JP2002171605A - Control device for front and rear wheel drive vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device for a front and rear wheel drive vehicle, capable of recovering an electric energy in just proportion regardless of a vehicle speed, while using a compact motor and also a compact energy storage device, and of adequately maintaining a remaining charged electricity of the energy storage device. SOLUTION: The control device 1 for the front and rear wheel drive vehicle 2 which drives the front wheels and the rear wheels by an engine 3 and an electric motor 4 respectively is equipped with a ECU 20. The ECU 20 calculates a state of charge SOC of the battery 9. When the electric energy is recovered, the ECU 20 controls recovery quantity of the electric energy by controlling a connecting force FCL of a clutch 10 for a value with which the clutch 10 is connected in a state without a slip when a vehicle speed Vcar is a first limit value VLMT1 or less, or for a value with which the clutch 10 is connected in a state with a slip depending on the SOC when the vehicle speed Vcar is a second limit value VLMT2 or more.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric motor for driving one of the front and rear driving wheels by an engine and the other by an electric motor and generating electric energy by the electric motor to drive the driving energy of the electric motor. The present invention relates to a control device for a front and rear wheel drive vehicle that is collected as a vehicle.

[0002]

2. Description of the Related Art Conventionally, this type of control device has
What is described in 000-79833 is known. In this front and rear wheel drive vehicle, the front wheels are driven by an engine connected to the front wheels, and the rear wheels are driven by an electric motor connected to the rear wheels via a rear differential mechanism. In this control device, when the front and rear wheel drive vehicle is decelerating, for example, the electric motor performs a power generation operation as a generator, so that the traveling energy is collected as electric energy and charged into the capacitor. The electric energy of the capacitor drives the electric motor as needed.

As another control device for a front-rear-wheel drive vehicle, a control device disclosed in Japanese Patent Application Laid-Open No. H11-291774 is known. In this front and rear wheel drive vehicle, the engine is connected to the front wheels, and the electric motor is connected to the rear wheels via a speed reduction mechanism, a clutch and a rear differential mechanism. In this control device, when starting, the clutch is engaged and only the rear wheels are driven by the electric motor to start the front and rear wheel drive vehicle, and after the start, the accelerator opening becomes larger than the predetermined opening. Then, the engine is started and the driving of the front wheels is started. During traveling, when the rotation speed on the output side of the clutch exceeds the rotation speed on the input side, that is, when the vehicle speed exceeds the rotation speed of the rear wheel due to the rotation of the electric motor, the clutch controls the rear wheel and the electric motor. Is cut off. Further, after the driving of the front wheels by the engine is started, when the vehicle speed exceeds a predetermined value, the electric motor is stopped.

[0004]

In the former control device, when the required rear wheel driving force is to be ensured by using a relatively small electric motor, the reduction ratio of the rear differential mechanism is set to a large value. Must be set to In such a case, the electric motor always rotates at a higher rotational speed than the rear wheels due to the reduction ratio of the rear differential mechanism during traveling in a wide speed range from the start to the maximum speed, Since the rotation area of the electric motor must be extremely wide, there is no durability in terms of durability. Therefore, in order to ensure the durability of the electric motor, the size of the electric motor is inevitably increased, which increases the manufacturing cost and makes it difficult to secure a mounting space. In addition, with the increase in the size of the electric motor, the regenerative capacity of the electric power increases,
It is necessary to increase the capacity of the power storage device, which also increases in size.

In order to solve the above problem, it is conceivable to apply the latter control device to the former control device. That is, by providing a clutch between the electric motor and the rear wheels, and controlling the clutch, when the vehicle speed is less than a predetermined value, the electric motor and the electric motor are engaged, and when the vehicle speed reaches a predetermined value or more, It is conceivable to cut off the connection between the rear wheel and the electric motor. In such a case, the rotation area of the electric motor can be set narrower, so that a smaller electric motor can be used. However, since the power cannot be regenerated in a vehicle speed range equal to or higher than a predetermined value due to the disconnection of the clutch, even when the amount of power stored in the power storage device (hereinafter referred to as “remaining charge”) is insufficient, Electric power regeneration cannot be performed until the vehicle speed falls below a predetermined value. As a result, when the vehicle speed falls below the predetermined value, even if the clutch is engaged,
There is a possibility that the driving force of the electric motor cannot be properly secured.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and when one of the front and rear wheels is driven by an engine and the other is driven by an electric motor, a relatively small electric motor and a power storage device are used. , The electric energy can be recovered without excess or shortage regardless of the vehicle speed, and the charge remaining amount of the power storage device can be maintained at an appropriate level, thereby appropriately securing the driving force of the electric motor. An object of the present invention is to provide a control device for a front and rear wheel drive vehicle that can be used.

[0007]

In order to achieve this object, according to the first aspect of the present invention, one of the front and rear drive wheels (for example, front wheels WFL, WFR in the embodiment (hereinafter the same in this section)) is used. ) Is driven by the engine 3, and the other (rear wheels WRL, WRR) are driven by the electric motor 4, and the traveling energy can be recovered as electric energy for driving the electric motor 4 by the electric motor 4. The control device 1 of the front and rear wheel drive vehicle 2 that charges the collected electric energy to the power storage device (battery 9), and connects the other drive wheels (rear wheels WRL, WRR) and the electric motor 4 to each other. A clutch 10 configured to disengage and vary the engagement force FCL, and a remaining charge detecting means (E) for detecting the remaining charge SOC of the power storage device (battery 9).
CU20, step 6) and the vehicle speed V of the front and rear wheel drive vehicle 2
The vehicle speed detection means (ECU 20, wheel speed sensor 22) for detecting car, and the engagement force FCL of the clutch 10 during the recovery of electric energy, when the detected vehicle speed Vcar is less than a predetermined value (first limit value VLMT1 or less) ), The clutch 10 is set to a value that can be engaged without slipping, and when the detected vehicle speed Vcar is equal to or higher than a predetermined value (second limit value VLMT2), it is determined according to the detected remaining charge SOC. Clutch engagement force setting means (ECU) for setting the clutch 10 to a value that is engaged when the clutch 10 is slipping.
20, a step 4, 8) and a clutch control means (actuator 1) for controlling the amount of recovery of electric energy by engaging the clutch 10 with the set engaging force FCL.
6, ECU 20).

According to the control device for a front and rear wheel drive vehicle,
The clutch engagement force setting means detects the engagement force of the clutch during recovery of the electric energy to a value at which the clutch is engaged without slipping when the vehicle speed is less than a predetermined value, and detects the engagement force when the detected vehicle speed is equal to or more than the predetermined value. In accordance with the charged remaining amount, the clutch is set to a value at which the clutch is engaged in a slippery state, and the clutch is engaged by the clutch control means with the clutch engagement force thus set. As described above, when the vehicle speed is less than the predetermined value, that is, when the electric motor rotates in a rotation region where there is no possibility of over-rotation, the clutch is engaged without slipping.
Electric energy can be recovered quickly. Also,
When the vehicle speed is equal to or higher than a predetermined value, the clutch is engaged in a slipping state according to the remaining charge, so that the rotation range of the electric motor can be set narrower, so that the electric energy can be reduced while using a relatively small electric motor. And the power storage device can be downsized. Further, when the vehicle speed is equal to or higher than the predetermined value, the clutch engagement force is set according to the remaining charge, so that the amount of collected electric energy can be appropriately obtained according to the remaining charge. As described above, while using a relatively small electric motor and power storage device, electrical energy is always collected regardless of the vehicle speed,
The remaining charge amount of the power storage device can be maintained at an appropriate amount, whereby the driving force of the vehicle can be appropriately secured.

According to a second aspect of the present invention, in the control device 1 for the front and rear wheel drive vehicle 2 according to the first aspect, the electric motor 4
Rotation speed detecting means (E) for detecting the rotation speed NMOT of the motor
CU20, a motor rotation angle position sensor 21), and the clutch engagement force setting means sets the detected rotation speed NMOT of the electric motor 4 to the remaining charge when the vehicle speed Vcar is equal to or higher than a predetermined value (second limit value VLMT2). The present invention is characterized in that the engaging force FCL of the clutch 10 is set to a target value (target motor speed NMOTCMD) according to the SOC.

According to the control device for a front and rear wheel drive vehicle,
When the rotational speed of the electric motor is detected by the electric motor rotational speed detecting means and the vehicle speed is equal to or higher than a predetermined value by the clutch engagement force setting means, the detected rotational speed of the electric motor becomes a target value corresponding to the remaining charge. Thus, the clutch engagement force is set. Therefore, even when a relatively small electric motor is used, the electric power generation by the motor is continued in a stable state while maintaining the rotation speed of the electric motor during power generation at a value lower than the maximum allowable rotation speed during high-speed traveling. Can be executed.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a control device according to an embodiment of the present invention will be described with reference to the drawings. FIG.
1 shows a schematic configuration of a front and rear wheel drive vehicle (hereinafter referred to as “vehicle”) 2 to which a control device 1 according to the present invention is applied. As shown in FIG. 1, the vehicle 2 has left and right front wheels WFL, WFL.
The FR (one driving wheel) is driven by the engine 3, and the left and right rear wheels WRL, WRR (the other driving wheel) are driven by an electric motor (hereinafter referred to as “motor”) 4.

The engine 3 is mounted horizontally on the front of the vehicle 2 and includes an automatic transmission 5 having a torque converter (not shown), a front differential 6 having a reduction gear (not shown), and left and right front drive shafts. 7, 7 and left and right front wheels WF via constant velocity joints 8, 8 and the like.
L, WFR.

The motor 4 is composed of a servomotor, is connected to a battery 9 as a driving source thereof via a PDU 15 described later, and has a clutch 10, an intermediate drive shaft 11, and a reduction gear (not shown). Left and right rear wheels WR via a rear differential 12, left and right rear drive shafts 13, 13 and left and right constant velocity joints 14, 14, and the like.
L, WRR. When the motor 4 is driven by the battery 9 and the clutch 10 is engaged, the rear wheels WRL, WRR are driven, and at this time, the vehicle 2 enters the four-wheel drive state. The motor 4 can be continuously operated at a rotational speed equal to or less than a predetermined maximum allowable rotational speed NMOTMT, and its output is a maximum output (for example, 12 k
W) It can be arbitrarily changed within the following range.

The motor 4 generates power (ie, regenerates) when it is driven to rotate by the traveling energy of the vehicle 2.
And the generated electric energy is supplied to the battery 9 via the PDU 15.
(Power storage device). The remaining charge SOC of the battery 9 is calculated by an ECU 20 described later based on the detected current and voltage values of the battery 9.

Further, the motor 4 is connected to the ECU 20 via the PDU 15, and as described later, when power generation is performed by the motor 4, the rotation speed NMOT of the motor 4 is controlled by the ECU 20. This PDU1
Reference numeral 5 denotes an electric circuit including an inverter and the like. The motor 4 is provided with a motor rotation angle position sensor 21 composed of a resolver. The motor rotation angle position sensor 21 (motor rotation number detecting means) outputs a detection signal corresponding to the rotation angle position of the motor 4. Output to ECU20. Based on this detection signal, the ECU 20 calculates the motor speed NMOT.

The clutch 10 is constituted by a wet multi-plate clutch in which a number of clutch disks 10a (only one is shown) and a number of clutch plates 10b (only one is shown) are alternately arranged in a comb shape. . These clutch disks 10a are connected to the rotating shaft 4a of the motor 4,
The clutch plate 10b is connected to the intermediate drive shaft 11.

The clutch 10 is provided with an actuator 16 (clutch control means). The actuator 16 includes a linear solenoid valve electrically connected to the ECU 20 via a drive circuit 18, a coil spring (both not shown), and the like. The linear solenoid valve has a hydraulic supply mechanism 3
0 is connected.

The hydraulic supply mechanism 30 includes an oil pump 3
1 and an accumulator 32. This oil pump 31 is connected to the drive shaft 13,
The boosted hydraulic pressure is supplied to the accumulator 32 as the drive shaft 13 rotates. The accumulator 32 stores the hydraulic pressure raised by the oil pump 31 and supplies the stored hydraulic pressure to the linear solenoid valve.

The actuator 16 includes an ECU 20
When the linear solenoid valve is being driven by the drive signal from the motor, the clutch disk 10a is pressed against the clutch plate 10b by the oil pressure supplied from the accumulator 32 while the urging force of the coil spring is pressed, and the clutch 10 is engaged. . The engagement force of the clutch 10 is controlled by controlling the duty ratio of the drive signal to the linear solenoid valve, and can be changed continuously. On the other hand, when the linear solenoid valve is not driven, the supply of the hydraulic pressure from the accumulator 32 is stopped, the clutch disc 10a and the clutch plate 10b are disconnected by the urging force of the coil spring, and the clutch 10 is disconnected. .

On the other hand, the left and right front wheels WFL, WFR and the rear wheels WRL, WRR are provided with magnetic pickup type wheel speed sensors 22 (vehicle speed detecting means), respectively. Left and right front wheel rotation speeds N_FL, N_FR and left and right rear wheel rotation speeds N_R
The detection signal (pulse signal) representing L, N_RR is supplied to the ECU
20 respectively. The ECU 20 calculates the vehicle speed Vcar and the rotation speed of the intermediate drive shaft 11 (hereinafter referred to as “drive shaft rotation speed”) NDRV based on these detection signals. The ECU 20 includes an accelerator opening sensor 23.
, A detection signal indicating an opening degree including ON / OFF of the accelerator pedal 17 is input.

The ECU 20 (charge remaining amount detection means, vehicle speed detection means, clutch engagement force setting means, clutch control means, motor speed detection means) includes RAM, ROM, CP
It is composed of a microcomputer (both not shown) comprising a U and an I / O interface.
The ECU 20 drives the actuator 16 based on the detection signals from the various sensors 21 to 23 to drive the actuator 16 to engage / disengage the clutch 10 and the engaging force F thereof, as described later.
The power generation by the motor 4 is controlled by controlling the CL and controlling the motor rotation speed NMOT and the regenerative torque TRQ_MOT.

Hereinafter, control processing for generating electric power by the motor 4 will be described with reference to the flowchart of FIG. This process is performed under the condition that the accelerator pedal 17 is turned off except when the vehicle is traveling uphill, and the clutch 10 is used to generate electric power by the motor 4.
And controls the motor rotation speed NMOT and the like. This processing is performed for a predetermined time (for example, 10 msec).
It is executed every c). In this process, as described below, the motor speed synchronization control and the low speed clutch control process of steps 2 to 4 are executed during low speed traveling, and when the engagement condition of the clutch 10 is satisfied during high speed traveling, step 7 is executed. To 9 are executed.

First, in step 1 (shown as "S1"; the same applies hereinafter), the vehicle speed Vcar is reduced to a first limit value VLM.
It is determined whether it is T1 or less. The first limit value VLMT1 is an upper limit value of the vehicle speed Vcar. Even if the clutch 10 is engaged in a state where there is no slip with the maximum engagement force, that is, in a directly connected state, the motor 4 is allowed to operate at the maximum allowable rotational speed NMOTLMT.
(For example, 65 km / h). When this determination result is YES, that is, the vehicle speed Vca
When r is within the range in which the clutch 10 can be directly connected, the process proceeds to step 2 and executes motor speed synchronization control for synchronizing (matching) the motor speed NMOT with the drive shaft speed NDRV. Although a specific description of this processing is omitted, the motor shaft speed NM is set as the drive shaft speed NDRV as a target value.
OT PID feedback control is performed.

Next, the routine proceeds to step 3, where the motor speed N
Rotational deviation ENMOT between MOT and drive shaft rotation speed NDRV
Is calculated, and the absolute value | ENMOT | of the rotation deviation ENMOT is set to a predetermined value ENLMT (for example, 500 rpm).
m) Determine whether or not: This rotational deviation ENM
OT is the rotation difference between the motor 4 and the intermediate drive shaft 11, that is, the clutch disc 10a and the clutch plate 10
The rotation difference from b is shown. If the result of this determination is NO, that is, the clutch disk 10a and the clutch plate 1
When the rotation difference from 0b is large, it is determined that the clutch 10 is in a state where the clutch 10 cannot be engaged, and the present process is terminated as it is.

On the other hand, if the decision result in the step 3 is YES, that is, if the rotation difference between the clutch disk 10a and the clutch plate 10b is small, the clutch
Assuming that the disk 10a and the clutch plate 10b have been synchronized, the process proceeds to step 4, and the linear solenoid valve of the actuator 16 is driven to release the clutch 1
0 is directly connected with the maximum fastening force, and the process ends. By performing the control of the regenerative torque TRQ_MOT of the motor 4 in addition to the above-described low-speed clutch control processing, power generation is performed by the motor 4 during low-speed traveling.

On the other hand, if the decision result in the step 1 is NO, that is, if Vcar> VLMT1, the routine proceeds to a step 5, where the vehicle speed Vcar is reduced to the second limit value VLMT2.
It is determined whether or not this is the case. This second limit value VL
MT2 (predetermined value) is a value obtained by adding predetermined hysteresis to the first limit value VLMT1 (for example, 70 km /
h), and by using such values, the vehicle speed V
Hunting of control due to the fluctuation of car is prevented. If the result of this determination is NO, it is determined that the vehicle speed Vcar is in a range in which the clutch 10 can be directly connected, and this processing is ended as it is.

On the other hand, if the decision result in the step 5 is YES, that is, if Vcar ≧ VLMT2, the process proceeds to a step 6, in which whether or not the remaining charge SOC of the battery 9 is equal to or less than a predetermined decision value SOC1 (for example, 95%). Is determined. When the result of this determination is NO, it is determined that the battery 9 is in a state where charging is unnecessary, and this process is terminated. On the other hand, when the result of determination is YES, the battery 9 is in a state to be charged and the clutch 10 Is satisfied, the high-speed clutch control process of the following steps 7 to 9 is executed.

That is, the target motor speed NMOTCMD is calculated based on the state of charge SOC (step 7),
The clutch engagement force FCL is calculated from the target motor rotation speed NMOTCMD (step 8), and the duty ratio IOUT of the drive signal output to the linear solenoid valve of the actuator 16 is calculated from the clutch engagement force FCL.
1 is calculated (step 9). Then, a drive signal based on the duty ratio IOUT1 is transmitted to the actuator 16
, The clutch 10 is engaged in a slip state according to the clutch engagement force FCL, and the process is terminated.

Next, the high-speed clutch control of steps 7 to 9 and the high-speed regenerative torque control of the motor 4 will be described in detail with reference to the block diagram shown in FIG.
First, the high-speed clutch control process will be described.
First, based on the state of charge SOC, the SO shown in FIG.
The target motor rotation speed NMOTCMD (target value) is calculated by searching the C-NMOTCMD table.
As shown in the figure, in this table, the target motor speed NMOTCMD is set to be linear so that the smaller the remaining charge SOC, the larger the value. Specifically, the target motor rotational speed NMOTCMD is equal to the remaining charge amount SO.
When C is a value of 0, a predetermined maximum rotational speed NMOT1 is set, and the remaining charge SOC becomes equal to the determination value SO.
In the range of C1 or more, the value is set to 0 because charging is not necessary. As a result, the smaller the remaining charge SOC, the higher the power generation speed of the motor 4 can be, and the more quickly the battery 9 can be charged. Further, the maximum rotation speed NMOT1 is set to a value slightly smaller than the maximum allowable rotation speed NMOTMT in order to prevent the motor 4 from over-rotating.

Next, after calculating the motor rotation speed NMOT based on the detection signal of the motor rotation angle position sensor 21,
Target motor speed NMOTCMD and motor speed NMO
By multiplying the deviation from T by the P term gain, the P term P
Calculate NMOT.

Next, the target motor speed NMOTCMD
The sum of the P term PNMOT and the target motor speed NMOTC
After calculating as the MD correction value NMOTCMDX, based on the correction value NMOTCMDX, an example of N shown in FIG.
By searching the MOTCMD-FCL table,
The clutch engagement force FCL is calculated. As shown in the figure,
In this table, the clutch engagement force FCL is set to a larger value as the target motor speed NMOTCMD is larger. This is because, as described above, the smaller the remaining charge SOC is, the more quickly the battery 9 is charged. In addition, a plurality of tables are set according to the vehicle speed Vcar. In these tables, the clutch engagement force FCL is smaller for the higher vehicle speed Vcar with respect to the same target motor speed NMOTCMD. Is set to a value. For example, the table value of the clutch engagement force FCL shown by the solid line in FIG. 4 is for Vcar = VLMT2, and the table value shown by the broken line is Vcar = V
This is for LMT3 (> VLMT2). When the vehicle speed Vcar is between VLMT2 and VLMT3, the clutch engagement force FCL is calculated by interpolation.

Next, the duty ratio IOUT1 of the drive signal for the linear solenoid valve of the actuator 16 is calculated from the calculated clutch engagement force FCL, and a drive signal based on the duty ratio is output to the linear solenoid valve. 16 through the clutch engagement force FCL. As a result, the clutch 10 is engaged in a slip state according to the clutch engagement force FCL, whereby the rotational force of the intermediate drive shaft 11 is reduced.
0 to the motor 4 at a predetermined rate. At this time, as described above, the target motor speed NMOTCMD
Is set to a value smaller than the maximum allowable rotation speed NMTLMT, the motor 4
, And is driven at a lower rotation speed. With the above control, the motor 4 is controlled to rotate at its rotational speed NMO.
Control is performed so that T converges to the target motor speed NMOTCMD. As a result, power generation by the motor 4 is performed.

Next, the high-speed regenerative torque control will be described. In this control, the amount of power generated by the motor 4, that is, the amount of recovery of electric energy is controlled by controlling the regenerative torque TRQ_MOT of the motor 4 based on the motor speed NMOT.

First, a regenerative torque TRQ_MOT (negative value) of the motor 4 is calculated by searching a table shown in FIG. 6 based on the motor speed NMOT. As shown in the figure, the absolute value of the regenerative torque TRQ_MOT |
TRQ_MOT | indicates that the motor rotation speed NMOT is a predetermined value N
In a range from MOT2 to a predetermined value NMOT3 that is larger than MOT2, the value is set to a smaller value as the motor rotation speed NMOT is larger. This is the motor speed NMOT
Is higher, the electric energy per unit time generated by the motor 4 increases. Also, the absolute value | TR
Q_MOT | is equal to or less than a predetermined value TR when the value is less than a predetermined value NMOT2.
It is set to Q1, and is set to the value 0 in a range larger than the predetermined value NMOT3. The table shown in FIG. 7 is for when the motor 4 is operated at the maximum output. The predetermined value NMOT3 is set to a value smaller than the maximum allowable rotation speed NMOTLM in order to prevent the motor 4 from over-rotating. ing.

Next, current feedback proportional control is performed in which a value obtained by converting the regenerative torque TRQ_MOT into a current value is set as a target value, and an actual command value IOUT2 to the motor 4 is set as a feedback value. That is, the regenerative torque TRQ_MO
A deviation DI between T and the command value IOUT2 is calculated, and a command value IOUT2 to the motor 4 is calculated by multiplying the deviation DI by a P-term gain. And this command value IO
Electric power is generated in a state in which the motor 4 is controlled by a control signal based on the UT 2, so that the battery 9 is charged with electric energy with a corresponding recovery amount.

As described above, according to the control device 1 of the present embodiment, when the vehicle speed Vcar is equal to or higher than the second limit value, that is, when the vehicle is traveling at high speed and the remaining charge SOC of the battery 9 is small, the control is accordingly performed. The clutch 10 is engaged with the calculated clutch engagement force FCL to control the motor rotation speed NMOT, and the regenerative torque TRQ_MOT of the motor 4 is controlled based on the motor rotation speed NMOT, so that the power generation amount of the motor 4, The amount of energy recovery is controlled. On the other hand, when the vehicle speed Vcar is equal to or less than the first limit value, that is, while the vehicle is traveling at a low speed, the remaining charge SO of the battery 9 is
When C is small, the clutch 10 is engaged with the maximum engagement force. Therefore, while using a relatively small motor 4, electric energy can be recovered regardless of the vehicle speed Vcar, and the capacity of the battery 9 can be reduced with the downsizing of the motor 4. Further, for the above-described reason, during high-speed running, the remaining charge amount SO of the battery 9 is determined.
C, that is, electrical energy can be recovered without excess or deficiency according to the degree of need for charging, and the remaining charge SOC of the battery 9 can be appropriately controlled. Thereby, the driving force of the vehicle 2 can be secured while minimizing the decrease in the running energy during the recovery of the electric energy during the high-speed running. As described above, while using the relatively small motor 4 and the battery 9, the electric energy can always be collected regardless of the vehicle speed Vcar, and the remaining charge SOC of the battery 9 can be maintained at an appropriate level. 2 can be appropriately secured. In addition, during high-speed running, the engaging force FCL of the clutch 10 is controlled such that the rotational speed NMOT of the motor 4 becomes the target motor rotational speed NMOTCMD smaller than the maximum allowable rotational speed NMOTMT. While using, the power generation operation can be continuously executed in a stable state during high-speed traveling.

In the present invention, the front wheel W
The FL and WFR are not limited to the front and rear wheel drive vehicle of the embodiment in which the rear wheels WRL and WRR are driven by the motor 4, respectively.
The reverse configuration is adopted, that is, the rear wheels WRL, WRR and the front wheels WFL, WF are driven by the engine 3 and the motor 4.
The invention may be applied to front and rear wheel drive vehicles that respectively drive R. Further, the clutch 10 for connecting and disconnecting between the motor 4 and the rear wheels WRL, WRR is not limited to the wet multi-plate clutch type of the embodiment, but may be any clutch capable of controlling the transmission capacity. A clutch or an electromagnetic clutch may be employed. In addition, as a condition for generating electric power by the motor 4 during high-speed traveling, the vehicle speed Vcar
Other appropriate conditions may be added to the remaining charge SOC. For example, the fact that the steering angle of the steering is equal to or smaller than a predetermined angle may be added to the execution condition, whereby the running stability can be improved. Further, the configuration for storing the electric energy generated by the motor 4 is not limited to the battery 9 of the embodiment, but may be any configuration that can store electric energy such as a capacitor.

The method of controlling the clutch 10 in order to perform regeneration by the motor 4 during high-speed running is not limited to that of the embodiment, and the remaining charge SOC, the driving state of the vehicle, the execution time of regeneration, and the like are used as parameters. Other control methods may be used to perform optimal regeneration. For example, the following techniques may be employed.

During high-speed running, the regenerative torque TRQ_MOT of the motor 4 is set according to the remaining charge SOC, and the target motor speed NMO is set according to the regenerative torque TRQ_MOT.
The TCMD is set, and the engagement force FCL of the clutch 10 is controlled so that the motor speed NMOT becomes equal to the target motor speed NMOTCMD. At the time of high-speed running, it is determined whether or not the regeneration by the motor 4 is performed according to the remaining charge SOC, and when it is determined that the regeneration is performed, the target motor rotation speed NMOTCMD is set to a constant value (for example, NMOT1), and The regenerative torque TRQ_MOT of the motor 4 is set according to the operating state (for example, a decelerating running state such as a vehicle speed or an accelerator off state), and the motor speed NMOT is set to the target motor speed NMOTCMD.
Thus, the engagement force FCL of the clutch 10 is controlled. At the time of high-speed running, it is determined whether or not the regeneration by the motor 4 is performed according to the remaining charge SOC. When it is determined that the regeneration is performed, the regeneration torque TRQ_MOT of the motor 4 is set to a constant value (for example, TRQ1). And the target motor speed N
The MOTCMD is set according to the driving state (for example, a decelerating running state such as a vehicle speed or an accelerator off state), and the engagement force FCL of the clutch 10 is controlled so that the motor rotation speed NMOT becomes the target motor rotation speed NMOTCMD.

[0040]

As described above, according to the present invention, electric energy is always recovered regardless of the vehicle speed while using a relatively small electric motor and a power storage device, and the remaining charge amount of the power storage device is maintained at an appropriate level. Therefore, the driving force of the vehicle can be appropriately secured. In addition, even when a relatively small electric motor is used, during high-speed running, the electric power generation by the motor is continued in a stable state while maintaining the rotation speed of the electric motor during power generation at a value lower than the maximum allowable rotation speed. Can be executed.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a front and rear wheel drive vehicle to which a control device according to an embodiment of the present invention is applied.

FIG. 2 is a flowchart showing a power generation control process of the electric motor by the control device.

FIG. 3 is a block diagram illustrating a schematic configuration of power generation control during high-speed running by a control device.

FIG. 4 is a diagram showing an example of an SOC-NMOTCMD table used for calculating a target motor rotation speed NMOTCMD.

FIG. 5: NMOT used for calculating clutch engagement force FCL
It is a figure showing an example of a CMD-FCL table.

FIG. 6 shows an NM used for calculating a regenerative torque TRQ_MOT.
It is a figure showing an example of an OT-TRQ_MOT table.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 control device 2 front and rear wheel drive vehicle 3 engine 4 electric motor 9 battery (power storage device) 10 clutch 16 actuator (clutch control unit) 20 ECU (remaining charge detection unit, vehicle speed detection unit, clutch engagement force setting unit, clutch control unit , Motor rotation speed detection means) 21 motor rotation angle position sensor (motor rotation speed detection means) 22 wheel rotation speed sensor (vehicle speed detection means) Vcar vehicle speed VLMT2 second limit value (predetermined value) SOC remaining charge FCL clutch engagement force NMOT Electric motor rotation speed NMOTCMD Target motor rotation speed (target value) WFL, WFR Left and right front wheels (one driving wheel) WRL, WRR Left and right rear wheels (the other driving wheel)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) B60K 41/00 301 B60K 41/00 301B 5H115 301C 41/02 41/02 B60L 7/14 B60L 7/14 H02J 7/00 P H02J 7/00 X B60K 9/00 E (72) Inventor Yasuhiko Suai 1-4-1 Chuo, Wako-shi, Saitama F-term in Honda R & D Co., Ltd. 3D036 GA11 GA16 GB05 GD02 GD09 GE02 GF10 GG34 GG35 GG57 GH13 GH26 GJ20 3D039 AB27 AC03 3D041 AA09 AB01 AC01 AC06 AC10 AD02 AD22 AD23 AE02 AE03 AE20 AE22 AF01 3D043 AB16 EA02 EA05 EA18 EA45 EB07 EB12 EF02 A07 EA02 EF02 EF12 AE05 QI04 QI18 QN06 SE03 SE06 SE08 TB03 TI02

Claims (2)

[Claims] An electric motor is used to drive one of the front and rear driving wheels by an engine, and the other is driven by an electric motor, so that traveling energy can be recovered as electric energy for driving the electric motor by power generation of the electric motor. Composed,
A control device for a front and rear wheel drive vehicle that charges the collected electric energy to a power storage device, wherein the other drive wheel and the electric motor are fastened and disconnected, and the fastening force is variably configured. A clutch, a charge remaining amount detecting means for detecting a charge remaining amount of the power storage device, a vehicle speed detecting means for detecting a vehicle speed of the front and rear wheel drive vehicle, and a coupling force of the clutch during recovery of the electric energy, When the detected vehicle speed is less than a predetermined value, the clutch is set to a value that can be engaged without slipping,
When the detected vehicle speed is equal to or higher than the predetermined value, a clutch engagement force setting unit that sets the clutch to a value that is engaged in a state in which the clutch is slipping, according to the detected remaining charge, A control device for a front-rear wheel drive vehicle, comprising: clutch control means for controlling the amount of recovery of the electric energy by engaging the clutch with an engagement force. 2. The electric motor according to claim 1, further comprising: a motor rotation speed detecting unit configured to detect a rotation speed of the electric motor, wherein the clutch engagement force setting unit detects the detected rotation speed of the electric motor when the vehicle speed is equal to or higher than the predetermined value. The control device for a front-rear wheel drive vehicle according to claim 1, wherein the engagement force of the clutch is set such that the number becomes a target value corresponding to the remaining charge amount.