Vehicle control method and vehicle control device

Abstract

The present invention provides a vehicle control method and a vehicle control device that, in a vehicle in which the driven wheels have been replaced with motor-driven wheels, can promote the power consumption of the motor-driven wheels and facilitate continuous assistance in decelerating the vehicle. [Solution] A vehicle 101 is controlled in which the driven wheels 17 of a base vehicle 100 having a behavior stabilization device 12 using friction brakes 11 are replaced with motor-driven wheels 20 configured using a battery 21, an inverter 22, and an in-wheel motor 23. At this time, if the state of charge (SOC) of the battery 21 is above a predetermined threshold Th, the motor-driven wheels 20 are powered, and the friction brakes 11 are activated using the behavior stabilization device 12, thereby offsetting the motor torque generated by the motor-driven wheels 20 during power control with the friction torque generated by the friction brakes 11.

Description

[Technical Field]

[0001] This invention relates to a vehicle control method and a vehicle control device. [Background technology]

[0002] Patent Document 1 discloses a hybrid vehicle comprising an engine that drives the rear wheels, a main drive motor that drives the rear wheels, and a secondary drive motor that drives the front wheels, wherein the secondary drive motor is a so-called in-wheel motor. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] International Publication No. 2019 / 181933 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] In some cases, the driven wheels of a two-wheel drive vehicle may be replaced with drive wheels equipped with in-wheel motors (hereinafter referred to as motor-driven wheels). These motor-driven wheels include, in addition to the in-wheel motors, an inverter and battery to drive the in-wheel motors. These aftermarket motor-driven wheels are then controlled, for example, to assist or support the acceleration or deceleration of the vehicle.

[0005] However, the batteries included in aftermarket motor-driven wheels are typically small in capacity. For example, compared to the batteries installed in electric vehicles designed from the outset to be motor-driven, the capacity of the batteries in aftermarket motor-driven wheels is very small. As a result, the battery capacity can become a bottleneck, preventing the motor-driven wheels from continuously assisting with acceleration and deceleration. In particular, when driving a vehicle with driven wheels replaced with motor-driven wheels, the batteries in the motor-driven wheels often quickly become fully charged, preventing the motor-driven wheels from assisting with deceleration.

[0006] The present invention aims to provide a vehicle control method and a vehicle control device that can facilitate the continuous deceleration of a vehicle in which the driven wheels have been replaced with motor-driven wheels by promoting the power consumption of the motor-driven wheels. [Means for solving the problem]

[0007] One aspect of the present invention is a vehicle control method for controlling a vehicle in which the driven wheels of a base vehicle having a behavior stabilization device using friction brakes have been replaced with motor-driven wheels configured using a battery, an inverter, and an in-wheel motor. In this vehicle control method, when the battery charge level is above a predetermined threshold, the motor-driven wheels are powered and the friction brakes are activated using the behavior stabilization device, thereby offsetting the motor torque generated by the motor-driven wheels during power control with the friction torque generated by the friction brakes. [Effects of the Invention]

[0008] According to the present invention, in a vehicle in which the driven wheels have been replaced with motor-driven wheels, it is possible to provide a vehicle control method and a vehicle control device that promote power consumption of the motor-driven wheels and facilitate continuous assistance in decelerating the vehicle. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is an explanatory diagram showing the schematic configuration of the base vehicle. [Figure 2] Figure 2 is an explanatory diagram showing the schematic configuration of the vehicle according to this embodiment. [Figure 3] Figure 3 is an explanatory diagram showing the modified configuration of the vehicle according to this embodiment. [Figure 4] Figure 4 is a block diagram showing the configuration of the MCU. [Figure 5] Figure 5 is a flowchart showing the control of the motor-driven wheels. [Figure 6] Figure 6 is an explanatory diagram showing a typical operating pattern of an in-wheel motor and friction brake in power consumption control. [Figure 7] Figure 7 is an explanatory diagram showing a typical operating pattern of an in-wheel motor and friction brake in power consumption control. [Figure 8] Figure 8 is a flowchart illustrating the control of the motor-driven wheels when the vehicle is turning. [Figure 9] Figure 9 is an explanatory diagram showing a typical operating pattern of the in-wheel motor and friction brake when the motion stabilization device is activated during turning. [Figure 10] Figure 10 is an explanatory diagram showing a typical operating pattern of the in-wheel motor and friction brake when the motion stabilization device is not activated during turning. [Modes for carrying out the invention]

[0010] Embodiments of the present invention will be described below with reference to the drawings.

[0011] Figure 1 is an explanatory diagram showing the schematic configuration of the base vehicle 100. The base vehicle 100 is a two-wheel drive vehicle in which either the front wheels or the rear wheels are drive wheels and the other is a driven wheel. In this embodiment, as an example, the base vehicle 100 is assumed to be a front-wheel drive vehicle. That is, in this embodiment, the front wheels of the base vehicle 100 are drive wheels and the rear wheels are driven wheels. Also, in this embodiment, the base vehicle 100 is assumed to be an engine-driven vehicle (a so-called engine-powered vehicle). However, the base vehicle 100 may be a rear-wheel drive vehicle, or it may be an electric vehicle or a hybrid vehicle.

[0012] As shown in Figure 1, the base vehicle 100 is equipped with an engine 10 (ENG), friction brakes 11, and a vehicle stabilization device 12.

[0013] Engine 10 is an internal combustion engine that generates power using gasoline or other fuel, and is the power source for the base vehicle 100.

[0014] The torque output by the engine 10 (hereinafter referred to as engine torque) is transmitted to the drive wheels via the reduction gear 13, clutch (not shown), differential gear 14, and drive shaft 15, etc. In this embodiment, as described above, the drive wheels of the base vehicle 100 are the front wheels. Hereinafter, the drive wheels (front wheels) of the base vehicle 100 will be referred to as the main drive wheels 16. The rear wheels of the base vehicle 100 are the driven wheels 17.

[0015] The operation of the engine 10 is controlled by the ECU 18 (Engine Control Unit). The ECU 18 controls the rotation of the engine 10 according to the amount the driver operates the accelerator pedal (not shown). The ECU 18 is composed of, for example, one or more computers.

[0016] The friction brake 11 is a braking device that slows the base vehicle 100 using frictional force. A friction brake 11 is provided on each wheel of the base vehicle 100. In principle, the friction brakes 11 are operated simultaneously by the driver's operation of the brake pedal (not shown). However, the friction brakes 11 can be operated individually for each wheel. Hereinafter, the torque generated by each wheel when the friction brake 11 is operated will be referred to as friction torque. Friction torque is adjustable.

[0017] The behavior stabilization device 12 is a device that stabilizes the behavior of the base vehicle 100. In this embodiment, the behavior stabilization device 12 suppresses skidding of the base vehicle 100 by appropriately activating the friction brakes 11 of each wheel. In other words, in this embodiment, the behavior stabilization device 12 is a so-called electronic stability control (ESC). The behavior stabilization device 12 is also generally referred to as VDC (Vehicle Dynamics Control) or VSC (Vehicle Stability Control).

[0018] The behavior stabilization device 12 controls, for example, the wheel speed V of each wheel. wBased on the output value of the yaw rate sensor and other factors, the yaw moment generated in the base vehicle 100 is detected. The behavior stabilization device 12 then appropriately activates one or more of the friction brakes 11 provided on each wheel in accordance with the yaw moment. In this way, the behavior stabilization device 12 assists the driver in operating the vehicle so that the base vehicle 100 does not fall into dangerous conditions such as oversteer.

[0019] Furthermore, the vehicle stabilization device 12 also controls the torque in the drive shaft 15 (hereinafter referred to as the drive torque) when the friction brake 11 is activated. Specifically, when the friction brake 11 is activated for vehicle stabilization, the vehicle stabilization device 12 reduces the drive torque of the base vehicle 100 to virtually zero, for example, by reducing the engine torque using the ECU 18 or by disengaging the clutch.

[0020] Figure 2 is an explanatory diagram showing the schematic configuration of the vehicle 101 according to this embodiment. As shown in Figure 2, the vehicle 101 is a vehicle in which the driven wheels 17 (rear wheels) of the base vehicle 100 have been replaced with motor-driven wheels 20.

[0021] The motor-driven wheels 20 consist of a battery 21 (BAT), an inverter 22 (INV), and an in-wheel motor 23 (MTR), and are controlled by an MCU 24 (Motor Control Unit). The motor-driven wheels 20 assist in the acceleration and deceleration of the vehicle 101. Specifically, the motor-driven wheels 20 assist in the acceleration of the vehicle 101 by controlling the in-wheel motor 23 to the extent that the battery 21 has power. In addition, the motor-driven wheels 20 assist in the deceleration of the vehicle 101 by regenerating the in-wheel motor 23 to the extent that the battery 21 can accept power. Therefore, the vehicle 101 is a four-wheel drive vehicle, or a semi-four-wheel drive vehicle, composed of the base vehicle 100 and the motor-driven wheels 20. Furthermore, the vehicle 101 is a hybrid vehicle composed of the base vehicle 100 and the motor-driven wheels 20. More simply put, vehicle 101 is a vehicle that has been converted from the base vehicle 100 to a four-wheel drive and hybrid vehicle by adding motor-driven wheels 20.

[0022] Battery 21 is a DC power source that stores the power to drive the in-wheel motor 23. Battery 21 is composed of, for example, a lithium-ion battery and is rechargeable. Battery 21 is charged by the power (regenerative power) generated by the in-wheel motor 23 through regenerative control.

[0023] However, the battery 21 is so small that it is practically integrated with the wheel. Therefore, compared to the large-capacity battery installed in an electric vehicle designed from the outset to be motor-driven, for example, the capacity of the battery 21 in the motor-driven wheel 20 is very small. Consequently, the battery 21 tends to become fully charged (100% charge). When fully charged, the battery 21 can no longer accept regenerative power, so unless power is consumed for acceleration assist or the like, the motor-driven wheel 20 will no longer be able to assist in deceleration. For this reason, in this embodiment, the power of the battery 21 is actively consumed. Hereinafter, the charge rate of the battery 21 will be expressed as SOC (State of Charge), as is commonly used.

[0024] When the inverter 22 is controlling the in-wheel motor 23 to operate, it converts the DC power input from the battery 21 into AC power and supplies it to the in-wheel motor 23. Furthermore, when the inverter 22 is regenerating power from the in-wheel motor 23, it converts the AC regenerative power generated by the in-wheel motor 23 into DC power and supplies it to the battery 21. The inverter 22 is composed of a bridge circuit with multiple switching elements. The operation of the inverter 22 is controlled by so-called PWM (Pulse Width Modulation) control.

[0025] The in-wheel motor 23 is a small motor installed inside the wheel. The in-wheel motor 23 is configured, for example, as a three-phase AC synchronous motor. The in-wheel motor 23 generates power torque by rotating using power from the battery 21. The motor-driven wheel 20 assists in accelerating the vehicle 101 with this power torque. On the other hand, when being driven around by the vehicle 101, the in-wheel motor 23 generates regenerative braking torque. The motor-driven wheel 20 assists in decelerating the vehicle 101 with this regenerative braking torque, converting the kinetic energy of the vehicle 101 into electricity to charge the battery 21. Hereinafter, the driving torque or regenerative braking torque generated by the in-wheel motor 23 in the motor-driven wheel 20 will be collectively referred to as motor torque.

[0026] The MCU24 is a vehicle control device that controls the vehicle 101, and in particular controls the operation of the motor-driven wheels 20. Specifically, the MCU24 assists the acceleration of the vehicle 101 by controlling the motor-driven wheels 20 (in-wheel motors 23) in accordance with the timing of the vehicle 101's acceleration. Also, when the vehicle 101 decelerates, the MCU24 assists the deceleration of the vehicle 101 by controlling the motor-driven wheels 20 (in-wheel motors 23) through regenerative braking. The MCU24 is composed of, for example, one or more computers.

[0027] In addition to the basic assist operation of the motor-driven wheels 20 described above, in this embodiment, the MCU 24 controls the motor-driven wheels 20 and the like for battery management. Specifically, if the State of Charge (SOC) of the battery 21 becomes high and deceleration assistance by the motor-driven wheels 20 becomes impossible or is likely to become impossible, the MCU 24 controls the motor-driven wheels 20 to exert power. This actively consumes power from the battery 21, causing the SOC to decrease.

[0028] Furthermore, when the motor-driven wheels 20 are powered for battery management purposes, the MCU 24 uses the behavior stabilization device 12 to activate one or more of the friction brakes 11 on each wheel, thereby offsetting the motor torque (powering torque) with friction torque. Therefore, even when the MCU 24 powers the motor-driven wheels 20 to reduce the State of Charge (SOC) of the battery 21, the vehicle 101 will not accelerate on its own contrary to the driver's input.

[0029] Furthermore, when the motor-driven wheels 20 are subjected to power control in order to reduce the SOC, the MCU 24 may, via the behavior stabilization device 12, effectively reduce the drive torque of the base vehicle 100 to zero.

[0030] Figure 3 is an explanatory diagram showing a modified configuration of the vehicle 101 according to this embodiment. As shown in Figure 3, the MCU 24 may be provided individually on the left and right motor drive wheels 20. That is, the motor drive wheels 20 may have a configuration that includes the MCU 24 in addition to the battery 21, inverter 22, and in-wheel motor 23. However, even if the MCU 24 is provided individually on each motor drive wheel 20, the entirety of each MCU 24 on each motor drive wheel 20 can be considered as substantially one unit.

[0031] Figure 4 is a block diagram showing the configuration of the MCU 24. For simplicity, we will describe the configuration for controlling one of the left and right motor-driven wheels 20. The configuration for controlling the other motor-driven wheel 20 is similar. However, the MCU 24 controls the left and right motor-driven wheels 20 independently.

[0032] As shown in FIG. 4, MUC24 includes a motor torque setting unit 31, a current control unit 32, a PWM control unit 33, a power consumption control unit 34, and a friction torque control unit 35.

[0033] The motor torque setting unit 31 sets the torque command T m * of the vehicle 101. The torque command T m * represents a target value (command value) for the motor torque generated by the in-wheel motor 23.

[0034] In the present embodiment, the motor torque setting unit 31 sets the torque command T m * based on the vehicle speed V of the vehicle 101. When the vehicle speed V increases, the motor torque setting unit 31 sets a positive torque command T m * (T m * > 0) having a magnitude corresponding to the increase amount of the vehicle speed V. Thereby, the motor drive wheels 20 are subjected to power running control to assist the acceleration of the vehicle 101. When the vehicle speed V decreases, the motor torque setting unit 31 sets a negative torque command T m * (T m * < 0) having a magnitude corresponding to the decrease amount of the vehicle speed V. Thereby, the motor drive wheels 20 are subjected to regeneration control to assist the deceleration of the vehicle 101.

[0035] Also, in the present embodiment, when it is necessary to operate the motor drive wheels 20 to actively consume the power of the battery 21 and reduce the SOC, the motor torque setting unit 31 sets a positive torque command T m * (T m * > 0). Thereby, the motor drive wheels 20 are subjected to power running control. In other words, not only when assisting acceleration, but also when consuming the power of the battery 21, the motor torque setting unit 31 sets a positive torque command T m * .

[0036] In addition, if oversteer or the like is detected and the behavior stabilization device 12 is activated, the motor torque setting unit 31 will set the torque command T m * This setting allows the motor-driven wheels 20 to assist in suppressing or eliminating dangerous behaviors such as oversteer.

[0037] The current control unit 32 controls the torque command T m * Based on the above, the d-axis current command i d * and q-axis current command i q * (Hereinafter, dq axis current command i dq * Set the dq axis current command i (collectively referred to as i). dq * This is the motor torque, which is controlled by the torque command T m * To match or track the current, the d-axis current i should be supplied to the in-wheel motor 23. d and q-axis current i q (Hereafter, dq axis current i dq This represents the target value (command value) for (i). d-axis current i d This is the current component that primarily contributes to the generation of the magnetic field, and the q-axis current i q This is the current component that primarily contributes to the generation of motor torque.

[0038] The current control unit 32, in principle, controls the dq axis current command i by maximum efficiency control such as MTPA (Maximum Torque Per Ampere) control. dq * The current control unit 32 sets the dq axis current command i to produce the maximum motor torque with the minimum current when assisting the acceleration or deceleration of the vehicle 101. dq * Set it.

[0039] However, when the motor drive wheels 20 are operated to actively consume power from the battery 21 and reduce the SOC, the current control unit 32 issues a dq axis current command i at an operating point different from that of MTPA control. dq * This can be set. Specifically, the current control unit 32 sets the d-axis current i to be higher than when MTPA control is performed. d The d-axis current command i increases d * This can be set. In other words, the current control unit 32 may deliberately select an operating point for the in-wheel motor 23 that is less efficient than MTPA control. As a result, the current control unit 32 controls the torque command T by the in-wheel motor 23. m * While outputting motor torque accordingly, the current flowing to the inverter 22 and the in-wheel motor 23 can be increased. As a result, energy losses (so-called copper losses and iron losses) in the inverter 22 and the in-wheel motor 23 increase.

[0040] Furthermore, as mentioned above, even when the motor drive wheels 20 are operated in order to reduce the SOC, the torque command T m * Since it is set to a positive value rather than zero, the q-axis current command i q * (q-axis current i q ) will never be zero.

[0041] The PWM control unit 33 issues a dq axis current command i dq * Accordingly, Duty Directive D * Generates Duty Directive D * This determines the timing for turning the switching elements of the inverter 22 on and off. Duty directive D * The frequency of the carrier wave used to generate the duty cycle command D is predetermined. Specifically, when the motor drive wheels 20 assist in accelerating or decelerating the vehicle 101, the PWM control unit 33 uses a carrier wave having a predetermined frequency (hereinafter referred to as the fundamental frequency) to generate the duty cycle command D * Generates.

[0042] However, when the motor drive wheels 20 are operated to actively consume power from the battery 21 and reduce the SOC, the PWM control unit 33 uses a carrier wave with a frequency higher than the fundamental frequency to execute the duty cycle command D * This can generate a high-frequency carrier wave. In this way, the PWM control unit 33 uses a high-frequency carrier wave, which increases the switching loss in the inverter 22 and accelerates the power consumption of the battery 21.

[0043] The power consumption control unit 34 uses the motor torque setting unit 31 and the friction torque control unit 35 to actively consume power from the battery 21 and perform power consumption control to lower the State of Charge (SOC).

[0044] The power consumption control unit 34 decides whether or not to perform power consumption control based on the State of Charge (SOC) of the battery 21. Specifically, the power consumption control unit 34 decides to perform power consumption control when the SOC is equal to or greater than the threshold Th. The threshold Th is a parameter that determines when the battery 21 is nearly fully charged and there are scenes in which the motor drive wheels 20 cannot assist in deceleration, or scenes in which there is a possibility that deceleration cannot be sufficiently assisted. This parameter is predetermined based on experiments or simulations.

[0045] If power consumption control is decided to be performed, the power consumption control unit 34 will receive a torque command T for power consumption control from the motor torque setting unit 311. m * Set the torque command T for power consumption control. m * The torque command T is at least positive and is set to power the motor drive wheel 20 to rotation. m * This is predetermined based on experiments or simulations, etc. Torque command T for power consumption control m * The specific values ​​are, for example, SOC, vehicle speed V, and wheel speed V. wIt changes depending on the state (straight-line driving / turning), etc. However, in this embodiment, for simplicity, the torque command T for power consumption control is used. m * The value shall be selected from predetermined values.

[0046] When power consumption control is initiated, the power consumption control unit 34 activates the friction brake 11 via the friction torque control unit 35, thereby offsetting the motor torque generated by the power consumption control with friction torque. Therefore, even when power consumption control is initiated, no substantial driving force is generated in the vehicle 101.

[0047] Furthermore, when performing power consumption control, the power consumption control unit 34 controls the d-axis current i by the current control unit 32, which is more efficient than MTPA control. d The d-axis current command i increases d * This is set, or the PWM control unit 33 is made to use a high-frequency carrier wave. This allows the power consumption control unit 34 to further increase the power consumption of the battery 21. Of course, the power consumption control unit 34 controls the d-axis current i d This increases the frequency and allows the PWM control unit 33 to use a high-frequency carrier wave.

[0048] The power consumption control unit 34 performs power consumption control when the vehicle speed V is decreasing, that is, when the vehicle 101 is decelerating. For simplicity, in the following, it will be assumed that the power consumption control unit 34 performs power consumption control when the vehicle 101 is decelerating while the driver is not operating either the accelerator pedal or the brake pedal.

[0049] The power consumption control unit 34 adjusts the specific execution mode of power consumption control depending on whether the vehicle 101 is moving straight or turning. In this embodiment, as an example, the power consumption control unit 34 controls the wheel speeds V of the main drive wheels 16 and motor drive wheels 20. w Based on this, it is determined whether vehicle 101 is moving straight or turning. The speed of the left and right wheels V wWhen there is virtually no difference, the power consumption control unit 34 determines that the vehicle 101 is moving straight. Also, the left and right wheel speeds V w When a substantial difference occurs, the power consumption control unit 34 determines that the vehicle 101 is turning. The power consumption control unit 34 can also determine that the vehicle 101 is turning using steering wheel operation information.

[0050] The power consumption control unit 34 may apply power control to both the left and right motor drive wheels 20 to stabilize the vehicle 101's behavior when it reduces the State of Control (SOC) of one of the left or right motor drive wheels 20. Furthermore, when the power consumption control unit 34 applies power control to both the left and right motor drive wheels 20, it may apply different torque commands T to each of the left and right motor drive wheels 20 to stabilize the vehicle 101's behavior. m * This may require you to configure the settings.

[0051] In addition, the power consumption control unit 34 acquires the operating status of the behavior stabilization device 12. Then, the power consumption control unit 34 adjusts the specific execution mode of power consumption control according to the operating status of the behavior stabilization device 12. That is, the power consumption control unit 34 changes the execution mode of power consumption control depending on whether the vehicle 101 is experiencing oversteer or the like and the behavior stabilization device 12 is operating, or whether the vehicle 101 is running stably and the behavior stabilization device 12 is not operating.

[0052] The friction torque control unit 35 sets the torque command T for power consumption when power consumption control is performed. m *The friction brake 11 is activated so that the resulting motor torque is offset by friction torque. In particular, the friction torque control unit 35 intervenes in the control of the friction brake 11 using the behavior stabilization device 12 that is originally provided in the base vehicle 100. For this reason, the friction torque control unit 35 can individually intervene in the control of the friction brake 11 of each wheel. That is, by operating the friction brake 11 using the behavior stabilization device 12, the friction torque control unit 35 can select and operate one or more of the friction brakes 11 of each wheel.

[0053] For example, the friction torque control unit 35 can activate the friction brake 11 of the motor drive wheel 20 that is subject to power consumption control, i.e., the motor drive wheel 20 that reduces the SOC, in order to counteract the motor torque generated by power consumption control. In addition, the friction torque control unit 35 can activate the friction brake 11 of the main drive wheel 16 on the same side as the motor drive wheel 20 that reduces the SOC, on both the left and right sides of the vehicle 101, in order to counteract the motor torque generated by power consumption control.

[0054] The following describes the operation of power consumption control in vehicle 101 configured as described above.

[0055] Figure 5 is a flowchart relating to the control of the motor-driven wheel 20. Here, an overview of the operation of the motor-driven wheel 20 is shown. In other words, Figure 5 omits practical and complex conditional branching, etc., and shows the basic operation mode of the motor-driven wheel 20.

[0056] As shown in Figure 5, in step S10, the power consumption control unit 34 determines, for example, whether the vehicle 101 is decelerating based on the vehicle speed V.

[0057] When the vehicle 101 is not decelerating (step S10: NO), the process proceeds to step S11, and the motor torque setting unit 31 checks whether the vehicle 101 is accelerating based on the vehicle speed V. If it is determined that the vehicle 101 is accelerating, the process proceeds to step S12, and the motor torque setting unit 31 sets a positive torque command T m * in accordance with the increase amount of the vehicle speed V to perform power running control on the motor drive wheels 20. Thereby, the acceleration of the vehicle 101 is assisted by the motor drive wheels 20. On the other hand, when the vehicle 101 is neither substantially decelerating nor accelerating (step S11: NO), step S12 is skipped. In this case, the motor drive wheels 20 are merely driven wheels.

[0058] In step S10, if it is determined that the vehicle 101 is decelerating, the process proceeds to step S13, and the power consumption control unit 34 compares the SOC of the motor drive wheels 20 with the threshold value Th.

[0059] If the SOC is less than the threshold value Th (step S13: NO), the power consumption control unit 34 decides not to perform power consumption control, and the control proceeds to step S14. In step S14, the motor torque setting unit 31 sets a negative torque command T m * in accordance with the decrease amount of the vehicle speed V to perform regeneration control on the motor drive wheels 20. Thereby, the deceleration of the vehicle 101 is assisted by the motor drive wheels 20.

[0060] On the other hand, if the SOC is greater than or equal to the threshold value Th in step S13, the power consumption control unit 34 decides to perform power consumption control, and the control proceeds to step S15. In step S15, the power consumption control unit 34 sets a positive torque command T m * for the motor torque setting unit 31 to perform power running control on the motor drive wheels 20. Then, in step S16, the friction torque control unit 35 operates the friction brake 11 using the behavior stabilization device 12 so as to cancel out the motor torque generated by the power running control in step S15.

[0061] Thus, in this embodiment, when the SOC is high and the motor-driven wheels 20 cannot sufficiently assist in decelerating the vehicle 101, power consumption control is performed in which the motor-driven wheels 20 are deliberately subjected to power control to consume power from the battery 21, and the motor torque generated by this power consumption control is offset by friction torque.

[0062] Therefore, although the State of Charge (SOC) tends to be high due to the small capacity of the battery 21 of the motor-driven wheels 20, in the vehicle 101 of this embodiment, the situation in which the motor-driven wheels 20 cannot assist in deceleration is automatically resolved. Furthermore, since the vehicle 101 does not generate substantially unnecessary driving force, the SOC can be reduced without impairing the driving feeling that the driver expects.

[0063] Furthermore, in step S15, when the motor drive wheel 20 is powered for power consumption, the power consumption control unit 34 controls the d-axis current i d This increases the value, or raises the frequency of the carrier wave in PWM control. As a result, the power consumption control unit 34 can further promote energy consumption in the inverter 22 and in-wheel motor 23, and reduce the SOC more efficiently.

[0064] Figures 6 and 7 are explanatory diagrams illustrating typical operating patterns of the in-wheel motor 23 and friction brake 11 in power consumption control. Both Figures 6 and 7 show examples of power consumption control being performed when the vehicle 101 is moving straight and decelerating, and the driver is not pressing the brake pedal. Figure 6 shows an example of activating the friction brake 11 of the motor-driven wheel 20 that reduces the SOC. Figure 7 shows an example of activating the friction brake 11 of the main drive wheel 16 on the same side as the motor-driven wheel 20 that reduces the SOC, on both the left and right sides of the vehicle 101. The white arrows in Figures 6 and 7 indicate the direction of travel (straight) of the vehicle 101. In Figures 6 and 7, the in-wheel motor 23 and friction brake 11 that are being operated are indicated by hatching.

[0065] As shown in FIG. 6(A), when the SOC of the motor drive wheel 20 of the left rear wheel becomes equal to or higher than the threshold Th, the motor drive wheel 20 of the left rear wheel is under power running control for power consumption, and the friction brake 11 of the left rear wheel is actuated. For this reason, the motor torque T P1 of the left rear wheel is offset by the friction torque T B1 of the left rear wheel as well. Therefore, the SOC of the motor drive wheel 20 of the left rear wheel can be decreased without substantially affecting the behavior of the vehicle 101.

[0066] Similarly, when the SOC of the motor drive wheel 20 of the right rear wheel becomes equal to or higher than the threshold Th, as shown in FIG. 6(B), the motor drive wheel 20 of the right rear wheel is under power running control for power consumption, and the friction brake 11 of the right rear wheel is actuated. For this reason, the motor torque T P2 of the right rear wheel is offset by the friction torque T B2 of the right rear wheel as well. Therefore, the SOC of the motor drive wheel 20 of the right rear wheel can be decreased without substantially affecting the behavior of the vehicle 101.

[0067] Furthermore, when the SOCs of both the left and right motor drive wheels 20 become equal to or higher than the threshold Th, the situation is the same as above. Specifically, as shown in FIG. 6(C), for power consumption, the motor drive wheels 20 of the right rear wheel and the left rear wheel are under power running control. On the other hand, the friction brakes 11 of the right rear wheel and the left rear wheel are also actuated. For this reason, the motor torque T P1 of the left rear wheel is offset by the friction torque T B1 of the left rear wheel, and the motor torque T P2 of the right rear wheel is offset by the friction torque T B2 of the right rear wheel. Therefore, the SOCs of each of the left and right motor drive wheels 20 can be decreased without substantially affecting the behavior of the vehicle 101.

[0068] In Figure 6, the friction brake 11 of the motor-driven wheel 20, which is controlled for power consumption, is activated, but this is not limited to this. On the left and right sides of the vehicle 101, the friction brake 11 of the main drive wheel 16 on the same side as the motor-driven wheel 20, which is controlled for power consumption, may also be activated.

[0069] For example, as shown in Figure 7(A), when the motor-driven left rear wheel 20 is powered for power consumption, instead of activating the friction brake 11 on the left rear wheel, the friction brake 11 on the main drive left front wheel 16 can be activated. In this case, the motor torque T of the left rear wheel P1 The friction torque T of the left front wheel B1 This is offset by the other factor. Therefore, the SOC can be reduced in the motor-driven left rear wheel 20 with little effect on the behavior of the vehicle 101.

[0070] Similarly, as shown in Figure 7(B), when the motor-driven wheel 20 of the right rear wheel is powered for power consumption, the friction brake 11 on the main drive wheel 16 of the right front wheel can be activated instead of the friction brake 11 on the right rear wheel. In this case, the motor torque T of the right rear wheel P2 The friction torque T of the right front wheel B2 This is offset by the other factor. Therefore, the SOC can be reduced in the motor-driven wheel 20 of the right rear wheel with little effect on the behavior of the vehicle 101.

[0071] The same applies when both the left and right motor-driven wheels 20 are powered. That is, as shown in Figure 7(C), when both the left and right motor-driven wheels 20 are powered for power consumption, instead of activating the friction brakes 11 of each motor-driven wheel 20, the friction brakes 11 provided on the main drive wheels 16 of both the left and right wheels can be activated. In this case, the motor torque T of the left rear wheel P1 The friction torque of the left front wheel is T B1 This cancels out the motor torque of the right rear wheel T P2 The friction torque of the right front wheel is T B2This cancels out the effect. Therefore, the SOC can be reduced in each of the left and right motor-driven wheels 20 with little effect on the behavior of the vehicle 101.

[0072] Figure 8 is a flowchart illustrating the control of the motor-driven wheels 20 when the vehicle 101 is turning. Here, the in-wheel motor 23 of the inner motor-driven wheel 20 is called the inner motor, and the in-wheel motor 23 of the outer motor-driven wheel 20 is called the outer motor. Furthermore, of the left and right motor-driven wheels 20, the state of charge (SOC) of the battery 21 of the inner motor-driven wheel 20 is called the inner SOC, and the SOC of the battery 21 of the outer motor-driven wheel 20 is called the outer SOC. Here, it is assumed that the vehicle 101 is decelerating. In other words, the flowchart shown in Figure 8 illustrates the details of steps S13 to S16 in Figure 5 for a scene in which the vehicle 101 is turning.

[0073] As shown in Figure 8, in step S21, the power consumption control unit 34 checks whether the behavior stabilization device 12 is activated due to oversteer. If the behavior stabilization device 12 is activated, the process proceeds to step S22, where the motor torque setting unit 31 controls the inner ring motor to eliminate the oversteer.

[0074] In step S23, the power consumption control unit 34 compares the outer ring SOC with a threshold Th. If the outer ring SOC is greater than or equal to the threshold Th in step S23, the power consumption control unit 34 decides to perform power consumption control on the motor drive wheels 20 of the outer ring, and the control proceeds to step S24.

[0075] In step S24, the power consumption control unit 34 issues a torque command T, which is positive and smaller than the motor torque generated by the inner ring motor, via the motor torque setting unit 31. m *By setting this, the motor-driven outer wheel 20 is subjected to power control. That is, the motor-driven outer wheel 20 is subjected to power control within the range in which the motor-driven inner wheel 20 assists in behavior stabilization. Then, in step S25, the friction torque control unit 35 uses the behavior stabilization device 12 to activate the friction brake 11 in order to counteract the motor torque generated by the power control in step S24. At this time, the friction torque control unit 35, in principle, activates a friction brake 11 other than the friction brake 11 that the behavior stabilization device 12 is activating to eliminate oversteer.

[0076] Furthermore, if the outer ring SOC is smaller than the threshold Th in step S23, the power consumption control unit 34 determines that it is not necessary to control the power consumption of the outer ring motor drive wheel 20. Therefore, steps S24 and S25 are skipped.

[0077] If it is confirmed in step S21 that the behavior stabilization device 12 is not operating, the control proceeds to step S26. In step S26, the power consumption control unit 34 compares the inner ring SOC with a threshold Th. If the inner ring SOC is greater than or equal to the threshold Th, the power consumption control unit 34 decides to perform power consumption control for the inner ring motor drive wheel 20. Therefore, in step S27, the power consumption control unit 34 receives a positive torque command T from the motor torque setting unit 31. m * By setting this, the inner ring motor is controlled to perform power. Then, in step S28, the friction brake 11 is activated to counteract the motor torque generated by the power control in step S27. Note that in step S26, if the inner ring SOC is smaller than the threshold Th and there is no need to reduce the inner ring SOC, steps S27 and S26 are skipped.

[0078] In step S29, the power consumption control unit 34 compares the outer ring SOC with a threshold Th. If the outer ring SOC is greater than or equal to the threshold Th, the power consumption control unit 34 decides to perform power consumption control for the motor drive wheel 20 of the outer ring. Therefore, in step S30, the power consumption control unit 34 receives a positive torque command T from the motor torque setting unit 31. m * By setting this, the outer ring motor is controlled to perform power. Then, in step S31, the friction brake 11 is activated to counteract the motor torque generated by the power control in step S30. Note that in step S29, if the outer ring SOC is smaller than the threshold Th and there is no need to reduce the outer ring SOC, steps S30 and S31 are skipped.

[0079] In step S32, the power consumption control unit 34 checks whether both the inner ring SOC and the outer ring SOC are smaller than the threshold Th. If both the inner ring SOC and the outer ring SOC are smaller than the threshold Th, the control proceeds to step S33, and the motor torque setting unit 31 appropriately controls the regenerative braking of the inner motor drive wheel 20, the outer motor drive wheel 20, or both, to assist in the deceleration of the vehicle 101.

[0080] Furthermore, in step S30, if both the inner and outer ring motors are powered by powering the outer ring motor, the motor torque of the outer ring motor should be smaller than the motor torque of the inner ring motor, according to each torque command T. m * This is adjusted. As a result, oversteer is reliably prevented even when power consumption control is performed for both the inner and outer motor-driven wheels 20.

[0081] Furthermore, from the perspective of reliably preventing oversteer during turns, power consumption control for the outer motor-driven wheels 20 may be performed only when power consumption control for the inner motor-driven wheels 20 is also performed, thus excluding operation patterns in which only the outer motors are powered. This can be achieved, for example, by skipping steps S27 to S31 if the inner ring SOC is smaller than the threshold Th in step S26.

[0082] Figure 9 is an explanatory diagram showing a typical operating pattern of the in-wheel motor 23 and friction brake 11 when the motion stabilization device 12 is activated during a turn. The white arrows indicate the direction of travel of the vehicle 101. Here, it is assumed that the vehicle 101 is turning to the left.

[0083] As shown in Figure 9, when oversteer is detected while the vehicle 101 is turning to the left, the vehicle stabilization device 12 activates the friction brake 11, for example, on the main drive wheel 16 of the right front wheel, to eliminate the oversteer, thereby applying friction torque T B This generates '. At this time, the motor-driven wheel 20 of the inner wheel (left rear wheel) is powered, and the inner wheel motor generates motor torque T P1 This causes the motor torque T P1 This generates a clockwise yaw moment in the vehicle 101. As a result, the motor-driven inner wheel 20 assists in eliminating oversteer.

[0084] Even under these circumstances, if the State of Charge (SOC) of the battery 21 of the motor-driven wheel 20 of the outer wheel (right rear wheel) is greater than or equal to the threshold Th, power consumption control is performed for the motor-driven wheel 20 of the outer wheel. That is, the vehicle 101 controls the power of the outer wheel motor and, for example, activates the friction brake 11 provided on the motor-driven wheel 20 of the outer wheel. As a result, the power of the battery 21 of the motor-driven wheel 20 of the outer wheel is consumed, and the motor torque T generated by the outer wheel motor is also consumed. P2 friction torque T B2 This is offset by the other factor. Therefore, vehicle 101 can reduce the outer wheel SOC while eliminating oversteer.

[0085] Also, the motor torque T of the outer ring motor P2 This generates a counterclockwise yaw moment, but the motor torque T of the outer ring motor P2 The motor torque T of the inner ring motor P1 It is adjusted to a value smaller than this. Therefore, the friction torque T B2 Even if there is a delay in the occurrence of the motor torque T of the outer ring motor, P2 This does not exacerbate oversteer.

[0086] Figure 10 is an explanatory diagram showing a typical operating pattern of the in-wheel motor 23 and friction brake 11 when the motion stabilization device 12 is not activated during turning. The white arrows indicate the direction of travel of the vehicle 101. Here, it is assumed that the vehicle 101 is turning to the left.

[0087] As shown in Figure 10, if the vehicle 101 is turning stably to the left without oversteer, the behavior stabilization device 12 does not operate. Under these circumstances, when the State of Charge (SOC) of the inner wheel (left rear wheel), outer wheel (right rear wheel), or both of these motor-driven wheels 20 exceeds the threshold Th, power consumption control is performed for the motor-driven wheel 20 whose SOC exceeds the threshold Th.

[0088] For example, when the inner ring SOC is greater than or equal to the threshold Th, the inner ring motor is powered. The motor torque T generated by the inner ring motor is then applied. P1 To counteract this, for example, a friction brake 11 provided on the main drive wheel 16 of the left front wheel is activated. This causes the motor torque T of the inner ring motor to be activated. P1 The friction torque T of the left front wheel B1 This is offset by the other factor. Therefore, the inner wheel SOC can be reduced with little effect on the behavior of vehicle 101.

[0089] Furthermore, when the outer ring SOC is greater than or equal to the threshold Th, the outer ring motor is subjected to power control. The motor torque T generated by the outer ring motor is then... P2To counteract this, for example, a friction brake 11 provided on the main drive wheel 16 of the right front wheel is activated. This causes the motor torque T of the outer wheel motor to be activated. P2 The friction torque T of the right front wheel B2 This is offset by the other factor. Therefore, the outer wheel SOC can be reduced with little effect on the behavior of vehicle 101.

[0090] When both the inner ring SOC and the outer ring SOC are above the threshold Th, the inner ring motor and the outer ring motor are powered. The motor torque T generated by the inner ring motor is then applied. P1 To counteract this, for example, a friction brake 11 provided on the left front main drive wheel 16 is activated, and the motor torque T generated by the outer wheel motor is also activated. P2 To counteract this, for example, a friction brake 11 provided on the main drive wheel 16 of the right front wheel is activated. This causes the motor torque T of the inner ring motor to be activated. P1 The friction torque of the left front wheel is T B1 This is offset by the motor torque T of the outer ring motor. P2 The friction torque T of the front wheels B2 This cancels out the effect. Therefore, the inner and outer wheel SOC can be reduced with little effect on the behavior of the vehicle 101.

[0091] Furthermore, when both the inner and outer ring motors are powered in this manner, the motor torque T of the outer ring motor... P2 The motor torque T of the inner ring motor P1 It is adjusted to be smaller than Friction Torque T B1 ,T B2 Even if there is a delay in the generation of the motor torque T P1 ,T P2 This does not exacerbate oversteer.

[0092] In Figure 10, the motor torque T is increased by activating the friction brake 11 of the main drive wheel 16. P1 ,T P2 This cancels out, but is not limited to this. Motor torque T of the inner ring motor. P1To counteract this, the friction brake 11 provided on the inner motor drive wheel 20 may be activated. Similarly, the motor torque T of the outer ring motor P2 To counteract this, the friction brake 11 provided on the motor-driven wheel 20 of the outer ring may be activated.

[0093] In addition, when performing the power consumption control of the above embodiment, the MCU 24, in principle, controls the base vehicle 100 so that the driving torque becomes substantially zero via the behavior stabilization device 12. At least when the friction brake 11 of a wheel (main drive wheel 16) different from the motor drive wheel 20 that is powered in the power consumption control is activated, or when the vehicle 101 is turning, the MCU 24 controls the base vehicle 100 so that the driving torque becomes substantially zero. This is to ensure the behavioral stability of the vehicle 101 by particularly accurately canceling out the motor torque and friction torque in the power consumption control.

[0094] As described above, the vehicle control method according to the above embodiment is a vehicle control method for controlling a vehicle 101 in which the driven wheels 17 of a base vehicle 100 having a behavior stabilization device 12 using friction brakes 11 have been replaced with motor-driven wheels 20 configured using a battery 21, an inverter 22, and an in-wheel motor 23. In this vehicle control method, when the state of charge (SOC) of the battery 21 is above a predetermined threshold Th, the motor-driven wheels 20 are subjected to power control, and the friction brakes 11 are activated using the behavior stabilization device 12, thereby offsetting the motor torque generated by the motor-driven wheels 20 during power control with the friction torque generated by the friction brakes 11.

[0095] In this way, by controlling the motor drive wheels 20 and performing power consumption control that offsets the resulting motor torque with friction torque generated by the behavior stabilization device 12, it is possible to promote power consumption of the motor drive wheels 20, which tend to be fully charged with a small capacity, with little effect on the behavior of the vehicle 101. As a result, the motor drive wheels 20 can be used to continuously assist in the deceleration of the vehicle 101.

[0096] In the vehicle control method according to the above embodiment, if the state of charge (SOC) of the battery 21 is greater than or equal to a threshold Th in one of the two motor-driven wheels 20, only the motor-driven wheel 20 whose SOC is greater than or equal to the threshold Th is subjected to power control.

[0097] Thus, when the State of Charge (SOC) of one of the motor-driven wheels 20 reaches a threshold Th, power consumption control can be performed for that motor-driven wheel 20. In other words, the power consumption control according to the above embodiment can usually be performed for each motor-driven wheel 20. Therefore, the SOC can be easily adjusted.

[0098] In the vehicle control method according to the above embodiment, if the state of charge (SOC) of the battery 21 is greater than or equal to a threshold Th for both motor-driven wheels 20, both motor-driven wheels 20 are subjected to power control.

[0099] In this way, when the State of Charge (SOC) of both motor-driven wheels 20 exceeds the threshold Th, power consumption control can be performed for both motor-driven wheels 20 substantially simultaneously. Therefore, the SOC can be easily adjusted.

[0100] In the vehicle control method according to the above embodiment, the motor torque is offset by activating the friction brake 11 of the motor-driven wheel 20 that is controlled to exert power.

[0101] In this way, by activating the friction brake 11 provided on the motor-driven wheel 20, which controls power consumption, and offsetting the motor torque with friction torque in the motor-driven wheel 20, it is particularly easy to reliably cancel out the motor torque generated for power consumption.

[0102] In the vehicle control method according to the above embodiment, the motor torque is offset by activating the friction brake 11 of the main drive wheel 16, which is the drive wheel of the base vehicle 100.

[0103] In this way, the friction brake 11 of the main drive wheel 16 can be activated to offset the motor torque generated for power consumption with the friction torque of the main drive wheel 16. Depending on the specific configuration of the vehicle 101 and the actual driving scenario, activating the friction brake 11 of the main drive wheel 16 as described above may be more reliable in ensuring the vehicle 101's behavioral stability than activating the friction brake 11 of the motor drive wheel 20, which is used for power control to consume power.

[0104] In the vehicle control method according to the above embodiment, the friction brake 11 of the main drive wheel 16 on the same side (for example, the right side) as the motor drive wheel 20 that is to be powered (for example, the right side) on the left and right sides of the vehicle 101 is activated.

[0105] In this way, when the friction brake 11 of the main drive wheel 16, which is on the same side as the motor drive wheel 20 that is controlled for power consumption, is applied, no yaw moment is generated in the vehicle 101. Therefore, even when the friction brake 11 of the main drive wheel 16 is applied during power consumption control, power consumption control can be performed while maintaining the stable behavior of the vehicle 101.

[0106] In the vehicle control method according to the above embodiment, when the motor-driven wheels 20 are subjected to power control or regenerative control to assist in the acceleration or deceleration of the vehicle 101, the inverter 22 is driven using a carrier wave having a predetermined fundamental frequency. Furthermore, when the motor-driven wheels 20 are subjected to power control because the state of charge (SOC) of the battery 21 is above a threshold Th, the inverter 22 is driven using a carrier wave having a frequency higher than the fundamental frequency.

[0107] Thus, when performing power consumption control, using a high-frequency carrier wave in the PWM control of the inverter 22 increases the switching loss in the inverter 22. Therefore, the SOC of the motor drive wheels 20 can be reduced more efficiently.

[0108] In the vehicle control method according to the above embodiment, when the motor drive wheel 20 is powered because the charge level (SOC) of the battery 21 is above a threshold Th, the d-axis current i is compared to the maximum efficiency control. d Increase.

[0109] Thus, when power consumption control is performed, the d-axis current i of the in-wheel motor 23 d Increasing this increases energy loss in the inverter 22 and the in-wheel motor 23. Therefore, the SOC of the motor-driven wheel 20 can be reduced more efficiently.

[0110] In the vehicle control method according to the above embodiment, when the state of charge (SOC) of the battery 21 is greater than or equal to a threshold Th, the motor-driven wheels 20 are powered and the friction brakes 11 are activated using the behavior stabilization device 12 when the vehicle 101 is decelerating.

[0111] Thus, it is preferable to perform power consumption control when the vehicle 101 is decelerating. This is because, when the vehicle 101 is decelerating, it is not affected by the driving torque of the base vehicle 100, making it easier to stabilize the behavior of the vehicle 101, even when power consumption control is performed.

[0112] In the vehicle control method according to the above embodiment, when the state of charge (SOC) of the battery 21 is equal to or greater than a threshold Th, the motor-driven wheels 20 are powered and the friction brakes 11 are activated when the vehicle 101 is moving in a straight line.

[0113] Thus, it is particularly preferable to perform power consumption control when the vehicle 101 is moving substantially in a straight line. This is because when the vehicle 101 is moving in a straight line and no yaw moment is generated, it is easier to stabilize the behavior of the vehicle 101 in terms of power consumption control.

[0114] In the vehicle control method according to the above embodiment, when the vehicle 101 is turning and both the inner and outer motor-driven wheels 20 are subjected to power control, the motor torque of the outer wheel is adjusted to be smaller than the motor torque of the inner wheel.

[0115] Thus, when controlling power consumption while the vehicle 101 is turning, adjusting the motor torque of the outer ring to be smaller than the motor torque of the inner ring ensures that the vehicle 101 does not oversteer, even if there is a delay in the generation of friction torque.

[0116] In the vehicle control method according to the above embodiment, when the vehicle 101 is turning and the behavior stabilization device 12 is activated due to oversteer, when the motor-driven outer wheel 20 is subjected to power control, the friction brake 11 provided on the motor-driven outer wheel 20 is activated to assist in eliminating the oversteer with the motor torque of the inner wheel and to counteract the motor torque of the outer wheel.

[0117] Thus, even when the vehicle 101 is turning and the behavior stabilization device 12 is activated due to oversteer, power consumption control can be performed for the motor-driven outer wheels 20 while assisting in the elimination of oversteer.

[0118] In the vehicle control method according to the above embodiment, when the friction brake 11 of a wheel (main drive wheel 16) different from the motor-driven wheel 20 that is being powered is activated, or when the vehicle 101 is turning, the drive torque of the base vehicle 100 is set to zero.

[0119] Thus, when controlling power consumption, limiting the drive torque of the base vehicle 100 (torque or driving force from the engine 10) to virtually zero makes it easier to stabilize the behavior of the vehicle 101. Furthermore, as described above, it is easier to ensure the stability of the vehicle 101's behavior even when the motor torque generated by power consumption control is offset by the friction torque of the main drive wheels 16, or when the vehicle 101 is turning.

[0120] The vehicle control device according to the above embodiment is a vehicle control device (MCU24) that controls a vehicle 101 in which the driven wheels 17 of a base vehicle 100 having a behavior stabilization device 12 using friction brakes 11 have been replaced with motor-driven wheels 20 configured using a battery 21, an inverter 22, and an in-wheel motor 23. When the state of charge (SOC) of the battery 21 is above a predetermined threshold Th, this vehicle control device (24) controls the motor-driven wheels 20 to perform power control and activates the friction brakes 11 using the behavior stabilization device 12, thereby offsetting the motor torque generated by the motor-driven wheels 20 during power control with the friction torque generated by the friction brakes 11.

[0121] In this way, by controlling the motor drive wheels 20 and performing power consumption control that offsets the resulting motor torque with friction torque generated by the behavior stabilization device 12, it is possible to promote power consumption of the motor drive wheels 20, which tend to be fully charged with a small capacity, with little effect on the behavior of the vehicle 101. As a result, the motor drive wheels 20 can be used to continuously assist in the deceleration of the vehicle 101.

[0122] Although embodiments of the present invention have been described above, the configurations described in the above embodiments represent only a part of the application examples of the present invention and are not intended to limit the technical scope of the present invention.

[0123] For example, in the above embodiment, the base vehicle 100 is an engine-powered vehicle, but it is not limited to this. Even if the base vehicle 100 is an electric vehicle, the power consumption control of the above embodiment is effective if the replaced motor-driven wheels 20 are driven within the range of the battery 21 of the motor-driven wheels 20, without using the battery originally provided by the base vehicle 100. Also, in the above embodiment, the base vehicle 100 is a front-wheel drive vehicle, but the base vehicle 100 may be a rear-wheel drive vehicle. [Explanation of Symbols]

[0124] 10: Engine, 11: Friction brake, 12: Stabilization device, 13: Reducer, 14: Differential gear, 15: Drive shaft, 16: Main drive wheel, 17: Driven wheel, 18: ECU, 20: Motor drive wheel, 21: Battery, 22: Inverter, 23: In-wheel motor, 31: Motor torque setting unit, 32: Current control unit, 33: PWM control unit, 34: Power consumption control unit, 35: Friction torque control unit, 100: Base vehicle, 101: Vehicle, 311: Motor torque setting unit

Claims

1. A vehicle control method for controlling a vehicle in which the driven wheels of a base vehicle having a behavior stabilization device using friction brakes have been replaced with motor-driven wheels configured using a battery, inverter, and in-wheel motors, If the charge level of the aforementioned battery is above a predetermined threshold, The motor-driven wheel is controlled to exert power, and By using the aforementioned behavior stabilization device to activate the friction brake, the motor torque generated by the motor-driven wheel in the power control is offset by the friction torque generated by the friction brake. Vehicle control method.

2. A vehicle control method according to claim 1, If the battery charge level of one of the two motor-driven wheels is above the threshold, then power control is performed only on the motor-driven wheel whose battery charge level is above the threshold. Vehicle control method.

3. A vehicle control method according to claim 1, If the battery charge level in both of the two motor-driven wheels is above the threshold, both motor-driven wheels are subjected to power control. Vehicle control method.

4. A vehicle control method according to claim 1, By activating the friction brake of the motor-driven wheel that controls the power, the motor torque is offset. Vehicle control method.

5. A vehicle control method according to claim 1, The motor torque is offset by activating the friction brakes on the main drive wheels, which are the drive wheels of the base vehicle. Vehicle control method.

6. A vehicle control method according to claim 5, On the left and right sides of the vehicle, the friction brake of the main drive wheel on the same side as the motor-driven wheel that controls the power is activated. Vehicle control method.

7. A vehicle control method according to claim 1, When the motor-driven wheels are subjected to power control or regenerative control to assist in the acceleration or deceleration of the vehicle, the inverter is driven using a carrier wave having a predetermined fundamental frequency. When the motor drive wheel is powered because the battery charge level is above the threshold, the inverter is driven using the carrier wave having a frequency higher than the fundamental frequency. Vehicle control method.

8. A vehicle control method according to claim 1, When the motor drive wheel is powered because the battery charge level is above the threshold, the d-axis current is increased compared to maximum efficiency control. Vehicle control method.

9. A vehicle control method according to claim 1, When the battery charge level is above the threshold, the motor-driven wheels are powered while the vehicle is decelerating, and the friction brakes are activated using the vehicle stabilization device. Vehicle control method.

10. A vehicle control method according to claim 1, When the battery charge level is above the threshold, the motor-driven wheels are powered and the friction brakes are activated while the vehicle is moving straight. Vehicle control method.

11. A vehicle control method according to claim 1, When the vehicle is turning, if both the inner and outer motor-driven wheels are subjected to power control, the motor torque of the outer wheel is adjusted to be less than the motor torque of the inner wheel. Vehicle control method.

12. A vehicle control method according to claim 11, When the vehicle is turning and the vehicle stabilization device is activated due to oversteer, the motor-driven outer wheel is subjected to power control. The motor torque of the inner ring assists in eliminating the oversteer. The friction brake provided on the motor drive wheel of the outer ring is activated to counteract the motor torque of the outer ring. Vehicle control method.

13. A vehicle control method according to claim 1, When the friction brakes on wheels other than the motor-driven wheels that are being powered are activated, or when the vehicle is turning, the drive torque of the base vehicle is set to zero. Vehicle control method.

14. A vehicle control device for controlling a vehicle in which the driven wheels of a base vehicle having a behavior stabilization device using friction brakes have been replaced with motor-driven wheels configured using a battery, inverter, and in-wheel motors, If the charge level of the aforementioned battery is above a predetermined threshold, The motor-driven wheel is controlled to exert power, and By using the aforementioned behavior stabilization device to activate the friction brake, the motor torque generated by the motor-driven wheel in the power control is offset by the friction torque generated by the friction brake. Vehicle control system.

Images