Electric automobile

Abstract

The invention relates to an electric automobile. In an electric vehicle provided with an electric motor as a power source for travel, operability can be improved. The invention relates to an electric vehicle having an electric motor as a drive source. An electric vehicle is provided with an acceleration operation device, a control device for controlling an electric motor, and a torque operation device for inputting an operation amount by a driver of the electric vehicle. The control device acquires an operation amount of the torque operation device, and changes the torque of the electric motor in accordance with the operation amount of the torque operation device.

Description

Technical Field

[0001] This disclosure relates to electric vehicles having an electric motor as a drive source. Background Technology

[0002] Patent Document 1 discloses an electric vehicle equipped with a motor as a power source for driving and capable of control based on multiple driving modes. These driving modes include a manual transmission driving mode and an electric driving mode. In manual transmission mode, the motor's drive torque is controlled by the driver's operation of the gear lever and clutch pedal, achieving a driving feel similar to a manual transmission (MT) vehicle. In electric driving mode, the motor's drive torque is controlled by the driver's operation of the accelerator and brake pedals, achieving a driving feel similar to an automatic transmission (AT) vehicle.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2022-036823 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] Consider an electric vehicle equipped with an electric motor as its power source. In electric vehicles, the torque of the electric motor is typically controlled by the driver's operation of the accelerator pedal, thus enabling the vehicle to be driven. Consider further improving the operability of such an electric vehicle.

[0008] One object of this disclosure is to provide a technology that improves operability in an electric vehicle equipped with an electric motor as a power source for driving.

[0009] Methods for solving problems

[0010] The first aspect of this disclosure relates to an electric vehicle having an electric motor as its drive source. The electric vehicle includes an acceleration control device, a control device for controlling the electric motor, and a torque control device for inputting the driver's input. The control device receives the input from the torque control device and changes the torque of the electric motor according to the input from the torque control device.

[0011] The electric vehicle mentioned in the first point above has a torque control device in addition to the acceleration control device. The driver can control the torque of the electric motor not only through the acceleration control device but also through the torque control device. Therefore, compared to driving an electric vehicle solely through the acceleration control device, the ability to make fine adjustments to the electric motor's torque improves the vehicle's maneuverability for the driver.

[0012] The second aspect of this disclosure relates to an electric vehicle with an electric motor as its drive source. The electric vehicle includes an acceleration control device, a simulated gear shifting device, a simulated clutch operating device, and a control device for controlling the electric motor. The control device is configured to switch between a manual shifting mode and an automatic mode. In the manual shifting mode, the relationship between the operation amount of the acceleration control device and the torque of the electric motor is switched based on the operation of the simulated gear shifting device and the simulated clutch operating device. In the automatic mode, the torque of the electric motor is continuously varied based on the operation amount of the acceleration control device without requiring operation of the simulated gear shifting device. When the automatic mode is selected, the control device varies the torque of the electric motor based on the operation amount of the simulated clutch operating device.

[0013] According to the electric vehicle described in the second point above, when the automatic mode is selected, the torque of the electric motor changes based on the amount of operation of the simulated clutch operating component. The driver can control the torque of the electric motor not only through the accelerator but also by operating the simulated clutch operating component. Therefore, compared to driving the electric vehicle solely through the accelerator, fine adjustments to the electric motor torque are possible, improving the vehicle's maneuverability for the driver. Furthermore, the simulated clutch operating component is used in manual transmission mode to switch the relationship between the amount of operation of the accelerator and the torque of the electric motor. By switching the relationship between the amount of operation of the accelerator and the torque of the electric motor, the shifting operation of a manual transmission is simulated. By utilizing the operating component used in this virtual shifting operation as well as the operating component used to adjust the torque of the electric motor together with the accelerator in automatic mode, the operating component can be used effectively without waste, even when multiple modes are provided.

[0014] Invention Effects

[0015] Thus, the electric vehicle according to this disclosure, in addition to the acceleration operating device, also has an operating component for adjusting the torque of the electric motor, thereby enabling fine adjustments to the torque and improving the operability of the electric vehicle. Attached Figure Description

[0016] Figure 1 This is a diagram showing the structure of an electric vehicle according to an embodiment of the present disclosure.

[0017] Figure 2 This is a flowchart illustrating an example of the processing flow in the first embodiment.

[0018] Figure 3 This is a timing diagram used to illustrate the relationship between the operating amount of the torque operating device and the motor torque in the first embodiment.

[0019] Figure 4 This is a flowchart illustrating an example of the processing flow in the second embodiment.

[0020] Figure 5 This is a diagram illustrating an example of torque mapping for the first motor and torque mapping for the second motor.

[0021] Figure 6 This is a timing diagram used to illustrate the relationship between the operating amount of the torque operating device and the motor torque in the second embodiment.

[0022] Figure 7 This is a diagram showing the structure of the control device related to the driving control of an electric vehicle equipped with MT mode.

[0023] Explanation of reference numerals in the attached figures

[0024] 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 Travel Sensor 13 Brake Pedal Travel Sensor 14 Opening Sensor 15 Gear Position Sensor 22 Accelerator Pedal 23 Brake Pedal 24 Torque Control Device 25 Simulated Gear Shifting Component 100 Electric Vehicle 101 Control Device 102 Processor 103 Memory 104 Program 105 Data. Detailed Implementation

[0025] The embodiments of this disclosure will be described with reference to the accompanying drawings.

[0026] 1. Structure of the power system of an electric vehicle

[0027] Figure 1 This is a diagram schematically illustrating the structure of an electric vehicle 100 according to an embodiment of the present disclosure. First, referring to... Figure 1 The structure of the power system of electric vehicle 100 is explained.

[0028] The electric vehicle 100 has two electric motors (M) 4F and 4R at the front and rear as power sources for driving. The electric motors 4F and 4R are, for example, three-phase AC motors. The front electric motor 4F is connected to the front drive shaft 5F that drives the front wheels 6F. The rear electric motor 4R is connected to the rear drive shaft 5R that drives the rear wheels 6R. The front wheels 6F are suspended on a left-right independently controlled electronically operated front suspension 7F. The rear wheels 6R are suspended on a left-right independently controlled electronically operated rear suspension 7R.

[0029] Inverters (INV) 3F and 3R are installed on the front electric motor 4F and the rear electric motor 4R, respectively. The front inverter 3F and the rear inverter 3R are connected to the battery (BATT) 2. The battery 2 stores the electrical energy that drives the electric motors 4F and 4R. That is, the electric vehicle 100 is a battery electric vehicle (BEV) that uses the electrical energy stored in the battery 2 to operate. The inverters 3F and 3R are, for example, voltage-source inverters, and control the torque of the electric motors 4F and 4R through PWM control.

[0030] 2. Structure of the control system of an electric vehicle

[0031] Next, refer to Figure 1 The structure of the control system of electric vehicle 100 is described.

[0032] The electric vehicle 100 is equipped with a vehicle speed sensor 11. At least one of the wheel speed sensors (not shown) respectively located on the left and right front wheels 6F and the left and right rear wheels 6R is used as the vehicle speed sensor 11.

[0033] The electric vehicle 100 includes an accelerator pedal travel sensor 12. The accelerator pedal travel sensor 12 is located on the accelerator pedal 22 and outputs a signal indicating the amount of pressure applied to the accelerator pedal 22, i.e., the accelerator opening degree. It should be noted that the accelerator pedal 22 is a foot-operated pedal-type device, but the device used for acceleration operation can also be a hand-operated device. For example, the electric vehicle 100 may also have a hand-operated lever-type or dial-type accelerator operation device instead of the accelerator pedal 22. Sensors are also provided for these acceleration operation devices, outputting signals indicating the amount of operation, i.e., the accelerator opening degree.

[0034] In addition, the electric vehicle 100 is equipped with a brake pedal travel sensor 13. The brake pedal travel sensor 13 is located on the brake pedal 23 and outputs a signal indicating the amount of pressure applied to the brake pedal 23, i.e., the brake opening degree.

[0035] The accelerator pedal 22 and brake pedal 23 are driving operation components for driving the electric vehicle 100. The driver of the electric vehicle 100 can drive the electric vehicle 100 primarily by operating the accelerator pedal 22, brake pedal 23, and a steering wheel (not shown). In addition to these driving operation components, the electric vehicle 100 also has a torque control device 24.

[0036] The torque operating device 24 is used to control the torque of the electric motors 4F and 4R. In the case that the electric vehicle 100 is an electric vehicle equipped with the MT mode described later, the torque operating device 24 may also be a simulated clutch pedal with a structure similar to the clutch pedal of a manual transmission vehicle (MT vehicle). The simulated clutch pedal, for example, has a reaction force mechanism that generates a reaction force relative to the driver's depressor. The position where no depressor force is applied is the initial position of the simulated clutch pedal, and the position when it is fully depressed is the final position of the simulated clutch pedal. The driver can operate the simulated clutch pedal from the initial position to the final position by overcoming the reaction force from the reaction force mechanism. However, the torque operating device 24 is not limited to such a pedal-type operating device. For example, the torque operating device 24 may also be a hand-operated lever-type operating device or a dial-type operating device.

[0037] An opening sensor 14 is provided in the torque operating device 24, which outputs a signal indicating the opening degree of the torque operating device 24, i.e., the operating amount. The relationship between the operating amount of the torque operating device 24 and the torques of the electric motors 4F and 4R will be explained in detail in the next chapter.

[0038] The electric vehicle 100 is equipped with a human-machine interface (HMI) 20, which serves as an interface with the driver. The HMI 20 has 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 HMI 20 may also include in-vehicle speakers that provide information to the driver with sound.

[0039] The electric vehicle 100 includes a control device 101. Sensors and controlled devices mounted on the electric vehicle 100 are connected to the control device 101 via an in-vehicle network. In addition to the vehicle speed sensor 11, accelerator pedal travel sensor 12, brake pedal travel sensor 13, and brake pedal opening sensor 14, various other sensors are mounted on the electric vehicle 100.

[0040] The control device 101 includes at least a processor (processing circuit) 102 and a memory 103. The memory 103 includes RAM for temporary data storage and ROM for storing a program 104 executable by the processor 102 and various data 105 related to the program. The program 104 consists of multiple instructions. The processor 102 reads the program 104 and data 105 from the memory 103 and executes them, generating control signals based on signals obtained from various sensors. The control device 101 may include one processor 102 and multiple memories 103.

[0041] Control device 101 controls electric vehicle 100. The control of electric vehicle 100 performed by control device 101 includes driving control. In driving control, control device 101 obtains the vehicle speed from the signal of vehicle speed sensor 11 and the accelerator pedal travel sensor 12. Control device 101 has a motor torque map that takes the accelerator pedal travel sensor and vehicle speed as parameters. In driving control, basically, control device 101 inputs the vehicle speed and accelerator pedal travel sensor to the motor torque map and controls inverters 3F and 3R to cause electric motors 4F and 4R to generate the torque obtained from the motor torque map.

[0042] Furthermore, when the driver operates the torque operating device 24, the control device 101 changes the torque of the electric motors 4F and 4R based on the signal from the opening sensor 14. Specifically, the control device 101 changes the relationship between the accelerator opening and the motor torque when the operating amount of the torque operating device 24 is below a predetermined amount and when it is above a predetermined amount. Hereinafter, two embodiments will be described regarding the relationship between the torque operating device 24 and the torque of the electric motors 4F and 4R.

[0043] 3. First Implementation Method

[0044] 3-1. Processing Flow

[0045] Figure 2 This is a flowchart illustrating an example of a processing flow related to the determination of motor torque based on the operating amount of the torque operating device 24 in the first embodiment. Figure 2 The processing is repeatedly executed by the control device 101 (processor 102) at a predetermined control cycle.

[0046] In step S110, the control device 101 determines whether the operating amount of the torque operating device 24 is greater than a first predetermined amount. If the operating amount input to the torque operating device 24 is greater than the first predetermined amount (step S110; Yes), the process proceeds to step S120. On the other hand, if the operating amount input to the torque operating device 24 is less than or equal to the first predetermined amount (step S110; No), the process ends.

[0047] In step S120, the control device 101 maintains the motor torque of the electric motors 4F and 4R at a constant value. That is, the control device 101 controls the inverters 3F and 3R so that, regardless of the change in the accelerator opening, the motor torque is maintained at the moment when the operating amount of the torque operating device 24 is greater than a predetermined amount.

[0048] When the motor torque is maintained, the determination in step S110 is performed again. If the operating amount of the torque operating device 24 continues to be greater than the first predetermined amount, the process proceeds to step S120 again, and the motor torque at the moment when the operating amount of the torque operating device 24 is greater than the first predetermined amount continues to be output. If the operating amount of the torque operating device 24 becomes less than the first predetermined amount, the process ends. Afterwards, the normal motor torque based on the vehicle speed and accelerator opening is output.

[0049] In the first embodiment, the motor torque is maintained constant during periods when the amount of operation of the torque operating device 24 is greater than a predetermined amount, without reflecting changes in the accelerator opening. For example, a driver who wants to keep the electric vehicle 100 running stably may want to maintain a constant motor torque. In such a case, it is easier for the driver to operate the torque operating device 24 in a manner that makes the amount of operation greater than the first operating amount, compared to maintaining a constant torque by finely adjusting the amount of pressure applied to the accelerator pedal 22. Therefore, by maintaining a constant motor torque when the amount of operation of the torque operating device 24 is greater than a predetermined amount, the operability of the electric vehicle 100 can be improved.

[0050] 3-2. Timing Diagram

[0051] Figure 3 This is a timing diagram illustrating the relationship between the operating amount of the torque operating device 24 in the first embodiment and the motor torque. Here, the first predetermined amount is set to 0%. Furthermore, although not shown in the diagram, the gearbox is always in driving gear from the beginning to the end of the timing diagram.

[0052] At time T0, the start of the timing diagram, the torque control device 24 operated by the driver is not performed. The control device 101 calculates the torque based on the vehicle speed and accelerator opening, and controls the inverters 3F and 3R to cause the electric motors 4F and 4R to generate the calculated torque. Here, since the vehicle speed and accelerator opening are kept constant, the motor torque is constant.

[0053] At time T1, the driver increases the pressure on the accelerator pedal (22), increasing the accelerator opening. As the accelerator opening increases, the motor torque calculated based on torque mapping also increases, and the vehicle speed begins to rise.

[0054] At time T2, the driver operates the torque operating device 24. Upon receiving the information that the torque operating device 24 has been operated and the operating amount has become greater than 0, the control device 101 stores the motor torque at the moment when the operating amount becomes greater than 0. That is, it stores the motor torque at time T2.

[0055] During the period from time T2 to T3, the operating quantity continues to be input to the torque operating device 24. During the period of inputting the operating quantity to the torque operating device 24, regardless of the accelerator opening, the control device 101 keeps the torque output from the electric motors 4F and 4R constant. After time T2, the driver further increases the pressure on the accelerator pedal 22, causing the accelerator opening to increase, but the control device 101 controls the inverters 3F and 3R so that the motor torque stored at time T2 continues to be output from the electric motors 4F and 4R.

[0056] At time T3, the operation of the torque operating device 24 by the driver ends, and no operating input is given to the torque operating device 24 after time T3. Since the operating input of the torque operating device 24 becomes less than 0%, the control device 101 calculates the torque based on the vehicle speed and accelerator opening as usual, and controls the inverters 3F and 3R to output the calculated torque from the electric motors 4F and 4R. It should be noted that the control device 101 can also perform filtering to smooth out the torque change, so that the motor torque output at time T3 does not change drastically.

[0057] 4. Second Implementation Method

[0058] 4-1. Processing Flow

[0059] Figure 4 This is a flowchart illustrating an example of a processing flow related to the determination of motor torque based on the operating amount of the torque operating device 24 in the second embodiment. Figure 4 The processing is repeatedly executed by the control device 101 (processor 102) at a predetermined control cycle.

[0060] In step S210, the control device 101 determines whether the operating amount of the torque operating device 24 is greater than a second predetermined amount. The second predetermined amount used for this determination may be the same as or different from the first predetermined amount in the first embodiment. If the operating amount input to the torque operating device 24 is greater than the second predetermined amount (step S210; Yes), the process proceeds to step S220. On the other hand, if the operating amount input to the torque operating device 24 is less than or equal to the second predetermined amount (step S210; No), the process ends.

[0061] In the second embodiment, a motor torque mapping is prepared for situations where the operating amount of the torque operating device 24 exceeds a second predetermined amount. Hereinafter, this motor torque mapping will be referred to as the second motor torque mapping. Furthermore, in comparison with the second motor torque mapping, a normal motor torque mapping that does not consider the operating amount of the torque operating device 24 will be referred to as the first motor torque mapping. The second motor torque mapping is prepared in advance and stored as data 105 in the memory 103.

[0062] In step S220, the control device 101 sets the motor torque mapping used to calculate the motor torque to the second motor torque mapping.

[0063] Figure 5 Examples of first and second motor torque mappings are shown. The left side shows the first motor torque mapping, and the right side shows the second motor torque mapping. In each motor torque mapping, the horizontal axis represents vehicle speed, and the vertical axis represents motor torque, specifying the relationship between vehicle speed and motor torque for each accelerator opening. In the second motor torque mapping, the motor torque for each accelerator opening is specified in such a way that the absolute value of the motor torque is smaller compared to the first motor torque mapping.

[0064] Refer again Figure 4 When the motor torque mapping is set to the second motor torque mapping, the process proceeds to step S230. In step S230, the control device 101 calculates the motor torque based on the second motor torque mapping set in step S220. The motor torque calculated here is a torque whose absolute value is smaller than the torque calculated when using the first motor torque mapping.

[0065] When the motor torque is calculated, the determination in step S210 is performed again. If the operating amount of the torque operating device 24 remains greater than the second predetermined amount, the process proceeds to steps S220 and S230 again to calculate the motor torque based on the second motor torque mapping. If the operating amount of the torque operating device 24 becomes less than the second predetermined amount, the process ends. Afterwards, according to the first motor torque mapping, the normal motor torque based on vehicle speed and accelerator opening is calculated.

[0066] In the second embodiment, when the operating amount of the torque operating device 24 is greater than the second predetermined amount, a second torque mapping, different from the usual first torque mapping, is used to calculate the motor torque. In the second motor torque mapping, the motor torque for each accelerator opening is specified such that the absolute value of the motor torque is smaller than that of the first motor torque mapping. Therefore, compared to the case where the operating amount of the torque operating device 24 is less than the second predetermined amount, the absolute value of the output motor torque becomes smaller.

[0067] By using different motor torque mappings when the operating amount of the torque operating device 24 is greater than the second predetermined amount, it is easier for the driver to fine-tune the motor torque compared to controlling the motor torque solely through the accelerator pedal 22. This improves the operability of the electric vehicle 100.

[0068] It should be noted that, as another example, the output motor torque can also be set to 0 when the operating amount of the torque operating device 24 is greater than or equal to a predetermined amount. This predetermined amount can be the same as or greater than the second predetermined amount. For example, the second predetermined amount can be set to 0%. If the operating amount of the torque operating device 24 is greater than 0%, the motor torque calculated based on the second motor torque mapping is output. If the operating amount of the torque operating device 24 further increases to 100%, the output motor torque is set to 0.

[0069] 4-2. Timing Diagram

[0070] Figure 6 This is a timing diagram illustrating the relationship between the operating amount of the torque operating device 24 and the motor torque in the second embodiment. Here, the second specified amount is set to 0%. Furthermore, although not shown in the diagram, the gearbox is always in driving gear from the beginning to the end of the timing diagram.

[0071] At time T0, the start of the timing diagram, the torque control device 24 operated by the driver is not performed. The control device 101 calculates the motor torque based on the vehicle speed and accelerator opening according to the first motor torque mapping, and controls the inverters 3F and 3R to cause the electric motors 4F and 4R to generate the calculated torque. Here, since the vehicle speed and accelerator opening are kept constant, the motor torque is constant.

[0072] At time T1, the driver increases the pressure on the accelerator pedal 22, increasing the accelerator opening. At this time, since the torque operating device 24 is not activated, the control device 101 calculates the motor torque according to the first motor torque mapping. The calculated torque increases with the increase in accelerator opening.

[0073] During the period from time T2 to time T3, the driver operates the torque control device 24 to input an operation amount. Since the operation amount is greater than 0%, the control device 101 calculates the motor torque according to the second motor torque mapping. As the accelerator opening increases, the motor torque calculated based on the second motor torque mapping also increases. However, the absolute value of the motor torque becomes smaller compared to the absolute value of the motor torque calculated according to the first motor torque mapping.

[0074] When the driver ends the operation of the torque control device 24 at time T3, the motor torque using the first motor torque mapping is calculated again. It should be noted that at times T2 and T3, the control device 101 can also perform filtering to prevent abrupt changes in motor torque.

[0075] At time T4, the driver releases the accelerator pedal 22, reducing the accelerator opening. As the accelerator opening decreases, the torque calculated based on the torque mapping of the first motor also decreases, eventually becoming negative. Additionally, the vehicle speed gradually decreases.

[0076] At time T5, the driver operates the torque control device 24 again. Upon receiving an input quantity greater than 0% to the torque control device 24, the control device 101 switches the motor torque mapping to the second motor torque mapping. The calculated absolute value of the torque is smaller than the absolute value of the torque calculated based on the first motor torque mapping. Because the absolute value of the torque is smaller, the deceleration is smaller compared to the case where the torque control device 24 is not operated.

[0077] At time T6, the driver ends the operation of the torque control device 24. The control device 101 again uses the first motor torque mapping to calculate the motor torque. The absolute value of the calculated torque is greater than the absolute value of the torque calculated according to the second motor torque mapping. Since the output torque becomes negative, the vehicle eventually stops, and the motor torque becomes 0.

[0078] 5. Application Examples

[0079] Electric vehicle 100 can also be a vehicle with a "MT mode" that simulates the driving of a manual transmission (MT) vehicle. The driver can switch between EV mode and MT mode, which is the normal BEV mode, via HMI20. Alternatively, the control mode can be switched automatically, for example, when the battery charge of battery 2 decreases, battery 2 becomes hot, or an abnormality is detected in the powertrain of electric vehicle 100.

[0080] In MT mode, the driver uses the simulated gear shifting operation component 25 and the torque operation device 24 to perform virtual gear shifting operations.

[0081] The simulated transmission operation unit 25 is, for example, a simulated H-type gear shifter that simulates an H-type gear shifter. The simulated H-type gear shifter has a structure similar to a gear lever located on a control panel and can move along an H-shaped shift groove between gears. However, since the electric vehicle 100 does not have a physical transmission, the gears of the simulated H-type gear shifter are virtual. A gear position sensor 15 is provided in the simulated transmission operation unit 25. The gear position sensor 15 outputs a signal indicating the gear selected by the simulated transmission operation unit 25.

[0082] In MT mode, the torque operating device 24 is used as an operating component to simulate clutch operation. Since the torque operating device 24 in MT mode is used to simulate clutch operation, it can also be referred to as a simulated clutch operating component. In MT mode, the operating quantity of the torque operating device 24 obtained by the opening sensor 14 is processed by the control device 101 as the operating quantity of the simulated clutch operating device, i.e., the clutch opening. However, since the electric vehicle 100 does not have a physical clutch, the operating quantity of the simulated clutch operating device is a virtual clutch opening.

[0083] Figure 5 This is a diagram illustrating an example of the structure of a control device 101 associated with the driving control of such an electric vehicle 100. The processor 102 functions as a driving control device by executing one or more driving control programs 104 stored in the memory 103.

[0084] A control mode signal is input from the HMI20 to the control unit 101, which functions as a driving control device. The control mode signal contains information related to the control mode selected by the driver. The control unit 101 executes processing P110 based on the control mode signal. In processing P110, the control mode is switched according to the control mode signal.

[0085] When the control mode is switched to EV mode, the control unit 101 executes processing P120 for torque calculation in EV mode. The method for calculating the motor torque in processing P120 is as described above. The control unit 101 inputs the vehicle speed and accelerator opening into the motor torque mapping, controlling the inverters 3F and 3R to cause the electric motors 4F and 4R to generate the torque obtained from the motor torque mapping. That is, in EV mode, the operation of the simulated gear shifting unit 25 by the driver is not required, and the motor torque is continuously varied based on the accelerator opening. Furthermore, at this time, the control unit 101 varies the motor torque according to the operation amount of the torque operation device 24.

[0086] When the control mode is switched to MT mode, the control device 101 executes a torque calculation process P130 for MT mode. Process P130 includes a process P131 for calculating the torque generated at the drive wheels. Additionally, process P130 includes processes P132 and P133. Process P132 is for calculating the torque generated by the front electric motor 4F, and process P133 is for calculating the torque generated by the rear electric motor 4R. Processes P132 and P133 are executed according to the drive wheel torque calculated in process P130 and the torque distribution between the front wheel 6F and the rear wheel 6R.

[0087] The calculation of drive wheel torque in P131 uses vehicle model MOD01. Vehicle model MOD01 includes engine model MOD11, clutch model MOD12, and transmission model MOD13. The engine, virtually implemented by vehicle model MOD01, is called the virtual engine, the clutch, and the transmission. In engine model MOD11, the virtual engine is modeled. In clutch model MOD12, the virtual clutch is modeled. In transmission model MOD13, the virtual transmission is modeled.

[0088] Engine model MOD11 calculates virtual engine speed and virtual engine torque. Virtual engine speed is calculated based on vehicle speed, combined reduction ratio, and virtual clutch slip ratio. Virtual engine torque is calculated based on virtual engine speed and accelerator opening. Vehicle speed is obtained from the signal from vehicle speed sensor 11. Accelerator opening is obtained from the signal from accelerator pedal travel sensor 12. The combined reduction ratio is obtained by multiplying the reduction ratio determined by the mechanical structure from the virtual transmission to the drive wheels by the gear ratio of the virtual transmission. In engine model MOD11, the relationship between virtual engine speed and virtual engine torque is defined for each accelerator opening. Alternatively, the engine characteristics of engine model MOD11 can be selected by the driver through the operation of HMI20.

[0089] The clutch model MOD12 calculates the torque transmission gain. The torque transmission gain is the gain used to calculate the degree of torque transmission of the virtual clutch corresponding to the clutch opening. The clutch opening is obtained from the signal of the opening sensor 14. In the case where the torque operating device 24 is a simulated clutch pedal simulating the clutch pedal, the clutch opening is 0% at the beginning position and 100% at the end position of the simulated clutch pedal. In the clutch model MOD12, a torque transmission gain is assigned 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. Additionally, 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 to calculate the virtual engine speed in the engine model MOD11.

[0090] The transmission model MOD13 uses virtual gear ratios and virtual clutch torque to calculate virtual transmission torque. Virtual transmission torque is the virtual torque output from the virtual transmission. Control unit 101 controls inverters 3F and 3R so that the output torque of electric motors 4F and 4R varies according to the virtual transmission torque. The virtual transmission torque varies discontinuously with the switching of the virtual gear ratio. This discontinuous variation in virtual transmission torque causes torque surges in the electric vehicle 100, giving it the appearance of a vehicle with a stepped transmission.

[0091] The vehicle model MOD01 calculates the drive wheel torque based on the virtual transmission torque and 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 to the front wheels 6F and rear wheels 6R can be fixed, or it can be actively or passively varied. Alternatively, the torque distribution can be selected by the driver; in the case of selecting a mode that only drives the rear wheels, the drive wheel torque is the sum of the torques acting on the left and right rear wheels 6R.

[0092] In process P132, the torque of the front electric motor 4F in MT mode (front motor torque) is calculated by multiplying the torque distribution rate to the front wheel 6F and the reduction ratio from the output shaft of the front electric motor 4F to the front wheel 6F by the drive wheel torque calculated in process P131. The control device 101 controls the front inverter 3F to make the front electric motor 4F generate the front motor torque calculated in process P132.

[0093] In process P133, the torque of the rear electric motor 4R in MT mode (rear motor torque) is calculated by multiplying the torque distribution ratio to the rear wheel 6R and the reduction ratio from the output shaft of the rear electric motor 4R to the rear wheel 6R by the drive wheel torque calculated in process P131. The control device 101 controls the rear inverter 3R to make the rear electric motor 4R generate the rear motor torque calculated in process P133.

[0094] Thus, in MT mode, the relationship between accelerator opening and motor torque is switched based on the operation of the simulated gear shifting unit 25 and the simulated clutch operating device, reproducing a virtual gear shifting operation. It should be noted that because it involves gear shifting operations performed by the driver, MT mode can also be called manual shifting mode. Furthermore, in contrast to manual shifting mode, EV mode can also be called automatic mode.

[0095] The simulated clutch operating device is used in MT mode as a device for the driver to input the clutch opening, and in EV mode as a torque operating device 24 for controlling the aforementioned torque. By using the same device differently depending on the control mode, the operability of the electric vehicle 100 can be improved, and the device mounted on the vehicle can be used in various situations, making efficient use of the device without waste.

Claims

1. An electric vehicle having an electric motor as a drive source, wherein, The electric vehicle has the following features: Acceleration operation device; Control device, the control device controlling the electric motor; and A torque operating device, wherein the torque operating device is input to the input input of the driver of the electric vehicle. The control device obtains the operating amount of the torque operating device and changes the torque of the electric motor according to the operating amount of the torque operating device.

2. The electric vehicle according to claim 1, wherein, When the operating amount of the torque operating device is below a specified amount or above a specified amount, the control device changes the relationship between the operating amount of the acceleration operating device and the torque of the electric motor.

3. The electric vehicle according to claim 2, wherein, When the operating amount of the torque operating device is below a predetermined amount, the control device determines the torque of the electric motor based on the vehicle speed of the electric vehicle and the operating amount of the acceleration operating device. During periods when the operating amount of the torque operating device is greater than a predetermined amount, the control device maintains the torque of the electric motor at a constant value.

4. The electric vehicle according to claim 2, wherein, The control device includes a storage device that stores a first motor torque map used when the operating amount of the torque operating device is below a predetermined amount, and a second motor torque map used when the operating amount of the torque operating device is greater than the predetermined amount. The absolute value of the torque specified by the second motor torque mapping is smaller than the absolute value of the torque specified by the first motor torque mapping.

5. An electric vehicle having an electric motor as a drive source, wherein, The electric vehicle has the following features: Acceleration operation device; Simulated speed change operation components; Simulated clutch operating components; and Control device, the control device controls the electric motor, The control device is configured to switch between a manual transmission mode and an automatic mode. In the manual transmission mode, the relationship between the operation amount of the acceleration operation device and the torque of the electric motor is switched according to the operation of the simulated transmission operation component and the simulated clutch operation component. In the automatic mode, the torque of the electric motor is continuously changed based on the operation amount of the acceleration operation device without the operation of the simulated transmission operation component. When the automatic mode is selected, The control device changes the torque of the electric motor according to the amount of operation of the simulated clutch operating component.

6. The electric vehicle according to claim 5, wherein, When the automatic mode is selected, the control device changes the relationship between the operation amount of the simulated clutch operating component and the torque of the electric motor, whether the operation amount is below a predetermined amount or above a predetermined amount.

7. The electric vehicle according to claim 6, wherein, When the automatic mode is selected, When the operating amount of the simulated clutch operating component is below a predetermined amount, the control device determines the torque of the electric motor based on the vehicle speed of the electric vehicle and the operating amount of the acceleration operating device. During periods when the operating amount of the simulated clutch operating component is greater than a predetermined amount, the control device maintains the torque of the electric motor at a constant level.

8. The electric vehicle according to claim 6, wherein, When the automatic mode is selected, When the operating amount of the simulated clutch operating component is below a predetermined amount, the control device calculates the torque of the electric motor based on a first motor torque mapping. When the operating amount of the simulated clutch operating component is greater than a predetermined amount, the control device calculates the torque of the electric motor based on the second motor torque mapping. The absolute value of the torque specified by the second motor torque mapping is smaller than the absolute value of the torque specified by the first motor torque mapping.

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