JP4747961B2 - Vehicle drive control device - Google Patents

Description

  The present invention relates to a vehicle drive control device that drives a generator with a heat engine (for example, an engine) that drives a main drive shaft and drives an AC motor with the output of the generator.

As a conventional vehicle drive control device, a driven wheel is driven by a DC motor driven by electric power of a generator, and a drive torque is controlled by controlling a field current of the DC motor. It is known (see, for example, Patent Document 1).
JP 2001-239852 A

  However, in the above conventional vehicle drive control device, since the motor torque is controlled by applying a DC motor, it is necessary to increase the armature current of the DC motor in order to increase the torque. Since the life of the brush of the DC motor is limited, there is a limit to the increase in the armature current, which makes it difficult to apply to a heavy vehicle or cannot improve the 4WD performance.

Further, although it is conceivable to use a DC motor capable of generating a large motor torque, there is a problem that it is too large when applied to a vehicle.
In order to avoid these, the configuration of an AC motor + inverter is applied instead of the DC motor, energy from the generator is supplied to the AC motor via the inverter, and the rotational speed control and torque control of the AC motor are performed. It is possible to use an inverter.
By the way, AC motor control methods include PWM control based on a pulse amplitude modulation method, rectangular wave control in which 180-degree energization is performed, inverter load fixing control in which only voltage phase control is performed, and the like.

In the PWM control, the actual three-phase AC current flowing through the AC motor is detected, and this is fed back to the PWM pulse to ensure the control accuracy of the motor torque. However, in the rectangular wave control or the inverter load fixing control, the voltage phase of the power supplied to the AC motor can be changed, but the operation cannot be performed up to the amplitude of the voltage applied to the AC motor. For this reason, there is a problem that it is difficult to ensure the control accuracy of the motor torque.
Accordingly, the present invention has been made paying attention to the unsolved problems of the above-described conventional example, and provides a vehicle drive control device capable of improving 4WD performance by a combination of a generator and an AC motor. The purpose is that.

In order to achieve the above object, a vehicle drive control apparatus according to the present invention includes a heat engine that drives main drive wheels, a generator that is driven by the heat engine, and electric power of the generator via an inverter. An AC motor that is supplied to drive the driven wheels, motor required power calculation means for calculating the motor required power required by the AC motor, and motor required power calculated by the motor required power calculation means are generated. And a motor control means for controlling the AC motor by applying a voltage having a fixed modulation rate for supplying a current corresponding to a predetermined current command value to the generator control means for controlling the generator. A current detection means for detecting an actual current value flowing through the AC motor, a q-axis component of the actual current value detected by the current detection means, and a q-axis component of the current command value. Based on deviation And the generated power correction means for correcting the control amount by the generator control means so that the q-axis component of the actual current value matches the q-axis component of the current command value, and the actual detection value detected by the current detection means. Voltage phase correction that corrects the voltage phase of the voltage applied to the AC motor so that the ratio of the d-axis component and the q-axis component of the current value matches the ratio of the d-axis component and the q-axis component of the current command value. And means .

According to the vehicle drive control device of the present invention, the control amount by the generator control means is corrected so that the q-axis component of the actual current value flowing through the AC motor matches the q-axis component of the current command value. Therefore, by controlling the power generation output of the generator, the q-axis component acting as the torque current of the AC motor can be matched with the q-axis component of the current command value, and the accuracy of torque control of the AC motor is improved. Can be achieved. Since the current control accuracy of the q-axis current of the AC motor can be improved by controlling the power generation output on the generator side, the AC motor is controlled only by phase control using an applied voltage with a fixed modulation factor. Even if it exists, the improvement of a torque precision can be aimed at. Further, the voltage phase correction means causes the voltage of the applied voltage to the AC motor so that the ratio of the d-axis component and the q-axis component of the actual current value matches the ratio of the d-axis component and the q-axis component of the current command value. Since the phase is corrected, the accuracy of the torque control of the AC motor can be further improved.

Hereinafter, embodiments of the present invention will be described 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 motors. 4 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 less than or equal to 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 and 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 magnitude 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 illustrating an example of a 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.

As shown in FIG. 2B, the field current drive circuit may apply only the vehicle 14V battery 7a (only the separate excitation region) as the field current power source.
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. The motor 4 of the present embodiment is a three-phase 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. Further, for example, a current sensor (current detection means) 15 for detecting U-phase, V-phase and W-phase currents is provided in the power supply line between the inverter 9 and the motor 4, and this detection signal is sent to the 4WD controller 8. Is output.

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 a wet multi-plate clutch, for example, 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, An output signal of a resolver connected to the motor 4 and an accelerator opening corresponding to an 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. 8D, a motor control unit 8E as a motor control 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, a torque command value Tt to be generated by the motor 4 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 the 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 the generator characteristic map for each rotation speed stored in advance, 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 ^* , a 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 necessary for the generator ₇ are calculated with reference to a map stored in advance from the motor rotation speed Nm and the torque command value Tt. 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 required 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 less than the battery voltage Vb as the field current power source of the generator 7. If Vdc ≦ Vb, the field control unit 105 determines the field based on the following equation (4). The duty ratio C1 of the magnetic voltage PWM is calculated.
C1 = Vf / Vb (4)
On the other hand, when 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 three-phase / two-phase conversion unit 203, a phase F / B control unit 204, and generated power correction means. Vdc ^* command value calculation unit 205, voltage phase command value calculation unit 206 as voltage phase correction means, sine wave command value calculation unit 207, PWM control unit 208, field current command value calculation unit 209, The three-phase power of the inverter 9 so that the actual motor torque T becomes the torque command value Tt when the torque command value Tt calculated by the target motor torque calculation unit 8A is input. Switching control of the element.

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, Vq command value calculation unit 202 and the phase F / B control unit 204.
In the Vd, Vq command value calculation unit 202, the d-axis and q-axis current command values Id ^* and Iq ^* input from the Id and Iq command value calculation unit 201, the motor rotation speed Nm, and field magnetic flux calculation described later. Based on the motor parameters (inductance Ld, Lq, field magnetic flux Φ) input from the unit 210, the d-axis current value Id is changed to the d-axis current command value Id ^* according to the following equations (6) and (7). the d-axis voltage command value Vd for ^*, the q-axis current value Iq to calculate the q-axis voltage command value to the q-axis current command value Iq ^* Vq ^*. In the equations (6) and (7), R is the resistance value of the field winding of the motor 4, and ω is the rotational speed of the motor 4.
Vd ^* = Id ^* · R−ω · Lq · Iq ^* (6)
Vq ^* = Iq ^* · R + ω · Ld · Id ^* + Φ · ω (7)

In the three-phase / two-phase converter 203, the U-phase current value Iu, the V-phase current value Iv, and the W-phase current value Iw, which are the three-phase AC current values detected by the current sensor, are the two-phase DC current values. The d-axis current value Id and the q-axis current value Iq are converted and output.
The phase F / B control unit 204 determines a correction value for the phase of the voltage applied to the motor 4. Specifically, first, the calculation shown in the following equation (8) is performed to calculate the three-phase current phase θidc that is the phase of the three-phase alternating current value. Further, based on the d-axis and q-axis current command values Id ^* and Iq ^* calculated by the Id, Iq command value calculation unit 201, the calculation shown in the following equation (9) is performed, and a three-phase AC current value command is obtained. A three-phase current phase command value θidc ^* which is a phase of the value is calculated.
θidc = tan ⁻¹ (Id / Iq) (8)
θidc ^* = tan ⁻¹ (Id ^* / Iq ^* ) (9)

Then, with respect to (θidc ^* −θidc), a correction value Δθvdc of the voltage phase of the motor voltage applied to the motor 4 that can reduce the deviation is determined using a control law such as PI control or PID control.
The Vdc ^* command value calculation unit 205 calculates the target value Vdcs of the generated voltage from the following equation (10) based on the voltage command values Vd ^* and Vq ^* calculated by the Vd, Vq command value calculation unit 202.
Vdcs = (2√2 / √3) · √ (Vd ^{* 2} + Vq ^{* 2} ) (10)

Further, the deviation (Iq ^* −Iq) between the current command value Iq ^* of the q-axis current calculated by the Id, Iq command value calculation unit 201 and the actual current value Iq can be reduced by PI control. Then, a correction value (hereinafter referred to as a generation voltage correction value) ΔVdc of the generation voltage command value is determined. The sum of the target value Vdcs of the generated voltage and the generated voltage correction value ΔVdc is set as a generated voltage command value Vdc ^* , which is output to the above-described generator control unit 8D in FIG.
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, such as PID compensation, may be used.

Further, by adding a generation voltage correction value ΔVdc corresponding to the deviation of the q-axis current to the target value Vdcs of the generation voltage and setting this as a generation voltage command value Vdc ^* , the fluctuation range of the output voltage of the generator 7 If this becomes larger, this may cause hunting of the motor torque. That is, when the generator output voltage is hunted and the motor current is hunted, the field magnetic flux of the motor 4 fluctuates, and the current that flows into the motor 4 to generate the motor torque hunts. As a result, the motor induced voltage fluctuates, which corresponds to the impedance fluctuating. Therefore, the generator operating point may move on the output possible characteristic line, and further hunting of the generator output voltage may be promoted.

Therefore, it is preferable that this feedback loop is made slower with respect to the generator field current response, whereby the generator control is accompanied by feeding back the deviation of the q-axis current with respect to the generated voltage command value Vdc ^* . Hunting can be avoided. The output possible characteristic line is an output characteristic line at which the generator 7 can operate when a certain field current is applied at a certain rotational speed.

In the voltage phase command value calculation unit 206, based on the d-axis voltage command value Vd ^* and the q-axis voltage command value Vq ^* calculated by the Vd, Vq command value calculation unit 202, the voltage phase command value tan ⁻¹ (Vd ^* / Vq ^* ) is calculated, and the sum of this and the voltage phase correction value Δθvdc calculated by the phase F / B control unit 204 is used as the voltage phase command value θ1, which is output to the sine wave command value calculation unit 207. To do.
In the sine wave command value calculation unit 207, the three-phase sine wave voltage is based on the magnetic pole position signal θ 0 output from the resolver connected to the motor 4 and the voltage phase command value θ 1 calculated by the voltage phase command value calculation unit 206. Command values Vu ^* , Vv ^* , Vw ^* are calculated.

The PWM control unit 208 converts the three-phase sine wave voltage command values Vu ^* , Vv ^* , and Vw ^* calculated by the sine wave command value calculation unit 207 into the generated voltage command value Vdc calculated by the Vdc ^* command value calculation unit 205. Normalize with ^* , compare this with a triangular wave, calculate the PWM command, and generate a switching signal to be output to the inverter 9.
As described above, in the triangular wave comparison, in the present embodiment, the generated voltage command value Vdc ^* that is the DC voltage command value to be generated by the generator 7 is used, for example, in the case of the U phase, Vu ^* / Vdc ^* A sine wave amplitude is normalized, and a U-phase switching signal is output by comparing the normalized sine wave command value with a triangular wave. Thereby, the impedance of the inverter 9 viewed from the generator 7 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 each motor rotation speed Nm.

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. Since the PWM wave voltage is generated based on the normalized sine wave command value as described above, the PWM wave voltage normalized by the generated voltage command value Vdc ^* is applied to the motor 4 as an application voltage with a fixed modulation rate. Will be.
The field current command value calculation unit 209 calculates a field current command value If ^* based on the motor rotational speed Nm and outputs the calculated field current command value If ^* to the field flux calculation unit 210. The magnetic flux is calculated and output to the Vd, Vq command value calculation unit 202 described above.

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.

Here, as described above, when the PWM control unit 208 performs the triangular wave comparison, the generated voltage command value Vdc ^* is used, for example, the sine wave amplitude is normalized by Vu ^* / Vdc ^* , and the inverter impedance Since the phase of the d-axis and q-axis current values to the motor 4 can be controlled, the absolute values of the d-axis and q-axis current values cannot be controlled.

However, not only the target value Vdcs of the generated voltage according to the torque command value Tt and the motor rotation speed Nm but also the generated voltage command value Vdc in consideration of the deviation between the actual current value Iq of the q-axis current and the current command value Iq ^{*. Since *} is set and the input voltage from the generator 7 side is adjusted by this, as a result, it becomes equivalent to controlling the magnitude of the current value of the d-axis and the q-axis. The current value can be made to follow the current command value.

In particular, the feedback to the generated voltage command value Vdc ^* is performed using the q-axis current acting as a torque component, not the d-axis current that causes the motor loss, so that the input voltage from the generator 7 is the q-axis. By operating so that the actual current value Iq is equal to the current command value Iq ^* , the torque component is operated so as to match the target value, thereby improving the torque accuracy. .
Further, the three-phase current phase θidc calculated from the ratio Id / Iq of the actual current values of the d-axis current and the q-axis current is the three-phase current calculated from the ratio Id ^* / Iq ^* of these current command values. Since the voltage phase of the voltage applied to the motor 4 is corrected so as to match the phase command value θidc ^* , the three-phase current phase θidc can be made to follow the command value θidc ^* of the three-phase current phase.

Here, simply by making the three-phase current phase θidc coincide with the command value θidc ^* of the three-phase current phase, the magnitudes of the current values Id and Iq of the d-axis and q-axis are changed to the current command values Id ^* and Iq. ^{* Although} it is not possible to follow the current value Iq ^* , the q-axis current value Iq can be made to follow the current command value Iq ^* by adjusting the power generation voltage command value Vdc ^* as described above. By combining the correction of the value Vdc ^{* and} the correction of the voltage phase command value of the voltage applied to the motor 4, as a result, the magnitude of the d-axis current value Id follows the current command value Id ^*. That is, the d-axis and q-axis current values Id and Iq can be made to follow the current command values Id ^* and Iq ^* in both magnitude and phase.

Next, the operation of the first embodiment will be described.
FIG. 8 shows a case where feedback is performed on the generated voltage command value Vdc ^* and the voltage phase of the voltage applied to the motor 4 according to the first embodiment, and FIG. 9 shows each signal when the feedback control is not performed. 8 and 9, (a) is the voltage phase θ, (b) is the generated voltage command value Vdc ^* (solid line) and the actual generated voltage Vdc (broken line), (c ) Is the d-axis current command value Id ^* (solid line) and the actual d-axis current value Id (broken line), (d) is the q-axis current command value Iq ^* (solid line) and the actual q-axis current value Iq (broken line), It represents.

The motor control unit 8E determines d-axis and q-axis current command values Id ^* and Iq ^* according to the torque command Tt and the motor rotational speed Nm, and determines the d-axis and the q-axis according to the current command values Id ^* and Iq ^*. The q-axis voltage command values Vd ^* and Vq ^* are calculated.
Then, the generated value target value Vdcs calculated based on the d-axis and q-axis voltage command values Vd ^* and Vq ^* corresponding to the torque command Tt and the motor rotation speed Nm, the current command value Iq ^* of the q-axis current, and the actual value. The sum of the generation voltage correction value ΔVdc for suppressing the deviation (Iq ^* −Iq) from the current value Iq is output to the generator side as the generation voltage command value Vdc ^* .
As a result, the generator 7 is controlled so as to output a generated voltage that can suppress the deviation (Iq ^* −Iq) between the current command value Iq ^* of the q-axis current and the actual current value Iq. The current value Iq is controlled so as to follow the current command value Iq ^* .

Further, the three-phase current phase command value θidc ^* (= tan ⁻¹ (Id ^* / Iq ^* )) calculated from the ratio Id ^* / Iq ^* of the current command values of the d axis and the q axis, and the d axis and the q axis Voltage phase correction value Δθvdc for suppressing the deviation (θidc ^* −θidc) from the three-phase current phase θidc (= tan ⁻¹ (Id / Iq)) calculated from the actual current value ratio Id / Iq And the sum of the correction value Δθvdc and the voltage phase command value tan ⁻¹ (Vd ^* / Vq ^* ) calculated from the voltage command values Vd ^* and Vq ^{* of} the d-axis and the q-axis, The command value θ1 is set, and the three-phase sine wave voltage command values Vu ^* , Vv ^* , Vw ^* are calculated based on the voltage phase command value θ1 and the magnetic pole position signal θ0 of the motor 4.
That is, a three-phase sinusoidal voltage command value that can suppress a deviation between the three-phase current phase command value θidc ^* and the three-phase current phase θidc is calculated, and the ratio Id between the d-axis and q-axis current command values is calculated. ^{The control is performed so that *} / Iq ^* and the ratio Id / Iq of the actual current values of the d-axis and the q-axis coincide.

For this reason, as shown in FIG. 8, the generated voltage command value Vdc ^{* with} respect to the deviation (Iq ^* −Iq) (FIG. 8D) between the current command value Iq ^* of the q-axis current and the actual current value Iq. The voltage applied to the motor 4 with respect to the deviation between the d-axis and q-axis current command values Id ^* Iq ^* vector and the d-axis and q-axis actual current values IdIq vector is increased and decreased (FIG. 8B). The phase θ of FIG. 8 (FIG. 8A) increases or decreases, whereby the IdIq vector follows the Id ^* Iq ^* vector, and as shown in FIGS. 8C and 8D, the d-axis The q-axis actual current values Id and Iq follow the current command values Id ^* and Iq ^* .

On the other hand, when the feedback according to the q-axis current and the feedback according to the ratio between the q-axis and the d-axis current are not performed on the generated voltage command value Vdc ^* and the voltage phase command value θ1, for example, parameter error or Due to voltage error, temperature error, etc., as shown in FIGS. 9C and 9D, the actual current values Id and Iq of the d-axis current value and the q-axis current value and the command values Id ^* and Iq ^* Even if there is a deviation, since the motor control unit 8E controls the motor 4 by the load fixing method and does not feed back the three-phase alternating current, this deviation is the generated voltage command value Vdc ^* (FIG. 9). (B) and the voltage phase of the voltage applied to the motor 4 (FIG. 9A) are not reflected, and the actual current values Id and Iq of the d-axis and the q-axis are converted into the current command values Id ^* and Iq ^*. It is difficult to match the torque to ensure torque accuracy There is a possibility that can not be Rukoto.

However, as described above, in the first embodiment of the present invention, the generated voltage command value Vdc ^* and the voltage phase of the voltage applied to the motor 4 are corrected based on the d-axis and q-axis current values. , D-axis and q-axis current values Id and Iq can be made to follow the current command values Id ^* and Iq ^* with higher accuracy. Therefore, it is possible to improve the torque accuracy in the motor torque control of the motor 4.
Therefore, even when the motor 4 is driven and controlled by the load fixing control method in which the motor 4 is driven and controlled only by the voltage phase control of the voltage applied to the motor 4, the torque control accuracy can be improved. it can.

  Therefore, in the case of the load fixing control method, since the load of the inverter is fixed and the voltage increase and the current increase of the generator can be maintained in a one-to-one relationship, the torque command value fluctuates greatly. Since it is possible to prevent a drop in the generated voltage and an overvoltage and to realize stable motor torque control, it is possible to realize stable motor torque control in this way, and as described above, By performing feedback according to the q-axis current or the ratio of the q-axis and d-axis current, the control accuracy of the motor torque control can be further improved.

Moreover, since the inverter phase control is sufficiently fast compared to the generator field current control, even when the power generation capacity of the generator 7 is low, the q-axis current becomes a negative value and a reverse torque is reached. Thus, an AC motor output equivalent to the power generation capability of the generator 7 can be obtained.
Further, as described above, the output of the generator 7 is controlled by correcting the generated voltage command value Vdc ^* of the generator 7 according to the deviation between the q-axis actual current value Iq and the current command value Iq ^*. Therefore, it is possible to easily correct the output power of the generator 7.

In the first embodiment, the feedback is based on the q-axis current value based on the generated voltage command value Vdc ^* and the ratio between the d-axis and q-axis current values by adjusting the voltage phase to the motor 4. Although the case where feedback is performed together has been described, the AC motor output equivalent to the power generation capability of the generator 7 can be obtained by adjusting the power generation voltage command value Vdc ^* and adjusting the input voltage from the generator 7 side. Therefore, it is possible to improve torque accuracy.

In the first embodiment, the ratio of the d-axis and q-axis current values is taken and converted into a current phase, and then the current phase θidc of the actual current value and the current phase θidc of the current command value are set. ^{Although the} case where feedback is performed on the voltage phase of the voltage applied to the motor 4 so as to coincide with ^* has been described, the present invention is not limited to this, and although it is simple, the actual current values of the d-axis and the q-axis Feedback may be performed on a deviation between the ratio of the current command value and the ratio of the current command value.
In the first embodiment, the case where the sine wave amplitude is normalized using the generated voltage command value Vdc ^* has been described. However, the present invention is not limited to this as long as the inverter impedance is fixed. For example, the present invention can be applied to the case of normalizing the sine wave amplitude using the voltage at the operating point with the best motor efficiency.

Next, a second embodiment of the present invention will be described.
In the second embodiment, in the first embodiment, the motor control unit 8E applies load fixing control for stopping voltage modulation as a control method of the motor 4, whereas rectangular wave control is applied. Is applied. In FIG. 3 in the first embodiment, the configuration is the same except that the configuration of the motor control unit 8E is different. Therefore, the same reference numerals are given to the same units, and detailed descriptions thereof are omitted.

FIG. 10 is a block diagram showing details of the motor control unit 8E in the second embodiment.
The motor controller 8E in the first embodiment shown in FIG. 7, Vdc ^* in place of the command value calculating section 205, Vdc ^* command value calculation section 205a is provided, also, a sine wave command value calculating section 207 and the PWM Instead of the control unit 208, a switching pattern selection unit 211 is provided.
The Vdc ^* command value calculation unit 205a calculates the target value Vdcs of the generated voltage from the following equation (11) based on the voltage command values Vd ^* and Vq ^* calculated by the Vd, Vq command value calculation unit 202.
Vdcs = (2√2 · π / 4√3) · √ (Vd ^{* 2} + Vq ^{* 2} ) (11)

Thereafter, the current command value Iq ^* of the q-axis current calculated by the Id, Iq command value calculation unit 201 is the same as the process in the Vdc ^* command value calculation unit 205 in the first embodiment. A power generation voltage correction value ΔVdc is determined based on the deviation (Iq ^* −Iq) from the actual current value Iq, and the sum of the power generation voltage target value Vdcs calculated from the equation (11) and the power generation voltage correction value ΔVdc is calculated. The voltage command value Vdc ^* is set and output to the generator control unit 8D shown in FIG.

  In addition, the switching pattern selection unit 211 performs a magnetic phase position signal θ0 output from the resolver connected to the motor 4 and the voltage phase command value calculated by the voltage phase command value calculation unit 206 in the same procedure as the known rectangular wave control. The sum with the value θ1 is calculated as the motor voltage phase θv. And according to the magnitude | size of this motor voltage phase (theta) v, an applicable thing is selected among six switching patterns, and the switching control of the three-phase power element of the inverter 9 is carried out. That is, in order to perform 180-degree energization rectangular wave control, as shown in FIG. 11, the section is divided into six sections having different switching patterns for each electrical angle of 60 degrees, that is, section 1 to section 6.

FIG. 12 shows the switching pattern of each section. For example, if the motor voltage phase θv is in the range of −30 degrees to 30 degrees, section 1 is applied, and a switching signal is given so that the U phase becomes a positive voltage and the V phase and the W phase become negative voltages. Since the voltage command vector V shown in FIG. 11 is in the section 3 region, the switching pattern corresponding to the section 3 is selected from the switching pattern of FIG. 12, and the V phase is a positive voltage, the U phase, and the W phase. A switching signal is output so that becomes a negative voltage.
Then, the inverter 9 generates a rectangular wave voltage corresponding to the switching signal and applies it to the motor 4, thereby driving the motor 4 to a rectangular wave voltage. That is, a rectangular wave voltage fixed with a high PWM duty ratio is applied to the motor 4 as the applied voltage with a fixed modulation rate.

That is, in the second embodiment, the voltage phase command value tan ⁻¹ (Vd ^* / Vq ^* ) calculated based on the d-axis voltage command value Vd ^* and the q-axis voltage command value Vq ^* , Voltage phase correction value for matching the actual current value ratio Id / Iq of the d-axis and q-axis current values with the current command value ratio Id ^* / Iq ^* calculated by the phase F / B control unit 204 The sum of Δθvdc is the voltage phase command value θ1, and the motor 4 is rectangular-wave controlled according to the voltage phase command value θ1.

Therefore, in this second embodiment as well, although the amplitude of the voltage applied to the motor 4 is not adjusted, the torque accuracy can be improved by controlling the voltage phase by the correction value Δθvdc. . Also in this case, the generated voltage command value Vdc ^*, because they were corrected in accordance with the q-axis current value, the generated voltage command value Vdc ^* to follow the q-axis current value Iq on the current command value Iq ^* The torque accuracy is further improved by controlling the voltage phase so that the ratio Id / Iq of the actual current values of the d-axis and q-axis currents coincides with the ratio Id ^* / Iq ^{* of the} current command values. Can do.

It is a schematic structure figure showing an embodiment of the present invention. It is an example of the field current drive circuit of a generator. It is a block diagram which shows the detail of 4WD controller of 1st Embodiment. It is a block diagram which shows the detail of the generator control part of FIG. 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 the motor control part of 1st Embodiment. It is a change state of each signal value when feedback is performed according to the first embodiment. It is a change state of each signal value when feedback is not performed according to the first embodiment. It is a block diagram which shows the detail of the motor control part of 2nd Embodiment. It is a figure which shows the relationship between a voltage vector and a switching pattern area. It is a figure which shows the switching pattern of each voltage phase area.

Explanation of symbols

1L, 1R Front wheel 2 Engine 3L, 3R Rear wheel 4 Motor 6 Belt 7 Generator 8 4WD controller 8A Target motor torque calculation unit 8B Generator supply power calculation unit 8C Power generation current command calculation unit 8D Generator control unit 8E Motor control unit 8F TCS control unit 8G Clutch control unit 9 Inverter 10 Junction box 11 Reducer 12 Clutch 27FL, 27FR, 27RL, 27RR Wheel speed sensor 101 P control unit 102 I control unit 103 FF control unit 104 Control amount addition unit 105 Field control unit 201 Id, Iq command value calculation unit 202 Vd, Vq command value calculation unit 203 3 phase / 2 phase conversion unit 204 Phase F / B control unit 205, 205a Vdc ^* command value calculation unit 206 voltage phase command value calculation unit 207 sine wave command value calculation Unit 208 PWM control unit 209 Field current command value Flux calculating unit field calculation unit 210 211 switching pattern selector

Claims (5)

A heat engine that drives the main drive wheels;
A generator driven by the heat engine,
An AC motor in which the power of the generator is supplied via an inverter to drive the driven wheels;
Motor required power calculating means for calculating required motor power required by the AC motor;
Generator control means for controlling the generator so as to generate the required motor power calculated by the required motor power calculation means;
A motor control means for controlling the AC motor by applying a voltage with a fixed modulation rate for supplying a current corresponding to a predetermined current command value, and a vehicle drive control device comprising:
Current detecting means for detecting an actual current value flowing through the AC motor;
Based on the deviation between the q-axis component of the actual current value detected by the current detection means and the q-axis component of the current command value, the q-axis component of the actual current value and the q-axis component of the current command value are Generated power correction means for correcting the control amount by the generator control means so as to match,
The voltage applied to the AC motor is adjusted so that the ratio of the d-axis component and the q-axis component of the actual current value detected by the current detection means matches the ratio of the d-axis component and the q-axis component of the current command value. Vehicular drive control device comprising: voltage phase correction means for correcting the voltage phase . The voltage phase correction means calculates a deviation between the current phase of the actual current value detected by the current detection means and the current phase of the current command value,
2. The vehicle drive according to claim 1, wherein the voltage phase of the applied voltage is corrected based on the deviation so that the current phase of the actual current value matches the current phase of the current command value. Control device. The generator control means controls the field of the generator so that the generated voltage of the generator matches the generated voltage command value specified by the required power of the motor,
The vehicle drive control device according to claim 1, wherein the generated power correcting means corrects the generated voltage command value . 4. The vehicle drive control device according to claim 1, wherein the motor control unit applies a PWM wave voltage having a fixed modulation rate as the applied voltage . 5. 4. The vehicle drive control device according to claim 1, wherein the motor control unit applies a rectangular wave voltage as the applied voltage . 5.

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