Electric automobile

Abstract

The invention provides an electric vehicle having a motor as a drive source. An electric vehicle is provided with: a driving operation member for driving the electric vehicle; a speed change simulation operation part which simulates an operation part used for speed change operation of the manual speed change type internal combustion engine vehicle; a processor that controls the electric vehicle in accordance with an operation of the driving operation member; and a vehicle-mounted battery for charging electric energy generated during regenerative braking operation of the electric vehicle. The processor executes a control mode in which the operation of the analog shift operation member is associated with the torque of the motor in accordance with the selection of the driver.

Description

Technical Field

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

[0002] Japanese Patent No. 6787507 discloses an electric vehicle that can simulate the manual shifting operation of a vehicle equipped with a manual transmission using an internal combustion engine as a power source (hereinafter referred to as a manual transmission internal combustion engine vehicle) by controlling an electric motor.

[0003] Engine braking is a braking method unique to manual transmission internal combustion engine vehicles. According to the above technology, it is possible to experience the operation of a manual transmission internal combustion engine vehicle in an electric vehicle. However, although research has been conducted to reproduce clutch operation and shifter operation, no research has been conducted to reproduce engine braking without impairing the operational feel of operating an actual manual transmission internal combustion engine vehicle. Summary of the invention

[0004] According to one embodiment of the present disclosure, an electric vehicle has an electric motor as a driving source. The electric vehicle comprises: a driving operating component for driving the electric vehicle; a simulated speed change operating component that imitates the speed change operation of a manual transmission internal combustion engine vehicle; a processor that controls the electric vehicle according to the operation of the driving operating component; and an on-board battery that charges the electric energy generated when regenerative braking is working. The processor is configured to execute a control mode that associates the operation of the simulated speed change operating component with the torque of the electric motor according to the driver's selection. In the control mode, the processor is configured to: determine a virtual gear position based on the operation of the simulated speed change operating component; operate regenerative braking of a strength corresponding to the virtual gear position when the electric vehicle is in motion and there is no input of accelerator operation; and notify the driver of the gear position corresponding to the charge acceptance amount of the on-board battery.

[0005] According to the electric vehicle disclosed in the present invention, the engine braking of a manual transmission internal combustion engine vehicle is reproduced by regenerative braking. Regenerative braking is sometimes limited according to the amount of charge accepted by the vehicle battery. In such a case, the driver is notified of the gear corresponding to the amount of charge accepted. By adjusting the gear by the driver, the engine braking can be reproduced even when the amount of regenerative power that can be accepted is small. For the driver, the electric vehicle can be continuously driven without compromising the operational feel of a manual transmission internal combustion engine vehicle close to the real thing. The driver's satisfaction can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] 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 numerals represent like parts, and in which:

[0007] Figure 1 It is a diagram showing the structure of an electric vehicle according to an embodiment of the present disclosure.

[0008] Figure 2 This is a tree diagram showing an example of a control mode of the electric vehicle that can be selected by the control device.

[0009] Figure 3 This is a tree diagram showing an example of a control mode of the electric vehicle that can be selected by the control device.

[0010] Figure 4 This is a diagram showing the configuration of a control device related to driving control of an electric vehicle.

[0011] Figure 5 This is a diagram showing the structure of a control device related to sound control of an electric vehicle.

[0012] Figure 6 It is a diagram showing the structure of a control device related to virtual engine braking.

[0013] Figure 7 This is a conceptual diagram for explaining notification to the driver regarding the shift position.

[0014] Figure 8 1 is a flowchart showing a first example of processing of the control device related to notification to the driver.

[0015] Fig. 9 This is a flowchart showing a second example of the processing of the control device related to notification to the driver. DETAILED DESCRIPTION

[0016] Embodiments of the present disclosure will be described with reference to the drawings.

[0017] 1. The structure of the electric vehicle power system

[0018] Figure 1 1 is a diagram schematically showing the structure of an electric vehicle 100 according to an embodiment of the present disclosure. Figure 1 The configuration of the power system of the electric vehicle 100 will be described.

[0019] The electric vehicle 100 has two motors (M) 4F and 4R at the front and rear. The motors 4F and 4R have the function of converting the supplied power into torque and the function of converting the input torque into power. The motors 4F and 4R are, for example, three-phase AC motors. The front motor 4F is connected to the front drive shaft 5F that drives the front wheels 6F. The rear motor 4R is connected to the rear drive shaft 5R that drives the rear wheels 6R. The front wheels 6F are suspended on the left and right independent electronically controlled front suspension 7F. The rear wheels 6R are suspended on the left and right independent electronically controlled rear suspension 7R.

[0020] The motors 4F and 4R are used as a power source for driving. Inverters (INV) 3F and 3R are installed on the front motor 4F and the rear motor 4R, respectively. The front inverter 3F and the rear inverter 3R are connected to the battery (BATT) 2, respectively. The battery 2 stores electric energy for driving the motors 4F and 4R. That is, the electric vehicle 100 is a battery electric vehicle (BEV) that drives using the electric energy stored in the battery 2. The inverters 3F and 3R are, for example, voltage-type inverters, and the torque of the motors 4F and 4R is controlled by PWM control.

[0021] In addition, the front motor 4F and the rear motor 4R also have the function of a generator that generates regenerative power according to the torque input from the front drive shaft 5F and the rear drive shaft 5R, respectively. By operating the motors 4F and 4R as generators during the travel of the electric vehicle 100, the electric vehicle 100 can be decelerated by regenerative braking. At this time, the regenerative power generated by the motors 4F and 4R is charged to the battery 2 via the inverters 3F and 3R.

[0022] Furthermore, in the above description, the driving motors 4F and 4R also function as generators. However, the electric vehicle 100 may include driving motors and generators disposed separately from the driving motors at the front and rear.

[0023] 2. The structure of the control system of electric vehicles

[0024] Next, refer to Figure 1 The configuration of the control system of the electric vehicle 100 will be described.

[0025] The electric vehicle 100 is provided with a battery management system (BMS) 10. The battery management system 10 is a device that monitors the cell voltage, current, temperature, etc. of the battery 2. The battery management system 10 has a function of estimating the state of charge (SOC) of the battery 2. In addition, the functions of the battery management system 10 include a function of estimating the charge acceptance amount of the battery 2, that is, the amount obtained by subtracting the current charge amount from the full charge amount.

[0026] The electric vehicle 100 includes a vehicle speed sensor 11. At least one of the wheel speed sensors (not shown) provided at 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 includes an accelerator pedal stroke sensor 12. The accelerator pedal stroke sensor 12 is provided at the accelerator pedal 22, and outputs a signal indicating the amount of depression of the accelerator pedal 22, that is, the accelerator opening. Furthermore, the electric vehicle 100 includes a brake pedal stroke sensor 13. The brake pedal stroke sensor 13 is provided at the brake pedal 23, and outputs a signal indicating the amount of depression of the brake pedal 23, that is, the brake opening.

[0027] 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 also equipped with a simulated speed change operation component that imitates the operation component for the speed change operation of a manual transmission type internal combustion engine vehicle. The simulated speed change operation component includes the following simulated H-type shifter 24, simulated paddle shifter 25, and simulated clutch pedal 26.

[0028] The simulated H-type shifter 24 is a virtual shifter different from the original H-type shifter. The simulated H-type shifter 24 has a structure similar to the shift lever provided on the console, and can move along the H-shaped guide groove between the gear positions. However, since the electric vehicle 100 does not have a real transmission, the gear position of the simulated H-type shifter 24 is a virtual gear position. The simulated H-type shifter 24 is provided with a gear position sensor 14. The gear position sensor 14 outputs a signal indicating the gear position selected by the simulated H-type shifter 24.

[0029] The simulated paddle shifter 25 is a virtual shifter different from the original paddle shifter, which is a type of sequential shifter. The simulated paddle shifter 25 has a structure similar to a shift paddle mounted on a steering wheel, and can independently move the left and right paddles. The simulated paddle shifter 25 is provided with a paddle shift switch 15. The paddle shift switch 15 outputs an upshift signal when the right paddle is pulled, and outputs a downshift signal when the left paddle is pulled.

[0030] The simulated clutch pedal 26 is a virtual clutch pedal different from the original clutch pedal. The simulated clutch pedal 26 has a structure similar to the clutch pedal of the previous manual transmission internal combustion engine vehicle. For example, the simulated clutch pedal 26 has a reaction force mechanism that generates a reaction force relative to the driver's stepping. The position when no stepping force is applied is the starting position of the simulated clutch pedal 26. The position when stepped into the deepest position is the terminal position of the simulated clutch pedal 26. The driver can operate the simulated clutch pedal 26 from the starting position to the terminal position to overcome the reaction force from the reaction force mechanism. A clutch pedal stroke sensor 16 is provided on the simulated clutch pedal 26. The clutch pedal stroke sensor 16 outputs a signal indicating the amount of stepping on the simulated clutch pedal 26. The electric vehicle 100 does not have a real clutch, so the operation amount of the simulated clutch pedal 26, that is, the clutch opening is a virtual clutch opening.

[0031] In addition, the simulated clutch pedal 26 is a pedal-type operating device operated by foot, but a lever-type operating device or a dial-type operating device operated by hand may also be provided as the simulated clutch operating device. The simulated clutch operating device allows the driver to overcome the reaction force and operate from the starting position to the end position. As long as the driver can feel the operating feeling of the clutch pedal of the conventional manual transmission type internal combustion engine vehicle with the foot or hand, various structures can be adopted.

[0032] In addition, the electric vehicle 100 includes a human-machine interface (HMI) 20 as an interface with the driver and an in-vehicle speaker 21. The HMI 20 includes a touch panel display. The HMI 20 displays information on the touch panel display and receives input from the driver based on a touch operation on the touch panel display. The in-vehicle speaker 21 can provide information to the driver through voice and output a simulated engine sound described later.

[0033] 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 the battery management system 10, the vehicle speed sensor 11, the accelerator pedal travel sensor 12, the brake pedal travel sensor 13, the gear position sensor 14, the paddle shift switch 15, and the clutch pedal travel sensor 16, various sensors are mounted on the electric vehicle 100.

[0034] A typical control device 101 is an electronic control unit (ECU). The control device 101 may also be a combination of multiple ECUs. The control device 101 includes at least a processor 102 and a memory 103. The memory 103 includes a RAM for temporarily recording data and a ROM for storing a program 104 that can be executed by the processor 102 and various data 105 associated with the program. The program 104 is composed of multiple instructions. The processor 102 reads the program 104 and the data 105 from the memory 103 and executes them, and generates a control signal based on the signals obtained from each sensor. The number of processors 102 provided in the control device 101 may be one or more.

[0035] The control device 101 can control the electric vehicle 100 in various control modes. The control mode can be selected by the driver himself by touching the touch panel display of the HMI 20. In detail, by touching the touch panel display of the HMI 20, one or more programs 104 associated with each touch operation are read from the memory 103 and executed by the processor 102. The control mode of the electric vehicle 100 by the control device 101 that the driver can select by operating the HMI 20 is described below.

[0036] 3. Control mode of electric vehicles

[0037] Figure 2 and Figure 3 is a tree diagram showing an example of a control mode of the electric vehicle 100 that can be selected by the control device 101. Figure 2 The control tree shown displays the selection screen on the touch panel display.

[0038] The initial screen of HMI20 displays the option "control mode" OP000. By selecting the option "control mode" OP000, the option "automatic mode" OP110 and the option "manual mode" OP120 are displayed on the touch panel display. When the option "automatic mode" OP110 is selected, the control mode of the electric vehicle 100 is switched to the automatic 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 shifter operation of the simulated H-type shifter 24, the shifter operation of the simulated paddle shifter 25, and the clutch operation of the simulated clutch pedal 26 are invalidated.

[0039] When the option "manual mode" OP120 is selected, the control mode of the electric vehicle 100 is switched to the manual mode. The manual mode is a control mode for causing the electric vehicle 100 to operate like a manual transmission internal combustion engine vehicle. By selecting the option "manual mode" OP120, the option "shift mode" OP210, the option "engine characteristics" OP220, the option "engine sound" OP230, the option "drive mode" OP240, and the option "suspension characteristics" OP250 are displayed on the touch panel display. The driver can determine the characteristics of the manual transmission internal combustion engine vehicle that he wants the electric vehicle 100 to imitate by appropriately combining these options OP210-OP250.

[0040] The option "shift mode" OP210 is an option for selecting a shift mode of a manual transmission when the electric vehicle 100 operates like a manual transmission type internal combustion engine vehicle. Figure 2As shown, by selecting the option “shift mode” OP210, the option “paddle shift” OP311 and the option “lever shift” OP312 are displayed on the touch panel display. When the option “paddle shift” OP311 is selected, the shift mode of the manual transmission reproduced by the electric vehicle 100 is switched to the paddle shift mode. The paddle shift mode refers to a mode in which the simulated paddle shifter 25 is used for the shifter operation. In the paddle shift mode, the shifter operation of the simulated H-type shifter 24 is invalidated. In the paddle shift mode, the action when the gear ratio of the manual transmission is switched is reproduced by the shifter operation of the simulated paddle shifter 25. In addition, the clutch operation in the real paddle shift type manual transmission is automatically performed by the robot. Therefore, in the paddle shift mode, the clutch operation of the simulated clutch pedal 26 is not required. In the paddle shift mode, the clutch operation of the simulated clutch pedal 26 is invalidated.

[0041] When the option "lever shift" OP312 is selected, the lever shift mode is selected. The so-called lever shift mode is a mode in which the simulated H-type shifter 24 is used for the shifter operation. In the lever shift mode, the shifter operation of the simulated paddle shifter 25 is invalidated. In the lever shift mode, the action when the gear ratio of the manual transmission type is switched is reproduced by the shifter operation of the simulated H-type shifter 24. Among the real H-type shift type manual transmissions, there are manual transmissions in which the clutch operation is performed by the driver himself and manual transmissions in which the clutch operation is handed over to a robot. When the option "lever shift" OP312 is selected, the option "with clutch operation" OP411 and the option "without clutch operation" OP412 are displayed on the touch panel display. When the option "with clutch operation" OP411 is selected, the lever shift mode is switched to a mode that requires the clutch operation of the simulated clutch pedal 26. On the other hand, when the option "no clutch operation" OP412 is selected, the clutch operation of the simulated clutch pedal 26 is invalidated, and the lever shift mode is switched to a mode that does not require a clutch operation.

[0042] The option "engine characteristics" OP220 is an option for selecting the characteristics of the internal combustion engine when the electric vehicle 100 is operated like a manual transmission internal combustion engine vehicle. Figure 2As shown, by selecting the option "Engine Characteristics" OP220, the options "Low-Medium Rotation Type" OP321, the option "High Rotation Type" OP322, and the option "Global Type" OP323 are displayed on the touch panel display. When the option "Low-Medium Rotation Type" OP321 is selected, the characteristics of the internal combustion engine reproduced in the electric vehicle 100 are switched to a low-medium rotation type with a relatively high torque in the low-medium rotation area. When the option "High Rotation Type" OP322 is selected, the characteristics of the internal combustion engine reproduced in the electric vehicle 100 are switched to a high-rotation type with a relatively high torque in the high-rotation area. Then, when the option "Global Type" OP323 is selected, the characteristics of the internal combustion engine reproduced in the electric vehicle 100 are switched to a global type with the same torque in the entire area. However, the low-medium rotation type, the high rotation type, and the global type are merely examples of engine characteristics that can be reproduced by controlling the electric vehicle 100.

[0043] The option "engine sound" OP230 is an option for selecting the engine sound reproduced in the electric vehicle 100. Figure 2 As shown, by selecting the option “engine sound” OP230, the options “inline 4 turbocharged engine” OP331, the option “horizontally opposed 6 engine” OP332, and the option “V12 engine” OP333 are displayed on the touch panel display. When the option “inline 4 turbocharged engine” OP331 is selected, the engine sound reproduced in the electric vehicle 100 is switched to the engine sound of the inline 4 turbocharged engine. When the option “horizontally opposed 6 engine” OP332 is selected, the engine sound reproduced in the electric vehicle 100 is switched to the engine sound of the horizontally opposed 6 engine. And, when the option “V12 engine” OP333 is selected, the engine sound reproduced in the electric vehicle 100 is switched to the engine sound of the V12 engine. However, the inline 4 turbocharged engine, the horizontally opposed 6 engine, and the V12 engine are merely examples of the engine sounds that can be reproduced in the electric vehicle 100.

[0044] The option "drive mode" OP240 is an option for selecting the drive mode of the electric vehicle 100. Figure 3As shown, by selecting the option "drive mode" OP240, the option "four-wheel drive" OP341 and the option "rear-wheel drive" OP342 are displayed on the touch panel display. When the option "four-wheel drive" OP341 is selected, the drive mode of the electric vehicle 100 is switched to the four-wheel drive mode. In the four-wheel drive mode, the front wheel 6F is driven by the front motor 4F, and the rear wheel 6R is driven by the rear motor 4R. The torque distribution between the front wheel 6F and the rear wheel 6R can be fixed by the inverter 3F, 3R controlling the motor 4F, 4F, or can be variable. When the option "rear-wheel drive" OP342 is selected, the drive mode of the electric vehicle 100 is switched to the rear-wheel drive mode. In the rear-wheel drive mode, only the rear wheel 6R is driven by the rear motor 4R. However, in the electric vehicle 100, it is also possible to select a front-wheel drive mode in which only the front wheel 6F is driven by the front motor 4F instead of the rear-wheel drive mode or on the basis of the rear-wheel drive mode.

[0045] The option "suspension characteristics" OP250 is an option for selecting the suspension characteristics of the electric vehicle 100. Figure 3 As shown, by selecting the option "suspension characteristics" OP250, the options "soft" OP351, "hard" OP352, and "medium" OP353 are displayed on the touch panel display. When the option "soft" OP351 is selected, the suspension characteristics of the electric vehicle 100 are switched to the soft mode. In the soft mode, the damping force of the suspension 7F and 7R is reduced. In the case where the option "hard" OP352 is selected, the suspension characteristics of the electric vehicle 100 are switched to the hard mode. In the hard mode, the damping force of the suspension 7F and 7R is increased. And, in the case where the option "medium" OP353 is selected, the suspension characteristics of the electric vehicle 100 are switched to the medium mode. In the medium mode, the damping force of the suspension 7F and 7R is a damping force between the soft mode and the hard mode. However, since the suspension 7F and 7R are electronically controlled, their suspension characteristics can be adjusted widely. Therefore, the soft mode, the hard mode, and the medium mode are just examples of the suspension characteristics that can be realized in the electric vehicle 100. In addition, the drive mode and suspension characteristics can be selected not only in manual mode but also in automatic mode.

[0046] By operating the touch panel display of HMI20 according to the control tree described above, the control mode of the electric vehicle 100 can be switched to the driver's preference. The switchable control modes include a mode related to the driving control of the electric vehicle 100 and a mode related to the sound control of the electric vehicle 100. Specifically, the mode related to the option "engine sound" OP230 is a mode related to the sound control. The other modes are related to the driving control. In the following chapters, the driving control and sound control of the electric vehicle 100 performed by the control device 101 are described.

[0047] 4. Driving control of electric vehicles

[0048] Figure 4 1 is a diagram showing a structure of a control device 101 related to driving control of an electric vehicle 100. In detail, Figure 4 The configuration related to the torque control in particular among the driving control is shown. The processor 102 functions as a driving control device by executing one or more driving control programs 104 stored in the memory 103 .

[0049] A control mode signal is input from the HMI 20 to the control device 101 as a driving control device. The control mode signal contains information related to the control mode selected by the driver. The control device 101 performs processing P110 based on the control mode signal. In processing P110, the control mode is switched according to the control mode signal. The switching of the control mode particularly affects the driving control, that is, the switching between the automatic mode and the manual mode.

[0050] When the control mode is switched to the automatic mode, the control device 101 executes the process P120 for torque calculation in the automatic mode. In the process P120, the control device 101 obtains the vehicle speed from the signal of the vehicle speed sensor 11 and obtains the accelerator opening from the signal of the accelerator pedal stroke sensor 12. The control device 101 has a motor torque map with the accelerator opening and the vehicle speed as parameters. The control device 101 inputs the vehicle speed and the accelerator opening into the motor torque map and controls the inverters 3F and 3R so that the motors 4F and 4R generate the torque obtained by the motor torque map.

[0051] When the control mode is switched to the manual mode, the control device 101 executes processing P130 for torque calculation in the manual mode. Processing P130 includes processing P131 for calculating the torque generated by the drive wheel. In addition, processing P130 includes processing P132 and processing P133. Processing P132 is a process for calculating the torque generated by the front motor 4F. Processing P133 is a process for calculating the torque generated by the rear motor 4R. Processing P132 and processing P133 are executed based on the drive wheel torque calculated in processing P130 and the torque distribution between the front wheel 6F and the rear wheel 6R.

[0052] The vehicle model MOD01 is used in the calculation of the drive wheel torque in processing P131. The vehicle model MOD01 includes an engine model MOD11, a clutch model MOD12, and a transmission model MOD13. The engine virtually realized by the vehicle model MOD01 is called a virtual engine. The clutch virtually realized is called a virtual clutch. The transmission virtually realized is called a virtual transmission. In the engine model MOD11, the virtual engine is modeled. In the clutch model MOD12, the virtual clutch is modeled. In the transmission model MOD13, the virtual transmission is modeled.

[0053] The engine model MOD11 calculates the virtual engine speed and the virtual engine torque. The virtual engine speed is calculated based on the vehicle speed, the comprehensive reduction ratio, and the slip ratio of the virtual clutch. The virtual engine torque is calculated based on the virtual engine speed and the accelerator opening. The vehicle speed is obtained from the signal of the vehicle speed sensor 11. The accelerator opening is obtained based on the signal of the accelerator pedal stroke sensor 12. The comprehensive reduction ratio is a numerical value obtained by multiplying the speed ratio of the virtual transmission by the reduction ratio determined by the mechanical structure from the virtual transmission to the drive wheels. In the engine model MOD11, the relationship between the virtual engine speed and the virtual engine torque is specified for each accelerator opening. The engine characteristics of the engine model MOD11 can be selected by the driver through the operation of the HMI20. Figure 2 In the example shown, the engine characteristics can be selected from a low-medium rotation type, a high rotation type, and a full-range type.

[0054] The clutch model MOD12 calculates the torque transfer gain. The torque transfer gain is a gain for calculating the torque transfer degree of the virtual clutch corresponding to the clutch opening. When the lever shift mode with clutch operation is selected as the shift mode, the clutch opening is obtained based on the signal of the clutch pedal stroke sensor 16. The clutch opening is 0% at the starting position of the simulated clutch pedal 26 and 100% at the terminal position of the simulated clutch pedal 26. In the clutch model MOD12, the torque transfer gain is assigned to the clutch opening. The torque transfer gain is converted into the clutch torque capacity of the virtual clutch, that is, the virtual clutch torque capacity. Then, based on the comparison between the virtual clutch torque capacity and the virtual engine torque calculated by the engine model MOD11, the virtual clutch torque input from the virtual clutch to the virtual transmission is calculated. In addition, in the clutch model MOD12, the value after subtracting the torque transfer 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.

[0055] When the paddle shift mode is selected as the shift mode, the clutch opening input to the clutch model MOD12 is calculated using the clutch operation model. In addition, when the clutchless lever shift mode is selected as the shift mode, the clutch opening input to the clutch model MOD12 is also calculated using the clutch operation model. The clutch operation model is a model that imitates the clutch operation of a model driver. When the paddle shift mode is selected, the vehicle speed, the virtual engine speed, and the signal from the paddle shift switch 15 are input to the clutch operation model. When the clutchless lever shift mode is selected, the vehicle speed, the virtual engine speed, and the signal from the gear position sensor 14 are input to the clutch operation model.

[0056] The signal from the paddle shift switch 15 and the signal from the gear position sensor 14 are used to measure the timing of the clutch operation. When the driver's shifter operation is detected based on the signal from the paddle shift switch 15 or the signal from the gear position sensor 14, in the clutch operation model, the clutch opening is set to the maximum to cut off the virtual clutch. The vehicle speed and the virtual engine speed are used for the calculation of the clutch opening. In the clutch operation model, the clutch opening is calculated based on the speed difference between the speed of the input shaft of the virtual transmission and the virtual engine speed so that the speed of the input shaft of the virtual transmission calculated based on the vehicle speed is smoothly consistent with the virtual engine speed.

[0057] The transmission model MOD13 calculates a virtual speed ratio. The virtual speed ratio is a speed ratio determined by a virtual gear position in a virtual transmission. The virtual speed ratio is set for each gear position. The maximum virtual speed ratio is set for the 1st speed, and the virtual speed ratio is reduced in the order of the 2nd speed, the 3rd speed, the 4th speed, ... In the lever shift mode, the gear position corresponds to the signal of the gear position sensor 14 one by one. In the paddle shift mode, the gear position is shifted up one level by receiving the upshift signal of the paddle shift switch 15, and the gear position is shifted down one level by receiving the downshift signal of the paddle shift switch 15. In addition, in the simulated H-type shifter 24, the number of gears is physically determined, while in the simulated paddle shifter 25, there is no physical restriction on the number of gears. Therefore, the transmission model MOD13 can also be made different in the lever shift mode and the paddle shift mode, so that the number of gears in the paddle shift mode is greater than the number of gears in the lever shift mode.

[0058] The transmission model MOD13 calculates the virtual transmission torque using the virtual gear ratio and the virtual clutch torque. The virtual transmission torque is a virtual torque output from the virtual transmission. The control device 101 controls the inverters 3F and 3R so that the output torque of the motors 4F and 4R changes according to the virtual transmission torque. The virtual transmission torque changes discontinuously according to the switching of the virtual gear ratio. The discontinuous change of the virtual transmission torque causes the electric vehicle 100 to generate a torque shock, which behaves like a vehicle with a stepped transmission.

[0059] The vehicle model MOD01 calculates the drive wheel torque based on the virtual transmission torque and the reduction ratio. When the four-wheel drive mode is selected as the drive mode, 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 distribution to the front wheel 6F and the rear wheel 6R can be fixed or can be changed actively or passively. When the rear-wheel drive mode is selected as the drive mode, the drive wheel torque becomes the sum of the torques acting on the left and right rear wheels 6R.

[0060] In processing P132, the torque of the front motor 4F in the manual mode (front motor torque) is calculated by multiplying the drive wheel torque calculated in processing P131 by the torque distribution rate to the front wheels 6F and the reduction ratio from the output shaft of the front motor 4F to the front wheels 6F. The control device 101 controls the front inverter 3F so that the front motor 4F generates the front motor torque calculated in processing P132.

[0061] In process P133, the torque of the rear motor 4R in the manual mode (rear motor torque) is calculated by multiplying the drive wheel torque calculated in process P131 by the torque distribution rate to the rear wheel 6R and the reduction ratio from the output shaft of the rear motor 4R to the rear wheel 6R. The control device 101 controls the rear inverter 3R so that the rear motor 4R generates the rear motor torque calculated in process P133.

[0062] In addition, Figure 4 In the structure shown, the battery management system 10 and the brake pedal travel sensor 13 are not necessarily required for the above-mentioned driving control. However, in the case where the switching of the control mode affects the SOC of the battery 2, the signal of the battery management system 10 can also be used as information for determining whether the control mode can be switched. In addition, in the case where the operation method of the electric vehicle 100 changes significantly, such as the switching between the automatic mode and the manual mode, the stepping of the brake pedal 23 can also be used as a switching condition. In this case, the signal of the brake pedal travel sensor 13 can be used as information for determining that the brake pedal 23 is stepped on.

[0063] 5. Voice control for electric vehicles

[0064] Figure 5 1 is a diagram showing the structure of a control device 101 related to sound control of an electric vehicle 100. The processor 102 functions as a sound control device by executing one or more sound control programs 104 stored in a memory 103. The processor 102 that functions as a driving control device and the processor 102 that functions as a sound control device may be different processors or the same processor.

[0065] The control device 101 as a sound control device can generate an artificially generated sound from the in-vehicle speaker 21. One of the artificial sounds is a simulated engine sound similar to the engine sound in a conventional internal combustion engine vehicle. When a control mode signal indicating that the manual mode is selected from the HMI 20 is input, the control device 101 as a sound control device executes processing P140. In processing P140, a simulated engine sound is generated based on the virtual engine torque and the virtual engine speed calculated in processing P131.

[0066] In process P140, the engine sound selected by the HMI 20 is used as the sound source of the simulated engine sound generated from the in-vehicle speaker 21. Figure 2 In the example shown, engine sounds selected from a straight 4 turbocharged engine, a horizontally opposed 6 engine, and a V12 engine are used as the sound source for simulating the engine sound. However, in process P140, the sound of the sound source is not used directly. In process P140, the sound pressure of the sound source is changed, for example, by an amplifier, and the frequency of the sound source is changed, for example, by a frequency modulator.

[0067] Processing P140 includes processing P141 for calculating the engine sound pressure and processing P142 for calculating the engine sound frequency. In processing P141, the sound pressure of the simulated engine sound is calculated based on the virtual engine torque using sound pressure mapping M11. The sound pressure mapping M11 is produced in such a way that the sound pressure increases as the virtual engine torque increases. In processing P142, the frequency of the simulated engine sound is calculated based on the virtual engine speed using frequency mapping M12. The frequency mapping M12 is produced in such a way that the frequency increases as the virtual engine speed increases. The virtual engine torque and the virtual engine speed change according to the driver's accelerator operation, the shifter operation, and the clutch operation. By changing the sound pressure and frequency of the simulated engine sound according to the virtual engine torque and the virtual engine speed that change in this way, the driver can be given a sense of reality as if he were driving a real manual transmission internal combustion engine vehicle.

[0068] 6. Reproduction of engine braking based on regenerative braking

[0069] 6-1. Overview

[0070] The driver of the electric vehicle 100 switches the control mode to the manual mode by operating the HMI 20, and can experience the operation of a manual transmission internal combustion engine vehicle in the electric vehicle 100. While the control mode is set to the manual mode, the electric vehicle 100 is controlled to reproduce the behavior of a manual transmission internal combustion engine vehicle.

[0071] One of the behaviors unique to manual transmission internal combustion engine vehicles is engine braking. In the manual mode of the electric vehicle 100, the operation of the engine braking is also reproduced. However, since the electric vehicle 100 does not have a real transmission, the engine braking that works in the manual mode is a virtual engine braking simulated by regenerative braking. Hereinafter, the engine braking virtually realized by regenerative braking is referred to as virtual engine braking.

[0072] Figure 6 1 is a diagram showing processing related to the operation of virtual engine brake performed by control device 101. The processing related to the operation of virtual engine brake includes processing P151 for determining whether virtual engine brake is operating and processing P152 for operating regenerative brake. These processing are performed by control device 101 as a travel control device.

[0073] In processing P151, a determination is made as to whether the engine brake is activated. When the electric vehicle 100 is in driving and there is no input of the accelerator operation in the state where the manual mode is selected, the control device 101 activates the virtual engine brake. Whether the manual mode is selected is obtained based on the control mode signal input from the HMI20. The presence or absence of the accelerator operation input, that is, whether the accelerator pedal 22 is stepped on by the driver is obtained from the signal of the accelerator pedal stroke sensor 12. In addition, whether the electric vehicle 100 is in driving can be obtained from the signal of the vehicle speed sensor 11, and when the vehicle speed is not 0, it is determined that the electric vehicle 100 is in driving. Based on the signals obtained from the HMI20, the vehicle speed sensor 11, and the accelerator pedal stroke sensor 12, the control device 101 decides to activate the virtual engine brake when the electric vehicle 100 is driving in the manual mode and the accelerator pedal 22 is not stepped on.

[0074] When it is determined that the virtual engine brake is activated, the control device 101 executes processing P152. In processing P152, the motors 4F and 4R are controlled in such a way that the torque input from the front drive shaft 5F and the rear drive shaft 5R is converted into regenerative power so that the regenerative brake is activated. The intensity of the regenerative brake is determined according to the virtual gear position. The engine brake of the manual transmission internal combustion engine vehicle is reproduced by the regenerative brake.

[0075] By reproducing the engine brake in this way, the behavior of the electric vehicle 100 can be made closer to that of a real manual transmission internal combustion engine vehicle. However, unlike the engine brake in an actual manual transmission internal combustion engine vehicle, sometimes the use of regenerative braking is restricted according to the state of the battery 2. Specifically, when the charge acceptance amount of the battery 2 is insufficient, there is no charging space for the regenerative power generated by the regenerative braking, so the use of the regenerative braking is restricted.

[0076] Here, the larger the speed ratio, the stronger the engine braking effect. In the manual mode of the electric vehicle 100, in order to reproduce the engine braking, the larger the virtual speed ratio, the stronger the regenerative braking is. In other words, if the virtual speed ratio is small, the engine braking can be reproduced even without making the regenerative braking work strongly. The virtual speed ratio increases as the virtual gear moves toward the downshift side. Therefore, when the electric vehicle 100 is in manual mode and the amount of charge received is insufficient or predicted to be insufficient, the driver is notified about the virtual gear. The following is a specific example to illustrate the notification to the driver. In addition, the following assumes that the virtual gear is composed of 6 gears from 1st to 6th speed, but the same notification is made for the case where the number of gears of the virtual gear is more or less than that.

[0077] 6-2. Use scenarios of virtual engine braking

[0078] exist Figure 7 , as an example of a scenario in which the virtual engine brake is often used, a scenario in which the electric vehicle 100 is traveling on a mountain road 200 with a continuous downhill slope is shown.

[0079] At time (a) when the electric vehicle 100 approaches the mountain road 200, the battery 2 has a sufficiently high charge level. When the electric vehicle 100 enters the mountain road 200, the driver downshifts the virtual gear to activate the virtual engine brake in order to suppress the use of the brake pedal 23.

[0080] During a period of time after the start of the driving on the mountain road 200, the charge receiving amount is sufficient, and the virtual engine brake can be used regardless of the position of the virtual gear. During this period, the driver is not notified about the gear. Alternatively, the driver is notified that all gears can be selected.

[0081] By using the virtual engine to charge the battery 2, at the time point (b), when the virtual engine brake is used at the first speed, the charge receiving amount begins to be insufficient. Therefore, a notification is given to the driver to urge him to select a gear that is closer to the upshift side than the first speed, that is, the second speed or higher. The driver sets the gear to the second speed or higher according to the notification, so that the virtual engine brake can continue to be used.

[0082] When the charging of battery 2 is further progressed and the charge receiving amount decreases, and the charge receiving amount begins to be insufficient when the virtual engine brake is used at 2nd speed, the driver is notified to select a gear higher than 3rd speed. The driver sets the gear higher than 3rd speed according to the notification, and the virtual engine brake can continue to be used.

[0083] The same applies to the following. When the charging of the battery 2 progresses and the charge receiving amount decreases, the driver is notified to select a shift position according to the charge receiving amount.

[0084] 6-3. The first case of treatment

[0085] Figure 8 It is a flowchart which shows an example of the process performed by the control device 101. Figure 8 The series of processes shown are repeatedly executed in a predetermined control cycle, for example, while the electric vehicle 100 is started. The series of processes are realized by the processor 102 executing the program 104 .

[0086] according to Figure 8 In the flow shown, first, in step S101, it is determined whether the virtual engine brake is in operation. If the virtual engine brake is not in operation, a series of processes are terminated.

[0087] In step S101, the control device 101 may determine whether the electric vehicle 100 is in a virtual engine braking usage scenario, such as a scenario of driving on a mountain road with a continuous downhill slope, instead of simply determining whether the virtual engine braking is temporarily working. The virtual engine braking usage scenario referred to here is a scenario in which the virtual engine braking is assumed to be used continuously to some extent. The control device 101 may also determine that the electric vehicle 100 is in a virtual engine braking usage scenario when the virtual engine braking is continuously working for more than a specified time, or when the frequency of the virtual engine braking operation is more than a specified frequency within a certain period of time.

[0088] When the virtual engine brake is in operation, step S102 is executed. In step S102, it is determined whether the charge acceptance amount of the battery 2 is less than the specified amount S1. The specified amount S1 is the lower limit of the charge acceptance amount that enables the virtual engine brake to operate even when the virtual gear is the first speed. The control device 101 obtains the charge acceptance amount based on the signal input from the battery management system 10. When the charge acceptance amount is greater than the specified amount S1, a series of processes are terminated.

[0089] When the charge acceptance amount is less than the prescribed amount S1, step S103 is executed. In step S103, it is determined whether the charge acceptance amount is less than the prescribed amount S2. The prescribed amount S2 is the lower limit of the charge acceptance amount that can enable the virtual engine brake to operate when the virtual gear is 2nd speed or above. The prescribed amount S2 is less than the prescribed amount S1.

[0090] When the charge received amount is greater than or equal to the predetermined amount S2, step S104 is executed. In step S104, a notification is made to urge the driver to select a gear position of 2 or higher. The HMI 20 makes the notification by displaying the selectable gear position on the touch panel display. Alternatively, the notification may be made by sound via the in-vehicle speaker 21.

[0091] On the other hand, if the charge acceptance amount is less than the prescribed amount S2, step S105 is executed. In step S105, it is determined whether the charge acceptance amount is less than the prescribed amount S3. The prescribed amount S3 is the lower limit of the charge acceptance amount that can enable the virtual engine brake to operate when the virtual gear is 4 speed or above. The prescribed amount S3 is less than the prescribed amount S2.

[0092] When the charge received amount is equal to or greater than the predetermined amount S3, step S106 is executed. In step S106, a notification is made to urge the driver to select a gear position of 4th speed or higher. The notification is made by display or sound.

[0093] On the other hand, when the charge received amount is less than the predetermined amount S3, step S107 is executed. In step S107, a notification is made to urge the driver to change the gear position to the 6th speed. The notification is made by display or sound.

[0094] In this way, the electric vehicle 100 requests the driver to select a gear corresponding to the charge acceptance amount during deceleration based on the virtual engine brake when the electric vehicle 100 is in manual mode. More specifically, the electric vehicle 100 determines whether the current charge acceptance amount is less than the threshold value of the charge acceptance amount set for each gear. Moreover, when the current charge acceptance amount is less than the threshold value set for any gear, the driver is notified to select a gear on the upshift side of the gear. At this time, as in the above-mentioned steps S104 and S106, when there are multiple selectable gears, the driver is notified of the multiple gears. In addition, the threshold value of each gear does not necessarily need to be set for all gears. In the above-mentioned example, the case of performing three-stage notifications to urge the selection of a gear of 2 or more speeds, 4 or more speeds, and 6 speeds is described. Alternatively, the notification of the selectable gear can also be switched more finely than the above-mentioned example. That is, in addition to the above-mentioned notification, a notification urging the selection of a gear of 3 or more speeds and a notification urging the selection of a gear of 5 or more speeds can also be performed.

[0095] 6-4. Effect

[0096] According to the above-mentioned processing, when the charge acceptance amount of the battery 2 decreases, the driver is urged to keep the virtual gear position on the upshift side. By selecting the gear position on the upshift side, the intensity and frequency of use of the virtual engine brake are reduced, and the engine brake can be reproduced even when the charge acceptance amount is small. In this way, even when the charge acceptance amount of the battery 2 decreases, the manual mode can be continued without compromising the operational feel of a manual transmission internal combustion engine vehicle. As a result, the satisfaction of the driver who wants to experience an operation closer to a real manual transmission internal combustion engine vehicle can be improved. This is particularly effective in situations such as downhill where it is assumed that the amount of regenerative power generated by using more virtual engine brakes increases.

[0097] 6-5. Second example of treatment

[0098] Fig. 9 This is a flowchart showing another example of the processing performed by the control device 101. Fig. 9 The series of processes shown are repeatedly executed in a predetermined control cycle, for example, while the electric vehicle 100 is started. The series of processes are realized by the processor 102 executing the program 104 .

[0099] according to Fig. 9 In the flow shown, first, in step S201, it is determined whether the virtual engine brake is in operation. If the virtual engine brake is not in operation, a series of processes are terminated.

[0100] In step S201, the control device 101 may also determine whether the electric vehicle 100 is in a virtual engine braking use scenario. In this case, when it is determined that it is not a virtual engine braking use scenario, a series of processes are terminated. When it is determined that it is a virtual engine braking use scenario, the process proceeds to step S202.

[0101] When the virtual engine brake is in operation, step S202 is executed. In step S202, it is determined whether the charge acceptance amount of the battery 2 is less than a prescribed amount. The prescribed amount here may be the same as the prescribed amount S1 in step S102, or may be less than the prescribed amount S1. When the charge acceptance amount is greater than the prescribed amount, a series of processes are terminated.

[0102] The determination in step S202 may be performed based on the SOC. In this case, if the SOC is less than a predetermined ratio, a series of processes are terminated. If the SOC is greater than the predetermined ratio, the process proceeds to step S203.

[0103] When the charge received amount is less than the prescribed amount, step S203 is executed. In step S203, the control device 101 requests the driver not to perform a downshift. For example, the control device 101 displays a message such as "downshift is restricted" on the HMI 20.

[0104] In this way, the control device 101 can also request the driver not to downshift when the charge acceptance amount is less than the specified amount. In this case, as in the first example, by keeping the virtual gear position on the upshift side, the intensity and operating frequency of the virtual engine brake are reduced, and the charge acceptance amount can at least reproduce the engine brake through regenerative braking. In this way, the operating feel as if operating a real manual transmission internal combustion engine vehicle can be maintained regardless of the charge acceptance amount.

[0105] 6-6. Modifications

[0106] exist Fig. 9In the process, multiple thresholds may be set for the charge acceptance amount, and the minimum gear allowed may be set for each threshold. For example, the 4th speed may be set as the minimum gear for the first threshold of the charge acceptance amount, and when the charge acceptance amount is less than the first threshold, a request is made not to downshift to a speed lower than the 3rd speed. In addition, for a second threshold smaller than the first threshold, the 3rd speed may be set as the minimum gear, and when the charge acceptance amount is less than the second threshold, a request is made not to downshift to a speed lower than the 2nd speed.

[0107] exist Fig. 9 In step S202 of the process, it can also be determined whether an abnormality has occurred in battery 2. If no abnormality has occurred in battery 2, a series of processes are terminated. If an abnormality has occurred in battery 2, the process proceeds to step S203. When an abnormality has occurred in battery 2, battery 2 may also be unable to receive regenerative power. In such a case, by prompting the driver to keep the virtual gear position on the upshift side, the frequency of use of virtual engine braking can also be reduced. The operating feel of a real manual transmission internal combustion engine vehicle can be maintained.

[0108] In addition, the control device 101 may also reduce the charge receiving amount of the battery 2 in advance according to the prediction of the amount of regenerative power generated. For example, the control device 101 communicates with the navigation system and obtains in advance the route that the electric vehicle 100 is scheduled to travel. Furthermore, when the route that the electric vehicle 100 is scheduled to travel includes a route with a continuous downhill slope, the battery 2 may be discharged to reduce the charge amount before reaching the route with a continuous downhill slope.

Claims

1. An electric vehicle having an electric motor as a driving source, characterized in that: include: A driving operating component, used for driving the electric vehicle; A simulated shift operating member that simulates a shift operation for a manual transmission type internal combustion engine vehicle; a processor that controls the electric vehicle according to the operation of the driving operation component; and An on-board battery is used to charge the electric energy generated when the electric vehicle is in regenerative braking operation. The processor is configured to execute a control mode that associates the operation of the pseudo speed change operating member with the torque of the electric motor in accordance with a driver's selection. In the control mode, the processor is configured to: determining a virtual gear position based on the operation of the simulated shift operating member; When the electric vehicle is running and there is no accelerator operation input, operating the regenerative braking with a strength corresponding to the virtual gear position; A gear position corresponding to the charge acceptance amount of the on-vehicle battery is notified to the driver of the electric vehicle.

2. The electric vehicle according to claim 1, characterized in that: setting a threshold value of the charge acceptance amount for each of the virtual gears, The processor is composed of: When the control mode is executed and regenerative braking of a strength corresponding to the virtual gear position is in operation, determining whether the charge acceptance amount is less than the threshold value; When the charge reception amount is smaller than a threshold value set for a first virtual gear position, a gear position on an upshift side relative to the first virtual gear position is notified to the driver.

3. The electric vehicle according to claim 2, characterized in that: The processor is configured to notify the driver of the plurality of gear positions when the gear position on the upshift side relative to the first virtual gear position includes a plurality of gear positions.

4. The electric vehicle according to claim 1, characterized in that: The processor is composed of: When the control mode is executed and regenerative braking of a strength corresponding to the virtual gear position is in operation, determining whether the charge acceptance amount is less than a predetermined amount; When the received charge amount is less than the predetermined amount, the driver is requested not to perform a downshift.

5. The electric vehicle according to claim 4, characterized in that: The processor is configured to determine that the charge received amount is less than the predetermined amount when the charge rate of the vehicle-mounted battery is equal to or higher than a predetermined ratio or when an abnormality occurs in the vehicle-mounted battery.

6. The electric vehicle according to any one of claims 1 to 5, characterized in that: The driving operating components include an accelerator pedal, The simulated speed change operation component comprises: Simulated H-pattern shifter, which mimics the H-pattern shifter of a manual transmission; and Simulated clutch operating device, imitates the clutch operating device.

7. The electric vehicle according to claim 6, characterized in that: The processor is configured to change the torque of the electric motor in accordance with the gear position selected by the pseudo H-type shifter, the operation amount of the pseudo clutch operation device, and the operation amount of the accelerator pedal in the control mode.

8. The electric vehicle according to any one of claims 1 to 5, characterized in that: The driving operating components include an accelerator pedal, The simulated shift operating component includes a simulated sequential shifter that imitates a sequential shifter of a manual transmission.

9. The electric vehicle according to claim 8, characterized in that: The processor is configured to change the torque of the electric motor according to the gear position selected by the pseudo sequential shifter and the operation amount of the accelerator pedal in the control mode.

10. The electric vehicle according to any one of claims 1 to 5, characterized in that: The driving operating components include an accelerator pedal, The simulated speed shift operating component includes a simulated H-type shifter that imitates an H-type shifter of a manual transmission.

11. The electric vehicle according to claim 10, characterized in that: The processor is configured to change the torque of the electric motor in accordance with the gear position selected by the pseudo H-type shifter and the operation amount of the accelerator pedal in the control mode.

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