Electric vehicle and program for controlling electric vehicle

Abstract

To provide an electric vehicle that is configured so that operation of speed change of a manual speed change-type internal combustion engine vehicle can be reproduced, which is improved in driving easiness.SOLUTION: An electric vehicle is provided with an accelerator pedal and a pseudo sequential shifter. The pseudo sequential shifter imitates a sequential shifter that is used in operation of changing speed of a manual speed change-type internal combustion engine vehicle. The electric vehicle executes a manual mode that is selected by a driver. In the manual mode, operation of the pseudo sequential shifter is associated with a virtual shift position that is virtual. Further, in the manual mode, an aperture of the accelerator pedal, the virtual shift position and vehicle speed of the electric vehicle are associated with torque of an electric motor. When a steering angle of a steering wheel becomes equal to a predetermined angle or more during execution of the manual mode, the electric vehicle automatically upshifts the virtual shift position in accordance with the vehicle speed of the electric vehicle.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] The present disclosure relates to a technique for controlling an electric vehicle having an electric motor as a drive source.

Background Art

[0002] Japanese Patent Application Laid-Open No. 2021-151168 discloses a related art of an electric vehicle capable of pseudo-reproducing a manual shifting operation of a vehicle equipped with a manual transmission having an internal combustion engine as a power source (hereinafter referred to as a manual transmission type internal combustion engine vehicle) by controlling an electric motor. The driver of the electric vehicle can select a plurality of virtual gear stages (virtual shift positions) by a paddle switch or the like. The paddle switch is a shift device (hereinafter referred to as a pseudo-sequential shifter) that simulates a sequential shifter provided on the steering wheel.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] According to the above prior art, it is possible to experience a shifting operation of a manual transmission type internal combustion engine vehicle in an electric vehicle. At this time, the driver can select a virtual shift position that reproduces the shift position of the manual transmission type internal combustion engine vehicle by a pseudo-sequential shifter. However, when the pseudo-sequential shifter is provided on the steering wheel, if the steering wheel is greatly steered to steer the electric vehicle, the positional relationship between the hand placed on the steering wheel and the pseudo-sequential shifter changes. Therefore, in a state where the steering angle of the steering wheel is large, it becomes difficult for the driver to smoothly operate the pseudo-sequential shifter.

[0005] The present disclosure has been made in view of the above problems. One object of the present disclosure is to enable a driver to select a mode in an electric vehicle capable of reproducing the shifting operation of a manual transmission internal combustion engine vehicle, in which the driver can experience the operation of the manual transmission internal combustion engine vehicle, and to provide an electric vehicle capable of improving the ease of driving in the mode.

Means for Solving the Problems

[0006] The present disclosure provides an electric vehicle having an electric motor as a drive source. The electric vehicle includes an accelerator pedal used for driving, a pseudo-sequential shifter, and a control device that controls the electric vehicle according to an operation of the accelerator pedal. The pseudo-sequential shifter is an operation member installed on the steering wheel that simulates the sequential shifter used for the shifting operation of a manual transmission internal combustion engine vehicle. The control device is configured to execute the following. The first is to execute a manual mode, which is one of the control modes, by the driver's selection. In the manual mode, the operation of the pseudo-sequential shifter is associated with a virtual shift position, which is a virtual shift position. Also, in the manual mode, the opening degree of the accelerator pedal, the virtual shift position, and the vehicle speed of the electric vehicle are associated with the torque of the electric motor. The second is to automatically upshift the virtual shift position according to the vehicle speed of the electric vehicle when the steering angle of the steering wheel becomes equal to or greater than a predetermined angle during the execution of the manual mode.

[0007] According to one aspect of the present disclosure, the pseudo-sequential shifter may be installed on the steering wheel. Alternatively, the pseudo-sequential shifter may be installed on the steering column.

[0008] In addition, the present disclosure provides a program for controlling an electric vehicle. The electric vehicle has an electric motor as a drive source, and includes an accelerator pedal used for driving, a pseudo-sequential shifter, and a control device that controls the electric vehicle according to an operation of the accelerator pedal. The pseudo-sequential shifter is an operation member installed on a steering wheel that simulates a sequential shifter used for a shifting operation of a manual transmission internal combustion engine vehicle. The program causes a computer to execute the following. The first is to execute a manual mode, which is one of the control modes, by the driver's selection. In the manual mode, the operation of the pseudo-sequential shifter is associated with a virtual shift position, which is a virtual shift position. Also, in the manual mode, the opening degree of the accelerator pedal, the virtual shift position, and the vehicle speed of the electric vehicle are associated with the torque of the electric motor. The second is to automatically upshift the virtual shift position according to the vehicle speed of the electric vehicle when the steering angle of the steering wheel becomes equal to or greater than a predetermined angle during the execution of the manual mode.

Effect of the Invention

[0009] According to the electric vehicle of the present disclosure, when the steering angle of the steering wheel becomes equal to or greater than a predetermined angle in the manual mode, the virtual shift position is automatically upshifted according to the vehicle speed of the electric vehicle. Even in a situation where the steering angle of the steering wheel becomes large and the operation of the pseudo-sequential shifter becomes difficult, it is possible to smoothly upshift at the timing when the driver wants to upshift, and the drivability can be improved.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Embodiments for Carrying Out the Invention

[0011] Embodiments of the present disclosure will be described with reference to the accompanying drawings.

[0012] 1. Configuration of the Power System of an Electric Vehicle FIG. 1 is a diagram schematically showing the configuration of an electric vehicle 100 according to an embodiment of the present disclosure. First, the configuration of the power system of the electric vehicle 100 will be described with reference to FIG. 1.

[0013] The electric vehicle 100 is provided with two electric motors (M) 4F and 4R at the front and rear as driving power sources for running. The electric motors 4F and 4R are, for example, three-phase AC motors. The front electric motor 4F is connected to a front drive shaft 5F that drives the front wheels 6F. The rear electric motor 4R is connected to a rear drive shaft 5R that drives the rear wheels 6R. The front wheels 6F are suspended by an electronically controlled front suspension 7F with independent left and right sides. The rear wheels 6R are suspended by an electronically controlled rear suspension 7R with independent left and right sides.

[0014] An inverter (INV) 3F and 3R are respectively attached to the front electric motor 4F and the rear electric motor 4R. The front inverter 3F and the rear inverter 3R are respectively connected to the battery (BATT) 2. The battery 2 stores the electrical energy for driving the electric motors 4F and 4R. That is, the electric vehicle 100 is a battery electric vehicle (BEV) that runs on the electrical energy stored in the battery 2. The inverters 3F and 3R are, for example, voltage source inverters, and control the torque of the electric motors 4F and 4R by PWM control.

[0015] 2. Configuration of the control system of the electric vehicle Subsequently, the configuration of the control system of the electric vehicle 100 will be described with reference to FIGS. 1 to 3.

[0016] The electric vehicle 100 is equipped with a battery management system (BMS) 10. The battery management system 10 is a device that monitors the cell voltage, current, temperature, etc. of the battery 2. The battery management system 10 has a function of estimating the state of charge (SOC) of the battery 2.

[0017] The electric vehicle 100 is equipped with a vehicle speed sensor 11. At least one of the wheel speed sensors (not shown) provided on each of the left and right front wheels 6F and the left and right rear wheels 6R is used as the vehicle speed sensor 11. In addition, the electric vehicle 100 is equipped with an accelerator pedal stroke sensor 12. The accelerator pedal stroke sensor 12 is provided on the accelerator pedal 22 and outputs a signal indicating the depression amount of the accelerator pedal 22, that is, the accelerator opening. In addition, the electric vehicle 100 is equipped with a brake pedal stroke sensor 13. The brake pedal stroke sensor 13 is provided on the brake pedal 23 and outputs a signal indicating the depression amount of the brake pedal 23, that is, the brake opening. Furthermore, the electric vehicle 100 is equipped with a steering angle sensor 14. The steering angle sensor 14 is provided on the steering 24 and outputs a signal indicating the steering angle of the steering 24, that is, the rotation angle of the steering wheel.

[0018] The accelerator pedal 22, the brake pedal 23, and the steering 24 are driving operation members used for driving the electric vehicle 100. Separately from these driving operation members, the electric vehicle 100 includes a pseudo-shift operation member that imitates an operation member used for the shift operation of a manual transmission internal combustion engine vehicle. The pseudo-shift operation member includes at least the following pseudo-sequential shifter 25.

[0019] In the present embodiment, the pseudo-sequential shifter 25 is provided on the steering 24. FIGS. 2 and 3 show an example of the pseudo-sequential shifter 25.

[0020] FIG. 2 shows a pseudo-paddle shifter 51 attached to the steering wheel 41 as an example of the pseudo-sequential shifter 25. The pseudo-paddle shifter 51 is a dummy different from the original steering wheel-fixed paddle shifter which is a type of sequential shifter. The pseudo-paddle shifter 51 is composed of a pair of paddles having a structure imitating the shift paddles attached to the steering wheel, and the left and right paddles can be moved independently. Since the pseudo-paddle shifter 51 is fixed to the steering wheel 41, when the steering wheel 41 rotates, the pseudo-paddle shifter 51 also rotates together with the steering wheel 41.

[0021] The pseudo-paddle shifter 51 is provided with a shift switch 15 (see FIG. 1). The shift switch 15 outputs an upshift signal when the right paddle is pulled, and outputs a downshift signal when the left paddle is pulled. Alternatively, the left paddle may correspond to the upshift signal and the right paddle may correspond to the downshift signal. However, since the electric vehicle 100 does not have an actual transmission, the shift positions upshifted or downshifted by the signal from the shift switch 15 are virtual shift positions.

[0022] FIG. 3 shows a pseudo paddle shifter 52 attached to a steering column (steering shaft) 42 as an example of the pseudo sequential shifter 25. The pseudo paddle shifter 52 is a dummy different from the original steering column-fixed paddle shifter. The pseudo paddle shifter 52 is composed of a pair of paddles having a structure imitating a shift paddle attached to the steering column, and the left and right paddles can be moved independently. Since the pseudo paddle shifter 52 is fixed to the steering column 42, the position of the pseudo paddle shifter 52 does not change even when the steering wheel 41 rotates.

[0023] The pseudo paddle shifter 52 is provided with a shift switch 15 (see FIG. 1). When the right paddle is pulled, an upshift signal is output from the shift switch 15, and when the left paddle is pulled, a downshift signal is output from the shift switch 15. Alternatively, the left paddle may correspond to the upshift signal and the right paddle may correspond to the downshift signal.

[0024] As yet another example, the pseudo sequential shifter 25 may be a button installed on the steering wheel 41. The buttons are provided, for example, one on each of the left and right sides of the steering wheel 41. When the right button is pressed, the shift switch 15 outputs an upshift signal, and when the left button is pressed, the shift switch 15 outputs a downshift signal.

[0025] Referring to FIG. 1 again. The electric vehicle 100 includes a human machine interface (HMI) 20 as an interface with the driver and an in-vehicle speaker 21. The HMI 20 includes a touch panel display. The HMI 20 displays information on the touch panel display and receives an input from the driver by a touch operation on the touch panel display. The in-vehicle speaker 21 provides information to the driver by voice and can output a pseudo engine sound described later.

[0026] The electric vehicle 100 is equipped with a control device 101. The sensors and devices to be controlled mounted on the electric vehicle 100 are connected to the control device 101 via an in-vehicle network. In addition to the battery management system 10, vehicle speed sensor 11, accelerator pedal stroke sensor 12, brake pedal stroke sensor 13, steering angle sensor 14, and shift switch 15, various other sensors are mounted on the electric vehicle 100.

[0027] The control device 101 is typically an electronic control unit (ECU). The control device 101 may be a combination of multiple ECUs. The control device 101 includes at least a processor 102 and a memory 103. The memory 103 includes a RAM for temporarily recording data, and a ROM for storing a program 104 executable by the processor 102 and various data 105 related to the program. The program 104 is composed of a plurality of instructions. The processor 102 reads the program 104 and data 105 from the memory 103 and executes them, and generates a control signal based on the signals acquired from each sensor. The number of processors 102 included in the control device 101 may be one or more.

[0028] The control modes in which the control device 101 controls the electric vehicle 100 include a plurality of modes including at least an automatic mode and a manual mode. The control mode can be selected by the driver himself / herself by touching the touch panel display of the HMI 20. Specifically, by touching the touch panel display of the HMI 20, one or more programs 104 associated with each touch operation are read from the memory 103 and executed by the processor 102. Hereinafter, the control modes of the electric vehicle 100 by the control device 101 that can be selected by the driver through the operation of the HMI 20, and the driving control and sound control of the electric vehicle 100 related to the control modes will be described.

[0029] 3. Control Modes of Electric Vehicles FIG. 4 is a tree diagram showing an example of control modes of the electric vehicle 100 selectable by the control device 101. On the HMI 20, a selection screen is displayed on the touch panel display according to the control tree shown in FIG. 4.

[0030] On the initial screen of the HMI 20, an option “Control Mode” OP100 is displayed. By selecting the option “Control Mode” OP100, options “Automatic Mode” OP110 and “Manual Mode” OP120 are displayed on the touch panel display. When the option “Automatic Mode” OP110 is selected, the control mode of the electric vehicle 100 switches to the automatic mode. The automatic mode is a control mode for driving the electric vehicle 100 as a normal BEV. In the automatic mode, the driver can basically drive the electric vehicle 100 only by operating the accelerator pedal 22, the brake pedal 23, and the steering wheel 41. In the automatic mode, the shift operation of the pseudo-sequential shifter 25 is disabled.

[0031] When the option “Manual Mode” OP120 is selected, the control mode of the electric vehicle 100 switches to the manual mode. The manual mode is a control mode for operating the electric vehicle 100 like a manually shifted internal combustion engine vehicle. In the manual mode, the driver performs a shift operation using the pseudo-sequential shifter 25. Then, the operation when the gear ratio of the manually shifted transmission is switched is reproduced by the shift operation of the pseudo-sequential shifter 25. Note that the clutch operation in a genuine sequential shift type manual transmission is automatically performed by a robot. Therefore, even in the manual mode of the electric vehicle 100, the clutch opening is automatically calculated. Note that since the electric vehicle 100 does not have a genuine clutch, the clutch opening calculated in the manual mode is a virtual clutch opening.

[0032] The manual mode may further include a plurality of control modes. The control modes selectable by the driver may include, for example, control modes related to drive modes such as four-wheel drive and rear-wheel drive, and control modes related to the types of engine sounds reproduced by the electric vehicle 100.

[0033] 4. Driving Control of Electric Vehicle FIG. 5 is a diagram showing the configuration of a control device 101 related to the driving control of an electric vehicle 100. Specifically, it shows the configuration related to torque control in particular among the driving controls. When one or a plurality of driving control programs 104 stored in the memory 103 are executed by the processor 102, the processor 102 functions as a driving control device.

[0034] A control mode signal is input to the control device 101 as a driving control device from the HMI 20. The control mode signal includes information regarding the control mode selected by the driver. The control device 101 executes a process P110 based on the control mode signal. In the process P110, the control mode is switched according to the control mode signal. What particularly affects the driving control in the switching of the control mode is the switching between the automatic mode and the manual mode.

[0035] When the control mode is switched to the automatic mode, the control device 101 executes a process P120 for torque calculation in the automatic mode. In the process P120, the control device 101 acquires the vehicle speed from the signal of the vehicle speed sensor 11 and acquires the accelerator opening from the signal of the accelerator pedal stroke sensor 12. The control device 101 has a motor torque map using the accelerator opening and the vehicle speed as parameters. The control device 101 inputs the vehicle speed and the accelerator opening into the motor torque map, and controls the inverters 3F, 3R so as to generate the torque obtained from the motor torque map in the electric motors 4F, 4R.

[0036] When the control mode is switched to the manual mode, the control device 101 executes a process P130 for torque calculation in the manual mode. The process P130 includes a process P131 for calculating the torque to be generated by the drive wheels. The process P130 also includes a process P132 and a process P133. The process P132 is a process for calculating the torque to be generated by the front electric motor 4F, and the process P133 is a process for calculating the torque to be generated by the rear electric motor 4R. The processes P132 and P133 are executed according to the torque distribution between the drive wheel torque calculated in the process P130 and the front wheels 6F and the rear wheels 6R.

[0037] The vehicle model MOD01 is used for calculating the drive wheel torque in the process P131. The vehicle model MOD01 includes an engine model MOD11, a clutch model MOD12, and a transmission model MOD13. The engine virtually realized by the vehicle model MOD01 is referred to as a virtual engine, the clutch virtually realized is referred to as a virtual clutch, and the transmission virtually realized is referred to as a virtual transmission. In the engine model MOD11, the virtual engine is modeled. In the clutch model MOD12, the virtual clutch is modeled. In the transmission model MOD13, the virtual transmission is modeled.

[0038] The engine model MOD11 calculates the virtual engine speed and the virtual engine torque. The virtual engine speed is calculated from the vehicle speed, the overall reduction ratio, and the slip ratio of the virtual clutch. The virtual engine torque is calculated from the virtual engine speed and the accelerator opening. The vehicle speed is obtained from the signal of the vehicle speed sensor 11. The accelerator opening is obtained from the signal of the accelerator pedal stroke sensor 12. The overall reduction ratio is a numerical value obtained by multiplying the gear ratio of the virtual transmission by the reduction ratio determined by the mechanical structure from the virtual transmission to the drive wheels. In the engine model MOD11, the relationship between the virtual engine speed and the virtual engine torque is defined for each accelerator opening. The engine characteristics of the engine model MOD11 may be selectable by the driver through the operation of the HMI20. For example, the engine characteristics may be selectable from among a low and medium rotation type, a high rotation type, and an all-range type.

[0039] The clutch model MOD12 calculates the torque transmission gain. The torque transmission gain is a gain for calculating the degree of torque transmission of the virtual clutch. In the clutch model MOD12, the torque transmission gain is given with respect to the clutch opening. The clutch opening is calculated using the clutch operation model. The clutch operation model is a model that simulates the clutch operation of an exemplary driver. Signals from the vehicle speed, the virtual engine speed, and the shift switch 15 are input to the clutch operation model.

[0040] The signal from the shift switch 15 is used to measure the timing of the clutch operation. When the driver's shift operation is detected by the signal from the shift switch 15, in the clutch operation model, the clutch opening is maximized to disengage the virtual clutch. The vehicle speed and the virtual engine speed are used in the calculation of the clutch opening. In the clutch operation model, the clutch opening is calculated based on the rotational speed difference between the rotational speed of the input shaft of the virtual transmission calculated from the vehicle speed and the virtual engine speed so as to smoothly match them.

[0041] The torque transmission gain calculated by the clutch model MOD12 is converted into the clutch torque capacity of the virtual clutch, that is, the virtual clutch torque capacity. Then, based on the comparison between the virtual clutch torque capacity and the virtual engine torque calculated by the engine model MOD11, the virtual clutch torque input from the virtual clutch to the virtual transmission is calculated. Also, in the clutch model MOD12, the value obtained by subtracting the torque transmission gain from 1 is calculated as the slip ratio. The slip ratio is used in the calculation of the virtual engine speed in the engine model MOD11.

[0042] The transmission model MOD13 calculates the virtual gear ratio. The virtual gear ratio is the gear ratio determined by the virtual shift position in the virtual transmission. The virtual gear ratio is set for each virtual shift position. The maximum virtual gear ratio is set for the first gear, and the virtual gear ratio is decreased in the order of the second gear, third gear, fourth gear, ···. The virtual shift position is shifted up one step when receiving the upshift signal of the shift switch 15, and shifted down one step when receiving the downshift signal of the shift switch 15. Note that there is no physical restriction on the number of shift positions determined by the pseudo-sequential shifter 25. Therefore, for example, the driver may be able to arbitrarily set the number of shift positions through the HMI20.

[0043] The transmission model MOD13 calculates the virtual transmission torque using the virtual gear ratio and the virtual clutch torque. The virtual transmission torque is the virtual torque output from the virtual transmission. The control device 101 controls the inverters 3F, 3R so that the output torques of the electric motors 4F, 4R change according to the virtual transmission torque. The virtual transmission torque changes discontinuously according to the switching of the virtual gear ratio. This discontinuous change in the virtual transmission torque generates a torque shock in the electric vehicle 100, creating the feel of a vehicle equipped with a stepped transmission.

[0044] Vehicle model MOD01 calculates the drive wheel torque from the virtual transmission torque and the reduction ratio. The torque distribution between the front wheels 6F and the rear wheels 6R can be fixed or variable by controlling the electric motors 4F and 4R by the inverters 3F and 3R. When the four-wheel drive mode is selected as the drive mode, the drive wheel torque is the sum of the torques acting on the left and right front wheels 6F and the left and right rear wheels 6R. The torque distribution to the front wheels 6F and the rear wheels 6R can be fixed or changed actively or passively. When the rear-wheel drive mode is selected as the drive mode, the drive wheel torque is the sum of the torques acting on the left and right rear wheels 6R.

[0045] In process P132, the torque of the front electric motor 4F (front motor torque) in the manual mode is calculated by multiplying the drive wheel torque calculated in process P131 by the torque distribution ratio to the front wheels 6F and the reduction ratio from the output shaft of the front electric motor 4F to the front wheels 6F. The control device 101 controls the front inverter 3F so as to generate the front motor torque calculated in process P132 in the front electric motor 4F.

[0046] In process P133, the torque of the rear electric motor 4R (rear motor torque) in the manual mode is calculated by multiplying the drive wheel torque calculated in process P131 by the torque distribution ratio to the rear wheels 6R and the reduction ratio from the output shaft of the rear electric motor 4R to the rear wheels 6R. The control device 101 controls the rear inverter 3R so as to generate the rear motor torque calculated in process P133 in the rear electric motor 4R.

[0047] In the configuration shown in FIG. 5, the battery management system 10 and the brake pedal stroke sensor 13 are not necessarily required for the above-described driving control. However, when the switching of the control mode affects the SOC of the battery 2, the signal of the battery management system 10 may be used as information for determining whether or not to switch the control mode. Further, in a case where the operation method of the electric vehicle 100 changes significantly, such as switching between the automatic mode and the manual mode, it may be a condition for switching that the brake pedal 23 is depressed. In that case, the signal of the brake pedal stroke sensor 13 can be used as information for determining that the brake pedal 23 is depressed.

[0048] 5. Sound control of electric vehicle FIG. 6 is a diagram showing the configuration of a control device 101 related to the sound control of the electric vehicle 100. When one or a plurality of sound control programs 104 stored in the memory 103 are executed by the processor 102, the processor 102 functions as a sound control device. The processor 102 functioning as a torque control device and the processor 102 functioning as a sound control device may be separate processors or the same processor.

[0049] The control device 101 as a sound control device can generate an artificially generated sound from the in-vehicle speaker 21. One of the artificial sounds is a pseudo engine sound imitating the engine sound in a conventional internal combustion locomotive. When a control mode signal indicating that the manual mode has been selected from the HMI 20 is input, the control device 101 as a sound control device executes process P140. In process P140, a pseudo engine sound is generated based on the virtual engine torque and the virtual engine speed calculated in process P131.

[0050] In process P140, a predetermined engine sound is used as the sound source of a pseudo engine sound generated from in-vehicle speaker 21. The type of engine sound may be selectable by the driver on HMI20, for example. However, in process P140, the sound of the sound source is not used as it is. In process P140, for example, the sound pressure of the sound source is changed by an amplifier, and the frequency of the sound source is changed by a frequency modulator, for example.

[0051] Process P140 includes a process P141 for calculating engine sound pressure and a process P142 for calculating engine sound frequency. In process P141, the sound pressure of the pseudo engine sound is calculated from the virtual engine torque using sound pressure map M11. Sound pressure map M11 is created such that the sound pressure increases as the virtual engine torque increases. In process P142, the frequency of the pseudo engine sound is calculated from the virtual engine speed using frequency map M12. Frequency map M12 is created such that the frequency increases as the virtual engine speed increases. The virtual engine torque and the virtual engine speed change according to the driver's accelerator operation, shift operation, and clutch operation. By changing the sound pressure and frequency of the pseudo engine sound according to the changing virtual engine torque and virtual engine speed, a sense of reality can be given to the driver as if driving a real manual transmission internal combustion engine vehicle.

[0052] 6. First Embodiment - Pseudo Sequential Shifter Installed on Steering Wheel 6-1. Automatic Upshift at Steering Start As described above, the driver of electric vehicle 100 can experience the operation of a manual transmission internal combustion engine vehicle in electric vehicle 100 by operating HMI20 to switch the control mode to the manual mode. Even if only the operation feeling of a manual transmission internal combustion engine vehicle is simulated, it can provide sufficient enjoyment for the driver. However, further improvement in convenience is considered.

[0053] As one of the scenarios where the driver may feel inconvenienced, consider the scenario of starting the electric vehicle 100 while steering it after selecting the manual mode. As an example of such a scenario, a scenario where the electric vehicle 100 parked in a parking lot as shown in Fig. 7 is started from the parking space can be considered. In the first embodiment, the case where the pseudo-sequential shifter 25 is the pseudo-paddle shifter 51 installed on the steering wheel 41 is considered.

[0054] When starting, the virtual shift position is in the first gear. The driver steps on the accelerator pedal 22 while steering the steering wheel 41 to increase the virtual engine torque. As the virtual engine torque increases, the pseudo-engine sound becomes louder, and the vehicle speed and the virtual engine speed increase. The driver of a manual transmission internal combustion engine vehicle usually judges how high the engine speed has become based on the magnitude of the engine sound, etc., and upshifts the shift position to the second gear when the engine speed reaches a certain level. The driver of the electric vehicle 100 in the manual mode should also consider upshifting the virtual shift position to the second gear when the vehicle speed reaches a certain level based on the virtual engine speed, etc.

[0055] However, at this time, when the steering wheel 41 is steered, the pseudo-paddle shifter 51 also rotates together, and its position changes. Fig. 7 shows the state of rotation of the steering wheel 41. When the steering wheel 41 is steered and the rotation angle of the steering wheel 41 becomes large up to around 180° like the bottommost state, the left and right of the pseudo-paddle shifter 51 are reversed, and the left paddle corresponds to upshift and the right paddle corresponds to downshift as seen by the driver. Therefore, there may be confusion for the driver as to which paddle corresponds to upshift, and the operation may become difficult. Also, when the rotation angle becomes large, the driver may change the way of holding the steering wheel 41, in which case confusion is more likely to occur and the operation may become difficult due to the change in the way of holding the hand.

[0056] In such a situation, it is possible to continue driving without performing an upshift, but acceleration is smoother when an upshift is performed. Therefore, in the electric vehicle 100 according to the present embodiment, when the virtual engine speed becomes equal to or higher than a predetermined speed in a state where the steering angle of the steering wheel 24 is large, the virtual shift position is automatically upshifted according to the virtual engine speed. Note that the steering angle of the steering wheel 24 can also be referred to as the rotation angle of the steering wheel 41.

[0057] FIG. 8 is a flowchart showing an example of processing executed by the electric vehicle 100. The processing shown in the flowchart of FIG. 8 is realized by one or a plurality of driving control programs 104 stored in the memory 103 being executed by the processor 102.

[0058] According to the flow shown in FIG. 8, first, in step S101, it is determined whether the manual mode is selected as the control mode. If the manual mode is not selected, the flow ends.

[0059] When the manual mode is selected as the control mode, step S102 is executed. In step S102, it is determined whether the rotation angle of the steering wheel 41 is equal to or greater than a predetermined angle. The predetermined angle here is set in advance. If the rotation angle of the steering wheel is less than the predetermined angle, the flow ends.

[0060] When the rotation angle of the steering wheel 41 is equal to or greater than the predetermined angle, step S103 is executed. In step S103, it is determined whether the virtual engine speed is equal to or greater than a predetermined speed. In step S103, the processor 102 may determine that the virtual engine speed is equal to or greater than the predetermined speed when the state where the virtual engine speed is equal to or greater than the predetermined speed continues for a certain time or more, and determine that the virtual engine speed is less than the predetermined speed when the state where the virtual engine speed is equal to or greater than the predetermined speed ends before a certain time has elapsed. If the virtual engine speed is less than the predetermined speed, the flow ends.

[0061] When the virtual engine speed is equal to or higher than a predetermined speed, step S104 is executed. In step S104, the virtual shift position is upshifted from the first gear to the second gear.

[0062] 6-2. Effect According to the above processing, in a scene where the virtual engine speed is increased while the steering angle of the steering 24 is large, such as when starting while turning the steering wheel, an automatic upshift corresponding to the virtual engine speed is performed. This enables smooth acceleration even when it becomes difficult for the driver to grasp the position of the paddle corresponding to the upshift, and can improve drivability.

[0063] 6-3. Predetermined angle The predetermined angle used as the criterion in step S102 is set to an angle close to 180°. When the rotation angle of the steering wheel 41 approaches 180°, the left and right sides of the pseudo paddle shifter 51 are reversed, making it difficult for the driver to grasp the position of the paddle. However, the predetermined angle may be set to, for example, 150° or 120°. Furthermore, based on 90° where the positions of the left and right paddles are reversed left and right with respect to the vertical line passing through the center of the steering wheel 41, it may be considered that the determination in step S102 is established when the rotation angle of the steering wheel 41 becomes 90° or more.

[0064] 7. Second Embodiment - Pseudo Paddle Shifter Installed on the Steering Column The second embodiment is an embodiment in which the pseudo sequential shifter 25 is a pseudo paddle shifter 52 installed on the steering column 42. Similar to the first embodiment, consider a scene where the driver starts the electric vehicle 100 while turning the steering wheel in a state where the manual mode is selected. Also in the second embodiment, there may arise a problem that the upshift cannot be smoothly performed in a scene where the driver wants to upshift.

[0065] FIG. 9 shows the state when the steering wheel 41 rotates. The gray area surrounded by the dashed line is the position where the right hand is placed when the steering wheel 41 is in the initial position. Since it is fixed to the steering column 42, the position of the pseudo paddle shifter 52 itself does not change, but as the steering wheel 41 rotates, the positional relationship with the position of the hand changes, making it difficult for the driver to operate the pseudo paddle shifter 52. For example, when the rotation angle of the steering wheel 41 is around 90°, the position of the right hand moves away from the position of the paddle on the right side of the pseudo paddle shifter 52, making it difficult to perform an upshift operation. As the rotation angle further increases, the position of the right hand and the position of the paddle on the right side of the pseudo paddle shifter 52 become even farther apart. Although the driver may change the way of holding the steering wheel 41 as the rotation angle increases, even if there is a change in the way of holding, the positional relationship between the position of the hand and the pseudo paddle shifter 52 changes compared to when the steering wheel 41 is in the initial position, so it may become difficult to operate the pseudo paddle shifter 52. Therefore, also in the second embodiment, when the manual mode is selected and the steering angle of the steering 24 is greater than a predetermined angle, the electric vehicle 100 automatically upshifts the virtual shift position according to the virtual engine speed.

[0066] The process executed by the electric vehicle 100 can be represented by the flowchart of FIG. 8 in the same manner as in the first embodiment. The processes performed in steps S101 to S104 are the same as in the first embodiment. However, the predetermined angle used for the determination in step S102 is set to a smaller angle than in the case of the first embodiment. In the second embodiment, before the rotation angle of the steering wheel 41 reaches 90°, the position of the right hand moves away from the position of the paddle on the right side of the pseudo paddle shifter 52, causing difficulty in the operation for upshifting for the driver. The predetermined angle may be, for example, 80°.

[0067] Through such processing of the electric vehicle 100, even in a situation where the steering angle of the steering 24 becomes large and it becomes difficult for the driver to operate the pseudo paddle shifter 52, smooth acceleration by upshifting becomes possible. Thus, drivability can be improved.

[0068] 8. Timing of Upshift As described above, the automatic upshift according to the virtual engine speed by the electric vehicle 100 has been explained. In the above example, starting while steering has been cited as an example of a scenario where automatic upshift is applied, but the applicable scenario is not limited to starting. Also, regarding the shift position, it is not limited to the upshift from the first gear to the second gear. Even when not starting, if the virtual engine speed rises to a predetermined speed or higher while the rotation angle of the steering wheel 41 is a predetermined angle or higher, an automatic upshift is performed by the processor 102. Also, when the virtual shift position is second gear or higher, it is upshifted to the shift position one step above. Thereby, similar to starting while steering, smooth acceleration can be enabled even in a situation where the steering angle of the steering 24 becomes large and it becomes difficult for the driver to operate the pseudo sequential shifter 25, and convenience for the driver can be improved.

[0069] It can also be said that the timing at which the automatic upshift is performed is determined according to the vehicle speed. FIG. 10 shows the relationship between the vehicle speed and the virtual engine speed of the electric vehicle 100. Also, the circles represented by the dotted lines indicate the switching timing of the virtual shift position when the automatic upshift is performed. In FIG. 10, the virtual shift position has five steps from the first gear to the fifth gear, but the number of steps of the shift position is an example. As shown in FIG. 10, if there is no operation of the pseudo sequential shifter 25 and the clutch opening is constant, the vehicle speed and the virtual engine speed under a certain shift position have a one-to-one correspondence. Therefore, it can also be said that the upshift timing determined by the virtual engine speed is determined by the vehicle speed corresponding to the shift position.

[0070] 9. Notification to the Driver The fact that the automatic upshift is performed by the electric vehicle 100 may be notified to the driver by the HMI 20. For example, the current shift position may be displayed on the display of the HMI 20, and the driver may be able to know that the shift position has changed by looking at the display.

[0071] Alternatively, the fact that the automatic upshift is performed may not be explicitly notified to the driver. When the virtual shift position changes due to the upshift, the virtual engine torque decreases, and the engine sound discontinuously decreases. Therefore, even without notification by display or the like, the driver can notice the automatic upshift.

Explanation of Reference Numerals

[0072] 2 Battery, 3F Front Inverter, 3R Rear Inverter, 4F Front Electric Motor, 4R Rear Electric Motor, 5F Front Drive Shaft, 5R Rear Drive Shaft, 6F Front Wheel, 6R Rear Wheel, 7F Front Suspension, 7R Rear Suspension, 10 Battery Management System, 11 Vehicle Speed Sensor, 12 Accelerator Pedal Stroke Sensor, 13 Brake Pedal Stroke Sensor, 14 Steering Angle Sensor, 15 Shift Switch, 20 HMI, 21 In-vehicle Speaker, 22 Accelerator Pedal, 23 Brake Pedal, 24 Steering, 25 Virtual Sequential Shifter, 41 Steering Wheel, 42 Steering Column, 51 Virtual Paddle Shifter, 52 Virtual Paddle Shifter, 100 Electric Vehicle, 101 Control Device, 102 Processor, 103 Memory, 104 Program, 105 Data

Claims

1. An electric vehicle having an electric motor as a drive source, an accelerator pedal used for driving the electric vehicle, a pseudo-sequential shifter installed on the steering wheel, which simulates a sequential shifter used for the shifting operation of a manual transmission internal combustion engine vehicle, and a control device for controlling the electric vehicle according to the operation of the accelerator pedal, wherein the control device executes a control mode in which, according to the driver's selection, the operation of the pseudo-sequential shifter is associated with a virtual shift position, which is a virtual shift position, and associates the opening degree of the accelerator pedal, the virtual shift position, and the vehicle speed of the electric vehicle with the torque of the electric motor, and during the execution of the control mode, when the steering angle of the steering wheel becomes equal to or greater than a predetermined angle, automatically upshifts the virtual shift position according to the vehicle speed. An electric vehicle characterized by the above.

2. In the electric vehicle according to Claim 1, the pseudo-sequential shifter is installed on the steering wheel An electric vehicle characterized by the above.

3. In the electric vehicle according to Claim 1, the pseudo-sequential shifter is installed on the steering column An electric vehicle characterized by the above.

4. In the electric vehicle according to Claim 2, the pseudo-sequential shifter is a button installed on the steering wheel An electric vehicle characterized by the above.

5. In the electric vehicle according to Claim 2 or 3, the pseudo-sequential shifter is a pseudo-paddle shifter that simulates a paddle shifter An electric vehicle characterized by the above.

6. In the electric vehicle according to Claim 5, the pseudo-paddle shifter is a pair of paddles attached to the left and right of the steering wheel An electric vehicle characterized by the above.

7. In the electric vehicle according to any one of Claims 1 to 4, further comprising a speaker for outputting a pseudo-engine sound that reproduces the engine sound of the manual transmission internal combustion engine vehicle into the vehicle interior, wherein the control device, during the execution of the control mode, plays the pseudo-engine sound from the speaker, and further associates the opening degree of the accelerator pedal, the virtual shift position, and the vehicle speed with the volume of the pseudo-engine sound. An electric vehicle characterized by the above.

8. In the electric vehicle according to any one of claims 1 to 4, the control device is configured to automatically upshift the virtual shift position from the first gear to the second gear according to the vehicle speed when the steering angle of the steering wheel becomes equal to or greater than a predetermined angle during the execution of the control mode and at the start of the electric vehicle. An electric vehicle characterized by this.

9. A program for controlling an electric vehicle comprising an electric motor as a drive source, an accelerator pedal used for driving, and a pseudo-sequential shifter installed on the steering wheel that simulates a sequential shifter used for the shift operation of a manual transmission internal combustion engine vehicle, controlling the electric vehicle according to the operation of the accelerator pedal; executing a control mode in which, by the driver's selection, the operation of the pseudo-sequential shifter is associated with a virtual shift position that is a virtual shift position, and the opening of the accelerator pedal, the virtual shift position, and the vehicle speed of the electric vehicle are associated with the torque of the electric motor; automatically upshifting the virtual shift position according to the vehicle speed when the steering angle of the steering wheel becomes equal to or greater than a predetermined angle during the execution of the control mode; A program characterized by causing a computer to execute this.

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