Electric vehicle and control device

Abstract

To provide an electric vehicle that enables a driver to bodily sense an acceleration feeling which is equivalent to an acceleration feeling in a virtual vehicle having acceleration characteristics with an acceleration capability thereof exceeding an acceleration capability of the electric vehicle.SOLUTION: The electric vehicle comprises a processing circuit and a storing device. The storing device stores a database for managing a plurality of vehicle models modeled after a plurality of virtual vehicles. The processing circuit reads, from the database, a target vehicle model corresponding to a target virtual vehicle selected by a driver, and calculates virtual acceleration of the target virtual vehicle by using the target vehicle model. When determining that the virtual acceleration exceeds realizable acceleration of the electric vehicle in an accelerating period of the electric vehicle in which an accelerator pedal is depressed, the processing circuit executes a correction process for correcting the virtual acceleration so as to reshape temporal change of the virtual acceleration in accordance with the excess. Further, the processing circuit controls an electric motor so that acceleration of the electric vehicle becomes equal to the corrected virtual acceleration.SELECTED DRAWING: Figure 6

Description

[Technical Field]

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

[0002] An electric motor can be controlled to output a desired motor torque by controlling the applied voltage and magnetic field. Taking advantage of this, technologies have been devised to appropriately control the electric motor of an electric vehicle to reproduce various driving sensations in the electric vehicle. For example, Patent Document 1 discloses a technology for simulating the driving sensation associated with manual gear shifting in a manual transmission vehicle in an electric vehicle. [Prior art documents] [Patent documents]

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

[0004] One of the elements that characterize the driving feel of each vehicle is the feeling of vehicle acceleration in response to driving operations. The feeling of vehicle acceleration is an important factor when a driver feels enjoyment in driving a vehicle. In particular, preferences for the feeling of vehicle acceleration vary from driver to driver. Drivers may also want to enjoy a variety of vehicle acceleration feelings depending on their mood.

[0005] Therefore, the inventors of the present disclosure have studied a technology that uses a vehicle model to calculate virtual acceleration when a virtual vehicle is driven, and controls the electric motor so that the calculated virtual acceleration is realized in an electric vehicle. A vehicle model can be provided for each of multiple virtual vehicles. Therefore, this technology makes it possible to simulate the acceleration sensations of multiple virtual vehicles in a single electric vehicle.

[0006] However, the acceleration that an electric vehicle can achieve is naturally limited by the motor torque output characteristics of the electric vehicle's electric motor. Therefore, for a virtual vehicle with acceleration characteristics that exceed the acceleration capacity of the electric vehicle, the electric vehicle may not be able to directly reproduce the acceleration characteristics. As a result, there is a problem that the acceleration feel of such a virtual vehicle cannot be reproduced in the electric vehicle. On the other hand, increasing the acceleration capacity of the electric vehicle to enable the acceleration characteristics of such a virtual vehicle to be realized would unnecessarily increase the cost of the electric vehicle.

[0007] One object of the present disclosure is to provide an electric vehicle that allows a driver to experience a feeling of acceleration equivalent to that of a virtual vehicle that has acceleration characteristics that exceed the acceleration capacity of the electric vehicle. [Means for solving the problem]

[0008] A first aspect of the present disclosure relates to an electric vehicle having an electric motor as a drive source.

[0009] The electric vehicle includes an accelerator pedal, a processing circuit, and a storage device. The storage device stores a database that manages multiple vehicle models that model multiple virtual vehicles with different acceleration characteristics in response to a driver's driving operation. The processing circuit retrieves from the database a target vehicle model corresponding to a target virtual vehicle selected by the driver from the multiple virtual vehicles, and calculates a virtual acceleration of the target virtual vehicle in response to accelerator pedal operation using the target vehicle model based on the accelerator pedal operation state and the electric vehicle driving state. The processing circuit also determines whether the virtual acceleration exceeds the achievable acceleration of the electric vehicle during an acceleration period when the accelerator pedal is depressed. If the processing circuit determines that the virtual acceleration during the acceleration period exceeds the achievable acceleration of the electric vehicle, it executes a correction process that corrects the virtual acceleration so as to modify the time change of the virtual acceleration during the acceleration period in accordance with the amount of excess. The processing circuit then controls the electric motor so that the acceleration of the electric vehicle is the corrected virtual acceleration.

[0010] A second aspect of the present disclosure relates to a control device for an electric vehicle having an electric motor as a drive source, where the electric vehicle is equipped with an accelerator pedal.

[0011] The control device includes a processing circuit and a storage device. The storage device stores a database that manages multiple vehicle models that model multiple virtual vehicles with different acceleration characteristics in response to driving operations by the driver. The processing circuit retrieves from the database a target vehicle model corresponding to a target virtual vehicle selected by the driver from the multiple virtual vehicles, and calculates a virtual acceleration of the target virtual vehicle in response to accelerator pedal operation using the target vehicle model based on the accelerator pedal operation state and the electric vehicle driving state. The processing circuit also determines whether the virtual acceleration exceeds the acceleration achievable by the electric vehicle during an acceleration period when the accelerator pedal is depressed. If the processing circuit determines that the virtual acceleration during the acceleration period exceeds the acceleration achievable by the electric vehicle, it executes a correction process that corrects the virtual acceleration so as to modify the time change of the virtual acceleration during the acceleration period in accordance with the amount of excess. The processing circuit then controls the electric motor so that the acceleration of the electric vehicle is the corrected virtual acceleration. [Effects of the Invention]

[0012] According to the present disclosure, if the virtual acceleration of a target virtual vehicle exceeds the achievable acceleration of the electric vehicle during the acceleration period of the electric vehicle when the accelerator pedal is depressed, the virtual acceleration is corrected so as to modify the time change of the virtual acceleration during the acceleration period according to the amount of the excess. Then, the electric motor is controlled so that the acceleration of the electric vehicle becomes the corrected virtual acceleration. This allows the driver to experience an acceleration sensation equivalent to that of a virtual vehicle having acceleration characteristics that exceed the acceleration capability of the electric vehicle. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a diagram showing a configuration of an electric vehicle according to an embodiment; [Figure 2]FIG. 3 is a tree diagram showing an example of a selection input received by an HMI regarding a control mode of an electric vehicle according to the embodiment. [Figure 3] FIG. 2 is a diagram illustrating an example of a functional configuration of a control device that functions as a motor control device. [Figure 4] FIG. 10 is a diagram showing an example of acceleration characteristics of an electric vehicle achieved when the control mode is an on-demand mode. [Figure 5] FIG. 10 is a diagram showing an example of acceleration characteristics of an electric vehicle that are typically realized when the acceleration characteristics of a target virtual vehicle exceed the acceleration capacity of the electric vehicle. [Figure 6] 4 is a diagram illustrating an example of a functional configuration of an on-demand mode driving force calculation unit illustrated in FIG. 3. FIG. [Figure 7] 7 is a flowchart showing a processing flow of processing executed by a correction determination unit shown in FIG. 6. [Figure 8] 7A and 7B are diagrams illustrating an example of a first specific example of correction processing executed by the correction unit illustrated in FIG. 6. [Figure 9] 7A and 7B are diagrams illustrating an example of a second specific example of correction processing executed by the correction unit illustrated in FIG. 6. [Figure 10] 7A and 7B are diagrams illustrating an example of a third specific example of correction processing executed by the correction unit illustrated in FIG. 6. [Figure 11] 10 is a flowchart showing a processing flow of processing executed by an on-demand mode driving force calculation unit. [Figure 12] FIG. 2 is a diagram illustrating an example of a configuration of a vehicle model. [Figure 13] FIG. 2 is a diagram illustrating an example of a functional configuration of a control device that functions as a sound control device. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In each drawing, the same or corresponding parts are denoted by the same reference numerals, and the description thereof will be simplified or omitted.

[0015] 1. Electric vehicle powertrain configuration 1 is a diagram schematically illustrating the configuration of an electric vehicle 100 according to an embodiment of the present disclosure. First, the configuration of the power system of the electric vehicle 100 will be described with reference to FIG.

[0016] The electric vehicle 100 is equipped with an electric motor (M) 2 as a drive source for traveling. The electric motor 2 is, for example, a three-phase AC motor. An output shaft 3 of the electric motor 2 is connected to one end of a propeller shaft 5 via a gear mechanism 4. The other end of the propeller shaft 5 is connected to a drive shaft 7 at the front of the vehicle via a differential gear 6.

[0017] The electric vehicle 100 has driving wheels 8 which are front wheels and driven wheels 12 which are rear wheels. The driving wheels 8 are provided on both ends of the drive shaft 7, respectively.

[0018] The electric vehicle 100 includes a battery (BATT) 14 and an inverter (INV) 16. The battery 14 stores electrical energy for driving the electric motor 2. In other words, the electric vehicle 100 is a battery electric vehicle (BEV) that runs on electrical energy stored in the battery 14. The inverter 16 is, for example, a voltage-type inverter. The inverter 16 controls the motor torque output by the electric motor 2 by PWM control.

[0019] 2. Electric vehicle control system configuration Next, the configuration of the control system of the electric vehicle 100 will be described with reference to FIG.

[0020] The electric vehicle 100 is equipped with a vehicle speed sensor 30 for detecting vehicle speed. At least one of wheel speed sensors (not shown) provided on each of the left and right front wheels 8 and the left and right rear wheels 12 is used as the vehicle speed sensor 30. The vehicle speed is one of the driving conditions of the electric vehicle 100. The electric vehicle 100 may further be equipped with sensors for detecting other driving conditions of the electric vehicle 100, such as yaw rate, attitude, and the surrounding environment.

[0021] The electric vehicle 100 is equipped with an accelerator pedal stroke sensor 32. The accelerator pedal stroke sensor 32 is provided on the accelerator pedal 22 and outputs a signal indicating the operation state of the accelerator pedal 22. The operation state of the accelerator pedal typically includes the accelerator opening degree and the accelerator opening speed. The electric vehicle 100 is also equipped with a brake pedal stroke sensor 34. The brake pedal stroke sensor 34 is provided on the brake pedal 24 and outputs a signal indicating the operation state of the brake pedal 24. The operation state of the brake pedal 24 typically includes the brake opening degree and the brake opening speed.

[0022] The accelerator pedal 22 and the brake pedal 24 are each one of the driving operation members used to drive the electric vehicle 100. In addition, the electric vehicle 100 may be equipped with various other driving operation members, such as a steering wheel for steering.

[0023] The electric vehicle 100 is equipped with a driving environment detection sensor 35. The driving environment detection sensor 35 is a sensor for detecting the driving environment around the electric vehicle 100. The driving environment detection sensor 35 is composed of a camera, radar, LiDAR, a GNSS (Global Navigation Satellite System) receiver, etc.

[0024] The electric vehicle 100 is equipped with a rotational speed sensor 40. The rotational speed sensor 40 is provided in the electric motor 2 and outputs a signal indicating the rotational speed of the electric motor 2.

[0025] The electric vehicle 100 is equipped with a battery management system (BMS) 10. The battery management system 10 is a device that monitors the cell voltage, current, temperature, etc. of a battery 14. The battery management system 10 has a function of estimating the state of charge (SOC) of the battery 14.

[0026] 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 presents various information to the driver through visual and audio displays and accepts various inputs from the driver. The HMI 20 includes a display (e.g., a multi-information display or a meter display), switches, a touchpad, a speakerphone, a touchscreen, and the like. For example, the HMI 20 displays various information on a display and accepts inputs from the driver regarding the displayed content by operating a switch. For example, the HMI 20 displays various information on a touchscreen and accepts inputs from the driver regarding the displayed content by touching the touchscreen. The in-vehicle speaker 21 is a sound generator that generates artificial sounds within the vehicle cabin. In particular, the in-vehicle speaker 21 can output a pseudo-engine sound, which will be described later. The in-vehicle speaker 21 may be configured as part of the HMI 20.

[0027] The electric vehicle 100 is equipped with a control device 101. Various sensors and devices to be controlled mounted on the electric vehicle 100 are connected to the control device 101 via an in-vehicle network such as a controller area network (CAN). In addition to the vehicle speed sensor 30, accelerator pedal stroke sensor 32, brake pedal stroke sensor 34, and rotational speed sensor 40, various other sensors may be mounted on the electric vehicle 100 and connected to the control device 101 via the in-vehicle network.

[0028] The control device 101 generates control signals related to various controls of the electric vehicle 100 based on signals acquired from each sensor. The control device 101 is typically an electronic control unit (ECU). The control device 101 may be a combination of multiple ECUs. The control device 101 includes at least a processing circuit 102 and a storage device 103.

[0029] The processing circuitry 102 performs various processes. The processing circuitry 102 may be, for example, a general-purpose processor, a special-purpose processor, a central processing unit (CPU), a graphics processing unit (GPU), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), an integrated circuit, a conventional circuit, or a combination of one or more of these. A processor including transistors and other circuits is an example of the processing circuitry 102. The processing circuitry 102 may also be referred to as circuitry or processing circuitry. Circuitry is hardware that is programmed to realize or executes the functions described in this disclosure.

[0030] The storage device 103 stores various information necessary for the processing circuit 102 to execute processing. The storage device 103 is configured with a recording medium such as a RAM (Random Access Memory), a ROM (Read Only Memory), an SSD (Solid State Drive), or an HDD (Hard Disk Drive). The storage device 103 stores a computer program 104 executable by the processing circuit 102 and various data 105. The computer program 104 is configured with a plurality of instructions that describe the processing to be executed by the processing circuit 102. The computer program 104 may be recorded on a computer-readable recording medium. The functions of the control device 101 are realized by cooperation between the processing circuit 102, which executes the computer program 104, and the storage device 103.

[0031] The control device 101 according to this embodiment has at least two control modes, a normal mode and an on-demand mode, for controlling the electric vehicle 100. The control of the electric vehicle 100 performed by the control device 101 changes depending on the selected control mode. The control modes of the electric vehicle 100 will be described below.

[0032] 3 Electric vehicle control modes As described above, there are at least two control modes for the electric vehicle 100: normal mode and on-demand mode. The normal mode is a control mode in which the electric vehicle 100 is operated as a normal BEV. When the normal mode is selected, the control device 101 controls the electric vehicle 100 so that it operates as a normal BEV. On the other hand, the on-demand mode is a control mode in which the electric vehicle 100 reproduces the acceleration feel of a virtual vehicle (hereinafter referred to as the "target virtual vehicle") selected by the driver from among multiple virtual vehicles. When the on-demand mode is selected, the control device 101 controls the electric vehicle 100 so that the driver can obtain a feeling of acceleration as if they were driving the target virtual vehicle. Details of the various controls of the electric vehicle 100 in both the normal mode and the on-demand mode will be described later.

[0033] In the on-demand mode, the multiple virtual vehicles include various vehicles with different acceleration characteristics in response to the driver's driving operations. Each virtual vehicle may be a simulated real vehicle, or may be a fictitious vehicle. Differences in acceleration characteristics are generally due to differences in the configuration of the powertrain from the drive source to the drive wheels or differences in the powertrain control method. Therefore, the multiple virtual vehicles can be considered to include various vehicles with different powertrain-related configurations or control methods at least in part.

[0034] The control mode is selected by the driver operating the HMI 20. The HMI 20 is configured to receive a control mode selection input from the driver. Furthermore, for the on-demand mode, the HMI 20 is configured to receive a target virtual vehicle selection input from the driver.

[0035] 2 is a tree diagram showing an example of a selection input received by the HMI 20. For example, the HMI 20 receives a selection input from the driver via a display or a touch screen in accordance with the tree shown in FIG. 2 as follows:

[0036] First, the HMI 20 displays a setting menu screen on the display or touch screen in accordance with the driver's operation. The initial screen of the setting menu screen displays the options "Control Mode" and "Target Virtual Vehicle". The option "Control Mode" is an option for accepting a selection input of the control mode from the driver. The option "Target Virtual Vehicle" is an option for accepting a selection input of the target virtual vehicle from the driver.

[0037] When the option "control mode" is selected, the options "normal mode" and "on-demand mode" are then displayed on the settings menu screen. When the option "normal mode" is selected, the HMI 20 determines that the control mode of the electric vehicle 100 is the normal mode. When the option "on-demand mode" is selected, the HMI 20 determines that the control mode of the electric vehicle 100 is the on-demand mode. In this way, the HMI 20 accepts the control mode selection input from the driver.

[0038] On the other hand, when the option "on-demand mode" is selected, the settings menu screen then displays options "CONV" and "HEV." The options "CONV" and "HEV" each indicate a classification of multiple virtual vehicles that can be selected in on-demand mode. CONV is a classification that indicates a conventional internal combustion engine vehicle. HEV is a classification that indicates a hybrid electric vehicle. When the option "CONV" is selected, the settings menu screen then displays options "virtual vehicle A1," "virtual vehicle A2," and "virtual vehicle B1." Virtual vehicle A1, virtual vehicle A2, and virtual vehicle B1 are virtual vehicles classified as CONV among the multiple selectable virtual vehicles. Similarly, when the option "HEV" is selected, the settings menu screen then displays options "virtual vehicle C1" and "virtual vehicle C2." Virtual vehicle C1 and virtual vehicle C2 are virtual vehicles classified as HEV among the multiple selectable virtual vehicles. When one of these options is selected, the HMI 20 determines the corresponding virtual vehicle as the target virtual vehicle. For example, when the option "Virtual Vehicle A2" is selected, the HMI 20 determines the virtual vehicle A2 as the target virtual vehicle. In this way, the HMI 20 receives a selection input of the target virtual vehicle from the driver.

[0039] The classification of the multiple virtual vehicles in the above description is an example, and the options related to the classification may be changed as appropriate. For example, the options related to the classification may further include an option indicating a plug-in hybrid electric vehicle or a fuel cell electric vehicle. Furthermore, for example, the options related to the classification may indicate other classifications, such as a classification related to the type of internal combustion engine installed (e.g., a supercharged inline-four engine, a flat-six engine, a V12 engine). Alternatively, when the option "on-demand mode" is selected, options related to the virtual vehicle may be displayed without displaying options related to the classification.

[0040] The name displayed on the setting menu screen for each option may be set appropriately in consideration of ease of understanding by the driver. For example, for an option related to a virtual vehicle, the displayed name may be a more specific name, such as the model name or product name, that allows the driver to easily imagine the virtual vehicle.

[0041] As described above, the driver can select a control mode by operating the HMI 20. The control device 101 controls the electric vehicle 100 according to the selected control mode.

[0042] The control device 101 according to this embodiment functions as a motor control device that controls the electric motor 2 in accordance with at least the driver's driving operation with respect to the control of the electric vehicle 100. More specifically, the processing circuit 102 executes a computer program 104 for electric motor control stored in a storage device 103, causing the control device 101 to function as a motor control device. The electric motor 2 is the drive source of the electric vehicle 100. Therefore, the motor control device can also be said to be a device that controls the drive of the electric vehicle 100. The control of the electric vehicle 100 by the motor control device will be described below.

[0043] 4 Motor control device 3 is a diagram showing an example of the functional configuration of the motor control device 101a. The motor control device 101a calculates a target driving force for the electric vehicle 100 in response to the driver's driving operation. The motor control device 101a then controls the electric motor 2 via the inverter 16 so as to apply the calculated target driving force to the electric vehicle 100.

[0044] Signals from the HMI 20 and the sensor system 50 are input to the motor control device 101a. The sensor system 50 includes a vehicle speed sensor 30, an accelerator pedal stroke sensor 32, a brake pedal stroke sensor 34, a driving environment detection sensor 35, a rotational speed sensor 40, and a battery management system 10. The sensor system 50 may also include other sensors not shown. For example, the sensor system 50 may include a steering angle sensor for detecting the steering angle of the steering wheel, a yaw rate sensor for detecting the yaw rate of the electric vehicle 100, an IMU (Inertial Measurement Unit) for detecting the attitude of the electric vehicle 100, a sensor for detecting the ambient environment of the electric vehicle 100 (e.g., a camera, radar, LiDAR), etc.

[0045] The signals input from the HMI 20 to the motor control device 101a include a signal indicating the control mode selected by the driver and a signal indicating the target virtual vehicle selected by the driver. The signals input from the sensor system 50 to the motor control device 101a include a signal indicating the vehicle speed of the electric vehicle 100, a signal indicating the operation state of the accelerator pedal 22, a signal indicating the operation state of the brake pedal 24, a signal indicating the driving environment of the electric vehicle 100, a signal indicating the rotational speed of the electric motor 2, and a signal indicating the state of the battery 14 (e.g., cell voltage, current, temperature, SOC).

[0046] The motor control device 101a includes, as functional blocks, a mode information acquisition unit 110, an on-demand mode driving force calculation unit 120, a normal mode driving force calculation unit 130, a target driving force switching unit 140, and an electric motor control unit 150. These functional blocks are realized by cooperation between a processing circuit 102 that executes a computer program 104 and a storage device 103.

[0047] The mode information acquisition unit 110 receives a signal from the HMI 20 and acquires information regarding whether the normal mode or the on-demand mode has been selected. The mode information acquisition unit 110 also acquires information regarding the target virtual vehicle selected by the driver. The mode information acquisition unit 110 transmits information regarding the selected control mode to the target driving force switching unit 140. The mode information acquisition unit 110 also transmits information regarding the selected target virtual vehicle to the on-demand mode driving force calculation unit 120.

[0048] The on-demand mode driving force calculation unit 120 acquires information about the target virtual vehicle selected by the driver from the mode information acquisition unit 110. Then, the on-demand mode driving force calculation unit 120 calculates a target driving force for the on-demand mode based on signals from the sensor system 50. In other words, the on-demand mode driving force calculation unit 120 calculates a target driving force for reproducing, in the electric vehicle 100, the acceleration feeling of the target virtual vehicle in response to the driving operation of the driver. Details of the processing executed by the on-demand mode driving force calculation unit 120 will be described later.

[0049] The normal mode driving force calculation unit 130 calculates the target driving force for the normal mode based on signals from the sensor system 50. That is, the normal mode driving force calculation unit 130 calculates the target driving force for operating the electric vehicle 100 as a normal BEV. For example, the normal mode driving force calculation unit 130 calculates the target driving force using a map that uses the accelerator opening of the accelerator pedal 22 and the rotational speed of the electric motor 2 as parameters. Furthermore, the normal mode driving force calculation unit 130 may be configured to calculate the target driving force using the brake opening of the brake pedal 24 or the SOC of the battery 14 as parameters. However, in this embodiment, the processing performed by the normal mode driving force calculation unit 130 is not particularly limited. The processing performed by the normal mode driving force calculation unit 130 may also apply other suitable known techniques.

[0050] The target driving force switching unit 140 switches the target driving force of the electric vehicle 100 used to control the electric motor 2 according to the selected control mode. The target driving force switching unit 140 acquires information on the selected control mode from the mode information acquisition unit 110. When the on-demand mode is selected, the target driving force switching unit 140 transmits the target driving force calculated by the on-demand mode driving force calculation unit 120 to the electric motor control unit 150 as the target driving force of the electric vehicle 100. On the other hand, when the normal mode is selected, the target driving force switching unit 140 transmits the target driving force calculated by the normal mode driving force calculation unit 130 to the electric motor control unit 150 as the target driving force of the electric vehicle 100.

[0051] Note that when the on-demand mode is selected, the normal mode driving force calculation unit 130 may be configured not to execute any processing. Similarly, when the normal mode is selected, the on-demand mode driving force calculation unit 120 may be configured not to execute any processing.

[0052] The target driving force of the electric vehicle 100 is input to the electric motor control unit 150 via the target driving force switching unit 140. That is, when the on-demand mode is selected, the target driving force calculated by the on-demand mode driving force calculation unit 120 is input to the electric motor control unit 150. On the other hand, when the normal mode is selected, the target driving force calculated by the normal mode driving force calculation unit 130 is input to the electric motor control unit 150. The electric motor control unit 150 changes the motor torque output by the electric motor 2 so as to apply the input target driving force to the electric vehicle 100. More specifically, the electric motor control unit 150 generates a control signal for the inverter 16 in accordance with the input target driving force. Then, the electric motor control unit 150 changes the motor torque output by the electric motor 2 via PWM control by the inverter 16.

[0053] In this way, the motor control device 101a controls the electric motor 2 to apply a target driving force corresponding to the control mode to the electric vehicle 100. Therefore, according to the motor control device 101a, when the on-demand mode is selected, the acceleration characteristics of the electric vehicle 100 are acceleration characteristics that simulate the acceleration characteristics of the target virtual vehicle selected by the driver. On the other hand, when the normal mode is selected, the acceleration characteristics of the electric vehicle 100 are the acceleration characteristics of a normal BEV.

[0054] FIG. 4 is a diagram showing an example of the acceleration characteristic VAC of the electric vehicle 100 when the on-demand mode is selected. For comparison, FIG. 4 also shows the acceleration characteristic of a normal BEV (dashed line). When the on-demand mode is selected, the acceleration characteristic VAC of the electric vehicle 100 changes to various patterns depending on the target virtual vehicle as the target virtual vehicle is changed. This is because the target driving force calculated in the on-demand mode changes depending on the target virtual vehicle selected by the driver. As a result, in the on-demand mode, the driver can enjoy the acceleration sensation of various virtual vehicles in the electric vehicle 100.

[0055] The calculation of the target driving force in the on-demand mode, that is, the processing executed by the on-demand mode driving force calculation unit 120, will be described in detail below.

[0056] 4.1 Calculation of target driving force in on-demand mode The on-demand mode driving force calculation unit 120 calculates the target driving force so that the acceleration feeling of the target virtual vehicle in response to the driver's driving operation is reproduced in the electric vehicle 100. In particular, the on-demand mode driving force calculation unit 120 uses a vehicle model of the target virtual vehicle (hereinafter referred to as the "target vehicle model") to calculate (simulate) the virtual acceleration when the target virtual vehicle is driven, and employs a method (hereinafter referred to as the "virtual acceleration-based method") of calculating the target driving force so that the acceleration of the electric vehicle 100 becomes the virtual acceleration.

[0057] However, the acceleration that can be achieved by the electric vehicle 100, i.e., the acceleration capacity of the electric vehicle 100, is naturally limited in relation to the motor torque output characteristics of the electric motor 2. In particular, the acceleration capacity of the electric vehicle 100 is equivalent to the acceleration characteristics of a normal BEV. In other words, the acceleration characteristics that can be achieved by the electric vehicle 100 are within the range of the acceleration characteristics of a normal BEV.

[0058] For this reason, with the virtual acceleration-based method, if the acceleration characteristics of the target virtual vehicle exceed the acceleration capacity of the electric vehicle 100, a situation may arise in which the acceleration characteristics of the target virtual vehicle cannot be realized as is in the electric vehicle 100. FIG. 5 is a diagram showing an example of the acceleration characteristics VAC of the electric vehicle 100 that are realized when the acceleration characteristics of the target virtual vehicle exceed the acceleration capacity of the electric vehicle 100. In the example shown in FIG. 5, the acceleration characteristics VAC of the electric vehicle 100 cannot realize the acceleration characteristics of the target virtual vehicle (dashed line) as is because they are limited by the acceleration capacity of the electric vehicle 100 (dash-dotted line). Therefore, in this case, there is a possibility that the acceleration realized by the electric vehicle 100 in response to operation of the accelerator pedal 22 will be smaller than the virtual acceleration of the target virtual vehicle that should be realized.

[0059] On the other hand, the sense of acceleration felt by the driver when accelerating electric vehicle 100 varies not only depending on the actual acceleration but also on the shape of the change in acceleration over time after accelerator pedal 22 is depressed. By appropriately modifying the change in acceleration over time based on the characteristics of the driver's perception of the sense of acceleration, the sense of acceleration felt by the driver can be made stronger relative to the actual acceleration. For example, the greater the jerk when acceleration increases, the stronger the sense of acceleration felt by the driver.

[0060] Based on the above viewpoint, the on-demand mode driving force calculation unit 120 according to this embodiment is configured to enable the driver to experience a sense of acceleration equivalent to that of the target virtual vehicle, even when the acceleration characteristics of the target virtual vehicle exceed the acceleration capacity of the electric vehicle 100. In other words, the on-demand mode driving force calculation unit 120 modifies the time change in the realized acceleration so as to enhance the sense of acceleration felt by the driver, based on the difference between the acceleration realized by the electric vehicle 100 and the virtual acceleration of the target virtual vehicle that should be realized.

[0061] 6 is a diagram showing an example of the functional configuration of the on-demand mode driving force calculation unit 120. The on-demand mode driving force calculation unit 120 includes, as functional blocks, a virtual acceleration calculation unit 121, a driving scene determination unit 122, a correction determination unit 123, a correction unit 124, and a target driving force calculation unit 125. The on-demand mode driving force calculation unit 120 is also configured to be able to access the vehicle model database D10.

[0062] The vehicle model database D10 is a database that manages multiple vehicle models 200 that are models of multiple virtual vehicles. The vehicle model database D10 may be realized as data 105 stored in the storage device 103. New vehicle models 200 may be downloaded to the vehicle model database D10 as needed. In the example shown in FIG. 6 , the vehicle model database D10 manages three vehicle models 200-A, 200-B, and 200-C. Each vehicle model 200 is a model that simulates the behavior of a virtual vehicle in response to a driving operation by a driver, using the operation state AS of the accelerator pedal 22 and the running state RS of the electric vehicle 100 as input. Each vehicle model 200 is configured to be able to simulate at least the driving force applied to the virtual vehicle in response to a driving operation, particularly the operation of the accelerator pedal 22, and the acceleration and deceleration behavior of the virtual vehicle resulting from the application of that driving force. The simulation results of the acceleration and deceleration behavior of the virtual vehicle in each vehicle model 200 include the virtual acceleration of the virtual vehicle. That is, each vehicle model 200 is configured to be able to calculate the virtual acceleration of the virtual vehicle in response to the driving operation of the driver.

[0063] Typically, each vehicle model 200 is composed of a control model that simulates a control system related to the powertrain of the virtual vehicle, and a plant model that simulates the acceleration and deceleration behavior of the virtual vehicle in response to control signals from the control model. In this case, the plant model includes a model of the powertrain that operates based on control signals from the control model, and a model for simulating the behavior of the virtual vehicle due to the action of the virtual driving force output by the powertrain model. An example of the configuration of vehicle model 200 will be described later.

[0064] Each vehicle model 200 also has parameters 201 related to the operation of the virtual vehicle in the simulation. Examples of the parameters 201 include vehicle weight, tire diameter, each gear ratio, maximum engine torque, engine torque responsiveness, and gear shift timing. The contents of the parameters 201 may differ for each vehicle model 200. The vehicle model 200 expresses a model of one virtual vehicle by combining it with the setting values ​​of its parameters 201. For example, each virtual vehicle corresponds to a combination of the vehicle model 200 and the setting values ​​of the parameters 201, as shown in the table below. As shown in the table below, the same vehicle model 200 may correspond to different virtual vehicles. This is the case when the powertrain systems are the same type and each virtual vehicle can be expressed by changing the setting values ​​of the parameters 201. [Table 1]

[0065] The virtual acceleration calculation unit 121 acquires information about the target virtual vehicle STV selected by the driver from the mode information acquisition unit 110. Then, the virtual acceleration calculation unit 121 references the vehicle model database D10 and reads out the vehicle model 200 (target vehicle model) corresponding to the target virtual vehicle STV. The example shown in FIG. 6 shows a case where the virtual acceleration calculation unit 121 reads out the vehicle model 200-B. Furthermore, the virtual acceleration calculation unit 121 sets the parameter 201 of the read vehicle model 200 in accordance with the target virtual vehicle STV. For example, when the target virtual vehicle STV is "virtual vehicle B1" in the above table, the virtual acceleration calculation unit 121 sets the parameter 201-B of the vehicle model 200-B to the setting value B1.

[0066] The virtual acceleration calculation unit 121 uses the read target vehicle model to calculate a virtual acceleration VG of the target virtual vehicle STV in response to operation of the accelerator pedal 22. More specifically, the virtual acceleration calculation unit 121 receives signals from the sensor system 50 and acquires information on the operation state AS of the accelerator pedal 22 (e.g., accelerator opening) and information on the running state RS of the electric vehicle 100 (e.g., vehicle speed) to be input to the target vehicle model. In addition, depending on the configuration of the target vehicle model, the virtual acceleration calculation unit 121 may acquire information such as the operation state of the brake pedal 24, the steering angle of the steering wheel, and the yaw rate of the electric vehicle 100. The virtual acceleration calculation unit 121 inputs the acquired information to the target vehicle model. Then, the virtual acceleration calculation unit 121 calculates the virtual acceleration VG of the target virtual vehicle STV by simulating the acceleration and deceleration operation of the target virtual vehicle STV using the target vehicle model. The virtual acceleration VG calculated by the virtual acceleration calculation unit 121 is transmitted to the correction unit 124.

[0067] The driving scene determination unit 122 acquires driving environment information TEI from the sensor system 50. The driving environment information TEI indicates information about the driving environment around the electric vehicle 100. The driving environment information TEI is typically information detected by the driving environment detection sensor 35. The driving environment information TEI may include map information around the electric vehicle 100, road traffic information, road shape information, etc. The driving scene determination unit 122 recognizes at least the driving environment ahead of the electric vehicle 100 based on the driving environment information TEI. For example, the driving scene determination unit 122 recognizes the status of other vehicles ahead, the curvature and width of the road extending ahead, the status of traffic lights ahead, etc.

[0068] Furthermore, based on the recognized driving environment, the driving scene determination unit 122 determines a driving scene related to the acceleration of the electric vehicle 100. For example, the driving scene determination unit 122 determines whether the driving scene of the electric vehicle 100 is "there is / is not a vehicle ahead," "a sharp curve / a straight road," "the road is narrow / wide," "the traffic light ahead is red / green," etc.

[0069] The traveling scene determination unit 122 then sets a scene determination flag SF to 1 or 0 depending on the determined traveling scene. More specifically, the traveling scene determination unit 122 sets the scene determination flag SF to 1 when the determined traveling scene is one in which it is expected that the driver will continuously accelerate the electric vehicle 100 for a certain period of time. For example, the traveling scene determination unit 122 sets the scene determination flag SF to 1 when the determined traveling scene is "no vehicle ahead," "straight road," "wide road," "green traffic light ahead," etc. On the other hand, the traveling scene determination unit 122 sets the scene determination flag to 0 when the determined traveling scene is "vehicle ahead," "sharp curve," "narrow road," "red traffic light ahead," etc. The scene determination flag SF indicates whether or not the correction unit 124, which will be described later, should correct the virtual acceleration VG for the traveling scene. The scene determination flag SF set by the traveling scene determination unit 122 is transmitted to the correction determination unit 123.

[0070] When the driver depresses the accelerator pedal 22 to accelerate the electric vehicle 100, the correction determination unit 123 determines whether or not to perform a correction of the virtual acceleration VG by the correction unit 124, which will be described later.

[0071] FIG. 7 is a flowchart showing the processing flow of the processing executed by the correction determination unit 123.

[0072] In step S100, the correction determination unit 123 acquires information about the target virtual vehicle STV from the mode information acquisition unit 110. The correction determination unit 123 also acquires information about the operation state AS of the accelerator pedal 22 and information about the driving state RS of the electric vehicle 100 from the sensor system 50. The correction determination unit 123 also acquires a scene determination flag SF from the driving scene determination unit 122.

[0073] The correction determination unit 123 manages the acceleration characteristics of each of the multiple virtual vehicles that can be selected in the on-demand mode. The correction determination unit 123 can refer to the acceleration characteristics of the target virtual vehicle STV based on the information of the target virtual vehicle STV acquired from the mode information acquisition unit 110. The correction determination unit 123 also manages the acceleration characteristics of the electric vehicle 100 as a normal BEV (the acceleration capability of the electric vehicle 100).

[0074] In step S110, the correction determination unit 123 determines whether the accelerator pedal 22 has been depressed based on the operation state AS. For example, the correction determination unit 123 determines that the accelerator pedal 22 has been depressed when the accelerator opening and the amount of change in the accelerator opening are equal to or greater than predetermined threshold values.

[0075] If it is determined that the accelerator pedal 22 is depressed (step S110; Yes), the process proceeds to step S120. If it is determined that the accelerator pedal 22 is not depressed (step S110; No), the correction determination unit 123 determines not to perform correction (step S150), and ends the process.

[0076] In step S120, the correction determination unit 123 determines whether the scene determination flag is 1. If the scene determination flag is 1 (step S110; Yes), the process proceeds to step S130. If the scene determination flag is 0 (step S110; No), the correction determination unit 123 determines not to perform correction (step S150), and ends the process.

[0077] When the scene determination flag is 0, even if the accelerator pedal 22 is depressed, it is expected that the driver will immediately release the accelerator pedal 22 to stop the acceleration of the electric vehicle 100. In such a case, the correction determination unit 123 performs the process in step S120 to prevent the correction unit 124 from correcting the virtual acceleration VG. This makes it possible to prevent unnecessary correction of the virtual acceleration VG and a deterioration in drivability.

[0078] In step S130, the correction determination unit 123 determines whether or not the virtual acceleration VG exceeds the acceleration that can be achieved by the electric vehicle 100 during the acceleration period in which the accelerator pedal 22 is depressed and the electric vehicle 100 accelerates. In other words, the correction determination unit 123 determines whether or not the acceleration achieved by the electric vehicle 100 in response to the operation of the accelerator pedal 22 during the acceleration period is smaller than the virtual acceleration VG that should be achieved.

[0079] The correction determination unit 123 can acquire the achievable acceleration from the accelerator opening and vehicle speed by referring to the acceleration characteristics of a normal BEV. Also, the correction determination unit 123 can determine whether the virtual acceleration VG exceeds the achievable acceleration during the acceleration period from the accelerator opening and vehicle speed by referring to the acceleration characteristics of the target virtual vehicle STV.

[0080] If the virtual acceleration VG exceeds the achievable acceleration during the acceleration period (step S130; Yes), the correction determination unit 123 determines to perform correction (step S140) and terminates the process. On the other hand, if the virtual acceleration VG does not exceed the achievable acceleration during the acceleration period (step S130; No), the correction determination unit 123 determines not to perform correction (step S150) and terminates the process.

[0081] As described above, the correction determination unit 123 executes processing to determine whether or not to correct the virtual acceleration VG by the correction unit 124. Referring again to FIG. 6, the correction unit 124 transmits the determination result JR to the correction unit 124. The determination result JR includes information on whether or not to perform correction. If it is determined that correction should be performed, the determination result JR further includes information on the excess amount of the virtual acceleration VG during the acceleration period relative to the achievable acceleration. The excess amount indicates the difference between the acceleration achieved by the electric vehicle 100 in response to the operation of the accelerator pedal 22 and the virtual acceleration VG that should be achieved.

[0082] The correction unit 124 acquires the virtual acceleration VG from the virtual acceleration calculation unit 121. Upon receiving the determination result JR indicating that a correction should be performed, the correction unit 124 executes a correction process to correct the virtual acceleration VG. In the correction process, the correction unit 124 corrects the virtual acceleration VG so as to modify the time change of the virtual acceleration VG during the acceleration period in accordance with the excess amount indicated by the determination result JR. The correction unit 124 transmits the virtual acceleration CVG corrected by executing the correction process to the target driving force calculation unit 125.

[0083] The correction process is executed to compensate for the excess amount by increasing the acceleration sensation felt by the driver by modifying the time change of the virtual acceleration VG during the acceleration period. The following first to third specific examples can be adopted as such a correction process.

[0084] In a first example of the correction process, the virtual acceleration VG is corrected so that the jerk when the virtual acceleration increases during the acceleration period becomes larger than before the correction. This takes advantage of the driver's cognitive characteristics, that is, the greater the jerk when the acceleration increases, the stronger the acceleration sensation felt by the driver.

[0085] FIG. 8 is a diagram illustrating an example of a correction process according to a first specific example. FIG. 8 illustrates time variations in the accelerator pedal position, virtual acceleration VG, and corrected virtual acceleration CVG. In the example illustrated in FIG. 8, the accelerator pedal 22 is depressed between time t1 and time t2. The virtual acceleration VG begins to increase at time t3, exceeds the achievable acceleration, and reaches a value corresponding to the accelerator pedal position. Compared to this virtual acceleration VG, the corrected virtual acceleration CVG does not exceed the achievable acceleration, but exhibits a larger jerk when rising. The correction process according to the first specific example corrects the virtual acceleration VG as shown in FIG. 8 to calculate the corrected virtual acceleration CVG. The correction process according to the first specific example may be configured to determine the degree to which the jerk is increased depending on the excess amount in order to compensate for the excess amount. In this way, the correction process according to the first specific example allows the corrected virtual acceleration CVG to achieve an acceleration feeling equivalent to that of the uncorrected virtual acceleration VG.

[0086] A second example of the correction process is to correct the virtual acceleration VG so that it temporarily decreases before increasing during the acceleration period. This takes advantage of the driver's cognitive characteristics, namely, the greater the change in acceleration, the stronger the driver's sense of acceleration.

[0087] FIG. 9 is a diagram illustrating an example of a correction process according to a second specific example. In FIG. 9, the accelerator opening and the virtual acceleration VG change over time in the same manner as in FIG. 8. The corrected virtual acceleration CVG shown in FIG. 9 does not exceed the achievable acceleration of the virtual acceleration VG, but temporarily decreases before increasing (between time t2 and time t3). The correction process according to the second specific example corrects the virtual acceleration VG as shown in FIG. 9 to calculate the corrected virtual acceleration CVG. The correction process according to the second specific example may be configured to determine the degree to which the virtual acceleration is decreased in accordance with the excess amount in order to compensate for the excess amount. In this way, the correction process according to the second specific example allows the corrected virtual acceleration CVG to achieve a feeling of acceleration equivalent to that of the pre-correction virtual acceleration VG.

[0088] A third example of the correction process is to correct the virtual acceleration VG so that the time it takes for the virtual acceleration to increase during the acceleration period becomes shorter than before the correction. This takes advantage of the driver's cognitive characteristics, that is, the faster the acceleration starts to increase, the stronger the driver feels the acceleration.

[0089] FIG. 10 is a diagram illustrating an example of a correction process according to a third specific example. In FIG. 10, the accelerator opening and the virtual acceleration VG change over time in the same manner as in FIG. 8. The corrected virtual acceleration CVG shown in FIG. 10 does not exceed the achievable acceleration of the virtual acceleration VG, but the time it takes to increase is shorter. The correction process according to the third specific example corrects the virtual acceleration VG as shown in FIG. 10 to calculate the corrected virtual acceleration CVG. The correction process according to the third specific example may be configured to determine the time it takes for the virtual acceleration to increase in accordance with the excess amount in order to compensate for the excess amount. In this way, the correction process according to the third specific example allows the corrected virtual acceleration CVG to achieve a feeling of acceleration equivalent to that of the uncorrected virtual acceleration VG.

[0090] The first to third specific examples described above can be combined. For example, the first specific example and the second specific example may be combined to execute the correction process. In this case, the correction process may be configured to determine the degree to which the virtual acceleration is reduced and the time until the virtual acceleration increases depending on the excess amount.

[0091] As described above, the correction unit 124 executes the correction process to correct the virtual acceleration VG and transmits the corrected virtual acceleration CVG to the target driving force calculation unit 125. Note that the correction unit 124 does not execute the correction process when it receives a determination result JR indicating that correction is not to be performed. In this case, the corrected virtual acceleration CVG is equivalent to the uncorrected virtual acceleration VG.

[0092] Referring again to Figure 6, the target driving force calculation unit 125 acquires the corrected virtual acceleration CVG from the correction unit 124 and calculates a target driving force for converting the acceleration of the electric vehicle 100 into the virtual acceleration CVG. For example, the target driving force calculation unit 125 converts the virtual acceleration CVG into the target driving force F using a simple inverse model of the electric vehicle 100, as shown in the following equation: veh In the following formula, m is the weight of 100 electric vehicles, F load is the actual running resistance applied to the electric vehicle 100. The on-demand mode driving force calculation unit 120 outputs the target driving force calculated by the target driving force calculation unit 125.

number

[0093] In this way, the functional configuration of the on-demand mode driving force calculation unit 120 according to this embodiment can be provided. Fig. 11 is a flowchart showing the processing flow of the processing executed by the on-demand mode driving force calculation unit 120 based on the above-described functional configuration. The processing flow shown in Fig. 11 is repeatedly executed at a predetermined processing cycle.

[0094] In step S200, the on-demand mode driving force calculation unit 120 acquires various information. For example, the on-demand mode driving force calculation unit 120 acquires information about the target virtual vehicle STV from the mode information acquisition unit 110. The on-demand mode driving force calculation unit 120 also acquires information about the operation state AS of the accelerator pedal 22 and information about the driving state RS of the electric vehicle 100 from the sensor system 50.

[0095] Next, in step S210, the on-demand mode driving force calculation unit 120 refers to the vehicle model database D10 and reads out the vehicle model 200 (target vehicle model) corresponding to the target virtual vehicle STV.

[0096] Next, in step S220, the on-demand mode driving force calculation unit 120 calculates the virtual acceleration VG of the target virtual vehicle in response to the operation of the accelerator pedal 22 using the target vehicle model.

[0097] Next, in step S230, on-demand mode driving force calculation unit 120 determines whether or not to correct virtual acceleration VG. Whether or not to correct is determined by correction determination unit 123. If correction is to be performed (step S230; Yes), the virtual acceleration VG is corrected (step S230), and then processing proceeds to step S230. If correction is not to be performed (step S230; No), the virtual acceleration VG is not corrected, and processing proceeds to step S240.

[0098] Next, in step S240, the on-demand mode driving force calculation unit 120 calculates a target driving force for setting the acceleration of the electric vehicle 100 to the virtual acceleration CVG, after which the current processing ends.

[0099] As described above, according to this embodiment, when the virtual acceleration VG exceeds the achievable acceleration of the electric vehicle 100 during an acceleration period of the electric vehicle 100, the virtual acceleration VG is corrected so as to modify the time change of the virtual acceleration VG during the acceleration period according to the amount of excess. The corrected virtual acceleration CVG achieves an acceleration feel equivalent to that of the pre-correction virtual acceleration VG. Furthermore, according to this embodiment, a target driving force is calculated to make the acceleration of the electric vehicle 100 equal to the virtual acceleration CVG. This allows the driver to experience an acceleration feel equivalent to that of the target virtual vehicle, even when the acceleration characteristics of the target virtual vehicle exceed the acceleration capacity of the electric vehicle 100. Furthermore, it is possible to increase the variety of virtual vehicles that can reproduce the acceleration feel in on-demand mode, thereby improving user satisfaction.

[0100] 4.1.2 Vehicle model configuration example Here, an example of the configuration of vehicle model 200 managed by vehicle model database D10 will be described. FIG. 12 is a diagram showing an example of the configuration of vehicle model 200. Vehicle model 200 includes control model 210 and plant model 220. Control model 210 simulates a control system related to the powertrain of a virtual vehicle. Plant model 220 simulates the acceleration and deceleration operation of the virtual vehicle in response to control signals from control model 210. Plant model 220 includes a model of the powertrain that operates based on the control signals from control model 210, and a model for simulating the operation of the virtual vehicle due to the action of a virtual driving force output by the powertrain model. Control model 210 can also be said to simulate a control system that calculates the required output of the powertrain of the virtual vehicle. Furthermore, plant model 220 can also be said to simulate physical constraints on the required output of the powertrain.

[0101] The specifications of the control model 210 and the plant model 220 differ depending on the type of powertrain system. For example, the configurations of the control system, transmission, and drivetrain differ between a CONV and an HEV. Therefore, the CONV vehicle model 200 and the HEV vehicle model 200 have different specifications for both the control model 210 and the plant model 220. The example shown in FIG. 12 particularly illustrates a case where the virtual vehicle is an automatic transmission vehicle (AT vehicle) equipped with an internal combustion engine.

[0102] The control model 210 includes a target virtual driving force calculation unit 211 and a required output calculation unit 212. The target virtual driving force calculation unit 211 calculates a virtual driving force (target virtual driving force) required from the output of the powertrain of the virtual vehicle based on the accelerator opening and vehicle speed. For example, the target virtual driving force calculation unit 211 performs calculations using a map that assigns a target virtual driving force to a combination of accelerator opening and vehicle speed. The required output calculation unit 212 calculates a required output for the powertrain so as to satisfy the calculated target virtual driving force. The calculated required output includes a target engine torque of the internal combustion engine and a target gear position of the transmission. The control model 210 transmits the calculated required output to the plant model 220.

[0103] The plant model 220 includes an internal combustion engine model 221, a transmission model 222, a drivetrain model 223, and a vehicle and environment model 224. The internal combustion engine model 221, the transmission model 222, and the drivetrain model 223 are models of the powertrain from the drive source to the drive wheels. The vehicle and environment model 224 is a model for simulating the operation of a virtual vehicle due to the action of a virtual driving force output by the powertrain model.

[0104] The internal combustion engine model 221 is a model of the internal combustion engine of the virtual vehicle. The internal combustion engine model 221 simulates the operation of the internal combustion engine in response to an input of a target engine torque, for example. The internal combustion engine model 221 outputs a virtual engine speed and a virtual engine torque. In the internal combustion engine model 221, parameters 201 that can be changed depending on the target virtual vehicle include, for example, the maximum engine torque and the engine torque responsiveness.

[0105] The transmission model 222 is a model of the transmission of the virtual vehicle. The transmission model 222 simulates the operation of the transmission in response to, for example, the input of a target gear. The transmission model 222 outputs a virtual transmission output torque from the virtual engine torque output by the internal combustion engine model 221 and a gear ratio determined by the virtual gear. The transmission model 222 includes a stepped transmission model that simulates a stepped transmission, and a continuously variable transmission model that simulates a continuously variable transmission. Either the stepped transmission model or the continuously variable transmission model is selected depending on the target virtual vehicle. In the transmission model 222, parameters 201 that can be changed depending on the target virtual vehicle include, for example, each gear ratio, gear shift timing, etc. In the case of a stepped transmission model, the gear ratio means the gear ratio of each gear.

[0106] The drivetrain model 223 is a model of the drivetrain of the virtual vehicle. For example, the drivetrain model 223 models the mechanical structure from the transmission to the drive wheels. The drivetrain model 223 calculates the drivewheel torque using the virtual transmission output torque output by the transmission model 222 and a predetermined reduction ratio, and outputs the virtual drive force of the virtual vehicle. In the drivetrain model 223, parameters 201 that can be changed depending on the target virtual vehicle include, for example, the reduction ratio, the maximum allowable torque of the propeller shaft, etc.

[0107] The vehicle and environment model 224 is a model that represents the dynamic characteristics of the virtual vehicle and the driving environment of the virtual vehicle. The vehicle and environment model 224 calculates the running resistance acting on the virtual vehicle from the driving environment of the virtual vehicle. The vehicle and environment model 224 then simulates the acceleration and deceleration of the virtual vehicle from the virtual driving force output from the drivetrain model 223, the calculated running resistance, and the dynamic characteristics of the virtual vehicle. The vehicle and environment model 224 outputs virtual acceleration from the acceleration and deceleration of the virtual vehicle. Parameters 201 that can be changed in the vehicle and environment model 224 depending on the target virtual vehicle include, for example, vehicle weight, tire diameter, CD value, etc.

[0108] As described above, vehicle model 200 can be configured. Vehicle model 200 shown in FIG. 4 is an example. Vehicle model 200 can also be configured in more detail depending on the event to be emphasized. For example, consider a case where it is desired to emphasize the shock or response associated with the shifting of the transmission gear and clutch during kickdown. In this case, transmission model 222 may be configured to precisely reproduce the gear mechanism of the transmission, such as a planetary gearbox or a ravigneaux gearbox, the inertia of each component, and changes in the transmission path when the clutch is engaged and disengaged. On the other hand, if it is desired to reduce the computational load on vehicle model 200, transmission model 222 may be simply configured to reproduce only the gear ratio.

[0109] 5. Sound Control Device The control device 101 according to this embodiment may function as a sound control device that controls the in-vehicle speaker 21 to output a pseudo engine sound corresponding to a target virtual vehicle in relation to the control of the electric vehicle 100. More specifically, the processing circuit 102 executes a computer program 104 for controlling the in-vehicle speaker stored in the storage device 103, causing the control device 101 to function as a sound control device. The control of the electric vehicle 100 by the sound control device will be described below.

[0110] 13 is a diagram showing the functional configuration of the sound control device 101b. The sound control device 101b generates from the in-vehicle speaker 21 a pseudo engine sound that simulates the engine sound of a virtual vehicle equipped with an internal combustion engine.

[0111] The mode information acquisition unit 110 transmits information about the selected control mode and information about the target virtual vehicle to the engine pseudo sound generation unit 160 .

[0112] The engine pseudo sound generation unit 160 functions when the control mode is the on-demand mode and the target virtual vehicle is a virtual vehicle equipped with an internal combustion engine. At this time, the sound control device 101b reads out a vehicle model 200 (target vehicle model) of the target virtual vehicle from the vehicle model database D10 based on information about the target virtual vehicle from the mode information acquisition unit 110. Parameters 201 are also set according to the target virtual vehicle. The engine pseudo sound generation unit 160 then generates an engine pseudo sound based on the virtual engine torque and virtual engine speed calculated using the target vehicle model.

[0113] The engine false sound generation unit 160 acquires the sound source of the engine false sound for the target virtual vehicle by referring to the storage device 103. The storage device 103 may store the sound source of the engine false sound for each virtual vehicle equipped with an internal combustion engine.

[0114] The pseudoengine sound generation unit 160 includes a process 161 for calculating engine sound pressure and a process 162 for calculating engine sound frequency. In process 161, the sound pressure of the pseudoengine sound is calculated from the virtual engine torque using a sound pressure map M11. The sound pressure map M11 is created so that the sound pressure increases as the virtual engine torque increases. In process 162, the frequency of the virtual engine sound is calculated from the virtual engine rotation speed using a frequency map M12. The frequency map M12 is created so that the frequency increases as the virtual engine rotation speed increases. The virtual engine torque and the virtual engine rotation speed change depending on the operation of the driving operation members by the driver.

[0115] The sound control device 101b outputs the pseudo engine sound generated by the pseudo engine sound generation unit 160 from the in-vehicle speaker 21. By performing sound control related to the pseudo engine sound by the sound control device 101b in this way, when the control mode is the on-demand mode, the driver can be given an even more realistic feeling as if he or she is driving the target virtual vehicle.

[0116] 6 Display Control Device The control device 101 according to this embodiment may function as a display control device that controls the HMI 20 to display the virtual engine speed and virtual gear position of the target virtual vehicle when the control mode is the on-demand mode, thereby providing the driver with an even more realistic feeling that they are driving the target virtual vehicle.

[0117] 7. Other The electric vehicle 100 according to the above embodiment is a front-wheel drive vehicle in which one electric motor 2 drives the front wheels. However, the technical features according to this embodiment can also be applied to electric vehicles in which two electric motors are arranged at the front and rear to drive the front and rear wheels, respectively. They can also be applied to electric vehicles in which each wheel is equipped with an in-wheel motor.

[0118] The technical features of this embodiment are not limited to battery electric vehicles, but can be widely applied to any electric vehicle that uses an electric motor as a driving power unit. For example, the technical features of this embodiment can be applied to hybrid electric vehicles (HEVs) and plug-in hybrid electric vehicles (PHEVs) that have a mode in which they run solely on the driving force of the electric motor. They can also be applied to fuel cell electric vehicles (FCEVs) that supply electric energy generated by a fuel cell to the electric motor. [Explanation of symbols]

[0119] 2 electric motor, 14 battery, 22 accelerator pedal, 24 brake pedal, 50 sensor system, 100 electric vehicle, 101 control device, 102 processing circuit, 103 storage devices, 104 computer programs, 105 data, 200 vehicle models, 201 parameters

Claims

1. An electric vehicle having an electric motor as a drive source, Accelerator pedal and a processing circuit; a storage device that stores a database that manages a plurality of vehicle models that are modeled based on a plurality of virtual vehicles that have different acceleration characteristics in response to a driver's driving operation; Equipped with The processing circuitry a target vehicle model corresponding to a target virtual vehicle selected by the driver from among the plurality of virtual vehicles is read from the database; calculating a virtual acceleration of the target virtual vehicle in response to an operation of the accelerator pedal using the target vehicle model based on the operation state of the accelerator pedal and a running state of the electric vehicle; determining whether the virtual acceleration exceeds a achievable acceleration of the electric vehicle during an acceleration period of the electric vehicle when the accelerator pedal is depressed; When it is determined that the virtual acceleration during the acceleration period exceeds the achievable acceleration of the electric vehicle, a correction process is executed to correct the virtual acceleration so as to change the time change of the virtual acceleration during the acceleration period in accordance with the excess amount; The electric motor is controlled so that the acceleration of the electric vehicle is the corrected virtual acceleration. It is configured as follows: Electric car.

2. 10. The electric vehicle according to claim 1, In the correction process, the processing circuit The virtual acceleration is corrected so that the jerk when the virtual acceleration increases during the acceleration period is greater than that before the correction. It is configured as follows: Electric car.

3. 10. The electric vehicle according to claim 1, In the correction process, the processing circuit The virtual acceleration is corrected so that the virtual acceleration temporarily decreases before increasing during the acceleration period. It is configured as follows: Electric car.

4. 10. The electric vehicle according to claim 1, In the correction process, the processing circuit The virtual acceleration is corrected so that the time it takes for the virtual acceleration to increase during the acceleration period is shorter than before the correction. It is configured as follows: Electric car.

5. 5. The electric vehicle according to claim 1, The processing circuitry calculating a target driving force of the electric vehicle for setting the acceleration of the electric vehicle to the virtual acceleration; The motor torque output by the electric motor is changed so as to impart the target driving force to the electric vehicle. It is configured as follows: Electric car.

6. A control device for an electric vehicle having an electric motor as a drive source, a processing circuit; a storage device that stores a database that manages a plurality of vehicle models that are modeled based on a plurality of virtual vehicles that have different acceleration characteristics in response to a driver's driving operation; Equipped with the electric vehicle includes an accelerator pedal; The processing circuitry a target vehicle model corresponding to a target virtual vehicle selected by the driver from among the plurality of virtual vehicles is read from the database; calculating a virtual acceleration of the target virtual vehicle in response to an operation of the accelerator pedal using the target vehicle model based on the operation state of the accelerator pedal and a running state of the electric vehicle; determining whether the virtual acceleration exceeds a realizable acceleration of the electric vehicle during an acceleration period of the electric vehicle when the accelerator pedal is depressed; When it is determined that the virtual acceleration during the acceleration period exceeds the achievable acceleration of the electric vehicle, a correction process is executed to correct the virtual acceleration so as to change the time change of the virtual acceleration during the acceleration period in accordance with the excess amount; The electric motor is controlled so that the acceleration of the electric vehicle is the corrected virtual acceleration. It is configured as follows: Control device.

7. The control device according to claim 6, In the correction process, the processing circuit The virtual acceleration is corrected so that the jerk when the virtual acceleration increases during the acceleration period is greater than that before the correction. It is configured as follows: Control device.

8. The control device according to claim 6, In the correction process, the processing circuit The virtual acceleration is corrected so that the virtual acceleration temporarily decreases before increasing during the acceleration period. It is configured as follows: Control device.

9. The control device according to claim 6, In the correction process, the processing circuit The virtual acceleration is corrected so that the time it takes for the virtual acceleration to increase during the acceleration period is shorter than before the correction. It is configured as follows: Control device.

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