Vehicle control device and vehicle control method

Abstract

A vehicle control device according to an embodiment of the present disclosure is a device capable of controlling a vehicle that travels under motor driving. The vehicle control device comprises a control unit capable of deriving a target torque by adding a periodically varying variable torque to a required torque according to an acceleration demand, and controlling the torque of a motor on the basis of the derived target torque. The control unit is capable of varying the gain of the variable torque in accordance with the gear stage when the vehicle is in a transient state different from a steady state in which the acceleration and angular velocity of the vehicle are at or below predetermined values.

Description

Technical Field

[0004] , , ,

[0005] , , , , , ,

[0001] The present disclosure relates to a vehicle control device mounted on a vehicle and a vehicle control method executed in the vehicle control device.

Background Art

[0002] Conventionally, various techniques for operating a vehicle more safely have been proposed (see, for example, Patent Documents 1 and 2).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

[0004] A vehicle control device according to an embodiment of the present disclosure is a device capable of controlling a vehicle that travels by motor drive. This vehicle control device includes a control unit capable of deriving a target torque by adding a fluctuating torque that periodically fluctuates to a required torque according to an acceleration requirement, and controlling the torque of the motor based on the derived target torque. This control unit can change the gain of the fluctuating torque according to the gear stage when in a transient state different from a steady state where the acceleration and angular velocity of the vehicle are below a predetermined value. and the vehicle is turning When, it is possible to change the gain of the fluctuating torque according to the gear stage. A vehicle control device according to one embodiment of the present disclosure is a device capable of controlling a vehicle that is driven by a motor. This vehicle control device includes a control unit capable of deriving a target torque by adding a periodically fluctuating torque to a required torque corresponding to an acceleration request, and controlling the motor torque based on the derived target torque. This control unit is capable of changing the gain of the fluctuating torque according to the gear stage when the vehicle is in a transient state different from a steady state in which the vehicle's acceleration and angular velocity are below a predetermined value. This control unit is capable of setting the gain of the fluctuating torque in the first gear stage to a first gain when the required torque in the transient state is regenerative torque, and setting the gain of the fluctuating torque in the first gear stage to a second gain that is smaller than the first gain when the required torque in the transient state is power torque.

[0005] A vehicle control method according to an embodiment of the present disclosure is a method capable of controlling a vehicle that travels by motor drive. This vehicle control method includes the following two. (A) Deriving a target torque by adding a fluctuating torque that periodically fluctuates to a required torque according to an acceleration requirement, and performing torque control of the motor based on the derived target torque (B) Transient states different from the steady state in which the vehicle's acceleration and angular velocity are below a predetermined value. and the vehicle is turning At that time, the gain of the fluctuating torque is changed according to the gear stage. A vehicle control method according to one embodiment of the present disclosure is a method capable of controlling a vehicle that is driven by a motor. This vehicle control method includes the following three elements: (C) A target torque is derived by adding a periodically fluctuating torque to the required torque in response to the acceleration requirement, and the motor torque is controlled based on the derived target torque. (D) When the vehicle is in a transient state different from a steady state in which the vehicle's acceleration and angular velocity are below a predetermined value, the gain of the fluctuating torque is changed according to the gear position. (E) When the required torque in the transient state is regenerative torque, the gain of the fluctuating torque in the first gear stage is set to the first gain; when the required torque in the transient state is motoring torque, the gain of the fluctuating torque in the first gear stage is set to a second gain that is smaller than the first gain. [Brief explanation of the drawing]

[0006] The accompanying drawings are provided for further understanding of this disclosure and are incorporated herein and constitute part of this specification. The drawings illustrate one embodiment and, together with the specification, serve to illustrate the principles of this disclosure.

[0007] [Figure 1] Figure 1 is a diagram showing an example of a functional block of a vehicle equipped with a vehicle control device according to one embodiment of the present disclosure. [Figure 2] Figure 2(A) shows an example of the waveform of the required torque (regenerative torque). Figure 2(B) shows an example of the waveform of the fluctuating torque. Figure 2(C) shows an example of the waveform of the target torque. [Figure 3] Figure 3(A) shows an example of the waveform of the required torque (motor torque). Figure 3(B) shows an example of the waveform of the fluctuating torque. Figure 3(C) shows an example of the waveform of the target torque. [Figure 4] Figure 4 is a diagram illustrating an example of the procedure for deriving the fluctuating torque in the travel control unit shown in Figure 1. [Figure 5] Figure 5 illustrates an example of the procedure for setting the gain of the fluctuating torque derived using the steps in Figure 4, and an example of the procedure for deriving the target torque. [Figure 6] Figure 6 shows an example of how a vehicle navigates a corner. [Figure 7] Figure 7 shows an example of the target torque waveform when the vehicle passes through the corner shown in Figure 6. [Modes for carrying out the invention]

[0008] In vehicles driven by an electric motor, the motor output is smoother than the engine output. Therefore, a smooth driving feel can be obtained in all driving conditions, such as driving straight, changing lanes, and driving around curves. However, while such a smooth driving feel is obtained, the driver has difficulty perceiving the grip between the tires and the road surface when turning (for example, when cornering, turning right or left at an intersection, or changing lanes), and it is difficult to feel a sense of security or steering feedback. It is desirable to provide a vehicle control device and vehicle control method that can give the driver a sense of security and steering feedback when turning.

[0009] Hereinafter, several exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The following description is intended to illustrate specific examples of the present disclosure and should not be construed as limiting the disclosure. For example, elements such as numerical values, shapes, materials, parts, the location of each part, and the method of connecting each part are merely examples and should not be construed as limiting the disclosure. Furthermore, in the following exemplary embodiments, components not described in separate sections based on the highest-level concepts of the present disclosure are optional and may be provided as needed. The drawings are schematic and are not intended to be to scale. Throughout this specification and the drawings, components having substantially the same function and substantially the same configuration are denoted by the same reference numerals, and redundant descriptions are omitted. Furthermore, components not directly related to an embodiment of the present disclosure are not shown in the drawings.

[0010] <1. Embodiment> [Example Configuration] Figure 1 shows a schematic configuration example of a vehicle 1 equipped with a control unit 20 according to one embodiment of the present disclosure. The control unit 20 corresponds to one specific example of the "control unit" of the present disclosure. The vehicle 1 is capable of moving by motor drive. The vehicle 1 includes, for example, a sensor unit 10, a control unit 20, a storage unit 30, a control flag input unit 40, and a motor 50, as shown in Figure 1.

[0011] The sensor unit 10 is configured to include various sensors mounted on the vehicle 1. The sensor unit 10 has, for example, an accelerator operation amount sensor 11, a gear position sensor 12, and a vehicle state amount sensor 13 as shown in FIG. 1. The sensor unit 10 may have sensors other than those described above.

[0012] The accelerator operation amount sensor 11 is capable of detecting the accelerator operation amount from the depression amount of the accelerator pedal. The accelerator operation amount sensor 11 is capable of outputting data (accelerator operation amount data Da) regarding the detected accelerator operation amount to the control unit 20. When the accelerator operation amount data Da is zero, the control unit 20 can regard the acceleration request from the driver as a deceleration request. When the accelerator operation amount data Da is greater than zero, the control unit 20 can regard the acceleration request from the driver as an acceleration request.

[0013] The gear position sensor 12 is a sensor capable of detecting the current gear position. The gear position sensor 12 may be, for example, an input position detection sensor capable of detecting the current gear position by detecting the input position of the shift lever. The gear position sensor 12 may be, for example, a signal detection sensor capable of detecting the current gear position by detecting a signal output by paddle shift operation. The gear position sensor 12 is capable of outputting data (gear position data Dg) regarding the detected gear position to the control unit 20.

[0014] For example, when the gear position is the first gear, D1 is output as the gear position data Dg from the gear position sensor 12. For example, when the gear position is the second gear, D2 is output as the gear position data Dg from the gear position sensor 12. For example, when the gear position is the third gear, D3 is output as the gear position data Dg from the gear position sensor 12. For example, when the gear position is the fourth gear, D4 is output as the gear position data Dg from the gear position sensor 12.

[0015] The vehicle state quantity sensor 13 can detect a vehicle state quantity, which is information indicating the state of the vehicle 1. The vehicle state quantity sensor 13 can output time-series data (vehicle state quantity data) about the detected vehicle state quantity to the control unit 20. The vehicle state quantity sensor 13 is configured to include, as sensors capable of detecting the vehicle state quantity, for example, a vehicle speed sensor, an acceleration sensor, an angular velocity sensor, a steering angle sensor, and a steering torque sensor.

[0016] The vehicle speed sensor can detect the speed (vehicle speed) of the vehicle 1. The vehicle speed sensor can output time-series data (vehicle speed data) about the detected vehicle speed to the control unit 20. The acceleration sensor can detect the acceleration applied to the vehicle 1. The acceleration sensor can output time-series data (acceleration data) about the detected accelerations in three directions (front-rear acceleration, left-right acceleration, up-down acceleration) to the control unit 20. The angular velocity sensor can detect the angular velocity of the vehicle 1. The angular velocity sensor can output time-series data (angular velocity data) about the detected three angular velocities (yaw angular velocity, roll angular velocity, pitch angular velocity) to the control unit 20.

[0017] The steering angle sensor can detect the steering angle (steering wheel angle) of the steering wheel of the vehicle 1. The steering angle sensor can output time-series data (steering wheel angle data) about the detected steering wheel angle to the control unit 20. The steering torque sensor can detect the steering torque generated by the driver's steering operation. The steering torque sensor can output time-series data (steering torque data) about the detected steering torque to the control unit 20.

[0018] The control unit 20 is capable of controlling the entire vehicle 1. The control unit 20 is, for example, a so-called ECU (Electronic Control Unit) and is composed of, for example, one or more processors and one or more memories. The control unit 20 may also be composed of, for example, a CPU (Central Processing Unit). In this case, the control unit 20 may be capable of controlling the entire vehicle 1 by, for example, executing a program stored in the memory unit 30.

[0019] The control unit 20 is capable of controlling the vehicle 1, which is driven by a motor. The control unit 20 includes, for example, a driving control unit 21, as shown in Figure 1. The driving control unit 21 is capable of controlling the driving of the vehicle 1 (for example, the torque of the motor 50). The driving control unit 21 includes, for example, a requested torque derivation unit 22, a fluctuating torque derivation unit 23, and a motor torque control unit 24, as shown in Figure 1.

[0020] The requested torque derivation unit 22 is capable of deriving a requested torque Tr in response to an acceleration request. The acceleration request includes the degree of depression of the accelerator pedal, or the variation in the amount of depression of the accelerator pedal, and the gear position, or the variation in the gear position. The acceleration request includes, for example, accelerator operation amount data Da and gear position data Dg. The requested torque derivation unit 22 is capable of deriving the amount of torque (requested torque Tr) that the motor 50 should generate based, for example, the accelerator operation amount data Da and the gear position data Dg. The acceleration request may be made by the driver during manual operation, or by the driving control unit 21 during automatic operation.

[0021] Figure 2(A) shows an example of the time change of the required torque Tr (regenerative torque) obtained when the driver takes their foot off the accelerator pedal while the vehicle 1 is in motion. Figure 2(A) illustrates how the vehicle 1 decelerates over time, and as a result, the required torque Tr (regenerative torque) also decreases over time. The required torque derivation unit 22 can derive the required torque Tr (regenerative torque) that the motor 50 should generate based on the gear stage data Dg, for example, when the accelerator operation amount data Da is zero.

[0022] Figure 3(A) shows an example of the time change in the required torque Tr (motor torque) obtained when the driver presses the accelerator pedal over time. Figure 3(A) illustrates how the vehicle 1 accelerates over time, and as a result, the required torque Tr (motor torque) also increases over time. The required torque derivation unit 22 can derive the required torque Tr (motor torque) that the motor 50 should generate, for example, based on accelerator operation amount data Da and gear stage data Dg.

[0023] The variable torque derivation unit 23 is capable of deriving a periodically fluctuating variable torque Tf (Figures 2(B) and 3(B)). Figures 2(B) and 3(B) show an example of the time change of the variable torque Tf. The variable torque Tf is intended to intentionally change the behavior of the vehicle 1, thereby giving the driver a sense of security and responsiveness to steering during turns (for example, when cornering, turning right or left at an intersection, or changing lanes).

[0024] The fluctuation range of the fluctuating torque Tf is, for example, about 10% of the magnitude of the required torque Tr. The frequency of the fluctuating torque Tf is, for example, 17Hz, 20Hz, or 24Hz. The waveform of the fluctuating torque Tf is, for example, a rectangular or sine wave. The fluctuation range, frequency, and waveform of the fluctuating torque Tf are not limited to those described above. The fluctuating torque derivation unit 23 may be capable of changing at least one of the fluctuation range, frequency, and waveform of the fluctuating torque Tf according to the magnitude of the required torque Tr. The fluctuating torque derivation unit 23 may be capable of keeping at least one of the fluctuation range, frequency, and waveform of the fluctuating torque Tf constant regardless of the magnitude of the required torque Tr.

[0025] The fluctuating torque derivation unit 23 can correct the fluctuating torque Tf based on the input gain G when the motor torque control unit 24 inputs the gain G of the fluctuating torque Tf. For example, the fluctuating torque derivation unit 23 can multiply the fluctuating torque Tf by the gain G and thereby derive a new fluctuating torque (Tf × G). The gain G will be described in detail later.

[0026] The motor torque control unit 24 derives a target torque Tg (Figures 2(C) and 3(C)) by adding a fluctuating torque (Tf or Tf × G) to the required torque Tr, and can control the torque of the motor 50 based on the derived target torque Tg. Figures 2(C) and 3(C) show an example of the time change of the target torque Tg.

[0027] The motor torque control unit 24 can determine whether vehicle 1 is in a steady state or a transient state based on vehicle state data (acceleration data and angular velocity data) obtained from the vehicle state sensor 13, for example. A "steady state" refers to a state in which the acceleration data and angular velocity data are below a predetermined value (threshold). A "steady state" includes constant-speed straight driving. A "steady state" also includes a state in which the vehicle is traveling at a speed within the range recognized as constant-speed straight driving when the steering angle is 0° or a very small angle. A "transient state" means a state different from the "steady state". A "transient state" includes turning (for example, cornering, right / left turns at intersections, lane changes). A "transient state" also includes, for example, steady-state circular turning. When the steering angle is greater than a predetermined value (threshold), vehicle 1 is turning and can be said to be in a "transient state".

[0028] The motor torque control unit 24 can, for example, change the gain G of the fluctuating torque Tf according to the gear stage. The motor torque control unit 24 can, for example, change the gain G of the fluctuating torque Tf according to the gear stage when the vehicle 1 is in a transient state. The motor torque control unit 24 can, for example, set the gain G of the fluctuating torque Tf based on the gear stage data Dg obtained by the gear stage sensor 12.

[0029] The motor torque control unit 24 can, for example, set the gain G of the fluctuating torque Tf when the gear is in 1st gear to G1 (first gain) if the required torque Tr in a transient state is regenerative torque. The motor torque control unit 24 can, for example, set the gain G of the fluctuating torque Tf when the gear is in 2nd gear if the required torque Tr in a transient state is regenerative torque to G2 (first gain). The motor torque control unit 24 can, for example, set the gain G of the fluctuating torque Tf when the gear is in 3rd gear if the required torque Tr in a transient state is regenerative torque to G3 (first gain). The motor torque control unit 24 can, for example, set the gain G of the fluctuating torque Tf when the gear is in 4th gear if the required torque Tr in a transient state is regenerative torque to G4 (first gain). Here, the magnitude of the gain G increases as the gear (gear ratio) decreases. For example, G1 > G2 > G3 > G4 holds true.

[0030] The motor torque control unit 24 can, for example, set the gain G of the fluctuating torque Tf when the gear is in 1st gear to G5 (second gain), which is smaller than G1 (first gain), if the required torque Tr in a transient state is the powering torque. The motor torque control unit 24 can, for example, set the gain G of the fluctuating torque Tf when the gear is in 2nd gear, which is smaller than G2 (first gain), to G6 (second gain). The motor torque control unit 24 can, for example, set the gain G of the fluctuating torque Tf when the gear is in 3rd gear, which is smaller than G3 (first gain), to G7 (second gain). The motor torque control unit 24 can, for example, set the gain G of the fluctuating torque Tf when the gear is in 4th gear, which is smaller than G4 (first gain), if the required torque Tr in a transient state is the powering torque. Here, the magnitude of the gain G increases as the gear ratio decreases. For example, G5 > G6 > G7 > G8 holds true.

[0031] The motor torque control unit 24 can determine, for example, whether or not to add the fluctuating torque Tf to the requested torque Tr based on the control flag 31 described later. For example, when the control flag 31 means the torque fluctuation control mode, the motor torque control unit 24 can derive the target torque Tg by adding the fluctuating torque Tf to the requested torque Tr. The "torque fluctuation control mode" refers to a mode in which torque control is performed by oscillating the target torque Tg at a low frequency (for example, 17Hz, 20Hz, or 24Hz). For example, when the control flag 31 means the normal mode, the motor torque control unit 24 can set the requested torque Tr to the target torque Tg. The "normal mode" refers to a mode in which torque control is performed according to the requested torque Tr without oscillating the target torque Tg at a low frequency.

[0032] The memory unit 30 stores, for example, control flags 31 input from the control flag input unit 40. The memory unit 30 may also store, for example, a program executed by the control unit 20. This program is a program that causes the control unit 20 to execute a series of procedures for controlling the entire vehicle 1. The memory unit 30 is composed of, for example, RAM (Random Access Memory), ROM (Read Only Memory), auxiliary storage device (hard disk, etc.).

[0033] The control flag input unit 40 is capable of receiving input of a control flag 31 from the driver. The control flag input unit 40 is, for example, a paddle shifter attached to the steering wheel. The control flag input unit 40 is capable of storing "1" as the control flag 31 in the memory unit 30 when, for example, the driver presses and holds both the left and right paddle shifters simultaneously. The control flag input unit 40 is capable of storing "0" as the control flag 31 in the memory unit 30 when, for example, the driver presses and holds both the left and right paddle shifters simultaneously again when, for example, the driver presses and holds both the left and right paddle shifters simultaneously again.

[0034] When control flag 31 is "1", it means that the control flag 31 is in, for example, torque fluctuation control mode. When control flag 31 is "0", it means that the control flag 31 is in, for example, normal mode without periodic torque fluctuation control. Note that the values ​​that control flag 31 can take are not limited to those above.

[0035] The motor 50 is configured to drive the steering wheels of the vehicle 1. The motor 50 is capable of driving the steering wheels of the vehicle 1 according to a target torque Tg input from the motor torque control unit 24. In this specification, the steering wheels refer to at least one of the front wheels and rear wheels. One motor 50 may be provided for the front wheels and another for the rear wheels. In this case, the driving control unit 21 may be capable of controlling the motor 50 for the front wheels and the motor 50 for the rear wheels in common. Alternatively, the driving control unit 21 may be capable of controlling the motor 50 for the front wheels and the motor 50 for the rear wheels independently of each other.

[0036] [Operation] Next, the operation of the travel control unit 21 will be explained with reference to Figure 4. Figure 4 is a diagram illustrating an example of the procedure for deriving the fluctuating torque Tf. Figure 5 is a diagram illustrating an example of the procedure for setting the gain G of the fluctuating torque Tf derived in the procedure of Figure 4, and an example of the procedure for deriving the target torque Tg.

[0037] The driving control unit 21 obtains acceleration requests from the accelerator pedal operation amount sensor 11 and the gear position sensor 12 (step S101). The driving control unit 21 obtains accelerator pedal operation amount data Da from the accelerator pedal operation amount sensor 11 and gear position data Dg from the gear position sensor 12. Next, the driving control unit 21 derives a requested torque Tr corresponding to the obtained acceleration requests (accelerator pedal operation amount data Da and gear position data Dg) (step S102). For example, when the accelerator pedal operation amount data Da is zero, the driving control unit 21 derives the regenerative torque as the requested torque Tr. For example, when the accelerator pedal operation amount data Da is greater than zero, the driving control unit 21 derives the power torque as the requested torque Tr.

[0038] Next, the driving control unit 21 determines whether the vehicle 1 is in a transient state or not when the control flag 31 input from the control flag input unit 40 indicates the torque fluctuation control mode (step S103; Y) (step S104). If the vehicle 1 is in a transient state as a result (step S104; Y), the driving control unit 21 derives a periodically fluctuating torque Tf (step S105). On the other hand, if the control flag 31 input from the control flag input unit 40 indicates the normal mode (step S103; N), or if the vehicle 1 is not in a transient state, that is, if the vehicle 1 is in a steady state (step S104; N), the driving control unit 21 sets the requested torque Tr to the target torque Tg (step S110).

[0039] Next, if the driving control unit 21 has derived the fluctuating torque Tf in step S105, it determines whether the required torque Tr in the transient state is a regenerative torque or not (step S106). If the required torque Tr in the transient state is a regenerative torque (step S106; Y), the driving control unit 21 sets a gain G (e.g., G1, G2, G3, or G4) according to the gear stage (step S107). On the other hand, if the required torque Tr in the transient state is not a regenerative torque, that is, if the required torque Tr in the transient state is a power torque (step S106; N), the driving control unit 21 sets a gain G (e.g., G5, G6, G7, or G8) according to the gear stage (step S108).

[0040] If the drive control unit 21 sets a gain G in step S107 or step S108, it multiplies the fluctuating torque Tf by the gain G to derive a new fluctuating torque (Tf × G) (step S109). Next, the drive control unit 21 derives the target torque Tg by adding the fluctuating torque (Tf × G) to the required torque Tr (step S110). In this way, the target torque Tg is derived.

[0041] Subsequently, the drive control unit 21 derives a target torque Tg by adding a variable torque (Tf × Ga, or Tf × Gb) to the requested torque Tr, and controls the torque of the motor 50 based on the derived target torque Tg. In this way, the torque of the motor 50 is controlled.

[0042] Next, the operation of the travel control unit 21 will be explained with reference to Figures 6 and 7.

[0043] Figure 6 shows an example of how vehicle 1 passes through a corner. Figure 7(A) shows an example of the waveform of the target torque Tg when vehicle 1 passes through a corner. Figure 7(B) shows an example of the time change of accelerator operation amount data Da when vehicle 1 passes through a corner. Figure 7(C) shows an example of the time change of gear stage data Dg when vehicle 1 passes through a corner. Figure 7(D) shows an example of the time change of the on / off state of the torque fluctuation control activation switch when vehicle 1 passes through a corner. The on / off state of the torque fluctuation control activation switch corresponds to "1" and "0" of the control flag 31 described above. Figure 7(E) shows an example of the time change of the state of vehicle 1 when vehicle 1 passes through a corner. Figure 7(E) illustrates how the state of vehicle 1 can be either the steady state or the transient state described above.

[0044] First, vehicle 1 is in a steady state with the gear in 4th gear (D4) and the driver's foot off the accelerator pedal, and the torque fluctuation control activation switch is off. At this time, the driver inputs a control flag 31, which indicates the torque fluctuation control mode, via the control flag input unit 40 at time ta. In this state, when vehicle 1 enters a corner at time tb, the driving control unit 21 detects that vehicle 1 has changed to a transient state. As a result, the driving control unit 21 applies a gain G4 to the fluctuating torque Tf and begins to control the regenerative torque of motor 50 based on the target torque Tg (=Tr+Tf×G4) whose amplitude fluctuates.

[0045] Subsequently, while vehicle 1 is turning a corner, the gear position is changed to 3rd gear (D3) at time tc, 2nd gear (D2) at time td, 3rd gear (D3) at time tf, and 4th gear (D4) at time tg, either by the driver's operation of the shift lever or paddle shifters, or by automatic control by the driving control unit 21. Furthermore, the driver presses the accelerator pedal at time te when vehicle 1 enters the latter half (exit) of the corner. When the driver's foot is released from the accelerator pedal, the driving control unit 21 changes the target torque Tg to regenerative torque (Tr+Tf×G3) at time tc and to regenerative torque (Tr+Tf×G2) at time td. Furthermore, when the driver presses the accelerator pedal, the driving control unit 21 changes the target torque Tg to the powering torque (Tr+Tf×G6) at time te, to the powering torque (Tr+Tf×G7) at time tf, and to the powering torque (Tr+Tf×G8) at time tg. As a result, when the vehicle 1 is entering a corner in the first half (entry), the amplitude of the periodic oscillation of the target torque Tg increases as the gear ratio decreases, for example, as shown in Figure 7. Also, when the vehicle 1 is exiting a corner in the second half (exit), the amplitude of the periodic oscillation of the target torque Tg decreases as the gear ratio increases, for example, as shown in Figure 7.

[0046] [effect] Next, the effects of the control unit 20 according to one embodiment of the present disclosure will be described.

[0047] In this embodiment, in a motor-driven vehicle 1, a target torque Tg is derived by adding a periodically fluctuating torque Tf to a required torque Tr corresponding to an acceleration request, and the torque of the motor 50 is controlled based on the derived target torque Tg. When the vehicle 1 is in a transient state, the gain G of the fluctuating torque Tf changes according to the gear position. As a result, the driver can more easily grasp the grip state between the tires and the road surface, for example, when turning (e.g., when cornering, when turning right or left at an intersection, when changing lanes), and can feel a sense of security and responsiveness to steering. Thus, in this embodiment, by improving driver information, the driver can feel a sense of security and responsiveness to steering. In addition, the driver can feel a driving feeling similar to that of an engine-powered vehicle due to the moderate vibration.

[0048] In this embodiment, the vehicle 1 is determined to be in a steady state or a transient state based on acceleration data and angular velocity data obtained by the vehicle state sensor 13. Furthermore, the gain G of the fluctuating torque Tf is set based on the gear stage data Dg obtained by the gear stage sensor 12. This makes it easier for the driver to grasp the grip state between the tires and the road surface, for example, when turning (e.g., when cornering, when turning right or left at an intersection, when changing lanes), and allows them to feel a sense of security and responsiveness to steering. Thus, in this embodiment, by improving driver information, the driver can feel a sense of security and responsiveness to steering. In addition, the appropriate vibration allows the driver to feel a driving sensation similar to that of an engine-powered vehicle.

[0049] In this embodiment, the gain G5 of the fluctuating torque Tf when the required torque Tr in the transient state is the powering torque and the gear is in 1st gear is smaller than the gain G1 of the fluctuating torque Tf when the required torque Tr in the transient state is the regenerative torque and the gear is in 1st gear. The gain G6 of the fluctuating torque Tf when the required torque Tr in the transient state is the powering torque and the gear is in 2nd gear is smaller than the gain G2 of the fluctuating torque Tf when the required torque Tr in the transient state is the regenerative torque and the gear is in 2nd gear. The gain G7 of the fluctuating torque Tf when the required torque Tr in the transient state is the powering torque and the gear is in 3rd gear is smaller than the gain G3 of the fluctuating torque Tf when the required torque Tr in the transient state is the regenerative torque and the gear is in 3rd gear. When the required torque Tr in the transient state is the power torque and the gear is in 4th gear, the gain G8 of the fluctuating torque Tf is smaller than the gain G4 of the fluctuating torque Tf when the required torque Tr in the transient state is the regenerative torque and the gear is in 4th gear. As a result, during the latter half (start-up) of turns (for example, when cornering, turning right or left at an intersection, or changing lanes), the driver can feel a sense of security and responsiveness to steering while achieving smooth acceleration.

[0050] In this embodiment, based on a control flag 31 input via a control flag input unit 40 provided in the vehicle 1, it is determined whether or not to add the fluctuating torque Tf to the requested torque Tr. When the control flag 31 indicates a torque fluctuation control mode, the target torque Tg is derived by adding the fluctuating torque Tf to the requested torque Tr. This makes it possible to obtain a driving feel that meets the driver's requirements.

[0051] <2. Variant> Although the present disclosure has been described above with reference to embodiments, the present disclosure is not limited to these embodiments, and various modifications are possible.

[0052] In the above embodiment, one motor 50 may be provided for the front wheel, and another may be provided for the rear wheel. In this case, the driving control unit 21 may be capable of independently controlling the motor 50 for the front wheel and the motor 50 for the rear wheel. Furthermore, the motor torque control unit 24 may be capable of separately controlling the torque for the front wheel and the torque for the rear wheel.

[0053] In this configuration, the motor torque control unit 24 can appropriately adjust the driving feel obtained from the front wheels and the driving feel obtained from the rear wheels by separately changing the gain G of the fluctuating torque Tf for the front wheels and the rear wheels. As a result, the driver can feel a greater sense of security and steering response.

[0054] The effects described herein are illustrative only, and the effects of this disclosure are not limited to those described herein. Therefore, other effects may be obtained with respect to this disclosure.

[0055] Furthermore, this disclosure may take the following forms: (1) A vehicle control device capable of controlling a vehicle that is driven by a motor, The system includes a control unit capable of deriving a target torque by adding a periodically fluctuating torque to a required torque corresponding to an acceleration request, and then controlling the motor's torque based on the derived target torque. The control unit is capable of changing the gain of the fluctuating torque according to the gear stage when the vehicle is in a transient state different from a steady state in which the acceleration and angular velocity are below predetermined values. Vehicle control system. (2) The control unit can determine whether the vehicle is in a steady state or a transient state based on acceleration data and angular velocity data obtained by the first sensor, and can also set the gain of the fluctuating torque based on gear stage data obtained by the second sensor. (1) The vehicle control device described above. (3) The control unit can set the gain of the fluctuating torque in the first gear stage to a first gain when the requested torque in the transient state is regenerative torque, and can set the gain of the fluctuating torque in the first gear stage to a second gain that is smaller than the first gain when the requested torque in the transient state is power torque. The vehicle control device described in (1) or (2). (4) The control unit determines whether or not the fluctuating torque should be added to the required torque based on a control flag input via an input unit provided in the vehicle. When the control flag indicates that the fluctuating torque should be added to the required torque, the control unit can derive the target torque by adding the fluctuating torque to the required torque. A vehicle control device as described in any one of (1) to (3). (5) A vehicle control device capable of controlling a vehicle that is driven by a motor, The system derives a target torque by adding a periodically fluctuating torque to the required torque corresponding to the acceleration request, and then controls the motor's torque based on the derived target torque. When the vehicle is in a transient state different from a steady state in which the acceleration and angular velocity are below predetermined values, the gain of the fluctuating torque is changed according to the gear stage. including Vehicle control method.

[0056] The control unit 20 shown in Figure 1 can be implemented by a circuit including at least one semiconductor integrated circuit, such as at least one processor (e.g., a central processing unit (CPU)), at least one application-specific integrated circuit (ASIC) and / or at least one field-programmable gate array (FPGA). The at least one processor can be configured to perform all or some of the functions of the control unit 20 shown in Figure 1 by reading instructions from at least one non-transient, tangible computer-readable medium. Such a medium can take various forms, including, but is not limited to, magnetic media such as hard disks, optical media such as CDs or DVDs, and semiconductor memories (i.e., semiconductor circuits) such as volatile or non-volatile memory. Volatile memory may include DRAM and SRAM. Non-volatile memory may include ROM and NVRAM. An ASIC is an integrated circuit (IC) specialized to perform all or some of the functions of the control unit 20 shown in Figure 1. An FPGA is an integrated circuit designed to be configurable after manufacturing to perform all or some of the functions of the control unit 20 shown in Figure 1.

Claims

1. A vehicle control device capable of controlling a vehicle that is driven by a motor, The system includes a control unit capable of deriving a target torque by adding a periodically fluctuating torque to a required torque corresponding to an acceleration request, and then controlling the motor's torque based on the derived target torque. The control unit is capable of changing the gain of the fluctuating torque according to the gear stage when the vehicle is in a transient state different from a steady state in which the acceleration and angular velocity of the vehicle are below a predetermined value, and when the vehicle is turning. Vehicle control device.

2. A vehicle control device capable of controlling a vehicle that is driven by a motor, The system includes a control unit capable of deriving a target torque by adding a periodically fluctuating torque to a required torque corresponding to an acceleration request, and then controlling the motor's torque based on the derived target torque. The control unit is capable of changing the gain of the fluctuating torque according to the gear stage when the vehicle is in a transient state different from a steady state in which the acceleration and angular velocity are below a predetermined value. The control unit is capable of setting the gain of the fluctuating torque in the first gear stage to a first gain when the requested torque in the transient state is regenerative torque, and setting the gain of the fluctuating torque in the first gear stage to a second gain smaller than the first gain when the requested torque in the transient state is power torque. Vehicle control device.

3. The control unit can determine whether the vehicle is in a steady state or a transient state based on acceleration data and angular velocity data obtained by the first sensor, and can also set the gain of the fluctuating torque based on gear stage data obtained by the second sensor. The vehicle control device according to claim 1 or claim 2.

4. The control unit is capable of setting the gain of the fluctuating torque in the first gear stage to a first gain when the requested torque in the transient state is regenerative torque, and setting the gain of the fluctuating torque in the first gear stage to a second gain smaller than the first gain when the requested torque in the transient state is power torque. The vehicle control device according to claim 1.

5. The control unit determines whether or not the fluctuating torque should be added to the required torque based on a control flag input via an input unit provided in the vehicle. When the control flag indicates that the fluctuating torque should be added to the required torque, the control unit can derive the target torque by adding the fluctuating torque to the required torque. The vehicle control device according to claim 1 or claim 2.

6. A vehicle control method capable of controlling a vehicle that is driven by a motor, The system derives a target torque by adding a periodically fluctuating torque to the required torque corresponding to the acceleration request, and then controls the motor's torque based on the derived target torque. In a transient state different from a steady state in which the acceleration and angular velocity of the vehicle are below a predetermined value, and when the vehicle is turning, the gain of the fluctuating torque is changed according to the gear stage. including Vehicle control method.

7. A vehicle control method capable of controlling a vehicle that is driven by a motor, The system derives a target torque by adding a periodically fluctuating torque to the required torque corresponding to the acceleration request, and then controls the motor's torque based on the derived target torque. When the vehicle is in a transient state different from a steady state in which the acceleration and angular velocity are below predetermined values, the gain of the fluctuating torque is changed according to the gear stage. If the requested torque in the transient state is regenerative torque, the gain of the fluctuating torque in the first gear stage is set to the first gain; if the requested torque in the transient state is power torque, the gain of the fluctuating torque in the first gear stage is set to a second gain smaller than the first gain. including Vehicle control method.

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