JP2006306144A - Drive control device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drive control device for a vehicle capable of controlling stably a motor torque by combination of a power generator with an alternating current motor. <P>SOLUTION: Motor-requiring electric power Pm necessary in the motor 4 is calculated based on a torque command value Tt and a motor rotational speed Vm, and a field of the generator 7 is controlled based on the motor-requiring electric power Pm. A target output electric power PG to be output from the generator 7 is calculated therein based on the motor-requiring electric power Pm, an outputtable characteristic line St including a target operation point (Vt, It) of the generator 7 is set based on the target output electric power PG, and a field current fg of the generator 7 is controlled to conform an outputtable characteristic line S including the present operation point (V, I) determined based on an output voltage V and an output current I from the generator 7 with the target outputtable characteristic line St. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vehicle drive control device that drives a generator with an internal combustion engine (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, there is known a device in which a driven shaft is driven by a direct current motor driven by electric power of a generator and a drive torque is controlled by controlling a field current of the direct current motor. (For example, refer to 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 there is a limit in the life of brushes of DC motors, there is a limit in the increase in armature current, and there is an unresolved problem that it is difficult to apply to heavy vehicles or that 4WD performance cannot be improved. .

  By the way, it is conceivable to control the motor torque by applying an AC motor + inverter configuration instead of a DC motor. However, it is generally known that the control response of the generator is low and the motor control response by the inverter is high. Thus, when such a generator and an inverter are combined, the output voltage and output current of the generator may vary depending on the control state of the inverter serving as an electric load.

Therefore, if the power generation amount of the generator is controlled based on the output voltage and output current of the generator that has fluctuated, the control point fluctuates without the generator control being stabilized, and the desired driving force cannot be stably generated. There is an unresolved issue.
Therefore, the present invention has been made paying attention to the unsolved problems of the above-described conventional example, and a vehicle drive control device capable of performing stable motor torque control by a combination of a generator and an AC motor. It is intended to provide.

  In order to achieve the above object, a vehicle drive control device according to the present invention calculates a target output power to be output from a generator by a target output power calculation means based on a motor required power required by an AC motor. Based on the target output power calculated by the target output power calculation means, a characteristic generator setting means sets a target generator output characteristic line using the rotational speed and field current of the generator as parameters, and the characteristic Based on the generator output characteristic line set by the line setting means, the field control means controls the field of the generator.

  According to the present invention, the target output power to be output from the generator is calculated from the power required by the AC motor, and the generator field is calculated based on the target generator output characteristic line set from the target output power. Therefore, even if the load on the generator side fluctuates due to the control movement on the inverter side, the target value of the generator does not fluctuate. For this reason, fluctuations in the generator control system can be prevented, stable generator control can be performed, and the problem that a desired drive force cannot be generated stably can be avoided.

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 that is an internal combustion engine, and left and right rear wheels 3L and 3R are driven by a motor 4. Possible driven wheel.

  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 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 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, in a state where the generator output is lower than the battery voltage Vb, it becomes a separately excited region and the battery voltage Vb becomes the power source of the field coil 7b. That is, the supply voltage to the field coil 7b is Vb. Further, when the generator output increases and the output voltage Vg becomes equal to or higher than the battery voltage Vb, the output voltage Vg of the generator is selected as a self-excited region and becomes the power source of the field coil 7b, and is supplied to the field coil 7b. The supply voltage is Vg.

Thus, 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 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 control unit 8B, a motor control unit 8C, a TCS control unit 8D, and a clutch control unit 8E.
The target motor torque calculation unit 8A calculates the motor torque command value Tt from the wheel speed difference between the front and rear wheels calculated based on the wheel speed signals of the four wheels and the accelerator pedal opening signal.
FIG. 4 is a block diagram showing details of the target motor torque calculator 8A. First, the front / rear rotation difference calculation unit 81 calculates the front / rear rotation difference ΔV based on the following equation based on the wheel speed signals Vfr to Vrr of the four wheels.
ΔV = (Vfr + Vfl) / 2− (Vrr−Vrl) / 2 (1)

Then, based on the front-rear rotation difference ΔV, the map stored in advance by the first motor driving force calculation unit 82 is referred to calculate the first motor driving force TΔV and output it to the select high unit described later. The first motor driving force TΔV is set so that the front-rear rotation difference ΔV is increased and proportionally larger.
The vehicle speed calculation unit 83 calculates a vehicle speed signal V by selecting low the wheel speed signal of the four wheels and the total driving force F generated by the vehicle. Here, the total driving force F is obtained by the sum of the front wheel driving force estimated from the torque converter slip ratio and the rear wheel driving force estimated from the motor torque command value Tt.

  The second motor driving force calculation unit 84 calculates the second motor driving force Tv. Specifically, it is calculated with reference to a map stored in advance based on the vehicle speed V output from the vehicle speed calculation unit 83 and the accelerator opening degree Acc. The second motor driving force Tv is set so as to increase as the accelerator opening Acc increases and to decrease as the vehicle speed V increases.

Next, in the select high unit 85, the first motor driving force TΔV output from the first motor driving force calculation unit 82 and the second motor driving force Tv output from the second motor driving force calculation unit 84 are obtained. The selected high value is output to the rear wheel TCS control unit 86 as the target torque Ttt.
Then, based on the rear wheel speeds Vrl and Vrr and the vehicle speed V, rear wheel traction control control is performed by a known method, and a final torque command value Tt of the motor 4 is output.

The motor control unit 8C performs known vector control shown in FIG. 5 from the torque command value Tt and the motor rotation speed Vm. Then, the switching control signal of the three-phase power element is output to the inverter 9 to control the three-phase alternating current.
The TCS controller 8D generates an engine generated drive torque demand signal for the ECM by a known method based on the engine generated drive torque demand signal Tet from the engine torque controller (ECM), the front wheel rotational speeds Vfr and Vfl, and the vehicle speed V. Front wheel traction control control is performed by returning Te.
The clutch control unit 8E controls the state of the clutch 12 and controls the clutch 12 to be in a connected state while determining that it is in the four-wheel drive state.

FIG. 6 is a block diagram showing details of the generator control unit 8B that performs power generation control of the generator 7.
The generator control unit 8B includes a motor required power calculation unit 101, a target generated power calculation unit 102, a generated power limit unit 103, a target generated power determination unit 104, a target operating point setting unit 105, a current operation check. The output unit 106 and the generated power control unit 107 are configured to control the field current Ifg of the generator 7.
Based on the torque command value Tt calculated by the target motor torque calculator 8A and the motor rotation speed Vm, the motor required power calculator 101 calculates the power Pm required for the motor 4 based on the following equation.
Pm = Tt × Vm (2)

Based on the required motor power Pm output from the required motor power calculation unit 101, the target generated power calculation unit 102 calculates the required generator power Pg that the generator 7 should output based on the following equation.
Pg = Pm / Иm (3)
Here, Иm is the motor efficiency. That is, the generator required power Pg must be output by the motor efficiency more than the motor required power Pm.

The generated power limiting unit 103 outputs generated power limit values PL1 and PL2. The power limit value PL1 is an upper limit value for preventing the generated power from exceeding the power determined according to the transmittable torque of the belt that drives the generator 7, and is calculated based on the following equation.
PL1 = Tb × ωg × Иg (4)
Here, Tb is the torque that can be transmitted to the belt, ωg is the rotational speed of the generator 7, Иg is the generator efficiency, and PL1 is the maximum amount of power that the generator 7 can generate when the belt-transmittable torque is Tb. Equivalent to.
That is, as shown in FIG. 7A, the power limit value PL1 is proportionally increased as the rotational speed ωg of the generator 7 increases.

The power limit value PL2 is an upper limit value for preventing the generated power from exceeding electric power that may cause engine stall or drivability deterioration due to excessive engine load. This limit value PL2 is given from an engine torque controller (ECM).
As shown in FIG. 7B, the power limit value PL2 is calculated to be larger as the rotational speed ωg of the generator 7 is larger and the accelerator opening Acc is larger.
Then, the calculation results of the target generated power calculating unit 102 and the generated power limiting unit 103 are input to the target generated power determining unit 104, the generator required power Pg and the power limit values PL1 and PL2 are selected, and the generator A target output power PG is calculated.

FIG. 7C shows a case where the generator required power Pg is the smallest of the generator required power Pg and the power limit values PL1 and PL2. In this case, the generator required power Pg at the current speed is The target output power PG is selected.
The target operating point setting unit 105 first calculates a motor torque command value T based on the following expression based on the target output power PG output from the target generated power determining unit 104, that is, the motor usable power.
T = (PG × Иm) / Vm (5)

  Next, the input voltage and input current of the inverter 9 that can efficiently generate the motor torque command value T, that is, the target voltage Vt and the target current It of the generator 7 are determined within the range of the motor usable power PG. Specifically, as shown in FIG. 8, the intersection of the constant power line P corresponding to the motor usable power PG and the maximum efficiency operating dotted line η indicated by the broken line is a target operating point (Vt, It) of the generator 7. Select as

In general, the generator efficiency is high at high voltage and low current, and the motor efficiency does not change much except when it is at a very low current. It is desirable to work. Further, since the system has an upper limit voltage V _max (for example, 60 V) and an upper limit current I _max (determined by the inverter element rating and the generator / motor design. For example, 30 A), the voltage becomes the upper limit voltage V _max . When approaching, an operating point at which the current value increases with a substantially constant or slight increase in voltage is selected, and eventually the current value increases up to the upper limit current I _max . The continuous line of these operating points is the maximum efficiency operating dotted line η, and this maximum efficiency operating dotted line η is stored in advance.

FIG. 9 is a diagram showing an operating point (voltage / current) at the output of the generator 7, that is, the input of the inverter 9. In FIG. The solid line in the figure is the generator output characteristic line (generator output possible characteristic line) with the generator rotational speed and field current as parameters, and when a field current at a certain rotational speed is given The generator generates a voltage / current on the output possible characteristic line.
Although the actual output possible characteristic line is a non-linear line, since the output possible characteristic line in the control region is monotonically decreasing, linear approximation is used in this embodiment. That is, the linear approximation formula of the output possible characteristic line is expressed by the following formula.
V = −a × I + V ₀ (6)
Here, V ₀ is a voltage axis intercept (V axis intercept), which is a voltage when the current is zero. Further, a is a constant set in advance from the characteristics of the generator. Note that a may be a variable constant whose parameters are the rotational speed and the magnitude of the field current in order to obtain high accuracy.

Next, the target V-axis intercept V ₀ t of the output possible characteristic line St including the target operating point (Vt, It) is calculated. Specifically, based on the target voltage Vt and the target current It, the target V-axis intercept V ₀ t is calculated based on the linear approximate expression Vt = −a × It + V ₀ t of the output possible characteristic line St.
The current operating point detector 106 calculates the V-axis intercept V ₀ of the output possible characteristic line S including the current operating point (V, I) shown in FIG. Specifically, based on the current voltage V and current I, the V-axis intercept V ₀ is calculated based on the linear approximate expression V = −a × I + V ₀ of the output possible characteristic line S.
The generated power control unit 107 controls increase / decrease in the field current Ifg of the generator 7 according to the magnitude relationship between the V-axis intercept V ₀ and the target V-axis intercept V ₀ t.

For example, even if the voltage and current of the generator change due to fluctuations in the input impedance on the inverter side, the voltage and current move on the output possible characteristic line of the generator, so the V-axis intercept does not change. Accordingly, by making the V-axis intercept V ₀ coincide with the target V-axis intercept V ₀ t, the difference between the current output possible characteristic line S and the target output possible characteristic line St is eliminated, and also due to control fluctuations on the inverter side. Even when the load on the generator side fluctuates, the fluctuation of the generator control system is prevented.
In FIG. 6, the processing of the target generated power calculating unit 102, the generated power limiting unit 103, and the target generated power determining unit 104 corresponds to the target output power calculating unit, and the processing of the target operating point setting unit 105 is the characteristic line setting unit. And the processing of the generated power control unit 107 corresponds to the field control means.

FIG. 10 is a block diagram showing the generated power control unit 107 in the first embodiment. The generated power control unit 107 in the first embodiment generates power while monitoring the actual generator field current Ifg so that the deviation between the target V-axis intercept V ₀ t and the V-axis intercept V ₀ becomes zero. The machine field current value is fed back.
First, the deviation [Delta] V ₀ and V-axis intercept V ₀ which from the target V-axis intercept V ₀ t and the current operating point detecting unit 106 from the target operating point setting part 105 is input to the PID controller 121, PID controller 121 The target field current Ift is output so that the deviation ΔV ₀ becomes zero.

In the present embodiment, a field current sensor as a field current detection means is provided to detect the actual generator field current Ifg. Then, a deviation ΔIf between the actual field current Ifg detected by the field current sensor and the target field current Ift is obtained and output to the PID control unit 122. The PID control unit 122 controls the real field current Ifg so that the deviation ΔIf becomes zero.
As a result, the V-axis intercept V ₀ matches the target V-axis intercept V ₀ t. That is, the generator 7 operates at an operating point at which the torque command value T corresponding to the target output power PG to be output from the generator 7 calculated from the power Pm required by the motor 4 can be efficiently generated. Will be.

  As described above, in the first embodiment, the target output power to be output by the generator is calculated from the power required by the AC motor, and the output possible characteristic line including the current operating point becomes the target output power. Since the field current of the generator is controlled so that it matches the output possible characteristic line including the target operating point of the generator set based on, even if the load on the generator side fluctuates due to the control movement on the inverter side The fluctuation of the field current command value of the generator can be eliminated. As a result, stable generator control can be performed by preventing fluctuations in the generator control system, and problems such as vibration problems caused by being directly connected to the engine and problems that a desired driving force cannot be generated stably are avoided. can do.

Further, since the output possible characteristic line of the generator is given as a linear line by a linear approximation expression, it is relatively easy to control the intercept of the current output possible characteristic line to coincide with the intercept of the target output possible characteristic line. In this way, it is possible to ensure that the current output possible characteristic line matches the target output possible characteristic line.
In addition, the field current of the generator is monitored, and feedback control is performed so that the actual field current follows the target field current, so that the intercept of the current output possible characteristic line is surely followed by the target intercept. Can be made.

  In the first embodiment, the case where the output possible characteristic line of the generator is a linear line and the current output possible characteristic line is made to follow the target output possible characteristic line has been described. However, the present invention is not limited to this. Instead, the relationship between the current output possible characteristic line and the target output possible characteristic line may be compared by a non-linear map so that the current output possible characteristic line follows the target output possible characteristic line. .

Next, a second embodiment of the present invention will be described.
In the second embodiment, the deviation between the target V-axis intercept and the current V-axis intercept is made zero by performing PWM control of the field current of the generator in the first embodiment described above. It is what.
FIG. 11 is a block diagram showing details of the generated power control unit 107 in the second embodiment.
First, the deviation ΔV ₀ between the target V-axis intercept V ₀ t and the V-axis intercept V ₀ is input to the PID control unit 123.

The PID control unit 123 controls the PWM duty ratio D of the field current drive circuit of the generator 7 according to the deviation ΔV ₀ . Specifically, the PWM duty ratio D is increased when V ₀ t> V ₀ , and the PWM duty ratio D is decreased when V ₀ t <V ₀ .
For example, the following PID control is performed.
D = α × (V ₀ t−V ₀ ) + β × ∫ (V ₀ t−V ₀ ) (7)

FIG. 12 is a characteristic diagram showing the relationship between the PWM duty ratio D and the field current Ifg. The horizontal axis represents the PWM duty ratio D and the vertical axis represents the field current Ifg. As shown in this characteristic diagram, when the duty ratio D is 0%, the field current Ifg does not flow, and as the duty ratio D approaches 100%, a lot of the field current Ifg flows.
This characteristic is such that the greater the field power supply voltage Vf, the greater the slope, and the smaller the field coil resistance, the greater the slope. If the generator output voltage Vg is less than or equal to the battery voltage Vb, Ifg = A × D, and when Vg> Vb, Ifg = a × Vf × D. Here, a is a constant.

The field current Ifg can be controlled by controlling the PWM duty ratio D output in this way by the PWM drive unit 124. As a result, the V-axis intercept V ₀ becomes the target V-axis intercept V ₀ t. Can be controlled.
As described above, in the second embodiment, since the field current of the generator is PWM-controlled, all the error factors of the field current control due to the field current voltage fluctuation and the field coil resistance value fluctuation are included. Since the control can be performed with a loop having a large actual output power and a target output power, it is not necessary to provide a field current sensor, and the cost can be reduced.

Next, a third embodiment of the present invention will be described.
In the third embodiment, the multiplication value of the field power supply voltage and the PWM duty ratio is feedback-controlled.
That is, the generated power control unit 107 in the third embodiment performs feedback control on the product (Vf × D) of the field power supply voltage Vf and the PWM duty ratio D by the PID control unit 123 in the second embodiment described above. Except that the PWM duty ratio D is output, the configuration is the same as that shown in FIG.

When the deviation [Delta] V ₀ between target V-axis intercept V ₀ t and V-axis intercept V ₀ is input to the PID controller 123, PID controller 123, PWM duty ratio is subjected to PID control shown in following formula (8) D is output.
Vf × D = α × (V ₀ t−V ₀ ) + β × ∫ (V ₀ t−V ₀ )
D = {α × (V ₀ t−V ₀ ) + β × ∫ (V ₀ t−V ₀ )} / Vf (8)
As described above, when Vg> Vb, the field current Ifg = a × Vf × D. From this relationship, it is possible to perform feedback control assuming that (Vf × D) is the field current Ifg.

  By the way, when the generator voltage Vg is less than or equal to the battery voltage Vb, the PWM duty ratio D is substantially proportional to the field current Ifg, but when the generator voltage Vg is greater than the battery voltage Vb, the field power supply voltage Vf increases. Therefore, the field current Ifg becomes large even with the same duty ratio D. In other words, in order to generate the same field current Ifg as when the generator voltage Vg is high in the region where the generator voltage Vg is high, it is necessary to reduce the PWM duty ratio D.

  In the present embodiment, feedback control is performed assuming that the product value (Vf × D) of the field power supply voltage and the PWM duty ratio is the field current Ifg. For example, in the region where the generator voltage Vg is high, the PWM duty ratio D is The weight of the PWM duty ratio can be set according to the magnitude of the field power supply voltage Vf, such as being set small. Thereby, for example, when a transition is made from a certain control point where Vg ≦ Vb to a certain control point where Vg> Vb, it is possible to prevent the occurrence of overshoot and output fluctuation of the power generation output.

As described above, in the third embodiment, since the product of the field power supply voltage Vf and the PWM duty ratio D is feedback-controlled, a control effect is obtained in which the field current Ifg is substantially feedback-controlled. be able to.
Further, in the region where the field power supply voltage Vf is large, the weight of the PWM duty ratio can be set smaller than that at the time of low voltage, so that appropriate control in consideration of the magnitude of the field power supply voltage can be performed. .

In each of the above embodiments, the case where the torque command value Tt calculated by the target motor torque calculation unit 8A is output to both the generator control unit 8B and the motor control unit 8C has been described. Instead, the torque command value Tt may be output only to the generator controller 8B.
In this case, as shown in FIG. 13 in detail of the block diagram of the generator / motor control unit 8F in FIG. 3, the target output power PG calculated by the target generated power determination unit 104 of the generator control unit 8B is converted into the motor control unit. Output to the target motor torque determination unit 201 of 8C. Then, the target motor torque determination unit 201 calculates a torque command value T based on the target output power PG based on the equation (5), and uses the torque command value T as the torque command value Tt. The vector control shown in FIG.

In each of the above embodiments, the case has been described in which the target operating point setting unit 105 is provided in the generator control unit 8B and the target V-axis intercept V ₀ t is set. However, the present invention is not limited to this. Based on the target output power PG calculated by the target generated power determining unit 104 of the machine control unit 8B, the motor control unit 8C sets the target V-axis intercept V ₀ t and outputs this to the generated power control unit 107. It may be.

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 of FIG. It is a block diagram which shows the detail of the target motor torque calculating part of FIG. It is a block diagram which shows the detail of the motor control part of FIG. It is a block diagram which shows the detail of the generator control part of FIG. It is a figure which shows the relationship between an electric power limit value and target output electric power. It is a figure explaining the selection method of a target operating point. It is a figure explaining the concept of generated electric power control. It is a block diagram which shows the detail of the generated electric power control part in 1st Embodiment. It is a block diagram which shows the detail of the generated electric power control part in 2nd, 3rd embodiment. It is a characteristic view which shows the relationship between PWM duty ratio D and field current Ifg. It is a block diagram which shows the other example of the generator and motor control part of FIG.

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 control unit 8C Motor control unit 8D TCS control unit 8E Clutch control unit 8F Generator / motor control Unit 9 Inverter 10 Junction box 11 Reducer 12 Clutch 27FL, 27FR, 27RL, 27RR Wheel speed sensor 101 Motor required power calculation unit 102 Target generated power calculation unit 103 Generated power limit unit 104 Target generated power determination unit 105 Target operating point setting unit 106 current operating point detection unit 107 generated power control unit

Claims (8)

A vehicle drive control device comprising: an internal combustion engine that drives main driving wheels; a generator that is driven by the internal combustion engine; and an AC motor that is supplied with electric power from the generator via an inverter to drive the driven wheels. In
Based on the required motor power required by the AC motor, the target output power calculating means for calculating the target output power to be output by the generator, and the target output power calculated by the target output power calculating means , Based on the target generator output characteristic line set by the characteristic line setting means, characteristic line setting means for setting a target generator output characteristic line with the rotational speed and field current of the generator as parameters And a vehicle control device for controlling a field of the generator.   The field control means controls the field of the generator so that a current generator output characteristic line including an operating point determined from the output voltage and output current of the generator becomes the target generator output characteristic line. The vehicle drive control device according to claim 1, wherein the vehicle drive control device is controlled.   The generator output characteristic line is approximated to a linear line, and the field control means is configured so that the intercept of the current generator output characteristic line becomes the intercept of the target generator output characteristic line. The vehicle drive control device according to claim 2, wherein the vehicle drive control device is controlled.   Field current detecting means for detecting a field current of the generator, and the field control means is configured to detect the field current so that the current generator output characteristic line becomes the target generator output characteristic line. 4. The vehicle drive control device according to claim 2, wherein the field current detected by the detection means is feedback-controlled.   4. The field control means controls the field of the generator with a PWM duty ratio so that the current generator output characteristic line becomes the target generator output characteristic line. The vehicle drive control device described in 1.   6. The vehicle drive control device according to claim 5, wherein the field control means sets the PWM duty ratio to be smaller as the supply voltage to the field coil of the generator is larger.   The generator is driven by a belt, and the target output power calculation means limits the upper limit of the target output power by a power limit value corresponding to the upper limit of the transmittable torque of the belt that drives the generator. The vehicle drive control device according to any one of claims 1 to 6.   The target output power calculation means limits the upper limit of the target output power with a power limit value that can prevent drivability deterioration due to excessive load of the internal combustion engine. The vehicle drive control device described in 1.

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