Electric vehicle control method and electric vehicle control device

Abstract

An embodiment of the present invention is an electric vehicle control method for performing posture control for controlling a posture in the front and rear direction by adjusting the drive force allocation of front and rear wheels that are drive wheels. This electric vehicle control method detects a basic posture that is the actual posture in the front and rear direction when an electric vehicle stops. A posture control drive force allocation is also calculated that is the drive force allocation for controlling a posture in the front and rear direction when the electric vehicle is accelerated or decelerated. A corrected drive force allocation is then calculated by correcting the posture control drive force allocation on the basis of the basic posture, and the drive wheels are controlled with this corrected drive force allocation.

Description

Control method for electric vehicle and control device for electric vehicle

[0001] The present invention relates to a control method for an electric vehicle and a control device for an electric vehicle.

[0002] JP4876534B2 discloses a technique for reducing the pitch rate of an in-wheel motor vehicle, which does not fully utilize the effects of a suspension, when the vehicle passes over a bump or other obstacle in the road surface. More specifically, it discloses that different braking / driving forces are applied to the front and rear wheels, and when a pitch rate fluctuation is detected, different braking / driving forces are further applied to the left and right wheels at a predetermined cycle.

[0003] Conventionally, electric vehicles are known that perform attitude control by adjusting the distribution of drive force to multiple drive wheels. However, conventional attitude control methods sometimes fail to accurately control the attitude of the electric vehicle to a target attitude.

[0004] For example, if there is a change in the specific usage conditions of the electric vehicle, such as the number of occupants, the specific riding positions, or the amount of luggage in the trunk, the base point (center of gravity) for attitude change during acceleration or deceleration will change. Conventional attitude control controls the attitude of the electric vehicle based on the state of the electric vehicle at the time of manufacture, for example, and therefore, when there is a change in the specific usage conditions of the electric vehicle, as described above, an error occurs due to this, and the attitude of the electric vehicle may not accurately converge to the target attitude.

[0005] Therefore, an object of the present invention is to provide a control method for an electric vehicle and a control device for an electric vehicle that can cause the attitude of the electric vehicle to converge to a target attitude when accelerating or decelerating, regardless of the specific usage situation of the electric vehicle.

[0006] One aspect of the present invention is a control method for an electric vehicle that performs attitude control to control the longitudinal attitude by adjusting the drive force distribution to the front and rear drive wheels. In this control method for an electric vehicle, a basic attitude, which is the actual longitudinal attitude of the electric vehicle when stopped, is detected. Furthermore, when the electric vehicle accelerates or decelerates, a drive force distribution for attitude control, which is a drive force distribution for controlling the longitudinal attitude, is calculated. Then, a corrected drive force distribution is calculated by correcting the drive force distribution for attitude control based on the basic attitude, and the drive wheels are controlled using this corrected drive force distribution.

[0007] FIG. 1 is an explanatory diagram showing a schematic configuration of an electric vehicle. FIG. 2 is an explanatory diagram showing a schematic structure of a chassis system. FIG. 3 is an explanatory diagram showing the attitude of an electric vehicle and changes therein. FIG. 4 is a block diagram showing the configuration of a controller for attitude control. FIG. 5 is a block diagram showing the configuration of a attitude control calculation unit. FIG. 6 is a flowchart showing the operation related to attitude control of an electric vehicle. FIG. 7 is a block diagram showing the configuration of a attitude control calculation unit in a second embodiment. FIG. 8 is a graph showing an example of the relationship between the difference between the front vehicle height and the rear vehicle height and the correction coefficient. FIG. 9 is a flowchart showing the operation related to attitude control in the second embodiment.

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0009] [First embodiment] <Configuration of electric vehicle> Fig. 1 is an explanatory diagram showing a schematic configuration of an electric vehicle 100. The electric vehicle 100 is, for example, an electric vehicle or a hybrid vehicle, and is a vehicle that can drive or brake one or more drive wheels using an electric motor. In particular, in this embodiment, the electric vehicle 100 is a so-called four-wheel drive (4WD) vehicle, and can control (adjust) the drive force generated in each of the multiple drive wheels. Specifically, as shown in Fig. 1, the electric vehicle 100 includes a front-wheel drive system 10, a rear-wheel drive system 11, and a controller 12.

[0010] The front-wheel drive system 10 is a system that controls front wheels 21, which are first drive wheels. The front-wheel drive system 10 includes a front inverter 22 and a front motor 23.

[0011] The front inverter 22 converts DC power output by a battery (not shown) into AC power and supplies it to the front motor 23, thereby driving the front motor 23. When the front motor 23 is rotated by the front wheels 21, the front inverter 22 converts regenerated AC power generated by the front motor 23 into DC power and inputs it to the battery, thereby charging the battery.

[0012] The front motor 23 is an electric motor that drives the front wheels 21. The front motor 23 is, for example, a three-phase AC synchronous motor. The torque generated by the front motor 23 is transmitted to the front wheels 21 via a front drive shaft 24, and a driving force (hereinafter referred to as a front wheel driving force F) is applied to the front wheels 21. Ｆ This generates a phenomenon called

[0013] The rear-wheel drive system 11 is a system that controls rear wheels 26, which are second drive wheels. The rear-wheel drive system 11 includes a rear inverter 27 and a rear motor 28.

[0014] The rear inverter 27 converts DC power output by the battery into AC power and supplies it to the rear motor 28, thereby driving the rear motor 28. Furthermore, when the rear motor 28 is rotated along with the rear wheels 26, the rear inverter 27 converts regenerated AC power generated by the rear motor 28 into DC power and inputs it to the battery, thereby charging the battery.

[0015] The rear motor 28 is an electric motor that drives the rear wheels 26. The rear motor 28 is configured, for example, by a three-phase AC synchronous motor similar to the front motor 23. The torque generated by the rear motor 28 is transmitted to the rear wheels 26 via a rear drive shaft 29, and a driving force (hereinafter referred to as rear wheel driving force F) is applied to the rear wheels 26. Ｒ This generates a phenomenon called

[0016] The controller 12 is configured with one or more computers that control the operation of the electric vehicle 100. The controller 12 is programmed to control the operation of the electric vehicle 100 at a predetermined control cycle. In this embodiment, the controller 12 is a control device for the electric vehicle 100 that performs attitude control to control the attitude in the longitudinal direction by adjusting the distribution of driving force between the front wheels 21 and the rear wheels 26, which are the driving wheels.

[0017] The controller 12 distributes the driving force (hereinafter referred to as total driving force TQ) requested by, for example, operating an accelerator pedal (not shown) to the front wheels 21 and rear wheels 26, which are the driving wheels. Then, the controller 12 calculates the front wheel driving force F according to the distribution. Ｆ and rear wheel driving force F Ｒ The front wheels 21 and the rear wheels 26 are driven by the front-wheel drive system 10 and the rear-wheel drive system 11, respectively, so that the following occurs: Furthermore, in this embodiment, the controller 12 is programmed to execute attitude control that controls the attitude of the electric vehicle 100 in the longitudinal direction by adjusting the distribution of driving force between the front wheels 21 and the rear wheels 26 as necessary.

[0018] When controlling the operation of the electric vehicle 100, the controller 12 can appropriately acquire various parameters that represent the operating state of the electric vehicle 100 by sensors (not shown) or by calculation. ＰＯ Therefore, the controller 12 detects the accelerator opening A ＰＯ The accelerator opening A can be obtained as needed. ＰＯ is a parameter that indicates the amount of accelerator pedal operation. The controller 12 also appropriately acquires the vehicle speed VSP of the electric vehicle 100 from a sensor (not shown) or by calculation.

[0019] In addition, in this embodiment, the electric vehicle 100 is provided with sensors (not shown) (for example, buckle sensors for each seat belt) that detect the fastened / unfastened state of the seat belts provided in the driver's seat, the passenger seat, and the rear seats. For this reason, the controller 12 generates a signal indicating the fastened / unfastened state of the seat belts of each seat (hereinafter referred to as a seat belt fastening / unfastening signal S ｓｅａｔ The electric vehicle 100 also includes a sensor (so-called suspension stroke sensor) that detects the stroke amount of a front suspension 31 (see FIG. 2) provided on the front wheel 21 and a rear suspension 32 (see FIG. 2) provided on the rear wheel 26. For this reason, the controller 12 generates a signal (hereinafter referred to as a suspension stroke signal S) that indicates the stroke amount of each suspension. ｓｕｓ (hereinafter referred to as "information") can be obtained as appropriate.

[0020] Furthermore, in this embodiment, the electric vehicle 100 has a pitch angle θ Ｐ Alternatively, the controller 12 may include a pitch sensor for detecting the pitch rate. Ｐ The controller 12 can also acquire the current location of the electric vehicle 100 and the gradient of the road on which the electric vehicle 100 is traveling (hereinafter referred to as the road gradient φ ＬＳ The road surface gradient φ ＬＳ can be obtained by calculation based on the vehicle speed VSP and acceleration G of the electric vehicle 100, or changes therein.

[0021] <Principle of attitude control by driving force distribution> Fig. 2 is an explanatory diagram showing the schematic structure of the chassis system. As shown in Fig. 2, the front wheels 21 are connected to a vehicle shed 101, which is the part of the vehicle body where the passenger compartment and the like are formed, via a front suspension 31. Similarly, the rear wheels 26 are connected to the vehicle shed 101 via a rear suspension 32.

[0022] For example, the front wheel driving force F Ｆ , rear wheel driving force F ＲWhen the electric vehicle 100 accelerates due to the acceleration of the electric vehicle 100 caused by the acceleration of the electric vehicle 100, the load moves rearward (negative side in the X direction) of the electric vehicle 100. As a result, the center of gravity O Ｇ With pitch angle θ as the center Ｐ Therefore, when the electric vehicle 100 accelerates, the electric vehicle 100 assumes a posture in which the front portion, which is the portion on the positive side in the X direction, is lifted up (a so-called nose-up posture).

[0023] On the other hand, the front wheel driving force F Ｆ The torque of the front motor 23 (hereinafter referred to as "front torque") that generates acts on the vehicle shed 101 via the front suspension 31. Specifically, the front torque is generated by the rotation of the vehicle shed 101 relative to the virtual center of rotation O. Ｆ Around the pitch angle θ Ｐ In other words, when the electric vehicle 100 accelerates, the front torque suppresses nose-up. Similarly, the rear wheel driving force F Ｒ The torque of the rear motor 28 (hereinafter referred to as rear torque) that generates the virtual rotation center O Ｒ Around the pitch angle θ Ｐ Therefore, when the electric vehicle 100 accelerates, the rear torque suppresses nose-up.

[0024] The magnitude of the front torque's effect of suppressing nose-up during acceleration depends on the anti-skid angle θ Ｆ Similarly, the magnitude of the rear torque's effect of suppressing nose-up during acceleration depends on the anti-skid angle θ Ｒ Therefore, if the drive force distribution to the front wheels 21 and the rear wheels 26 is adjusted so that the distribution to the drive wheels with relatively large anti-skid angles is increased, the effect of suppressing nose-up while maintaining the total drive force is increased. Therefore, in this embodiment, the controller 12 adjusts the drive force distribution to the front wheels 21 and the rear wheels 26 to adjust the longitudinal attitude of the electric vehicle 100 (i.e., the pitch angle θ ＰThe system performs attitude control to control the speed of the vehicle (or its fluctuations).

[0025] In addition, the virtual rotation center O Ｆ is an instantaneous and virtual center of rotation that occurs in the vehicle body (particularly the vehicle shed 101) due to the transmission of front torque, and is determined in advance by the specific configuration of the front suspension 31, etc. Similarly, the virtual center of rotation O Ｒ is the instantaneous and virtual center of rotation of the vehicle body (particularly the vehicle shed 101) caused by the transmission of rear torque, and is determined in advance by the specific configuration of the rear suspension 32, etc. Ｆ is the distance between the center of rotation of the front wheel 21 and the virtual center of rotation O on the XZ plane. Ｆ The angle between the line connecting the two points and a line parallel to the road surface is the angle. Ｒ is the distance between the rotation center of the rear wheel 26 and the virtual rotation center O on the XZ plane. Ｒ It is the angle between the line connecting the two and a line parallel to the road surface.

[0026] In this embodiment, as shown in FIG. 2, the anti-scatter angle θ of the rear suspension 32 Ｒ is the anti-skid angle θ of the front suspension 31 Ｆ Therefore, for example, when accelerating, the pitch angle θ Ｐ When suppressing or reducing the increase in the torque, the controller 12 relatively increases the drive force distribution to the rear wheels 26 .

[0027] Here, the relationship between the configuration of the chassis system and attitude control during acceleration has been described, but the controller 12 also performs attitude control during deceleration by adjusting the distribution of driving force between the front wheels 21 and the rear wheels 26. However, during deceleration, the electric vehicle 100 assumes an attitude in which the front portion sinks (a so-called nose dive attitude), which is the opposite of the above, so the controller 12 adjusts the distribution of driving force between the front wheels 21 and the rear wheels 26 accordingly. Furthermore, hereinafter, unless otherwise specified, the attitude of the electric vehicle 100 refers to the attitude in the fore-and-aft direction, i.e., the pitch angle θ Ｐ In other words, the attitude control by adjusting the driving force distribution is performed by adjusting the pitch angle θ Ｐ Control of pitch rate Δ ＰControl of pitch angle θ Ｐ and pitch rate Δ Ｐ The pitch rate Δ Ｐ is the pitch angle θ Ｐ is the time rate of change of

[0028] 3A and 3B are explanatory diagrams showing the attitude and changes of the electric vehicle 100. Fig. 3A shows the attitude of the electric vehicle 100 when stopped, which is determined at the time of manufacture, etc. Fig. 3B shows the attitude of the electric vehicle 100 when stopped, which changes depending on the specific usage situation.

[0029] As shown in FIG. 3A, in the posture of the electric vehicle 100 when it is stopped (hereinafter referred to as the standard posture) determined at the time of manufacture, etc., a load WL is applied to the front wheel 21 due to the vehicle weight. Ｆ A load WL is applied to the rear wheel 26. Ｒ In the standard posture, for example, the height of the vehicle shed 101 from the road surface at the front end (hereinafter referred to as the front vehicle height) H Ｆ１ and the height of the vehicle shed 101 from the road surface at the rear end (hereinafter referred to as rear vehicle height) H Ｒ１ In other words, when the vehicle is stopped, the vehicle shed 101 is horizontal.

[0030] As shown in FIG. 3B, for example, when a driver 33 sits in the driver's seat at the front and two passengers 34 sit in the rear seats, the load WL of the front wheels 21 and the rear wheels 26 is Ｆ , W.L. Ｒ However, the amount of increase is Ｒ Therefore, even when the electric vehicle 100 is stopped, the center of gravity O Ｇ In FIG. 3B, for convenience, the center of gravity in the standard posture is shown as "O Ｇ " and the center of gravity after the transition is "O Ｇ The front vehicle height H Ｆ２ is the front vehicle height H in the standard position Ｆ１ The rear vehicle height H Ｒ２ is the front vehicle height H in the standard position Ｒ１That is, just as when the electric vehicle 100 assumes a nose-up posture due to acceleration, the vehicle shed 101 assumes a posture inclined rearward with respect to the standard posture (hereinafter referred to as a backward-leaning posture) even when the electric vehicle 100 is stopped.

[0031] Although not shown in the drawings, when the driver 33 is seated in the driver's seat, the passenger 34 is seated in the passenger seat, and the passenger 34 is not seated in the rear seat, the load WL of the front wheel 21 is the opposite to the above. Ｆ Therefore, even when the electric vehicle 100 is stopped, the center of gravity O Ｇ The front vehicle height H Ｆ２ is the front vehicle height H in the standard position Ｆ１ The rear vehicle height H Ｒ２ is the front vehicle height H in the standard position Ｒ１ That is, just as when the vehicle assumes a nose-dive posture due to deceleration, the vehicle shed 101 assumes a posture that is tilted forward with respect to the standard posture (hereinafter referred to as a forward tilt posture) even when the electric vehicle 100 is stopped.

[0032] As described above, the actual longitudinal posture (hereinafter referred to as the basic posture) of the electric vehicle 100 when it is stopped changes depending on the specific usage situation of the electric vehicle 100. In Fig. 3(B) , the riding position of the occupant is used as an example, but the same changes as those described above can also occur depending on the position of luggage, the load amount, etc.

[0033] In the attitude control by adjusting the driving force distribution, the center of gravity O is adjusted based on the assumption that the electric vehicle 100 maintains a standard attitude when stopped. Ｇ Around the pitch angle θ Ｐ Therefore, when the standard posture is changed to the basic posture as described above, or when the basic posture is changed to another basic posture, the center of gravity O Ｇ If the actual position of the vehicle shed 101 changes, the moment expected in the attitude control will not be generated on the vehicle shed 101. As a result, in attitude control that does not take the basic attitude into consideration, the attitude of the electric vehicle 100 may not become the expected attitude.

[0034] Therefore, in this embodiment, the controller 12 performs attitude control by adjusting the drive force distribution in consideration of the basic attitude of the electric vehicle 100 as follows.

[0035] <Configuration for Posture Control> Fig. 4 is a block diagram showing the configuration of the posture control controller 12. As shown in Fig. 4, the controller 12 includes a total driving force calculation unit 41, a basic distribution calculation unit 42, a posture control calculation unit 43, a driving force setting unit 44, a front motor control unit 45, and a rear motor control unit 46.

[0036] The total driving force calculation unit 41 calculates the total driving force TQ based on the operation of the accelerator pedal. The total driving force TQ is the driving force required for the electric vehicle 100. For example, the total driving force calculation unit 41 calculates the total driving force TQ based on the operation of the accelerator pedal A. ＰＯ and the total driving force TQ, and by referring to this map, the accelerator opening A ＰＯ The total driving force TQ corresponding to the above is calculated.

[0037] The total driving force calculation unit 41 calculates the accelerator opening A ＰＯ Instead of calculating the total driving force TQ based on the above, the total driving force TQ can be calculated based on commands from an ADAS (Advanced Drive Assistance System) or an AD (Autonomous Driving) system. These systems are systems that replace the driver's operation of the accelerator pedal, and therefore the calculation of the total driving force TQ that the total driving force calculation unit 41 performs based on commands from these systems is essentially a calculation based on the operation of the accelerator pedal.

[0038] The basic distribution calculation unit 42 distributes the total driving force TQ to the front wheels 21 and the rear wheels 26 in accordance with the basic distribution. The basic distribution is a driving force distribution determined so as to optimize the electricity consumption within a range that ensures driving stability, and is determined in advance through experiments, simulations, etc. For example, if the front motor 23 and the rear motor 28 are the same type and the electric vehicle 100 travels at a constant speed on a flat road, the basic distribution is front wheels:rear wheels = 50:50. The basic distribution may change depending on the specific driving state of the electric vehicle 100 (such as the steering state).

[0039] In this embodiment, the basic distribution calculation unit 42 calculates the first front torque target value T based on the basic distribution and the total driving force TQ. Ｆ１ ＊ , and the first rear torque target value T Ｒ１ ＊ The first front torque target value T Ｆ１ ＊ is the front wheel driving force F according to the basic distribution Ｆ represents the front motor torque generated on the front wheels 21. Ｒ１ ＊ is the rear wheel driving force F according to the basic distribution Ｒ represents the rear torque generated on the rear wheels 26. In the following, the first front torque target value T Ｆ１ ＊ and the first rear torque target value T Ｒ１ ＊ The combination of the basic driving force distribution (T Ｆ１ ＊ , T Ｒ１ ＊ )

[0040] The attitude control calculation unit 43 detects the basic attitude of the electric vehicle 100 and calculates a corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ In this embodiment, the posture control calculation unit 43 calculates the seat belt fastening / unfastening signal S ｓｅａｔ The basic attitude of the electric vehicle 100 is detected based on the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３＊ ) is the final front torque target value (hereinafter referred to as the third front torque target value T Ｆ３ ＊ ) and the rear torque target value (hereinafter, the third rear torque target value T Ｒ３ ＊ The configuration of the attitude control calculation unit 43 will be described in detail later.

[0041] The driving force setting unit 44 determines the distribution of driving force generated by the front wheels 21 and the rear wheels 26 based on the basic driving force distribution (T Ｆ１ ＊ , T Ｒ１ ＊ ) or corrective driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ For example, when the attitude control is turned on by settings or the like, or when the execution of the attitude control is permitted, the driving force setting unit 44 sets the driving force distribution of the front wheels 21 and the rear wheels 26 to the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ On the other hand, when the attitude control is turned off by settings or the like, or when the execution of attitude control is not permitted, the driving force setting unit 44 sets the driving force distribution between the front wheels 21 and the rear wheels 26 to the basic driving force distribution (T Ｆ１ ＊ , T Ｒ１ ＊ ) in the present embodiment. For simplicity, it is assumed that the posture control is turned on or the execution of the posture control is permitted by settings or the like. That is, in the following, the driving force setting unit 44 sets the driving force distribution of the front wheels 21 and the rear wheels 26 to the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) shall be set.

[0042] The front motor control unit 45 controls the front motor 23 via the front inverter 22 so that the driving force set by the driving force setting unit 44 is generated at the front wheels 21. A first front torque target value T Ｆ１＊ When this is input, the front motor control unit 45 controls the front motor 23 to generate the first front torque target value T Ｆ１ ＊ On the other hand, a front torque corresponding to a third front torque target value T Ｆ３ ＊ When this is input, the front motor control unit 45 controls the front motor 23 to generate the third front torque target value T Ｆ３ ＊ This generates a front torque corresponding to the front wheel drive force F Ｆ is controlled to the basic driving force or the corrected driving force.

[0043] The rear motor control unit 46 controls the rear motor 28 via the rear inverter 27 so that the driving force set by the driving force setting unit 44 is generated at the rear wheels 26. A first rear torque target value T Ｒ１ ＊ When this is input, the rear motor control unit 46 controls the rear motor 28 to generate the first rear torque target value T Ｒ１ ＊ On the other hand, a third rear torque target value T Ｒ３ ＊ When this is input, the rear motor control unit 46 controls the rear motor 28 to generate the third rear torque target value T Ｒ３ ＊ This generates a rear torque corresponding to the rear wheel driving force F Ｒ is controlled to the basic driving force or the corrected driving force.

[0044] The front motor control unit 45 and the rear motor control unit 46 are configured to control the basic driving force distribution (T Ｆ１ ＊ , T Ｒ１ ＊ ) or corrective driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) and configures a drive wheel control unit that controls (drives) the front wheels 21 and rear wheels 26.

[0045] 5 is a block diagram showing the configuration of the attitude control calculation unit 43. As shown in FIG. 5, the attitude control calculation unit 43 includes a first calculation unit 51 and a second calculation unit 52.

[0046] The first calculation unit 51 calculates a driving force distribution for posture control (T Ｆ２ ＊ , T Ｒ２ ＊ The first calculation unit 51 calculates the attitude control driving force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) includes a basic pitch correction unit 53.

[0047] The basic pitch correction unit 53 adjusts the driving force distribution for posture control (T Ｆ２ ＊ , T Ｒ２ ＊ That is, the basic pitch correction unit 53 is a driving force distribution calculation unit that calculates the attitude control driving force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) is calculated. Therefore, the attitude control driving force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) is a front torque target value (hereinafter referred to as the second front torque target value T Ｆ２ ＊ ) and the rear torque target value (hereinafter referred to as the second rear torque target value T Ｒ２ ＊ Specifically, the basic pitch correction unit 53 calculates the pitch angle θ based on, for example, a predetermined vehicle model of the electric vehicle 100. Ｐ is the target pitch angle (hereinafter referred to as the target pitch angle θ Ｐ ＊The basic driving force distribution (T Ｆ１ ＊ , T Ｒ１ ＊ ) is corrected to obtain the attitude control driving force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) is calculated.

[0048] That is, in this embodiment, the attitude control performed by the electric vehicle 100 is performed based on the actually generated pitch angle θ Ｐ This is done by feedforward control, which corrects (adjusts) the driving force distribution based on a vehicle model, regardless of the above.

[0049] The second calculation unit 52 detects the basic attitude of the electric vehicle 100, and calculates the attitude control driving force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) is corrected to obtain the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ The second calculation unit 52 is configured to perform this calculation by including a basic attitude detection unit 54, a correction coefficient calculation unit 55, and a center of gravity correction unit 56.

[0050] The basic posture detection unit 54 detects the basic posture of the electric vehicle 100. In this embodiment, the basic posture detection unit 54 detects the basic posture of the electric vehicle 100 by detecting a seat belt fastening / unfastening signal S ｓｅａｔ Specifically, the presence or absence of an occupant in each seat is determined by the basic posture of the electric vehicle 100 (the center of gravity O after transition) Ｇ Since this is information that determines the seat belt fastening / unfastening position, the basic posture detection unit 54 detects the seat belt fastening / unfastening signal S ｓｅａｔ Then, the basic posture detection unit 54 outputs the number of passengers in the front seats (driver's seat) and the rear seats (passenger seat) as information representing the basic posture of the electric vehicle 100.

[0051] The correction coefficient calculation unit 55 calculates the attitude control driving force distribution (T Ｆ２ ＊ , T Ｒ２ ＊In this embodiment, the correction coefficient K is used to correct the ratio of the driving force distribution between the front wheels 21 and the rear wheels 26. The correction coefficient calculation unit 55 calculates the correction coefficient K according to the number of passengers in the front seats and the rear seats, based on Table 1 below. "α" in Table 1 is a predetermined value determined in advance through experimentation, simulation, or the like.

[0052]

[0053] The center of gravity correction unit 56 corrects the center of gravity O Ｇ The amount of the forward or backward shift of the attitude control driving force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) is corrected by correcting the ratio of the driving force distribution between the front wheels 21 and the rear wheels 26. Ｆ３ ＊ , T Ｒ３ ＊ ) is calculated.

[0054] In this embodiment, the center of gravity correction unit 56 first calculates the attitude control drive force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) the distribution ratio of the driving force to the rear wheels 26 (hereinafter referred to as the distribution ratio) D Ｒ Calculate the percentage.

[0055]

[0056] Thereafter, the gravity center correction unit 56 calculates the distribution ratio D of the rear wheels 26 using the correction coefficient K according to the following formula (2): Ｒ is corrected, and the corrected driving force distribution ratio to the rear wheels 26 (hereinafter referred to as the corrected distribution ratio) D Ｒ The corrected allocation ratio D' (%) is calculated. Ｒ ' is the distribution ratio of the driving force corrected according to the basic attitude while controlling the attitude in the longitudinal direction.

[0057]

[0058] Then, the center of gravity correction unit 56 calculates the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ That is, the center of gravity correction unit 56 calculates the corrected allocation ratio D Ｒ According to the above, the attitude control driving force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) is redistributed to the front wheels 21 and rear wheels 26.

[0059]

[0060] As can be seen from the setting of the correction coefficient K, the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) is the posture control driving force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) is a distribution in which the distribution of the driving force to the front wheels 21 is increased. Ｆ３ ＊ , T Ｒ３ ＊ ) is the attitude control drive force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) the distribution of driving force to the rear wheels 26 is increased.

[0061] <Operation> Hereinafter, the operation of the attitude control of the electric vehicle 100 configured as described above will be described.

[0062] 6 is a flowchart showing the operation of the attitude control of the electric vehicle 100. As shown in FIG. 6, in step S10, the basic distribution calculation unit 42 calculates the basic driving force distribution (T Ｆ１ ＊ , T Ｒ１ ＊ Next, in step S11, the basic pitch correction unit 53 calculates the basic driving force distribution (TＦ１ ＊ , T Ｒ１ ＊ ) to obtain the posture control driving force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) is calculated.

[0063] On the other hand, in step S12, the basic posture detection unit 54 detects the seat belt fastening / unfastening signal S ｓｅａｔ In step S13, the basic posture detection unit 54 acquires the acquired seat belt fastening / unfastening signal S ｓｅａｔ Then, in step S14, the correction coefficient calculation unit 55 calculates a correction coefficient K based on the basic attitude of the electric vehicle 100, i.e., the number of passengers in the front seats and the rear seats. After that, in step S15, the center of gravity correction unit 56 calculates a driving force distribution for attitude control (T Ｆ２ ＊ , T Ｒ２ ＊ ) is corrected to obtain a corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ Then, in step S16, the front motor control unit 45 and the rear motor control unit 46 calculate the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) to drive the front wheels 21 and the rear wheels 26 by operating the front motor 23 and the rear motor 28 in accordance with the above.

[0064] Corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) is the center of gravity O according to the basic posture Ｇ Therefore, the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３＊ ) by driving the front wheels 21 and the rear wheels 26 in accordance with the above formula, the electric vehicle 100 assumes the basic posture and the center of gravity O Ｇ Around the pitch angle θ Ｐ As a result, according to the attitude control of the electric vehicle 100 described above, the attitude of the electric vehicle 100 converges to a target attitude during acceleration or deceleration, regardless of the number of occupants, the specific riding position, etc. The target attitude during acceleration or deceleration is, for example, a standard attitude (θ Ｐ ≒0) or the base posture, which is the actual initial posture.

[0065] Second Embodiment In the first embodiment, the basic posture detection unit 54 detects the seat belt fastening / unfastening signal S ｓｅａｔ The basic posture of the electric vehicle 100 is detected by identifying the number of passengers in the front and rear seats based on the vehicle height H Ｆ２ and rear vehicle height H Ｒ２ , or the difference between them ΔH ＦＲ (=H Ｆ２ -H Ｒ２ ) can be used to detect the basic posture of the electric vehicle 100. Ｆ２ and rear vehicle height H Ｒ２ The difference ΔH ＦＲ An example will be described in which the basic attitude of the electric vehicle 100 is detected by identifying the position of the electric vehicle 100 .

[0066] 7 is a block diagram showing the configuration of the attitude control calculation unit 43 in the second embodiment. As shown in Fig. 7, the attitude control calculation unit 43 in the second embodiment differs from the first embodiment in the configuration of the second calculation unit 52. Specifically, the attitude control calculation unit 43 in the second embodiment includes a vehicle stop detection unit 201, a basic attitude detection unit 202 and a correction coefficient calculation unit 203 that are different from those in the first embodiment, and a center of gravity correction unit 56 that is the same as that in the first embodiment.

[0067] The vehicle stop detection unit 201 detects the vehicle speed VSP and the road surface gradient φ ＬＳThe vehicle stop detection unit 201 detects whether the electric vehicle 100 is stopped on a flat road based on the vehicle speed VSP being zero within a predetermined error range (VSP≈0) and the road surface gradient φ ＬＳ is zero within a predetermined error range, (φ ＬＳ ≈0), it is determined that the electric vehicle 100 is stopped on a flat road.

[0068] When the basic posture detection unit 202 detects that the vehicle is stopped on a flat road, it outputs a suspension stroke signal S ｓｕｓ Then, the basic posture detection unit 202 obtains the obtained suspension stroke signal S ｓｕｓ Based on this, the front vehicle height H Ｆ２ and rear vehicle height H Ｒ２ , or the difference between them ΔH ＦＲ By calculating the above, the posture of the electric vehicle 100 when it is stopped is detected. Here, it is assumed that the electric vehicle 100 is in a basic posture that is different from the standard posture. Ｆ２ and rear vehicle height H Ｒ２ , or the difference between them ΔH ＦＲ is calculated based on the structural model of the vehicle body. ｓｕｓ In this embodiment, the basic attitude detection unit 202 detects the front vehicle height H Ｆ２ and rear vehicle height H Ｒ２ The difference ΔH ＦＲ Calculate the following.

[0069] The correction coefficient calculation unit 203 calculates the attitude control driving force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) is calculated. This is the same as the correction coefficient calculation unit 203 in the first embodiment. However, the correction coefficient calculation unit 203 in the second embodiment calculates a correction coefficient K used to correct the front vehicle height H Ｆ２ and rear vehicle height H Ｒ２ The difference ΔH ＦＲ The correction coefficient K is calculated based on the front vehicle height H Ｆ２ and rear vehicle height H Ｒ２ The difference ΔH ＦＲ The relationship between the correction coefficient K and the saturation coefficient K is determined in advance by experiment, simulation, or the like.

[0070] FIG. 8 shows the front vehicle height H Ｆ２ and rear vehicle height H Ｒ２ The difference ΔH ＦＲ 8 is a graph illustrating the relationship between the front vehicle height H and the correction coefficient K. As shown in FIG. Ｆ２ and rear vehicle height H Ｒ２ The difference ΔH ＦＲ The correction coefficient K is predetermined to increase or decrease in proportion to the difference ΔH ＦＲ is ΔH ＦＲ If K', the corresponding correction coefficient K is K'. The nature of the correction coefficient K calculated by the correction coefficient calculation unit 203 is the same as in the first embodiment.

[0071] In this way, the front vehicle height H Ｆ２ and rear vehicle height H Ｒ２ The difference ΔH ＦＲ and the correction coefficient K, the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) is the posture control driving force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) is a distribution in which the distribution of the driving force to the front wheels 21 is increased. Ｆ３ ＊ , T Ｒ３ ＊ ) is the attitude control drive force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) the distribution of driving force to the rear wheels 26 is increased.

[0072] 9 is a flowchart showing the operation of the posture control of the second embodiment. As shown in FIG. 9, in step S20, the basic distribution calculation unit 42 calculates the basic driving force distribution (T Ｆ１ ＊ , T Ｒ１ ＊Next, in step S21, the basic pitch correction unit 53 calculates the basic driving force distribution (T Ｆ１ ＊ , T Ｒ１ ＊ ) to obtain the posture control driving force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) is calculated.

[0073] On the other hand, in step S22, the vehicle stop detection unit 201 calculates the vehicle speed VSP and the road surface gradient φ ＬＳ Then, in step S23, the vehicle stop detection unit 201 detects whether or not the electric vehicle 100 is stopped based on the vehicle speed VSP. When the vehicle speed VSP is substantially zero and it is determined that the electric vehicle 100 is stopped, the process proceeds to step S24. In step S24, the vehicle stop detection unit 201 obtains the road surface gradient φ ＬＳ If it is determined that the road surface on which the electric vehicle 100 is stopped is flat, the process proceeds to step S25, and the basic attitude detection unit 202 detects the suspension stroke signal S ｓｕｓ Get.

[0074] In step S25, the basic posture detection unit 202 detects the suspension stroke signal S ｓｕｓ Specifically, the basic posture detection unit 202 detects the basic posture of the electric vehicle 100 based on the suspension stroke signal S ｓｕｓ Based on this, the front vehicle height H Ｆ２ and rear vehicle height H Ｒ２ The difference ΔH ＦＲ The basic attitude of the electric vehicle 100 is detected by calculating the above equation.

[0075] Then, in step S27, the correction coefficient calculation unit 203 calculates the front vehicle height H Ｆ２ and rear vehicle height H Ｒ２ The difference ΔH ＦＲIf it is determined in step S23 that the electric vehicle 100 is not stopped, or if it is determined in step S24 that the road surface on which the electric vehicle 100 is stopped is not flat, the process proceeds to step S30, and the previous correction coefficient K is maintained.

[0076] Then, in step S28, the center of gravity correction unit 56 calculates the attitude control drive force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) is corrected to obtain a corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ Then, in step S29, the front motor control unit 45 and the rear motor control unit 46 calculate the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) to drive the front wheels 21 and the rear wheels 26 by operating the front motor 23 and the rear motor 28 in accordance with the above.

[0077] As mentioned above, the front vehicle height H Ｆ２ and rear vehicle height H Ｒ２ , or the difference between them ΔH ＦＲ Similarly to the first embodiment, when detecting the basic attitude of the electric vehicle 100 by specifying the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) is the center of gravity O according to the basic posture Ｇ Therefore, the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) by driving the front wheels 21 and the rear wheels 26 in accordance with the basic posture, the center of gravity O Ｇ Around the pitch angle θ ＰAs a result, according to the attitude control of the second embodiment, the attitude of the electric vehicle 100 converges to a target attitude during acceleration or deceleration, similar to the first embodiment.

[0078] As described above, the front vehicle height H Ｆ２ and rear vehicle height H Ｒ２ , or the difference between them ΔH ＦＲ When detecting the basic attitude of the electric vehicle 100 by identifying the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) is the center of gravity O according to the basic posture Ｇ Therefore, in the second embodiment, the attitude of the electric vehicle 100 can be easily converged to a target attitude during acceleration or deceleration.

[0079] In the second embodiment, the suspension stroke signal S ｓｕｓ However, the basic attitude of the electric vehicle 100 may be detected using other parameters. For example, the electric vehicle 100 has a pitch angle θ Ｐ Since the pitch angle θ Ｐ Alternatively, the basic attitude of the electric vehicle 100 may be detected directly by the suspension stroke signal S ｓｕｓ Instead of the pitch angle θ Ｐ When using pitch angle θ Ｐ As in the second embodiment, the vehicle speed should be acquired when the electric vehicle 100 is stopped on a flat road.

[0080] As described above, the control method for an electric vehicle according to the first and second embodiments is a control method for an electric vehicle 100 that performs attitude control to control the attitude in the longitudinal direction by adjusting the distribution of driving force between the front wheels 21 and the rear wheels 26, which are the driving wheels. In this control method for an electric vehicle, a basic attitude, which is the actual attitude in the longitudinal direction when the electric vehicle 100 is stopped, is detected. In addition, when the electric vehicle 100 accelerates or decelerates, an attitude control driving force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) is calculated based on the basic attitude. Ｆ２ ＊ , T Ｒ２ ＊ ) is corrected to obtain the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) is calculated, and the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ The driving wheels (21, 26) are controlled according to the

[0081] In this way, the posture control driving force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) is corrected to obtain the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) is calculated, the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) is the center of gravity O according to the basic posture Ｇ Therefore, as described above, the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) by driving the front wheels 21 and the rear wheels 26 in accordance with the above formula, the electric vehicle 100 assumes the basic posture and the center of gravity O ＧAround the pitch angle θ Ｐ As a result, the attitude of the electric vehicle 100 converges to the target attitude when accelerating or decelerating.

[0082] In the control method for the electric vehicle according to the first and second embodiments, when the basic attitude is tilted forward with respect to a predetermined standard attitude, the attitude control driving force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) in which the distribution of the driving force to the front wheels 21 is increased relative to the Ｆ３ ＊ , T Ｒ３ ＊ ) is calculated. When the basic posture is tilted backward with respect to the standard posture, the posture control driving force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) in which the distribution of the driving force to the rear wheels 26 is increased relative to the Ｆ３ ＊ , T Ｒ３ ＊ ) is calculated.

[0083] The corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) is the center of gravity O after the electric vehicle 100 has assumed the basic posture. Ｇ Around the pitch angle θ Ｐ Therefore, when accelerating or decelerating, the attitude of the electric vehicle 100 is likely to converge to a target attitude.

[0084] In the control method for the electric vehicle according to the first and second embodiments, the correction coefficient K is calculated based on the basic attitude. Ｆ２ ＊ , T Ｒ２ ＊ ) the distribution ratio of the driving force of the front wheels 21 and the rear wheels 26 (D Ｒ ) is calculated. Ｒ) and the correction coefficient K, the posture in the forward / backward direction is controlled, and the corrected distribution ratio (D Ｒ Then, the corrected distribution ratio (D Ｒ According to the attitude control driving force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) to the front wheels 21 and the rear wheels 26, thereby correcting the driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) is calculated.

[0085] This corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) when the basic posture is tilted forward, the posture control driving force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ), and when the vehicle is tilted backward, the distribution of driving force to the front wheels 21 is increased. Ｆ２ ＊ , T Ｒ２ ＊ ) can increase the distribution of driving force to the rear wheels 26. Ｆ３ ＊ , T Ｒ３ ＊ ) is the center of gravity O after the electric vehicle 100 has assumed the basic posture. Ｇ Around the pitch angle θ Ｐ As a result, the attitude of the electric vehicle 100 tends to converge to a target attitude during acceleration or deceleration.

[0086] In the control methods for electric vehicles according to the first and second embodiments, the attitude control is performed by feedforward control that corrects the drive force distribution based on a vehicle model.

[0087] The basic attitude of the electric vehicle 100 is constant to the extent that it does not change at least during the trip, and the corrected driving force distribution (T Ｆ３ ＊ , TＲ３ ＊ ) is a calculation that essentially corrects the deviation from the vehicle model. Therefore, when posture control is performed by feedforward control based on the vehicle model, the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) is particularly likely to result in accurate distribution of driving force for attitude control.

[0088] In the control method for the electric vehicle according to the second embodiment, the front vehicle height H when the electric vehicle 100 is stopped on a flat road is Ｆ２ and rear vehicle height H Ｒ２ The basic posture is detected based on the

[0089] In this way, when the electric vehicle 100 is stopped on a flat road, the front vehicle height H Ｆ２ and rear vehicle height H Ｒ２ If the basic attitude is detected based on the above, accurate corrective driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) is easily calculated.

[0090] In particular, in the control method for the electric vehicle according to the second embodiment, the suspension stroke (S ｓｕｓ ) is acquired, and the stroke (S ｓｕｓ ) based on the front vehicle height H Ｆ２ , rear vehicle height H Ｒ２ , or front vehicle height H Ｆ２ and rear vehicle height H Ｒ２ The difference ΔH ＦＲ , the basic posture is detected.

[0091] In this way, by using the stroke of the suspension (31, 32), the front vehicle height H Ｆ２ , rear vehicle height H Ｒ２ , or front vehicle height H Ｆ２ and rear vehicle height H Ｒ２ The difference ΔH ＦＲ , is accurately identified.

[0092] Furthermore, in the control method for the electric vehicle according to the second embodiment, when the electric vehicle 100 is stopped on a flat road, the pitch angle θ Ｐ and obtain the pitch angle θ Ｐ The basic posture can be detected based on the above.

[0093] In this way, the pitch angle θ when the vehicle is stopped on a flat road Ｐ This also allows the basic attitude of the electric vehicle 100 to be detected accurately.

[0094] In the control method for an electric vehicle according to the first embodiment, the fastening and detachment state of the seat belt is detected, and the basic posture is detected based on the fastening and detachment state of the seat belt. In this way, when the basic posture of the electric vehicle 100 is detected based on the fastening and detachment state of the seat belt, the basic posture of the electric vehicle 100 is likely to be detected particularly accurately when the posture changes depending on the number of occupants and their riding positions. In addition, when the vehicle speed VSP and the road surface gradient φ are detected based on the fastening and detachment state of the seat belt, the basic posture of the electric vehicle 100 is likely to be detected particularly accurately. ＬＳ Regardless of this, there is also the advantage that the basic attitude of the electric vehicle 100 can be detected accurately.

[0095] The control device for an electric vehicle according to the first and second embodiments is a control device (controller 12) for an electric vehicle 100 that performs attitude control to control the attitude in the longitudinal direction by adjusting the distribution of driving force between the front wheels 21 and the rear wheels 26, which are the driving wheels. This control device (controller 12) includes a basic attitude detection unit (54, 202) that detects a basic attitude, which is the attitude in the longitudinal direction when the electric vehicle 100 is stopped, and an attitude control driving force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) and a driving force distribution calculation unit (53) for calculating a driving force distribution for posture control (T Ｆ２ ＊ , T Ｒ２ ＊ ) is corrected to obtain the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) and a correction unit (56) for calculating the corrected driving force distribution (T Ｆ３＊ , T Ｒ３ ＊ and a driving wheel control unit (45, 46) for controlling the driving wheels (21, 26) in accordance with the driving wheel control signal.

[0096] In this way, the posture control driving force distribution (T Ｆ２ ＊ , T Ｒ２ ＊ ) is corrected to obtain the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) is calculated, the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) is the center of gravity O according to the basic posture Ｇ Therefore, the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) by driving the front wheels 21 and the rear wheels 26, the electric vehicle 100 assumes the basic posture and the center of gravity O Ｇ Around the pitch angle θ Ｐ As a result, the attitude of the electric vehicle 100 converges to the target attitude when accelerating or decelerating.

[0097] The control programs for the electric vehicle according to the first and second embodiments are control programs for the electric vehicle 100 that perform attitude control to control the attitude in the longitudinal direction by adjusting the distribution of driving force between the front wheels 21 and the rear wheels 26, which are the driving wheels. The control program for the electric vehicle includes a control device (controller 12) for the electric vehicle 100, which includes a basic attitude detection unit (54, 202) that detects the basic attitude, which is the attitude in the longitudinal direction when the electric vehicle 100 is stopped; Ｆ２ ＊ , T Ｒ２ ＊ a driving force distribution calculation unit (53) for calculating a driving force distribution for posture control (T Ｆ２＊ , T Ｒ２ ＊ ) is corrected to obtain the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ ) correction unit (56) that calculates the corrected driving force distribution (T Ｆ３ ＊ , T Ｒ３ ＊ and a drive wheel control unit (45, 46) for controlling the drive wheels (21, 26) in accordance with the control program. This control program can be provided by being stored in an arbitrary storage medium.

[0098] The above describes embodiments of the present invention, but the configurations described in the above embodiments and each modified example only show some of the application examples of the present invention and are not intended to limit the technical scope of the present invention.

Claims

1. A control method for an electric vehicle that performs attitude control to control the attitude in the longitudinal direction by adjusting the drive force distribution between the front and rear drive wheels, comprising: detecting a basic attitude which is the actual attitude in the longitudinal direction when the electric vehicle is stopped; when the electric vehicle accelerates or decelerates, calculating a drive force distribution for attitude control which is the drive force distribution for controlling the attitude in the longitudinal direction; calculating a corrected drive force distribution by correcting the drive force distribution for attitude control based on the basic attitude; controlling the drive wheels according to the corrected drive force distribution; when the basic attitude is inclined forward with respect to a predetermined standard attitude, calculating the corrected drive force distribution in which the distribution of the drive force to the front wheels is increased with respect to the drive force distribution for attitude control; when the basic attitude is inclined rearward with respect to the standard attitude, calculating the corrected drive force distribution in which the distribution of the drive force to the rear wheels is increased with respect to the drive force distribution for attitude control. A control method for an electric vehicle.

2. The control method for an electric vehicle according to claim 1, comprising: calculating a correction coefficient based on the basic attitude; calculating the distribution ratio of the drive forces of the front and rear wheels in the drive force distribution for attitude control; using the distribution ratio and the correction coefficient to calculate a corrected distribution ratio which is the distribution ratio corrected according to the basic attitude while controlling the attitude in the longitudinal direction; calculating the corrected drive force distribution by redistributing the drive force distribution for attitude control to the front and rear wheels according to the corrected distribution ratio. A control method for an electric vehicle.

3. The control method for an electric vehicle according to claim 1, comprising: performing the attitude control by feedforward control that corrects the drive force distribution based on a vehicle model. A control method for an electric vehicle.

4. The control method for an electric vehicle according to claim 1, comprising: detecting the basic attitude based on the front vehicle height and the rear vehicle height when the electric vehicle is stopped on a flat road. A control method for an electric vehicle.

5. The control method for an electric vehicle according to claim 4, comprising: acquiring the stroke of the suspension when the electric vehicle is stopped on a flat road; detecting the basic attitude by specifying the front vehicle height, the rear vehicle height, or the difference between the front vehicle height and the rear vehicle height based on the stroke of the suspension. A control method for an electric vehicle.

6. The control method for an electric vehicle according to claim 4, comprising: When the electric vehicle is parked on a flat road, obtain the pitch angle of the electric vehicle, Based on the pitch angle, detect the basic posture, A control method for an electric vehicle.

7. A control method for an electric vehicle according to claim 1, Detect the attachment / detachment state of the seat belt, Based on the attachment / detachment state of the seat belt, detect the basic posture, A control method for an electric vehicle.

8. A control device for an electric vehicle that performs attitude control to control the attitude in the front-rear direction by adjusting the drive force distribution between the front wheels and the rear wheels, which are drive wheels, A basic posture detection unit that detects the basic posture, which is the actual posture in the front-rear direction when the electric vehicle is parked, A drive force distribution calculation unit that calculates a drive force distribution for attitude control, which is the drive force distribution for controlling the attitude in the front-rear direction when the electric vehicle accelerates or decelerates, A correction unit that calculates a corrected drive force distribution by correcting the drive force distribution for attitude control based on the basic posture, A drive wheel control unit that controls the drive wheels according to the corrected drive force distribution, Comprising, When the basic posture is tilted forward with respect to a predetermined standard posture, calculate the corrected drive force distribution in which the distribution of the drive force to the front wheels is increased with respect to the drive force distribution for attitude control, When the basic posture is tilted backward with respect to the standard posture, calculate the corrected drive force distribution in which the distribution of the drive force to the rear wheels is increased with respect to the drive force distribution for attitude control, A control device for an electric vehicle.