Control method for electric vehicles, and control device for electric vehicles

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

[Technical Field]

[0001] The present invention relates to a control method for electric vehicles and a control device for electric vehicles. [Background technology]

[0002] JP4876534B2 discloses a technology for reducing the pitch rate of an in-wheel motor type vehicle when the vehicle passes over bumps or uneven surfaces in the road, in which the suspension effect cannot be fully obtained. More specifically, it discloses applying different braking and driving forces to the front and rear wheels, and then, if a change in pitch rate is detected, applying different braking and driving forces to the left and right wheels at a predetermined interval. [Overview of the Initiative]

[0003] Conventionally, electric vehicles are known to control their attitude by adjusting the distribution of driving force to multiple drive wheels. However, with conventional attitude control methods, it is sometimes not possible to correctly control the attitude of an electric vehicle to a target attitude.

[0004] For example, changes in the specific usage conditions of an electric vehicle, such as the number of occupants, their specific seating positions, or the amount of cargo loaded in the cargo area, can cause the reference point (center of gravity) for attitude changes during acceleration or deceleration. Conventional attitude control controls the attitude of an electric vehicle based on its state at the time of manufacture, for example. Therefore, when there are changes in the specific usage conditions of an electric vehicle, as described above, errors can occur, and the attitude of the electric vehicle may not converge precisely to the target attitude.

[0005] Therefore, the present invention aims to provide a control method for electric vehicles and a control device for electric vehicles that can bring the attitude of an electric vehicle to a target attitude during acceleration or deceleration, regardless of the specific usage conditions 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 vehicle's attitude in the longitudinal direction by adjusting the distribution of driving force between the front and rear wheels, which are the drive wheels. In this electric vehicle control method, the basic attitude, which is the actual longitudinal attitude of the electric vehicle when it is stationary, is detected. When the electric vehicle accelerates or decelerates, an attitude control driving force distribution, which is the distribution of driving force that controls the attitude in the longitudinal direction, is calculated. Then, by correcting the attitude control driving force distribution based on the basic attitude, a corrected driving force distribution is calculated, and the drive wheels are controlled by this corrected driving force distribution. [Brief explanation of the drawing]

[0007] [Figure 1] Figure 1 is an explanatory diagram showing the schematic configuration of an electric vehicle. [Figure 2] Figure 2 is an explanatory diagram showing the schematic structure of the chassis system. [Figure 3] Figure 3 is an explanatory diagram showing the attitude of an electric vehicle and how it changes. [Figure 4] Figure 4 is a block diagram showing the configuration of the controller for attitude control. [Figure 5] Figure 5 is a block diagram showing the configuration of the attitude control calculation unit. [Figure 6] Figure 6 is a flowchart showing the actions involved in the attitude control of an electric vehicle. [Figure 7] Figure 7 is a block diagram showing the configuration of the attitude control calculation unit in the second embodiment. [Figure 8] Figure 8 is a graph illustrating the relationship between the difference between the front and rear vehicle heights and the correction coefficient. [Figure 9] Figure 9 is a flowchart showing the operation related to attitude control in the second embodiment. [Modes for carrying out the invention]

[0008] Embodiments of the present invention will be described below with reference to the drawings.

[0009] [First Embodiment] <Configuration of electric vehicles> Figure 1 is an explanatory diagram showing the schematic configuration of the electric vehicle 100. The electric vehicle 100 is, for example, an electric vehicle or a hybrid vehicle, which is a vehicle that can drive or brake one or more drive wheels with an electric motor. In particular, in this embodiment, the electric vehicle 100 is a so-called 4WD (four-wheel drive) vehicle, and the driving force generated in each of the multiple drive wheels can be controlled (adjusted). Specifically, as shown in Figure 1, the electric vehicle 100 comprises 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 the front wheels 21, which are the first drive wheels. The front-wheel drive system 10 includes a front inverter 22 and a front motor 23.

[0011] The front inverter 22 drives the front motor 23 by converting the DC power output by a battery (not shown) into AC power and supplying it to the front motor 23. Also, when the front motor 23 is rotated by the front wheels 21, the front inverter 22 charges the battery by converting the regenerative AC power generated by the front motor 23 into DC power and inputting it to 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 the front drive shaft 24, and the driving force (hereinafter referred to as front wheel driving force F) is transmitted to the front wheels 21. F This causes the following to occur.

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

[0014] The rear inverter 27 drives the rear motor 28 by converting the DC power output by the battery into AC power and supplying it to the rear motor 28. Also, when the rear motor 28 is rotated by the rear wheels 26, the rear inverter 27 charges the battery by converting the regenerative AC power generated by the rear motor 28 into DC power and inputting it to the battery.

[0015] The rear motor 28 is an electric motor that drives the rear wheels 26. The rear motor 28 is, for example, 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 the rear drive shaft 29, providing the rear wheels 26 with driving force (hereinafter referred to as rear wheel driving force F). R This causes the following to occur.

[0016] The controller 12 consists of 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 in 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 drive wheels.

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

[0018] When controlling the operation of the electric vehicle 100, the controller 12 can appropriately acquire various parameters representing the operation state of the electric vehicle 100, etc., by a sensor (not shown) or by calculation. For example, the electric vehicle 100 has an accelerator opening degree sensor (not shown) that detects the accelerator opening degree A PO . Therefore, the controller 12 can appropriately acquire the accelerator opening degree A PO . The accelerator opening degree A PO is a parameter representing the operation amount of the accelerator pedal. Also, the controller 12 appropriately acquires the vehicle speed VSP of the electric vehicle 100 by a sensor (not shown) or by calculation.

[0019] In addition, in this embodiment, the electric vehicle 100 includes a sensor (not shown) (for example, a buckle sensor for each seat belt) that detects the attachment / detachment state of the seat belts provided on the driver's seat, the front passenger seat, and the rear seat. Therefore, the controller 12 can appropriately acquire a signal indicating the attachment / detachment state of the seat belt for each seat (hereinafter referred to as the seat belt attachment / detachment signal S seat ). Also, the electric vehicle 100 includes a sensor (so-called suspension stroke sensor) that detects the stroke amount, etc., of the front suspension 31 (see FIG. 2) provided on the front wheels 21 and the rear suspension 32 (see FIG. 2) provided on the rear wheels 26. Therefore, the controller 12 can appropriately acquire a signal indicating the stroke amount, etc., of each suspension (hereinafter referred to as the suspension stroke signal S sus ).

[0020] Furthermore, in this embodiment, the electric vehicle 100 includes a pitch sensor that detects the pitch angle θ P or pitch rate of the electric vehicle 100. Therefore, the controller 12 can appropriately acquire the pitch angle θ P and pitch rate of the electric vehicle 100. Also, the controller 12 obtains from a navigation system (not shown) the current location of the electric vehicle 100 and the gradient of the road surface on which the electric vehicle 100 travels, etc. (hereinafter referred to as the road surface gradient φ LSThe road surface gradient φ can be obtained as appropriate. LS This can be obtained by calculation based on the vehicle speed VSP, acceleration G, or changes therein of the electric vehicle 100.

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

[0022] For example, front-wheel drive force F F Rear-wheel drive force F R If the electric vehicle 100 is accelerated by either of these, the load shifts to the rear (negative side in the X direction) of the electric vehicle 100. As a result, the center of gravity O G Centered at, pitch angle θ P A moment is generated that acts in a direction that increases the force. Therefore, when the electric vehicle 100 accelerates, in principle, the electric vehicle 100 will assume a posture in which the front part, which is the part on the positive X direction, is lifted up (a so-called nose-up posture).

[0023] On the other hand, front-wheel drive force F F The torque of the front motor 23 that generates the front torque (hereinafter referred to as front torque) acts on the vehicle body 101 via the front suspension 31. Specifically, the front torque is generated around the virtual center of rotation O F Around the pitch angle θ P This generates a moment that acts in a direction that reduces the force. That is, when the electric vehicle 100 accelerates, the front torque suppresses nose-up. Similarly, the rear-wheel drive force F R The torque generated by the rear motor 28 (hereinafter referred to as rear torque) acts on the vehicle body 101 via the rear suspension 32, creating a virtual rotation center O R Around the pitch angle θ PThis generates a moment that acts in a direction that reduces the force. Therefore, when the electric vehicle 100 accelerates, the rear torque suppresses nose-up.

[0024] Furthermore, the magnitude of the effect of front torque on suppressing nose-up during acceleration is determined by the anti-scat angle θ. F It depends on the magnitude of the anti-scat angle θ. Similarly, the magnitude of the effect of rear torque on suppressing nose-up during acceleration is related to the anti-scat angle θ. R It depends on the magnitude of the anti-scut angle. Therefore, by adjusting the drive force distribution of the front wheels 21 and rear wheels 26 so that a larger distribution is given to the drive wheels with a relatively large anti-scut angle, the effect of suppressing nose-up while maintaining the total drive force is increased. Accordingly, in this embodiment, the controller 12 adjusts the drive force distribution of the front wheels 21 and rear wheels 26 to control the longitudinal attitude of the electric vehicle 100 (i.e., the pitch angle θ). P Performs attitude control to regulate (or its fluctuations).

[0025] Note that the virtual rotation center O F This is the instantaneous and virtual center of rotation generated in the vehicle body (especially the vehicle upper 101) by the transmission of front torque, and is predetermined by the specific configuration of the front suspension 31, etc. Similarly, the virtual center of rotation O of the rear part R This is the instantaneous and virtual center of rotation generated in the vehicle body (especially the vehicle upper 101) by the transmission of rear torque, and is predetermined by the specific configuration of the rear suspension 32, etc. Also, the anti-scat angle θ F In the XZ plane, the rotation center of the front wheel 21 and the virtual rotation center O F It is the angle formed by the line connecting the two points and the line parallel to the road surface. Similarly, the anti-scut angle θ R In the XZ plane, the rotation center of the rear wheel 26 and the virtual rotation center O R It is the angle formed by the line connecting the two points and the line parallel to the road surface.

[0026] In this embodiment, as shown in Figure 2, the anti-scut angle θ of the rear suspension 32 R The anti-scat angle θ of the front suspension 31 is FIt is larger than that. For this reason, for example, when accelerating, the pitch angle θ P When suppressing or reducing the increase of the force, the controller 12 relatively increases the distribution of driving force to the rear wheels 26.

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

[0028] Figure 3 is an explanatory diagram showing the posture of the electric vehicle 100 and its changes. Figure 3(A) shows the posture of the electric vehicle 100 when stationary, as determined during manufacturing, etc. Figure 3(B) shows the posture of the electric vehicle 100 when stationary, as it changes according to specific usage conditions.

[0029] As shown in Figure 3(A), in the stationary position of the electric vehicle 100 determined during manufacturing, etc. (hereinafter referred to as the standard position), the front wheels 21 are subjected to load WL due to the vehicle weight. F The load WL is applied to the rear wheel 26. R In addition, in the standard position, for example, the height of the vehicle roof 101 at the front end from the road surface (hereinafter referred to as the front vehicle height) H F1 and the height of the vehicle roof 101 from the road surface at the rear end (hereinafter referred to as rear vehicle height) H R1They are approximately equal. That is, when the vehicle is stationary, the vehicle roof 101 is horizontal.

[0030] As shown in Figure 3(B), for example, when a driver 33 is seated in the driver's seat at the front and two passengers 34 are seated in the rear seats, the load WL of the front wheels 21 and rear wheels 26 F WL R Although both increase, the amount of increase is the load WL of the rear wheel 26. R The latter is larger. Therefore, even when the electric vehicle 100 is stationary, the center of gravity is O G It transitions to the rear of the electric vehicle 100. In Figure 3(B), for convenience, the center of gravity in the standard posture is shown as "O G It is represented as " and the centroid after the transition is "O G It is represented by ′」. And the front vehicle height H F2 The front vehicle height H in the standard position. F1 It is larger than the rear vehicle height H R2 The front vehicle height H in the standard position. R1 It becomes smaller than that. In other words, as when the nose is raised due to acceleration, the vehicle roof 101 is tilted backward relative to the standard posture (hereinafter referred to as the rearward tilt posture) even when the electric vehicle 100 is stationary.

[0031] Although not shown in the diagram, when a driver 33 is in the driver's seat, a passenger 34 is in the front passenger seat, and no passenger 34 is in the rear seat, the load WL of the front wheel 21 is the opposite of the above. F Therefore, even when the electric vehicle 100 is stationary, the center of gravity O G It transitions to the front of the electric vehicle 100. Then, the front vehicle height H F2 The front vehicle height H in the standard position. F1 It becomes smaller than the rear ride height H R2 The front vehicle height H in the standard position. R1 It becomes larger than that. In other words, as when the vehicle decelerates and enters a nose-dive position, the vehicle roof 101 is tilted forward relative to the standard position (hereinafter referred to as the forward-tilted position) even when the electric vehicle 100 is stopped.

[0032] As described above, the actual longitudinal orientation (hereinafter referred to as the basic orientation) of the electric vehicle 100 when it is stationary changes depending on the specific usage conditions of the electric vehicle 100. Figure 3(B) shows the passenger's seating position as an example, but similar changes can occur depending on the position of luggage, the amount of cargo, etc.

[0033] Furthermore, in attitude control by adjusting the driving force distribution, assuming that the electric vehicle 100 maintains a standard attitude when stationary, the center of gravity O G Around the pitch angle θ P The driving force distribution is adjusted to generate a moment to control the center of gravity O. G If the actual position of changes, the moment intended for attitude control will no longer be generated on the vehicle roof 101. As a result, in attitude control that does not take the basic attitude into account, the attitude of the electric vehicle 100 may not be the intended attitude.

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

[0035] <Configuration for attitude control> Figure 4 is a block diagram showing the configuration of the controller 12 for attitude control. As shown in Figure 4, the controller 12 includes a total drive force calculation unit 41, a basic distribution calculation unit 42, an attitude control calculation unit 43, a drive 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 required driving force for the electric vehicle 100. For example, the total driving force calculation unit 41 calculates the accelerator opening A PO It has a map that associates the total driving force TQ with the accelerator opening A, and by referring to this map, the accelerator opening A POThe total driving force TQ corresponding to this is calculated.

[0037] Furthermore, the total driving force calculation unit 41 calculates the accelerator opening A as described above. PO Instead of calculating the total driving force TQ based on the driver's actions, the total driving force TQ can be calculated based on commands from an ADAS (Advanced Drive Assistance System) or AD (Autonomous Driving) system, etc. Since these systems are systems that substitute for the driver's operation of the accelerator pedal, the calculation of the total driving force TQ performed by the total driving force calculation unit 41 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 rear wheels 26 according to the basic distribution. The basic distribution is a driving force distribution determined to achieve the best possible energy efficiency while ensuring driving stability, and is predetermined by experimentation or simulation. For example, if the front motor 23 and the rear motor 28 are of the same type and the electric vehicle 100 is traveling on a flat road at a constant speed, the basic distribution is front wheels:rear wheels = 50:50. The basic distribution may change depending on the specific driving conditions of the electric vehicle 100 (steering conditions, etc.).

[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 is calculated. F1 * This is the front-wheel drive force F according to the basic distribution. F This represents the front motor torque generated at the front wheel 21. The first rear torque target value T R1 * This is the rear-wheel drive force F according to the basic distribution. R This represents the rear torque generated at the rear wheel 26. Below, the first front torque target value T F1 * and the first rear torque target value T R1* The combination is 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 the correction driving force distribution (T F3 * , T R3 * ) for attitude control according to the basic attitude is calculated. In this embodiment, the attitude control calculation unit 43 detects the basic attitude of the electric vehicle 100 based on the seat belt attachment / detachment signal S seat . Also, the correction driving force distribution (T F3 * , T R3 * ) is the combination of the final front torque target value (hereinafter, the third front torque target value T F3 * ) for attitude control according to the basic attitude of the electric vehicle 100 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 sets the distribution of the driving force generated by the front wheels 21 and the rear wheels 26 to either the basic driving force distribution (T F1 * , T R1 * ) or the correction driving force distribution (T F3 * , T R3 * ). For example, when the attitude control is on by setting or 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 correction driving force distribution (T F3 * , T R3 *) is set. On the other hand, when attitude control is turned off due to settings, etc., or when the execution of attitude control is not permitted, the drive force setting unit 44 sets the drive force distribution of the front wheels 21 and rear wheels 26 to the basic drive force distribution (T F1 * ,T R1 * Set to (T). In this embodiment, for simplicity, it is assumed that attitude control is turned on by settings, etc., or that the execution of attitude control is permitted. That is, below the drive force setting unit 44 sets the drive force distribution of the front wheels 21 and the rear wheels 26 to corrected drive force distribution (T F3 * ,T R3 * It shall be set to ).

[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. The first front torque target value T commands the basic driving force. F1 * When this is input, the front motor control unit 45 controls the front motor 23 to set the first front torque target value T F1 * This generates the corresponding front torque. Meanwhile, a third front torque target value T commands the corrective driving force for attitude control. F3 * When this is input, the front motor control unit 45 controls the front motor 23 to set the third front torque target value T F3 * This generates corresponding front torque. This results in front-wheel drive force F F It is controlled to either the basic driving force or the compensatory 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. The first rear torque target value T commands the basic driving force. R1 * When this is input, the rear motor control unit 46 controls the rear motor 28 to set the first rear torque target value TR1 * This generates the corresponding rear torque. Meanwhile, a third rear torque target value T commands the corrective driving force for attitude control. R3 * When this is input, the rear motor control unit 46 controls the rear motor 28 to set the third rear torque target value T R3 * This generates rear torque corresponding to the rear-wheel drive force F R It is controlled to either the basic driving force or the compensatory driving force.

[0044] The front motor control unit 45 and the rear motor control unit 46 control the basic driving force distribution (T F1 * ,T R1 * ) or corrected drive force distribution (T F3 * ,T R3 * A drive wheel control unit is configured to control (drive) the front wheels 21 and rear wheels 26 in accordance with the above.

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

[0046] The first calculation unit 51 determines the attitude control drive force distribution (T) which is a drive force distribution that controls the longitudinal attitude of the electric vehicle 100 when the electric vehicle 100 is accelerating or decelerating. F2 * , T R2 * The first calculation unit 51 calculates the driving force distribution for attitude control (T F2 * , T R2 * The configuration for calculating ) includes a basic pitch correction unit 53.

[0047] The basic pitch correction unit 53 controls the attitude control drive force distribution (T) which is a drive force distribution that controls the attitude in the longitudinal direction when the electric vehicle 100 is accelerating or decelerating. F2 * ,T R2* This is a drive force distribution calculation unit that calculates the drive force distribution for attitude control (T) regardless of the basic attitude of the electric vehicle 100, assuming that the electric vehicle 100 maintains a standard attitude when stationary. F2 * , T R2 * ) is calculated. Therefore, the driving force distribution for attitude control (T F2 * , T R2 * ) is a front torque target value (hereinafter referred to as the second front torque target value T) for attitude control, assuming that the electric vehicle 100 maintains a standard posture when stopped. F2 * ) and the rear torque target value (hereinafter referred to as the second rear torque target value T) R2 * This is a combination of the following. Specifically, the basic pitch correction unit 53 adjusts the pitch angle θ based on, for example, a predetermined vehicle model of the electric vehicle 100. P The target pitch angle (hereinafter referred to as the target pitch angle θ) P * The basic driving force distribution (T F1 * ,T R1 * By correcting the driving force distribution for attitude control (T F2 * , T R2 * ) is calculated.

[0048] In other words, the attitude control performed by the electric vehicle 100 in this embodiment is the actual pitch angle θ that occurs. P Regardless of the vehicle model, this is done by feedforward control, which corrects (adjusts) the power distribution based on the vehicle model.

[0049] The second calculation unit 52 detects the basic posture of the electric vehicle 100 and, based on the detected basic posture, determines the above-mentioned attitude control drive force distribution (T F2 * , T R2 * By correcting ), the corrected drive force distribution (TF3 * ,T R3 * The second calculation unit 52 comprises a basic posture detection unit 54, a correction coefficient calculation unit 55, and a center of gravity correction unit 56 for this purpose.

[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 seat belt fastening / unfastening signal S seat Based on this, the basic posture of the electric vehicle 100 is detected. Specifically, the presence or absence of an occupant in each seat is substantially determined by the basic posture of the electric vehicle 100 (center of gravity after transition O G Since this is information that determines the position, the basic posture detection unit 54 receives the seat belt fastening / unfastening signal S. seat Based on this, the system detects whether or not there is an occupant in each seat. The basic posture detection unit 54 then outputs the number of occupants in the front seats (driver's seat and passenger seat) and the rear seats as information representing the basic posture of the electric vehicle 100.

[0051] The correction coefficient calculation unit 55 calculates the drive force distribution for attitude control (T F2 * , T R2 * The correction coefficient K used to correct the ) is calculated. 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 rear seats, based on Table 1 below. In Table 1, "α" is a predetermined value determined in advance by fitting through experiments or simulations, etc.

[0052] [Table 1]

[0053] The center of gravity correction unit 56 adjusts the center of gravity O according to the basic posture. G The amount by which the forward or backward movement occurs determines the drive force distribution for attitude control (T F2 * , T R2 *By performing a center of gravity correction that corrects the ratio of the driving force distribution between the front wheels 21 and the rear wheels 26 in the total center of gravity, the corrected driving force distribution (T F3 * ,T R3 * ) is calculated.

[0054] In this embodiment, the center of gravity correction unit 56 first calculates the attitude control driving force distribution (T) based on the following formula (1). F2 * , T R2 * The ratio of the driving force distributed to the rear wheels 26 in the following configuration (hereinafter referred to as the distribution ratio) D R Calculate the percentage (%).

[0055]

number

[0056] Subsequently, the center of gravity correction unit 56 uses the correction coefficient K according to the following formula (2) to determine the distribution ratio D of the rear wheels 26. R The corrected ratio of the driving force distribution to the rear wheels 26 (hereinafter referred to as the corrected distribution ratio) D is then calculated. R Calculate the '(%)'. This corrected distribution ratio D R ′ represents the ratio of drive force distribution that controls the forward and backward posture while being corrected according to the basic posture.

[0057]

number

[0058] Then, the center of gravity correction unit 56 corrects the driving force distribution (T) according to the following equations (3) and (4). F3 * ,T R3 * The centroid correction unit 56 calculates the correction distribution ratio D. R ′ Accordingly, the drive force distribution for attitude control (T F2 * , T R2 * The power is redistributed to the front wheel 21 and rear wheel 26.

[0059]

number

[0060] As can be seen from the setting of the correction coefficient K, the corrected driving force distribution (T) calculated as described above is F3 * ,T R3 * ) is the attitude control drive force distribution (T F2 * , T R2 * ) results in an increased distribution of driving force to the front wheels 21. Also, when the basic posture is tilted backward compared to the standard posture, the corrected driving force distribution (T F3 * ,T R3 * ) is the driving force distribution for attitude control (T F2 * , T R2 * This results in a distribution that increases the distribution of driving force to the rear wheels 26.

[0061] <effect> The following describes the operation related to attitude control of the electric vehicle 100 configured as described above.

[0062] Figure 6 is a flowchart showing the operation related to attitude control of the electric vehicle 100. As shown in Figure 6, in step S10, the basic distribution calculation unit 42 calculates the basic driving force distribution (TQ) based on the total driving force TQ. F1 * ,T R1 * Next, in step S11, the basic pitch correction unit 53 calculates the basic driving force distribution (T) based on the vehicle model. F1 * ,T R1 * ) from the driving force distribution for attitude control when the electric vehicle 100 is stationary and maintaining a standard posture (T F2 * , T R2* ) is calculated.

[0063] On the other hand, in step S12, the basic posture detection unit 54 receives the seat belt fastening / unfastening signal S seat The basic posture detection unit 54 obtains the seat belt fastening / unfastening signal S. seat Based on this, the basic posture of the electric vehicle 100 is detected by identifying the number of passengers in the front and rear seats. Then, in step S14, the correction coefficient calculation unit 55 calculates a correction coefficient K based on the basic posture of the electric vehicle 100, i.e., the number of passengers in the front and rear seats. Subsequently, in step S15, the center of gravity correction unit 56 uses the correction coefficient K to determine the driving force distribution for posture control (T F2 * , T R2 * By correcting the ratio of the driving force distribution between the front wheels 21 and the rear wheels 26 in the total force distribution, the corrected driving force distribution (T F3 * ,T R3 * ) is calculated. Then, in step S16, the front motor control unit 45 and the rear motor control unit 46 calculate the corrected drive force distribution (T F3 * ,T R3 * The front motor 23 and rear motor 28 are operated according to the above, thereby driving the front wheels 21 and rear wheels 26.

[0064] Corrected drive force distribution (T F3 * ,T R3 * ) is the center of gravity O according to the basic posture G The corrected drive force distribution for attitude control is based on the transition. F3 * ,T R3 * By driving the front wheels 21 and rear wheels 26 according to the above, the electric vehicle 100 assumes its basic posture and transitions to a center of gravity O G Around the pitch angle θ PA precise moment is generated for control. As a result, according to the attitude control of the electric vehicle 100 described above, the attitude of the electric vehicle 100 converges to the target attitude during acceleration or deceleration, regardless of the number of occupants or their specific riding positions. The target attitude during acceleration or deceleration is, for example, the standard attitude (θ P ≈0) or the basic stance, which is the practical initial position.

[0065] [Second Embodiment] In the first embodiment described above, the basic posture detection unit 54 receives the seat belt fastening / unfastening signal S. seat Based on this, the basic posture of the electric vehicle 100 is detected by identifying the number of passengers in the front and rear seats, but is not limited to this. The basic posture detection unit 54 determines the front vehicle height H F2 and rear vehicle height H R2 , or the difference ΔH FR (=H F2 -H R2 By identifying the front vehicle height H, the basic posture of the electric vehicle 100 can be detected. In the second embodiment, the front vehicle height H F2 Rear ride height H R2 The difference ΔH FR This section describes an example of detecting the basic attitude of an electric vehicle 100 by identifying a specific element.

[0066] Figure 7 is a block diagram showing the configuration of the attitude control calculation unit 43 in the second embodiment. As shown in Figure 7, the configuration of the second calculation unit 52 in the attitude control calculation unit 43 of the second embodiment differs from that of the first embodiment. Specifically, the attitude control calculation unit 43 of the second embodiment includes a stationary detection unit 201, a basic attitude detection unit 202 and a correction coefficient calculation unit 203 that differ from those in the first embodiment, and a center of gravity correction unit 56 similar to that of the first embodiment.

[0067] The stop detection unit 201 uses the vehicle speed VSP and the road surface gradient φ to detect the vehicle speed. LS Based on this, the system detects whether the electric vehicle 100 is stopped on a flat road. The stop detection unit 201 detects whether the vehicle speed VSP is zero within a predetermined error range (VSP ≈ 0) and the road surface gradient φ LS When (φ) is zero within a predetermined range of error, LS≈0), it is determined that the electric vehicle 100 is stopped on a flat road.

[0068] The basic posture detection unit 202 detects when the vehicle is stopped on a flat road, and then detects the suspension stroke signal S sus The basic attitude detection unit 202 then obtains the suspension stroke signal S. sus Based on this, the front vehicle height H F2 and rear vehicle height H R2 , or the difference ΔH FR By calculating this, the attitude of the electric vehicle 100 when it is stationary is detected. Here, it is assumed that the electric vehicle 100 is in a basic attitude different from the standard attitude. Front vehicle height H F2 and rear vehicle height H R2 , or the difference ΔH FR According to the structural model of the vehicle body, the suspension stroke signal S sus It can be calculated from. In this embodiment, the basic attitude detection unit 202 determines the front vehicle height H F2 Rear ride height H R2 The difference ΔH FR Perform the calculation.

[0069] The correction coefficient calculation unit 203 calculates the drive force distribution for attitude control (T F2 * , T R2 * The correction coefficient K used to correct the front vehicle height H is calculated. This is the same as the correction coefficient calculation unit 203 of the first embodiment. However, the correction coefficient calculation unit 203 of the second embodiment uses F2 Rear ride height H R2 The difference ΔH FR Based on this, the correction coefficient K is calculated. Front vehicle height H F2 Rear ride height H R2 The difference ΔH FR The relationship between the correction coefficient K and the given value is predetermined by fitting through experiments or simulations.

[0070] Figure 8 shows the front vehicle height H. F2 Rear ride height H R2 The difference ΔH FRThis graph illustrates the relationship between the correction coefficient K and the front vehicle height H. As shown in Figure 8, in this embodiment, the correction coefficient calculation unit 203 calculates, for example, the front vehicle height H F2 Rear ride height H R2 The difference ΔH FR The correction coefficient K is predetermined to increase or decrease proportionally to the difference ΔH. FR ΔH FR If the value is ′, the corresponding correction coefficient K is K′. The properties of the correction coefficient K calculated by the correction coefficient calculation unit 203 are the same as in the first embodiment.

[0071] In this way, the front vehicle height H F2 Rear ride height H R2 The difference ΔH FR By defining the relationship between the correction coefficient K and the center of gravity correction unit 56, the corrected driving force distribution (T F3 * ,T R3 * ) is the attitude control drive force distribution (T F2 * , T R2 * ) results in an increased distribution of driving force to the front wheels 21. Also, when the basic posture is tilted backward compared to the standard posture, the corrected driving force distribution (T F3 * ,T R3 * ) is the driving force distribution for attitude control (T F2 * , T R2 * This results in a distribution that increases the distribution of driving force to the rear wheels 26.

[0072] Figure 9 is a flowchart showing the operation related to attitude control in the second embodiment. As shown in Figure 9, in step S20, the basic distribution calculation unit 42 calculates the basic driving force distribution (TQ) based on the total driving force TQ. F1 * ,T R1 * Next, in step S21, the basic pitch correction unit 53 calculates the basic driving force distribution (T) based on the vehicle model. F1 *,T R1 * ) from the driving force distribution for attitude control when the electric vehicle 100 is stationary and maintaining a standard posture (T F2 * , T R2 * ) is calculated.

[0073] Meanwhile, in step S22, the stop detection unit 201 detects the vehicle speed VSP and the road surface gradient φ LS The system obtains the vehicle speed VSP. Then, in step S23, the station detection unit 201 detects whether the electric vehicle 100 is stationary based on the vehicle speed VSP. If the vehicle speed VSP is substantially zero and it is determined that the electric vehicle 100 is stationary, the system proceeds to step S24. In step S24, the station detection unit 201 obtains the road surface gradient φ LS Based on this, the system detects whether the road surface on which the electric vehicle 100 is parked is flat. If it is detected that the road surface on which the electric vehicle 100 is parked is flat, the system proceeds to step S25, where the basic posture detection unit 202 receives the suspension stroke signal S sus Obtain it.

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

[0075] Then, in step S27, the correction coefficient calculation unit 203 calculates the front vehicle height H F2 Rear ride height H R2 The difference ΔH FRBased on this, the correction coefficient K is calculated. If 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 a flat road, the process proceeds to step S30 and the previous correction coefficient K is maintained.

[0076] Subsequently, in step S28, the center of gravity correction unit 56 uses the correction coefficient K to determine the attitude control drive force distribution (T F2 * , T R2 * By correcting the ratio of the driving force distribution between the front wheels 21 and the rear wheels 26 in the total force distribution, the corrected driving force distribution (T F3 * ,T R3 * ) is calculated. Then, in step S29, the front motor control unit 45 and the rear motor control unit 46 calculate the corrected drive force distribution (T F3 * ,T R3 * The front motor 23 and rear motor 28 are operated according to the above, thereby driving the front wheels 21 and rear wheels 26.

[0077] As described above, the front vehicle height H F2 and rear vehicle height H R2 , or the difference ΔH FR When detecting the basic posture of the electric vehicle 100 by identifying the corrected drive force distribution (T F3 * ,T R3 * ) is the center of gravity O according to the basic posture G This results in a corrected and accurate attitude control drive force distribution based on the transition. Therefore, the corrected drive force distribution (T F3 * ,T R3 * By driving the front wheels 21 and rear wheels 26 according to the above, the center of gravity O transitions to the basic posture. G Around the pitch angle θ PA precise moment is generated for control. As a result, according to the attitude control of the second embodiment described above, the attitude of the electric vehicle 100 converges to the target attitude during acceleration or deceleration, similar to the first embodiment.

[0078] Also, as mentioned above, the front vehicle height H F2 and rear vehicle height H R2 , or the difference ΔH FR When detecting the basic posture of the electric vehicle 100 by identifying the number of occupants and their specific riding positions, the corrected driving force distribution (T) can be determined even if the basic posture of the electric vehicle 100 changes depending on the amount and position of the luggage loaded onto the electric vehicle 100. F3 * ,T R3 * ) is the center of gravity O according to its basic posture G This results in a precise attitude control drive force distribution corrected based on the transition. Therefore, the second embodiment makes it easier to converge the attitude of the electric vehicle 100 to a target attitude during acceleration or deceleration.

[0079] In the second embodiment described above, the suspension stroke signal S sus Based on this, the basic attitude of the electric vehicle 100 is detected, but it is not limited to this, and the basic attitude of the electric vehicle 100 may be detected using other parameters. For example, the pitch angle θ of the electric vehicle 100 is P Since it is possible to obtain the pitch angle θ, the basic attitude detection unit 202 P The basic posture of the electric vehicle 100 may be detected directly by the suspension stroke signal S. sus Instead, pitch angle θ P When using, the pitch angle θ P This should be acquired when the electric vehicle 100 is stopped on a flat road, similar to the second embodiment described above.

[0080] As described above, the control methods for electric vehicles according to the first and second embodiments are control methods for electric vehicles 100 that perform attitude control to control the attitude in the longitudinal direction by adjusting the driving force distribution of the front wheels 21 and rear wheels 26, which are the drive wheels. In this electric vehicle control method, the basic attitude, which is the actual attitude in the longitudinal direction when the electric vehicle 100 is stopped, is detected. Furthermore, when the electric vehicle 100 accelerates or decelerates, the driving force distribution for attitude control (T) is set to control the attitude in the longitudinal direction. F2 * ,T R2 * The following is calculated: Then, the drive force distribution for attitude control (T) is calculated based on the basic attitude. F2 * ,T R2 * By correcting ), the corrected drive force distribution (T F3 * ,T R3 * ) is calculated, and this corrected drive force distribution (T F3 * ,T R3 * The drive wheels (21, 26) are controlled according to the following.

[0081] In this way, based on the basic posture of the electric vehicle 100, the driving force distribution for posture control (T F2 * ,T R2 * By correcting ), the corrected drive force distribution (T F3 * ,T R3 * ) calculates the corrected drive force distribution (T F3 * ,T R3 * ) is the center of gravity O according to the basic posture G This results in a corrected and accurate attitude control drive force distribution based on the transition. Therefore, as described above, the corrected drive force distribution (T F3 * ,T R3 * By driving the front wheels 21 and rear wheels 26 according to the above, the electric vehicle 100 assumes its basic posture and transitions to a center of gravity OG Around the pitch angle θ P A precise moment is generated for control. As a result, during acceleration or deceleration, the attitude of the electric vehicle 100 converges to the target attitude.

[0082] In the control method for electric vehicles according to the first and second embodiments described above, when the basic posture is tilted forward relative to a predetermined standard posture, the attitude control driving force distribution (T F2 * ,T R2 * ) Corrected drive force distribution (T F3 * ,T R3 * ) is calculated. Also, if the basic posture is tilted backward relative to the standard posture, the attitude control drive force distribution (T F2 * ,T R2 * ) Corrected drive force distribution (T F3 * ,T R3 * The calculation is performed.

[0083] The corrected drive force distribution calculated in this way (T F3 * ,T R3 * ) is the center of gravity O that transitioned with the electric vehicle 100 in its basic position. G Around the pitch angle θ P It is easy to generate the precise moment needed for control. Therefore, during acceleration or deceleration, the attitude of the electric vehicle 100 tends to converge to the target attitude.

[0084] In the control methods for electric vehicles according to the first and second embodiments described above, a correction coefficient K based on the basic attitude is calculated. In addition, the driving force distribution for attitude control (T F2 * ,T R2 * The ratio of the distribution of driving force between the front wheels 21 and the rear wheels 26 in the total (D R The allocation ratio (D) is calculated.R Using the ) and correction coefficient K, the forward and backward attitude is controlled, and the corrected distribution ratio (D) is a distribution ratio corrected according to the basic attitude. R The ') is calculated. Then, the corrected distribution ratio (D R According to ′), the driving force distribution for attitude control (T F2 * ,T R2 * By redistributing the force to the front wheels 21 and rear wheels 26, the corrected drive force distribution (T F3 * ,T R3 * The calculation is performed.

[0085] This corrected drive force distribution (T F3 * ,T R3 * According to the calculation, when the basic posture is tilted forward, the attitude control drive force distribution (T F2 * ,T R2 * ) increases the distribution of driving force to the front wheels 21, and when the posture is tilted backward, the driving force distribution for posture control (T F2 * ,T R2 * ) allows for increased distribution of driving force to the rear wheels 26. Corrected driving force distribution (T F3 * ,T R3 * ) is the center of gravity O that transitioned with the electric vehicle 100 in its basic position. G Around the pitch angle θ P This makes it easier to generate the precise moment needed for control. As a result, during acceleration or deceleration, the attitude of the electric vehicle 100 tends to converge to the target attitude.

[0086] In the electric vehicle control methods according to the first and second embodiments described above, attitude control is performed by feedforward control, which corrects the driving force distribution based on the vehicle model.

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

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

[0089] Thus, when the electric vehicle 100 is stopped on a flat road, the front vehicle height H F2 and rear vehicle height H R2 Based on this, if the basic posture is detected, accurate corrective driving force distribution (T) will be performed regardless of the basic posture or the factors causing its change. F3 * ,T R3 * ) is easily calculated.

[0090] In particular, in the control method for the electric vehicle according to the second embodiment described above, when the electric vehicle 100 is stopped on a flat road, the suspension stroke (S sus ) is obtained, and the stroke (S) of this suspension (31,32) sus Based on the above, the front vehicle height H F2 Rear ride height H R2 , or front vehicle height H F2 Rear ride height H R2 The difference ΔH FR By identifying the , the basic posture is detected.

[0091] Thus, by using the stroke of the suspension (31,32), the front ride height H F2 Rear ride height HR2 or the height of the vehicle ahead H F2 and the height of the vehicle behind H R2 the difference ΔH FR is accurately specified.

[0092] Also, the control method for the electric vehicle according to the second embodiment acquires the pitch angle θ of the electric vehicle 100 when the electric vehicle 100 is stopped on a flat road, and can be modified to a form that detects the basic posture based on the pitch angle θ. P Based on the pitch angle θ P the basic posture can be detected.

[0093] Thus, the basic posture of the electric vehicle 100 can also be accurately detected by the pitch angle θ when the vehicle is stopped on a flat road. P the basic posture of the electric vehicle 100 can be accurately detected.

[0094] In the control method for the electric vehicle according to the first embodiment, the attachment / detachment state of the seat belt is detected, and the basic posture is detected based on the attachment / detachment state of the seat belt. In this way, when detecting the basic posture of the electric vehicle 100 according to the attachment / detachment state of the seat belt, it is particularly easy to accurately detect the basic posture of the electric vehicle 100 when the posture changes depending on the number of passengers and the seating position. Also, regardless of the vehicle speed VSP and the road surface gradient φ LS there is also an advantage that it is easy to accurately detect the basic posture of the electric vehicle 100.

[0095] The control device for the electric vehicle according to the first and second embodiments is a control device (controller 12) for the electric vehicle 100 that performs attitude control to control the attitude in the front-rear direction by adjusting the driving force distribution between the front wheels 21 and the rear wheels 26, which are the driving wheels. This control device (controller 12) includes a basic posture detection unit (54, 202) that detects the basic posture, which is the attitude in the front-rear direction when the electric vehicle 100 is stopped, and a driving force distribution for attitude control (T F2 * , T R2 * ) that calculates the driving force distribution for attitude control (T F2* ,T R2 * By correcting ), the corrected drive force distribution (T F3 * ,T R3 * A correction unit (56) that calculates the corrected driving force distribution (T F3 * ,T R3 * The system includes a drive wheel control unit (45, 46) that controls the drive wheels (21, 26) according to the following:

[0096] In this way, based on the basic posture of the electric vehicle 100, the driving force distribution for posture control (T F2 * ,T R2 * By correcting ), the corrected drive force distribution (T F3 * ,T R3 * ) calculates the corrected drive force distribution (T F3 * ,T R3 * ) is the center of gravity O according to the basic posture G This results in a corrected and accurate attitude control drive force distribution based on the transition. Therefore, the corrected drive force distribution (T F3 * ,T R3 * By driving the front wheels 21 and rear wheels 26 with ), the electric vehicle 100 transitions to its basic posture and center of gravity O G Around the pitch angle θ P A precise moment is generated for control. As a result, during acceleration or deceleration, the attitude of the electric vehicle 100 converges to the target attitude.

[0097] The control programs for the electric vehicle according to the first and second embodiments described above are control programs for an electric vehicle 100 that perform attitude control to control the attitude in the longitudinal direction by adjusting the driving force distribution between the front wheels 21 and the rear wheels 26, which are the drive wheels. This control program for the electric vehicle controls the control device (controller 12) of the electric vehicle 100, and 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; and an attitude control driving force distribution (T) which is the driving force distribution that controls the attitude in the longitudinal direction when the electric vehicle 100 is accelerating or decelerating. F2 * ,T R2 * A drive force distribution calculation unit (53) calculates the drive force distribution for attitude control (T F2 * ,T R2 * By correcting ), the corrected drive force distribution (T F3 * ,T R3 * Correction unit (56) that calculates ) and corrected driving force distribution (T F3 * ,T R3 * This controls the drive wheels (21, 26) according to the specified parameters, and functions as a drive wheel control unit (45, 46). This control program can be stored and provided on any storage medium.

[0098] Although embodiments of the present invention have been described above, the configurations described in the above embodiments and each of the modifications 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.

Claims

1. A control method for an electric vehicle that controls the attitude in the longitudinal direction by adjusting the distribution of driving force between the front and rear wheels, which are the drive wheels, The basic posture, which is the actual forward and backward orientation of the electric vehicle when it is stopped, is detected. When the electric vehicle accelerates or decelerates, the attitude control drive force distribution, which is the drive force distribution that controls the attitude in the longitudinal direction, is calculated. By correcting the attitude control drive force distribution based on the basic attitude, the corrected drive force distribution is calculated. The drive wheels are controlled according to the corrected drive force distribution. If the basic posture is tilted forward relative to a predetermined standard posture, the corrected drive force distribution is calculated by increasing the distribution of drive force to the front wheels relative to the drive force distribution for posture control. If the basic posture is tilted backward relative to the standard posture, the corrected drive force distribution is calculated by increasing the distribution of drive force to the rear wheels relative to the drive force distribution for posture control. A method for controlling electric vehicles.

2. A control method for an electric vehicle according to claim 1, A correction coefficient is calculated based on the aforementioned basic posture. The distribution ratio of the driving force of the front wheels and the rear wheels in the aforementioned driving force distribution for attitude control is calculated, Using the aforementioned distribution ratio and the correction coefficient, the posture in the front-to-back direction is controlled, and a corrected distribution ratio, which is the distribution ratio corrected according to the basic posture, is calculated. The corrected drive force distribution is calculated by redistributing the attitude control drive force distribution to the front wheels and the rear wheels according to the corrected distribution ratio. A method for controlling electric vehicles.

3. A control method for an electric vehicle according to claim 1, The attitude control described above is performed by feedforward control, which corrects the driving force distribution based on the vehicle model. A method for controlling electric vehicles.

4. A control method for an electric vehicle according to claim 1, The basic posture is detected based on the front and rear vehicle heights when the electric vehicle is stopped on a flat road. A method for controlling electric vehicles.

5. A control method for an electric vehicle according to claim 4, When the electric vehicle is stopped on a flat road, the suspension stroke is obtained. The basic posture is detected by determining the front vehicle height, the rear vehicle height, or the difference between the front vehicle height and the rear vehicle height based on the suspension stroke. A method for controlling electric vehicles.

6. A control method for an electric vehicle according to claim 4, When the electric vehicle is stopped on a flat road, the pitch angle of the electric vehicle is obtained. Based on the pitch angle, the basic attitude is detected. A method for controlling electric vehicles.

7. A control method for an electric vehicle according to claim 1, The system detects the fastening / unfastening status of the seat belt. Based on the state of the seat belt being fastened or unfastened, the basic posture is detected. A method for controlling electric vehicles.

8. A control device for an electric vehicle that controls the attitude in the longitudinal direction by adjusting the distribution of driving force between the front and rear wheels, which are the drive wheels, A basic attitude detection unit detects the basic attitude, which is the actual forward and backward orientation of the electric vehicle when it is stopped. A drive force distribution calculation unit calculates a drive force distribution for attitude control, which is the drive force distribution that controls the attitude in the longitudinal direction when the electric vehicle accelerates or decelerates. A correction unit calculates a corrected drive force distribution by correcting the drive force distribution for attitude control based on the basic attitude, A drive wheel control unit that controls the drive wheels according to the corrected drive force distribution, Equipped with, If the basic posture is tilted forward relative to a predetermined standard posture, the corrected drive force distribution is calculated by increasing the distribution of drive force to the front wheels relative to the drive force distribution for posture control. If the basic posture is tilted backward relative to the standard posture, the corrected drive force distribution is calculated by increasing the distribution of drive force to the rear wheels relative to the drive force distribution for posture control. Control device for electric vehicles.

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