Vehicle control method, vehicle control device, and electric automobile

Abstract

To provide a vehicle control method for correctly informing a driver of a content of switching of a plurality of driving modes, of an electric automobile including a control mode of performing output control of an electric motor on the basis of manual shift operation by the driver.SOLUTION: When acquiring setting information of a driving mode possessed by an electric automobile and detecting mode switching of the driving mode on the basis of the setting information, a vehicle control method outputs a notification sound for notifying a driver of mode switching from a speaker. The driving mode includes a custom mode of performing at least one of output control of an electric motor based on operation information of a manual driving element of the electric automobile, and output control of a pseudo engine sound generated on the basis of the operation information. An output form of the notification sound output from the speaker when the switching to the custom mode is detected is different from an output form of the notification sound output from the speaker when the switching from the custom mode is detected.SELECTED DRAWING: Figure 11

Description

[Technical field]

[0001] The present disclosure relates to a technique applied to an electric vehicle that uses an electric motor as a power device for running. [Background technology]

[0002] Japanese Patent No. 6787507 discloses an electric vehicle that uses an electric motor as a power unit for traveling. This conventional electric vehicle controls the output of the electric motor so as to simulate the torque characteristics specific to an internal combustion engine vehicle with a manual transmission (hereinafter also referred to as an "MT engine vehicle"). The output of the electric motor is controlled based on a signal from a pseudo manual transmission operated by the driver. The pseudo manual transmission has a configuration similar to that of a manual transmission installed in a MT engine vehicle. [Prior art documents] [Patent documents]

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

[0004] According to the conventional electric vehicle described above, in addition to a control mode in which the output of the electric motor is controlled based on the manual shifting operation by the driver, a control mode in which the output of the electric motor is normally controlled without being based on the manual shifting operation can be set as two driving modes of the electric vehicle. By switching between these driving modes based on the mode designation operation by the driver, the driver can get the feeling of driving a MT engine vehicle at the time and place of his / her choice.

[0005] However, as the number of driving modes that can be set in an electric vehicle increases, there is a possibility that the driver himself may misunderstand the driving mode that he or she has specified. In that case, for example, even if a driving mode in which the output control of the electric motor is performed without a manual shifting operation is specified, the driver may misunderstand the content of the driving mode and perform a manual shifting operation, which may cause the driver to feel uncomfortable with the behavior of the electric vehicle. This problem is expected to occur when switching between driving modes. Therefore, an improvement is desired to correctly inform the driver of the content of the switching of the driving mode.

[0006] The present disclosure has been made in consideration of the above problems. One objective of the present disclosure is to provide a technology that can correctly inform a driver of the switching between a plurality of driving modes of an electric vehicle, including a control mode in which the output of an electric motor is controlled based on a manual gear shift operation by the driver. [Means for solving the problem]

[0007] A first aspect of the present disclosure is a vehicle control method applied to an electric vehicle that uses an electric motor as a power unit for traveling, and has the following features. The vehicle control method includes a step of acquiring setting information of a driving mode of the electric vehicle, and a step of outputting a notification sound from a speaker of the electric vehicle to notify a driver of the electric vehicle of the mode switch when a mode switch of the driving mode is detected based on the setting information. The driving modes include a custom mode in which at least one of output control of the electric motor based on operation information of a manual driving element of the electric vehicle and output control of a pseudo engine sound generated based on the operation information is performed. The output form of the notification sound output from the speaker when a switch to the custom mode is detected is different from that of the notification sound output from the speaker when a switch from the custom mode is detected.

[0008] A second aspect of the present disclosure is a vehicle control device that is applied to an electric vehicle that uses an electric motor as a power unit for traveling, and has the following features. The vehicle control device includes a processor that performs various processes, and when a mode change of the driving mode is detected based on the setting information, the processor outputs a notification sound to a speaker of the electric vehicle to notify a driver of the electric vehicle of the mode change. The driving modes include a custom mode in which at least one of output control of the electric motor based on operation information of a manual driving element of the electric vehicle and output control of a pseudo engine sound generated based on the operation information is performed. The output form of the notification sound output from the speaker when a switch to the custom mode is detected is different from that of the notification sound output from the speaker when a switch from the custom mode is detected.

[0009] A third aspect of the present disclosure is an electric vehicle that uses an electric motor as a power unit for traveling, and has the following characteristics. The electric vehicle includes a speaker, a manual driving element, and a processor that performs various processes. The processor acquires setting information of a driving mode of the electric vehicle, and when a mode switch of the driving mode is detected based on the setting information, outputs a notification sound to the speaker of the electric vehicle to notify the driver of the electric vehicle of the mode switch. The driving modes include a custom mode in which at least one of output control of the electric motor based on operation information of a manual driving element of the electric vehicle and output control of a pseudo engine sound generated based on the operation information is performed. The output form of the notification sound output from the speaker when a switch to the custom mode is detected is different from that of the notification sound output from the speaker when a switch from the custom mode is detected. Effect of the Invention

[0010] According to the present disclosure, it is possible to change the output state of the notification sound from the speaker when switching from a driving mode other than the custom mode to the custom mode is detected, and the output state of the notification sound when switching from the custom mode to the other driving mode is detected. Therefore, it is possible to correctly inform the driver that the custom mode has started and ended. This leads to a sense of security when using the custom mode, and it is possible to provide the driver with the sensation obtained by driving an engine vehicle in various driving situations. [Brief description of the drawings]

[0011] [Figure 1] 1 is a conceptual diagram showing an electric vehicle and a vehicle control device according to an embodiment; [Diagram 2] FIG. 1 is a block diagram showing a first configuration example of a power control system for an electric vehicle. [Diagram 3] 4A to 4C are diagrams illustrating examples of an engine model, a clutch model, and a transmission model that configure an MT engine vehicle model. [Figure 4] FIG. 13 is a diagram showing a comparison of the torque characteristics of an electric motor achieved by motor control using a MT engine vehicle model with the torque characteristics of an electric motor achieved by normal motor control in an electric vehicle. [Diagram 5] FIG. 4 is a block diagram showing a second configuration example of a power control system for an electric vehicle. [Figure 6] 2 is a block diagram showing an example of a functional configuration of a vehicle control device related to output control of a pseudo engine sound. FIG. [Figure 7] 13 is a block diagram showing another example of a functional configuration of a vehicle control device related to output control of a pseudo engine sound. FIG. [Figure 8] FIG. 2 is a diagram illustrating an operation mode assumed in the embodiment. [Figure 9] 2 is a block diagram showing an example of a functional configuration of a vehicle control device related to output control of a notification sound. [Figure 10]13 is a block diagram showing another example of a functional configuration of a vehicle control device related to output control of a notification sound. [Figure 11] 1 is a flowchart showing a computer processing flow particularly related to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] The embodiments of the present disclosure will be described with reference to the accompanying drawings. In each drawing, the same or corresponding components are denoted by the same reference numerals, and the description thereof will be simplified or omitted.

[0013] 1. Overall structure 1 is a conceptual diagram showing an electric vehicle 10 according to an embodiment of the present disclosure and a vehicle control device 100 applied to the electric vehicle 10. The electric vehicle 10 is equipped with an electric motor 44. Examples of the electric motor 44 include a brushless DC motor and a three-phase AC synchronous motor. The electric vehicle 10 uses the electric motor 44 as a power unit for traveling.

[0014] The electric vehicle 10 is also equipped with various sensors 12. The various sensors 12 include operation state sensors such as an accelerator position sensor, a brake position sensor, and a shift position sensor, and driving state sensors such as a wheel speed sensor, an acceleration sensor, and a rotational speed sensor. The accelerator position sensor detects the amount of operation of the accelerator pedal (accelerator opening). The brake position sensor detects the amount of operation of the brake pedal. The shift position sensor detects the shift position. The wheel speed sensor detects the rotational speed of the wheels of the electric vehicle 10. The acceleration sensor detects the lateral acceleration and longitudinal acceleration of the electric vehicle 10. The rotational speed sensor detects the rotational speed of the electric motor 44.

[0015] The various sensors 12 also include position sensors such as a Global Navigation Satellite System (GNSS) sensor, and recognition sensors such as a camera, a radar, and a Laser Imaging Detection and Ranging (LIDAR). The GNSS detects the position and attitude of the electric vehicle 10. The camera captures an image of at least the area in front of the electric vehicle 10. The radar and LIDAR recognize the situation around the electric vehicle 10.

[0016] The electric vehicle 10 also includes various switches 14. The various switches 14 include operational switches such as a turn signal switch, a light switch, and an ignition switch. The turn signal switch switches the operating state (ON / OFF) of a direction indicator light. The light switch switches the operating state (ON / OFF) of a light (e.g., a headlight). The ignition switch switches the operating state (ON / OFF) of a power supply circuit of the electric vehicle 10. The various switches 14 also include a mode change switch that changes the driving mode of the electric vehicle 10.

[0017] The electric vehicle 10 further includes speakers 16. The speakers 16 output sound into the cabin of the electric vehicle 10. The speakers 16 include, for example, front speakers provided at the front of the cabin and rear speakers provided at the rear of the cabin. The total number of speakers constituting the speaker 16 and the layout of the speakers 16 can be changed as desired.

[0018] The vehicle control device 100 controls the output of the electric motor 44 to run the electric vehicle 10. The output control of the electric motor 44 by the vehicle control device 100 includes normal control for operating the electric vehicle 10 as a general electric vehicle, and control for operating the electric vehicle 10 so as to simulate the torque characteristics of a manual transmission engine vehicle. The latter will be described later.

[0019] The vehicle control device 100 also generates a sound (hereinafter also referred to as "indoor sound") to be output from the speaker 16. The vehicle control device 100 also outputs the generated indoor sound from the speaker 16. For example, the vehicle control device 100 generates a pseudo engine sound as the indoor sound, and outputs the generated indoor sound from the speaker 16. In another example, the vehicle control device 100 generates indoor sound including the pseudo engine sound, and outputs the generated indoor sound from the speaker 16. The output control of the pseudo engine sound will be described later.

[0020] The entire vehicle control device 100 may be mounted on the electric vehicle 10. As another example, at least a part of the vehicle control device 100 may be included in a management server external to the electric vehicle 10. In that case, the vehicle control device 100 may generate an interior sound remotely, receive the generated interior sound, and output it from the speaker 16.

[0021] Generally speaking, the vehicle control device 100 includes at least one processor 102 and at least one storage device 104. The processor 102 executes various processes. Examples of the processor 102 include a central processing unit (CPU), a graphics processing unit (GPU), an application specific integrated circuit (ASIC), and a field-programmable gate array (FPGA). The storage device 104 stores (stores) various information. Examples of the storage device 104 include a volatile memory, a non-volatile memory, a hard disk drive (HDD), and a solid state drive (SSD).

[0022] 2. Electric motor power control The electric motor used as the power unit for driving a general electric vehicle has a significantly different torque characteristic from the internal combustion engine used as the power unit for driving a conventional engine vehicle. Due to the difference in torque characteristics of the power unit, a transmission is essential for a conventional engine vehicle, whereas an electric vehicle generally does not have a transmission. In addition, a general electric vehicle does not have a manual transmission operated by the driver. For this reason, the driving sensation is significantly different between driving an MT engine vehicle and driving an electric vehicle.

[0023] On the other hand, the torque of an electric motor can be controlled relatively easily by controlling the applied voltage and the magnetic field. Therefore, with an electric motor, it is possible to obtain a desired torque characteristic within the operating range of the electric motor by implementing appropriate control. By utilizing this feature, the torque of an electric vehicle can be controlled to simulate the torque characteristic unique to a manual transmission vehicle. In addition, an electric vehicle can be provided with a pseudo manual transmission so that the driver can obtain the same driving sensation as a manual transmission vehicle. This makes it possible to simulate a manual transmission vehicle in an electric vehicle.

[0024] In the embodiment, the output of the electric motor 44 is controlled so as to simulate torque characteristics specific to MT engine vehicles. By controlling the output of the electric motor 44, the driver of the electric vehicle 10 can feel as if he or she is driving a MT engine vehicle. The control mode of the electric motor 44 for simulating the torque characteristics specific to MT engine vehicles in this way is also referred to as the "manual mode" below. Moreover, the control mode of the electric motor 44 for driving the electric vehicle 10 as a general electric vehicle is also referred to as the "automatic mode" below.

[0025] An example of the configuration of the electric vehicle 10 having a manual mode will be described below.

[0026] 2-1. First configuration example 2 is a block diagram showing a first example of the configuration of a power control system of the electric vehicle 10. The electric vehicle 10 includes an electric motor 44, a battery 46, and an inverter 42. The electric motor 44 is a power device for driving the electric vehicle 10. The battery 46 stores electric energy for driving the electric motor 44. In other words, the electric vehicle 10 is a battery electric vehicle (BEV) that runs on electric energy stored in the battery 46. The inverter 42 converts DC power input from the battery 46 during acceleration into drive power for the electric motor 44. The inverter 42 also converts regenerative power input from the electric motor 44 during deceleration into DC power and charges the battery 46.

[0027] The electric vehicle 10 is provided with an accelerator pedal 22 that allows the driver to input an acceleration request to the electric vehicle 10. The accelerator pedal 22 is provided with an accelerator position sensor 32 that detects the accelerator opening degree.

[0028] The electric vehicle 10 is equipped with a pseudo shift paddle 24. This pseudo shift paddle 24 is a dummy that is different from an original paddle-type shifter. The pseudo shift paddle 24 has a structure similar to a shift paddle equipped in a clutch pedal-less MT engine vehicle. The pseudo shift paddle 24 is attached to the steering wheel. The pseudo shift paddle 24 is equipped with an upshift switch 34u and a downshift switch 34d that determine the operation position. The upshift switch 34u issues an upshift signal when pulled toward the driver, and the downshift switch 34d issues a downshift signal when pulled toward the driver.

[0029] Wheel speed sensors 36 are provided on the wheels 26 of the electric vehicle 10. The wheel speed sensors 36 are used as vehicle speed sensors for detecting the speed of the electric vehicle 10. In addition, the electric motor 44 is provided with a rotation speed sensor 38 for detecting the rotation speed thereof.

[0030] The electric vehicle 10 includes a control device 50. The control device 50 is typically an electronic control unit (ECU) mounted on the electric vehicle 10. The control device 50 may be a combination of multiple ECUs. The control device 50 includes an interface, a memory, and a processor. An in-vehicle network is connected to the interface. The memory includes a RAM for temporarily recording data, and a ROM for storing programs executable by the processor and various data related to the programs. The programs are made up of multiple instructions. The processor reads the programs and data from the memory and executes them, and generates control signals based on signals acquired from each sensor.

[0031] For example, the control device 50 controls the electric motor 44 by PWM control of the inverter 42. Signals from the accelerator position sensor 32, the pseudo shift paddle 24, the wheel speed sensor 36, the rotation speed sensor 38, the upshift switch 34u, and the downshift switch 34d are input to the control device 50. The control device 50 processes these signals and calculates a motor torque command value for PWM controlling the inverter 42.

[0032] The control device 50 includes an automatic mode and a manual mode as control modes. The automatic mode is a normal control mode for driving the electric vehicle 10 as a general electric vehicle. The automatic mode is programmed to continuously change the output of the electric motor 44 in response to the operation of the accelerator pedal 22. On the other hand, the manual mode is a control mode for driving the electric vehicle 10 like a manual transmission engine vehicle. The manual mode is programmed to change the output characteristic of the electric motor 44 in response to the operation of the accelerator pedal 22 in response to the operation of the pseudo shift paddle 24. In other words, the manual mode is a control mode in which the output of the electric motor 44 can be changed in response to the driving operation of a manual driving element other than the accelerator pedal 22 or the brake pedal.

[0033] The control device 50 includes an automatic mode torque calculation unit 54 and a manual mode torque calculation unit 56. Each of the units 54 and 56 may be an independent ECU, or may be an ECU function obtained by executing a program recorded in a memory by a processor.

[0034] The automatic mode torque calculation unit 54 has a function of calculating the motor torque when the electric motor 44 is controlled in the automatic mode. A motor torque command map is stored in the automatic mode torque calculation unit 54. The motor torque command map is a map that determines the motor torque from the accelerator opening and the rotation speed of the electric motor 44. The signal of the accelerator position sensor 32 and the signal of the rotation speed sensor 38 are input to each parameter of the motor torque command map. The motor torque command map outputs a motor torque corresponding to these signals. Therefore, in the automatic mode, even if the driver operates the pseudo shift paddle 24, the operation is not reflected in the motor torque.

[0035] The manual mode torque calculation unit 56 includes a manual transmission vehicle model. The manual transmission vehicle model is a model for calculating the drive wheel torque that should be obtained by operating the accelerator pedal 22 and the pseudo shift paddles 24 when the electric vehicle 10 is assumed to be a manual transmission vehicle.

[0036] The MT engine vehicle model provided in the manual mode torque calculation unit 56 will be described with reference to Fig. 3. As shown in Fig. 3, the MT engine vehicle model includes an engine model 561, a clutch model 562, and a transmission model 563. The engine, clutch, and transmission virtually realized by the MT engine vehicle model are referred to as a virtual engine, a virtual clutch, and a virtual transmission, respectively. The engine model 561 models a virtual engine. The clutch model 562 models a virtual clutch. The transmission model 563 models a virtual transmission.

[0037] The engine model 561 calculates a virtual engine rotation speed Ne and a virtual engine output torque Teout. The virtual engine rotation speed Ne is calculated based on the rotation speed Nw of the wheels, the total reduction ratio R, and the slip ratio Rslip of the virtual clutch. For example, the virtual engine rotation speed Ne is expressed by the following equation (1). Formula (1): Ne = Nw × R / (1 - Rslip)

[0038] The virtual engine output torque Teout is calculated from the virtual engine rotation speed Ne and the accelerator opening Pap. To calculate the virtual engine output torque Teout, a map is used that defines the relationship between the accelerator opening Pap, the virtual engine rotation speed Ne, and the virtual engine output torque Teout, as shown in FIG. 3. In this map, the virtual engine output torque Teout for the virtual engine rotation speed Ne is given for each accelerator opening Pap. The torque characteristics shown in FIG. 3 can be set to characteristics assuming a gasoline engine or to characteristics assuming a diesel engine. In addition, the torque characteristics can be set to characteristics assuming a naturally aspirated engine or to characteristics assuming a supercharged engine.

[0039] The clutch model 562 calculates a torque transmission gain k. The torque transmission gain k is a gain for calculating the degree of torque transmission of the virtual clutch according to the virtual clutch opening Pc. The virtual clutch opening Pc is usually 0%, and is temporarily opened to 100% in conjunction with the switching of the virtual gear stage of the virtual transmission. The clutch model 562 has a map as shown in FIG. 3. In this map, the torque transmission gain k is given for the virtual clutch opening Pc. In FIG. 3, Pc0 corresponds to the position where the virtual clutch opening Pc is 0%, and Pc3 corresponds to the position where the virtual clutch opening Pc is 100%. The ranges from Pc0 to Pc1 and from Pc2 to Pc3 are dead zones in which the torque transmission gain k does not change depending on the virtual clutch opening Pc. The clutch model 562 calculates the clutch output torque Tcout using the torque transmission gain k. The clutch output torque Tcout is the torque output from the virtual clutch. For example, the clutch output torque Tcout is given by the product of the virtual engine output torque Teout and the torque transmission gain k (Tcout=Teout×k).

[0040] Further, the clutch model 562 calculates a slip ratio Rslip. The slip ratio Rslip is used to calculate a virtual engine rotation speed Ne in the engine model 561. To calculate the slip ratio Rslip, a map in which the slip ratio Rslip is given with respect to the virtual clutch opening degree Pc can be used, similar to the torque transmission gain k.

[0041] The transmission model 563 calculates a gear ratio (speed ratio) r. The gear ratio r is a gear ratio determined by the virtual gear stage GP in the virtual transmission. In response to an upshift operation of the pseudo shift paddle 24, the virtual gear stage GP is increased by one stage. On the other hand, in response to a downshift operation of the pseudo shift paddle 24, the virtual gear stage GP is decreased by one stage. The transmission model 563 has a map as shown in FIG. 3. In this map, the gear ratio r is given to the virtual gear stage GP so that the gear ratio r becomes smaller as the virtual gear stage GP increases. The transmission model 563 calculates the transmission output torque Tgout using the gear ratio r and the clutch output torque Tcout obtained from the map. For example, the transmission output torque Tgout is given as the product of the clutch output torque Tcout and the gear ratio r (Tgout=Tcout×r). The transmission output torque Tgout changes discontinuously in response to the switching of the gear ratio r. This discontinuous change in the transmission output torque Tgout generates a gear shift shock, creating the feeling that the vehicle is equipped with a stepped transmission.

[0042] The MT engine vehicle model calculates the driving wheel torque Tw using a predetermined reduction gear ratio rr. The reduction gear ratio rr is a fixed value determined by the mechanical structure from the virtual transmission to the driving wheels. The value obtained by multiplying the reduction gear ratio rr by the gear ratio r is the above-mentioned overall reduction gear ratio R. The MT engine vehicle model calculates the driving wheel torque Tw from the transmission output torque Tgout and the reduction gear ratio rr. For example, the driving wheel torque Tw is given by the product of the transmission output torque Tgout and the reduction gear ratio rr (Tw=Tgout×rr).

[0043] The control device 50 converts the driving wheel torque Tw calculated by the MT engine vehicle model into a required motor torque Tm. The required motor torque Tm is the motor torque required to realize the driving wheel torque Tw calculated by the MT engine vehicle model. The reduction ratio from the output shaft of the electric motor 44 to the driving wheels is used to convert the driving wheel torque Tw into the required motor torque Tm. Then, the control device 50 controls the inverter 42 according to the required motor torque Tm to control the electric motor 44.

[0044] Fig. 4 is a diagram showing torque characteristics of the electric motor 44 realized by motor control using the MT engine vehicle model, compared with torque characteristics of the electric motor 44 realized by normal motor control for an electric vehicle (EV). According to motor control using the MT engine vehicle model, as shown in Fig. 4, it is possible to realize torque characteristics (solid line in the figure) that mimic the torque characteristics of a MT engine vehicle according to the virtual gear stage set by the pseudo shift paddle 24. In Fig. 4, the number of gear stages is six.

[0045] 2-2. Second configuration example 5 is a block diagram showing a second configuration example of the power control system of the electric vehicle 10. Here, only the configuration different from the first configuration example described above will be explained. Specifically, in the second configuration example, the electric vehicle 10 is provided with a pseudo shift lever 27 and a pseudo clutch pedal 28 instead of the pseudo shift paddle 24 provided in the first configuration example. The pseudo shift lever 27 and the pseudo clutch pedal 28 are merely dummies that are different from an actual shift lever and clutch pedal.

[0046] The pseudo shift lever 27 has a structure simulating a shift lever equipped in a MT engine vehicle. The arrangement and operation feel of the pseudo shift lever 27 are the same as those of an actual MT engine vehicle. The pseudo shift lever 27 has positions corresponding to each gear stage, for example, 1st gear, 2nd gear, 3rd gear, 4th gear, 5th gear, 6th gear, reverse, and neutral. The pseudo shift lever 27 is provided with a shift position sensor 27a that detects the gear stage by determining which position the pseudo shift lever 27 is in.

[0047] The pseudo clutch pedal 28 has a structure simulating a clutch pedal equipped in a MT engine vehicle. The arrangement and operation feel of the pseudo clutch pedal 28 are the same as those of an actual MT engine vehicle. The pseudo clutch pedal 28 is operated when the pseudo shift lever 27 is operated. That is, the driver depresses the pseudo clutch pedal 28 when he / she wishes to change the gear setting with the pseudo shift lever 27, and stops depressing the pseudo clutch pedal 28 when the gear setting change is completed and returns the pseudo clutch pedal 28 to its original position. The pseudo clutch pedal 28 is provided with a clutch position sensor 28a for detecting the amount of depression of the pseudo clutch pedal 28.

[0048] Signals are input to the control device 50 from the accelerator position sensor 32, the shift position sensor 27a, the clutch position sensor 28a, the wheel speed sensor 36, and the rotation speed sensor 38. The control device 50 processes these signals and calculates a motor torque command value for PWM controlling the inverter 42.

[0049] The control device 50 includes an automatic mode and a manual mode as control modes, similarly to the first configuration example described above. The automatic mode is programmed to continuously change the output of the electric motor 44 in response to the operation of the accelerator pedal 22. On the other hand, the manual mode is a control mode for driving the electric vehicle 10 as if it were a MT engine vehicle. The manual mode is programmed to change the output of the electric motor 44 in response to the operation of the accelerator pedal 22 in response to the operation of the pseudo clutch pedal 28 and the pseudo shift lever 27.

[0050] The vehicle model provided in the manual mode torque calculation unit 56 is similar to that shown in Fig. 3. However, the virtual clutch opening degree Pc is replaced with the depression amount of the pseudo clutch pedal 28 detected by the clutch position sensor 28a. Also, the virtual gear stage GP is determined by the position of the pseudo shift lever 27 detected by the shift position sensor 27a.

[0051] 3. Output control of simulated engine sound In the embodiment, output control of the pseudo engine sound is performed instead of or together with output control of the electric motor. Fig. 6 is a block diagram showing an example of a functional configuration of the vehicle control device 100 related to output control of the pseudo engine sound. The vehicle control device 100 includes an information acquisition unit 110, a vehicle sound source management unit 120, an engine sound generation unit 130, and a sound output control unit 140 as functional blocks related to the pseudo engine sound. These functional blocks are realized by, for example, cooperation between the processor 102 and the storage device 104.

[0052] The information acquisition unit 110 acquires information BEV about the electric vehicle 10. The information BEV includes information about the running state of the electric vehicle 10, information about the running environment of the electric vehicle 10, etc. The information BEV is typically detected by various sensors 12. Part of the information about the running environment of the electric vehicle 10 may be acquired by combining information detected by the various sensors 12 (e.g., position information of the electric vehicle 10) with map data.

[0053] The information BEV also includes a virtual engine rotation speed Ne. Here, it is assumed that the electric vehicle 10 uses a virtual engine as a power unit for traveling. The virtual engine rotation speed Ne is the rotation speed of the virtual engine when it is assumed that the electric vehicle 10 is driven by the virtual engine. For example, the information acquisition unit 110 may calculate the virtual engine rotation speed Ne so that it increases as the wheel speed increases. Furthermore, when the electric vehicle 10 has a manual mode, the information acquisition unit 110 may calculate the virtual engine rotation speed Ne in the manual mode based on the wheel speed, the overall reduction ratio, and the slip ratio of the virtual clutch. The calculation of the virtual engine rotation speed Ne in the manual mode can be performed, for example, using the above formula (1).

[0054] The vehicle sound source management unit 120 stores sound source data EVS of the engine vehicle used to generate the pseudo engine sound. The vehicle sound source management unit 120 is mainly realized by the storage device 104. Typically, the sound source data EVS includes a plurality of types of sound source data. The plurality of types of sound source data includes, for example, sound source data (for low rotation speed, medium rotation speed, and high rotation speed) of sound caused by engine combustion, sound source data (for low rotation speed, medium rotation speed, and high rotation speed) of sound caused by operation of the drive system such as gears, sound source data of noise sound, sound source data of event sound (for example, stall sound), and the like. Each sound source data is generated in advance through a simulation based on an engine model and a vehicle model of the engine vehicle. Each sound source data is flexibly adjustable. That is, at least one of the sound pressure and frequency of the sound indicated by the sound source data is flexibly adjustable.

[0055] The engine sound generation unit 130 (engine sound simulator) is a simulator that generates a pseudo engine sound. The engine sound generation unit 130 acquires at least a part of the information BEV from the information acquisition unit 110. In particular, the engine sound generation unit 130 acquires information on the virtual engine rotation speed Ne and the vehicle speed from the information acquisition unit 110. The engine sound generation unit 130 also reads the sound source data EVS of the engine vehicle from the vehicle sound source management unit 120. Then, the engine sound generation unit 130 generates a pseudo engine sound according to the driving state of the electric vehicle 10 (the virtual engine rotation speed Ne and the vehicle speed) by combining one or more sound source data included in the sound source data EVS of the engine vehicle. The engine sound data EGS is data indicating the generated pseudo engine sound.

[0056] Note that generating a pseudo engine sound is a well-known technique, and there is no particular limitation on the method of generating the pseudo engine sound that can be applied to the present disclosure. For example, the pseudo engine sound may be generated by a well-known engine sound simulator used in games, etc. A method may be used in which a map of virtual engine speed Ne vs. frequency and a map of virtual engine torque vs. sound pressure are prepared, and the frequency of the pseudo engine sound is increased or decreased in proportion to the virtual engine speed Ne, and the sound pressure of the pseudo engine sound is increased or decreased in proportion to the virtual engine torque.

[0057] The sound output control unit 140 receives the engine sound data EGS generated by the engine sound generation unit 130. Then, the sound output control unit 140 outputs the engine sound data EGS to the speaker 16. When outputting the engine sound data EGS, the sound output control unit 140 controls the sound pressure of the pseudo engine sound by controlling an amplifier. In addition, the sound output control unit 140 changes the frequency of the pseudo engine sound by controlling an FMC (frequency modulator).

[0058] FIG. 7 is a block diagram showing another example of the functional configuration of the vehicle control device 100 related to the output control of the pseudo engine sound. In the example shown in FIG. 7, the vehicle sound source management unit 120 stores sound source data EVS (EVS1, . . . EVSn) of multiple types of engine vehicles corresponding to multiple vehicle models (1, . . . , n). That is, the vehicle sound source management unit 120 stores sound source data EVS of the engine vehicle for each vehicle model. The sound source data EVSk (1 ≦ k ≦ n) is generated in advance based on the engine model or vehicle model of the corresponding vehicle model. The driver may specify a vehicle model of his / her preference from among multiple vehicle models. In that case, the engine sound generation unit 130 acquires sound source data EVSk corresponding to the vehicle model specified by the driver. Then, the engine sound generation unit 130 generates a pseudo engine sound using the acquired sound source data EVSk of the engine vehicle. This allows the driver to get the feeling that he / she is driving a vehicle model of his / her preference.

[0059] 4. Driving mode switching notification 4-1. Necessity of switching notification As described above, in the embodiment, at least one of the electric motor output control and the pseudo engine sound output control is performed. Therefore, the automatic mode and the manual mode described in the explanation of the electric motor output control are subdivided in consideration of the execution of the pseudo engine sound output control. FIG. 8 is a diagram explaining the driving modes assumed in the embodiment. In the example shown in FIG. 8, the automatic mode has a normal EV mode MD0 and a custom EV mode MD2. The manual mode has custom EV modes MD1 and MD3.

[0060] Normal EV mode MD0 and custom EV mode MD1 are driving modes in which only the output control of the electric motor is performed. In normal EV mode MD0, normal control is performed to drive the electric vehicle 10 as a general electric vehicle. In custom EV mode MD1, control is performed to drive the electric vehicle 10 so as to simulate the torque characteristics of a manual transmission engine vehicle. Custom EV mode MD1 is an example of a "custom mode" in the present disclosure, and is also referred to as an MT mode.

[0061] The custom EV modes MD2 and MD4 are driving modes in which output control of the pseudo engine sound is performed. In the custom EV modes MD2 and MD4, the output control of the electric motor is also performed. However, the output control of the electric motor in the custom EV mode MD2 is the same as that in the normal EV mode MD0. Moreover, the output control of the electric motor in the custom EV mode MD4 is the same as that in the custom EV mode MD2. The custom EV modes MD2 and MD4 are also examples of the "custom mode" of the present disclosure. The custom EV mode MD2 is also referred to as a sound mode, and the custom EV mode MD4 is also referred to as an MT sound mode.

[0062] The driving mode switching shown in FIG. 8 occurs between any two types of driving modes. The driving mode switching is performed based on the driver's expression of intention to switch. For example, the driver expresses his / her intention by operating a mode switching switch. In another example, the driver expresses his / her intention by a predetermined gesture. In this case, the expression of intention is confirmed, for example, by recognizing the predetermined gesture through analysis of a camera image. In yet another example, the driver expresses his / her intention by uttering a predetermined sound. In this case, the expression of intention is confirmed, for example, by recognizing the predetermined sound through analysis of a microphone sound.

[0063] In this manner, in the embodiment, a normal EV mode and three types of custom EV modes are assumed. Therefore, the driver himself may misunderstand the driving mode that is switched based on the driver's intention. In that case, for example, when switching from the automatic mode (mode MD0) to the manual mode (mode MD1) or from the automatic mode (mode MD2) to the manual mode (mode MD4), the driver may feel uncomfortable with the behavior of the electric vehicle.

[0064] Therefore, in the embodiment, when a change in the driving mode is detected, a notification sound corresponding to the driving mode before or after the change is output from the speaker 16. The driving mode before or after the change is based on the custom EV mode (mode MD1, MD2, or MD3). Specifically, when a change from the normal EV mode MD0 to the custom EV mode (mode MD1, MD2, or MD3) is detected, sound data NF1 notifying that the custom EV mode has started is output from the speaker 16. When a change from the custom EV mode to the normal EV mode MD0 is detected, sound data NF2 notifying that the custom EV mode has ended is output from the speaker 16.

[0065] When switching between custom EV modes is detected, a notification sound based on the switched custom EV mode can be output from the speaker 16. For example, when switching from the custom EV mode (mode MD2) to the custom EV mode (mode MD4) is detected, sound data NF3 notifying that the custom EV mode (mode MD4) has started is output from the speaker 16.

[0066] Fig. 9 is a block diagram showing an example of a functional configuration of the vehicle control device 100 related to output control of a notification sound. In the example shown in Fig. 9, the vehicle control device 100 includes a switching detection unit 150, a notification sound output unit 160, and a notification sound source management unit 170 in addition to the information acquisition unit 110 described in Fig. 6. These functional blocks are realized by, for example, cooperation between the processor 102 and the storage device 104.

[0067] The switching detection unit 150 receives the setting information MOD of the driving mode from the information acquisition unit 110. The switching detection unit 150 detects a switching of the driving mode based on the setting information MOD. When a switching of the driving mode is detected, the switching detection unit 150 identifies the notification sound data NFS to be output to the speaker 16 by referring to the notification sound source management unit 170 using the setting information MOD of the driving mode before and after the switching. When the notification sound data NFS is identified, the switching detection unit 150 transmits it to the notification sound output unit 160.

[0068] The notification sound output unit 160 receives the notification sound data NFS from the switching detection unit 150. Then, the notification sound output unit 160 outputs the notification sound data NFS to the speaker 16.

[0069] The notification sound source management unit 170 stores sound source data of the notification sound. The notification sound source management unit 170 is mainly realized by the storage device 104. Examples of the sound source data of the notification sound include sound data NF1, NF2, and NF3. The sound data NF1 is sound data that notifies that the normal EV mode MD0 has ended and the custom EV mode (mode MD1, MD2, or MD3) has started. The sound data NF2 is sound data that notifies that the custom EV mode (mode MD1, MD2, or MD3) has ended and the normal EV mode MD0 has started. The sound data NF3 is sound data that notifies that a switch has occurred between two types of custom EV modes.

[0070] Sound data NF1 includes, for example, a sound announcing the start of the custom EV mode after switching (e.g., "Entered MT mode", "Entered sound mode"). Sound data NF2 includes, for example, a sound announcing the end of the custom EV mode before switching (e.g., "Exited MT mode", "Exited sound mode"). Sound data NF3 includes, for example, a sound announcing the start of the custom EV mode after switching (e.g., "Entered sound mode", "Entered MT sound mode"). In this way, the content of the sound included in sound data NF1 may be the same as that included in sound data NF3. On the other hand, the content of the sound included in sound data NF1 will never be the same as that included in sound data NF2.

[0071] The sound data NF1, NF2, and NF3 may include a simple notification sound (e.g., a beep). In this case, the sound data NF1 and NF3 may include a fade-in playback sound of a specific sound. On the other hand, the sound data NF2 may include a fade-out playback sound of this specific sound. The fade-in playback sound and the fade-out playback sound are different in tone. Therefore, the playback sound included in the sound data NF1 and NF3 will not be the same as that included in the sound data NF2.

[0072] The sound data NF1, NF2, and NF3 may include engine sounds of an engine vehicle. In this case, the sound data NF1 and NF3 may include engine sounds when the ignition of the engine vehicle is on. On the other hand, the sound data NF2 may include engine sounds when the ignition of the engine vehicle is off. The engine sounds when the ignition is on and the engine sounds when the ignition is off are different in tone. Therefore, the engine sounds included in the sound data NF1 and NF3 will not be the same as those included in the sound data NF2. The sound data NF1 and NF3 may include engine sounds (revving sounds) of an engine vehicle accelerating. On the other hand, the sound data NF2 may include engine sounds of an engine vehicle decelerating.

[0073] When the output control of the pseudo engine sound is performed, the engine sound included in the sound data NF1, NF2, and NF3 may be generated from the sound source data EVSk corresponding to the vehicle model specified by the driver. FIG. 10 is a block diagram showing another example of the functional configuration of the vehicle control device 100 related to the output control of the notification sound. In the example shown in FIG. 10, the switching detection unit 150 identifies the sound source data EVSk (1≦k≦n) corresponding to the vehicle model specified by the driver by referring to the vehicle sound source management unit 120 described in FIG. 7. Then, when the switching of the driving mode is detected, the switching detection unit 150 generates the notification sound data NFS (sound data NFk1, NFk2, or NFk3) from the sound source data EVSk using the setting information MOD of the driving modes before and after the switching. When the notification sound data NFS is generated, the switching detection unit 150 transmits it to the notification sound output unit 160.

[0074] The sound data NFk1 and NFk3 may include an engine sound when the ignition is turned on for the vehicle type specified by the driver. In this case, the sound data NFk2 may include an engine sound when the ignition is turned off for the vehicle type specified by the driver. The sound data NFk1 and NFk3 may include an engine sound (revving sound) during acceleration for the vehicle type specified by the driver. In this case, the sound data NFk2 may include an engine sound during deceleration for an engine vehicle.

[0075] 4-2. Processing example 11 is a flowchart showing the flow of computer processing particularly related to the embodiment. The flowchart shown in FIG. 11 is repeatedly executed by the processor 102 shown in FIG.

[0076] In the routine shown in Fig. 11, first, the setting information MOD is acquired (step S11). The setting information MOD is information on a driving mode designated by the driver. As the driving mode, the four types of modes MD0 to MD3 described in Fig. 8 are exemplified.

[0077] Following the process of step S11, it is determined whether or not a drive mode switch has been detected (step S12). The determination of step S12 is made based on the setting information MOD acquired in the process of step S11. If the determination result of step S12 is positive, the processes of steps S13 and S14 are performed. The processes of steps S13 and S14 are for determining whether or not the drive mode before or after the switch corresponds to the normal EV mode MD0.

[0078] If the determination result of the process of step S13 is positive, it means that the driving mode after the switch corresponds to the custom EV mode (mode MD1, MD2, or MD3). Therefore, if the determination result of the process of step S13 is positive, sound data NF1 notifying that the custom EV mode has started is output to speaker 16. If the determination result of the process of step S14 is positive, it means that the driving mode before the switch corresponds to the custom EV mode. Therefore, if the determination result of the process of step S14 is positive, sound data NF2 notifying that the custom EV mode has ended is output to speaker 16.

[0079] If the determination results of the processes in steps S13 and S14 are both negative, this means that a drive mode switch between two custom EV modes has occurred, and therefore, in this case, sound data NF3 notifying that a switch between custom EV modes has occurred is output to speaker 16.

[0080] Effects According to the embodiment, it is possible to change the output mode of the notification sound from the speaker 16 when switching from the normal EV mode MD0 to the custom EV mode is detected and the notification sound when switching from the custom EV mode to the normal EV mode MD0 is detected. Therefore, it is possible to correctly inform the driver that the custom EV mode has started and ended. This leads to a sense of security when using the custom EV mode, and it is possible to provide the driver with the sensation obtained by driving an engine vehicle in various driving situations. [Explanation of symbols]

[0081] 10...electric vehicle, 12...various sensors, 14...switch, 16...speaker, 22...accelerator pedal, 24...pseudo shift paddle, 27...pseudo shift lever, 28...pseudo clutch pedal, 44...electric motor, 100...vehicle control device, 102...processor, 104...storage device, 110...information acquisition unit, 120...vehicle sound source management unit, 130...engine sound generation unit, 140...sound output control unit, 150...switching detection unit, 160...notification sound output unit, BEV...information about electric vehicle, EGS...engine sound data, EVS...sound source data of engine vehicle, MOD...setting information, NFS...notification sound data, MD0...normal EV mode, MD1 to MD3...custom EV mode, NF1 to NF3...sound data of notification sound

Claims

1. A vehicle control method applied to an electric vehicle that uses an electric motor as a power unit for traveling, comprising: acquiring setting information of a driving mode of the electric vehicle; when a mode switch of the driving mode is detected based on the setting information, outputting a notification sound from a speaker of the electric vehicle to notify a driver of the electric vehicle of the mode switch; Including, the driving mode includes a custom mode in which at least one of an output control of the electric motor based on operation information of a manual driving element of the electric vehicle and an output control of a pseudo engine sound generated based on the operation information is performed; An output form of the notification sound output from the speaker when switching to the custom mode is detected is different from that of the notification sound output from the speaker when switching from the custom mode is detected. A vehicle control method comprising:

2. 2. A vehicle control method according to claim 1, The content of the notification sound output from the speaker when switching to the custom mode is detected is different from the content of the notification sound output from the speaker when switching from the custom mode is detected. A vehicle control method comprising:

3. 2. A vehicle control method according to claim 1, When switching to the custom mode is detected, the notification sound output from the speaker is played back with a fade-in, and when switching from the custom mode is detected, the notification sound output from the speaker is played back with a fade-out. A vehicle control method comprising:

4. 2. A vehicle control method according to claim 1, The notification sound output from the speaker when switching to the custom mode is detected, and the notification sound output from the speaker when switching from the custom mode is detected include an engine sound of a vehicle with a predetermined engine. A vehicle control method comprising:

5. The vehicle control method according to claim 4, the notification sound output from the speaker when switching to the custom mode is detected includes an engine sound generated when an ignition of the specified engine vehicle is turned on, The notification sound output from the speaker when the switching from the custom mode is detected includes an engine sound when the ignition of the specified engine vehicle is turned off. A vehicle control method comprising:

6. The vehicle control method according to claim 4, the notification sound output from the speaker when switching to the custom mode is detected includes an engine sound during acceleration of the specified engine vehicle, The notification sound output from the speaker when the switching from the custom mode is detected includes an engine sound during deceleration of the specified engine vehicle. A vehicle control method comprising:

7. The vehicle control method according to claim 4, The predetermined engine vehicle is selected from a plurality of engine models, The notification sound output from the speaker when switching to the custom mode is detected, and the notification sound output from the speaker when switching from the custom mode is detected include an engine sound of the specified engine model. A vehicle control method comprising:

8. The method according to any one of claims 1 to 7, The manual driving element includes an accelerator pedal and a pseudo shift paddle that resembles a shift paddle of an engine vehicle. A vehicle control method comprising:

9. The method according to any one of claims 1 to 7, The manual driving elements include an accelerator pedal, a pseudo clutch pedal that resembles a clutch pedal of an engine vehicle, and a pseudo shift lever that resembles a shift lever of an engine vehicle. A vehicle control method comprising:

10. A vehicle control device applied to an electric vehicle that uses an electric motor as a power unit for driving, Equipped with a processor that performs various processes, The processor, Acquire setting information of a driving mode of the electric vehicle; When a mode change of the driving mode is detected based on the setting information, a notification sound is output to a speaker of the electric vehicle to notify a driver of the electric vehicle of the mode change; the driving mode includes a custom mode in which at least one of an output control of the electric motor based on operation information of a manual driving element of the electric vehicle and an output control of a pseudo engine sound generated based on the operation information is performed; An output form of the notification sound output from the speaker when switching to the custom mode is detected is different from that of the notification sound output from the speaker when switching from the custom mode is detected. A vehicle control device comprising:

11. An electric vehicle that uses an electric motor as a power unit for traveling, A speaker and A manual driving element; A processor for performing various processes, The processor, Acquire setting information of a driving mode of the electric vehicle; When a mode change of the driving mode is detected based on the setting information, a notification sound is output to the speaker to notify a driver of the electric vehicle of the mode change; The driving mode includes a custom mode in which at least one of an output control of the electric motor based on operation information of the manual driving element and an output control of a pseudo engine sound generated based on the operation information is performed, An output form of the notification sound output from the speaker when switching to the custom mode is detected is different from that of the notification sound output from the speaker when switching from the custom mode is detected. An electric vehicle characterized by

Images