Electric automobile

Abstract

The invention provides an electric vehicle. An electric vehicle has a motor as a drive source. An electric vehicle includes: an accelerator pedal; a simulated shifter obtained by simulating a shifter used for a shift operation of the manual shift internal combustion engine vehicle; and a control device that changes the relationship among the vehicle speed of the electric vehicle, the accelerator pedal opening degree of the accelerator pedal, and the torque of the motor by receiving the operation of the analog shifter. The control device includes: a memory in which a vehicle model obtained by modeling a virtual vehicle is stored; and a processing circuit coupled with the memory to execute the vehicle model. The vehicle model includes: an engine model obtained by modeling a virtual internal combustion engine; a clutch model obtained by modeling the virtual clutch; a transmission model obtained by modeling a virtual manual transmission; and a driver model.

Description

Technical Field

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

[0002] An electric vehicle is disclosed in Japanese Unexamined Patent Application Publication No. 2022-030838, which can simulate the manual shifting operation of a vehicle equipped with a manual transmission having an internal combustion engine as a power source (hereinafter referred to as a manual transmission internal combustion engine vehicle) by controlling an electric motor. The electric vehicle disclosed in this publication includes a vehicle model obtained by simulating a manual transmission internal combustion engine vehicle and a driver model obtained by simulating a demonstration driver. The vehicle model includes an engine model, a clutch model, and a manual transmission model. The driver model calculates the clutch pedal depression amount of a virtual clutch simulated by the clutch model based on the rotational speed difference between the rotational speed of the input shaft of the virtual manual transmission simulated by the manual transmission model and the rotational speed of the virtual engine simulated by the engine model.

[0003] In the electric vehicle disclosed in the above publication, the driver can perform a shifting operation while depressing the accelerator pedal. However, since the virtual clutch is released in response to the shifting operation, the rotational speed of the virtual engine rises sharply. When a simulated tachometer that displays the rotational speed of the virtual engine is provided, for example, on the instrument panel of the vehicle, the driver feels uncomfortable with the sharp rise in the rotational speed of the virtual engine displayed on the simulated tachometer.

[0004] In addition, in the electric vehicle disclosed in the above publication, the virtual clutch is not engaged unless the rotational speed difference calculated by the driver model is reduced. Therefore, when the driver performs a shifting operation while depressing the accelerator pedal, the shifting operation is not completed due to the increase in the rotational speed difference caused by the rise in the rotational speed of the virtual engine. During this period, since the driving condition in the state where the clutch is released in a manual transmission internal combustion engine vehicle is simulated in the electric vehicle, the longer the time until the shifting operation is completed, the more uncomfortable the driver feels. Summary of the Invention

[0005] The present disclosure provides an electric vehicle that can simulate the shifting operation of a manual transmission internal combustion engine vehicle and complete the shifting without making the driver feel uncomfortable even when the driver performs a shifting operation while depressing the accelerator pedal.

[0006] An electric vehicle according to an embodiment of the present disclosure has an electric motor as a drive source, and includes: an accelerator pedal; a simulated shifter obtained by simulating a shifter used for a shifting operation of a manual transmission type internal combustion engine vehicle; and a control device that receives an operation of the simulated shifter and changes the relationship between the vehicle speed of the electric vehicle, the accelerator pedal opening of the accelerator pedal, and the torque of the electric motor. The control device includes: a memory that stores a vehicle model obtained by modeling a virtual vehicle; and a processing circuit that executes the vehicle model in combination with the memory.

[0007] The vehicle model includes: an engine model obtained by modeling a virtual internal combustion engine; a clutch model obtained by modeling a virtual clutch; a transmission model obtained by modeling a virtual manual transmission; and a driver model obtained by modeling a standard driver. The driver model is a model that calculates the virtual accelerator pedal opening of the virtual internal combustion engine, the virtual clutch opening of the virtual clutch, and the virtual gear range of the virtual manual transmission based on the accelerator pedal opening of the accelerator pedal, the gear position of the simulated shifter, the vehicle speed of the electric vehicle, and the virtual engine speed of the virtual internal combustion engine.

[0008] The driver model is configured to change the virtual accelerator pedal opening from the required opening to the fully closed opening in response to a change in the gear position generated by an operation of the simulated shifter. The required opening refers to the accelerator pedal opening required by the driver through an operation of the accelerator pedal. The driver model is configured to change the virtual clutch opening from the engaged opening to the released opening in response to the completion of the change of the virtual accelerator pedal opening to the fully closed opening. The driver model is configured to change the virtual gear range to the required gear range corresponding to the changed gear position in response to the completion of the change of the virtual clutch opening to the released opening. The driver model is configured to change the virtual clutch opening from the released opening to the engaged opening in response to the convergence of the rotational speed difference between the virtual engine speed and the virtual input shaft speed of the virtual manual transmission within a predetermined range after the virtual gear range is changed to the required gear range. Further, the driver model is configured to change the virtual accelerator pedal opening from the fully closed opening to the required opening in response to the completion of the change of the virtual clutch opening to the engaged opening.

[0009] The driver model may also be configured to temporarily increase the virtual accelerator pedal opening from the fully closed opening in response to the completion of the change of the virtual gear range to the required gear range when the operation of the simulated shifter is a downshift operation. The driver model may also be configured to change the virtual clutch opening from the released opening to the engaged opening in response to the convergence of the rotational speed difference between the virtual engine speed and the virtual input shaft speed of the virtual manual transmission within a predetermined range.

[0010] An electric vehicle according to an embodiment of the present disclosure accepts a change in gear based on the operation of an analog shifter, causing the virtual accelerator pedal opening of a virtual internal combustion engine to change from a required opening to a fully closed opening. Therefore, the virtual engine speed does not increase according to the operation of the driver's accelerator pedal, and the rotational speed difference between the virtual engine speed and the virtual input shaft speed of the virtual manual transmission quickly converges within a predetermined range. Thus, even when a gearshift operation is performed while the driver is stepping on the accelerator pedal, the gearshift can be completed without causing discomfort to the driver. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, in which like reference numerals represent like components.

[0012] Figure 1 is a diagram showing the structure of an electric vehicle according to an embodiment of the present invention.

[0013] Figure 2 is a diagram showing the structure of a vehicle model included in a control device.

[0014] Figure 3 is a diagram for explaining state determination processing based on a driver model.

[0015] Figure 4 is a diagram for explaining in detail gearshift state determination processing based on a driver model.

[0016] Figure 5 is a diagram showing a specific example of gearshift control during upshifting based on a control device.

[0017] Figure 6 is a diagram showing a specific example of gearshift control during downshifting based on a control device.

[0018] Figure 7 is a diagram showing another specific example of gearshift control during downshifting based on a control device. DETAILED DESCRIPTION

[0019] 1. Structure of the powertrain of an electric vehicle

[0020] Figure 1 is a diagram schematically showing the structure of an electric vehicle 100 according to an embodiment of the present disclosure. First, reference is made to Figure 1 to describe the structure of the powertrain of the electric vehicle 100.

[0021] The electric vehicle 100 is equipped with 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 by the left and right independent electronically controlled front suspensions 7F. The rear wheels 6R are suspended by the left and right independent electronically controlled rear suspensions 7R.

[0022] An inverter (INV) 3F and 3R are respectively installed on the front electric motor 4F and the rear electric motor 4R. The front inverter 3F and the rear inverter 3R are respectively connected to the battery (BATT) 2. That is, the electric vehicle 100 is a battery electric vehicle (BEV) that runs using the electric energy stored in the battery 2. The inverters 3F and 3R are, for example, voltage source inverters, and control the torque of the electric motors 4F and 4R through PWM control.

[0023] 2. Structure of the control system of the electric vehicle

[0024] Next, refer to Figure 1 to explain the structure of the control system of the electric vehicle 100.

[0025] The electric vehicle 100 is equipped with a vehicle speed sensor 11. At least one of the unillustrated wheel speed sensors respectively provided on the left and right front wheels 6F and the left and right rear wheels 6R is used as the vehicle speed sensor 11. In addition, the electric vehicle 100 is equipped with an accelerator pedal stroke sensor 12. The accelerator pedal stroke sensor 12 is provided on the accelerator pedal 22 and outputs a signal indicating the depression amount of the accelerator pedal 22, that is, the accelerator pedal opening. And, the electric vehicle 100 is equipped with a brake pedal stroke sensor 13. The brake pedal stroke sensor 13 is provided on the brake pedal 23 and outputs a signal indicating the depression amount of the brake pedal 23, that is, the brake opening.

[0026] The accelerator pedal 22 and the brake pedal 23 are driving operation components for driving the electric vehicle 100. In addition to these driving operation components, the electric vehicle 100 is further equipped with a simulated shifter 24 that simulates the shifting operation of a manual transmission internal combustion engine vehicle. The simulated shifter 24 can be a simulated sequential shifter obtained by simulating a paddle shifter, or a simulated H-type shifter obtained by simulating an H-type shifter. Here, it is assumed that the simulated shifter 24 is a simulated sequential shifter obtained by simulating a paddle shifter.

[0027] The simulated shifter 24 has a structure similar to the shift paddles installed on the steering wheel or the steering shaft, and can move the left and right paddles independently. A gear position sensor 14 is provided on the simulated shifter 24. The gear position sensor 14 outputs an upshift signal when the right paddle is pulled, and outputs a downshift signal when the left paddle is pulled.

[0028] In addition, the electric vehicle 100 includes a human-machine interface (HMI) 20 as an interface with the driver and an analog tachometer 21. The HMI 20 includes a touch panel display. The HMI 20 displays information on the touch panel display and accepts input from the driver based on a touch operation on the touch panel display. The analog tachometer 21 displays the virtual engine speed described later to the driver.

[0029] The electric vehicle 100 includes a control device 101. Sensors mounted on the electric vehicle 100 and devices to be controlled 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, and a gear position sensor 14, various sensors are also mounted on the electric vehicle 100.

[0030] The control device 101 is typically an electronic control unit (ECU). The control device 101 can also be a combination of multiple ECUs. The control device 101 includes at least a processing circuit 102 and a memory 103. The processing circuit 102 can be, for example, a CPU, or a combination of a CPU and an FPGA. The memory 103 includes a RAM for temporarily recording data and a ROM for storing a program 104 executable by the processing circuit 102 and various data 105 associated with the program. The memory 103 can also be built into the processing circuit 102. The program 104 is composed of multiple instruction codes. The processing circuit 102 reads out the program 104 and data 105 from the memory 103 and executes them, and generates a control signal based on signals obtained from each sensor. The number of processing circuits 102 included in the control device 101 can be one or multiple.

[0031] 3. Functions of the Control Device

[0032] 3-1. Control Modes

[0033] The control device 101 can control the electric vehicle 100 in various control modes. The control modes can be selected by the driver himself / herself by performing a touch operation on the touch panel display of the HMI 20. Specifically, by performing a touch operation on the touch panel display of the HMI 20, one or more programs 104 associated with each touch operation are read out from the memory 103 and executed by the processing circuit 102.

[0034] The control modes that can be selected by the HMI 20 include an automatic mode and a manual mode. The automatic mode is a control mode for operating the electric vehicle 100 as a normal BEV. In the automatic mode, the driver can basically drive the electric vehicle 100 only by operating the accelerator pedal 22, the brake pedal 23, and the steering wheel (not shown). In the automatic mode, the shift operation of the analog shifter 24 is invalidated. The manual mode is a control mode for operating the electric vehicle 100 to act like a manually shifted internal combustion engine vehicle. In the manual mode, the operation of the analog shifter 24 is used to reproduce the actions when the gear ratio of the manual transmission is switched.

[0035] 3-2. Vehicle Model

[0036] By executing one or more torque control programs 104 stored in the memory 103 by the processing circuit 102, the control device 101 functions as a torque control device. A control mode signal is input from the HMI 20 to the control device 101 that serves as a torque control device. The control mode signal contains information related to the control mode selected by the driver. When the control mode is switched to the manual mode, the control device 101 uses the vehicle model to calculate the driving wheel torque generated by the driving wheels, and generates a motor torque command value to be provided to the inverters 3F and 3R based on the driving wheel torque.

[0037] Figure 2 It is a diagram showing the structure of the vehicle model MOD01 included in the control device 101. The vehicle model MOD01 is composed of a driver model MOD10, an engine model MOD11, a clutch model MOD12, a manual transmission model MOD13, and an axle-driving wheel model MOD14. The internal combustion engine virtually realized by the vehicle model MOD01 is called a virtual internal combustion engine. The clutch virtually realized by the vehicle model MOD01 is called a virtual clutch. The manual transmission virtually realized by the vehicle model MOD01 is called a virtual manual transmission. Moreover, the manually shifted internal combustion engine vehicle virtually realized by their combination is called a virtual vehicle.

[0038] In the engine model MOD11, a virtual internal combustion engine is modeled. In the clutch model MOD12, a virtual clutch is modeled. In the manual transmission model MOD13, a virtual manual transmission is modeled. In the axle-drive wheel model MOD14, a virtual torque transmission system from the axle to the drive wheels is modeled. Also, in the driver model MOD10, a standard driver is modeled. The standard driver refers to a skilled driver who is accustomed to driving a manually shifted internal combustion engine vehicle. The driver model MOD10 can also be said to be the result of modeling a virtual powertrain control unit (PCU) that comprehensively controls the virtual internal combustion engine, virtual clutch, and virtual manual transmission. Input and output of calculation results are performed between the respective models.

[0039] The engine model MOD11 calculates the virtual engine speed. The virtual engine speed is calculated by different calculation methods in the engaged state and released state of the virtual clutch. In the engaged state of the virtual clutch, the virtual engine speed is calculated based on the vehicle speed, virtual overall reduction ratio, and virtual clutch slip ratio. The vehicle speed is obtained from the signal of the vehicle speed sensor 11. The virtual overall reduction ratio is a value obtained by multiplying the virtual gear ratio of the virtual manual transmission by the virtual reduction ratio determined by the mechanical structure from the virtual manual transmission to the drive wheels. In the released state of the virtual clutch, the virtual engine speed is calculated using the virtual accelerator pedal opening and the virtual moment of inertia of the virtual internal combustion engine. For example, the virtual engine torque can also be calculated based on the current virtual engine speed and the current virtual accelerator pedal opening, and the change amount of the virtual engine speed after a unit time can be calculated based on the virtual engine torque and the virtual moment of inertia.

[0040] In addition, the engine model MOD11 calculates the virtual engine torque. The virtual engine torque is calculated using Figure 2 a mapping as shown in the coordinate diagram, based on the virtual engine speed and the virtual accelerator pedal opening. The virtual accelerator pedal opening is calculated by the driver model MOD10. In the engine model MOD11, the relationship between the virtual engine speed and the virtual engine torque is specified for each virtual accelerator pedal opening. The virtual engine torque is input from the engine model MOD11 to the clutch model MOD12.

[0041] The clutch model MOD12 calculates the virtual torque transfer gain. The virtual torque transfer gain is a gain used to calculate the torque transfer degree of the virtual clutch. The virtual torque transfer gain uses Figure 2The mapping shown in the middle coordinate diagram is calculated based on the virtual clutch opening. The virtual clutch opening is calculated by the driver model MOD10. When the virtual clutch is engaged, the clutch model MOD12 uses the virtual torque transfer gain to calculate the virtual clutch torque. The virtual clutch torque is input from the clutch model MOD12 to the manual transmission model MOD13.

[0042] The manual transmission model MOD13 calculates the virtual gear ratio. The virtual gear ratio is the gear ratio determined by the virtual gear range in the virtual manual transmission. The virtual gear ratio uses Figure 2 The mapping as shown in the middle coordinate diagram is calculated based on the virtual gear range. The virtual gear range is calculated by the driver model MOD10. The manual transmission model MOD13 uses the virtual gear ratio and the virtual clutch torque to calculate the virtual transmission torque. The virtual transmission torque is input from the manual transmission model MOD13 to the axle-drive wheel model MOD14.

[0043] The axle-drive wheel model MOD14 calculates the drive wheel torque. The drive wheel torque is calculated using the virtual transmission torque and the virtual reduction ratio from the virtual manual transmission to the drive wheels. The drive wheel torque becomes the sum of the torques acting on the left and right front wheels 6F and the left and right rear wheels 6R. The torque generated by the front motor 4F is calculated by multiplying the drive wheel torque by the torque distribution ratio to the front wheels 6F and the reduction ratio from the output shaft of the front motor 4F to the front wheels 6F. In addition, the torque generated by the rear motor 4R is calculated by multiplying the drive wheel torque by the torque distribution ratio to the rear wheels 6R and the reduction ratio from the output shaft of the rear motor 4R to the rear wheels 6R.

[0044] The driver model MOD10 calculates the virtual accelerator pedal opening of the virtual internal combustion engine, the virtual clutch opening of the virtual clutch, and the virtual gear range of the virtual manual transmission. To calculate these virtual operation amounts, the driver model MOD10 executes the state determination process P10, the virtual accelerator pedal opening calculation process P21, the virtual clutch opening calculation process P22, and the virtual gear range calculation process P23.

[0045] In the state determination process P10, the vehicle state and the shift state of the virtual vehicle are determined. The content of the state determination process P10 will be described in detail later. The shift state determined in the state determination process P10 is used in the virtual accelerator pedal opening calculation process P21, the virtual clutch opening calculation process P22, and the virtual gear range calculation process P23.

[0046] In the virtual accelerator pedal opening calculation process P21, the virtual accelerator pedal opening is calculated based on the accelerator pedal opening obtained from the accelerator pedal stroke sensor 12 and the shift state of the virtual vehicle determined in the state determination process P10. The accelerator pedal opening obtained from the accelerator pedal stroke sensor 12 represents the magnitude of the torque demand for the motors 4F and 4R. On the other hand, the virtual accelerator pedal opening represents the magnitude of the torque demand of the virtual vehicle for the virtual internal combustion engine. The virtual accelerator pedal opening calculation process P21 can also be said to be a process of correcting the accelerator pedal opening obtained from the accelerator pedal stroke sensor 12 for the virtual internal combustion engine. The virtual accelerator pedal opening calculated in the virtual accelerator pedal opening calculation process P21 is input to the engine model MOD11.

[0047] In the virtual clutch opening calculation process P22, the virtual clutch opening is calculated based on the shift state of the virtual vehicle determined in the state determination process P10. The virtual clutch opening is basically set to 0%. That is, the basic state of the virtual clutch is the engaged state. When a upshift signal or a downshift signal is input from the gear position sensor 14, the virtual clutch opening is temporarily 100%. This means that when the shift operation of the simulated shifter 24 is performed, the virtual clutch is temporarily released. The virtual clutch opening calculated in the virtual clutch opening calculation process P22 is input to the clutch model MOD12.

[0048] In the virtual gear range calculation process P23, the virtual gear range is calculated based on the gear position obtained from the gear position sensor 14 and the shift state of the virtual vehicle determined in the state determination process P10. The number of gears in the virtual gear range becomes the number of gears of the simulated shifter 24 plus the neutral gear. The virtual gear range calculated in the virtual gear range calculation process P23 is input to the manual transmission model MOD13.

[0049] Figure 3 It is a diagram illustrating the state determination process P10. The state determination process P10 includes a vehicle state determination process P11 and a shift state determination process P12. The main process in these two processes P11 and P12 is the vehicle state determination process P11. The shift state determination process P12 is executed when the specified conditions are satisfied in the vehicle state determination process P11.

[0050] In the vehicle state determination process P11, steps S11, S12, and S13 are executed. In step S11, it is determined whether there is a shift request from the driver. When an upshift signal or a downshift signal is input from the gear position sensor 14, it is determined that the driver requests a shift. When accepting a shift request from the driver and starting to shift, the shift-in-progress flag indicating that the virtual vehicle is in the process of shifting is switched from OFF to ON.

[0051] When it is determined that there is a gearshift request from the driver, it is determined in step S12 that the virtual vehicle is in a gearshift state. When it is determined that there is no gearshift request from the driver, it is determined in step S13 that the virtual vehicle is in a state other than the gearshift state. A state other than the gearshift state includes, for example, a state in which the simulated shifter 24 is not operated. When it is determined that the virtual vehicle is in the gearshift state, the gearshift state determination process P12 is executed.

[0052] In the gearshift state determination process P12, it is determined which gearshift state the virtual vehicle is in. The gearshift states include six states from gearshift state M1 to gearshift state M6. In addition, the transition conditions between these gearshift states include seven conditions, namely, transition conditions E1 to E7. M1 - M6 are referred to as gearshift state IDs, and E1 - E7 are referred to as transition condition IDs.

[0053] In gearshift state M1, the virtual accelerator pedal opening changes from the driver's required accelerator pedal opening to zero. The driver's required accelerator pedal opening refers to the accelerator pedal opening obtained by the accelerator pedal stroke sensor 12. The transition condition E1 from gearshift state M1 to gearshift state M2 is that the virtual accelerator pedal opening becomes zero. In gearshift state M2, the virtual clutch is released. That is, the virtual clutch opening becomes 100%. The transition condition E2 from gearshift state M2 to gearshift state M3 is the completion of the release of the virtual clutch. In gearshift state M3, the virtual gear range is changed to the virtual gear range corresponding to the gear after the shift operation. The change of the virtual gear range is via neutral.

[0054] When the change of the virtual gear range is an upshift, it directly changes from gearshift state M3 to gearshift state M5. The transition condition E4 from gearshift state M3 to gearshift state M5 is that the rotational speed difference between the virtual engine speed and the virtual input shaft speed converges within a specified range. On the other hand, when the change of the virtual gear range is a downshift, it changes from gearshift state M3 to gearshift state M5 via gearshift state M4. The transition condition E3 from gearshift state M3 to gearshift state M4 is the completion of the shift to the changed virtual gear range. In gearshift state M4, a process of synchronizing the virtual engine speed with the virtual input shaft speed of the virtual manual transmission is performed. The transition condition E5 from gearshift state M4 to gearshift state M5 is that the rotational speed difference between the virtual engine speed and the virtual input shaft speed converges within a specified range. However, by changing the setting of the manual mode based on the operation of the HMI20, even when the change of the virtual gear range is a downshift, it is possible to directly change from gearshift state M3 to gearshift state M5.

[0055] In the shifting state M5, the virtual clutch is engaged. That is, the virtual clutch opening becomes 0%. The transition condition E6 from the shifting state M5 to the shifting state M6 is that the engagement of the virtual clutch is completed. In the shifting state M6, the virtual accelerator pedal opening returns to the accelerator pedal opening required by the driver, that is, the accelerator pedal opening obtained by the accelerator pedal stroke sensor 12. The transition condition E7 from the shifting state M6 to the shifting state M1 is that the virtual accelerator pedal opening is opened to the accelerator pedal opening required by the driver.

[0056] Figure 4 This is a diagram showing the details of the shifting state determination process P12 for each shifting state ID. Each shifting state from the shifting state M1 to the shifting state M6 can be represented by the virtual accelerator pedal opening, the virtual clutch opening, and the virtual gear range.

[0057] In the shifting state M1, the virtual accelerator pedal opening changes from the opening required by the driver (user required opening) as a user to the fully closed opening, that is, the opening corresponding to the fully closed state, i.e., 0%, at a specified change speed. The virtual clutch opening is set to the engaged opening, that is, the opening relative to the engaged state. The virtual gear range is maintained at the current gear range.

[0058] In the shifting state M2, the virtual accelerator pedal opening is 0%. The virtual clutch opening changes from the engaged opening to the released opening, that is, the opening corresponding to the released state, at a specified change speed. The virtual gear range is maintained at the current gear range.

[0059] In the shifting state M3, the virtual accelerator pedal opening is 0%. The virtual clutch opening is the released opening. The virtual gear range is temporarily changed from the current gear range to the neutral gear and then changed to the gear range required by the driver.

[0060] In the shifting state M4, fuel replenishment is performed to temporarily increase the virtual accelerator pedal opening and raise the virtual engine speed. The virtual clutch opening is the released opening. The virtual gear range becomes the required gear range.

[0061] In the shifting state M5, the virtual accelerator pedal opening is 0%. The virtual clutch opening changes from the released opening to the engaged opening at a specified change speed. The virtual gear range becomes the required gear range.

[0062] In the shifting state M6, the virtual accelerator pedal opening changes from 0% to the user required opening at a specified change speed. The virtual clutch opening becomes the engaged opening. The virtual gear range becomes the required gear range. And, when the virtual accelerator pedal opening returns to the accelerator pedal opening required by the driver, the flag indicating that the virtual vehicle is in the middle of shifting is switched from ON to OFF.

[0063] As described above, the virtual accelerator pedal opening calculation process P21 is executed according to the states of the virtual accelerator pedal opening defined by the respective shift states M1 - M6. In addition, the virtual clutch opening calculation process P22 is executed according to the states of the virtual clutch opening defined by the respective shift states M1 - M6. Then, the virtual gear range calculation process P23 is executed according to the states of the virtual gear range defined by the respective shift states M1 to M6.

[0064] 4. Specific Example of Shift Control

[0065] 4 - 1. Shift Control during Upshift

[0066] Use Figure 5 A specific example of the shift control during upshift executed by the control device 101 will be described. In Figure 5 the timing chart shown, together with the shift state ID and the transition condition ID, the time - dependent changes of the upshift signal, virtual accelerator pedal opening, virtual clutch opening, virtual gear range, virtual engine speed, the drive wheel torque required for the motors 4F, 4R, and the longitudinal acceleration generated by the electric vehicle 100 are depicted.

[0067] According to Figure 5 the timing chart shown, at time t11, an upshift signal is input from the gear position sensor 14 to the control device 101. Upon receiving the input of the upshift signal, the virtual accelerator pedal opening changes from the user - required opening to 0% at a specified change rate. During this period, the virtual clutch opening is maintained at the engaged opening, and the virtual gear range is maintained at the current N - range. By calculating the virtual accelerator pedal opening, virtual clutch opening, and virtual gear range in this way, the rise of the virtual engine speed can be suppressed, and the required drive wheel torque decreases to zero.

[0068] At time t12, the change of the virtual accelerator pedal opening to 0% is completed. In response to this, the virtual clutch opening changes from the engaged opening to the released opening at a specified change rate. During this period, the virtual accelerator pedal opening is maintained at 0%, and the virtual gear range is maintained at the current N - range. By calculating the virtual accelerator pedal opening, virtual clutch opening, and virtual gear range in this way, the virtual engine speed decreases, and the required drive wheel torque is maintained at zero. Also, as the drive wheel torque decreases to zero, the acceleration generated by the vehicle (the longitudinal acceleration of the vehicle) decreases.

[0069] At time t13, the change of the virtual clutch opening to the released opening is completed. In response to this, the virtual gear range is switched from the current N - range to the neutral range. Then, at time t14, which is after a set time from the switch to the neutral range, the virtual gear range is switched to the driver - required gear range (in Figure 5In the example shown, it is in the N+1 gear range). During this period, the virtual accelerator pedal opening is maintained at 0%, and the virtual clutch opening is maintained at the release opening. By calculating the virtual accelerator pedal opening, the virtual clutch opening, and the virtual gear range in this way, the virtual engine speed continuously decreases, and the required drive wheel torque is maintained at zero. Then, the acceleration decreases to zero.

[0070] At time t15, the speed difference between the virtual engine speed and the virtual input shaft speed (in the Figure 5 example shown, it is the N+1 gear speed) converges to the allowable speed difference. In response to this, the virtual clutch opening changes from the release opening to the engagement opening at a specified change speed. During this period, the virtual accelerator pedal opening is maintained at 0%, and the virtual gear range is fixed to the required gear range. By calculating the virtual accelerator pedal opening, the virtual clutch opening, and the virtual gear range in this way, the virtual engine speed further decreases, and the required drive wheel torque is maintained at zero. Also, since the drive wheel torque is continuously maintained at zero, the acceleration is also maintained at zero.

[0071] At time t16, the change of the virtual clutch opening to the engagement opening is completed. In response to this, the virtual accelerator pedal opening changes from 0% to the user-requested opening at a specified change speed. During this period, the virtual clutch opening is fixed to the engagement opening, and the virtual gear range is fixed to the required gear range. By calculating the virtual accelerator pedal opening, the virtual clutch opening, and the virtual gear range in this way, at the moment when the change of the virtual clutch opening to the engagement opening is completed, the virtual engine speed slightly decreases stepwise and then continuously increases. In addition, the required drive wheel torque temporarily increases and decreases and then continuously increases. The change of the required drive wheel torque is not immediately reflected in the acceleration, so the acceleration remains at zero during this period.

[0072] At time t17, the change of the virtual accelerator pedal opening to the required opening is completed. Thus, the upshift requested by the driver through the operation of the simulated shifter 24 for the electric vehicle 100 is completed. After the upshift is completed, the virtual accelerator pedal opening is fixed to the required opening, the virtual clutch opening is fixed to the engagement opening, and the virtual gear range is fixed to the required gear range. Roughly at this time, a longitudinal shift shock is generated in the electric vehicle 100, but its magnitude is suppressed to be low. After that, the acceleration changes to a magnitude corresponding to the virtual accelerator pedal opening and the virtual gear range.

[0073] According to the above shifting control, when the driver's upshift operation on the simulated shifter 24 is received, the opening of the virtual accelerator pedal of the virtual internal combustion engine changes from the required opening to the fully closed opening, i.e., 0%. Therefore, the virtual engine speed does not increase according to the operation of the driver's accelerator pedal 22, and the speed difference between the virtual engine speed and the virtual input shaft speed of the virtual manual transmission quickly converges within a predetermined range. Thus, even when an upshift operation is performed while the driver is stepping on the accelerator pedal 22, the situation where the virtual engine speed rises sharply or the shifting time becomes long will not occur, and the shifting can be completed without making the driver feel uncomfortable.

[0074] 4-2. Shifting control during downshifting

[0075] 4-2-1. With fuel compensation

[0076] Use Figure 6 A specific example of the shifting control during downshifting executed by the control device 101 will be described. In Figure 6 the shown timing chart, together with the shifting state ID and the transition condition ID, the changes over time of the downshift signal, the virtual accelerator pedal opening, the virtual clutch opening, the virtual gear range, the virtual engine torque, the virtual engine speed, the drive wheel torque required for the motors 4F and 4R, and the acceleration in the front-rear direction generated by the electric vehicle 100 are depicted. In this specific example, fuel compensation is used in the speed matching when engaging the virtual clutch.

[0077] According to Figure 6 the shown timing chart, a downshift signal is input from the gear sensor 14 to the control device 101 at time t21. Upon receiving the input of the downshift signal, the virtual accelerator pedal opening changes from the user-requested opening to 0% at a specified change speed. In Figure 6 the shown example, since the user-requested opening is already 0%, the virtual accelerator pedal opening is maintained at 0%. During this period, the virtual clutch opening is maintained at the engaged opening, and the virtual gear range is maintained at the current N gear. By calculating the virtual accelerator pedal opening, the virtual clutch opening, and the virtual gear range in this way, the virtual engine torque is maintained at a constant negative value, the virtual engine speed decreases, and the required drive wheel torque becomes larger in the negative direction.

[0078] At time t22, it is determined that the virtual accelerator pedal opening is 0%. In response to this, the virtual clutch opening changes from the engaged opening to the released opening at a specified change speed. During this period, the virtual accelerator pedal opening is maintained at 0%, and the virtual gear range is maintained at the current N gear. By calculating the virtual accelerator pedal opening, the virtual clutch opening, and the virtual gear range in this way, the virtual engine torque is maintained at a certain negative value, the virtual engine speed decreases, and the required drive wheel torque changes to increase to zero in the positive direction. Moreover, the deceleration generated by the vehicle (the acceleration in the rear direction of the vehicle) changes from increasing to decreasing.

[0079] At time t23, the change of the virtual clutch opening to the release opening is completed. In response to this, the virtual gear range is switched from the current N gear to the neutral gear. During this period, the virtual accelerator pedal opening is maintained at 0%, and the virtual clutch opening is maintained at the release opening. By calculating the virtual accelerator pedal opening, the virtual clutch opening, and the virtual gear range in this way, the virtual engine torque is maintained at a constant negative value, the decreasing speed of the virtual engine speed becomes larger, and the required drive wheel torque is maintained at zero. Moreover, the deceleration decreases to zero.

[0080] At time t24, a set time has elapsed since the switch from the virtual gear range to the neutral gear. In response to this, the virtual gear range is switched to the driver's required gear range (N-1 gear in the Figure 6 example shown), and the virtual accelerator pedal opening is switched from 0% to a predetermined fuel replenishment opening. During this period, the virtual clutch opening is maintained at the release opening. By calculating the virtual accelerator pedal opening, the virtual clutch opening, and the virtual gear range in this way, the virtual engine torque is increased, the virtual engine speed changes from decreasing to increasing, but the required drive wheel torque is maintained at zero. And, by continuously maintaining the drive wheel torque at zero, the longitudinal and lateral accelerations are also maintained at zero.

[0081] At time t25, the speed difference between the virtual engine speed and the virtual input shaft speed (N-1 gear speed in the Figure 6 example shown) converges to the allowable speed difference. In response to this, the virtual accelerator pedal opening is switched from the fuel replenishment opening to 0% again, and the virtual clutch opening changes from the release opening to the engagement opening at a specified change speed. During this period, the virtual gear range is fixed to the required gear range. By calculating the virtual accelerator pedal opening, the virtual clutch opening, and the virtual gear range in this way, the virtual engine torque is maintained at a certain negative value again, the virtual engine speed changes from increasing to decreasing, and the required drive wheel torque increases from zero to the negative side. And, the drive wheel torque increases to the negative side, so the deceleration increases.

[0082] At time t26, the change of the virtual clutch opening to the engagement opening is completed. In response to this, the virtual accelerator pedal opening changes from 0% to the user-required opening at a specified change speed. During this period, the virtual clutch opening is fixed to the engagement opening, and the virtual gear range is fixed to the required gear range. By calculating the virtual accelerator pedal opening, the virtual clutch opening, and the virtual gear range in this way, the virtual engine torque rises to the torque corresponding to the user-required opening, and the virtual engine speed changes to the speed determined by the required gear range and the vehicle speed. In addition, the required drive wheel torque changes from the change to the negative side to the change to the positive side. Moreover, after the direction of the change in the required drive wheel torque changes, a longitudinal shift shock is generated in the electric vehicle 100, but its magnitude is suppressed to be low.

[0083] At time t27, the change in the virtual accelerator pedal opening to the required opening is completed. As a result, the downshift requested by the driver through the operation of the simulated shifter 24 for the electric vehicle 100 is completed. After the downshift is completed, the virtual accelerator pedal opening is fixed to the required opening, the virtual clutch opening is fixed to the engaged state, and the virtual gear range is fixed to the required gear range.

[0084] According to the above shift control, the downshift operation of the simulated shifter 24 performed by the driver is received, so that the virtual accelerator pedal opening is forced to be the fully closed opening, that is, 0%, and fuel injection is performed corresponding to the switching of the virtual gear range to the required gear range. Therefore, the virtual engine speed does not increase according to the operation of the driver's accelerator pedal 22, and the speed difference between the virtual engine speed and the virtual input shaft speed of the virtual manual transmission quickly converges within a predetermined range by the effect of fuel injection. Thus, even when a downshift operation is performed while the driver is stepping on the accelerator pedal 22, the virtual engine speed does not rise sharply or the shift time does not become long, and the shift can be completed without discomfort to the driver.

[0085] 4-2-2. No fuel injection

[0086] Use Figure 7 Another specific example of the shift control during downshift performed by the control device 101 will be described. In Figure 7 the shown timing chart, the upshift signal, virtual accelerator pedal opening, virtual clutch opening, virtual gear range, virtual engine torque, virtual engine speed, drive wheel torque required for the motors 4F and 4R, and the acceleration in the front-rear direction generated by the electric vehicle 100 are depicted over time together with the shift state ID and transition condition ID. In this specific example, no fuel injection is used in the speed matching when engaging the virtual clutch, and instead, a semi-clutch is used. The driver can arbitrarily set which one of the shift control using this example and the shift control using fuel injection control through the HMI 20.

[0087] According to Figure 7 the shown timing chart, a downshift signal is input from the gear sensor 14 to the control device 101 at time t31. Receiving the input of the downshift signal, the virtual accelerator pedal opening changes from the user-requested opening to 0% at a specified change speed. In Figure 7 the shown example, since the user-requested opening is already 0%, the virtual accelerator pedal opening is maintained at 0%. During this period, the virtual clutch opening is maintained at the engaged opening, and the virtual gear range is maintained at the current N gear. By calculating the virtual accelerator pedal opening, virtual clutch opening, and virtual gear range in this way, the virtual engine torque is maintained at a constant negative value, the virtual engine speed decreases, and the required drive wheel torque becomes larger on the negative side.

[0088] At time t32, the virtual accelerator pedal opening is determined to be 0%. In response to this, the virtual clutch opening changes from the engaged opening to the released opening at a prescribed rate of change. During this period, the virtual accelerator pedal opening is maintained at 0%, and the virtual gear range maintains the current N gear. By calculating the virtual accelerator pedal opening, the virtual clutch opening, and the virtual gear range in this way, the virtual engine torque is maintained at a constant negative value, the virtual engine speed decreases, and the required drive wheel torque changes to an increase in the positive direction and increases to zero. Moreover, the deceleration generated by the vehicle (the acceleration in the rear direction of the vehicle) changes from increasing to decreasing.

[0089] At time t33, the change of the virtual clutch opening to the released opening is completed. In response to this, the virtual gear range is switched from the current N gear to the neutral gear. During this period, the virtual accelerator pedal opening is maintained at 0%, and the virtual clutch opening is maintained at the released opening. By calculating the virtual accelerator pedal opening, the virtual clutch opening, and the virtual gear range in this way, the virtual engine torque is maintained at a constant negative value, the rate of decrease of the virtual engine speed becomes larger, and the required drive wheel torque is maintained at zero. Moreover, the deceleration decreases to zero.

[0090] At time t34, a set time has elapsed since the virtual gear range was switched to the neutral gear. In response to this, the virtual gear range is switched to the driver's required gear range (N-1 gear in the example shown in Figure 7 . In addition, in this example, a larger allowable speed difference is achieved compared to the example using rev matching. Therefore, at time t34, the speed difference between the virtual engine speed and the virtual input shaft speed (N-1 gear speed in the example shown in Figure 7 ) converges to the allowable speed difference. In response to this, the virtual clutch opening changes from the released opening to the engaged opening at a prescribed rate of change. The rate of change from the released opening to the engaged opening in this example is lower than that in the example using rev matching to extend the semi-clutch period. The virtual accelerator pedal opening is also maintained at 0% after time t34. By calculating the virtual accelerator pedal opening, the virtual clutch opening, and the virtual gear range in this way, the virtual engine torque is maintained at a certain negative value, but the virtual engine speed changes from decreasing to increasing, and the required drive wheel torque changes from zero to a larger negative value. And, the drive wheel torque becomes larger in the negative direction, so that the deceleration increases.

[0091] At time t35, the change of the virtual clutch opening to the engaged opening is completed. In response to this, the virtual accelerator pedal opening changes from 0% to the user-requested opening at a specified rate of change. During this period, the virtual clutch opening is fixed to the engaged opening, and the virtual gear range is fixed to the requested gear range. By calculating the virtual accelerator pedal opening, the virtual clutch opening, and the virtual gear range in this way, the virtual engine torque rises to the torque corresponding to the user-requested opening, and the virtual engine speed changes to the speed determined by the requested gear range and the vehicle speed. In addition, the requested drive wheel torque changes from a change to the negative side to a change to the positive side. Moreover, after the direction of the change in the requested drive wheel torque changes, a longitudinal shift shock is generated in the electric vehicle 100, but its magnitude is suppressed to a low level.

[0092] At time t36, the change of the virtual accelerator pedal opening to the requested opening is completed. Thereby, the downshift requested by the driver for the electric vehicle 100 through the operation of the simulated shifter 24 is completed. After the downshift is completed, the virtual accelerator pedal opening is fixed to the requested opening, the virtual clutch opening is fixed to the engaged state, and the virtual gear range is fixed to the requested gear range.

[0093] According to the above shift control, in response to the driver's downshift operation on the virtual shifter 24, the virtual accelerator pedal opening is forcibly set to the fully closed opening, i.e., 0%. The semi-clutch starts corresponding to the switching of the virtual gear range to the requested gear range. Therefore, the virtual engine speed does not rise according to the driver's operation on the accelerator pedal 22. Through the effect of the semi-clutch, the speed difference between the virtual engine speed and the virtual input shaft speed of the virtual manual transmission quickly converges within a specified range. Thereby, even when the driver performs a downshift operation while stepping on the accelerator pedal 22, the situation where the virtual engine speed rises sharply or the shift time becomes long does not occur. The shift can be completed without causing discomfort to the driver.

[0094] 5. Others

[0095] The upshift control and the downshift control executed in the electric vehicle of this embodiment can also be applied to an electric vehicle having a simulated shifter and a simulated clutch pedal. In the case where the driver desires to assist the clutch operation, the operation of the driver on the virtual clutch pedal can also be invalidated and the virtual clutch opening calculated by the driver model can be used.

Claims

1. An electric vehicle having an electric motor as a driving source, characterized in that: have: Accelerator pedal; A simulated shifter that simulates the shifting operation of a manual transmission internal combustion engine vehicle; and a control device that receives the operation of the pseudo shifter to change the relationship between the vehicle speed of the electric vehicle, the accelerator pedal opening of the accelerator pedal, and the torque of the electric motor, The control device comprises: a memory storing a vehicle model obtained by modeling a virtual vehicle; and a processing circuit, in combination with the memory, to execute the vehicle model, The vehicle model includes: The engine model is obtained by modeling a virtual internal combustion engine; A clutch model is obtained by modeling a virtual clutch; a transmission model obtained by modeling a virtual manual transmission; and The driver model calculates a virtual accelerator pedal opening of the virtual internal combustion engine, a virtual clutch opening of the virtual clutch, and a virtual gear range of the virtual manual transmission based on the accelerator pedal opening, the gear position of the simulated shifter, the vehicle speed, and the virtual engine speed of the virtual internal combustion engine. The driver model is composed of: In response to the change of the gear position caused by the operation of the pseudo shifter, the virtual accelerator pedal opening degree is changed from the accelerator pedal opening degree to a fully closed opening degree, receiving completion of the change of the virtual accelerator pedal opening degree to the fully closed opening degree, and changing the virtual clutch opening degree from the engaged opening degree to the released opening degree, receiving completion of the change of the virtual clutch opening degree to the release opening degree, and changing the virtual gear range to a requested gear range corresponding to the gear position after the change, After the virtual gear range is changed to the required gear range, the virtual clutch opening is changed from the release opening to the engagement opening by accepting that the speed difference between the virtual engine speed and the virtual input shaft speed of the virtual manual transmission converges to within a predetermined range, In response to completion of the change of the virtual clutch opening degree to the engagement opening degree, the virtual accelerator pedal opening degree is changed from the fully closed opening degree to the accelerator pedal opening degree.

2. The electric vehicle according to claim 1, characterized in that: The driver model is configured to accept the completion of the change from the virtual gear range to the required gear range and temporarily increase the virtual accelerator pedal opening from the fully closed opening, and accept the convergence of the speed difference to the predetermined range and change the virtual clutch opening from the released opening to the engaged opening when the operation of the simulated shifter is a downshift operation.

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