg based on the following equation based on the torque command value Tt and the motor rotation speed Nm.
Pg = Tt × Nm / Иm (1)
Here, Иm is the inverter efficiency. That is, the generator supply power Pg has a value that is higher by the inverter efficiency Иm than the power Pm (= Tt × Nm) required for the motor, which is obtained by the product of the torque command value Tt and the motor rotation speed Nm.
The generated current command calculation unit 8C is based on the generator supply power Pg calculated by the generator supply power calculation unit 8B and the generated voltage command value Vdc ^* calculated by a motor control unit 8E described later, based on the following formula: Based on the above, the generated current command value Idc ^* is calculated.
Idc ^* = Pg / Vdc ^* (2)

FIG. 4 is a block diagram showing details of the generator control unit 8D that performs power generation control of the generator 7.
The generator control unit 8D includes a P control unit 101, an I control unit 102, an FF control unit 103, a control amount addition unit 104, and a field control unit 105, and determines a field voltage PWM duty ratio C1. Then, the field current Ifg of the generator 7 is PWM controlled.
The P control unit 101 performs P control based on the deviation between the generated current command value Idc ^* calculated by the equation (2) and the actual generated current value Idc. First, the deviation between the generated current command value Idc ^* and the actual generated current value Idc is multiplied by a predetermined gain. Then, in order to make the gain sensitivity constant with respect to fluctuations in the rotational speed of the generator, this value is multiplied by the reciprocal of the generator rotational speed Ng, and this is used as a control amount Vp in P control, which will be described later. To 104.

The I control unit 102 performs I control based on the deviation between the generated current command value Idc ^* and the actual generated current value Idc calculated by the equation (2). That is, the deviation between the generated current command value Idc ^* and the actual generated current value Idc is integrated. Here, the integral value has an upper limit value and a lower limit value. Then, like the P control, this integral value is multiplied by the reciprocal of the generator rotational speed Ng, and this is output to the control amount adding unit 104 described later as the control amount Vi in the I control.

As shown in FIG. 5, the FF control unit 103 refers to a pre-stored generator characteristic map for each rotation speed, and generates power by feedforward based on the generated voltage command value Vdc ^* and the generated current command value Idc ^*. The PWM duty ratio D1 of the machine field voltage is obtained. In FIG. 5, curves a1 to a4 are locus of operating points when the field voltage PWM duty ratio D1 is fixed in the self-excited region of the generator 7 and the load of the generator 7 is gradually changed. Curves a1 to a4 show the difference in duty ratio D1.

Then, based on the PWM duty ratio D1 and the generated voltage command value Vdc ^* , the control amount Vff in the FF control is calculated based on the following equation and output to the control amount adding unit 104.
Vff = D1 × Vdc ^* (3)
In the present embodiment, the case where the control amount Vff is calculated based on the PWM duty ratio D1 and the generated voltage command value Vdc ^* has been described. However, the present invention is not limited to this, and the field of the generator 7 is not limited thereto. The control amount Vff may be calculated based on the current If and the field coil resistance Rf.

In this case, first, the necessary power generation voltage V ₀ and the necessary power generation current I ₀ required for the generator ₇ are calculated from the motor rotation speed Nm and the torque command value Tt with reference to a map stored in advance, and based on these. As shown in FIG. 6, the necessary field current If ₀ is calculated by referring to the field current characteristic map of the generator 7 for each rotation speed stored in advance. Then, the control amount Vff may be calculated by Vff = If ₀ × Rf based on the necessary field current If ₀ calculated in this way.

The control amount adding unit 104 adds the control amount Vp, the control amount Vi, and the control amount Vff, and outputs this to the field control unit 105 as a voltage Vf applied to the field coil.
The field control unit 105 determines whether or not the actual power generation voltage value Vdc is equal to or lower than the battery voltage Vb as the field current power source of the generator 7, and the actual power generation voltage value Vdc is equal to or lower than the battery voltage Vb (Vdc ≦ Vb). In some cases, the duty ratio C1 of the field voltage PWM is calculated based on the following equation (4).
C1 = Vf / Vb (4)
On the other hand, when actual power generation voltage value Vdc is larger than battery voltage Vb (Vdc> Vb), field voltage PWM duty ratio C1 is calculated based on the following equation (5).
C1 = Vf / Vdc (5)
Then, the field current Ifg of the generator 7 is controlled according to the duty ratio C1 calculated in this way.

That is, in this generator control unit 8D, the generator operating point for realizing the generator supply power Pg determined from the torque command value Tt is designated by feedforward, and the deviation between the generated current command value Idc ^* and the actual generated current value Idc is specified. Is fed back by PI compensation to cause the actual generated current value Idc to follow the generated current command value Idc ^* . Thereby, the field current Ifg of the generator 7 is controlled so as to supply the inverter 9 with the electric power according to the request of the motor 4.
Here, PI compensation is applied as a control method used for feedback control. However, the present invention is not limited to this, and any control method that stabilizes the system may be used.

FIG. 7 is a block diagram showing details of the motor control unit 8E that controls the motor 4 by the inverter 9. As shown in FIG.
The motor control unit 8E includes an Id / Iq command value calculation unit 201, a Vd / Vq command value calculation unit 202, a Vdc ^* command value calculation unit 203, a 2-phase / 3-phase conversion unit 204, and a PWM control unit 205. And a field current command value calculation unit 206 and a field magnetic flux calculation unit 207. The torque command value Tt calculated by the target motor torque calculation unit 8A is input and the actual motor torque T is converted into the torque command value Tt. The three-phase power element of the inverter 9 is subjected to switching control so that
In the Id, Iq command value calculation unit 201, based on the torque command value Tt and the motor rotation speed Nm, a d-axis (magnetic flux component) current and a q-axis (torque) for outputting torque that matches the torque command value Tt Component) Command values Id ^* and Iq ^* with current are calculated and output to the Vd and Vq command value calculation unit 202.

FIG. 8 shows a configuration used in the process when rollback occurs in the Id, Iq command value calculation unit 201.
As shown in FIG. 8, the Id and Iq command value calculation unit 201 includes a map search unit 301, first and second subtracters 302 and 303, a q-axis current compensation PI control unit 304, and first and second upper and lower limiters. Units 305 and 306, a power consumption calculation unit 307, a power compensation PI control unit 308, and an Id ^* upper limit calculation unit 309.
The map search unit 301 receives the torque command value Tt and the motor rotation speed Nm, and based on the input torque command value Tt and the motor rotation speed Nm, the q-axis current command value Iq ^* and the target power consumption The value (target generated power value) W ^* is calculated. The q-axis current command value Iq ^* calculated here is input to the first subtracter 302 and the first lower limiter unit 305, and the target power consumption value W ^* is input to the second subtractor 303.

The power consumption calculator 307 receives the actual power generation voltage value Vdc and the actual power generation current value Idc, and based on the input actual power generation voltage value Vdc and the actual power generation current value Idc, Generated power value) W (= Vdc × Idc) is calculated. The actual power consumption value W calculated here is input to the second subtractor 303.
The actual power consumption value W (= Id × Vd + Iq × Vq) can also be calculated based on the d-axis voltage value Vd, the d-axis current value Id, the q-axis voltage value Vq, and the q-axis current value Iq.

The second subtractor 303 outputs a value obtained by subtracting the actual power consumption value W from the input target power consumption value W ^* , that is, a power consumption value deviation (W ^* −W) to the power compensation PI control unit 308.
The power compensation PI control unit 308 determines the q-axis current command value Iq ^* by the PI compensator with respect to the deviation (W ^* −W) of the input power consumption value. For example, if the deviation (W ^* −W) of the power consumption value is a positive value, the q-axis current command value Iq ^* is reduced and the deviation (W ^* −W) of the power consumption value is a negative value due to insufficient power. For example, the q-axis current command value Iq ^* is increased due to excessive power. The q-axis current command value Iq ^* calculated here is input to the first upper / lower limiter unit 305.

The first upper and lower limit limiter unit 305, based on the q-axis current command value inputted from the map search unit 301 Iq ^*, to limit the power compensation PI control unit 308 by the calculated q-axis current command value Iq ^*. Specifically, the q-axis current command value calculated by the power compensation PI control unit 308 with a value (Iq ^* + α) obtained by adding a predetermined value to the q-axis current command value Iq ^* input from the map search unit 301 as an upper limit. Limit Iq ^* . Thus, the first upper / lower limiter unit 305 sets the power compensation PI with a value (Iq ^* + α) obtained by adding a predetermined value to the q-axis current command value Iq ^* input from the map search unit 301 as a limit (maximum value). The q-axis current command value Iq ^* ′ calculated by the control unit 308 is calculated. The lower limit value is zero. The q-axis current command value Iq ^* ′ calculated here is input to the first subtracter 302 and the Id ^* upper limit calculation unit 309.

The Id ^* upper limit calculation unit 309 calculates the upper limit value Idmax of the d-axis current command value Id ^* based on the current limit value Ia determined from the hardware configuration such as the motor 4 and the inverter 9. Specifically, the following equation (6) is assumed to be established among the current limit value Ia, the q-axis current command value Iq ^*, and the d-axis current command value Id ^* :
√ (Iq ^* ′ ² + Id ^{* 2} ) ≦ Ia (6)
The upper limit value Idmax of the d-axis current command value Id ^* is calculated by the following equation (7). Here, the current limit value Ia is a current value determined by, for example, an element of the inverter 9 or the like.
Idmax ≦ √ (Ia ² −Iq ^{* 2} ) (7)
The upper limit value Idmax calculated here is input to the second upper / lower limiter unit 306.

On the other hand, the first subtractor 302 subtracts the q-axis current command value Iq ^* ′ input from the first upper / lower limiter unit 305 from the q-axis current command value Iq ^* input from the map search unit 301, That is, the deviation (Iq ^* −Iq ^* ′) of the q-axis current command value Iq ^* is output to the q-axis current compensation PI control unit 304.
The q-axis current compensation PI control unit 304 determines the d-axis current command value Id ^* by the PI compensator with respect to the input deviation (Iq ^* −Iq ^* ′) of the q-axis current command value Iq ^* . The d-axis current command value Id ^* determined here is input to the second upper / lower limiter unit 306.

The second upper / lower limiter unit 306 limits the d-axis current command value Id ^* input from the q-axis current compensation PI control unit 304 based on the upper limit value Idmax input from the Id ^* upper limit calculation unit 309. Accordingly, the second upper / lower limit limiter 306 outputs the d-axis current command value Id ^* input from the q-axis current compensation PI control unit 304 with the upper limit value Idmax as a limit (maximum value). The lower limit value is zero.

As described above, in the Id, Iq command value calculation unit 201, based on the torque command value Tt and the motor rotational speed Nm, the d-axis current command value Id ^* for outputting torque that matches the torque command value Tt and The q-axis current command value Iq ^* (specifically, Iq ^* ′) is calculated.
In the Vd, Vq command value calculation unit 202, the current command values Id ^* , Iq ^* (specifically Iq ^* ′) input from the Id, Iq command value calculation unit 201, the motor rotation speed Nm, and a field to be described later Based on the motor parameters (inductance Ld, Lq, field magnetic flux Φ) input from the magnetic flux calculator 207, the d-axis voltage command value Vd for changing the d-axis current value Id to the d-axis current command value Id ^{*. *} And a q-axis voltage command value Vq ^* for making the q-axis current value Iq the q-axis current command value Iq ^* are calculated.

The Vdc ^* command value calculation unit 203 calculates the generated voltage command value Vdc ^* based on the voltage command values Vd ^* and Vq ^* calculated by the Vd, Vq command value calculation unit 202, and the generator shown in FIG. Output to the control unit 8D.
Vdc ^* = 2√2 / √3 · √ (Vd ^{* 2} + Vq ^{* 2} ) (8)
Further, in the two-phase / three-phase conversion unit 204, the dq-axis voltage command values Vd ^* and Vq ^* calculated by the Vd and Vq command value calculation unit 202 are converted to the U phase of the three-phase coordinate system which is a three-phase sine wave command value. The voltage command value Vu ^* , the V-phase voltage command value Vv ^* , and the W-phase voltage command value Vw ^* are converted and output to the PWM control unit 205.

The PWM control unit 205 calculates the PWM command by comparing with the triangular wave based on the three-phase sine wave command value input from the two-phase / three-phase conversion unit 204, and outputs a switching signal to be output to the inverter 9. Generate. The inverter 9 generates a PWM wave voltage corresponding to the switching signal and applies it to the motor 4, thereby driving the motor 4.
In the case of the triangular wave comparison, in the present embodiment, the sine wave amplitude is normalized by Vu ^* / Vdc ^* using the generated voltage command value Vdc ^* , which is a DC voltage command value, for example, in the U phase. A U-phase switching signal is output by comparing the command value with the triangular wave. Thereby, the impedance of the inverter viewed from the generator is fixed for each combination of the torque command value Tt and the motor rotation speed Nm. That is, this corresponds to fixing the pulse width of the PWM wave voltage for each torque command value Tt and motor rotation speed Nm.

The field current command value calculation unit 206 calculates a field current command value If ^* based on the motor rotation speed Nm and outputs it to the field magnetic flux calculation unit 207. The field magnetic flux calculation unit 207 The magnetic flux is calculated and output to the Vd, Vq command value calculation unit 202 described above.
Therefore, in this motor control unit 8E, the operation of the inverter is fixed to the required motor output with a switching pattern performed when the required voltage is satisfied.

In FIG. 7, the PWM control unit 205 corresponds to the PWM control means.
Further, the TCS control unit 8F in FIG. 3 uses a known method based on an engine generation drive torque demand signal Tet from an unillustrated engine torque controller (ECM), the rotational speeds V _FR and V _{FL of} the left and right front wheels, and the vehicle speed V. Thus, the front wheel traction control control is performed by returning the engine generated drive torque demand signal Te to the ECM.
The clutch control unit 8G controls the state of the clutch 12, and controls the clutch 12 to the connected state while determining that the vehicle is in the four-wheel drive state.

(Operation, action and effect)
Operation, action and effect are as follows.
Now, it is assumed that the vehicle is determined to be in the four-wheel drive state, and the motor torque command value Tt is calculated based on the wheel speed and the accelerator pedal opening. In this case, the generator control unit 8D performs PI control on the deviation between the generated current command value Idc ^* calculated based on the motor torque command value Tt and the generated current value Idc, and the generated current value Idc is generated. Field current Ifg of generator 7 is controlled so as to follow current command value Idc ^* .
Then, the motor control unit 8E calculates a three-phase sine wave command for switching control of the three-phase power element of the inverter 9 based on the torque command value Tt and the motor rotation speed Nm. Based on this, a PWM command is calculated and output to the inverter 9.

  At this time, the motor control unit 8E calculates the generated voltage value Vdc from the U-phase voltage command value Vu, and outputs this to the generator control unit 8D. Further, the motor control unit 8E obtains a U-phase current value Iu based on the dq-axis current command values Idr and Iqr, calculates a generated current value Idc from the U-phase current value Iu, and supplies this to the generator control unit 8D. Output. Then, the generator control unit 8D executes power generation control using the generated voltage value Vdc and the generated current value Idc calculated by the motor control unit 8E.

On the other hand, when rollback occurs, the following processing is performed.
The map search unit 301 calculates the target power consumption value W ^* based on the torque command value Tt and the motor rotation speed Nm, and the power consumption calculation unit 307 calculates the actual power generation voltage value Vdc and the actual power generation current value Idc. Based on this, the actual power consumption value W (= Vdc × Idc) is calculated. Then, in the second subtracter 303, a value obtained by subtracting the actual power consumption value W from the target power consumption value W ^* , that is, a deviation (W ^* −W) of the power consumption value is calculated and input to the power compensation PI control unit 308. Is done.

In the power compensation PI control unit 308, the q-axis current command value Iq ^* is determined by the PI compensator with respect to the deviation (W ^* −W) of the power consumption value. In the first upper / lower limiter unit 305, the map The q-axis current command value Iq ^* calculated by the power compensation PI control unit 308 is limited by the q-axis current command value Iq ^* input from the search unit 301. That is, the first upper and lower limit limiter unit 305 is calculated by the power compensation PI control unit 308 with a value (Iq ^* + α) obtained by adding a predetermined value to the q-axis current command value Iq ^* input from the map search unit 301 as a limit. The q-axis current command value Iq ^* ′ is calculated.

On the other hand, in the first subtracter 302, the first upper and lower limits are calculated from the q-axis current command value Iq ^* input from the map search unit 301, that is, the q-axis current command value Iq ^* calculated based on the torque command value Tt. A value obtained by subtracting the q-axis current command value Iq ^* ′ input from the limiter unit 305, that is, a deviation (Iq ^* −Iq ^* ′) of the q-axis current command value Iq ^* is calculated, and the q-axis current compensation PI control unit 304 is calculated. Then, with respect to the deviation (Iq ^* −Iq ^* ′) of the q-axis current command value Iq ^* , the d-axis current command value Id ^* is determined by the PI compensator.

Then, in the second upper / lower limit limiter 306, the q-axis current compensation PI controller 304 uses the upper limit value Idmax of the d-axis current command value Id ^* calculated based on the current limit value Ia by the Id ^* upper limit calculator 309. The input d-axis current command value Id ^* is limited.
Thus, the motor torque is changed (decreased ⁾ by controlling the q-axis current command value Iq ^* so that the deviation (W ^* −W) between the target power consumption value W ^* and the actual power consumption value W becomes zero. ) And the generation of regenerative power can be suppressed.

At this time, the q-axis current command value is controlled while controlling the q-axis current command value Iq ^* so that the deviation (W ^* −W) between the target power consumption value W ^* and the actual power consumption value W becomes zero. Iq ^* and the deviation between the q-axis current command value Iq ^* calculated on the basis of the torque command value Tt ^{(Iq *} -Iq * ') is determined d-axis current command value Id ^* to be zero. That is, the final d-axis current command value Id ^* is determined based on the q-axis current command value Iq ^* calculated based on the torque command value Tt. As a result, even when the motor torque is reduced, the reduction can be prevented from being performed more than necessary. That is, by determining the d-axis current command value Id ^* as described above (by increasing the d-axis current command value Id ^* ), the deviation (W from the target power consumption value W ^* to the actual power consumption value W) ^Since the operation amount of the q-axis current command value Iq ^* operated so that ^* −W) becomes 0 can be returned to 0, a change in motor torque can be suppressed. As a result, it is possible to prevent the motor torque from being reduced more than necessary.

Thereby, when the actual power consumption value W becomes smaller than the target power consumption value W ^* , the actual power consumption value W is made to follow the target power consumption value W ^* by reducing the torque command value Tt. However, even in this case, it is possible to prevent the torque command value Tt from being lowered more than necessary by limiting the q-axis current command value Iq ^* .
Further, when calculating the d-axis current command value Id ^* based on the q-axis current command value Iq ^* , for example, the d-axis current command value Id based on the current limit value Ia determined by the element of the inverter 9 or the like. ^* Is calculated (formula (7)). That is, the d-axis current command value Id ^* is set so that the square root of the square sum of the q-axis current command value Iq ^* and the d-axis current command value Id ^* is equal to or less than the current limit value Ia that is a predetermined threshold value ^. Is limited (limited by the upper limit value Idmax).

In this way, while the determined d-axis current command value Id ^* prevents the elements of the inverter 9 from being destroyed (with further restrictions), the motor torque decreases more than necessary. Can be prevented. Here, we have decided to limit side of the d-axis current command value Id ^* from time to time in the q-axis current command value Iq ^*, thereby, spreads the range of use of the d-axis current command value Id ^*. For this reason, there are many opportunities for the deviation (Iq ^* −Iq ^* ′) between the q-axis current command value Iq ^* and the q-axis current command value Iq ^* ′ to be zero. As a result, the change in torque can be suppressed to the minimum, and the motor torque can be prevented from decreasing more than necessary.

In the description of the embodiment, the map search unit 301 realizes a target power calculation unit that calculates a target power for driving the AC motor, and the power consumption calculation unit 307 includes an actual power in the AC motor. Real power acquisition means for acquiring power is realized, and the second subtractor 303 calculates a deviation between the target power calculated by the target power calculation means and the actual power acquired by the real power acquisition means. The calculation means is realized, and the first and second subtractors 302 and 303, the q-axis current compensation PI control unit 304, and the power compensation PI control unit 308 are configured such that the deviation calculated by the power deviation calculation unit becomes zero. Current command value calculating means for calculating a current command value for driving the AC motor and limiting a lower limit side of the current command value based on a motor torque command value of the AC motor It is realized.
In the description of the embodiment, the first upper / lower limiter unit 305 controls the upper limit side of the q-axis current value for driving the AC motor that controls the deviation calculated by the power deviation calculation unit to be zero. The current command value calculation means for limiting the value based on the motor torque command value is realized.

It is a schematic structure figure showing an embodiment of the present invention. It is a figure which shows the structure of a generator. It is a block diagram which shows the detail of 4WD controller. It is a block diagram which shows the detail of a generator control part. It is a generator characteristic map for every rotation speed. It is a field current characteristic map for every number of rotations. It is a block diagram which shows the detail of a motor control part. It is a block diagram which shows the detail of Id, Iq command value calculating part.

Explanation of symbols

1L, 1R front wheel, 2 engine, 3L, 3R rear wheel, 3a drive shaft, 4 motor, 4a drive shaft, 6 belt, 7 generator, 8 4WD controller, 8A target motor torque calculator, 8B generator supply power calculator , 8C power generation current command calculation unit, 8D generator control unit, 8E motor control unit, 8F TCS control unit, 8G clutch control unit, 8H load fixing determination unit, 8I motor control unit, 9 inverter, 10 junction box, 11 reducer , 12 clutch, 27FL, 27FR, 27RL, 27RR wheel speed sensor, 201 Id, Iq command value calculation unit, 301 map search unit, 302, 303 first and second subtractors, 304 q-axis current compensation PI control unit, 305 , 306 First and second upper / lower limiter unit, 307 Power consumption calculation unit, 308 Power compensation PI control unit, 309 Id ^* Upper limit calculator

Claims (4)

A vehicle drive comprising: a main drive source that drives main drive wheels; a generator driven by the main drive source; and an AC motor that supplies power from the generator through an inverter to drive the driven wheels In the control device,
Target power calculation means for calculating target power for driving the AC motor;
Real power acquisition means for acquiring real power in the AC motor;
Power deviation calculating means for calculating a deviation between the target power calculated by the target power calculating means and the actual power acquired by the actual power acquiring means;
The current command value for driving the AC motor is calculated so that the deviation calculated by the power deviation calculating means becomes zero, and the lower limit side of the current command value is based on the motor torque command value of the AC motor. Current command value calculation means for limiting to,
A vehicle drive control device comprising:   The target power calculation means calculates a target power based on the rotational speed of the AC motor and a motor torque command value, and the current command value calculation means sets the deviation calculated by the power deviation calculation means to zero. Thus, while controlling the q-axis current value for driving the AC motor, the deviation between the q-axis current value and the q-axis current value determined based on the motor torque command value becomes zero. The d-axis current value orthogonal to the q-axis current is controlled, and the AC motor is driven based on the controlled q-axis current value and d-axis current value. The vehicle drive control device described.   The upper limit side of the d-axis current value is limited so that the square root of the square sum of the q-axis current value and the d-axis current value is equal to or less than a predetermined threshold value. Vehicle drive control apparatus.   The current command value calculation means limits the upper limit side of the q-axis current value for driving the AC motor that controls the deviation calculated by the power deviation calculation means to be zero based on the motor torque command value. The vehicle drive control device according to claim 2, wherein the vehicle drive control device is a vehicle drive control device.

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