JP7450858B2 - vehicle drive system - Google Patents

Description

The present invention relates to a vehicle drive system, and particularly to a vehicle drive system equipped with a vehicle attitude control function.

Japanese Unexamined Patent Publication No. 2017-89465 (Patent Document 1) describes a vehicle drive system. In this vehicle drive system, additional deceleration is determined according to the steering speed, and the final target torque to be generated by the prime mover of the vehicle is reduced so that this additional deceleration is achieved. In this way, by applying additional deceleration, the attitude of the vehicle during cornering is controlled. Furthermore, by controlling the attitude of the vehicle, the load applied to the front wheels, which are steered wheels, increases, and the cornering force of the front wheels increases. This improves the ability of the vehicle to turn at the beginning of entering a curve, and improves the responsiveness to a steering operation, so that the vehicle behaves as intended by the driver.

Furthermore, the behavior of the vehicle in response to a steering operation during cornering also changes depending on the amount of depression of the accelerator pedal. For this reason, in the vehicle drive system described in Patent Document 1, a correction coefficient having a different value depending on the amount of depression of the accelerator pedal is set. By multiplying the additional deceleration by this correction coefficient, the set additional deceleration is corrected and more natural and stable cornering operations are realized.

Furthermore, Japanese Patent Application Publication No. 2019-217992 (Patent Document 2) describes a vehicle control system and method. In this vehicle control system, in a rear wheel drive vehicle, additional acceleration is determined according to the steering speed, and the final target torque to be generated by the prime mover of the vehicle is increased so that this additional acceleration is achieved. In this way, in rear-wheel drive vehicles, the additional acceleration is set based on the steering speed and the final target torque is increased to control the vehicle attitude, improve the turning ability of the vehicle, and increase the steering angle. It is known that responsiveness to operations can be improved.

JP2017-89465A JP2019-217992A

However, the driving force applied to the wheels of the vehicle is not always the same even if the amount of operation of the accelerator pedal is the same. For example, in the case of a vehicle where the driving force of the engine is transmitted to the wheels via the transmission, even if the amount of operation of the accelerator pedal is the same, the driving torque applied to the wheels depends on the gear position set in the transmission. will be different. On the other hand, in the vehicle drive system described in Patent Document 1, the additional deceleration is corrected using a correction coefficient whose value changes depending on the amount of operation of the accelerator pedal. Therefore, in the vehicle drive system described in Patent Document 1, even when the vehicle is running with the same drive torque and the same steering, different additional decelerations are set depending on the amount of operation of the accelerator pedal. Become. The inventor of the present invention discovered a technology in which, in the vehicle drive system described in Patent Document 1, different vehicle posture control is performed depending on the amount of operation of the accelerator pedal even if the vehicle is in the same running state, which may give a sense of discomfort to the driver. I found a problem.

Therefore, the present invention provides a vehicle drive system that can avoid different vehicle posture controls being executed for the same vehicle driving state depending on the amount of operation of the accelerator pedal, and can suppress the sense of discomfort given to the driver. is intended to provide.

In order to solve the above-mentioned problems, the present invention provides a vehicle drive system equipped with a vehicle attitude control function, which includes a prime mover that generates a driving force that drives the front wheels of a vehicle, an automatic transmission, and a vehicle that steers the vehicle. a steering device for detecting the steering device, a steering angle sensor for detecting the steering angle by the steering device, an accelerator opening sensor for detecting the amount of operation of the accelerator pedal by the driver, and an accelerator opening sensor for detecting the amount of operation of the accelerator pedal by the driver. The controller includes a controller that sets a target acceleration based on an operation amount, and a vehicle state detection section that detects a relationship between an accelerator pedal operation amount detected by an accelerator opening sensor and the set target acceleration. sets the deceleration torque based on the steering speed detected by the steering angle sensor and the operation amount of the accelerator pedal detected by the accelerator opening sensor, and based on this deceleration torque, the basic target torque corresponding to the target acceleration is set. The vehicle state detection section detects the relationship between the accelerator pedal operation amount and the set target acceleration by detecting the gear position of the automatic transmission, and performs control. The device is characterized in that when the target acceleration relative to the amount of operation of the accelerator pedal detected by the vehicle state detection section is small, the deceleration torque is corrected to a larger value than when the target acceleration relative to the amount of operation of the accelerator pedal is large. It is said that

In the present invention configured in this way, the front wheels of the vehicle are driven by the prime mover, and the steering angle by the steering device is detected by the steering angle sensor. Further, an accelerator opening sensor detects the amount of operation of the accelerator pedal, and a target acceleration is set by the controller based on this. Furthermore, the vehicle state detection unit detects the relationship between the operation amount of the accelerator pedal detected by the accelerator opening sensor and the set target acceleration. The controller sets a deceleration torque based on the steering speed and the amount of operation of the accelerator pedal, and executes vehicle attitude control to modify the basic target torque corresponding to the target acceleration based on this deceleration torque. Further, when the target acceleration relative to the operation amount of the accelerator pedal detected by the vehicle state detection section is small, the controller corrects the deceleration torque to a larger value than when it is large.

The target acceleration set for a certain accelerator pedal operation amount is changed depending on the state of the vehicle. Therefore, even if the amount of operation of the accelerator pedal is the same, the set target accelerations will be different. On the other hand, the controller sets the deceleration torque based on the steering speed and the amount of operation of the accelerator pedal and executes vehicle attitude control, so even if the steering and target acceleration are the same, depending on the amount of operation of the accelerator pedal, There is a possibility that the deceleration torque in vehicle attitude control will be different. According to the present invention configured as described above, when the target acceleration relative to the operation amount of the accelerator pedal is small, the deceleration torque in vehicle attitude control is corrected to a larger value than when the target acceleration is large. Therefore, even if the relationship between the operation amount of the accelerator pedal and the target acceleration changes, substantially the same deceleration torque can be set for the same steering and target acceleration. As a result, it is possible to prevent the vehicle attitude control from varying depending on the amount of operation of the accelerator pedal for the same driving state of the vehicle, and it is possible to prevent the driver from feeling uncomfortable.

The present invention also provides a vehicle drive system equipped with a vehicle attitude control function, which includes: a prime mover that generates a driving force that drives rear wheels of a vehicle; an automatic transmission; a steering device that steers the vehicle; A steering angle sensor detects the steering angle of the steering device, an accelerator opening sensor detects the amount of operation of the accelerator pedal by the driver, and a target is set based on the amount of operation of the accelerator pedal detected by the accelerator opening sensor. It has a controller that sets the acceleration, and a vehicle state detection unit that detects the relationship between the accelerator pedal operation amount detected by the accelerator opening sensor and the set target acceleration, and the controller Vehicle attitude control that sets acceleration torque based on the detected steering speed and the amount of operation of the accelerator pedal detected by the accelerator opening sensor, and corrects the basic target torque corresponding to the target acceleration based on this acceleration torque. The vehicle state detection section detects the relationship between the operation amount of the accelerator pedal and the set target acceleration by detecting the gear position of the automatic transmission, and the controller detects the vehicle state detection section. When the target acceleration relative to the amount of operation of the accelerator pedal detected by the section is small, the acceleration torque is corrected to a larger value than when the target acceleration relative to the amount of operation of the accelerator pedal is large.

In a vehicle where the rear wheels are driven by a prime mover, the acceleration torque is set based on the steering speed and the amount of operation of the accelerator pedal, and the basic target torque corresponding to the target acceleration is corrected based on this acceleration torque. It is known that vehicle attitude control can be achieved. According to the present invention configured as described above, when the target acceleration relative to the operation amount of the accelerator pedal is small, the acceleration torque in vehicle attitude control is corrected to a larger value than when the target acceleration is large. Therefore, even if the relationship between the operation amount of the accelerator pedal and the target acceleration changes, substantially the same acceleration torque can be set for the same steering and target acceleration. As a result, it is possible to prevent the vehicle attitude control from varying depending on the operation amount of the accelerator pedal for the same driving state of the vehicle, and it is possible to prevent the driver from feeling uncomfortable.

In the present invention, the vehicle state detection section is preferably configured to detect the amount of operation of the accelerator pedal required to maintain the same vehicle speed.

According to the present invention configured in this manner, the operation amount of the accelerator pedal required to maintain the same vehicle speed can be changed, and the operability of the vehicle can be improved. Further, according to the present invention, even if the amount of operation of the accelerator pedal to obtain the same acceleration is changed, the same vehicle attitude control is executed, and it is possible to prevent the driver from feeling uncomfortable.

Preferably, the present invention further includes an automatic transmission, and the vehicle state detection unit detects the relationship between the operation amount of the accelerator pedal and the set target acceleration by detecting the gear position of the automatic transmission. .

When the driving force generated by the prime mover is transmitted to the wheels via an automatic transmission, the amount of accelerator pedal operation required to obtain the same target acceleration varies depending on the automatic transmission gear setting. becomes. In the present invention configured as described above, the gear stage of the automatic transmission is detected by the vehicle state detection section. According to the present invention configured as described above, even if the gear position of the automatic transmission is changed and the relationship between the operation amount of the accelerator pedal and the target acceleration is changed, it is possible to perform similar vehicle attitude control. This can prevent the driver from feeling uncomfortable.

In the present invention, preferably, the prime mover is a rotating electrical machine, and the vehicle state detection section detects the generated torque of the rotating electrical machine and the regenerative torque of the rotating electrical machine with respect to the operation amount of the accelerator pedal. Detects the relationship between the manipulated variable and the set target acceleration.

In a vehicle equipped with a rotating electric machine as a prime mover, operability can be improved by making it possible to change the torque generated and the regenerated kinetic energy for a given accelerator pedal operation amount. According to the present invention configured as described above, the vehicle state detection section detects the generated torque of the rotating electrical machine and the regenerative torque of the rotating electrical machine with respect to the operation amount of the accelerator pedal. As a result, although the relationship between the operation amount of the accelerator pedal and the target acceleration is changed, the same vehicle attitude control can be executed, and it is possible to prevent the driver from feeling uncomfortable.

According to the vehicle drive system of the present invention, it is possible to avoid executing different vehicle attitude control for the same vehicle driving state depending on the operation amount of the accelerator pedal, and it is possible to avoid causing a sense of discomfort to the driver. can be suppressed.

1 is a block diagram showing the overall configuration of a vehicle equipped with a vehicle drive system according to a first embodiment of the present invention. FIG. 1 is a block diagram showing the electrical configuration of a vehicle drive system according to a first embodiment of the present invention. 3 is a flowchart of engine control processing in which the vehicle drive system controls the engine according to the first embodiment of the present invention. 2 is a flowchart of a deceleration torque determination process in which the vehicle drive system determines a deceleration torque according to the first embodiment of the present invention. 2 is a flowchart of additional deceleration correction processing in which the vehicle drive system corrects additional deceleration according to the first embodiment of the present invention. It is a map showing the relationship between the target additional deceleration and steering speed determined by the vehicle drive system according to the first embodiment of the present invention. 3 is a map showing the relationship between the additional deceleration correction coefficient determined by the vehicle drive system according to the first embodiment of the present invention and the vehicle speed. 3 is a map showing a relationship between a steering angle and a correction coefficient for additional deceleration determined by the vehicle drive system according to the first embodiment of the present invention. It is a map showing the relationship between the correction coefficient of additional deceleration determined by the vehicle drive system according to the first embodiment of the present invention and the accelerator opening degree. 3 is a map showing a relationship between a correction coefficient for additional deceleration determined by the vehicle drive system according to the first embodiment of the present invention and required deceleration. 5 is a time chart showing changes in parameters related to engine control by the vehicle drive system when a vehicle equipped with the vehicle drive system according to the first embodiment of the present invention makes a turn; FIG. 2 is a block diagram showing the overall configuration of a vehicle equipped with a vehicle drive system according to a second embodiment of the present invention. In the vehicle drive system according to the second embodiment of the present invention, it is a torque control map showing the relationship between the accelerator pedal opening and the output torque and regenerative torque of the rotating electric machine.

Next, a vehicle drive system according to an embodiment of the present invention will be described with reference to the accompanying drawings.

First, with reference to FIG. 1, a vehicle equipped with a vehicle drive system according to a first embodiment of the present invention will be described. FIG. 1 is a block diagram showing the overall configuration of a vehicle equipped with a vehicle drive system according to a first embodiment of the present invention.

In FIG. 1, reference numeral 1 indicates a vehicle equipped with a vehicle drive system according to this embodiment. An engine 4, which is a prime mover that drives drive wheels (left and right front wheels 2 in the example of FIG. 1), is mounted on the front of the vehicle 1. The driving force generated by the engine 4 is transmitted to the front wheels 2 via the automatic transmission 5. The engine 4 is an internal combustion engine such as a gasoline engine or a diesel engine.

The vehicle 1 also includes a steering device 6 for steering the front wheels 2, which are steered wheels, a steering wheel 6a for operating the steering device 6, and a steering angle sensor 8 for detecting the rotation angle of the steering wheel 6a. have Furthermore, the vehicle 1 includes an accelerator opening sensor 10a that detects the operation amount (accelerator opening) of the accelerator pedal 10, a vehicle speed sensor 12 that detects vehicle speed, and a brake fluid pressure sensor 14 that detects brake fluid pressure. Each of these sensors outputs each detected value to a PCM (Power-train Control Module) 16, which is a controller.

Further, the steering wheel 6a is provided with paddle switches 6b, which are two gear shift operation parts, and when the automatic transmission 5 is set to manual mode, by operating these paddle switches 6b, The gear stage of the automatic transmission 5 can be switched to a low speed side or a high speed side. Further, the automatic transmission 5 is provided with a transmission sensor 5a which is a vehicle state detection section, and thereby the gear position of the automatic transmission 5 is detected. These engine 4, automatic transmission 5, transmission sensor 5a, steering device 6, steering angle sensor 8, accelerator opening sensor 10a, and PCM 16 constitute a vehicle drive system according to the first embodiment of the present invention.

Next, with reference to FIG. 2, the electrical configuration of the vehicle drive system according to the first embodiment of the present invention will be described. FIG. 2 is a block diagram showing the electrical configuration of the vehicle drive system according to the first embodiment of the present invention.
In this embodiment, the PCM 16 detects the engine based on the detection signals output from various sensors that detect the operating state of the engine 4, in addition to the detection signals from the steering angle sensor 8, accelerator opening sensor 10a, and vehicle speed sensor 12 described above. 4 (for example, a throttle valve, a turbo supercharger, a variable valve mechanism, an ignition device, a fuel injection valve, an EGR device, etc.). Further, the PCM 16 outputs a control signal to the automatic transmission 5 to set an appropriate gear based on the vehicle speed of the vehicle 1, the rotation speed of the engine 4, etc. Furthermore, when the automatic transmission 5 is set to manual mode, the automatic transmission 5 is automatically shifted to switch the gear stage to a low speed side or a high speed side based on the operation of the paddle switch 6b by the driver. A control signal is output to machine 5.

Furthermore, detection signals from the steering angle sensor 8, accelerator opening sensor 10a, vehicle speed sensor 12, brake fluid pressure sensor 14, and transmission sensor 5a are input to the PCM 16, and the PCM 16 operates based on these detection signals. Executes vehicle attitude control. In this embodiment, a transmission sensor 5a is provided as a vehicle state detection section that detects the gear position of the automatic transmission 5. Note that the amount of operation of the accelerator pedal required to maintain the same vehicle speed changes depending on the gear position set in the automatic transmission 5, and the transmission sensor 5a detects this. Here, since the gear position of the automatic transmission 5 is switched based on the control signal from the PCM 16, information on the gear position of the automatic transmission 5 can also be obtained from inside the PCM 16. Therefore, the PCM 16 can also function as a vehicle state detection section.

The PCM 16 includes a basic target torque determination section 18 , a deceleration torque determination section 20 , a final target torque determination section 22 , and an engine control section 24 .
The basic target torque determining unit 18 is configured to set a target acceleration based on the driving state of the vehicle 1 including the operation of the accelerator pedal 10, and to determine a basic target torque corresponding to the target acceleration.

The deceleration torque determination unit 20 determines a deceleration torque for applying deceleration to the vehicle 1 based on a yaw rate related quantity such as a steering speed of the vehicle 1, an operation amount of an accelerator pedal, etc. in vehicle attitude control. It is configured. In this embodiment, the deceleration torque determination unit 20 uses the steering speed of the vehicle 1 as the yaw rate related quantity.
The final target torque determination unit 22 is configured to determine the final target torque based on the basic target torque and the corrected deceleration torque.
The engine control unit 24 is configured to output a control signal to the engine 4 so as to output the final target torque.

Each of these components of the PCM 16 includes a CPU, various programs that are interpreted and executed on the CPU (including basic control programs such as the OS, and application programs that are started on the OS and realize specific functions), and programs. It is composed of a computer equipped with an internal memory such as ROM or RAM for storing various data.

Next, processing performed by the vehicle drive system will be described with reference to FIGS. 3 to 10.
FIG. 3 is a flowchart of an engine control process in which the vehicle drive system according to the first embodiment of the present invention controls the engine 4, and FIG. 4 is a flowchart in which the vehicle drive system according to the first embodiment of the present invention determines the deceleration torque. 5 is a flowchart of a deceleration torque determination process, FIG. 5 is a flowchart of an additional deceleration correction process in which the vehicle drive system according to the first embodiment of the present invention corrects additional deceleration, and FIG. 6 is a flowchart of the additional deceleration correction process according to the first embodiment of the present invention. 7 to 10 are maps showing the relationship between the target additional deceleration determined by the vehicle drive system according to the first embodiment of the present invention and the steering speed, and FIGS. It is a map showing the relationship between the coefficient and each of vehicle speed, steering angle, accelerator opening, and required deceleration.

The engine control process in FIG. 3 is started when the ignition of the vehicle 1 is turned on and power is applied to the vehicle drive system, and is repeatedly executed at predetermined time intervals.
When the engine control process is started, as shown in FIG. 3, in step S1, the PCM 16 acquires various information regarding the driving state of the vehicle 1. Specifically, the PCM 16 detects the steering angle detected by the steering angle sensor 8, the accelerator opening detected by the accelerator opening sensor 10a, the vehicle speed detected by the vehicle speed sensor 12, the brake fluid pressure detected by the brake fluid pressure sensor 14, Detection signals output from the various sensors described above, including the currently set gear stage of the automatic transmission 5 detected by the transmission sensor 5a, are acquired as information regarding the operating state.

Next, in step S2, the basic target torque determination unit 18 of the PCM 16 sets a target acceleration based on the driving state of the vehicle 1 including the operation amount of the accelerator pedal 10 acquired in step S1. Specifically, the basic target torque determining unit 18 determines the current vehicle speed and gear shift from acceleration characteristic maps (prepared in advance and stored in a memory or the like) defined for various vehicle speeds and various gear stages. An acceleration characteristic map corresponding to the stage is selected, and a target acceleration corresponding to the current accelerator opening is determined with reference to the selected acceleration characteristic map.

Next, in step S3, the basic target torque determination unit 18 determines the basic target torque of the engine 4 for realizing the target acceleration determined in step S2. In this case, the basic target torque determination unit 18 determines the basic target torque within the range of torque that the engine 4 can output based on the current vehicle speed, gear position, road surface slope, road surface μ, etc.

Further, in parallel with the processing in steps S2 and S3, in step S4, the deceleration torque determination unit 20 executes a deceleration torque determination process to determine a deceleration torque for applying deceleration to the vehicle 1 based on the steering operation. . That is, in step S4 of FIG. 3, the flowchart shown in FIG. 4 is called as a subroutine for executing a deceleration torque determination process for determining the deceleration torque to be added by vehicle attitude control.

As shown in FIG. 4, when the deceleration torque determination process is started, in step S21, the deceleration torque determination unit 20 determines whether the absolute value of the steering angle acquired in step S1 of FIG. It is determined whether the steering wheel 6a is being turned. As a result, if the absolute value of the steering angle is increasing, the process proceeds to step S22, and the deceleration torque determination unit 20 calculates the steering speed based on the steering angle acquired in step S1.

Next, in step S23, the deceleration torque determination unit 20 determines whether the absolute value of the steering speed is decreasing.
As a result, if the absolute value of the steering speed is not decreasing, that is, if the absolute value of the steering speed is increasing or not changing, the process advances to step S24, and the deceleration torque determining unit 20 , obtain the target additional deceleration based on the steering speed. This target additional deceleration is a deceleration that should be added to the vehicle 1 according to the steering operation as vehicle attitude control in order to accurately realize the vehicle behavior intended by the driver.

Specifically, the deceleration torque determining unit 20 obtains the target additional deceleration corresponding to the steering speed calculated in step S22, based on the relationship between the target additional deceleration and the steering speed shown in the map of FIG.
The horizontal axis in FIG. 6 shows the steering speed, and the vertical axis shows the target additional deceleration. As shown in FIG. 6, when the steering speed is less than or equal to the threshold T _S , the corresponding target additional deceleration is zero. That is, when the steering speed is less than or equal to the threshold T _S , the PCM 16 stops the vehicle attitude control (specifically, the reduction of the output torque of the engine 4) that applies deceleration to the vehicle 1 based on the steering operation.

On the other hand, if the steering speed exceeds the threshold T _S , as the steering speed increases, the target additional deceleration corresponding to this steering speed changes from the minimum value (0.05 m/s ² in FIG. 6) to a predetermined value. increases asymptotically to the upper limit value D _max (for example, 1 m/s ² ). That is, as the steering speed increases, the target additional deceleration increases, and the rate of increase of the amount of increase becomes smaller.

Next, in step S25 of FIG. 4, the deceleration torque determining unit 20 executes additional deceleration correction processing to correct the target additional deceleration acquired in step S24. That is, in step S25, the flowchart shown in FIG. 5 is called as a subroutine for executing the additional deceleration correction process.

As shown in FIG. 5, when the additional deceleration correction process is started, in step S41, the deceleration torque determination unit 20 calculates the vehicle speed, steering angle, accelerator opening, and brake fluid pressure obtained in step S1 of FIG. Based on this, correction coefficients K1 to K4 for correcting the additional deceleration are obtained.
Specifically, the deceleration torque determination unit 20 refers to the maps in FIGS. 7 to 10 that show the relationships between vehicle speed, steering angle, accelerator opening, and required deceleration and correction coefficients K1 to K4, Correction coefficients K1, K2, K3, and K4 corresponding to vehicle speed, steering angle, accelerator opening, and required deceleration are obtained.

FIG. 7 is a map showing the relationship between the additional deceleration correction coefficient K1 determined by the deceleration torque determination unit 20 and the vehicle speed according to the embodiment of the present invention. The horizontal axis in FIG. 7 shows the vehicle speed, and the vertical axis shows the correction coefficient K1. As shown in FIG. 7, in the speed range of 10 km/h to 60 km/h, the correction coefficient K1 is set to become smaller as the vehicle speed decreases, and in the speed range of 80 km/h or more, the vehicle speed increases. Indeed, the correction coefficient K1 is set to be small. In a speed range where the vehicle speed is 60 km/h or more and 80 km/h or less, the correction coefficient K1 is constant at 1, and no correction of additional deceleration is performed. Further, when the vehicle speed is 10 km/h or less, the correction coefficient K1 is constant at 0.1.

FIG. 8 is a map showing the relationship between the additional deceleration correction coefficient K2 determined by the deceleration torque determination unit 20 and the steering angle according to the embodiment of the present invention. In FIG. 8, the horizontal axis indicates the steering angle, and the vertical axis indicates the correction coefficient K2. As shown in FIG. 8, when the steering angle is less than 120 degrees, the correction coefficient K2 is set to become smaller as the steering angle becomes smaller. When the steering angle is 120 degrees or more, the correction coefficient K2 is constant at a maximum value of 1. Further, when the steering angle is 0 degrees, the correction coefficient K2 has a minimum value of 0.3.

FIG. 9 is a map showing the relationship between the additional deceleration correction coefficient K3 determined by the deceleration torque determination unit 20 and the accelerator opening according to the embodiment of the present invention. In FIG. 9, the horizontal axis indicates the accelerator opening, and the vertical axis indicates the correction coefficient K3, which is the accelerator opening gain. As shown in FIG. 9, when the accelerator opening is smaller than about 60%, the correction coefficient K3 is set to become smaller as the accelerator opening becomes larger. When the accelerator opening degree is greater than about 60%, the correction coefficient K3 is constant at a minimum value of 0.25.

Further, as shown in FIG. 9, a different map is set for the correction coefficient K3 for correcting the additional deceleration based on the accelerator opening degree for each gear stage of the automatic transmission 5. In FIG. 9, the solid line indicates a map used when the vehicle 1 is driven with the shifter (not shown) set in the normal drive range (D range). On the other hand, the dashed dotted line in FIG. 9 shows the map used when the left paddle switch 6b of the steering wheel 6a is operated once and the driver requests a downshift (deceleration request). There is. Further, the two-dot chain line in FIG. 9 indicates a map that is used when the driver requests further downshifting and the left paddle switch 6b is operated twice.

On the other hand, the broken line in FIG. 9 indicates a map used when the paddle switch 6b on the right side of the steering wheel 6a is operated once and the driver requests an upshift (acceleration request). Furthermore, the dotted line in FIG. 9 shows the map used when the driver requests further upshifting and the right paddle switch 6b is operated twice. In this way, in this embodiment, different maps with correction coefficients K3 are used depending on the gear position set in the automatic transmission 5, and the accelerator opening degree shown on the horizontal axis in FIG. 9 is the same. Also, a different correction coefficient K3 is set.

As shown by the solid line in FIG. 9, when the shifter (not shown) is set to the normal drive range, the correction coefficient K3 takes a maximum value of 1 in the region where the accelerator opening is about 10% or less. , decreases as the accelerator opening increases, and reaches a minimum value of 0.25 in a region where the accelerator opening is about 60% or more. On the other hand, when the driver has upshifted (switched the automatic transmission 5 to the high speed side), the correction coefficient K3 is determined by the accelerator opening of about 10% or less, as shown by the broken line in FIG. The maximum value in the region is set to about 0.9. Further, the correction coefficient K3 decreases as the accelerator opening increases, and reaches a minimum value of 0.25 in a region where the accelerator opening is about 50% or more. Furthermore, as shown by the dotted line in FIG. 9, when the vehicle is shifted up two steps to the high speed side, the correction coefficient K3 is set to an even smaller value. In this way, even if the accelerator opening degree is the same, the correction coefficient K3 is set to a smaller value as the speed is switched to the higher speed side.

On the other hand, as shown by the dashed line in FIG. 9, when the driver is downshifting, the correction coefficient K3 takes a maximum value of 1 in a region where the accelerator opening is about 10% or less, and In a region of about 20% or more, the value is larger than that when set to the normal drive range. In a region where the accelerator opening is about 65% or more, the correction coefficient K3 has a minimum value of 0.25.
Furthermore, as shown by the two-dot chain line in FIG. 9, when the two-step downshift is performed, the correction coefficient K3 takes a maximum value of 1 in a region where the accelerator opening is about 10% or less, and when the accelerator opening is In the region of about 25% or more, the value is larger than that when the shift is down by one step. In a region where the accelerator opening is about 75% or more, the correction coefficient K3 has a minimum value of 0.25.

In addition, in the region where the accelerator opening is about 10% or less in FIG. 9, the value of the correction coefficient K3 is lowered during upshifts (broken lines and dotted lines in FIG. 9), while the value of correction coefficient K3 is lowered during downshifts (one point In the case of (dashed line, two-dot chain line), the value of the correction coefficient K3 is not increased and is set to the maximum value 1, which is the same as the normal drive range. This is to prevent the deceleration torque from becoming too large and reaching the slip limit by increasing the correction coefficient K3 during downshifting. Generally, when downshifting, the accelerator opening required to maintain the same vehicle speed increases; however, by setting the correction coefficient K3 according to the gear position as shown in FIG. Even if the speed increases, the value of the correction coefficient K3 remains approximately constant for the same vehicle speed.

Here, when the automatic transmission 5 is switched to the low speed side, the target acceleration set for the operation amount of the accelerator pedal 10 is lower than when it is switched to the high speed side. That is, when the accelerator pedal 10 is depressed a certain amount, the set target acceleration is lower when the automatic transmission 5 is switched to the low speed side than when it is switched to the high speed side. . Therefore, it can be said that the transmission sensor 5a, which is a vehicle state detection unit that detects the gear position of the automatic transmission 5, detects the target acceleration with respect to the operation amount of the accelerator pedal 10. When the gear detected by the transmission sensor 5a is a low gear, the target acceleration with respect to the operating amount of the accelerator pedal 10 becomes small, and conversely, when the gear is a high gear, the accelerator pedal The target acceleration for the manipulated variable of 10 becomes large.

Furthermore, as shown in the dashed line and dashed double dotted line in FIG. Torque is corrected to a larger value. On the other hand, as shown by the broken lines and dotted lines in FIG. Torque is corrected to a smaller value.

In this way, in the vehicle drive system of this embodiment, the additional deceleration and the deceleration torque set based on this are corrected based on the operating amount of the accelerator pedal 10, but the correction coefficient K3 is The value is corrected based on the gear position (target acceleration relative to the amount of operation of the accelerator pedal). As a result, even when the deceleration torque is corrected based on the operation amount of the accelerator pedal 10, it becomes possible to add the same degree of deceleration torque to the same target acceleration, and consistent vehicle attitude control is executed. It does not make the driver feel uncomfortable.

Next, FIG. 10 is a map showing the relationship between the additional deceleration correction coefficient K4 determined by the deceleration torque determination unit 20 and the required deceleration according to the embodiment of the present invention. The horizontal axis in FIG. 10 indicates the required deceleration detected by the brake fluid pressure sensor 14, and the vertical axis indicates the correction coefficient K4. As shown in FIG. 10, when the required deceleration is less than 1 m/s ² , the correction coefficient K4 is set to become smaller as the required deceleration increases. When the required deceleration is 1 m/s ² or more, the correction coefficient K4 is constant at a minimum value of 0. Further, when the required deceleration is 0 m/s ² , the correction coefficient K4 has a maximum value of 1.

In step S41 of FIG. 5, the maps shown in FIGS. 6 to 10 are used to determine correction coefficients K1, K2, K3, and K4 corresponding to vehicle speed, steering angle, accelerator opening, and required deceleration, respectively. is set. Next, the process proceeds to step S42, and the deceleration torque determining unit 20 determines the target additional deceleration by multiplying the target additional deceleration obtained in step S24 of FIG. 4 by all of the correction coefficients K1, K2, K3, and K4. (Hereinafter, the additional deceleration after correction will be referred to as "corrected additional deceleration" as necessary).

Next, in step S43, the deceleration torque determination unit 20 determines whether the corrected additional deceleration is less than a predetermined threshold value D _T (for example, 0.05 m/s ² ).

As a result, if the corrected additional deceleration is less than the threshold value _D It is determined whether the obtained value is less than a threshold value _DT .

As a result, if the value obtained by multiplying the target additional deceleration by the correction coefficients K1 and K2 is less than the threshold value _D Therefore, the process proceeds to step S45, and the deceleration torque determination unit 20 sets the corrected additional deceleration to zero even if the torque reduction control is stopped. That is, the torque reduction is stopped. Thereafter, the deceleration torque determination unit 20 ends the additional deceleration correction process.

On the other hand, if the value obtained by multiplying the target additional deceleration by the correction coefficients K1 and K2 is not less than the threshold value D _T (or more than the threshold value D _T ), the process proceeds to step S46, and the deceleration torque determination unit 20 performs step S24 in FIG. It is determined whether the value obtained by multiplying the target additional deceleration obtained in step 2 by the correction coefficients K3 and K4 is less than the threshold value _DT .

As a result, if the value obtained by multiplying the target additional deceleration by the correction coefficients K3 and K4 is less than the threshold value _D First, it is considered that the corrected additional deceleration is less than the threshold value D _T because the accelerator opening is large or the required deceleration is large. In this case, if the torque reduction control is stopped, the turning performance of the vehicle will be slightly reduced, resulting in changes in the reaction force of the steering wheel and changes in the direction of travel of the vehicle, which may give the driver a sense of discomfort. . Therefore, the deceleration torque determination unit 20 ends the additional deceleration correction process without setting the corrected additional deceleration calculated in step S42 to 0. That is, the reduction in torque is maintained.

On the other hand, if the value obtained by multiplying the target additional deceleration by the correction coefficients K3 and _K4 is not less than the threshold _D Since it is considered that the situation is not high, the process proceeds to step S45, and the deceleration torque determination unit 20 sets the corrected additional deceleration to zero. That is, the torque reduction is stopped.

Furthermore, in step S46, if the corrected additional deceleration is not less than _the threshold value _D The additional deceleration correction processing is ended without setting the corrected additional deceleration to zero. That is, the reduction in torque is maintained.

Returning to FIG. 4, after the additional deceleration correction processing in step S25, in step S26, the deceleration torque determination unit 20 determines that the increase rate of the additional deceleration after correction is equal to or less than the threshold value Rmax (for example, 0.5 m/s ³ ). The additional deceleration for this process is determined within the range.
Specifically, if the rate of increase from the additional deceleration determined in the previous process to the additional deceleration corrected in step S25 of the current process is less than or equal to Rmax, the deceleration torque determination unit 20 determines that The additional deceleration is determined as the additional deceleration in the current process.

On the other hand, if the rate of change from the additional deceleration determined in the previous process to the additional deceleration corrected in step S25 of the current process is greater than Rmax, the deceleration torque determination unit 20 determines the additional deceleration determined in the previous process. The value increased by the increase rate Rmax from to the time of the current processing is determined as the additional deceleration in the current processing.

Further, in step S23, if the absolute value of the steering speed is decreasing, the process proceeds to step S27, and the deceleration torque determination unit 20 determines the additional deceleration determined in the previous process as the additional deceleration in the current process. . That is, when the absolute value of the steering speed is decreasing, the additional deceleration at the maximum steering speed (that is, the maximum value of the additional deceleration) is maintained.

Further, in step S21, if the absolute value of the steering angle is not increasing (constant or decreasing), the process proceeds to step S28, and the deceleration torque determination unit 20 changes the additional deceleration determined in the previous process to the current value. Obtain the amount to be reduced in processing (deceleration reduction amount). This deceleration reduction amount is calculated, for example, based on a constant reduction rate (for example, 0.3 m/s ³ ) that is stored in advance in a memory or the like. Alternatively, it is calculated based on the reduction rate determined according to the driving state of the vehicle 1 acquired in step S1 and the steering speed calculated in step S22.

Then, in step S29, the deceleration torque determining unit 20 determines the additional deceleration in the current process by subtracting the deceleration reduction amount obtained in step S28 from the additional deceleration determined in the previous process.

After step S26, S27, or S29, in step S30, the deceleration torque determination unit 20 determines the deceleration torque based on the current additional deceleration determined in step S26, S27, or S29. Specifically, the deceleration torque determination unit 20 determines the deceleration torque required to realize the current additional deceleration based on the current vehicle speed, road surface slope, etc. acquired in step S1. After step S31, the deceleration torque determination section 20 ends the deceleration torque determination process and returns to the main routine shown in FIG. 3.

Returning to FIG. 3, after performing the processing in steps S2 and S3 and the deceleration torque determination processing in step S4, in step S5, the final target torque determination unit 22 calculates the basic target torque from the basic target torque after smoothing in step S4. , the final target torque is determined by subtracting the deceleration torque determined in the deceleration torque determination process of step S4.

Next, in step S6, the engine control unit 24 controls the engine 4 to output the final target torque set in step S5. Specifically, the engine control unit 24 determines various state quantities (for example, air filling amount, fuel injection amount, intake air temperature, oxygen concentration, etc.), and controls each actuator that drives each component of the engine 4 based on these state quantities. In this case, the engine control unit 24 sets a limit value and a limit range according to the state quantity, sets a control amount for each actuator such that the state value complies with the limit value and the limit range, and executes control. do.
After step S6, the PCM 16 ends the engine control process.

Next, the operation of the vehicle drive system according to the first embodiment of the present invention will be explained with reference to FIG. FIG. 11 is a time chart showing changes in parameters related to engine control by the vehicle drive system when the vehicle 1 equipped with the vehicle drive system according to the first embodiment of the present invention makes a turn.

FIG. 11(a) is a plan view schematically showing the vehicle 1 making a right turn. As shown in FIG. 11(a), the vehicle 1 starts turning to the right from position A, and continues turning to the right from position B to position C with a constant steering angle.

FIG. 11(b) is a diagram showing changes in the steering angle of the vehicle 1 making a right turn as shown in FIG. 11(a). The horizontal axis in FIG. 11(b) indicates time, and the vertical axis indicates steering angle.
As shown in FIG. 11(b), rightward steering starts at position A, the absolute value of the rightward steering angle gradually increases as the steering wheel is turned, and at position B, the absolute value of the rightward steering angle gradually increases. value is maximum. Thereafter, the steering angle is kept constant until position C (steering held).

FIG. 11(c) is a diagram showing changes in the steering speed of the vehicle 1 making a right turn as shown in FIG. 11(b). The horizontal axis in FIG. 11(b) shows time, and the vertical axis shows steering speed.
The steering speed of the vehicle 1 is expressed by the time differential of the steering angle of the vehicle 1. That is, as shown in FIG. 11(c), when rightward steering is started at position A, a rightward steering speed is generated, and the steering speed is kept almost constant between positions A and B. Thereafter, the rightward steering speed decreases, and when the rightward steering angle reaches the maximum at position B, the steering speed becomes 0. Furthermore, while the rightward steering angle is maintained from position B to position C, the steering speed remains at zero.

FIG. 11(d) is a diagram showing changes in the additional deceleration determined based on the steering speed shown in FIG. 11(c). The horizontal axis in FIG. 11(d) indicates time, and the vertical axis indicates additional deceleration.
The deceleration torque determination unit 20 increases the additional deceleration as the steering speed increases, and in a region where the steering speed is kept approximately constant, the additional deceleration is also kept approximately constant.
Further, as described above, when the absolute value of the steering speed is decreasing in step S23 of FIG. 4, the deceleration torque determination unit 20 holds the additional deceleration at the time of the maximum steering speed. In FIG. 11(d), when the steering speed decreases toward position B, the target additional deceleration indicated by the dashed line also decreases, but the additional deceleration indicated by the solid line reaches its maximum value until position B. maintain.

Furthermore, as described above, if the absolute value of the steering angle is constant or decreasing in step S21 of FIG. Then, in step S30, the additional deceleration is reduced by the corrected deceleration reduction amount. In FIG. 11(d), the deceleration torque determining unit 20 reduces the additional deceleration so that the rate of decrease in the additional deceleration gradually becomes smaller, that is, the change in the additional deceleration becomes gradually gentler.

FIG. 11(e) is a diagram showing changes in deceleration torque determined based on the additional deceleration shown in FIG. 11(d). The horizontal axis in FIG. 11(e) indicates time, and the vertical axis indicates deceleration torque.
As described above, the deceleration torque determination unit 20 determines the deceleration torque required to achieve additional deceleration based on parameters such as the current vehicle speed and road surface slope. Therefore, when these parameters are constant, the deceleration torque is determined to change in the same way as the additional deceleration shown in FIG. 11(d).

FIG. 11(f) is a diagram showing changes in the final target torque determined based on the basic target torque and the deceleration torque. The horizontal axis in FIG. 11(f) shows time, and the vertical axis shows torque. Moreover, the dotted line in FIG. 11(f) indicates the basic target torque, and the solid line indicates the final target torque.
As described with reference to FIG. 3, the final target torque determination unit 22 subtracts the deceleration torque determined in the deceleration torque determination process of step S4 from the basic target torque determined in step S3, thereby determining the final target torque. Determine.

FIG. 11(g) shows the change in the yaw rate (actual yaw rate) that occurs in the vehicle 1 when the engine 4 is controlled based on the final target torque shown in FIG. 11(f), and the change determined by the deceleration torque determination unit. The graph shows the change in the actual yaw rate when the engine 4 is not controlled based on the deceleration torque (that is, when the engine 4 is controlled to achieve the basic target torque shown by the dotted line in FIG. 11(f)). It is a line diagram. The horizontal axis in FIG. 11(g) shows time, and the vertical axis shows yaw rate. Furthermore, the solid line in FIG. 11(g) shows the change in the actual yaw rate when the engine 4 is controlled to achieve the final target torque, and the dotted line shows the change in the actual yaw rate when the control corresponding to the deceleration torque is not performed. Shows changes in actual yaw rate.

Rightward steering is started at position A, and as the rightward steering speed increases, the deceleration torque is increased as shown in FIG. 11(e), thereby achieving the final target torque as shown in FIG. 11(f). When the load is reduced, the load on the front wheels 2, which are the steered wheels of the vehicle 1, increases. As a result, the frictional force between the front wheels 2 and the road surface increases, and the cornering force of the front wheels 2 increases, so that the turning performance of the vehicle 1 improves. That is, as shown in FIG. 11(g), between position A and position B, the final target torque that reflects the deceleration torque is achieved more than when no control corresponding to the deceleration torque is performed (dotted line). When the engine 4 is controlled in this manner (solid line), the clockwise (CW) yaw rate generated in the vehicle 1 becomes larger.

Next, as shown in Figs. 11(d) and (e), when the steering speed decreases toward position B, the target additional deceleration also decreases, but since the deceleration torque is maintained at its maximum value, As long as the steering is continued, the load applied to the front wheels 2 is maintained, and the turning performance of the vehicle 1 is maintained.

Furthermore, when the absolute value of the steering angle is constant from position B to position C, the final target torque is smoothly increased by smoothly decreasing the deceleration torque. By reducing the load applied to the front wheels 2 and the cornering force of the front wheels 2, the output torque of the engine 4 can be restored while stabilizing the vehicle body.

According to the vehicle drive system of the first embodiment of the present invention, when the target acceleration with respect to the operation amount of the accelerator pedal 10 is small (for example, the one-dot chain line and the two-dot chain line in FIG. 9), when the target acceleration is large (for example, , broken line, dotted line in FIG. 9), the correction coefficient K3 is set to a larger value, and thereby the deceleration torque in vehicle attitude control is corrected to a larger value. Therefore, even if the relationship between the operation amount of the accelerator pedal 10 and the target acceleration changes, substantially the same deceleration torque can be set for the same steering and target acceleration. As a result, it is possible to prevent the vehicle attitude control from varying depending on the operating amount of the accelerator pedal 10 for the same driving state of the vehicle 1, and it is possible to prevent the driver from feeling uncomfortable. can.

Further, according to the vehicle drive system of the present embodiment, even when the operating amount of the accelerator pedal 10 to obtain the same acceleration is changed by changing the gear stage of the automatic transmission 5, the same vehicle posture can be maintained. The control is executed and it is possible to prevent the driver from feeling uncomfortable.

Furthermore, according to the vehicle drive system of this embodiment, even if the gear position of the automatic transmission 5 is changed and the relationship between the operation amount of the accelerator pedal 10 and the target acceleration is changed, the same vehicle attitude control is executed. This can prevent the driver from feeling uncomfortable.

As described above, in the first embodiment of the present invention, the vehicle drive system of the present invention is applied to a front wheel drive vehicle, but as a modification, the present invention can also be applied to a rear wheel drive vehicle. In this case, the controller PCM 16 sets the acceleration torque based on the steering speed detected by the steering angle sensor 8 and the operation amount of the accelerator pedal 10 detected by the accelerator opening sensor 10a, and sets the acceleration torque. Based on this, vehicle attitude control is executed by modifying the basic target torque corresponding to the target acceleration.

Further, in the first embodiment described above, the map of the correction coefficient K3 (FIG. 9), which is the accelerator opening degree gain, was changed depending on the gear position of the automatic transmission 5, but even in a rear-wheel drive vehicle. The map changes as well. That is, even in a rear-wheel drive vehicle, when the target acceleration relative to the operating amount of the accelerator pedal 10 is small (when the automatic transmission 5 is in a low gear), the PCM 16 determines that the target acceleration relative to the operating amount of the accelerator pedal 10 is small (when the automatic transmission 5 is in a low gear position). The acceleration torque is corrected to a larger value than when it is large (in the high speed gear). Thereby, even if the relationship between the operation amount of the accelerator pedal 10 and the target acceleration changes, substantially the same acceleration torque can be set for the same steering and target acceleration. As a result, it is possible to prevent the vehicle attitude control from varying depending on the operation amount of the accelerator pedal 10 for the same driving state of the vehicle 1, and it is possible to prevent the driver from feeling uncomfortable. can.

Next, a vehicle drive system according to a second embodiment of the present invention will be described with reference to FIGS. 12 and 13.
The vehicle drive system of this embodiment differs from the first embodiment of the present invention described above in that the vehicle to which it is applied is an electric vehicle equipped with a rotating electric machine (motor/generator) as a prime mover. Therefore, only the points of the second embodiment of the present invention that are different from the first embodiment will be explained here, and explanations of similar configurations, operations, and effects will be omitted. FIG. 12 is a block diagram showing the overall configuration of a vehicle equipped with a vehicle drive system according to a second embodiment of the present invention. FIG. 13 is a torque control map showing the relationship between the accelerator pedal opening and the output torque and regenerative torque of the rotating electric machine.

As shown in FIG. 12, the electric vehicle 100 is an electric vehicle equipped with a rotating electric machine 104 that is a prime mover. The rotating electric machine 104 is mounted, for example, on the front part of the electric vehicle 100. Torque output from rotating electrical machine 104 is transmitted to reduction gear 105. The speed reducer 105 outputs the output torque of the rotating electric machine 104 to the pair of drive shafts at a single speed reduction ratio. As a result, a pair of drive wheels 102 (left and right front wheels in the example of FIG. 12) attached to the outer ends of each drive shaft in the vehicle width direction are driven.

A battery 122 that supplies power to the rotating electrical machine 104 is mounted, for example, in the rear part of the electric vehicle 100. Furthermore, an inverter 118 is arranged near the rotating electric machine 104. The inverter 118 converts DC power supplied from the battery 122 into AC power and supplies it to the rotating electrical machine 104, or converts regenerative power generated by the rotating electrical machine 104 into DC power and supplies it to the battery 122. The battery 122 is charged. Further, the inverter 118 is electrically connected to a PCM 116 (Power-train Control Module) which is a controller, and is capable of inputting and outputting control signals to and from the PCM 116.

The electric vehicle 100 also includes a steering device 106 for steering the vehicle, a steering angle sensor 108 for detecting a steering angle by the steering device 106, an accelerator opening sensor 110, and a vehicle speed sensor 112. The above-mentioned rotating electric machine 104, steering device 106, steering angle sensor 108, accelerator opening sensor 110, and PCM 116 constitute a vehicle drive system according to the second embodiment of the present invention.

Further, the accelerator opening sensor 110 is configured to detect the operation amount of the accelerator pedal (corresponding to the amount by which the driver depresses the accelerator pedal). Each of the above-mentioned sensors is directly or indirectly electrically connected to the PCM 116, and outputs a detection signal corresponding to each detection value to the PCM 116.

Further, the electric vehicle 100 includes a paddle switch 106b provided on the steering wheel 106a of the steering device 106, and a shifter 120 provided on the center console. These paddle switches 106b and shifter 120 are arranged at positions where the driver can operate them while driving, and are directly or indirectly electrically connected to the PCM 116. When the paddle switch 106b and the shifter 120 are operated by the driver, they output an operation signal to the PCM 116 in accordance with the operation.

In this electric vehicle 100, the PCM 116 performs various controls. In this embodiment, the PCM 116 functions as a controller for the vehicle drive system of the electric vehicle 100. The PCM 116 controls the inverter 118 in response to the operation of the accelerator pedal by the driver, and causes the battery 122 to supply power to the rotating electrical machine 104 via the inverter 118, or supplies regenerative power from the rotating electrical machine 104 to the battery 122. By doing so, the desired output torque or regenerative torque is realized in accordance with the accelerator operation. That is, the PCM 116 is configured to set the target acceleration based on the operation amount of the accelerator pedal detected by the accelerator opening sensor 110.

The PCM 116 is used to store a processor, various programs that are interpreted and executed on the processor (including basic control programs such as the OS, and application programs that are started on the OS and realize specific functions), and various data. memory (not shown). The PCM 116 also sets a deceleration torque based on the steering speed detected by the steering angle sensor 108 and the operation amount of the accelerator pedal detected by the accelerator opening sensor 110, and adjusts the target acceleration to the target acceleration based on this deceleration torque. The vehicle attitude control is configured to perform vehicle attitude control that modifies the corresponding basic target torque.

A pair of paddle switches 106b are provided on the back side of the steering wheel 106a (on the side opposite to the driver). In this embodiment, the operation of pulling the right paddle switch 106b toward you when viewed from the driver's seat side will be referred to as a "plus operation," and the operation of pulling the left paddle switch 106b toward you will be referred to as a "minus operation." When either or both paddle switches 106b are operated, an operation signal corresponding to the operated paddle switch 106b is output to the PCM 116. Thereby, the processor (not shown) built into the PCM 116 detects that the paddle switch 106b has been operated by the driver.

That is, the processor of the PCM 116 functions as a vehicle state detection unit that detects the generated torque of the rotating electric machine 104 and the regenerated torque of the rotating electric machine 104 in response to the operation amount of the accelerator pedal, and also functions as a part of the vehicle drive system of this embodiment. constitute the department. In other words, the PCM 116 functions as a vehicle state detection unit that detects the relationship between the amount of operation of the accelerator pedal and the set target acceleration, and also detects the amount of operation of the accelerator pedal required to maintain the same vehicle speed.

Further, the shifter 120 is configured to be switched by the driver to a parking range (P range), a reverse range (R range), a drive range (D range), or a manual range (M range). The shifter 120 is provided with a shift position sensor for detecting the position of the shift lever, so that it can detect whether the shift lever is placed in the P range, R range, D range, or M range. It has become. Additionally, sensors are provided before and after the M range to detect shift lever operations to the front and rear of the M range. When the shift lever is operated, these sensors output operation signals to the PCM 116 according to the position of the shift lever.

In addition, in the M range, the shift lever can be moved forward or backward, which allows you to perform a "plus operation" by pulling the right paddle switch 106b toward you, and a "minus operation" by pulling the left paddle switch 106b toward you. Equivalent operations can be performed.

Next, with reference to FIG. 13, the relationship between the accelerator pedal opening and the output torque and regenerative torque of the rotating electrical machine 104 will be described. FIG. 13 is a diagram showing an example of a torque control map for each vehicle speed according to the present embodiment. Specifically, FIG. 13(a) shows a torque control map applied at a vehicle speed of 30 km/h, FIG. 13(b) shows a torque control map applied at a vehicle speed of 60 km/h, and FIG. c) shows a torque control map applied at a vehicle speed of 100 km/h. In each of FIGS. 13A to 13C, the horizontal axis shows the accelerator pedal opening [%], and the vertical axis shows the torque [Nm] of the rotating electrical machine 104. Further, when the torque on the vertical axis is a positive value, it indicates the output torque of the rotating electrical machine 104, and when it is a negative value, it indicates the regenerative torque of the rotating electrical machine 104.

Note that FIG. 13 only shows torque control maps applied at 30 km/h, 60 km/h, and 100 km/h as examples, and in reality, there are torque control maps applied at various vehicle speeds other than these. It will be prepared. These torque control maps are stored in the processor (not shown) of PCM 116.

In this embodiment, the relationship between the opening degree of the accelerator pedal and the output torque and regenerative torque of the rotating electric machine 104 can be changed by operating the paddle switch 106b or by operating the shifter 120 back and forth in the M range. I can do it. Specifically, as shown in FIGS. 13(a), (b), and (c), five levels of torque control maps are prepared for each vehicle speed: D--, D-, D, D+, and D++. . In these torque control maps, the output torque of the rotating electric machine 104 corresponding to the same accelerator pedal opening increases in the order of D--, D-, D, D+, and D++. Furthermore, the regenerative torque of the rotating electric machine 104 corresponding to the same accelerator pedal opening decreases in the order of D--, D-, D, D+, and D++. In other words, the target acceleration relative to the operation amount of the accelerator pedal is changed by operating the paddle switch 106b or the like. This change is then detected by the PCM 116.

Moreover, in any of the torque control maps, the regenerative torque of the rotating electric machine 104 is set to be smaller and the output torque is set to be larger as the accelerator pedal opening becomes larger. Then, as the accelerator pedal opening approaches 100%, the output torque of the rotating electrical machine 104 in each of the torque control maps D--, D-, D, D+, and D++ converges to the maximum output torque at each vehicle speed. It has become. Further, as the vehicle speed increases, the accelerator pedal opening at which the output torque becomes 0 (the regenerative torque also becomes 0) is set to increase. In this embodiment, the accelerator pedal opening at which the output torque is 0 (regenerative torque is also 0) is approximately 10 to 25% when the vehicle speed is 30 km/h, approximately 15 to 30% when the vehicle speed is 60 km/h, At 100 km/h, it is approximately 20-40%.

On the other hand, also in this embodiment, the PCM 116 sets the deceleration torque based on the steering speed detected by the steering angle sensor 108 and the operation amount of the accelerator pedal detected by the accelerator opening sensor 110, and Based on the target acceleration, the vehicle attitude control is configured to modify the basic target torque corresponding to the target acceleration. This vehicle attitude control is equivalent to the vehicle attitude control in the vehicle drive system according to the first embodiment of the present invention described with reference to FIGS. 3 to 10.

That is, also in this embodiment, the set deceleration torque is corrected by the same correction coefficients K1 to K4 as shown in FIGS. 7 to 10, and the final deceleration torque is determined. In the first embodiment described above, the correction coefficient K3 (accelerator opening gain) set based on the accelerator opening shown in FIG. A different map was applied. On the other hand, the vehicle drive system of this embodiment is applied to an electric vehicle 100, and a configuration corresponding to the automatic transmission 5 is not provided. However, also in this embodiment, as shown in FIG. 13, the target acceleration relative to the operation amount of the accelerator pedal is changed by operating the paddle switch 106b or the like.

For this reason, also in this embodiment, the map for setting the correction coefficient K3, which is set based on the accelerator opening degree, is changed depending on the operating state of the paddle switch 106b and the like. For example, in a state where the torque control map indicated by "D" in FIG. 13 is applied, the correction coefficient K3 can be set using the map indicated by the solid line in FIG. In addition, for "D+" in FIG. 13, the map shown by the broken line in FIG. 9 is used, for "D++" in FIG. 13, the map shown by the dotted line in FIG. 9 is used, and for "D-" in FIG. In "D--" in FIG. 13, the correction coefficient K3 can be set using the map indicated by the two-dot chain line in FIG.

As a result, when the target acceleration for the same accelerator pedal operation amount is small (for example, in the case of D-, D--), the correction coefficient K3 is set to a large value. By setting the correction coefficient K3 in this manner, when the target acceleration relative to the amount of operation of the accelerator pedal is small, the deceleration torque is corrected to a larger value than when the target acceleration relative to the amount of operation of the accelerator pedal is large. As a result, even if the deceleration torque is corrected based on the amount of operation of the accelerator pedal, it is possible to add the same degree of deceleration torque to the same target acceleration, and consistent vehicle attitude control is executed, allowing driving It does not make people feel uncomfortable.

According to the vehicle drive system of the second embodiment of the present invention, the PCM 116 functioning as a vehicle state detection section detects the generated torque of the rotating electrical machine 104 and the regenerative torque of the rotating electrical machine 104 with respect to the operation amount of the accelerator pedal. Ru. As a result, although the relationship between the operation amount of the accelerator pedal and the target acceleration is changed, by changing the map for setting the correction coefficient K3, the same vehicle attitude control can be executed, and the driver may feel an discomfort. can be prevented from giving.

Further, in the second embodiment of the present invention, the present invention is applied to a front wheel drive vehicle driven by the rotating electric machine 104, but the present invention is also applied to a rear wheel drive vehicle driven by the rotating electric machine 104. The invention can be applied. In this case, the vehicle drive system according to the second embodiment of the present invention may be changed as in the modification to the first embodiment.

Although the vehicle drive system according to the embodiment of the present invention has been described above, various changes can be made to the embodiment described above. In particular, in the embodiments described above, the present invention was applied to an engine vehicle equipped with an automatic transmission and an electric vehicle equipped with a rotating electric machine, but engine vehicles equipped with a manual transmission, hybrid vehicles, etc. , the present invention can be applied to vehicles equipped with various drive systems.

1 Vehicle 2 Front wheels 4 Engine (prime mover)
5 Automatic transmission 5a Transmission sensor (vehicle condition detection section)
6 Steering device 6a Steering wheel 6b Paddle switch (speed change operation part)
8 Steering angle sensor 10 Accelerator pedal 10a Accelerator opening sensor 12 Vehicle speed sensor 14 Brake fluid pressure sensor 16 PCM (controller)
18 Basic target torque determination unit 20 Deceleration torque determination unit 22 Final target torque determination unit 24 Engine control unit 100 Electric vehicle 102 Drive wheels 104 Rotating electric machine (prime mover)
106 Steering device 106a Steering wheel 106b Paddle switch 105 Reducer 108 Steering angle sensor 110 Accelerator opening sensor 112 Vehicle speed sensor 116 PCM (controller, vehicle condition detection unit)
118 Inverter 120 Shifter 122 Battery

Claims (4)

A vehicle drive system equipped with a vehicle attitude control function,
a prime mover that generates driving force to drive the front wheels of the vehicle;
automatic transmission and
a steering device for steering the vehicle;
a steering angle sensor for detecting a steering angle by this steering device;
an accelerator opening sensor that detects the amount of accelerator pedal operation by the driver;
a controller that sets a target acceleration based on the operation amount of the accelerator pedal detected by the accelerator opening sensor;
a vehicle state detection unit that detects the relationship between the operation amount of the accelerator pedal detected by the accelerator opening sensor and the set target acceleration;
has
The controller sets a deceleration torque based on the steering speed detected by the steering angle sensor and the operation amount of the accelerator pedal detected by the accelerator opening sensor, and adjusts the target acceleration based on this deceleration torque. is configured to perform vehicle attitude control that corrects a basic target torque corresponding to the
The vehicle state detection unit detects a relationship between an operation amount of an accelerator pedal and a set target acceleration by detecting a gear position of the automatic transmission,
The controller corrects the deceleration torque to a larger value when the target acceleration relative to the operating amount of the accelerator pedal detected by the vehicle state detection section is small than when the target acceleration relative to the operating amount of the accelerator pedal is large. A vehicle drive system characterized by: A vehicle drive system equipped with a vehicle attitude control function,
a prime mover that generates driving force to drive the rear wheels of the vehicle;
automatic transmission and
a steering device for steering the vehicle;
a steering angle sensor for detecting a steering angle by this steering device;
an accelerator opening sensor that detects the amount of accelerator pedal operation by the driver;
a controller that sets a target acceleration based on the operation amount of the accelerator pedal detected by the accelerator opening sensor;
a vehicle state detection unit that detects the relationship between the operation amount of the accelerator pedal detected by the accelerator opening sensor and the set target acceleration;
has
The controller sets acceleration torque based on the steering speed detected by the steering angle sensor and the operation amount of the accelerator pedal detected by the accelerator opening sensor, and based on this acceleration torque, the target acceleration is set. is configured to perform vehicle attitude control that corrects a basic target torque corresponding to the
The vehicle state detection unit detects a relationship between an operation amount of an accelerator pedal and a set target acceleration by detecting a gear position of the automatic transmission,
The controller corrects the acceleration torque to a larger value when the target acceleration relative to the operating amount of the accelerator pedal detected by the vehicle state detection section is small than when the target acceleration relative to the operating amount of the accelerator pedal is large. A vehicle drive system characterized by: 3. The vehicle drive system according to claim 1, wherein the vehicle state detection section is configured to detect an amount of operation of an accelerator pedal required to maintain the same vehicle speed. The prime mover is a rotating electrical machine, and the vehicle state detection unit detects the generated torque of the rotating electrical machine and the regenerative torque of the rotating electrical machine in response to the operating amount of the accelerator pedal, and detects the operating amount of the accelerator pedal. The vehicle drive system according to any one of claims 1 to 3, wherein a relationship between set target accelerations is detected.

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