Straddle type vehicle and vehicle control method

Abstract

The invention discloses a straddle type vehicle and a vehicle control method. The straddle-type vehicle includes: a vehicle body; an electric motor mounted on the vehicle body as a driving source and rotatable in forward and reverse directions; a battery mounted on the vehicle body and configured to supply electric power to the electric motor; and processing circuitry configured to control the electric motor. The processing circuit is configured to: acquire vehicle state information capable of determining whether a vehicle state of the straddle-type vehicle is a forward driving state or a backward driving state, and operation information capable of determining whether a user operation is a forward driving operation or a backward driving operation; and switching between power operation control and regeneration control based on the vehicle state information and the operation information.

Description

Technical Field

[0001] The present disclosure relates to a straddle-type vehicle and a vehicle control method. Background Art

[0002] JP2010-120597A discloses a vehicle capable of traveling forward and backward.

[0003] In response to a user's operation of a vehicle capable of traveling forward and backward as described above, there is a demand for the user to approach an expected feeling. Summary of the invention

[0004] One aspect of the present disclosure provides a straddle-type vehicle and a vehicle control method.

[0005] According to the present disclosure, a straddle-type vehicle and a vehicle control method can achieve a feeling that a user feels when performing a running operation of the vehicle that is easily close to a feeling that the user expects.

[0006] According to an illustrative aspect of the present disclosure, a straddle-type vehicle includes: a vehicle body; an electric motor mounted on the vehicle body as a drive source and rotatable in a forward direction and a reverse direction; a battery mounted on the vehicle body and configured to supply electric power to the electric motor; and a processing circuit configured to control the electric motor. The processing circuit is configured to: acquire vehicle state information capable of determining whether a vehicle state of the straddle-type vehicle is a forward driving state or a backward driving state, and operation information capable of determining whether a user operation is a forward driving operation or a backward driving operation; and switch between power running control and regeneration control based on the vehicle state information and the operation information.

[0007] According to another illustrative aspect of the present disclosure, a straddle-type vehicle includes: a vehicle body; an electric motor mounted on the vehicle body as a drive source; a battery mounted on the vehicle body and configured to supply electric power to the electric motor; and a processing circuit configured to control the electric motor. The processing circuit is configured to: determine whether the vehicle state is a low-speed driving state in which the regeneration amount is equal to or less than a predetermined value based on vehicle state information during regeneration control; limit a required regeneration torque, which is a regeneration torque required by the electric motor, when the processing circuit determines that the vehicle state is not a low-speed driving state; and reduce the limitation on the required regeneration torque when the processing circuit determines that the vehicle state is a low-speed driving state compared to when the processing circuit determines that the vehicle state is not a low-speed driving state.

[0008] According to another illustrative aspect of the present disclosure, a straddle-type vehicle includes: a vehicle body; an electric motor mounted on the vehicle body as a drive source; a battery mounted on the vehicle body and configured to supply electric power to the electric motor; an operator configured to: receive a first movement operation performed by a user and move in a first direction relative to a reference position, and receive a second movement operation performed by the user and move in a second direction relative to the reference position; and a processing circuit configured to control the electric motor. The processing circuit is configured to: perform power operation control when the vehicle state is a driving state and the user operation is a first movement operation; perform first regeneration control when the vehicle state is a driving state and the user operation is a reference position operation; and perform second regeneration control when the vehicle state is a driving state and the user operation is a second movement operation. The amount of regeneration performed by the second regeneration control is greater than the amount of regeneration performed by the first regeneration control.

[0009] According to another illustrative aspect of the present disclosure, a method for controlling a vehicle including an electric motor rotatable in a forward direction and a reverse direction and a processing circuit, the method being performed in the processing circuit, includes: acquiring vehicle state information capable of determining whether a vehicle state of the vehicle is a forward driving state or a reverse driving state and operation information capable of determining whether a user operation is a forward driving operation or a reverse driving operation; and switching between power running control and regeneration control based on the vehicle state information and the operation information.

[0010] According to the present disclosure, when performing a driving operation of a vehicle, the feeling felt by the user can be made close to the feeling expected by the user. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a schematic diagram of a vehicle according to an embodiment.

[0012] Figure 2 yes Figure 1 An enlarged view of the area around the steering wheel and instrument panel of a vehicle.

[0013] Figure 3 It is shown Figure 1 A block diagram of the electrical configuration of a vehicle.

[0014] Figure 4 is a table showing the correspondence between the vehicle state, user operation, control form, and setting value during low-speed control.

[0015] Figure 5 : is a flowchart showing the flow of the torque command output process.

[0016] Figure 6 is a graph showing an example of a temporal change in the motor rotation speed in the low speed mode.

[0017] Figure 7 yes Figure 3 Block diagram of the low speed control unit in .

[0018] Figure 8 It is shown by Figure 7 A graph showing the removal of noise from the actual rotational speed performed by the rate of change limiting unit and the filter processing unit in FIG.

[0019] Fig. 9 It is shown by Figure 7 A graph showing the deviation limiting process performed by the deviation limiting unit in FIG.

[0020] Fig.10 is an example of an offset torque graph.

[0021] Fig.11 yes Figure 3 Block diagram of the torque limiting unit in . DETAILED DESCRIPTION

[0022] Hereinafter, embodiments will be described with reference to the accompanying drawings.

[0023] (Vehicle Configuration)

[0024] Figure 1 is a schematic diagram of a vehicle 1 according to an embodiment. In the present embodiment, the vehicle 1 is a straddle-type electric motorcycle. The vehicle 1 includes a vehicle body 2 and a battery pack 3. The battery pack 3 is detachable from the vehicle body 2. However, the battery pack 3 may not be detachable from the vehicle body 2. The vehicle body 2 is supported by a front wheel 4 as a driven wheel and a rear wheel 5 as a driving wheel. An electric motor 6 as a driving source for traveling is supported by the vehicle body 2.

[0025] The electric motor 6 generates a driving force for traveling to be transmitted to the rear wheels 5 as driving wheels. The driving torque generated by the electric motor 6 is transmitted to the rear wheels 5 via the power transmission mechanism 7. The electric motor 6 is rotatable forward and backward. The electric motor 6 not only functions as a driving source for traveling, but also functions as a generator during deceleration of the vehicle 1. The electric motor 6 is provided with a rotation speed sensor 22 (see FIG. 2 ) for detecting the rotation speed of the output shaft of the electric motor 6. Figure 3 The power transmission mechanism 7 includes a speed reducer 7a for reducing the rotation of the electric motor 6, and a mechanism 7b (for example, a chain transmission mechanism or a belt transmission mechanism) for transmitting the rotation power output from the speed reducer 7a to the axle of the rear wheel 5.

[0026] The vehicle body 2 includes a vehicle body frame, and the vehicle body frame includes a head pipe 11 and a pair of left and right main frames 12 extending rearward from the head pipe 11. The head pipe 11 rotatably supports a steering shaft 13. A front fork 14 extending generally in the up-down direction is connected to the steering shaft 13, and the front wheel 4 is rotatably supported at the lower end portion of the front fork 14. A battery box 17 is provided between the pair of main frames 12 extending in the left-right direction. The battery box 17 is fixed to the pair of main frames 12. The battery pack 3 is accommodated in the battery box 17. A rod-type steering wheel 15 extending in the left-right direction is connected to the upper end portion of the steering shaft 13. An instrument device 18 supported by the head pipe 11 via a bracket 16 is provided on the front side of the steering wheel 15.

[0027] Figure 2 yes Figure 1 FIG. 1 is an enlarged view of the vicinity of the steering wheel 15 and the instrument device 18 of the vehicle 1 in FIG. The steering wheel 15 is provided with a torque command operator 15a that receives an operation of generating a driving torque by the electric motor 6. In the present embodiment, the torque command operator 15a is a right grip of the steering wheel 15. The torque command operator 15a is pivotable about a central axis C extending in the longitudinal direction within a predetermined angle range.

[0028] The torque command operator 15a is configured to return to a predetermined reference position when not operated by a user (i.e., a driver). The torque command operator 15a can pivot about the center axis C from the predetermined reference position in a first moving direction R1 and pivot about the center axis C in a second moving direction R2 opposite to the first moving direction R1. The torque command operator 15a is pushed to the reference position when not operated. When the torque command operator 15a pivots from the reference position in the first moving direction R1 or the second moving direction R2, the moving direction of the torque command operator 15a and the operation amount from the reference position (hereinafter referred to as the accelerator operation amount) are detected by the accelerator sensor (see Figure 3 ).

[0029] A brake lever 19 is provided in front of the right grip of the torque command operator 15a. The brake lever 19 is a torque command operator for operating a front wheel brake mechanism provided on the front wheel 4. When the brake lever 19 is pulled forward, the front wheel brake mechanism is operated to apply a mechanical braking force to the front wheel 4.

[0030] The mode switching switch 23 is provided on a side opposite to the side where the torque command operator 15a of the steering wheel 15 is positioned in the left-right direction, that is, on a left side portion of the steering wheel 15. The mode switching switch 23 receives a user operation for switching a control mode of a controller 31 to be described later between a normal travel mode and a low speed mode.

[0031] The normal driving mode is a mode in which the torque of the electric motor 6 is changed according to the operation amount of the torque command operator 15a by the user. Specifically, in the normal driving mode, the controller 31 increases the output as the operation amount of the torque command operator 15a in the first moving direction increases. When the torque command operator 15a pivots from the reference position along the first moving direction R1 in the normal driving mode, the electric motor 6 generates a driving torque according to the operation amount of the torque command operator 15a pivoting from the reference position along the first moving direction. The normal driving mode is set as a mode for driving on a driving road. For example, in the normal driving mode, when a minimum driving speed is set in the driving road, the vehicle can travel at a speed exceeding the minimum driving speed.

[0032] The low speed mode is a mode in which the maximum driving speed is limited compared to the normal driving mode and the vehicle 1 travels in a low speed driving state. That is, in the low speed mode, the maximum driving speed is set to be lower than the maximum driving speed in the normal driving mode. For example, when the vehicle 1 includes a speed limiter that limits the maximum speed of the electric motor 6, the maximum driving speed in the normal driving mode is the driving speed when the vehicle 1 rotates at the maximum speed limited by the speed limiter in the normal driving mode, and the maximum driving speed in the low speed mode is set to be lower than the driving speed. The low speed mode can be used, for example, when the vehicle 1 is parked from the driving road to the parking lot or moved from the parking lot to the driving road. In addition, the low speed mode can be used for a change of direction using a backward turn, a movement from a stopped state on a slope to a starting position, or the like. In the low speed mode, the speed can be set to about walking speed as the maximum driving speed.

[0033] In the low speed mode, the vehicle 1 can travel forward or backward in a low speed driving state according to the operation on the torque command operator 15a. For example, when the torque command operator 15a is pivoted by a first angle or more in the first moving direction R1 from the reference position in the low speed mode, the vehicle 1 travels forward slowly with the maximum forward driving speed set in the low speed mode as the upper limit. When the torque command operator 15a is pivoted by a second angle or more in the second moving direction R2 from the reference position in the low speed mode, the vehicle 1 travels backward slowly with the maximum backward driving speed set in the low speed mode as the upper limit.

[0034] like Figure 2 As shown, the meter device 18 displays in a distinguishable manner whether the control mode of the controller 31 is the normal driving mode or the low speed mode. For example, when the selected control mode is the low speed mode, the meter device 18 may display a set of information related to the absolute value of the driving speed and information related to whether the driving direction of the vehicle 1 is the forward driving direction or the reverse driving direction. In addition, the meter device 18 may display various information such as the motor speed and the remaining amount of the battery.

[0035] (Electrical Configuration)

[0036] Figure 3 It is shown Figure 1 31 is a block diagram of an electrical configuration of a vehicle 1 in FIG. A controller 31 and an inverter 32 are fixed to a vehicle body 2 of the vehicle 1. The controller 31 includes a processor, a memory, and an I / O interface in terms of hardware. The memory includes, for example, a storage device such as a hard disk or a flash memory, and a main memory which is a RAM. The storage device stores a program for issuing a control command to the electric motor 6. The processor, memory, and the like included in the controller 31 are examples of a processing circuit.

[0037] The controller 31 receives accelerator operation amount information indicating the accelerator operation amount detected by the accelerator sensor 21. The accelerator operation amount information detected by the accelerator sensor 21 includes information on the movement direction and movement amount of the torque command operator 15a from the reference position by the user operation.

[0038] The controller 31 receives motor speed information indicating the motor speed detected by the speed sensor 22 .

[0039] The controller 31 receives a mode switching signal from the mode switching switch 23 for switching the control mode from the normal driving mode to the low-speed mode or from the low-speed mode to the normal driving mode. The controller 31 switches the control mode between the normal driving mode and the low-speed mode based on the received mode switching signal. The mode switching switch 23 can transmit the mode switching signal to the controller 31 by being long pressed, or can transmit the mode switching signal to the controller 31 by being short pressed. In the present embodiment, when the user continuously presses the mode switching switch 23 for a predetermined time in the driving stop state of the vehicle 1, the mode switching signal can be transmitted from the mode switching switch 23 to the controller 31. In this case, when the current control mode is the normal driving mode, the controller 31 switches to the low-speed mode. When the current control mode is the low-speed mode, the controller 31 switches to the normal driving mode.

[0040] When the controller 31 receives a mode switching signal related to switching from the normal driving mode to the low speed mode, the controller 31 may determine whether a predetermined mode switching condition for switching from the normal driving mode to the low speed mode is satisfied, and switch from the normal driving mode to the low speed mode in response to determining that the mode switching condition is satisfied. For example, the mode switching condition may include a condition that the vehicle speed is equal to or lower than a predetermined speed. For example, the mode switching condition may include a condition that the motor speed is equal to or lower than a predetermined speed. When the vehicle 1 includes a transmission device that changes the transmission ratio, for example, the mode switching condition may include a condition that the transmission ratio of the transmission device is a predetermined transmission ratio.

[0041] The controller 31 also communicates with electronic devices built into the battery pack 3. The battery pack 3 includes a battery 3a, a temperature sensor 3b, and a battery management unit (BMU) 3c. The battery 3a includes a plurality of battery cells connected in series. The temperature sensor 3b detects the temperature of the battery 3a.

[0042] The battery management unit 3c includes a processor, a memory, an I / O interface, and the like in terms of hardware. The memory includes, for example, a storage device such as a hard disk or a flash memory, and a main memory which is a RAM. The memory of the battery management unit 3c stores battery identification information for identifying the battery pack 3, and restriction information related to the limit value of the discharge current of the battery 3a and the limit value of the charge current of the battery 3a.

[0043] The battery management unit 3c estimates the amount of electricity stored in the battery 3a, that is, the state of charge (SOC) of the battery 3a. For example, the battery pack 3 may include a voltage sensor that detects a voltage value of each battery cell of the battery 3a and a current sensor that detects a charging current to the battery 3a and a discharging current from the battery 3a, and the battery management unit 3c may estimate the state of charge of the battery 3a based on the voltage value of each battery cell detected by the voltage sensor, the amount of current to be charged or discharged detected by the current sensor, and the like.

[0044] The controller 31 receives from the battery pack 3 battery temperature information indicating the temperature of the battery 3 a detected by the temperature sensor 3 b and charge state information (hereinafter also referred to as SOC information) indicating the charge state of the battery 3 a estimated by the battery management unit 3 c .

[0045] The controller 31 and the inverter 32 are communicably connected to each other. The battery 3a is electrically connected to the electric motor 6 via the inverter 32. The controller 31 sends a control command to the inverter 32 to control the inverter 32. Under the control of the controller 31, the inverter 32 converts the DC power discharged from the battery 3a into AC power and supplies the AC power to the electric motor 6, or converts the AC power generated by the electric motor 6 into DC power using the power transmitted from the rear wheel 5 as the driving wheel and supplies the DC power to the battery 3a to charge the battery 3a.

[0046] The controller 31 functionally includes a normal travel control unit 41, a low speed control unit 42, a torque limit unit 43, and the like. The normal travel control unit 41, the low speed control unit 42, and the torque limit unit 43 are implemented by a processor that performs arithmetic processing on a program read from a storage device to a main memory.

[0047] The normal driving control unit 41 controls the electric motor 6 when the control mode of the controller 31 is the normal driving mode. More specifically, the memory of the controller 31 stores correspondence information indicating the correspondence between the accelerator operation amount, the motor speed and the torque. The correspondence information may be, for example, a torque map or an arithmetic expression. The correspondence information may be information indicating at least the correspondence between the accelerator operation amount and the torque. When the control mode of the controller 31 is the normal driving mode, the normal driving control unit 41 refers to the correspondence information, obtains the torque corresponding to the accelerator operation amount indicated by the received accelerator operation amount information and the motor speed indicated by the received motor speed information, and determines the torque as the required torque Tr required by the electric motor 6.

[0048] The low speed control unit 42 controls the electric motor 6 when the control mode of the controller 31 is the low speed mode. The low speed control unit 42 includes a vehicle state information acquisition unit 42a, an operation information acquisition unit 42b, a low speed rotation speed control unit 42c, and a low speed torque control unit 42d.

[0049] The vehicle state information acquisition unit 42a acquires vehicle state information indicating the state of the vehicle 1. The vehicle state information is information capable of determining whether the vehicle state is a forward driving state or a backward driving state. The vehicle state information acquisition unit 42a acquires the vehicle state information by determining the vehicle state from the motor rotation speed information.

[0050] In the present embodiment, when the motor speed information indicates that the electric motor 6 rotates in the positive direction, the vehicle state information acquisition unit 42a determines that the vehicle state is the forward driving state. When the motor speed information indicates that the electric motor 6 rotates in the negative direction, the vehicle state information acquisition unit 42a determines that the vehicle state is the backward driving state. In the present specification, the positive direction of the electric motor 6 is the rotation direction of the electric motor 6 that generates the driving torque for accelerating the vehicle 1 forward, and the negative direction of the electric motor 6 is the rotation direction of the electric motor 6 that generates the driving torque for accelerating the vehicle 1 backward. When the motor speed information indicates that the motor speed is zero, the vehicle state information acquisition unit 42a determines that the vehicle state is the stopped state.

[0051] The operation information acquisition unit 42b acquires operation information indicating the operation content of the torque command operator 15a by the user in the low speed mode. The operation information is information capable of determining whether the user operation in the low speed mode is a forward travel operation or a reverse travel operation, and the user operation is a reference position operation. The operation information acquisition unit 42b acquires the determination result as the operation information by determining which one of the forward travel operation, the reverse travel operation, and the reference position operation corresponds to the user operation from the accelerator operation amount information.

[0052] In the present embodiment, when the accelerator operation amount information indicates that the position of the torque command operator 15a is at a position where the torque command operator 15a is pivoted by a first angle or more from the reference position in the first moving direction R1, the operation information acquisition unit 42b determines that the user operation is a forward travel operation as the first moving operation. When the accelerator operation amount information indicates that the position of the torque command operator 15a is at a position where the torque command operator 15a is pivoted by a second angle or more from the reference position in the second moving direction R2, the operation information acquisition unit 42b determines that the user operation is a backward travel operation as the second moving operation.

[0053] In the case where it is determined that the user operation is neither the forward driving operation nor the reverse driving operation, the operation information acquisition unit 42b determines that the user operation is the reference position operation. That is, when the accelerator operation amount information indicates that the position of the torque command operator 15a is at a position smaller than the first angle of the first moving direction R1 from the reference position and smaller than the second angle of the second moving direction R2 from the reference position, the operation information acquisition unit 42b determines that the user operation is the reference position operation.

[0054] When the user does not operate the torque command operator 15a, the torque command operator 15a returns to the reference position, and thus the user operation is determined as the reference position operation even when no user operation is performed on the torque command operator 15a.

[0055] The low speed control unit 42c performs speed control in which the actual speed of the electric motor 6 approaches the target speed in the low speed mode. When the speed control condition is met in the low speed mode, the speed control performed by the low speed control unit 42c is selected and executed. For example, the speed control condition is a condition that the vehicle is in a driving state and the user operation is a forward driving operation or a backward driving operation. The low speed control unit 42c controls the speed so that the actual speed approaches the target speed. Specifically, the low speed control unit 42c calculates the torque for making the actual speed close to the target speed based on the deviation between the actual speed and the target speed, and determines the torque as the required torque Tr required for the electric motor 6. The details of the speed control performed by the low speed control unit 42c will be described later.

[0056] The low-speed torque control unit 42d performs a predetermined torque control. When the torque control condition is satisfied in the low-speed mode, the torque control performed by the low-speed torque control unit 42d is selected and executed. As will be described later, when the vehicle is in a running state and the user operation is a reference position operation, the torque control condition is satisfied and the torque control performed by the low-speed torque control unit 42d is selected. The low-speed torque control unit 42d obtains the regenerative torque corresponding to the motor speed indicated by the motor speed information, and determines the regenerative torque as the required torque Tr required by the electric motor 6.

[0057] The torque limiting unit 43 executes a torque limiting process that limits the torque required by the electric motor 6 so as not to exceed the upper limit value of the discharge current and the upper limit value of the charge current of the battery 3a.

[0058] (Control form and setting value in low speed mode)

[0059] Figure 4 42d is a table showing the correspondence between the vehicle state, user operation, control form and setting value in the low speed mode. Whether the speed control by the low speed speed control unit 42c or the torque control by the low speed torque control unit 42d is performed depends on the combination of the vehicle state indicated by the vehicle state information and the user operation indicated by the operation information.

[0060] like Figure 4 As shown, in the case where it is determined that the power running control condition is satisfied, the controller 31 performs the power running control for causing the electric motor 6 to generate a driving torque for causing the vehicle 1 to run. The power running control condition is a condition where the vehicle state is a forward running state and the user operation is a forward running operation, or a condition where the vehicle state is a backward running state and the user operation is a backward running operation. That is, in the case where it is determined from the vehicle state information and the operation information that the vehicle state is a forward running state and the user operation is a forward running operation, or in response to determining that the vehicle state is a backward running state and the user operation is a backward running operation, the controller 31 performs the power running control.

[0061] The power running control in the low speed mode is a control form of speed control performed by the low speed control unit 42c described above, and makes the actual speed of the electric motor 6 close to the target speed. From the moment when it is determined that the power running control condition is satisfied, the target speed in the power running control is gradually increased while satisfying the power running control condition, and is maintained at a predetermined limit speed (limit speed) (see also Figure 6 ). The speed limit during low-speed running is set to a value sufficiently smaller than the speed limit set in the normal running mode. The rate of increase of the target rotation speed or the upper limit speed does not depend on the amount of operation performed by the user on the torque command operator 15a, as long as the torque command operator 15a is in a position exceeding the first angle in the first moving direction R1 from the reference position or the torque command operator 15a is in a position exceeding the second angle in the second moving direction R2 from the reference position. That is, the target rotation speed in the power running control in the low-speed mode is set to change in basically the same manner regardless of whether the amount of operation for the torque command operator 15a is large or small.

[0062] In the case where it is determined that the first regeneration control condition is satisfied, the low-speed control unit 42 performs the first regeneration control for causing the electric motor 6 to generate a regeneration torque, i.e., a torque for braking the vehicle 1. The first regeneration control condition is the above-mentioned torque control condition, and the first regeneration control in the low-speed mode is the torque control of the above-mentioned low-speed torque control unit 42d. That is, the first regeneration control condition is a condition that the vehicle state is a forward driving state and the user operation is a reference position operation, or a condition that the vehicle state is a backward driving state and the user operation is a reference position operation. In the case where it is determined from the vehicle state information and the operation information that the vehicle state is a forward driving state and the user operation is a reference position operation, or in response to determining that the vehicle state is a backward driving state and the user operation is a reference position operation, the controller 31 performs the first regeneration control.

[0063] In the case where it is determined that the second regeneration control condition is satisfied, the low-speed control unit 42 performs the second regeneration control for causing the electric motor 6 to generate a regeneration torque, i.e., a torque for braking the vehicle 1. The second regeneration control condition is a condition where the vehicle state is in a forward driving state and the user operation is a backward driving operation, or a condition where the vehicle state is in a backward driving state and the user operation is a forward driving operation. That is, in the case where it is determined from the vehicle state information and the operation information that the vehicle state is in a forward driving state and the user operation is a backward driving operation, or in response to determining that the vehicle state is in a backward driving state and the user operation is a forward driving operation, the controller 31 performs the second regeneration control. The second regeneration control in the low-speed mode is a control form of the speed control of the above-mentioned low-speed speed control unit 42c.

[0064] The second regenerative control generates a greater regenerative braking force than the first regenerative control. The regenerative amount (i.e., the amount of regenerative power generated) by the second regenerative control is greater than the regenerative amount by the first regenerative control. The regenerative amount obtained by the second regenerative control when the vehicle state is a forward driving state is different from the regenerative amount obtained by the second regenerative control when the vehicle state is a backward driving state. The regenerative amount obtained by the second regenerative control when the vehicle state is a forward driving state is greater than the regenerative amount obtained by the second regenerative control when the vehicle state is a backward driving state.

[0065] Next, we will refer to Figure 5 The flow of the torque command output process for outputting a torque command to the electric motor 6 is described. In the torque command output process, the controller 31 determines whether the current control mode is the low speed mode (step S1).

[0066] In response to determining that the current control mode is the low-speed mode (step S1: yes), the controller 31 determines whether the torque control condition is satisfied, in other words, whether the condition that the vehicle is in a running state and the user operation is a reference position operation is satisfied (step S2). In response to determining that the torque control condition is satisfied (step S2: yes), the controller 31 determines the required torque Tr through low-speed torque control (which is torque control performed by the low-speed torque control unit 42d) (step S3).

[0067] In response to determining that the torque control condition is not satisfied (step S2: NO), the controller 31 determines the required torque Tr through the low speed rotational speed control which is the rotational speed control performed by the low speed rotational speed control unit 42c (step S4).

[0068] In response to determining in step S1 that the current control mode is not the low speed mode (step S1 : NO), the controller 31 determines the required torque Tr through the normal torque control, which is the torque control performed by the normal travel control unit 41 (step S5 ).

[0069] After determining the required torque Tr in any one of steps S3, S4 and S5, the controller 31 performs torque limitation processing to generate a torque command so that the required torque for the electric motor 6 does not exceed a predetermined upper limit value (step S6), and outputs the generated torque command to the inverter 32 (step S7).

[0070] In the case where the predetermined end condition is not satisfied (step S8: No), the controller 31 repeats the steps from step S1 to step S7. In response to determining that the predetermined end condition is satisfied (step S8: Yes), the controller 31 terminates the torque command output process.

[0071] Reference Figure 6 The control form in the low speed mode is described in more detail. Figure 6 1 shows the time changes of the target rotation speed and the actual rotation speed of the electric motor 6 when the user performs a forward driving operation and then performs a reverse driving operation in a case where the control mode is the low speed mode. Figure 6 The graph indicated by the solid line in is the target rotation speed of the electric motor 6, and the graph indicated by the dotted line is the actual rotation speed of the electric motor 6. The horizontal axis indicates the elapsed time t, and the vertical axis indicates the rotation speed.

[0072] When the user starts the forward driving operation in a state where the control mode is the low speed mode and the vehicle 1 is stopped ( Figure 6The controller 31 selects and executes the power operation control, which is a control form of the speed control performed by the low-speed speed control unit 42c. The power operation control in the low-speed mode is a speed control for making the actual speed of the electric motor 6 close to the target speed, specifically, the speed feedback control. In the present embodiment, PID feedback control is used as an example. The controller 31 changes the target speed at a first change rate α as time passes until the target speed reaches a predetermined first limit speed Mf_lim. The first change rate α is the rotational acceleration of the speed of the electric motor 6. The first change rate α includes a first starting change rate α1 and a first running change rate α2. The absolute value of the first starting change rate α1 is greater than the absolute value of the first running change rate α2.

[0073] As time passes, the controller 31 changes the target speed at a first change rate for startup. The controller 31 determines whether a first change rate switching condition is satisfied while changing the target speed at the first startup change rate α1. The first change rate switching condition is a condition where the absolute value of the actual speed of the electric motor 6 exceeds the absolute value of a predetermined threshold value Mf_s. In the case where it is determined that the first change rate switching condition is satisfied ( Figure 6 The controller 31 changes the target speed at the first driving change rate α2 as time passes. When the target speed reaches the first speed limit Mf_lim ( Figure 6 The controller 31 maintains the target speed at the first limit speed Mf_lim (the elapsed time t=t3). For example, the controller 31 increases the required torque Tr as the deviation between the target speed and the actual speed increases. The controller 31 maintains the required torque Tr in a state where the deviation between the target speed and the actual speed is zero.

[0074] In this way, whether to perform the power running control of the low speed mode is selected depending on whether the operation amount for the torque command operator 15a is equal to or greater than a predetermined value. As long as the operation amount for the torque command operator 15a is equal to or greater than a predetermined value, the rate of change of the target speed is set to a constant rate of change α (increase rate), regardless of the magnitude of the operation amount. The first speed limit Mf_lim is set to a value corresponding to the low speed driving speed of the vehicle. The low speed driving speed is set to a value much smaller than the maximum forward driving speed of the vehicle that can occur in the normal driving mode, for example, 10km / h or less. In the present embodiment, the speed of the vehicle corresponding to the first speed limit Mf_lim is about 5km / h in the forward driving direction on a flat driving road.

[0075] In the following, when the user performs the reference position operation to return the torque command operator 15a to the reference position ( Figure 6 , in other words, when the user's operation amount is equal to or less than a predetermined value, more specifically, when the torque command operator 15a pivots from the reference position to a position less than the first angle along the first moving direction R1 and pivots from the reference position to a position less than the second angle along the second moving direction R2, the controller 31 selects and executes the first regenerative control, that is, the torque control performed by the low-speed torque control unit 42d. In this case, in the low-speed mode, the controller 31 performs regenerative torque control with reference to the corresponding relationship information stored in the memory to be described later, which is used to control the electric motor 6 to generate a regenerative torque corresponding to the received motor speed. The vehicle 1 is decelerated by the regenerative braking force caused by the first regenerative control, and the actual speed of the electric motor 6 decreases. Figure 6 During the period between time t4 and time t5 in FIG. 1 , since torque control is performed instead of rotation speed control, the target rotation speed indicated by the solid line is not shown, and only the actual rotation speed indicated by the dotted line is shown.

[0076] In the following, when the user performs a reverse driving operation during deceleration ( Figure 6 The controller 31 selects the speed control performed by the low speed control unit 43c and changes from the first regeneration control to the second regeneration control. In the second regeneration control, the controller 31 sets the target speed to zero and performs feedback control on the electric motor 6 so that the speed of the electric motor 6 is zero. During the period until the actual speed is reduced to zero (from Figure 6 From time t5 to time t6 in the figure, a regenerative braking force greater than that during the first regenerative control acts.

[0077] When the actual speed reaches zero during reverse driving operation ( Figure 6 The selection of the speed control by the low speed control unit 43c is continued, and the second regenerative control is switched to the power running control for causing the electric motor 6 to generate a driving torque in the negative direction. The power running control in the low speed mode is a speed control for making the actual speed of the electric motor 6 close to the target speed. The controller 31 changes the target speed at a second change rate β over time until the target speed reaches a predetermined second limit speed Mr_lim. The second change rate β is the rotational acceleration of the speed of the electric motor 6. The second change rate includes a second starting change rate β1 and a second driving change rate β2. The absolute value of the second starting change rate β1 is greater than the absolute value of the second driving change rate β2.

[0078] As time passes, the controller 31 changes the target speed at the second change rate β1 for startup. The controller 31 determines whether the second change rate switching condition is satisfied while changing the target speed at the second startup change rate β1. The second change rate switching condition is a condition that the absolute value of the actual speed of the motor exceeds the absolute value of the predetermined threshold value Mr_s. In the case of determining that the second change rate switching condition is satisfied ( Figure 6 The controller 31 changes the target speed at the second driving change rate β2 as time passes. When the target speed reaches the second limit speed Mr_lim ( Figure 6 The controller 31 maintains the target speed at the second speed limit Mr_lim, after the elapsed time t=t8 in the vehicle. The second speed limit Mr_lim is set to a value corresponding to the low-speed driving speed of the vehicle. The low-speed driving speed is set to a value much smaller than the maximum forward driving speed of the vehicle that can occur in the normal driving mode, for example, 10 km / h or less. In the present embodiment, the speed of the vehicle corresponding to the second speed limit Mr_lim is about 3 km / h in the backward driving direction on a flat driving road.

[0079] Therefore, even when the vehicle state is the forward driving state or the reverse driving state, the power running control, the first regeneration control, and the second regeneration control can be performed according to the user operation. Figure 4 As shown, in the present embodiment, even in the same control form, the absolute values ​​of the setting values ​​for various controls may differ depending on whether the vehicle state is the forward driving state or the reverse driving state. For example, the absolute values ​​of the setting values ​​of the following parameters (i) to (vii) differ between the speed control performed in the forward driving state and the speed control performed in the reverse driving state.

[0080] (i) Absolute value of the change rate of the target speed (first change rate α, second change rate β)

[0081] (ii) Absolute value of maximum target speed (Mf_lim, Mr_lim)

[0082] (iii) Absolute values ​​of the thresholds (Mf_s, Mr_s) for switching conditions of the rate of change of the target speed

[0083] (iv) Absolute value of deviation limit value (Df, Dr)

[0084] (v) Absolute value of threshold value for high-speed processing switching condition

[0085] (vi) Absolute value of offset torque

[0086] (vii) Absolute values ​​of upper limit torque and lower limit torque

[0087] (i) The absolute value of the rate of change of the target speed (first rate of change α, second rate of change β) will be described. In the power running control when the vehicle 1 is in the forward driving state, the target speed is changed at the first rate of change α as time passes, and in the power running control when the vehicle 1 is in the backward driving state, the target speed is changed at the second rate of change β as time passes. The absolute value of the first rate of change α is greater than the absolute value of the second rate of change β. For example, the absolute value of the first start-up change rate α1 is greater than the absolute value of the second start-up change rate β1. For example, the absolute value of the first driving change rate α2 is greater than the absolute value of the second driving change rate β2.

[0088] (ii) The absolute value of the maximum target speed (Mf_lim, Mr_lim) will be described. In the power running control when the vehicle 1 is in the forward driving state, the maximum target speed is limited to the first limited speed Mf_lim, and in the power running control when the vehicle 1 is in the backward driving state, the maximum target speed is limited to the second limited speed Mr_lim. The absolute value of the first limited speed Mf_lim is greater than the absolute value of the second limited speed Mr_lim. For example, the first limited speed Mf_lim is a speed set so that the vehicle speed is 5km / h in the forward driving direction, and the second limited speed Mr_lim is a speed set so that the vehicle speed is 3km / h in the backward driving direction. That is, in the low speed mode of the present embodiment, the absolute value of the maximum driving speed is greater in the forward driving than in the backward driving. As described above, in the present embodiment, the speed of the vehicle corresponding to the first limited speed Mf_lim is about 5km / h on a flat driving road, and the speed of the vehicle corresponding to the second limited speed Mr_lim is about 3km / h on a flat driving road.

[0089] (iii) The absolute values ​​of the threshold values ​​(Mf_s, Mr_s) that describe the switching conditions of the rate of change of the target speed. In the power running control when the vehicle 1 is in the forward driving state, when the absolute value of the actual speed of the motor exceeds the absolute value of the threshold value Mf_s, the first rate of change of the target speed is switched from the first starting rate of change α1 to the first driving rate of change α2. In the power running control when the vehicle 1 is in the backward driving state, when the absolute value of the actual speed of the motor exceeds the absolute value of the threshold value Mr_s, the second rate of change of the target speed is switched from the second starting rate of change β1 to the second driving rate of change β2. The absolute value of the threshold value Mf_s when driving forward is greater than the absolute value of the threshold value Mr_s when driving backward.

[0090] The details of parameters (iv), (v), (vi) and (vii) will be described later.

[0091] (Low speed control)

[0092] Reference Figures 7 to 10The rotation speed control process performed by the low speed rotation speed control unit 42c is described below. Figure 7 As shown, the low speed rotation control unit 42c includes a change rate limiting unit 51, a filter processing unit 52, a data acquisition unit 53, a deviation limiting unit 54, a deviation acquisition unit 55, a PID control unit 56, an offset torque acquisition unit 57 and an addition unit 58.

[0093] The rate-of-change limiting unit 51 and the filter processing unit 52 remove noise from the motor rotation speed detected by the rotation speed sensor 22. Specifically, the rate-of-change limiting unit 51 performs a rate-of-change limiting filter process on the motor rotation speed detected by the rotation speed sensor 22. The rate-of-change limiting filter process is a process for limiting the time rate of change within a predetermined range with respect to the time series data of the actual rotation speed of the electric motor 6. The filter processing unit 52 performs a low-pass filter process (high-frequency component removal process) on the data subjected to the rate-of-change limiting filter process performed by the rate-of-change limiting unit 51.

[0094] Figure 8 It is shown by Figure 7 A graph showing the removal of noise from the actual rotation speed performed by the change rate limiting unit 51 and the filtering processing unit 52. Figure 8 The graph indicated by the solid line in FIG. 2 shows the raw data of the rotation speed sensor 22, and shows the time change of the actual rotation speed of the electric motor 6 detected by the rotation speed sensor 22. In this example, the actual rotation speed gradually increases, and is then maintained at a certain rotation speed. The actual rotation speed changes sharply at a certain moment. This sharp change in the actual rotation speed causes a sharp change in the required torque Tr as the output of the low speed control unit 42c, and is preferably removed before the PID control is executed.

[0095] Figure 8 The graph indicated by the dotted line in FIG. 1 shows a result obtained by performing a low-pass filter process only on the actual rotation speed data detected by the rotation speed sensor 22. When the graph indicated by the dotted line is compared with the graph indicated by the solid line, the low-pass filter process is performed to smooth the graph indicated by the solid line to obtain data from which noise is removed. However, when the data is processed only by the low-pass filter process, the time delay of the processed data becomes large relative to the sensor data shown in the graph indicated by the solid line.

[0096] Figure 8The graph indicated by a single-point chain line in FIG. 1 shows the result obtained by performing a change rate limiting filter process and a low-pass filter process on the actual rotation speed data detected by the rotation speed sensor 22. The actual rotation speed data detected by the rotation speed sensor 22 is first subjected to a change rate limiting filter process to reduce the amplitude of noise, and is further smoothed by a low-pass filter process. Since the amplitude of noise is reduced, it is possible to prevent the filter process from being excessive compared to the case where processing is performed only by a low-pass filter process. Therefore, it is possible to prevent an increase in the time delay relative to the sensor data.

[0097] Back to Figure 7 , the data acquisition unit 53 acquires the target speed data. The target speed data is data related to how the target speed changes over time. For example, the target speed data is data used to change the target speed to the limit speeds Mf_lim and Mr_lim at preset change rates α, β over time, and to change the target speed when the target speed reaches the limit speeds Mf_lim and Mr_lim so as to keep the target speed at the limit speeds Mf_lim and Mr_lim. The target speed data includes information related to the setting values ​​of the above parameters (i), (ii) and (iii). The memory of the controller 31 stores a plurality of target speed data, and the data acquisition unit 53 selects and acquires a target speed data from the plurality of target speed data based on the vehicle state information and the operation information.

[0098] The deviation limiting unit 54 performs a deviation limiting process for limiting the increase in the absolute value of the target speed according to the actual speed. The deviation limiting process is a process for preventing the deviation δ between the target speed and the actual speed of the electric motor 6 from becoming excessively large. The deviation limiting unit 54 acquires the target speed from the data acquisition unit 53, and acquires the actual speed from which noise is removed by the change rate limiting unit 51 and the filter processing unit 52. The deviation limiting unit 54 limits the change in the target speed so that the deviation obtained by subtracting the acquired actual speed from the acquired target speed does not exceed a predetermined deviation limit value.

[0099] Fig. 9 It is shown by Figure 7 Graph showing the deviation limiting process performed by the deviation limiting unit 54 in FIG. Fig. 9 , the horizontal axis represents time, and the vertical axis represents the rotation speed. Fig. 9 The graph indicated by a solid line in FIG. 1 shows the time variation of the target rotation speed when the deviation limiting process is executed, and the graph indicated by a dotted line shows the time variation of the actual rotation speed when the deviation limiting process is executed. For comparison, Fig. 9 Also shown are the target rotation speed and the actual rotation speed when the deviation limiting process is not executed. Fig. 9The graph indicated by a one-dot chain line in FIG. 1 shows the time change of the target rotation speed when the deviation restriction process is not executed, and the graph indicated by a two-dot chain line shows the time change of the actual rotation speed when the deviation restriction process is not executed.

[0100] When the deviation limit processing is not performed, such as Fig. 9 In the graph indicated by the single-point chain line in FIG. 1 , in the power running control when the vehicle 1 is in the forward driving state in the low speed mode, the target speed changes at the first change rate α as time passes until the target speed reaches the first limit speed Mf_lim. In this case, when the user operates the brake lever 19 to apply the mechanical brake to the vehicle 1, as shown in FIG. Fig. 9 In the graph indicated by the two-dot chain line in FIG. 1 , the actual speed does not follow the target speed and remains zero. Therefore, the deviation between the target speed and the actual speed increases. When the user releases the brake operation after the target speed reaches the first limit speed Mf_lim, since the deviation between the actual speed and the target speed is large, the required torque Tr calculated from the deviation becomes excessive, and the actual speed increases sharply to greatly exceed the first limit speed Mf_lim.

[0101] When the deviation limiting process is executed, the change of the target speed is limited so that the deviation δ between the target speed and the actual speed does not exceed the first deviation limiting value Df. Fig. 9 In the graph indicated by the solid line in the middle, the deviation δ between the target speed and the actual speed increases, and when the deviation reaches a predetermined first deviation limit value Df, the target speed is maintained at the first deviation limit value Df. When the user releases the brake operation in a state where the target speed is maintained at the first deviation limit value Df, the required torque Tr is calculated from the first deviation limit value Df. Fig. 9 As indicated by the middle dashed line, since the deviation δ between the target rotation speed and the actual rotation speed is limited to the first deviation limit value Df, the actual rotation speed can be prevented from exceeding the first limit rotation speed Mf_lim.

[0102] Although Fig. 9 The deviation limiting process of the rotation speed control performed in the forward driving state is shown, and the deviation limiting process is also performed in the rotation speed control performed in the backward driving state. However, as described in (iv), the absolute value of the deviation limiting value is different between the deviation limiting process in the forward driving state and the deviation limiting process in the backward driving state. In the deviation limiting process when the vehicle 1 is in the forward driving state, the deviation between the target rotation speed and the actual rotation speed is limited to the first deviation limiting value Df, and in the deviation limiting process when the vehicle 1 is in the backward driving state, the deviation between the target rotation speed and the actual rotation speed is limited to the second deviation limiting value Dr. The absolute value of the first deviation limiting value Df in the forward driving state is greater than the absolute value of the second deviation limiting value Dr in the backward driving state.

[0103] Back to Figure 7 , the deviation acquisition unit 55 acquires the target rotation speed whose deviation is limited by the deviation restriction unit 54, and acquires the actual rotation speed in which the noise is removed by the change rate restriction unit 51 and the filter processing unit 52. The deviation restriction unit 54 subtracts the acquired actual rotation speed from the acquired target rotation speed to acquire the deviation between the target rotation speed and the actual rotation speed.

[0104] The PID control unit 56 performs proportional-integral-differential (PID) processing on the deviation δ acquired by the deviation acquisition unit 55. Specifically, the PID control unit 56 calculates the PID control torque by adding a value obtained by multiplying the deviation δ by a proportional gain, a value obtained by multiplying a value obtained by integrating the deviation δ by an integral gain, and a value obtained by multiplying a value obtained by differentially acquiring the deviation δ by a differential gain. A value obtained by adding the offset torque acquired by the offset torque acquisition unit 57 to the PID control torque acquired by the addition unit 58 is determined as the required torque Tr.

[0105] The PID control unit 56 performs a process for rapidly reducing the absolute value of the actual speed when the absolute value of the actual speed exceeds the absolute value of the target speed. Specifically, when the value obtained by subtracting the absolute value of the target speed from the absolute value of the actual speed is less than a threshold value, the PID control unit 56 performs a normal PID process (which may also be referred to as a normal speed control), and in the case where it is determined that a high-speed processing switching condition is satisfied, the PID control unit 56 switches from the normal PID process to a high-speed PID process (which may also be referred to as a high-speed speed control) for rapidly reducing the absolute value of the actual speed compared to the case where the normal PID process is performed. The high-speed processing switching condition is a condition in which the absolute value of the actual speed exceeds the absolute value of the target speed, where the difference is equal to or greater than the threshold value.

[0106] In the present embodiment, the high-speed PID processing is a processing for clearing the integral value obtained by integrating the deviation δ. However, the high-speed PID processing is not limited to the deletion of the integral value, and may be any processing as long as the absolute value of the actual rotation speed is rapidly reduced compared with the case where the normal PID processing is performed. For example, in the high-speed PID processing, the proportional gain may be increased or the integral gain may be reduced compared with the normal PID processing. In the high-speed PID processing, the value obtained by multiplying the deviation δ by the proportional gain, the value obtained by multiplying the value obtained by integrating the deviation δ by the integral gain, and the value obtained by multiplying the value obtained by differentiating the deviation δ by the differential gain may be reduced by a predetermined torque to obtain the PID control torque.

[0107] As described above, when the condition that the absolute value of the actual speed exceeds the absolute value of the target speed by a difference equal to or greater than the threshold value, i.e., the high-speed processing condition, is satisfied, the normal PID processing is switched to the high-speed PID control, but the absolute value of the threshold value of the high-speed processing switching condition is different when the vehicle 1 is in the forward driving state and when the vehicle 1 is in the reverse driving state, as described in (v) above. The absolute value of the first threshold value of the high-speed processing switching condition in the power running control when the vehicle 1 is driving forward is greater than the absolute value of the second threshold value of the high-speed processing switching condition in the power running control when the vehicle 1 is driving reversely.

[0108] The offset torque acquisition unit 57 acquires the offset torque. The offset torque is a torque added to the PID control torque to improve the driving responsiveness of the vehicle 1 when the motor speed is low, such as when the vehicle 1 starts. The offset torque is obtained by referring to an offset torque map pre-stored in the memory. The offset torque map shows the correspondence between the motor speed and the torque.

[0109] Fig.10 is an example of an offset torque diagram. Fig.10 In FIG. 6 , the horizontal axis represents the absolute value of the actual rotation speed of the electric motor 6 , and the vertical axis represents the absolute value of the offset torque. Fig.10 The graph indicated by the solid line in FIG. 1 shows a first offset torque map used in the rotation speed control when the vehicle 1 is in the forward driving state, and Fig.10 The graph indicated by the dotted line in FIG. 8 shows a second offset torque map used in the rotation speed control when the vehicle 1 is in the backward traveling state.

[0110] In both the first offset torque map and the second offset torque map, the absolute value of the torque gradually increases as the absolute value of the actual rotation speed decreases. The offset torque corresponding to a motor rotation speed of a certain value or more is zero.

[0111] As described in (vi) above, the offset torque is different between the speed control performed in the forward driving state and the speed control performed in the reverse driving state. That is, the first offset torque map and the second offset torque map have offset torque values ​​with different absolute values ​​relative to the actual speed. The absolute value of the first offset torque obtained by referring to the first offset torque map when the vehicle 1 is in the forward driving state is greater than the absolute value of the second offset torque obtained by referring to the second offset torque map when the vehicle 1 is in the reverse driving state.

[0112] Back to Figure 7 The required torque Tr obtained by adding the offset torque to the PID control torque through the adding unit 58 is sent to the torque limiting unit 43.

[0113] (Low speed torque control)

[0114] Next, the torque control process performed by the low-speed torque control unit 42d will be described. Figure 7 As shown, the low-speed torque control unit 42d includes a torque determination unit 59. The torque determination unit 59 obtains the regenerative torque corresponding to the motor speed detected by the speed sensor 22. Specifically, the memory of the controller 31 stores the correspondence information indicating the correspondence between the motor speed and the torque. The correspondence information may be, for example, a torque map or an arithmetic expression. The correspondence information may be information indicating at least the correspondence between the motor speed and the torque (that is, the regenerative torque). For example, the correspondence information may indicate the correspondence between the accelerator operation amount, the motor speed and the torque. The low-speed torque control unit 42d and the normal driving control unit 41 may refer to the same correspondence information (for example, a torque map) or may refer to different correspondence information. The torque determination unit 59 refers to the correspondence information, obtains the regenerative torque corresponding to the motor speed indicated by the received motor speed information, and determines the torque as the required torque Tr required by the electric motor 6. The required torque Tr determined by the torque determination unit 59 is sent to the torque limiting unit 43.

[0115] (Torque limit processing)

[0116] Will refer to Fig.11 The torque limiting process performed by the torque limiting unit 43 is described. Fig.11 yes Figure 3 The torque limiting unit 43 includes a limiting current obtaining unit 61, a limiting torque calculating unit 62 and a comparing unit 63.

[0117] The limit current acquisition unit 61 determines the limit current based on the battery temperature information received from the temperature sensor 3b and the SOC information received from the battery management unit 3c. The memory of the controller 31 stores correspondence information indicating the correspondence between the battery temperature and the SOC and the correspondence between the charge current limit value Ic and the discharge current limit value Id. The limit current acquisition unit 61 refers to the correspondence information to acquire the charge current limit value Ic and the discharge current limit value Id corresponding to the received battery temperature and SOC. The charge current limit value Ic is the maximum allowable charge current set in the received battery temperature and SOC, and the discharge current limit value Id is the maximum allowable discharge current set in the received battery temperature and SOC.

[0118] The limiting torque calculation unit 62 calculates the charging limiting torque Tc from the charging current limiting value Ic acquired by the limiting current acquisition unit 61. Specifically, the limiting torque calculation unit 62 calculates the charging limiting power by multiplying the charging current limiting value Ic by the voltage of the battery 3a, and divides the calculated charging limiting power by the actual rotation speed of the electric motor 6 to obtain the charging limiting torque Tc. By setting the regenerative torque generated in the electric motor 6 during the regenerative control to be equal to or less than the charging limiting torque Tc, the charging current to the battery 3a is maintained equal to or less than the charging current limiting value Ic. This charging limiting torque Tc may also be referred to as the regenerative limiting torque Tc. That is, the regenerative limiting torque Tc is the torque when the current flowing into the battery 3a becomes the maximum allowable charging current.

[0119] The limiting torque calculation unit 62 calculates the discharge limiting torque Td from the discharge current limiting value Id acquired by the limiting current acquisition unit 61. Specifically, the limiting torque calculation unit 62 calculates the discharge limiting power by multiplying the discharge current limiting value Id by the voltage of the battery 3a, and divides the calculated discharge limiting power by the actual rotation speed of the electric motor 6 to obtain the discharge limiting torque Td. By setting the drive torque generated in the electric motor 6 during the power running control to be equal to or less than the discharge limiting torque Td, the discharge current from the battery 3a is kept equal to or less than the discharge current limiting value Id. This discharge limiting torque Td may also be referred to as the power running limiting torque Td. That is, the power running limiting torque Td is the torque when the current flowing out of the battery 3a becomes the maximum allowable discharge current.

[0120] In this way, the power running limit torque Td and the regeneration limit torque Tc are changed based on the battery state information related to the state of the battery 3a, that is, the battery temperature information and the SOC information. For example, the power running limit torque Td and the regeneration limit torque Tc can be set to decrease as the temperature of the battery 3a increases. For example, the regeneration limit torque Tc is set to decrease as the SOC approaches 100%. This is to avoid overcharging of the battery 3a. In this embodiment, under the conditions of the same SOC and the same battery temperature, the power running limit torque Td is greater than the regeneration limit torque Tc.

[0121] The comparison unit 63 compares the required torque Tr determined by the low speed rotation control unit 42c or the low speed torque control unit 42d with the limit torque calculated by the limit torque calculation unit 62. That is, the comparison unit 63 compares the required torque Tr with the power running limit torque Td during the power running control, and compares the required torque Tr with the regeneration limit torque Tc during the first regeneration control or the second regeneration control. In the case where it is determined that the absolute value of the required torque Tr does not exceed the absolute value of the limit torque, the comparison unit 63 outputs a control command to the inverter 32 so that the electric motor 6 generates the required torque Tr. In the case where it is determined that the absolute value of the required torque Tr exceeds the absolute value of the limit torque, the comparison unit 63 outputs a control command to the inverter 32 so that the electric motor 6 generates the limit torque.

[0122] The comparison unit 63 limits the torque in the positive direction or negative direction required by the electric motor 6 during the power running control to the power running limit torque Td or less. The comparison unit 63 limits the torque in the positive direction or negative direction required by the electric motor 6 during the regeneration control to the regeneration limit torque Tc or less. Therefore, as described in (vii) above, the absolute value of the upper limit torque (which is the limit torque of the electric motor 6 in the positive direction) and the absolute value of the lower limit torque (which is the limit torque of the electric motor 6 in the negative direction) are different between the speed control performed in the forward driving state and the speed control performed in the reverse driving state.

[0123] Specifically, the comparison unit 63 obtains the power running limit torque Td and the regeneration limit torque Tc calculated by the limit torque calculation unit 62. In the case where it is determined that the vehicle state is the forward driving state, the comparison unit 63 sets the obtained power running limit torque Td as the upper limit torque and the obtained regeneration limit torque Tc as the lower limit torque. That is, when the vehicle state is the forward driving state, the comparison unit 63 limits the magnitude of the driving torque generated by the electric motor 6 in the positive direction so as not to exceed the power running limit torque Td, and limits the magnitude of the regeneration torque generated by the electric motor 6 in the negative direction so as not to exceed the regeneration limit torque Tc.

[0124] On the other hand, in the case where it is determined that the vehicle state is the backward traveling state, the comparison unit 63 sets the acquired regeneration limit torque Tc as the upper limit torque and the acquired power running limit torque Td as the lower limit torque. That is, when the vehicle state is the backward traveling state, the comparison unit 63 limits the magnitude of the regeneration torque generated by the electric motor 6 in the positive direction so as not to exceed the regeneration limit torque Tc, and limits the magnitude of the drive torque generated by the electric motor 6 in the negative direction so as not to exceed the power running limit torque Td.

[0125] However, in the present embodiment, as an exception, the comparison unit 63 determines whether the vehicle state is a predetermined low-speed driving state, and in the case where the vehicle state is determined to be the low-speed driving state, the comparison unit 63 performs a torque limit reduction process for reducing the limit on the required regeneration torque Tr compared to the case where the vehicle state is determined not to be the low-speed driving state. In other words, the comparison unit 63 sets the regeneration limit torque Tc set in the case where the vehicle state is determined to be the low-speed driving state to be greater than the regeneration limit torque Tc calculated by the limit torque calculation unit 62 in the case where the vehicle state is determined not to be the low-speed driving state.

[0126] For example, the low-speed driving state is a state in which the regeneration amount in the electric motor 6 is a predetermined value or less. The low-speed driving state may be, for example, a state in which the absolute value of the motor rotation speed is a predetermined value or less. The low-speed driving state includes a stopped state of the vehicle 1 in which the absolute value of the motor rotation speed is zero.

[0127] In the present embodiment, the reason for reducing the limit of the required regenerative torque Tr when the vehicle state is a low-speed driving state will be described. For example, when the battery 3a is fully charged, in order to prevent overcharging, the regenerative limit torque Tc calculated by the limit torque calculation unit 62 is zero or substantially zero. Assume that the battery 3a is temporarily fully charged and the vehicle 1 is traveling forward at a low speed (for example, a vehicle speed of 1 km or less). Assume that the user performs a backward driving operation in this state. In this case, since the vehicle 1 is in a forward driving state, the limit torque of the electric motor 6 in the negative direction is zero or substantially zero regenerative limit torque. Therefore, although the user performs a backward driving operation, no torque is generated in the negative direction of the electric motor 6. On the other hand, when the vehicle 1 is at an extremely low speed, since the regeneration amount is substantially zero, in the state where the vehicle 1 is traveling at a low speed without generating a regenerative torque, even if the regenerative torque of the electric motor 6 is not limited, the battery will not be overcharged. This is the reason for reducing the limit of the required regenerative torque Tr when the vehicle state is a low-speed driving state.

[0128] Specifically, the comparison unit 63 determines whether the vehicle state is a low-speed driving state based on the rotation speed detected by the rotation speed sensor 22. In response to determining that the vehicle 1 is in a low-speed driving state, the comparison unit 63 sets the magnitude of the regeneration limit torque Tc to the same magnitude as the power operation limit torque Td calculated by the limit torque calculation unit 62 based on the SOC and the battery temperature, rather than the magnitude of the regeneration limit torque Tc calculated by the limit torque calculation unit 62. In other words, both the upper limit torque and the lower limit torque are set to the power operation limit torque Td. Therefore, the restriction on the regeneration torque is reduced. This is because, even when the battery 3a is fully charged, the power operation limit torque Td is not zero or substantially zero like the regeneration limit torque Tc, and is a relatively large value.

[0129] However, in the process for reducing the restriction on the regenerative torque, instead of setting the value of the regenerative limit torque Tc to the same value as the power operation limit torque Td calculated by the limit torque calculation unit 62, the regenerative limit torque Tc may not be set, or may be a predetermined torque greater than the regenerative limit torque Tc calculated by the limit torque calculation unit 62.

[0130] (Operation and Effect)

[0131] As described above, according to the present embodiment, the controller 31 is configured to switch between the power running control and the regeneration control based on the vehicle state information and the operation information. Therefore, it is possible to implement a driving control suitable for each state of the forward / reverse driving state of the vehicle and the user's operation. Therefore, it is possible to make the feeling felt by the user when the vehicle is operated to drive close to the feeling expected by the user.

[0132] According to the present embodiment, in the case where it is determined that the vehicle state is the forward driving state and the user operation is the backward driving operation, or in the case where it is determined that the vehicle state is the backward driving state and the user operation is the forward driving operation, the controller 31 performs the second regeneration control for generating a regenerative braking force greater than the regenerative braking force generated in the first regeneration control in the case where it is determined that the user operation is the reference position operation. Therefore, regeneration reflecting the user's intention is easily achieved.

[0133] According to the present embodiment, the controller 31 performs rotation speed control so that the rotation speed of the electric motor 6 is zero in the second regeneration control. Therefore, regeneration reflecting the user's intention is easily achieved.

[0134] In addition, according to the present embodiment, the controller 31 is configured so that the operator 15a that receives the user's forward travel operation and the reverse travel operation is an accelerator grip, returns to a predetermined reference position when no user operation is performed, moves from the reference position in a first moving direction in response to the user's forward travel operation, and moves from the reference position in a second moving direction different from the first moving direction in response to the user's reverse travel operation. As described above, since the forward travel and the reverse travel of the vehicle 1 can be performed by the operation of the operator 15a, the forward travel command and the reverse travel command are prevented from being generated at the same time, and the operability is improved.

[0135] According to the present embodiment, the controller 31 obtains different regeneration amounts between the second regeneration control when the vehicle state is the forward driving state and the second regeneration control when the vehicle state is the backward driving state. Therefore, the regeneration amount can be appropriately adjusted between the case where the vehicle is in the forward driving state and the case where the vehicle is in the backward driving state.

[0136] According to the present embodiment, the controller 31 determines that the required torque required by the electric motor 6 at the time of power running control is equal to or less than the power running limit torque, and determines that the required torque required by the electric motor at the time of regeneration control is equal to or less than the regeneration limit torque, which has a magnitude different from that of the power running limit torque. Therefore, by making the range of the torque required by the electric motor 6 different between the power running control and the regeneration control, the required torque can be adjusted within an appropriate range. Therefore, for example, the discharge current of the battery 3a and the charge current of the battery 3a can be adjusted within a range suitable for the specifications of the battery 3a.

[0137] According to the present embodiment, the controller 31 acquires battery status information related to the state of the battery 3a, and changes the power running limit torque or the regeneration limit torque based on the battery status information. The discharge current of the battery 3a and the charge current of the battery 3a can be adjusted within a range suitable for the state of the battery.

[0138] When the SOC of the battery is 100%, it is not preferable to further supply the charging current to the battery, and therefore, generally speaking, the regeneration limit torque, which is a limiting value used during regeneration control, is set to zero. That is, when the SOC of the battery is 100%, regeneration braking force is generally not generated. On the other hand, when the motor speed is small, the electromotive force of the motor is small, and the charging current is small. According to the present embodiment, the controller 31 determines whether the vehicle state is a low-speed driving state in which the regeneration amount is equal to or less than a predetermined value based on the vehicle state information during regeneration control, and increases the regeneration limit torque setting in the case where the vehicle state is determined to be a low-speed driving state compared to the regeneration limit torque setting in the case where the vehicle state is determined not to be a low-speed driving state. Therefore, even when the SOC of the battery is temporarily 100%, regeneration braking force can be generated.

[0139] <Other embodiments>

[0140] The present disclosure is not limited to the above-described embodiments, and the configuration may be changed, added, or deleted.

[0141] For example, the vehicle described in the above embodiment is an electric vehicle including a driving source for traveling, but the vehicle is not limited to this. The present disclosure is applicable to any vehicle including a driving source for traveling forward / backward. For example, the vehicle may be a hybrid vehicle including two driving sources for traveling forward / backward including an electric motor and an internal combustion engine. The vehicle may include a separate driving source as long as the vehicle includes a motor for traveling forward / backward. In addition, the straddle-type vehicle may not be a two-wheeled vehicle but may be a three-wheeled vehicle. In addition, the vehicle may not be a straddle-type vehicle and may be, for example, a four-wheeled vehicle. The vehicle may include a transmission device for switching the transmission ratio of the transmission device. The vehicle may include a transmission device capable of switching the reduction ratio. In addition, the vehicle may include an operator for receiving a transmission gear position operation performed by a user.

[0142] In the above-described embodiment, the mode switching between the normal driving mode and the low-speed mode is performed according to the operation of the mode switching switch, but the present disclosure is not limited thereto. That is, the mode switching may be performed according to a predetermined mode switching condition. For example, instead of a dedicated mode switching switch, the mode switching may be performed by determining that a plurality of existing switches are operated simultaneously. The condition for switching from the normal driving mode to the low-speed mode may be different from the condition for switching from the low-speed mode to the normal driving mode.

[0143] In the above embodiment, the forward driving operation or the reverse driving operation of the user in the low speed mode is an operation for the torque command operator 15a, and the forward driving operation or the reverse driving operation in the low speed mode can be performed for a torque command operator different from the torque command operator 15a. The operator for the forward driving operation and the operator for the reverse driving operation can be set separately.

[0144] The operation information indicating the operation content of the user may include information indicating whether the normal driving mode or the low speed mode is selected as the control mode. In other words, the user operation of the forward driving operation or the reverse driving operation performed by the user may also serve as the selection operation of the low speed mode.

[0145] For example, the vehicle may include a low-speed forward button and a low-speed backward button, and the operation of pressing the low-speed forward button may be a forward driving operation in the low-speed mode, and the operation of pressing the low-speed backward button may be a backward driving operation in the low-speed mode. For example, the vehicle may include a lever for low-speed operation, and the forward driving operation or the backward driving operation in the low-speed mode may be performed on the lever for low-speed operation. In this case, the lever for low-speed operation may be tilted forward and backward from the reference position, and the forward tilting operation may be the forward driving operation and the backward tilting operation may be the backward driving operation. The lever for low-speed operation may be movable in an L-shape.

[0146] In the above-described embodiment, the absolute values ​​of the setting values ​​of the parameters (i) to (vii) are different between the control performed in the forward driving state and the control performed in the reverse driving state, but for some of these parameters, the absolute values ​​of the setting values ​​may be the same between the control performed in the forward driving state and the control performed in the reverse driving state. For example, in the above-described embodiment, the start-up change rates α1 and β1 and the driving change rates α2 and β2 are set respectively, but the corresponding change rates α and β may be set for the forward driving and the reverse driving without distinction. Some of the parameters (i) to (vii) may not be set, and the absolute values ​​of the setting values ​​of other parameters may be different between the control performed in the forward driving state and the control performed in the reverse driving state.

[0147] In the normal driving mode, the output can be changed according to the torque command operator 15a, and the torque, the driving speed, or the motor speed can be changed. For example, in the normal driving mode, instead of performing torque control for determining the required torque based on the correspondence information indicating the correspondence between the accelerator operation amount and the torque described in the above embodiment, feedback control for making the actual vehicle speed close to the target vehicle speed can be performed, or feedback control for making the actual motor speed close to the target motor speed can be performed.

[0148] In the normal travel mode, when the reverse travel operation is performed while the vehicle 1 is stopped, that is, when the torque command operator 15a is pivoted from the reference position in the second moving direction R2 by the second angle or more, the vehicle 1 may not travel backward. In the normal travel mode, when the reverse travel operation is performed while the vehicle 1 is traveling forward, that is, when the torque command operator 15a is pivoted from the reference position in the second moving direction R2 by the second angle or more, a regenerative braking force may be generated in the electric motor 6, as in the second regenerative control in the low speed mode described later.

[0149] In the low speed mode, the travel speed may be reduced compared to the normal travel mode, and the torque, travel speed, or motor speed may be limited. For example, in the low speed mode, instead of executing feedback control for making the actual motor speed close to the target motor speed described in the above embodiment, feedback control for making the actual vehicle speed close to the target vehicle speed may be executed, or control for gradually changing the output torque of the electric motor 6 may be executed.

[0150] For example, the controller 31 may be configured to change the output torque of the electric motor in a positive direction at a first change rate when determining that the user operation is a forward driving operation, and change the output torque of the electric motor in a negative direction at a second change rate when determining that the user operation is a backward driving operation. In this case, the absolute value of the first change rate may be greater than the absolute value of the second change rate.

[0151] The present disclosure is also applicable to a vehicle that does not have a low speed mode as a control mode. The present disclosure is applicable to a vehicle that can travel forward or backward according to a user operation. The controller 31 may have a control mode other than the modes described in the above embodiment.

[0152] The control mode of the controller in a vehicle capable of forward / reverse travel may be a travel mode in which the vehicle acceleration in the forward travel direction when the user operation is determined as a forward travel operation is different from the vehicle acceleration in the reverse travel direction when the user operation is determined as a reverse travel operation. In this case, the absolute value of the vehicle acceleration in the forward travel direction may be set to be greater than the absolute value of the vehicle acceleration in the reverse travel direction.

[0153] In the above embodiment, when the vehicle state is the forward driving state or the backward driving state and the user operation is the reference position operation in the low speed mode, torque control using the correspondence information indicating the correspondence between the motor speed and the torque is performed, but in this case, speed control instead of torque control may be performed. That is, the first regeneration control may be speed control. In other words, in the low speed mode, in the case of the reference position operation in the state of vehicle driving, speed control may be performed by the low speed control unit 42c so that the target speed gradually decreases at a predetermined third change rate γ. In this case, the change rate between forward driving and backward driving may also be made different.

[0154] The control methods of the first regeneration control and the second regeneration control are not limited to those described in the above-mentioned embodiments. The amount of regeneration performed by the second regeneration control may be greater than the amount of regeneration performed by the first regeneration control. For example, in the above-mentioned embodiment, in the second regeneration control, the target speed is set to zero, but the target speed may be reduced to near zero at a predetermined rate of change. In this case, in the first regeneration control, the target speed may be reduced to near zero at a rate of change having an absolute value smaller than the absolute value of the rate of change in the second regeneration control.

[0155] In the above-mentioned embodiment, even in the same control form, the absolute values ​​of the setting values ​​of parameters (i) to (vii) are different depending on whether the vehicle state is a forward driving state or a reverse driving state, but the absolute values ​​of one or more of the setting values ​​of parameters (i) to (vii) may be the same between the forward driving state and the reverse driving state.

[0156] The present disclosure is also applicable to a case where processing related to some of the parameters (i) to (vii) is not performed.

[0157] For example, in the speed control in the low speed mode of the above embodiment, the time series data of the actual speed of the electric motor 6 is subjected to the rate of change limiting filtering process, but only the time series data of the actual speed of the electric motor 6 may be subjected to the low-pass filtering process without the rate of change limiting filtering process.

[0158] For example, in the rotation speed control in the low speed mode according to the above embodiment, the deviation limiting process for limiting the change of the target rotation speed is performed so that the deviation between the target rotation speed and the actual rotation speed does not exceed the predetermined deviation limit value, but the deviation limiting process may not be performed.

[0159] For example, in the speed control in the low speed mode according to the above-mentioned embodiment, when the absolute value of the actual speed exceeds the absolute value of the target speed and the difference is equal to or greater than the threshold value, the normal PID processing is switched to the high-speed PID processing to quickly reduce the absolute value of the actual speed, compared with the case where the normal PID processing is performed.

[0160] In the above-described embodiment, the controller 31 acquires motor speed information indicating the motor speed from the speed sensor 22 that detects the speed of the output shaft of the electric motor 6, but the method of acquiring the motor speed information is not limited thereto. For example, the vehicle may include a wheel speed sensor that detects the speed of the drive wheel, and the controller 31 may calculate the speed of the electric motor 6 based on the wheel speed information received from the wheel speed sensor. The vehicle state information acquisition unit 42a determines whether the vehicle state is a forward driving state or a backward driving state based on the motor speed information, and the determination may be performed from the detection value of the wheel speed sensor. In a state in which the electric motor 6 is stopped, there may be a situation in which the vehicle travels forward and backward due to inertia or a slope. Even in such a case, by determining the vehicle state using the detection value of the wheel speed sensor, the determination accuracy of the vehicle state is improved.

[0161] In the above embodiment, PID feedback control is used as the speed control, but other known feedback controls may be used. Although torque is used as the control amount, the speed control may be performed using other control targets, for example, the battery current. Although feedback control is preferred, the speed of the motor or the rate of change of the output torque when driving forward / reverse may vary depending on the feedforward control. When the current generated by the torque command is less than the allowable current, the function of the torque limiting unit may be omitted.

[0162] In the above embodiment, the comparison unit 63 determines whether the vehicle state is a predetermined low-speed driving state. When the vehicle state is determined to be a low-speed driving state, the restriction on the required regenerative torque Tr is reduced compared to the case where the vehicle state is determined not to be a low-speed driving state, but the controller 31 may not perform such exception processing in the low-speed driving state.

[0163] That is, even when the vehicle state is a low-speed driving state, regeneration can be prohibited. A regeneration prohibition condition for prohibiting regeneration can be set for battery protection. Whether the regeneration prohibition condition is met can be determined based on, for example, the SOC or the battery temperature. The regeneration prohibition condition may include a condition that the SOC is equal to or higher than a predetermined value, or a condition that the battery temperature is equal to or higher than a predetermined temperature. When a regeneration command is given to the controller through user operation, the controller may determine whether the regeneration prohibition condition is met, and may invalidate the regeneration command when the regeneration prohibition condition is met. For example, when the SOC is close to 100% or the battery temperature is in a predetermined regeneration prohibition temperature range, the regeneration command may be invalidated.

[0164] When the vehicle state is a predetermined low-speed driving state, the torque limit reduction process for reducing the limit on the required regenerative torque Tr can be used only for the control of moving the vehicle forward or only for the control of moving the vehicle backward. Specifically, compared with the case where it is determined that the vehicle state is not a low-speed driving state, in the case where it is determined that the vehicle state is one of a low-speed driving state in the forward driving direction and a low-speed driving state in the backward driving direction, the controller can be configured to perform the torque limit reduction process to reduce the limit on the required regenerative torque, and not perform the torque limit reduction process when it is determined that the vehicle state is the other low-speed state. The process for reducing the limit on the required regenerative torque Tr when the vehicle state is a predetermined low-speed driving state is also applicable to vehicles that are not traveling backward.

[0165] In the above embodiment, the regeneration amount by the second regeneration control is greater than the regeneration amount by the first regeneration control regardless of whether the vehicle state is the forward driving state or the reverse driving state, but the regeneration amount by the second regeneration control may be greater than the regeneration amount by the first regeneration control only when the vehicle state is one of the forward driving state and the reverse driving state. When the vehicle state is one of the forward driving state and the reverse driving state, one of the first regeneration control and the second regeneration control may not be performed.

[0166] In the above embodiment, in the state of determining to perform the forward driving operation or the reverse driving operation, the regeneration amount is set to a constant regeneration amount regardless of the operation amount of the torque command operator, but the present disclosure is not limited thereto. For example, the regeneration amount may increase as the operation amount of the torque command operator increases.

[0167] The meter device 18 may display information indicating a regenerative control state in which the regenerative control is executed. In this case, the controller 31 sends a command for displaying the regenerative control state to the meter device 18. In addition, when displaying the regenerative control state, the meter device 18 may make the display mode different between a state in which the regenerative braking is strong and a state in which the regenerative braking is weak. In this case, the controller 31 sends information indicating whether the regenerative braking is strong or weak to the meter device 18.

[0168] The meter device 18 may display information indicating that the control mode is the low speed mode. In this case, the controller 31 sends a command for indicating the low speed mode to the meter device 18. The meter device 18 may display whether the vehicle is in a forward driving state or a reverse driving state in a distinguishable manner when displaying the low speed mode. In this case, the controller 31 sends the vehicle state information to the meter device 18. In addition, the meter device 18 may display whether the user operation is a forward driving operation or a reverse driving operation in a distinguishable manner. In this case, the controller 31 sends operation information indicating the user's operation content of the torque command operator 15a to the meter device 18.

[0169] Each of the control units 41 to 43 may be implemented by a separate circuit. The controller may read a program corresponding to the operation of each control unit to implement the function of each control unit.

[0170] The functions of the elements disclosed in this specification can be performed by using a general-purpose processor, a special-purpose processor, an integrated circuit, an application-specific integrated circuit (ASIC), a circuit of the related art, or a circuit or processing circuit including a combination thereof, and these processors are configured or programmed to perform the disclosed functions. Since the processor includes transistors and other circuits, the processor is considered to be a processing circuit or circuit. In the present disclosure, a circuit, a unit or a device is hardware that performs the listed functions or is programmed to perform the listed functions. The hardware can be the hardware disclosed in this specification, or it can be other known hardware that is configured or programmed to perform the listed functions. When the hardware is a processor that is considered to be a type of circuit, the circuit, device or unit is a combination of hardware and software, and the software is used for the configuration of the hardware or processor.

[0171] The program including the commands for executing the methods disclosed in this specification may be stored in a non-transitory computer-readable storage medium. The non-transitory computer-readable storage medium includes, for example, a disk such as a hard drive, an optical disk such as a CD-ROM, a DVD disk, and a Blu-ray disk, a read-only memory (ROM), a random access memory (RAM), an EPROM, an EEPROM, a magnetic card, a flash memory, an optical card, and any type of medium suitable for storing electronic commands.

[0172] [Example]

[0173] The following aspects are disclosures of preferred embodiments.

[0174] According to a first aspect of the present disclosure, a straddle-type vehicle includes: a vehicle body; an electric motor mounted on the vehicle body as a drive source and rotatable in a forward direction and a reverse direction; a battery mounted on the vehicle body and configured to supply electric power to the electric motor; and a processing circuit configured to control the electric motor. The processing circuit is configured to: acquire vehicle state information capable of determining whether a vehicle state of the straddle-type vehicle is a forward driving state or a backward driving state, and operation information capable of determining whether a user operation is a forward driving operation or a backward driving operation; and switch between power running control and regeneration control based on the vehicle state information and the operation information.

[0175] According to the above configuration, it is possible to realize a travel control suitable for each of the forward / reverse travel state of the vehicle and each state of the user's operation. Therefore, the feeling felt by the user when the vehicle is operated to travel can be made close to the feeling expected by the user.

[0176] According to the second aspect of the present disclosure, in the first aspect, based on the vehicle state information and the operation information, the processing circuit is configured to: perform power operation control when the processing circuit determines that the vehicle state is a forward driving state and the user operation is a forward driving operation, or when the processing circuit determines that the vehicle state is a backward driving state and the user operation is a backward driving operation; and perform regeneration control when the processing circuit determines that the vehicle state is a forward driving state and the user operation is a backward driving operation, or when the processing circuit determines that the vehicle state is a backward driving state and the user operation is a forward driving operation.

[0177] According to a third aspect of the present disclosure, in the first aspect or the second aspect, the operation information is information capable of determining whether the user operation is a reference position operation different from the forward driving operation and the reverse driving operation in addition to whether the user operation is a forward driving operation or a reverse driving operation. The processing circuit is configured to: perform regeneration control when the processing circuit determines that the vehicle state is the forward driving state or the reverse driving state and the user operation is the reference position operation, and perform regeneration control to generate a regenerative braking force greater than the regenerative braking force in the regeneration control when the vehicle state is determined to be the reference position operation when the processing circuit determines that the vehicle state is the forward driving state and the user operation is the reverse driving operation, or when the processing circuit determines that the vehicle state is the reverse driving state and the user operation is the forward driving operation.

[0178] According to the above configuration, reproduction reflecting the user's intention is easily achieved.

[0179] According to a fourth aspect of the present disclosure, in any one of the first to third aspects, when the processing circuit determines that the vehicle state is a forward driving state and the user operation is a reverse driving operation, or when the processing circuit determines that the vehicle state is a reverse driving state and the user operation is a forward driving operation, the processing circuit is configured to perform regeneration control so that the speed of the electric motor is zero.

[0180] According to the above configuration, reproduction reflecting the user's intention is easily achieved.

[0181] According to a fifth aspect of the present disclosure, in any one of the first to fourth aspects, the straddle-type vehicle further includes an operator configured to receive a forward travel operation and a backward travel operation performed by a user. The operator is configured to return to a predetermined reference position when no user operation is performed, to move from the reference position along a first movement direction in response to the user's forward travel operation, and to move from the reference position along a second movement direction different from the first movement direction in response to the user's backward travel operation.

[0182] According to the above configuration, since the forward travel and the reverse travel of the vehicle can be performed by the operation for one operator, the forward travel command and the reverse travel command are prevented from being generated simultaneously, and the operability is improved.

[0183] According to the sixth aspect of the present disclosure, in any one of the first to fifth aspects, the regeneration amount obtained by the regeneration control is different between the case where the processing circuit determines that the vehicle state is a forward driving state and the user operation is a reverse driving operation and the case where the processing circuit determines that the vehicle state is a reverse driving state and the user operation is a forward driving operation.

[0184] According to the above configuration, the regeneration amount can be appropriately adjusted between the case where the vehicle is in the forward traveling state and the case where the vehicle is in the backward traveling state.

[0185] According to the seventh aspect of the present disclosure, in any one of the first to sixth aspects, the processing circuit is configured to: determine that the required torque required by the electric motor is equal to or less than the power operation limiting torque during power operation control; and determine that the required torque required by the electric motor is equal to or less than the regeneration limiting torque during regeneration control, and the regeneration limiting torque has a value different from the power operation limiting torque.

[0186] According to the above configuration, by making the range of torque required by the electric motor different between power running control and regeneration control, the required torque can be adjusted within an appropriate range. Therefore, for example, the battery discharge current and the battery charge current can be adjusted within a range suitable for the battery specifications.

[0187] According to an eighth aspect of the present disclosure, in the seventh aspect, the processing circuit is configured to: acquire battery state information related to a state of the battery; and change the power running limit torque or the regeneration limit torque based on the battery state information.

[0188] According to the above configuration, the discharge current of the battery and the charge current of the battery can be adjusted within a range suitable for the state of the battery.

[0189] According to the ninth aspect of the present disclosure, in the seventh aspect or the eighth aspect, the processing circuit is configured to: determine whether the vehicle state is a low-speed driving state in which the regeneration amount is equal to or less than a predetermined value based on the vehicle state information during regeneration control; and when the processing circuit determines that the vehicle state is a low-speed driving state, increase the regeneration limiting torque setting compared to the regeneration limiting torque setting when the processing circuit determines that the vehicle state is not a low-speed driving state.

[0190] When the SOC of the battery is 100%, it is not preferable to further supply the charging current to the battery, and therefore, generally speaking, the regenerative limit torque, which is a limiting value used in regenerative control, is set to zero. That is, when the SOC of the battery is 100%, regenerative braking force is generally not generated. On the other hand, when the motor speed is small, the electromotive force of the motor is small, and the charging current is small. According to the above configuration, since the regenerative limit torque setting in the case where it is determined that the vehicle state is a low-speed driving state is greater than the regenerative torque limit setting in the case where it is determined that the vehicle state is not a low-speed driving state, regenerative braking force can be generated even when the SOC of the battery is temporarily 100%.

[0191] According to the tenth aspect of the present disclosure, a straddle-type vehicle includes: a vehicle body; an electric motor mounted on the vehicle body as a drive source; a battery mounted on the vehicle body and configured to supply electric power to the electric motor; and a processing circuit configured to control the electric motor. The processing circuit is configured to: determine whether the vehicle state is a low-speed driving state in which the regeneration amount is equal to or less than a predetermined value based on vehicle state information during regeneration control; limit the required regeneration torque, which is the regeneration torque required by the electric motor, when the processing circuit determines that the vehicle state is not a low-speed driving state; and reduce the limitation on the required regeneration torque when the processing circuit determines that the vehicle state is a low-speed driving state compared to when the processing circuit determines that the vehicle state is not a low-speed driving state.

[0192] According to the above configuration, it is easy to maintain regenerative braking even when traveling forward at a low speed.

[0193] According to the eleventh aspect of the present disclosure, a straddle-type vehicle includes: a vehicle body; an electric motor mounted on the vehicle body as a driving source; a battery mounted on the vehicle body and configured to supply electric power to the electric motor; an operator configured to: receive a first movement operation performed by a user and move in a first direction relative to a reference position, and receive a second movement operation performed by a user and move in a second direction relative to the reference position; and a processing circuit configured to control the electric motor. The processing circuit is configured to: perform power operation control when the vehicle state is a driving state and the user operation is a first movement operation; perform first regeneration control when the vehicle state is a driving state and the user operation is a reference position operation; and perform second regeneration control when the vehicle state is a driving state and the user operation is a second movement operation. The amount of regeneration performed by the second regeneration control is greater than the amount of regeneration performed by the first regeneration control.

[0194] According to the above configuration, since the adjustment of the regeneration amount can be performed in two stages by the operation with respect to one operator, the operability is improved.

[0195] According to the twelfth aspect of the present disclosure, a method for controlling a vehicle including an electric motor rotatable in a forward direction and a reverse direction and a processing circuit, the method being executed in the processing circuit, comprises: obtaining vehicle status information capable of determining whether the vehicle status of the vehicle is a forward driving state or a reverse driving state and operation information capable of determining whether a user operation is a forward driving operation or a reverse driving operation; and switching between power operation control and regeneration control based on the vehicle status information and the operation information.

Claims

1. A straddle-type vehicle, comprising: Vehicle body; an electric motor mounted on the vehicle body as a drive source and rotatable in forward and reverse directions; a battery mounted on the vehicle body and configured to supply electric power to the electric motor; as well as a processing circuit configured to control the electric motor, wherein: The processing circuit is configured to: acquiring vehicle state information capable of determining whether the vehicle state of the straddle-type vehicle is a forward driving state or a backward driving state, and operation information capable of determining whether the user operation is a forward driving operation or a backward driving operation; as well as Switching between power running control and regeneration control is performed based on the vehicle state information and the operation information.

2. The straddle-type vehicle according to claim 1, wherein: Based on the vehicle state information and the operation information, the processing circuit is configured to: If the processing circuit determines that the vehicle state is a forward driving state and the user operation is a forward driving operation, or if the processing circuit determines that the vehicle state is a reverse driving state and the user operation is a reverse driving operation, executing power running control; and The regeneration control is performed when the processing circuit determines that the vehicle state is the forward driving state and the user operation is the reverse driving operation, or when the processing circuit determines that the vehicle state is the reverse driving state and the user operation is the forward driving operation.

3. The straddle-type vehicle according to claim 1 or 2, wherein: The operation information is information capable of determining whether the user operation is a reference position operation different from the forward driving operation and the reverse driving operation in addition to whether the user operation is a forward driving operation or a reverse driving operation, and The processing circuit is configured to: In a case where the processing circuit determines that the vehicle state is the forward driving state or the reverse driving state and the user operation is the reference position operation, performing regeneration control, and In a case where the processing circuit determines that the vehicle state is a forward driving state and the user operation is a reverse driving operation, or in a case where the processing circuit determines that the vehicle state is a reverse driving state and the user operation is a forward driving operation, regeneration control is performed to generate a regenerative braking force greater than the regenerative braking force in the regeneration control when the vehicle state is determined to be a reference position operation.

4. The straddle-type vehicle according to claim 1 or 2, wherein: In a case where the processing circuit determines that the vehicle state is a forward driving state and the user operation is a reverse driving operation, or in a case where the processing circuit determines that the vehicle state is a reverse driving state and the user operation is a forward driving operation, the processing circuit is configured to perform regeneration control so that the rotational speed of the electric motor is zero.

5. The straddle-type vehicle according to claim 1 or 2, further comprising: An operator configured to receive the forward driving operation and the backward driving operation performed by a user, wherein: The operator is configured to return to a predetermined reference position when no user operation is performed, to move from the reference position along a first moving direction in response to a forward driving operation performed by the user, and to move from the reference position along a second moving direction different from the first moving direction in response to a backward driving operation performed by the user.

6. The straddle-type vehicle according to claim 1 or 2, wherein: The regeneration amount obtained by the regeneration control differs between a case where the processing circuit determines that the vehicle state is a forward driving state and the user operation is a reverse driving operation and a case where the processing circuit determines that the vehicle state is a reverse driving state and the user operation is a forward driving operation.

7. The straddle-type vehicle according to claim 1 or 2, wherein: The processing circuit is configured to: determining, during the power running control, that a required torque required by the electric motor is equal to or less than a power running limit torque; and A required torque required by the electric motor is determined to be equal to or smaller than a regeneration limit torque having a magnitude different from that of the power running limit torque at the time of the regeneration control.

8. The straddle-type vehicle according to claim 7, wherein: The processing circuit is configured to: Acquiring battery status information related to the status of the battery; and The power running limit torque or the regeneration limit torque is changed based on the battery state information.

9. The straddle-type vehicle according to claim 7, wherein: The processing circuit is configured to: determining, based on the vehicle state information, whether the vehicle state is a low-speed running state in which a regeneration amount is equal to or less than a predetermined value at the time of the regeneration control; as well as The regeneration limiting torque setting in a case where the processing circuit determines that the vehicle state is the low speed running state is increased compared to the regeneration limiting torque setting in a case where the processing circuit determines that the vehicle state is not the low speed running state.

10. A straddle-type vehicle, comprising: Vehicle body; an electric motor mounted on the vehicle body as a driving source; a battery mounted on the vehicle body and configured to supply electric power to the electric motor; as well as a processing circuit configured to control the electric motor, wherein: The processing circuit is configured to: determining whether the vehicle state is a low-speed running state in which the regeneration amount is equal to or less than a predetermined value based on the vehicle state information at the time of regeneration control; limiting a required regenerative torque, which is a regenerative torque required by the electric motor, if the processing circuit determines that the vehicle state is not a low-speed driving state; and The limitation on the required regeneration torque is reduced when the processing circuit determines that the vehicle state is a low-speed driving state compared to when the processing circuit determines that the vehicle state is not a low-speed driving state.

11. A straddle-type vehicle, comprising: Vehicle body; an electric motor mounted on the vehicle body as a driving source; a battery mounted on the vehicle body and configured to supply electric power to the electric motor; An operator, the operator being configured to: receiving a first movement operation performed by a user, and moving along a first direction relative to a reference position; as well as receiving a second movement operation performed by the user, and moving along a second direction relative to the reference position; as well as a processing circuit configured to control the electric motor, wherein: The processing circuit is configured to: executing power running control when the vehicle state is a driving state and the user operation is the first moving operation; executing a first regeneration control when the vehicle state is a running state and the user operation is a reference position operation; as well as executing a second regeneration control when the vehicle state is a driving state and the user operation is the second moving operation, and The regeneration amount performed by the second regeneration control is larger than the regeneration amount performed by the first regeneration control.

12. A method for controlling a vehicle, the vehicle comprising an electric motor capable of rotating in a forward direction and a reverse direction and a processing circuit, the method being performed in the processing circuit, the method comprising: Acquiring vehicle state information capable of determining whether the vehicle state of the vehicle is a forward driving state or a reverse driving state and operation information capable of determining whether a user operation is a forward driving operation or a reverse driving operation; as well as Switching is performed between power running control and regeneration control based on the vehicle state information and the operation information.

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