JP7459721B2 - Electric vehicle control device - Google Patents

Description

The present invention relates to a control device for an electric vehicle that uses at least a motor as a driving force source.

Patent Document 1 describes an invention related to an electric vehicle using a motor as a driving force source. The electric vehicle described in Patent Document 1 executes torque fluctuation control in which the torque of the drive motor is decreased by a set fluctuation amount and then increased at a predetermined opportunity to produce a pseudo shift change. The predetermined trigger is defined based on, for example, vehicle speed, accelerator opening, and amount of brake depression. According to the electric vehicle described in Patent Document 1, by performing the above-mentioned torque fluctuation control and producing a pseudo shift change, driving that is accustomed to driving a vehicle equipped with a manual transmission is possible. Even when a person drives an electric vehicle that is not equipped with a stepped transmission, it is possible to prevent the driver from feeling uncomfortable.

The electric vehicle described in Patent Document 2, like the electric vehicle described in Patent Document 1 above, executes frequency variation control that changes the inverter carrier frequency by a set variation amount at a predetermined trigger to produce a pseudo-shift change. In the frequency variation control in the electric vehicle described in Patent Document 2, for example, the inverter carrier frequency is reduced to increase the low-pitched noise generated by the motor, and the increased noise produces a pseudo-shift change.

JP 2018-166386 A JP 2018-191366 A

In general, in vehicles that use an engine as a driving force source (engine vehicle), a transmission is used in addition to the engine to change the engine speed and transmit the output torque to the drive wheels. In recent years, automatic transmissions (ATs) that do not require the driver to operate the clutch have become mainstream for engine vehicle transmissions, and manual transmissions (MTs) in which the driver operates the clutch pedal and shift lever to change gears are decreasing. However, MTs have a simpler structure than ATs, and are therefore more reliable and durable. In so-called three-pedal vehicles (MT vehicles) equipped with MTs, the driver can change gears himself and drive the vehicle as intended, resulting in a comfortable driving feel. Therefore, there are still a certain number of users who support three-pedal MT vehicles. Drivers who prefer such three-pedal MT vehicles, or drivers who are accustomed to driving three-pedal MT vehicles, may feel a sense of discomfort or inadequacy when driving a vehicle equipped with an AT, or an electric vehicle such as a hybrid vehicle or an electric vehicle that does not require a transmission, due to the vehicle's behavior and driving sensation being different from that of an MT vehicle. Therefore, in the electric vehicles described in Patent Documents 1 and 2, the torque fluctuation control and frequency fluctuation control described above are performed to produce a pseudo-shift change.

When actually driving a 3-pedal manual transmission vehicle, when changing gears, the driver must not only operate the clutch pedal, but also change the gear by operating the shift lever and adjust the engine speed by operating the accelerator pedal. are being carried out at the same time. In this way, when driving a three-pedal manual transmission vehicle, various driving operations such as clutch operation, shift operation, and accelerator operation (including brake operation in some cases) must be coordinated and timed to match. Is going. Therefore, just by producing a pseudo shift change like the electric cars described in Patent Document 1 and Patent Document 2 mentioned above, it is not enough for drivers who prefer 3-pedal MT cars or those who prefer 3-pedal MT cars to It is impossible to completely eliminate the discomfort and sense of inadequacy that drivers who are accustomed to driving operations feel. For example, in a normal manual transmission vehicle, the engine speed increases depending on the amount of depression of the accelerator pedal, and when the engine speed reaches the upper limit speed (or permissible speed), controls such as fuel cut are executed. This allows the driver to recognize that the upper limit rotation speed has been reached. However, with the configurations of Patent Document 1 and Patent Document 2, the driver does not have a means to recognize that the upper limit rotation speed has been reached, and this may give a sense of discomfort or discomfort to drivers who prefer manual transmission vehicles. Therefore, it is possible to provide a comfortable driving feeling to drivers who prefer 3-pedal MT cars or who are accustomed to driving 3-pedal MT cars without making them feel uncomfortable or lacking. There is still room for improvement in constructing electric vehicles.

This invention was devised with a focus on the above-mentioned technical problem, and an object thereof is to provide a control device for an electric vehicle that can simulate vehicle behavior in a manual transmission vehicle. It is.

In order to achieve the above-mentioned object, the present invention provides a control device for an electric vehicle comprising a driving force source having at least a motor, an accelerator pedal operated by a driver, a clutch pedal operated by the driver, and a shift device operated by the driver, and capable of setting a manual mode in which the torque of the motor is determined in accordance with operation of the clutch pedal and operation of the shift device, the control device further comprising a controller for controlling the vehicle, wherein when the manual mode is set, the controller assumes that a virtual engine is used as the driving force source , the rotation speed of the virtual engine, which changes in accordance with the amount of operation of the accelerator pedal, is calculated based on the rotation speed of an output shaft of the electric vehicle, and when the rotation speed of the virtual engine is equal to or greater than a predetermined threshold value, a predetermined control is executed to reduce the rotation speed of the virtual engine.

The electric vehicle to be controlled in this invention is equipped with a clutch pedal. The clutch pedal is a simulated clutch pedal provided in a so-called three-pedal manual transmission vehicle. By providing such a clutch pedal, the driver can experience a simulated driving operation similar to that of a three-pedal manual transmission vehicle. In particular, the present invention is configured to perform predetermined control in order to make the driver feel that the virtual engine speed has reached a threshold value, which is the upper limit speed. Specifically, when the virtual engine speed reaches a threshold value, a corresponding engine sound (or vibration) is generated to lower the virtual engine speed. It also reduces the output torque. That is, it is configured to simulate a fuel cut that occurs when the engine speed of a normal MT vehicle reaches the upper limit speed. This control allows the driver to experience a driving sensation similar to that of driving a three-pedal manual transmission vehicle. That is, the behavior of an actual MT vehicle can be realistically reproduced.

In addition, by simulating the behavior of the virtual engine in this way, it is possible to reduce the sense of discomfort to drivers who prefer conventional three-pedal manual transmission vehicles or who are accustomed to the driving operations of conventional three-pedal manual transmission vehicles. This makes it possible to provide a comfortable driving feel without causing a feeling of inadequacy.

FIG. 1 is a diagram showing an example of the configuration (drive system and control system) of an electric vehicle to be controlled in the present invention. 4 is a flowchart for illustrating an example of control executed by the control device for an electric vehicle of the present invention.

The embodiment of the present invention will be described with reference to the drawings. Note that the embodiment shown below is merely an example of how the present invention can be realized, and is not intended to limit the present invention.

The vehicle to be controlled in the embodiment of the present invention is an electric vehicle that includes at least one motor as a driving force source. The electric vehicle may be equipped with one or more motors as a driving force source. Alternatively, it may be a so-called hybrid vehicle equipped with an engine and a motor as a driving force source. Regardless of whether the vehicle is an electric vehicle or a hybrid vehicle, torque output from a motor serving as a driving force source is transmitted to drive wheels to generate driving force. The driving force is controlled based on the amount of operation of the accelerator pedal by the driver.

Furthermore, the electric vehicle to be controlled in the embodiment of the present invention is configured to imitate a so-called three-pedal manual transmission vehicle (engine vehicle equipped with a manual transmission equipped with a clutch pedal). That is, even though the electric vehicle that is the object of control in the embodiment of the present invention is an electric vehicle, it is configured so that the driver can experience the same driving operation as a conventional three-pedal manual transmission vehicle. In addition, the applicant of the present application has proposed an invention related to an electric vehicle configured to allow the user to experience driving operations similar to those of such a conventional three-pedal manual transmission vehicle in the application of Japanese Patent Application No. 2020-008926. The electric vehicle control device according to the embodiment of the present invention can basically control the electric vehicle described in detail in the specification of Japanese Patent Application No. 2020-008926.

FIG. 1 schematically shows an example of the configuration (drive system and control system) of an electric vehicle to be controlled in an embodiment of the present invention. An electric vehicle (hereinafter referred to as vehicle) Ve shown in FIG. 1 is an electric vehicle equipped with a motor (MG) 1 as a driving force source. The vehicle Ve includes a drive wheel 2, an accelerator pedal 3, a brake pedal 4, a detection unit 5, a battery (BATT) 6, and a controller (ECU) 7 as main components. Note that the driving force source in the embodiment of the present invention may include one or more motors in addition to the motor 1. Further, it may include a motor 1 and an engine (not shown). Alternatively, it may be a so-called hybrid drive unit that includes the motor 1 and an engine (not shown), as well as a power splitting mechanism, a transmission mechanism, etc. (not shown).

The motor 1 is constituted by, for example, a permanent magnet type synchronous motor or an induction motor. The motor 1 has at least the function of an electric motor that is driven by being supplied with electric power and outputs torque. Further, the motor 1 may function as a generator that generates electric power by being driven by receiving torque from the outside. That is, the motor 1 may be a so-called motor generator that has both the functions of an electric motor and a generator. An inverter 8 is connected to the motor 1 to control the magnitude of the current flowing through the motor 1 and the frequency of the current flowing through each phase. Further, a battery 6 is connected to the inverter 8. Therefore, it is possible to supply the electric power stored in the battery 6 to the motor 1, cause the motor 1 to function as an electric motor, and output driving torque. It is also possible to cause the motor 1 to function as a generator using the torque transmitted from the drive wheels 2, and to store the regenerated power generated at that time in the battery. The output rotation speed and output torque of the motor 1 are electrically controlled by a controller 7, which will be described later. Further, in the case of a motor generator, switching between the function as an electric motor and the function as a generator as described above is electrically controlled.

The driving wheels 2 generate driving force for the vehicle Ve by transmitting the driving torque output from the motor 1. In the embodiment shown in FIG. 1, the drive wheels 2 are connected to a drive power source (ie, the motor 1) via a reduction gear 9, a differential gear 10, and a drive shaft 11. Note that the vehicle Ve in the embodiment of the present invention is a front-wheel drive vehicle that transmits drive torque (output torque of the motor 1) to the front wheels and generates driving force with the front wheels, as in the embodiment shown in FIG. Good too. Alternatively, the vehicle Ve may be a rear wheel drive vehicle that transmits drive torque to the rear wheels via, for example, a propeller shaft (not shown), and generates drive force at the rear wheels. Alternatively, the vehicle Ve may be a four-wheel drive vehicle that is provided with a transfer mechanism (not shown) to transmit driving torque to both the front wheels and the rear wheels, and generate driving force at both the front wheels and the rear wheels. good.

The accelerator pedal 3 is provided as an operating part of an accelerator device (not shown) that generates a driving force for the vehicle Ve in response to the driver's intention to accelerate, and a conventional configuration is used. The accelerator device is operated, for example, by the driver operating an operating part such as the accelerator pedal 3 or an accelerator lever (not shown), and generates a driving force or acceleration for the vehicle Ve. In the embodiment shown in FIG. 1, the accelerator device is configured to generate a driving force or acceleration in response to the driver's depression of the accelerator pedal 3. Specifically, the accelerator device generates a driving force or acceleration that corresponds to the amount of depression (amount of operation) of the accelerator pedal 3.

The brake pedal 4 is provided as an operating part of a brake device (not shown) that generates a braking force for the vehicle Ve, and has a conventional configuration. The brake device is activated by, for example, the driver operating an operating part such as the brake pedal 4 or a brake lever (not shown), and generates a braking force (braking torque) for the vehicle Ve. In the embodiment shown in FIG. 1, the brake device is configured to generate a braking force in response to the driver's depression of the brake pedal 4. For example, the brake device applies brake oil pressure in response to the amount or force of depression of the brake pedal 4, and generates a braking force in response to the brake oil pressure.

The vehicle Ve in the embodiment of the present invention is a driver who prefers a so-called 3-pedal MT vehicle (engine vehicle equipped with a manual transmission equipped with a clutch pedal) or a driver who is accustomed to driving a 3-pedal MT vehicle. In order to meet the needs of customers, it is configured to imitate a three-pedal manual transmission vehicle. For this purpose, the vehicle Ve includes a clutch pedal 12 and a shift lever (shift device) 13.

The clutch pedal 12 is a simulated operation section operated by the driver. The vehicle Ve in the embodiment of the present invention is an electric vehicle and is not equipped with a manual transmission as is provided in conventional engine vehicles. Therefore, the vehicle Ve also does not have a clutch that interrupts power transmission between the engine and the manual transmission. This clutch pedal 12 is not for actually operating a clutch, but is provided in a simulated manner so that even if it is an electric vehicle, you can experience the driving operation of a 3-pedal manual transmission vehicle in a simulated manner. There is. The clutch pedal 12 has a configuration similar to that used in conventional three-pedal manual transmission vehicles. Note that the clutch pedal 12 and the shift lever 13 may be configured to operate in conjunction with each other. In addition, the clutch pedal 12 imitates the system adopted in existing three-pedal manual transmission vehicles, and when the driver depresses the clutch pedal 12 more than a predetermined amount to operate it, the power switch of the vehicle Ve is activated. It may also be configured so that it can be activated.

The shift lever 13 is a simulated operating part operated by the driver. As described above, the vehicle Ve in the embodiment of the present invention is not equipped with a manual transmission such as that provided in a conventional engine vehicle. Therefore, the vehicle Ve does not originally require a shift device for operating a manual transmission. This shift lever 13 is not for actually operating a manual transmission, but is provided as a simulation to allow the driver to virtually experience the driving operation of a three-pedal MT vehicle even in an electric vehicle. The shift lever 13 is provided with a configuration similar to that of a shift lever used in a conventional three-pedal MT vehicle. For example, the shift lever 13 is configured to operate by tracing a shift pattern called an H pattern. The shift lever 13 may also be configured to operate in conjunction with the operation of the clutch pedal 12. For example, the shift lever 13 may be configured to be able to operate when the clutch pedal 12 is depressed to a predetermined operating amount or more. Alternatively, when the shift lever 13 is operated with the clutch pedal 12 being operated less than the predetermined operating amount, it may be configured to simulate a state in which the gears interfere with each other.

The detection unit 5 is a device or device for acquiring various data and information necessary for controlling the vehicle Ve, and includes, for example, a power supply unit, a microcomputer, a sensor, an input/output interface, and the like. In particular, the detection unit 5 in the embodiment of the present invention detects various data related to the operation amount of the accelerator pedal 3, the operation amount of the clutch pedal 12, the operation position of the shift lever 13, and the like. Specifically, the detection unit 5 includes an accelerator pedal sensor 5a that detects the amount of operation of the accelerator pedal 3 by the driver (depression amount, accelerator opening degree, etc.), and an accelerator pedal sensor 5a that detects the amount of operation of the brake pedal 4 by the driver (depression amount, depressing force, etc.). A brake pedal sensor 5b detects the amount of operation of the clutch pedal 12 by the driver (depression amount, depression angle, etc.), a clutch pedal sensor 5c detects the operation position of the shift lever 13 by the driver (for example, the first gear a shift position sensor 5d that detects the speed from gear to sixth gear, reverse gear (R), and neutral (N); a motor rotation speed sensor (or resolver) 5e that detects the rotation speed of the motor 1; It includes a motor torque sensor 5f that detects or calculates torque. In addition, the detection unit 5 includes various sensors such as a vehicle speed sensor (or wheel speed sensor) 5g for detecting the vehicle speed of the vehicle Ve, and an acceleration sensor 5h for detecting the acceleration of the vehicle Ve. ing. The detection unit 5 is electrically connected to a controller 7, which will be described later, and outputs electrical signals according to detected values or calculated values of various sensors, devices, devices, etc. as described above to the controller 7 as detection data. do.

The battery 6 is a power storage device that stores electricity generated by the motor 1, and is connected to the motor 1 so as to be able to send and receive power. Therefore, electricity generated by the motor 1 can be stored in the battery 6. Further, the electric power stored in the battery 6 can be supplied to the motor 1 to drive the motor 1. Note that the power storage device may include an electronic component such as a capacitor in addition to a secondary battery such as a lithium ion battery.

The controller 7 is an electronic control device mainly composed of a microcomputer, for example. In particular, the controller 7 in this embodiment of the present invention mainly controls the operation of the motor 1 via the inverter 8. It also controls the operation of the simulated engine sound generating unit 17 described later. The controller 7 receives various data detected or calculated by the detection unit 5. The controller 7 performs calculations using the various input data and pre-stored data and calculation formulas. The controller 7 outputs the calculation results as a control command signal and controls the inverter 8 and the motor 1. The controller 7 in this embodiment of the present invention hypothetically sets a virtual engine in the calculation process, which is assumed to be used as a driving force source for the vehicle Ve. Although FIG. 1 shows an example in which one controller 7 is provided, multiple controllers 7 may be provided for each device or equipment to be controlled, or for each control content.

The vehicle Ve described above is configured to be able to switch between a normal EV mode (or AT mode) in which the vehicle runs by generating driving force and braking force according to the amount of operation of the accelerator pedal 3 and brake pedal 4 without the driver operating the shift lever 13, and a manual (MT) mode in which the vehicle runs by generating driving force and braking force according to a virtual gear stage according to the position of the shift lever 13 operated by the driver.

The MT mode is a mode in which the vehicle runs while simulating a vehicle equipped with an engine and a manual transmission (hereinafter, also referred to as an MT vehicle). Specifically, the virtual gear can be changed by operating the shift lever 13 while the clutch pedal 12 is depressed, and torque based on the set virtual gear and the amount of operation of the accelerator pedal 3 is output from the motor 1, or a virtual engine speed Ne corresponding to the virtual gear and vehicle speed is calculated, and a sound corresponding to the virtual engine speed Ne is generated from an in-vehicle speaker (e.g., a speaker of an audio device) 14 or other device.

As described above, the vehicle Ve according to the embodiment of the present invention is comfortable for drivers who prefer conventional three-pedal manual transmission vehicles or who are accustomed to driving conventional three-pedal manual transmission vehicles. In order to give you a driving feel, it is designed to simulate the driving operations of a 3-pedal manual transmission vehicle. For this purpose, the controller 7 of this vehicle Ve increases the virtual engine speed (simulated engine speed) according to the amount of depression of the accelerator, and the virtual engine speed is the upper limit speed or the permissible speed. When the rotational speed reaches the upper limit, the driver is configured to experience or recognize that the upper limit rotational speed has been reached.

When the MT mode is set, the vehicle Ve performs torque control using a virtually installed engine as a "virtual engine." Therefore, as shown in FIG. 1, the controller 7 has a virtual engine speed calculation unit 15, a virtual engine output torque calculation unit 16, and a simulated engine sound generation unit 17 as functions related to the control of the motor 1.

The virtual engine rotation speed calculation unit 15 dynamically calculates the rotation speed Ne of the virtual engine based on the driving state while the vehicle Ve is traveling. Specifically, the rotation speed Ne can be obtained from the rotation speed Np of the output shaft (propeller shaft), the gear ratio r corresponding to the shift position of the shift lever 13, and the clutch slip ratio S calculated from the depression amount Pc of the clutch pedal 12. This can be expressed by the following calculation formula.
Ne = Np × (1 / r) × S ... (1)
It is assumed that the kinetic energy that is not used for transmitting torque to the output shaft among the energy output from the engine is used for increasing the virtual engine speed Ne. Therefore, the virtual engine speed Ne may be dynamically calculated based on the equation of motion based on the driving energy.

Further, while the MT vehicle is idling, idle speed control control (ISC control) is executed to maintain the engine rotation speed Ne at a constant rotation speed. Therefore, in consideration of ISC control in the virtual engine, the controller 7, for example, when the shift lever 13 is in the N position and the accelerator opening degree, which is the operation amount of the accelerator pedal 3, is "0", The virtual engine rotation speed Ne is controlled to a predetermined idle rotation speed (for example, about 1000 rpm).

The virtual engine output torque calculation unit 16 calculates the output torque of the virtual engine, for example, from the amount of depression of the accelerator pedal 3 (i.e., the accelerator opening) and the above-mentioned virtual engine rotation speed Ne.

The simulated engine sound generating unit 17 generates an operating sound or vibration that imitates the operating state of the virtual engine. The virtual engine is a virtual internal combustion engine (e.g., a virtual gasoline engine or a virtual diesel engine) assumed to be used as a driving force source for the vehicle Ve, and is hypothetically set in the calculation process of the controller 7. When the rotation speed of the virtual engine varies (is assumed to vary) according to the operation amount (depression amount) of the accelerator pedal 3, the simulated engine sound generating unit 17 generates an operating sound or vibration corresponding to the rotation speed of the virtual engine. For example, the audio device of the vehicle Ve is used to generate the operating sound of the virtual engine from the speaker 14 of the audio device. Alternatively, a dedicated speaker (not shown) or a vibration generating device (not shown) may be provided to generate the operating sound or vibration of the virtual engine. Also, the operating sound of the virtual engine and the vibration may be generated simultaneously in conjunction with each other.

Figure 2 is a flow chart showing an example of control in an embodiment of the present invention, which is configured to allow the driver to feel that the virtual engine speed Ne has reached the upper limit speed, as described above. Note that this control example is executed when the MT mode is set.

First, it is determined whether or not the accelerator is turned on (step S1). As described above, in the embodiment of the present invention, control is performed when the virtual engine rotation speed Ne reaches the upper limit rotation speed, and the virtual engine rotation speed Ne increases according to the amount of depression of the accelerator pedal 3. Therefore, if the accelerator is OFF, a negative determination is made in step S1, and in that case, the routine shown in the flowchart of FIG. 2 is temporarily terminated without executing subsequent control. Note that whether or not the accelerator is turned on is detected by the above-mentioned accelerator pedal sensor 5a.

On the contrary, if the determination in step S1 is affirmative, that is, if the accelerator is turned on, it is determined whether the virtual engine rotation speed Ne is equal to or greater than the threshold value α (step S2). This is a prerequisite step for executing the control in step S3, which will be described later, when the virtual engine speed Ne reaches the threshold value (upper limit speed) α. Therefore, the virtual engine speed Ne has not yet reached the threshold value α. If it has not been reached, a negative determination is made in step S2. Note that the upper limit rotation speed is predetermined depending on the vehicle type, etc., and the threshold value α is not a uniformly determined rotation speed, but a rotation speed within a predetermined tolerance range (allowable rotation speed). good.

In addition, the virtual engine rotation speed Ne can be calculated using the above-mentioned calculation formula, a predetermined map in relation to the vehicle speed, or Calculated from the operation amount of the accelerator pedal 3 (accelerator opening degree). When the clutch is released, that is, when the shift position is neutral, the calculation is based on the accelerator opening. Therefore, if a negative determination is made in this step S3, that is, if the virtual engine speed Ne has not yet reached the threshold value α, the routine shown in the flowchart of FIG. 2 is executed without executing the subsequent control. It will end once.

On the contrary, if the determination in step S2 is affirmative, that is, if the virtual engine speed Ne is equal to or higher than the threshold α, a predetermined control to reduce the virtual engine speed Ne is executed (step S3). . In the case of a normal manual transmission vehicle, when the driver depresses the accelerator pedal 3, the engine speed increases according to the amount of depressing the accelerator pedal 3. In addition, if the engine speed reaches the upper limit speed, in order to protect the engine, the fuel is cut or the electronically controlled throttle is returned to prevent the engine speed from increasing any further. (so-called rev limiter). Thereby, the driver can recognize or feel that the engine speed has reached the upper limit speed.

In contrast, in this embodiment of the invention, the engine is a virtual engine, so even if the accelerator pedal 3 is pressed too hard, no control such as fuel cut is implemented, and the driver does not notice that the virtual engine speed Ne has reached the upper limit. This may cause a sense of discomfort to drivers who are accustomed to driving MT vehicles. Therefore, in this embodiment of the invention, in step S2, when the virtual engine speed Ne has reached the threshold value α, the driver is configured to feel (or recognize) this fact.

Specifically, the operation of fuel cut in an engine is simulated. The content of simulating the fuel cut operation is, for example, by outputting from the speaker 14 an engine sound generated by the simulated engine sound generation section 17 (that is, an engine sound equivalent to simulating a fuel cut when the threshold value α is reached). Further, vibrations of the virtual engine may be generated. Furthermore, vibrations may be generated simultaneously with the operating sound of the virtual engine in conjunction with each other. In addition, the virtual engine rotation speed Ne may be reduced by controlling engine-related parameters such as the intake air amount and fuel injection amount of the virtual engine.

Furthermore, when the clutch is engaged, that is, at a shift position other than neutral (for example, 6th gear), the output torque of the motor 1 is reduced, and the torque transmitted to the drive wheels 2 is reduced. Furthermore, a meter (so-called tachometer provided on the instrument panel) indicating the virtual engine speed Ne is provided, and the meter visually indicates that the engine speed Ne has decreased. Through these controls, the user is made to feel and visually recognize that the virtual engine rotation speed Ne has decreased, that is, that the virtual engine rotation speed Ne has reached the upper limit rotation speed. Note that when the clutch is not engaged and the vehicle is in neutral, no driving force is generated, so the driver feels or recognizes that the virtual engine speed Ne has decreased through the engine sound, vibrations, and meter display.

Next, it is determined whether the virtual engine rotation speed Ne has become equal to or less than a predetermined threshold value β (step S4). This is a prerequisite step for executing the control in step S5, which will be described later, when the virtual engine rotation speed Ne reduced in step S3 becomes equal to or less than the threshold value β. Note that the predetermined threshold value β is lower than the above-mentioned threshold value α, and the difference between these rotational speeds is such that vibrations do not occur frequently due to crossing the rotational speed α and the rotational speed β (for example, 500 rotations). It is. That is, since the difference between the rotational speed α and the threshold value β is relatively small, hysteresis is provided that can suppress the occurrence of continuous vibrations. If a negative determination is made in this step S4, that is, if the virtual engine speed Ne is still greater than the threshold value β, the routine shown in the flowchart of FIG. 2 is temporarily terminated without executing subsequent control. .

On the other hand, if the answer to the question in step S4 is affirmative, that is, if the virtual engine speed Ne is equal to or lower than the threshold value β, normal control is resumed (step S5). As described above, if the virtual engine speed Ne reaches the threshold value α, the torque of the motor 1 is reduced as the virtual engine speed Ne decreases. The vehicle speed also decreases accordingly. On the other hand, in the case of a normal MT vehicle, if the engine speed and vehicle speed decrease and the accelerator pedal 3 is depressed again, the output torque and vehicle speed increase according to the amount of operation of the accelerator pedal 3. Therefore, in step S5, in order to reproduce the behavior of a normal MT vehicle, when the virtual engine speed Ne becomes equal to or lower than the predetermined threshold value β, the virtual engine speed Ne and motor torque are again controlled according to the amount of operation of the accelerator pedal 3.

Specifically, the virtual engine rotation speed Ne is increased and the motor torque is increased. Note that the increase in the virtual engine speed Ne causes the speaker 14 to generate a simulated engine sound as described above. Furthermore, vibrations are generated as the virtual engine rotational speed Ne and torque increase. Furthermore, an increase in the rotational speed Ne of the virtual engine is indicated by a meter indicating the rotational speed Ne of the virtual engine. After the control in step S5 is executed, the routine shown in the flowchart shown in FIG. 2 is temporarily ended.

In this way, in an embodiment of the present invention, when the MT mode is set, a predetermined control is executed to allow the driver to feel that the virtual engine speed Ne has reached the threshold value α, which is the upper limit speed. Specifically, when the virtual engine speed Ne reaches the threshold value α, an engine sound (or vibration) corresponding to the threshold value α is generated to reduce the virtual engine speed Ne. In addition, the output torque is reduced. In other words, it is configured to simulate a fuel cut that occurs when the engine speed Ne of a normal MT vehicle reaches the upper limit speed. This control allows the driver to experience the same driving sensation as if he were driving a three-pedal MT vehicle. In other words, the vehicle behavior of an actual MT vehicle can be realistically reproduced.

In addition, by simulating the behavior of a virtual engine in this way, it is possible to provide a comfortable driving feel to drivers who prefer conventional three-pedal MT vehicles, or drivers who are accustomed to driving conventional three-pedal MT vehicles, without causing them any sense of discomfort or lack.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and may be implemented with appropriate modifications within the scope of the purpose of the present invention. In the above-described embodiment, in order to simulate a fuel cut, the control to reduce the virtual engine speed Ne is configured to execute multiple controls such as a change in the speed of rotation using a simulated engine sound, vibration, or meter display. , at least one of these controls may be executed. Furthermore, the series of control techniques described above can also be applied to, for example, drive simulators for driving lessons, simulation games for entertainment, and the like.

1 Motor (MG)
2 Drive wheel 3 Accelerator pedal 4 Brake pedal 5 Detection unit 6 Battery (BATT)
7 Controller (ECU)
12 Clutch pedal 13 Shift lever 14 Speaker 17 Simulated engine sound generating unit Ve Vehicle (electric vehicle)

Claims (1)

comprising a driving force source having at least a motor, an accelerator pedal operated by a driver, a clutch pedal operated by the driver, and a shift device operated by the driver,
A control device for an electric vehicle that is capable of setting a manual mode that determines the torque of the motor according to the operation of the clutch pedal and the operation of the shift device,
comprising a controller that controls the vehicle;
The controller includes:
Assuming that a virtual engine is used as the driving force source when the manual mode is set,
The rotation speed of the virtual engine that changes according to the operation amount of the accelerator pedal is calculated based on the rotation speed of the output shaft of the electric vehicle,
A control device for an electric vehicle, wherein the control device for an electric vehicle is configured to perform predetermined control to reduce the rotation speed of the virtual engine when the rotation speed of the virtual engine is equal to or higher than a predetermined threshold value.

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