Electric vehicle

Abstract

To provide an electric vehicle enabling reproduction of behavior of a transmission vehicle and enabling experience of an operation feeling closer to that of the transmission vehicle while maintaining user-friendliness.SOLUTION: An electric vehicle having an electric motor as a driving source includes: a control device; a first indicator outputting continuous indications according to an operation amount; a second indicator outputting relative indications for every operation; and a third indicator issuing continuous or discrete indications according to the operation amount. The control device is structured so as to execute: switching a relation among a basic torque as a torque of the electric motor, the operation amount of the first indicator and a speed of the electric vehicle from a plurality of predetermined relations according to the operation of the second indicator in a state where the third indicator is not operated; reducing the torque of the electric motor from the basic torque according to the indication from the third indicator; and receiving input from the second indicator only when the operation amount of the third indicator is larger than a predetermined amount.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present disclosure relates to an electric vehicle having an electric motor as a drive source. [Background technology]

[0002] Japanese Patent Publication No. 6787507 discloses an electric vehicle that can virtually reproduce the behavior of a vehicle equipped with a manual transmission (transmission vehicle) powered by an engine by controlling an electric motor. In addition to an EV driving mode (EV mode) for general EV driving, the electric vehicle also has a MT driving mode (MT mode) that reproduces the behavior of a transmission vehicle. The driver can switch between MT mode and EV mode using a switch or the like. In MT mode, the shift position of a transmission vehicle is also virtually reproduced, allowing the driver to manually change gears as if driving a transmission vehicle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6787507 Summary of the Invention [Problem to be solved by the invention]

[0004] According to the above-mentioned conventional technology, it is possible to experience the operation of a transmission vehicle in an electric vehicle. For such an electric vehicle, it is desirable to achieve both an operation feel closer to that of a transmission vehicle and ease of operation.

[0005] One object of the present disclosure is to provide an electric vehicle that can reproduce the behavior of a transmission vehicle, while maintaining ease of operation and at the same time allowing the driver to experience an operating feel similar to that of a transmission vehicle. [Means for solving the problem]

[0006] The present disclosure provides an electric vehicle having an electric motor as a drive source. The electric vehicle includes a control device that controls the electric motor, a first indicator that issues continuous instructions to the control device in response to an operation amount, a second indicator that issues relative instructions to the control device for each operation, and a third indicator that issues continuous or discrete instructions to the control device in response to the operation amount. The control device is configured to switch the relationship between the base torque of the electric motor (torque when the third indicator is not operated), the operation amount of the first indicator, and the vehicle speed of the electric vehicle from among multiple predetermined relationships in response to operation of the second indicator, reduce the torque of the electric motor from the base torque in response to an instruction from the third indicator, and accept an input from the second indicator only when the operation amount of the third indicator is greater than a predetermined amount. [Effects of the Invention]

[0007] According to the electric vehicle of the present disclosure, input from the second indicator is accepted only when the operation amount of the third indicator is greater than a predetermined amount. The third indicator, which issues continuous or discrete instructions depending on the operation amount, corresponds to the clutch pedal in a transmission vehicle. The second indicator, which issues relative instructions for each operation, corresponds to the sequential shifter in a transmission vehicle. In other words, in the electric vehicle of the present disclosure, it is necessary to operate a device that corresponds to the clutch pedal in order to perform an operation that simulates the gear shifting operation of a transmission vehicle. This makes it possible to make the operation feel closer to that of a transmission vehicle. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram illustrating a configuration of an electric vehicle according to an embodiment of the present disclosure. [Figure 2] FIG. 1 is a diagram illustrating an example of a relative indication type shift device. [Figure 3] FIG. 10 is a diagram showing another example of a relative indication type shift device. [Figure 4]FIG. 10 is a diagram showing yet another example of a relative indication type shift device. [Figure 5] FIG. 10 is a diagram showing yet another example of a relative indication type shift device. [Figure 6] FIG. 2 is a diagram showing the configuration of a control device related to driving control of an electric vehicle. [Figure 7] 10 is a time chart showing an example of an operation when an upshift is performed. [Figure 8] 10 is a time chart showing an example of an operation when a downshift is performed. DETAILED DESCRIPTION OF THE INVENTION

[0009] Embodiments of the present disclosure will be described with reference to the accompanying drawings.

[0010] 1. Electric vehicle power system configuration 1 is a diagram schematically illustrating 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.

[0011] The electric vehicle 100 is equipped with two electric motors (M) 4F, 4R at the front and rear as a power source for driving. The electric motors 4F, 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 independent left and right electronically controlled front suspensions 7F. The rear wheels 6R are suspended by independent left and right electronically controlled rear suspensions 7R.

[0012] The front electric motor 4F and the rear electric motor 4R are respectively equipped with inverters (INV) 3F and 3R. The front inverter 3F and the rear inverter 3R are each connected to a battery (BATT) 2. The battery 2 stores electrical energy to drive the electric motors 4F and 4R. In other words, the electric vehicle 100 is a battery electric vehicle (BEV) that runs on electrical energy stored in the battery 2. The inverters 3F and 3R are, for example, voltage-type inverters, and control the torque of the electric motors 4F and 4R by PWM control.

[0013] 2. Electric vehicle control system configuration Next, the configuration of the control system of the electric vehicle 100 will be described with reference to FIGS.

[0014] The electric vehicle 100 is equipped with a vehicle speed sensor 11. At least one of 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. The electric vehicle 100 is also 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, i.e., the accelerator opening. The driver operates the accelerator pedal 22 continuously, and while the electric vehicle 100 is traveling, a signal indicating the accelerator opening is continuously sent to the control device 101. Note that the accelerator pedal 22 is a pedal-type device operated by foot, but the device for operating the accelerator may also be a device operated by hand. For example, the electric vehicle 100 may be equipped with a lever-type accelerator operating device or a dial-type accelerator operating device operated by hand instead of the accelerator pedal 22.

[0015] Furthermore, 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 amount of depression of the brake pedal 23, i.e., the brake opening. The driver operates the brake pedal 23 continuously, and while the electric vehicle 100 is traveling, the signal indicating the brake opening is continuously sent to the control device 101.

[0016] The accelerator pedal 22 and the brake pedal 23 are driving operation members used to drive the electric vehicle 100. In addition to these driving operation members, the electric vehicle 100 is equipped with a gearshift operation member for performing a virtual gearshift operation that simulates the gearshift operation of a transmission vehicle. The gearshift operation member includes a relative instruction type shift device 24 and a pseudo clutch operation device 25 described below.

[0017] The relative instruction shift device 24 is a device that allows the driver to perform gear shifting operations. By operating the relative instruction shift device 24, the driver can specify a shift position (gear stage) relatively; in other words, the driver can select a shift position based on the current shift position. The relative instruction shift device 24 can sequentially shift the shift position up or down one stage at a time. For example, the relative instruction shift device 24 can shift the shift position sequentially from 1st gear, to 2nd gear, to 3rd gear, and so on. The driver selects the desired shift position by sequentially shifting the shift positions. However, because the electric vehicle 100 does not have an actual transmission, the shift position specified by the relative instruction shift device 24 is a virtual shift position.

[0018] There are no particular limitations on the structure of the relative instruction type shift device 24, as long as it is a device that allows the driver to relatively indicate the shift position. Specific examples of the relative instruction type shift device 24 are shown in Figures 2 to 5.

[0019] FIG. 2 shows a pseudo paddle shifter 24 simulating a paddle shifter, a type of sequential shifter, as an example of a relative instruction shift device 24. The pseudo paddle shifter 24 is a dummy that is different from a real paddle shifter. The pseudo paddle shifter 24 has a structure similar to shift paddles attached to the steering wheel 27, and is capable of moving the left and right paddles independently. The pseudo paddle shifter 24 may be attached to the steering wheel or the steering column. (a) shows a pseudo paddle shifter simulating a paddle shifter attached to the steering wheel, and (b) shows a pseudo paddle shifter simulating a paddle shifter attached to the steering column. The pseudo paddle shifter 24 is equipped with a shift switch 14. The shift switch 14 outputs an upshift signal when the right paddle is pulled, and outputs a downshift signal when the left paddle is pulled.

[0020] FIG. 3 shows another example of the relative indicator shift device 24, which is a button-type device mounted on the steering wheel 27. The button-type relative indicator shift device 24 is provided with a shift switch 14. The shift switch 14 outputs an upshift signal when the right button is pressed, and outputs a downshift signal when the left button is pressed. The button-type relative indicator shift device 24 may be mounted in a location other than the steering wheel. For example, a button mounted on the center console may be used as the relative indicator shift device 24.

[0021] FIG. 4 shows a pseudo shift lever 24 that simulates a shift lever, which is a type of sequential shifter, as yet another example of a relative instruction type shift device 24. The pseudo shift lever 24 is a dummy that is different from an actual shift lever. (a) is an example of the pseudo shift lever 24 mounted on the center console, and (b) is an example of the pseudo shift lever 24 mounted on the steering column. The pseudo shift lever 24 is provided with a shift switch 14. The shift switch 14 outputs an upshift signal when the shift lever is moved toward the rear or upward, and outputs a downshift signal when the shift lever is moved toward the front or downward. The pseudo shift lever 24 may be provided in a location other than the center console or the steering column.

[0022] FIG. 5 shows yet another example of the relative command shift device 24. For example, the relative command shift device 24 may be a toggle switch as shown in (a). When the driver pushes the knob back, the switch outputs an upshift signal, and when the driver pushes the knob forward, the switch outputs a downshift signal. Alternatively, the relative command shift device 24 may be a rotary switch as shown in (b). When the driver turns the knob to the right, the switch outputs an upshift signal, and when the driver turns the knob to the left, the switch outputs a downshift signal. These switches may be located anywhere inside the electric vehicle 100, as long as the driver can operate them from the driver's seat.

[0023] As yet another example, the relative instruction type shift device 24 may be a touch panel type, that is, a screen for selecting an upshift or downshift may be displayed on the touch panel.

[0024] The driver's operation of the relative instruction type shift device 24 as exemplified above is a discrete operation, and the relative instruction type shift device 24 (shift switch 14) outputs a signal indicating an upshift or downshift discretely each time the driver operates the relative instruction type shift device 24.

[0025] Referring again to FIG. 1, the pseudo clutch operating device 25 is a device for reproducing clutch operation in a transmission vehicle. One example of the pseudo clutch operating device 25 is a pseudo clutch pedal that simulates the clutch pedal of a transmission vehicle. The pseudo clutch pedal is a dummy that is different from an actual clutch pedal. The pseudo clutch pedal has a structure that resembles the clutch pedal of a conventional transmission vehicle. For example, the pseudo clutch pedal is equipped with a reaction force mechanism that generates a reaction force when the driver presses it down. The position when no pressure is applied to the pseudo clutch pedal is the start position of the pseudo clutch pedal, and the position when the pseudo clutch pedal is pressed down to the farthest is the end position of the pseudo clutch pedal. The driver can operate the pseudo clutch pedal from the start position to the end position against the reaction force from the reaction force mechanism.

[0026] Alternatively, the pseudo clutch operating device 25 may be a lever-type operating device or a dial-type operating device that is operated by hand. With the lever-type or dial-type operating device provided as the pseudo clutch operating device 25, the driver can operate it from the start position to the end position against a reaction force, and can experience the same operating feel as a clutch pedal provided in a conventional transmission vehicle.

[0027] Pseudo clutch operation device 25 is provided with a clutch sensor 15. Clutch sensor 15 outputs a signal indicating the amount of operation of pseudo clutch operation device 25. The driver operates pseudo clutch operation device 25 continuously, and the signal indicating the amount of operation is continuously sent to control device 101 while electric vehicle 100 is running or stopped. If pseudo clutch operation device 25 is a pseudo clutch pedal, the amount of depression of the pedal is obtained as the amount of operation of pseudo clutch operation device 25. However, because electric vehicle 100 does not have an actual clutch, the amount of operation of pseudo clutch operation device 25, i.e., the clutch opening, is a virtual clutch opening.

[0028] The electric vehicle 100 also includes a human-machine interface (HMI) 20 as an interface with the driver, an in-vehicle speaker 21, and a display device 26. The HMI 20 includes a touch panel display. The HMI 20 displays information on the touch panel display and accepts input from the driver via touch operations on the touch panel display. The in-vehicle speaker 21 provides information to the driver by voice and is also capable of outputting a pseudo engine sound, which will be described later. The display device 26 can display the virtual rotation speed of a virtual engine, which will be described later (hereinafter referred to as virtual engine rotation speed).

[0029] The electric vehicle 100 is equipped with a control device 101. 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 a vehicle speed sensor 11, an accelerator pedal stroke sensor 12, a brake pedal stroke sensor 13, a shift switch 14, and a clutch sensor 15, the electric vehicle 100 is also equipped with various other sensors.

[0030] 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 storing 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 made up of multiple instructions. The processor 102 reads and executes the program 104 and data 105 from the memory 103, and generates control signals based on signals acquired from each sensor. The control device 101 may include one or more processors 102.

[0031] The control device 101 can control the electric vehicle 100 in various control modes. The driver can select a control mode by touching the touch panel display of the HMI 20. More 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. Below, we will explain the control modes of the electric vehicle 100 by the control device 101 that the driver can select by operating the HMI 20.

[0032] 3. Electric vehicle control mode The control modes of the electric vehicle 100 that can be selected by the control device 101 include at least the EV mode and the MT mode. The driver can select the control mode from a selection screen that is displayed on the touch panel display of the HMI 20.

[0033] When the EV mode is selected, the control mode of the electric vehicle 100 switches to the EV mode. The EV mode is a mode in which the electric motor is controlled with normal torque characteristics to drive the vehicle. In the EV mode, the gear shift operation of the relative command type shift device 24 and the clutch operation of the pseudo clutch operation device 25 are disabled. In the EV mode, the driver can basically drive the electric vehicle 100 by operating only the accelerator pedal 22, the brake pedal 23, and the steering wheel 27.

[0034] When the MT mode is selected, the control mode of the electric vehicle 100 switches to the MT mode. The MT mode is a control mode for operating the electric vehicle 100 like a transmission vehicle. In the MT mode, the operation of the relative command type shift device 24 and the pseudo clutch operation device 25 is enabled, and the operation when the gear ratio of a manual transmission is switched is reproduced by the gear shift operation of the relative command type shift device 24.

[0035] The driver may also be able to select options regarding engine characteristics, engine sound, drive mode, suspension characteristics, number of shift positions, etc. By appropriately combining these options, the driver can determine the characteristics of the transmission vehicle that he or she wants electric vehicle 100 to simulate. In this way, by operating the touch panel display of HMI 20, the control mode of electric vehicle 100 can be switched to suit the driver's preferences.

[0036] In addition, the electric vehicle 100 may be provided with a mode changeover switch for switching between the EV mode and the MT mode, and the driver may be able to switch between the EV mode and the MT mode by pressing the mode changeover switch instead of operating the display screen of the touch panel display.

[0037] Such control modes that can be switched by the driver relate to the driving control of the electric vehicle 100. In the next chapter, the driving control of the electric vehicle 100 by the control device 101 will be described.

[0038] 4. Electric vehicle driving control Fig. 6 is a diagram showing the configuration of a control device 101 related to the driving control of an electric vehicle 100. In detail, Fig. 6 shows the configuration related to torque control in particular among driving control. One or more driving control programs 104 stored in a memory 103 are executed by the processor 102, causing the processor 102 to function as a driving control device.

[0039] A control mode signal is input from the HMI 20 to the control device 101, which functions as a driving control device. The control mode signal includes information about the control mode selected by the driver. The control device 101 executes process P110 based on the control mode signal. In process P110, the control mode is switched in accordance with the control mode signal. The control mode switching that particularly affects driving control is the switch between EV mode and MT mode.

[0040] When the control mode is switched to EV mode, the control device 101 executes process P120 for torque calculation in EV mode. In process P120, the control device 101 obtains the vehicle speed from the signal of the vehicle speed sensor 11 and obtains the accelerator opening from the signal of the accelerator pedal stroke sensor 12. The control device 101 has a motor torque map that uses the accelerator opening and vehicle speed as parameters. The control device 101 inputs the vehicle speed and accelerator opening into the motor torque map and controls the inverters 3F, 3R so that the electric motors 4F, 4R generate the torque obtained from the motor torque map.

[0041] When the control mode is switched to MT mode, the control device 101 executes process P130 for calculating torque in MT mode. Process P130 includes process P131 for calculating torque to be generated at the drive wheels. Process P130 also includes process P132 and process P133. Process P132 is for calculating torque to be generated at the front electric motor 4F, and process P133 is for calculating torque to be generated at the rear electric motor 4R. Processes P132 and P133 are executed in accordance with the drive wheel torque calculated in process P130 and the torque distribution between the front wheels 6F and the rear wheels 6R.

[0042] A vehicle model MOD01 is used to calculate the drive wheel torque in 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 called a virtual engine, the clutch virtually realized is called a virtual clutch, and the transmission virtually realized is called a virtual transmission. The engine model MOD11 models the virtual engine. The clutch model MOD12 models the virtual clutch. The transmission model MOD13 models the virtual transmission.

[0043] The engine model MOD11 calculates a virtual engine speed and a 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 a signal from the vehicle speed sensor 11. The accelerator opening is obtained from a signal from the accelerator pedal stroke sensor 12. The overall reduction ratio is a 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 specified for each accelerator opening. Note that the engine characteristics of the engine model MOD11 may be selectable by the driver by operating the HMI 20.

[0044] The clutch model MOD12 calculates a torque transmission gain. The torque transmission gain is a gain used to calculate the degree of torque transmission of the virtual clutch according to the clutch opening. The clutch opening is obtained from the signal of the clutch sensor 15. When the pseudo clutch operating device 25 is a pseudo clutch pedal, the clutch opening is 0% at the start position of the pseudo clutch pedal 25 and 100% at the end position of the pseudo clutch pedal 25. The clutch model MOD12 assigns a torque transmission gain to the clutch opening. The torque transmission gain is converted into the clutch torque capacity of the virtual clutch, i.e., the virtual clutch torque capacity. Then, based on a 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. The clutch model MOD12 also calculates a slip ratio by subtracting the torque transmission gain from 1. The slip ratio is used to calculate the virtual engine speed in the engine model MOD11.

[0045] The transmission model MOD13 calculates a virtual gear ratio. The virtual gear ratio is a gear ratio in the virtual transmission determined by the virtual shift position. A virtual gear ratio is set for each shift position. The maximum virtual gear ratio is set for first gear, and the virtual gear ratios decrease in the order of second gear, third gear, fourth gear, and so on. The shift position is increased by one gear when an upshift signal is received from the shift switch 14, and the shift position is decreased by one gear when a downshift signal is received from the shift switch 14. At this time, the control device 101 accepts input from the shift switch 14 only when the operation amount of the pseudo clutch operating device 25, i.e., the clutch opening, is equal to or greater than a predetermined amount. If the clutch opening is less than the predetermined amount, the input from the shift switch 14 is invalid, and no upshift or downshift is performed even if the relative instruction shift device 24 is operated.

[0046] There is no physical restriction on the number of shift positions indicated by the relative indication type shift device 24. Therefore, the number of shift positions may be variable, and different transmission models MOD13 may be used depending on the number of shift positions.

[0047] The transmission model MOD13 calculates a virtual transmission torque using the virtual gear ratio and the virtual clutch torque. The virtual transmission torque is a virtual torque output from the virtual transmission. The control device 101 controls the inverters 3F, 3R so that the output torque of the electric motors 4F, 4R changes 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 appearance of a vehicle equipped with a stepped transmission.

[0048] The vehicle model MOD01 calculates the drive wheel torque from the virtual transmission torque and the reduction ratio. 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 between the front wheels 6F and the rear wheels 6R can be fixed or can be changed actively or passively. For example, the driver may be able to select a four-wheel drive mode in which all four wheels are driven or a rear-wheel drive mode in which only the rear wheels are driven.

[0049] In process P132, the torque of the front electric motor 4F in the MT mode (front motor torque) is calculated by multiplying the drive wheel torque calculated in process P131 by the torque distribution rate 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 that the front electric motor 4F generates the front motor torque calculated in process P132.

[0050] In process P133, the torque of the rear electric motor 4R in MT mode (rear motor torque) is calculated by multiplying the drive wheel torque calculated in process P131 by the torque distribution rate 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 that the rear electric motor 4R generates the rear motor torque calculated in process P133.

[0051] The vehicle model MOD01 is determined in advance and stored in memory 103. Considering the motor torque of electric motors 4R, 4F calculated in process P130 by vehicle model MOD01, when the clutch opening is 0%, the motor torque is constant relative to the vehicle speed and accelerator opening under a certain virtual shift position. Hereinafter, the motor torque determined by the virtual shift position, vehicle speed, and accelerator opening is referred to as the basic torque of electric motors 4R, 4F. As the clutch opening increases, the motor torque is reduced from the basic torque, and is set to zero when the clutch opening exceeds a predetermined opening. Furthermore, when the virtual shift position is changed, the relationship between the vehicle speed, accelerator opening, and basic torque is changed accordingly.

[0052] 5. Sound control for electric vehicles The control device 101 may also perform sound control to control the sound emitted from the in-vehicle speaker 21. The processor 102 functions as a sound control device by executing one or more sound control programs 104 stored in the memory 103. The processor 102 functioning as the torque control device and the processor 102 functioning as the sound control device may be separate processors or may be the same processor.

[0053] The control device 101 as a sound control device can emit artificially generated sounds from the in-vehicle speaker 21. One of the artificial sounds is a pseudo engine sound that resembles the engine sound of a conventional internal combustion engine vehicle. When a control mode signal indicating that the MT mode has been selected is input from the HMI 20, the control device 101 as a sound control device generates the pseudo engine sound based on the virtual engine torque and virtual engine speed calculated in process P131.

[0054] When the driver can select an engine sound, the engine sound selected by the HMI 20 is used as the sound source of the pseudo engine sound to be generated from the in-vehicle speaker 21. However, the sound of the sound source is not used as is; the sound pressure of the engine sound is calculated so that the greater the virtual engine torque, the greater the sound pressure, and the frequency of the engine sound is calculated so that the greater the virtual engine speed, the higher the frequency. Then, 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, and the pseudo engine sound is reproduced from the in-vehicle speaker 21. The virtual engine torque and virtual engine speed change depending on the driver's accelerator operation, gear shift operation, and clutch operation. In this way, by changing the sound pressure and frequency of the pseudo engine sound in accordance with the virtual engine torque and virtual engine speed that change in accordance with the driver's operation, the driver can be given a sense of realism as if they were driving a vehicle with a real transmission.

[0055] 6. Other forms of pseudo-clutch operating devices Pseudo clutch operating device 25 may be a device for switching the clutch ON / OFF. For example, pseudo clutch operating device 25 may be a switch, and turning the switch ON may turn the clutch OFF (clutch opening 100%), and turning the switch OFF may turn the clutch ON (clutch opening 0%). Alternatively, even if pseudo clutch operating device 25 is a pedal-type operating device operated by the driver's foot, it does not necessarily have to be a device for inputting a continuous amount of operation; the clutch may be turned OFF when the driver depresses the pedal and turned ON when the driver releases the pedal. In this case, the operation input by the driver to pseudo clutch operating device 25 is a discrete operation, and clutch sensor 15 outputs a signal indicating whether the clutch is ON or OFF discretely each time the driver operates the device.

[0056] Furthermore, when pseudo clutch operation device 25 is a device that switches the clutch ON / OFF, the torque transmission gain input to vehicle model MOD12 in Fig. 6 is 1 when the clutch is ON and 0 when the clutch is OFF. Furthermore, control device 101 accepts input from relative command type shift device 24 when the clutch is ON, and invalidates the input when the clutch is OFF.

[0057] 7. Gear shifting using a relative indicator shift device and a pseudo-clutch operation device As described above, the driver of electric vehicle 100 can experience the operation of a transmission vehicle in electric vehicle 100 by operating HMI 20 to switch the control mode to MT mode. In MT mode, which is one of the operations that simulates a transmission vehicle, the driver can manually perform a pseudo gear change operation (shift change) and switch the virtual shift position.

[0058] Gear shifting in electric vehicle 100 is performed by relative command type shift device 24. In addition to shifting gears using relative command type shift device 24, the driver must also manually operate the clutch using pseudo clutch operation device 25. By manually operating the clutch using pseudo clutch operation device 25, the operating feel becomes closer to that of a real transmission vehicle, which is great for drivers who want to enjoy driving a transmission vehicle.

[0059] Furthermore, by providing the pseudo clutch operating device 25, it is possible to use the pseudo clutch operating device 25 for operations other than gear shifting. For example, the driver can create a virtual neutral state by operating the pseudo clutch operating device 25. In this way, it becomes possible to reproduce behavior that is closer to that of a transmission vehicle, increasing the ways in which the driver can enjoy the vehicle.

[0060] The following are some of the benefits of using the relative instruction shift device 24 to perform gear shifting. For comparison, consider a case where the device used for gear shifting is a device that simulates an H-type shifter in a transmission vehicle. With an H-type shifter, the shift position is absolutely specified by the position of the lever. However, since it is not possible to operate the shifter while looking at the shifter's hand while driving, the driver may make a mistake in selecting the wrong shift position. In contrast, with the relative instruction shift device 24, the virtual shift position is changed one gear at a time by the driver's operation. Because the shift position is changed step by step, it is possible to prevent the driver from accidentally selecting a shift position several gears higher or lower. This makes operation easier for the driver.

[0061] Furthermore, it is more effective if the relative command type shift device 24 is provided on the steering wheel 27. The driver holds the steering wheel 27 while driving the electric vehicle 100, but by providing the relative command type shift device 24 on the steering wheel 27, the driver can operate the relative command type shift device 24 without removing one hand from the steering wheel 27. This stabilizes the force that holds the steering wheel, enabling stable driving. Furthermore, since there is no need to remove the hand from the steering wheel 27, gear changes can be performed quickly.

[0062] Furthermore, the relative instruction type shift device 24 mounted on the steering wheel is more effective if it has paddles or buttons for upshifting and paddles or buttons for downshifting, separated on the left and right, as in the example shown in Figure 2 or 3. In this case, it is easier to tell which paddles or buttons correspond to upshifting and which correspond to downshifting without looking at your hands, making it less likely that you will make an incorrect operation.

[0063] 8. Virtual engine speed control A condition for the control device 101 to accept a gear shift operation input to the relative instruction type shift device 24 is that an operation amount equal to or greater than a predetermined amount has been input to the pseudo clutch operation device 25. Other conditions may also be set for the control device 101 to accept a gear shift operation. Here, a case where a condition related to the virtual engine rotation speed is set will be described.

[0064] Specifically, an appropriate range for the virtual engine rotation speed is set in advance. When the driver performs a gear shift operation, the control device 101 predicts the virtual engine rotation speed when the driver accepts the gear shift operation and switches the virtual shift position. If the virtual engine rotation speed after the gear shift is predicted to be outside the appropriate range, the control device 101 does not accept the gear shift operation. The virtual engine rotation speed after the gear shift can be predicted from the current vehicle speed based on the vehicle model MOD01. The upper limit of the appropriate rotation speed range is set to be the lower limit of the rotation speed at which an over-rev state occurs, and the lower limit of the appropriate rotation speed range is set to be the upper limit of the rotation speed at which an under-rev state occurs. Although the electric vehicle 100 does not actually have an engine that can be in an over-rev or under-rev state, the upper and lower limits of the rotation speed are set based on the engine characteristics of the simulated transmission vehicle. If the driver can select engine characteristics through the HMI 20, the upper and lower limits of the rotation speed may be set for each engine characteristic. In this way, by preventing the virtual engine from over-revving or under-revving, the behavior of the electric vehicle 100 can be made even closer to that of a vehicle with a transmission, thereby increasing the driver's satisfaction.

[0065] The control device 101 may also have a function equivalent to the auto-blipping function of a transmission vehicle. That is, when a downshift is performed, the virtual engine speed may be automatically increased in accordance with the vehicle speed. This allows the virtual engine speed to change naturally, making it possible to more closely resemble the behavior of a transmission vehicle.

[0066] 9. Time Chart 9-1. Example of upshifting FIG. 7 is a time chart showing an example of an upshift. Here, an example will be described in which the relative command shift device 24 is a pseudo paddle shifter and the pseudo clutch operating device 25 is a pseudo clutch pedal. However, the same can be said for cases in which the relative command shift device 24 and the pseudo clutch operating device 25 are other devices. Also, here, the clutch opening threshold for accepting input from the relative command shift device 24 is set to 70%. However, the clutch opening threshold is not limited to this value and can be set arbitrarily.

[0067] At time T0, when the time chart starts, the shift position is set to N. At time T1, the driver operates the upshift paddle of the relative instruction shift device 24. However, at this time, no operation amount is input to the pseudo clutch pedal, and the clutch opening is 0%. Therefore, the control device 101 does not accept an upshift instruction from the shift switch 14, and the virtual shift position is not changed.

[0068] At time T2, the driver depresses the pseudo clutch pedal, and the clutch opening becomes 100%. When a clutch opening exceeding the threshold is input, the control device 101 enters a state in which it is able to accept input from the relative instruction type shift device 24. In this state, at time T3, the driver operates the upshift side paddle. This causes the control device 101 to accept the upshift signal input from the shift switch 14, and an upshift is performed.

[0069] The driver then depresses the pseudo clutch pedal again, and at time T4, the upshift paddle of relative command shift device 24 is operated again with the clutch opening at 100%. Because the operation amount input to the pseudo clutch pedal is greater than the threshold, control device 101 receives an upshift signal, and the virtual shift position is increased by one, just as at time T3.

[0070] In the example of Fig. 7, the input of the upshift signal is accepted and the virtual shift position is changed when the switch is pressed, not when the switch is released after being pressed. In this way, by setting the timing for changing the virtual shift position to when the switch is pressed, it is possible to reduce the sense of discomfort felt by the driver and make operation easier.

[0071] 9-2. Example of downshifting Figure 8 is a time chart showing an example of a downshift. As with Figure 7, the example will be described in which the relative command shift device 24 is a pseudo paddle shifter, the pseudo clutch operating device 25 is a pseudo clutch pedal, and the clutch opening threshold for receiving input from the relative command shift device 24 is 70%. The operation during a downshift is basically the same as during an upshift.

[0072] At time T0, when the time chart begins, the shift position is set to N+3. At time T1, the driver operates the downshift paddle of the relative instruction shift device 24. However, at this time, no operation amount is input to the pseudo clutch pedal. Therefore, the control device 101 does not accept a downshift instruction from the shift switch 14, and the virtual shift position is not changed.

[0073] At time T2, the driver depresses the pseudo clutch pedal, and the clutch opening becomes 100%. When a clutch opening exceeding the threshold is input, the control device 101 enters a state in which it is possible to receive input from the relative instruction type shift device 24. In this state, at time T3, the driver operates the downshift side paddle. This causes the control device 101 to receive a downshift signal input from the shift switch 14, and the virtual shift position is shifted down one gear. Note that the virtual engine speed temporarily increases after time T3 because the auto-blipping function is activated. This is the control described in Chapter 8.

[0074] While the driver continues to depress the pseudo clutch pedal, at time T4, the downshift paddle of the relative instruction shift device 24 is operated again. Because the pseudo clutch pedal is being operated by an amount greater than the threshold, the control device 101 accepts a downshift signal and the virtual shift position is shifted down another gear. The auto-blipping function is also activated, and the virtual engine speed temporarily increases after the downshift. Note that a similar change in virtual engine speed occurs when the driver depresses the accelerator pedal 22. In other words, when the accelerator pedal 22 is depressed with the clutch opening at 100%, the virtual engine speed displayed on the display device 26 increases.

[0075] As shown in the example of Figure 8, the control device 101 may permit multiple gear changes while the driver is depressing the pseudo clutch pedal. In other words, if the relative instruction type shift device 24 is operated multiple times while the pseudo clutch pedal is continuously depressed, all of the multiple operations may be accepted and the virtual shift position may be lowered by multiple steps. This eliminates the need for the driver to re-depress the pseudo clutch pedal, allowing for quick gear changes.

[0076] At time T5, the downshift paddle is operated again with the pseudo clutch pedal depressed. At this time, the condition for accepting a gear shift is met with respect to the amount of operation of the pseudo clutch operating device 25. However, the control device 101 does not accept the gear shift operation because the virtual engine rotation speed does not satisfy a predetermined condition. Specifically, the virtual engine rotation speed when the gear shift is accepted exceeds the upper limit of a preset appropriate range, so the gear shift command is not accepted. This is an example of the condition related to the virtual engine rotation speed described in Chapter 8. [Explanation of symbols]

[0077] 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, 11 Vehicle speed sensor, 12 Accelerator pedal stroke sensor, 13 Brake pedal stroke sensor, 14 Shift switch, 15 Clutch sensor, 21 In-car speaker, 22 Accelerator pedal, 23 Brake pedal, 24 Relative indication type shift device, 25 Pseudo clutch operation device, 26 Display device, 27 Steering, 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, a control device for controlling the electric motor; a first indicator that outputs continuous instructions to the control device in accordance with an operation amount; a second indicator that issues a relative instruction to the control device for each operation; a third indicator that issues a continuous or discrete instruction to the control device in accordance with an operation amount; Equipped with The control device switching a relationship between a base torque, which is a torque of the electric motor when the third indicator is not operated, an operation amount of the first indicator, and a vehicle speed of the electric vehicle, from among a plurality of predetermined relationships in accordance with the operation of the second indicator; reducing the torque of the electric motor from the base torque in response to an instruction from a third indicator; and accepting an input from the second indicator only when an operation amount of the third indicator is greater than a predetermined amount. An electric vehicle characterized by:

2. 2. The electric vehicle according to claim 1, The second indicator is provided on the steering wheel of the electric vehicle. An electric vehicle characterized by:

3. 3. The electric vehicle according to claim 2, The second indicator is a pseudo paddle shifter that simulates a paddle shifter of a manual transmission. An electric vehicle characterized by:

4. The electric vehicle according to any one of claims 1 to 3, The electric vehicle further includes a vehicle speed sensor that measures the vehicle speed of the electric vehicle, The control device a storage device that stores appropriate vehicle speed ranges determined for each of the plurality of relationships; When the second indicator and the third indicator are operated, determining whether the vehicle speed is within the appropriate vehicle speed range determined for the relationship between the basic torque after switching, the operation amount of the first indicator, and the vehicle speed; When the vehicle speed is not within the appropriate vehicle speed range determined for the relationship between the basic torque after switching, the operation amount of the first indicator, and the vehicle speed, the operation of the second indicator is not accepted. An electric vehicle characterized by:

5. The electric vehicle according to any one of claims 1 to 3, a display device that displays a virtual engine rotation speed, The control device When the first indicator is operated while the operation amount of the third indicator is at a maximum, the operation amount of the first indicator is associated with the display of the virtual engine rotation speed. An electric vehicle characterized by:

6. The electric vehicle according to any one of claims 1 to 3, The first indicator is an accelerator pedal An electric vehicle characterized by:

7. 7. The electric vehicle according to claim 6, The plurality of predetermined relationships are determined in advance so as to reproduce the relationship between the accelerator pedal operation amount and engine torque for each of a plurality of gear ratios of a transmission vehicle. An electric vehicle characterized by:

8. The electric vehicle according to any one of claims 1 to 3, The control device switching between a first mode in which operation of the second indicator and the third indicator is disabled and a second mode in which operation of the second indicator and the third indicator is enabled in response to a selection by a driver of the electric vehicle; When the first mode is switched to the second mode, a relationship between the basic torque, the operation amount of the first indicator, and the vehicle speed is selected from the plurality of predetermined relationships in accordance with the vehicle speed; configured to further perform An electric vehicle characterized by:

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