Vehicle control system

Abstract

To provide appropriate notifications to the driver in a simulation mode that simulates the driving characteristics of a virtual engine vehicle. [Solution] The vehicle control system is applied to a vehicle equipped with an electric motor as a drive source. In simulation mode, the vehicle control system controls the electric motor to simulate the driving characteristics of a virtual engine vehicle. Specifically, in simulation mode, the vehicle control system calculates the virtual engine output torque of the virtual engine vehicle based on the vehicle's accelerator opening. Furthermore, the vehicle control system controls the electric motor according to the requested torque obtained from the virtual engine output torque. When the notification start condition is met, the vehicle control system starts torque-based notification processing, which superimposes an additional torque component on the requested torque.

Description

Technical Field

[0001] The present disclosure relates to vehicle control technology applied to vehicles equipped with an electric motor as a drive source. In particular, the present disclosure relates to a technology for simulating a virtual engine vehicle in a vehicle equipped with an electric motor as a drive source.

Background Art

[0002] Patent Document 1 discloses an electric vehicle capable of simulating the behavior of a vehicle in a manual transmission (MT) vehicle. The virtual engine rotation speed of the virtual MT vehicle changes according to the operation amount of the accelerator pedal by the driver. When the virtual engine rotation speed becomes equal to or higher than a predetermined threshold value (upper limit rotation speed), the control device simulates fuel cut in a normal MT vehicle, thereby making the driver recognize that the virtual engine rotation speed has reached the upper limit rotation speed. At this time, in order to simulate fuel cut in a normal MT vehicle, the control device automatically reduces the virtual engine output torque by controlling the intake air amount and fuel injection amount of the virtual engine.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Consider an electric vehicle having a simulation mode for simulating the driving characteristics of a virtual engine vehicle. During the simulation mode, a situation may occur where it is desired to notify the driver of something. At this time, it is desirable to appropriately notify the driver.

[0005] As a comparative example, let's consider the technology described in Patent Document 1 mentioned above. According to Patent Document 1, when the virtual engine rotational speed exceeds a predetermined threshold (upper rotational speed), control is performed to make the driver aware of this. Specifically, the control device simulates fuel cut by controlling the intake air volume and fuel injection volume of the virtual engine and automatically reducing the virtual engine output torque. However, the magnitude and frequency of fluctuations (vibrations) in the virtual engine output torque caused by such control depend heavily on the driving environment when calculating the virtual engine output torque. Therefore, depending on the driving environment, the torque vibration required to notify the driver of fuel cut may not be obtained as expected. In other words, depending on the driving environment, the driver may not be notified as intended.

[0006] Furthermore, while Patent Document 1 discloses control when the virtual engine speed exceeds a threshold, it does not disclose anything about control when the virtual engine speed drops significantly. According to Patent Document 1, it is not possible to notify the driver when the virtual engine speed drops significantly. Therefore, there is a risk of engine stalling occurring during the simulation of the virtual engine vehicle.

[0007] One of the purposes of this disclosure is to provide a technology that can appropriately notify the driver in a simulation mode that simulates the driving characteristics of a virtual engine vehicle. [Means for solving the problem]

[0008] The first aspect relates to a vehicle control system applicable to a vehicle equipped with an electric motor as its power source. The vehicle control system comprises one or more processors configured to control an electric motor in a simulation mode to simulate the driving characteristics of a virtual engine vehicle. In simulation mode, one or more processors calculate the virtual engine output torque of a virtual engine vehicle based on the vehicle's accelerator pedal position. Furthermore, one or more processors control the electric motor according to the required torque derived from the virtual engine output torque. If the notification start conditions are met, one or more processors start torque-based notification processing that superimposes an additional torque component on the requested torque.

[0009] The second aspect concerns vehicle control systems applied to vehicles equipped with electric motors as a power source. The vehicle control system comprises one or more processors configured to control an electric motor in a simulation mode to simulate the driving characteristics of a virtual engine vehicle. In simulation mode, one or more processors calculate the virtual engine speed of the virtual engine vehicle. When the virtual engine speed falls below a threshold, one or more processors initiate a notification process to inform the vehicle's driver that the virtual engine speed has fallen below the threshold. [Effects of the Invention]

[0010] From the first perspective, in simulation mode, the electric motor is controlled to simulate the driving characteristics of a virtual engine vehicle. More specifically, the virtual engine output torque of the virtual engine vehicle is calculated based on the vehicle's accelerator opening. Furthermore, the electric motor is controlled according to the required torque obtained from the virtual engine output torque. On the other hand, if the notification start condition is met, an additional torque component is superimposed on the required torque. This additional torque component superimposed on the required torque serves as a notification to the driver. This additional torque component is prepared separately from the virtual engine output torque. In other words, the additional torque component can be arbitrarily set independently of the virtual engine output torque without being affected by the virtual engine output torque. By superimposing such an independent and arbitrary additional torque component on the required torque, it becomes possible to provide the driver with the intended notification regardless of the driving environment. That is, from the first perspective, it becomes possible to provide appropriate notifications to the driver during simulation mode.

[0011] From a second perspective, in simulation mode, the electric motor is controlled to simulate the driving characteristics of a virtual engine vehicle. When the virtual engine speed of the virtual engine vehicle falls below a threshold, a notification process is executed to inform the driver. In this way, the driver is notified that the virtual engine speed has fallen below the threshold. As a result, engine stalling during simulation mode is suppressed. In other words, from a second perspective, it becomes possible to appropriately notify the driver during simulation mode. [Brief explanation of the drawing]

[0012] [Figure 1] This is a conceptual diagram showing a vehicle and its control system. [Figure 2] This is a block diagram showing a basic functional configuration example related to the simulation mode. [Figure 3] This is a conceptual diagram illustrating the overview of the notification process in the simulation mode. [Figure 4] This is a block diagram showing an example of a functional configuration related to notification processing in simulation mode. [Figure 5] It is a block diagram showing a functional configuration example related to notification processing in simulation mode. [Figure 6] It is a flowchart showing a first example of processing related to notification processing in simulation mode. [Figure 7] It is a flowchart showing an example of step-by-step notification processing in simulation mode. [Figure 8] It is a flowchart showing a second example of processing related to notification processing in simulation mode. [Figure 9] It is a flowchart showing a third example of processing related to notification processing in simulation mode. [Figure 10] It is a block diagram showing a functional configuration example related to the first example of torque-based notification processing in simulation mode. [Figure 11] It is a timing chart for explaining the first example of torque-based notification processing in simulation mode. [Figure 12] It is a block diagram showing a functional configuration example related to the second example of torque-based notification processing in simulation mode. [Figure 13] It is a timing chart for explaining the second example of torque-based notification processing in simulation mode. [Figure 14] It is a timing chart for explaining the third example of torque-based notification processing in simulation mode. [Figure 15] It is a block diagram showing a functional configuration example related to the fourth example of torque-based notification processing in simulation mode. [Figure 16] It is a block diagram showing a first configuration example of a power control system for an electric vehicle. [Figure 17] It is a diagram showing examples of an engine model, a clutch model, and a transmission model that constitute an MT vehicle model. [Figure 18] It is a diagram showing the torque characteristics of an electric motor realized by motor control using an MT vehicle model. [Figure 19] It is a block diagram showing a second configuration example of a power control system for an electric vehicle. [Modes for carrying out the invention]

[0013] Embodiments of this disclosure will be described with reference to the attached drawings.

[0014] 1. Vehicles and vehicle control systems Figure 1 is a conceptual diagram showing a vehicle 10 and a vehicle control system 100 according to this embodiment. For example, vehicle 10 is an electric vehicle that uses an electric motor 44 as a drive source for driving. Examples of electric motors 44 include brushless DC motors and three-phase AC synchronous motors. For example, vehicle 10 is a battery electric vehicle (BEV). Other examples include a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), a fuel cell electric vehicle (FCEV), etc.

[0015] The vehicle control system 100 is applied to and controls the vehicle 10. The entire vehicle control system 100 may be mounted on the vehicle 10. As another example, at least a part of the vehicle control system 100 may be contained in a management server outside the vehicle 10. In that case, the vehicle control system 100 may control the vehicle 10 remotely. As yet another example, the vehicle control system 100 may be distributed between the vehicle 10 and the management server.

[0016] Generally speaking, the vehicle control system 100 includes one or more processors 101 (hereinafter simply referred to as processor 101) and one or more storage devices 102 (hereinafter simply referred to as storage devices 102). The processor 101 performs various processes. Examples of processors 101 include general-purpose processors, application-specific processors, CPUs (Central Processing Units), GPUs (Graphics Processing Units), ASICs (Application Specific Integrated Circuits), FPGAs (Field-Programmable Gate Arrays), integrated circuits, conventional circuits, and / or combinations thereof. The processor 101 can also be called circuitry or processing circuitry. Circuitry is hardware programmed to realize the described functions, or hardware that performs those functions. The storage devices 102 store various information. Examples of storage devices 102 include volatile memory, non-volatile memory, HDDs (Hard Disk Drives), SSDs (Solid State Drives), etc. The functions of the vehicle control system 100 are realized through the cooperation of the processor 101 and the memory device 102.

[0017] One or more control programs 103 (hereinafter simply referred to as control program 103) are computer programs executed by a processor 101. The functions of the vehicle control system 100 may be realized through the cooperation of the processor 101 executing the control program 103 and a storage device 102. The control program 103 is stored in the storage device 102. Alternatively, the control program 103 may be recorded on a computer-readable recording medium.

[0018] 2. Simulation Mode The vehicle control system 100 according to this embodiment includes a "simulation mode" that simulates (reproduces) a virtual engine vehicle. The virtual engine vehicle to be simulated is a different type of vehicle from vehicle 10. The virtual engine vehicle to be simulated may be a manual transmission (MT) vehicle.

[0019] For example, in simulation mode, the vehicle control system 100 simulates the driving characteristics of a virtual engine vehicle. In this case, the vehicle control system 100 controls the electric motor 44 of the vehicle 10 to simulate the driving characteristics of a virtual engine vehicle. A specific example of simulating the driving characteristics of a virtual engine vehicle will be explained later in Section 5.

[0020] Figure 2 is a block diagram showing an example of a basic functional configuration related to simulating the driving characteristics of a virtual engine vehicle. The vehicle control system 100 includes a required torque calculation unit 110 and a motor control unit 140.

[0021] The accelerator pedal position Pap is the amount of movement of the accelerator pedal of the vehicle 10 as operated by the driver. The accelerator pedal position Pap is detected by an accelerator position sensor provided on the accelerator pedal of the vehicle 10.

[0022] The virtual engine rotational speed Ne is the rotational speed of the virtual engine assuming that the vehicle 10 is driven by the virtual engine. For example, the virtual engine rotational speed Ne is calculated to increase as the wheel speed of the vehicle 10 increases. The virtual engine rotational speed Ne may also be calculated based on the wheel speed, the overall reduction ratio, and the slip ratio of the virtual clutch. Details of how to calculate the virtual engine rotational speed Ne will be explained in Section 5 below.

[0023] The virtual gear position GP is the gear position in the virtual transmission. If the virtual engine vehicle is a manual transmission vehicle, the vehicle 10 may be equipped with a pseudo-shifter that is manually operated by the driver. In that case, the virtual gear position GP is specified by the driver's operation of the pseudo-shifter.

[0024] The requested torque calculation unit 110 calculates the requested torque Tr, which corresponds to the driving force of the vehicle 10. More specifically, the requested torque calculation unit 110 includes a virtual engine torque map 115. The inputs to the virtual engine torque map 115 include the accelerator opening Pap and the virtual engine rotational speed Ne. The output from the virtual engine torque map 115 is the virtual engine output torque Teout, which is the output torque of the virtual engine. The virtual engine torque map 115 is designed to take the accelerator opening Pap and the virtual engine rotational speed Ne as inputs and output the virtual engine output torque Teout. The virtual engine torque map 115 can be said to be a map that defines the relationship between the accelerator opening Pap, the virtual engine rotational speed Ne, and the virtual engine output torque Teout. The virtual engine torque map 115 is generated in advance and stored in the storage device 102. The requested torque calculation unit 110 uses the virtual engine torque map 115 to calculate the virtual engine output torque Teout according to the accelerator opening Pap and the virtual engine rotational speed Ne.

[0025] Furthermore, the required torque calculation unit 110 calculates the drive wheel torque Tw from the virtual engine output torque Teout, taking into account the virtual gear stage GP, reduction ratio, etc. The drive wheel torque Tw is the torque required for the drive wheels of the vehicle 10. The required motor torque Tm is the motor torque required for the electric motor 44 to achieve the drive wheel torque Tw. By using the reduction ratio from the output shaft of the electric motor 44 to the drive wheels, the drive wheel torque Tw can be converted to the required motor torque Tm. The required torque calculation unit 110 outputs the drive wheel torque Tw or the required motor torque Tm as the required torque Tr.

[0026] The motor control unit 140 controls the electric motor 44 according to the required torque Tr. In this way, the driving characteristics of a virtual engine vehicle are simulated in the vehicle 10.

[0027] As another example, in simulation mode, the vehicle control system 100 may simulate the engine sound of a virtual engine vehicle. The vehicle 10 is equipped with one or more speakers 70 (see Figure 1). The vehicle control system 100 generates a simulated engine sound that simulates the engine sound of a virtual engine vehicle and outputs the simulated engine sound through the speakers 70 of the vehicle 10. For example, the frequency of the simulated engine sound changes in proportion to the virtual engine rotational speed Ne. The sound pressure of the simulated engine sound may also change in proportion to the virtual engine output torque Teout.

[0028] The simulation mode described above allows the driver of vehicle 10 to feel as if they are driving a virtual engine vehicle.

[0029] 3. Driver notification in simulation mode 3-1. Overview During the simulation mode, which simulates a virtual engine vehicle, situations may arise where it is necessary to notify the driver of vehicle 10. For example, if the virtual engine rotation speed Ne becomes too high, there may be a need to notify the driver. Another example is when the virtual engine rotation speed Ne becomes too low, there may be a need to notify the driver. It is desirable that appropriate notifications be provided to the driver of vehicle 10 during the simulation mode.

[0030] The vehicle control system 100 according to this embodiment is configured to notify the driver of the vehicle 10 as needed during the simulation mode. The notification process performed by the vehicle control system 100 during the simulation mode will hereinafter simply be referred to as "notification processing".

[0031] Figure 3 is a conceptual diagram illustrating the overview of the notification processing by the vehicle control system 100 according to this embodiment. Various types of notification processing are possible. Below, three types are given as examples: "torque-based notification processing," "material-based notification processing," and "HMI-based notification processing." The notification processing only needs to include at least one of the "torque-based notification processing," "material-based notification processing," and "HMI-based notification processing."

[0032] Torque-based notification processing is a process that superimposes an "additional torque component Tadd" onto the requested torque Tr for controlling the electric motor 44. As described above, the virtual engine output torque Teout is calculated based on the virtual engine torque map 115, and the requested torque Tr is obtained from this virtual engine output torque Teout. The additional torque component Tadd is prepared separately from the virtual engine output torque Teout. In other words, the additional torque component Tadd can be arbitrarily designed independently of the virtual engine output torque Teout, without being affected by it. Such an independent and arbitrary additional torque component Tadd serves as notification to the driver of the vehicle 10. The additional torque component Tadd may also be a torque oscillation component. The motor control unit 140 controls the electric motor 44 according to the requested torque Tr after the additional torque component Tadd has been superimposed. As the driving force and behavior of the vehicle 10 fluctuate by the amount of the additional torque component Tadd, the driver can recognize the notification from the vehicle control system 100.

[0033] The component-based notification process is a process that vibrates a component 200 mounted on the vehicle 10. Typically, the component 200 is something that comes into contact with the driver of the vehicle 10. For example, the component 200 is the steering wheel operated by the driver. Another example is that the component 200 is the seat on which the driver sits. The vibration of this component 200 serves as a notification to the driver of the vehicle 10. The vibration of the component 200 allows the driver to recognize the notification from the vehicle control system 100.

[0034] HMI-based notification processing is notification processing via an HMI (Human Machine Interface) 300 installed in the vehicle 10. Examples of HMI 300 include displays, touch panels, meters, HUDs (Head-Up Displays), speakers, etc. Visual or audio information is notified to the driver via the HMI 300. This allows the driver to recognize notifications from the vehicle control system 100.

[0035] Figure 4 is a block diagram showing an example of a functional configuration related to notification processing in simulation mode. The vehicle control system 100 further includes a condition determination unit 120 and a notification processing unit 130.

[0036] The condition determination unit 120 determines whether or not the "notification start condition" for performing notification processing is met. The notification start condition is arbitrary. Examples of notification start conditions will be described later. If the notification start condition is met, the condition determination unit 120 instructs the notification processing unit 130 to start notification processing.

[0037] Furthermore, after the notification process has started, the condition determination unit 120 determines whether or not the "notification termination condition" for terminating the notification process is met. The notification termination condition is arbitrary. Examples of notification termination conditions will be described later. If the notification termination condition is met, the condition determination unit 120 instructs the notification processing unit 130 to terminate the notification process.

[0038] The notification processing unit 130 performs notification processing. The notification processing unit 130 includes at least one of the following: torque-based notification processing unit 131, member-based notification processing unit 132, and HMI-based notification processing unit 133.

[0039] The torque-based notification processing unit 131 performs torque-based notification processing. More specifically, the torque-based notification processing unit 131 sets an additional torque component Tadd. The additional torque component Tadd is set independently of the calculation of the requested torque Tr in the requested torque calculation unit 110. In other words, the additional torque component Tadd is prepared separately from the virtual engine output torque Teout. The torque-based notification processing unit 131 sets the additional torque component Tadd without using the virtual engine torque map 115. The additional torque component Tadd may also be a torque oscillation component. For convenience, the requested torque Tr calculated by the requested torque calculation unit 110 is called the basic requested torque Tr0. The torque-based notification processing unit 131 obtains the final requested torque Tr by superimposing the additional torque component Tadd on the basic requested torque Tr0 output from the requested torque calculation unit 110. The motor control unit 140 controls the electric motor 44 according to the requested torque Tr after the additional torque component Tadd has been superimposed.

[0040] The component-based notification processing unit 132 performs component-based notification processing. Specifically, the component-based notification processing unit 132 vibrates the component 200 mounted on the vehicle 10.

[0041] The HMI-based notification processing unit 133 performs HMI-based notification processing. More specifically, the HMI-based notification processing unit 133 notifies the driver of visual or audio information through the HMI 300.

[0042] As described above, according to this embodiment, it is possible to provide notifications to the driver during the simulation mode that simulates an engine-powered vehicle.

[0043] Furthermore, the torque-based notification processing according to this embodiment provides the following additional technical benefits. To explain the technical benefits of the torque-based notification processing according to this embodiment, we first consider the technology described in Patent Document 1 above as a comparative example.

[0044] According to Patent Document 1 mentioned above, when the virtual engine rotational speed Ne exceeds a predetermined threshold (upper rotational speed), control is performed to make the driver aware of this. Specifically, the control device simulates fuel cut by controlling the intake air volume and fuel injection volume of the virtual engine and automatically reducing the virtual engine output torque Teout. However, the magnitude and frequency of fluctuations (vibrations) in the virtual engine output torque Teout due to such control depend heavily on the driving environment when calculating the virtual engine output torque Teout. Therefore, depending on the driving environment, the torque vibration required to notify the driver of fuel cut may not be obtained as expected. In other words, depending on the driving environment, the driver may not be notified as intended.

[0045] On the other hand, according to this embodiment, an additional torque component Tadd is superimposed on the requested torque Tr for controlling the electric motor 44. This additional torque component Tadd superimposed on the requested torque Tr serves as a notification to the driver. This additional torque component Tadd is prepared separately from the virtual engine output torque Teout. In other words, the additional torque component Tadd can be set arbitrarily and independently of the virtual engine output torque Teout, without being affected by the virtual engine output torque Teout. By superimposing such an independent and arbitrary additional torque component Tadd on the requested torque Tr, it becomes possible to provide the driver with the intended notification regardless of the driving environment. That is, according to this embodiment, it becomes possible to provide appropriate notifications to the driver during the simulation mode.

[0046] 3-2. Various Examples of Notification Processing The following describes various examples of notification processing in the simulation mode. In this example, it is assumed that the virtual engine rotation speed Ne and the accelerator opening Pap are input to the condition determination unit 120, as shown in Figure 5.

[0047] 3-2-1. Example 1 Figure 6 is a flowchart showing a first example of the processing related to notification processing in the simulation mode.

[0048] In step S10, the condition determination unit 120 determines whether the driver is pressing the accelerator pedal based on the accelerator pedal opening Pap. If the driver is not pressing the accelerator pedal (step S10; No), the processing for this cycle ends. On the other hand, if the driver is pressing the accelerator pedal (step S10; Yes), the process proceeds to step S100.

[0049] In step S100, the condition determination unit 120 determines whether the first start condition (notification start condition) is met. The first start condition is that the virtual engine rotation speed Ne is equal to or greater than the first operating threshold Ne_Th1. Based on the virtual engine rotation speed Ne, the condition determination unit 120 determines whether the first start condition is met. If the virtual engine rotation speed Ne is less than the first operating threshold Ne_Th1 (step S100; No), the processing for this cycle ends. On the other hand, if the virtual engine rotation speed Ne is equal to or greater than the first operating threshold Ne_Th1 (step S100; Yes), the process proceeds to step S110.

[0050] In step S110, the notification processing unit 130 executes a first notification process. The first notification process is a process to notify the driver of the vehicle 10 that the virtual engine rotation speed Ne has become equal to or greater than the first operating threshold Ne_Th1. The first notification process includes at least one of the following: torque-based notification process, component-based notification process, and HMI-based notification process.

[0051] The first notification process makes it possible to inform the driver, for example, that the virtual engine speed Ne has become too high. This is expected to cause the driver to ease off the accelerator pedal, thereby lowering the virtual engine speed Ne. For example, the first operating threshold Ne_Th1 may be the upper limit of the engine speed assumed for the simulated virtual engine vehicle. In this case, it becomes possible to inform the driver that the virtual engine speed Ne has reached the assumed upper limit.

[0052] In step S120, the condition determination unit 120 determines whether or not the first termination condition (notification termination condition) is met.

[0053] An example of the first termination condition is that the virtual engine rotational speed Ne becomes lower than the first operating threshold Ne_Th1. This is equivalent to the first start condition no longer being met. The condition determination unit 120 determines whether or not this first termination condition is met based on the virtual engine rotational speed Ne.

[0054] Another example of the first termination condition is that a predetermined period of time has elapsed since the start of the first notification process. This predetermined period is, for example, about 1 second.

[0055] Another example of the first termination condition is when the driver stops pressing the accelerator pedal. The condition determination unit 120 determines whether or not this first termination condition is met based on the accelerator pedal opening Pap.

[0056] Step S110 is executed repeatedly until the first termination condition is met. When the first termination condition is met (step S120; Yes), the process proceeds to step S130.

[0057] In step S130, the notification processing unit 130 terminates the first notification process.

[0058] Multiple types of first notification processing may be performed in stages. Figure 7 is a flowchart of an example of staged notification processing. In the example shown in Figure 7, three types of first operating thresholds Ne_Th1 are provided: operating thresholds Ne_Th1A, Ne_Th1B, and Ne_Th1C. Operating threshold Ne_Th1A is higher than operating threshold Ne_Th1B, and operating threshold Ne_Th1B is higher than operating threshold Ne_Th1C. If the virtual engine rotational speed Ne is greater than or equal to operating threshold Ne_Th1C and less than operating threshold Ne_Th1B (step S100C; Yes), torque-based notification processing is performed (step S110C). If the virtual engine rotational speed Ne is greater than or equal to operating threshold Ne_Th1B and less than operating threshold Ne_Th1A (step S100B; Yes), member-based notification processing is performed (step S110B). When the virtual engine rotation speed Ne exceeds the operating threshold Ne_Th1A (step S100A; Yes), HMI-based notification processing is executed (step S110A). In this way, the first notification processing is performed in stages so that the driver can recognize the notification more directly as the virtual engine rotation speed Ne increases.

[0059] Furthermore, the step-by-step first notification process is not limited to the example shown in Figure 7.

[0060] 3-2-2. Second Example Figure 8 is a flowchart showing a second example of the processing related to notification processing in the simulation mode. Step S10 is the same as in the first example above. If the driver is pressing the accelerator pedal (step S10; Yes), the process proceeds to step S200.

[0061] In step S200, the condition determination unit 120 determines whether the second start condition (notification start condition) is met. The second start condition is that the virtual engine rotation speed Ne is less than or equal to the second operating threshold Ne_Th2. The second operating threshold Ne_Th2 is lower than the first operating threshold Ne_Th1 in the first example. Based on the virtual engine rotation speed Ne, the condition determination unit 120 determines whether the second start condition is met. If the virtual engine rotation speed Ne is higher than the second operating threshold Ne_Th2 (step S200; No), the processing for this cycle ends. On the other hand, if the virtual engine rotation speed Ne becomes less than or equal to the second operating threshold Ne_Th2 (step S200; Yes), the process proceeds to step S210.

[0062] In step S210, the notification processing unit 130 executes a second notification process. The second notification process is a process to notify the driver of the vehicle 10 that the virtual engine rotation speed Ne has fallen below the second operating threshold Ne_Th2. The second notification process includes at least one of the following: torque-based notification processing, component-based notification processing, and HMI-based notification processing.

[0063] The second notification process makes it possible to inform the driver, for example, if the virtual engine speed Ne has become too low. This is expected to cause the driver to press the accelerator pedal and increase the virtual engine speed Ne. Since the virtual engine speed Ne is prevented from dropping more than necessary, stalling during the simulation mode is suppressed.

[0064] In step S220, the condition determination unit 120 determines whether or not the second termination condition (notification termination condition) is met.

[0065] An example of a second termination condition is when the virtual engine rotational speed Ne becomes higher than the second operating threshold Ne_Th2. This is equivalent to the second start condition no longer being met. The condition determination unit 120 determines whether or not this second termination condition is met based on the virtual engine rotational speed Ne.

[0066] Another example of a second termination condition is the elapsed time from the start of the second notification process. This predetermined time is, for example, about 1 second.

[0067] Step S210 is repeatedly executed until the second termination condition is met. When the second termination condition is met (step S220; Yes), the process proceeds to step S230.

[0068] In step S230, the notification processing unit 130 terminates the second notification process.

[0069] Similar to the first example described above, multiple types of second notification processes may be performed in stages.

[0070] 3-2-3. Third Example Figure 9 is a flowchart showing a third example of the processing related to notification processing in the simulated mode. The third example is a combination of the first example (Figure 6) and the second example (Figure 8) described above. The second operating threshold Ne_Th2 is lower than the first operating threshold Ne_Th1. According to the third example, both the effects of the first example and the effects of the second example are obtained.

[0071] 4. Various Examples of Torque-Based Notification Processing The following describes various examples of notification processing, particularly torque-based notification processing.

[0072] 4-1. Example 1 Figure 10 is a block diagram showing an example of a functional configuration related to a first example of torque-based notification processing. The vehicle control system 100 includes a requested torque calculation unit 110, a condition determination unit 120, a torque-based notification processing unit 131, and a motor control unit 140.

[0073] The requested torque calculation unit 110 includes a virtual engine torque map 115. Using the virtual engine torque map 115, the requested torque calculation unit 110 calculates a virtual engine output torque Teout corresponding to the accelerator opening Pap and virtual engine rotational speed Ne. Furthermore, the requested torque calculation unit 110 calculates the requested torque Tr from the virtual engine output torque Teout, taking into account the virtual gear stage GP, reduction ratio, etc. For convenience, the requested torque Tr calculated by the requested torque calculation unit 110 is referred to as the basic requested torque Tr0.

[0074] The condition determination unit 120 determines whether or not the first start condition (notification start condition) is met. The first start condition is that the virtual engine rotation speed Ne is equal to or greater than the first operating threshold Ne_Th1. If the first start condition is met, the condition determination unit 120 instructs the torque-based notification processing unit 131 to start torque-based notification processing. After the torque-based notification processing has started, the condition determination unit 120 determines whether or not the first end condition (notification end condition) is met. If the first end condition is met, the condition determination unit 120 instructs the torque-based notification processing unit 131 to terminate torque-based notification processing.

[0075] The torque-based notification processing unit 131 sets the additional torque component Tadd without using the virtual engine torque map 115. The additional torque component Tadd may also be a torque oscillation component. The torque-based notification processing unit 131 obtains the final requested torque Tr by superimposing the additional torque component Tadd on the basic requested torque Tr0 output from the requested torque calculation unit 110.

[0076] The motor control unit 140 controls the electric motor 44 according to the required torque Tr after the additional torque component Tadd has been superimposed.

[0077] Figure 11 is a timing chart illustrating a first example of torque-based notification processing. The horizontal axis represents time, and the vertical axis represents the virtual engine rotational speed Ne or the additional torque component Tadd.

[0078] The driver of vehicle 10 presses down on the accelerator pedal. The virtual engine speed Ne of the virtual engine vehicle increases over time. At time t0, the virtual engine speed Ne reaches the first operating threshold Ne_Th1, and the first start condition is met. Torque-based notification processing begins, and the additional torque component Tadd is superimposed on the requested torque Tr. As a result, the driving force and behavior of vehicle 10 fluctuate by the amount of the additional torque component Tadd. This allows the driver to recognize that the virtual engine speed Ne has become too high. It is then expected that the driver will ease up on pressing the accelerator pedal, causing the virtual engine speed Ne to decrease.

[0079] As illustrated in Figure 11, the additional torque component Tadd may also be a torque oscillation component. That is, the additional torque component Tadd may oscillate to alternate between positive and negative values. The waveform of the torque oscillation component can be set arbitrarily. Because the torque oscillation component is superimposed on the required torque Tr, vibration of the vehicle 10 occurs in accordance with the torque oscillation component. Because the vehicle 10 vibrates, the notification to the driver becomes clearer. The driver can more clearly recognize that the virtual engine rotational speed Ne has become too high.

[0080] The first operating threshold Ne_Th1 may be the upper limit Ne_lim of the engine speed assumed in the simulated virtual engine vehicle. When the required torque calculation unit 110 calculates the basic required torque Tr0, the virtual engine speed Ne may be limited to or less than this upper limit Ne_lim. If the first operating threshold Ne_Th1 is the upper limit Ne_lim, it becomes possible to notify the driver that the virtual engine speed Ne has reached the upper limit Ne_lim. The driver is expected to ease off the accelerator pedal, causing the virtual engine speed Ne to decrease.

[0081] The first operating threshold Ne_Th1 is the upper limit Ne_lim, and the additional torque component Tadd may be a torque oscillation component. In this case, the torque-based notification process makes it possible to simulate vehicle vibration caused by fuel cut. This allows the driver to more clearly recognize that the virtual engine rotation speed Ne has reached the upper limit Ne_lim.

[0082] In the example shown in Figure 11, the additional torque component Tadd is superimposed on the requested torque Tr over a predetermined period T1. The predetermined period T1 is, for example, 1 second. After the predetermined period T1 has elapsed from time t0, the application of the additional torque component Tadd ends. That is, the torque-based notification process ends after the predetermined period T1 has elapsed from the start of the torque-based notification process. This is an example of a first termination condition.

[0083] 4-2. Second Example Figure 12 is a block diagram showing an example of a functional configuration related to a second example of torque-based notification processing. Explanations that overlap with the first example shown in Figure 10 are omitted as appropriate. According to the second example, the accelerator opening Pap is input to the torque-based notification processing unit 131.

[0084] Figure 13 is a timing chart illustrating a second example of torque-based notification processing. Explanations that overlap with the first example shown in Figure 11 are omitted as appropriate. According to the second example, the magnitude of the additional torque component Tadd varies depending on the accelerator opening Pap. More specifically, the higher the accelerator opening Pap, the larger the additional torque component Tadd.

[0085] Figure 13(A) shows the case of strong acceleration with a relatively high accelerator opening Pap. In the case of strong acceleration, the additional torque component Tadd is set to be large. Figure 13(B) shows the case of moderate acceleration with a relatively low accelerator opening Pap. In the case of moderate acceleration, the additional torque component Tadd is set to be smaller than in the case of strong acceleration. In the case of slow acceleration with an even lower accelerator opening Pap, the additional torque component Tadd may be set to zero. In the case of slow acceleration, the virtual engine speed Ne may smoothly converge to the upper limit value Ne_lim, similar to the throttle closing control of a conveyor vehicle.

[0086] Generally speaking, the additional torque component Tadd when the accelerator opening Pap is the first accelerator opening is greater than the additional torque component Tadd when the accelerator opening Pap is the second accelerator opening, which is lower than the first accelerator opening. By setting the additional torque component Tadd while taking the accelerator opening Pap into consideration, it becomes possible to reproduce a more realistic driving feel.

[0087] 4-3. Third Example Figure 14 is a timing chart illustrating a third example of torque-based notification processing. Explanations that overlap with the first example shown in Figure 11 are omitted as appropriate.

[0088] At time t0, the virtual engine speed Ne reaches the first operating threshold Ne_Th1, the first start condition is met, and torque-based notification processing begins. The driver eases off the accelerator pedal. At time tx, the virtual engine speed Ne falls below the first operating threshold Ne_Th1, and the first start condition is no longer met. This time tx is before a predetermined period T1 has elapsed from time t0. In this case, the torque-based notification processing ends at time tx before the predetermined period T1 has elapsed. This is also an example of the first termination condition.

[0089] 4-4. The fourth example Figure 15 is a block diagram showing an example of a functional configuration related to a fourth example of torque-based notification processing. The vehicle control system 100 further includes a gear stage setting unit 150. At the end of the torque-based notification processing, the gear stage setting unit 150 automatically sets the virtual gear stage GP to a predetermined appropriate gear stage, thereby automatically returning the virtual engine rotational speed Ne to an appropriate value.

[0090] In particular, let's consider the case where the first termination condition is "a predetermined period T1 has elapsed since the start of torque-based notification processing." When the first termination condition is met, the torque-based notification processing ends, but at this time, the virtual engine rotational speed Ne is still likely to be above the first operating threshold Ne_Th1. The appropriate gear stage is a predetermined virtual gear stage GP such that the virtual engine rotational speed Ne, which was above the first operating threshold Ne_Th1, becomes lower than the first operating threshold Ne_Th1. When the first termination condition is met, the gear stage setting unit 150 automatically sets the virtual gear stage GP to a predetermined appropriate gear stage. As a result, the virtual engine rotational speed Ne automatically decreases to an appropriate value.

[0091] 5. Specific Examples of Simulation Modes The electric motors used as the power source in conventional electric vehicles (EVs) have significantly different torque characteristics compared to the internal combustion engines used as the power source in conventional vehicles (CVs). Due to these differences in torque characteristics, CVs require a transmission, whereas electric vehicles generally do not. Of course, conventional electric vehicles do not have a manual transmission (MT) that allows the driver to manually switch gear ratios. Therefore, there is a significant difference in driving feel between driving a conventional vehicle with an MT (hereinafter referred to as an MT vehicle) and driving an electric vehicle.

[0092] On the other hand, the torque of an electric motor can be controlled relatively easily by controlling the applied voltage and field. Therefore, with an electric motor, it is possible to obtain the desired torque characteristics within the motor's operating range by implementing appropriate control. Taking advantage of this characteristic, the torque of an electric vehicle can be controlled to simulate the torque characteristics unique to a manual transmission (MT) vehicle. Furthermore, a simulated shifter can be installed in an electric vehicle to allow the driver to experience a driving sensation similar to that of an MT vehicle. In this way, it becomes possible to simulate an MT vehicle in an electric vehicle.

[0093] In other words, the electric vehicle controls the output of the electric motor to simulate the driving characteristics (torque characteristics) unique to a manual transmission (MT) vehicle. The driver operates a simulated shifter to perform a simulated manual gear change. In response to the driver's simulated manual gear change, the electric vehicle changes its driving characteristics (torque characteristics) to simulate an MT vehicle. As a result, the driver of the electric vehicle can get the feeling that they are driving an MT vehicle. The electric motor control mode used to simulate the driving characteristics and manual gear change operation of an MT vehicle will be referred to as "manual mode" or "MT mode" below. Manual mode or MT mode corresponds to "simulation mode".

[0094] The following considers the case where the vehicle 10 related to this disclosure is an electric vehicle equipped with an MT mode. In MT mode, the electric vehicle may generate a simulated engine sound in response to the driver's driving operations and output the simulated engine sound through the speaker 70. Since not only the driving operations of the MT vehicle but also the engine sound of the MT vehicle are reproduced, the satisfaction of drivers seeking realism will be increased. The following describes an example configuration of an electric vehicle equipped with an MT mode. Examples of MT modes include "sequential shift mode" and "3-pedal mode".

[0095] 5-1. First Configuration Example (Sequential Shift Mode) Figure 16 is a block diagram showing a first configuration example of the power control system of an electric vehicle according to this embodiment. The electric vehicle is equipped with an electric motor 44, a battery 46, and an inverter 42. The electric motor 44 is the power unit for driving. The battery 46 stores the electrical energy that drives the electric motor 44. In other words, the electric vehicle is a battery electric vehicle (BEV) that runs on the electrical energy stored in the battery 46. The inverter 42 converts the DC power input from the battery 46 during acceleration into driving power for the electric motor 44. The inverter 42 also converts the regenerative power input from the electric motor 44 during deceleration into DC power and charges the battery 46.

[0096] The electric vehicle is equipped with an accelerator pedal 22 for the driver to input acceleration requests to the electric vehicle. The accelerator pedal 22 is equipped with an accelerator position sensor 32 for detecting the accelerator opening degree.

[0097] The electric vehicle is equipped with a sequential shifter 24. The sequential shifter 24 may be a paddle-type shifter or a lever-type pseudo-shifter.

[0098] The paddle shifters are dummies and not genuine paddle shifters. They have a structure similar to the paddle shifters found on clutchless manual transmission vehicles. The paddle shifters are mounted on the steering wheel. They feature an upshift switch and a downshift switch to determine the operating position. The upshift switch emits an upshift signal 34u when pulled towards the user, and the downshift switch emits a downshift signal 34d when pulled towards the user.

[0099] On the other hand, the lever-type dummy shifter, like the paddle-type shifter, is a dummy that is different from the actual shifter. The lever-type dummy shifter has a structure that resembles the lever-type shifter found in clutchless manual transmission vehicles. The lever-type dummy shifter is configured to output an upshift signal 34u when the shift lever is moved forward, and a downshift signal 34d when the shift lever is moved backward.

[0100] The wheels 26 of the electric vehicle are equipped with wheel speed sensors 36. The wheel speed sensors 36 are used as vehicle speed sensors to detect the vehicle speed of the electric vehicle. In addition, the electric motor 44 is equipped with a rotational speed sensor 38 to detect its rotational speed.

[0101] The electric vehicle is equipped with a control device 50. The control device 50 is included in the vehicle control system 100 described above. The control device 50 is typically an electronic control unit (ECU) installed in an electric vehicle. The control device 50 may be a combination of multiple ECUs. The control device 50 comprises an interface, memory, and a processor. An in-vehicle network is connected to the interface. The memory includes RAM for temporarily recording data and ROM for storing programs and various data related to programs that can be executed by the processor. The program consists of multiple instructions. The processor reads and executes the program and data from memory and generates control signals based on signals obtained from each sensor.

[0102] For example, the control device 50 controls the electric motor 44 by PWM control of the inverter 42. The control device 50 receives signals from the accelerator position sensor 32, the sequential shifter 24 (upshift switch and downshift switch if the sequential shifter 24 is a paddle-type shifter), the wheel speed sensor 36, and the rotational speed sensor 38. The control device 50 processes these signals and calculates a motor torque command value for PWM control of the inverter 42.

[0103] The control device 50 includes two control modes: an automatic mode (EV mode) and a manual mode (MT mode). The automatic mode is the normal control mode for driving the electric vehicle as a typical 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 like a manual transmission vehicle. The manual mode is programmed to change the output characteristics of the electric motor 44 in response to the operation of the accelerator pedal 22 in response to upshift and downshift operations on the sequential shifter 24. This manual mode (MT mode) corresponds to the "sequential shift mode". The automatic mode and manual mode are switchable.

[0104] The control device 50 includes an automatic mode torque calculation unit 54 and a manual mode torque calculation unit 56. Each unit 54 and 56 may be an independent ECU, or it may be an ECU function obtained by executing a program stored in memory on a processor.

[0105] The automatic mode torque calculation unit 54 has a function to calculate the motor torque when the electric motor 44 is controlled in automatic mode. The automatic mode torque calculation unit 54 stores a motor torque command map. The motor torque command map is a map that determines the motor torque from the accelerator opening and the rotational speed of the electric motor 44. Signals from the accelerator position sensor 32 and the rotational speed sensor 38 are input to each parameter of the motor torque command map. The motor torque corresponding to these signals is output from the motor torque command map. Therefore, in automatic mode, even if the driver operates the sequential shifter 24, that operation is not reflected in the motor torque.

[0106] The manual mode torque calculation unit 56 includes an MT vehicle model. The MT vehicle model is a model for calculating the drive wheel torque that should be obtained by operating the accelerator pedal 22 and the sequential shifter 24, assuming that the electric vehicle is an MT vehicle.

[0107] The MT vehicle model provided by the manual mode torque calculation unit 56 will be described with reference to Figure 17. As shown in Figure 17, the MT 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 vehicle model are referred to as the virtual engine, virtual clutch, and virtual transmission, respectively. The engine model 561 models the virtual engine. The clutch model 562 models the virtual clutch. The transmission model 563 models the virtual transmission.

[0108] Engine model 561 calculates the virtual engine speed Ne and virtual engine output torque Teout. The virtual engine speed Ne is calculated based on the wheel rotation speed Nw, the overall reduction ratio R, and the virtual clutch slip ratio Rslip. For example, the virtual engine speed Ne is expressed by equation (1) below. Equation (1): Ne = Nw × R / (1 - Rslip)

[0109] The virtual engine output torque Teout is calculated from the virtual engine rotational speed Ne and the accelerator opening Pap. As shown in Figure 17, a map (virtual engine torque map 115) is used to calculate the virtual engine output torque Teout, which defines the relationship between the accelerator opening Pap, the virtual engine rotational speed Ne, and the virtual engine output torque Teout. This map provides the virtual engine output torque Teout for each accelerator opening Pap relative to the virtual engine rotational speed Ne. The torque characteristics shown in Figure 17 can be set to simulate a gasoline engine, a diesel engine, a naturally aspirated engine, or a turbocharged engine.

[0110] The clutch model 562 calculates the torque transmission gain k. The torque transmission gain k is a gain used to calculate the degree of torque transmission of the virtual clutch according to the virtual clutch opening Pc. The virtual clutch opening Pc is normally 0%, and temporarily opens 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 Figure 17. In this map, the torque transmission gain k is given for the virtual clutch opening Pc. In Figure 17, 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 range from Pc0 to Pc1 and the range from Pc2 to Pc3 are dead zones where the torque transmission gain k does not change with respect to 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 transfer gain k (Tcout = Teout × k).

[0111] Furthermore, clutch model 562 calculates the slip ratio Rslip. The slip ratio Rslip is used to calculate the virtual engine speed Ne in engine model 561. Similar to the torque transmission gain k, a map can be used to calculate the slip ratio Rslip, where the slip ratio Rslip is given to the virtual clutch opening Pc.

[0112] The transmission model 563 calculates the gear ratio (shift ratio) r. The gear ratio r is the gear ratio determined by the virtual gear stage GP in the virtual transmission. The virtual gear stage GP is increased by one step when the sequential shifter 24 is upshifted. Conversely, the virtual gear stage GP is decreased by one step when the sequential shifter 24 is downshifted. The transmission model 563 has a map as shown in Figure 17. In this map, the gear ratio r is assigned to the virtual gear stage GP such that the larger the virtual gear stage GP, the smaller the gear ratio r becomes. The transmission model 563 calculates the transmission output torque Tgout using the gear ratio r obtained from the map and the clutch output torque Tcout. For example, the transmission output torque Tgout is given by the product of the clutch output torque Tcout and the gear ratio r (Tgout = Tcout × r). The transmission output torque Tgout changes discontinuously according to the gear ratio r switching. This discontinuous change in transmission output torque Tgout creates a shift shock, giving the vehicle the feel of having a stepped transmission.

[0113] The MT vehicle model calculates the drive wheel torque Tw using a predetermined reduction ratio rr. The reduction ratio rr is a fixed value determined by the mechanical structure from the virtual transmission to the drive wheels. The value obtained by multiplying the reduction ratio rr by the gear ratio r is the aforementioned overall reduction ratio R. The MT vehicle model calculates the drive wheel torque Tw from the transmission output torque Tgout and the reduction ratio rr. For example, the drive wheel torque Tw is given by the product of the transmission output torque Tgout and the reduction ratio rr (Tw = Tgout × rr).

[0114] The control device 50 converts the drive wheel torque Tw calculated in the MT vehicle model into a required motor torque Tm. The required motor torque Tm is the motor torque required to achieve the drive wheel torque Tw calculated in the MT vehicle model. The reduction ratio from the output shaft of the electric motor 44 to the drive wheels is used to convert the drive wheel torque Tw into a required motor torque Tm. The control device 50 then controls the inverter 42 to control the electric motor 44 according to the required motor torque Tm.

[0115] Figure 18 shows a comparison of the torque characteristics of an electric motor 44 realized by motor control using an MT vehicle model with the torque characteristics of an electric motor 44 realized by normal motor control as an electric vehicle (EV). As shown in Figure 18, motor control using an MT vehicle model can realize torque characteristics (solid line in the figure) that simulate the torque characteristics of an MT vehicle, depending on the virtual gear stage set by the sequential shifter 24. Note that in Figure 18, the number of gear stages is set to 6.

[0116] 5-2. Second Configuration Example (3-Pedal Mode) Figure 19 is a block diagram showing a second configuration example of the power control system of an electric vehicle according to this embodiment. Here, only the configurations that differ from the first configuration example described above will be explained. Specifically, in the second configuration example, the electric vehicle is equipped with a pseudo-shift lever (pseudo-shift device) 27 and a pseudo-clutch pedal 28 instead of the sequential shifter 24 provided in the first configuration example. The pseudo-shift lever 27 and pseudo-clutch pedal 28 are merely dummies and are different from the actual shift lever and clutch pedal.

[0117] The simulated shift lever 27 has a structure that mimics the shift lever found in a manual transmission (MT) vehicle. The placement and feel of the simulated shift lever 27 are equivalent to those of an actual MT vehicle. The simulated shift lever 27 has positions corresponding to each gear, such as 1st, 2nd, 3rd, 4th, 5th, 6th, reverse, and neutral. The simulated shift lever 27 is equipped with a shift position sensor 27a that detects the gear by determining which position the simulated shift lever 27 is in.

[0118] The simulated clutch pedal 28 has a structure that simulates the clutch pedal found in a manual transmission (MT) vehicle. The placement and feel of the simulated clutch pedal 28 are equivalent to those of an actual MT vehicle. The simulated clutch pedal 28 is operated when the simulated shift lever 27 is operated. In other words, the driver depresses the simulated clutch pedal 28 when they want to change the gear setting using the simulated shift lever 27, and releases the pedal when the gear setting change is complete, returning the simulated clutch pedal 28 to its original position. The simulated clutch pedal 28 is equipped with a clutch position sensor 28a for detecting the amount the simulated clutch pedal 28 is depressed.

[0119] The control device 50 receives signals from the accelerator position sensor 32, the shift position sensor 27a, the clutch position sensor 28a, the wheel speed sensor 36, and the rotational speed sensor 38. The control device 50 processes these signals and calculates a motor torque command value for PWM control of the inverter 42.

[0120] The control device 50, similar to the first configuration example described above, includes an automatic mode and a manual mode as control modes. 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 like a manual transmission vehicle. In the manual mode, the output and output characteristics of the electric motor 44 in response to the operation of the accelerator pedal 22 are programmed to change in response to the operation of the simulated clutch pedal 28 and the simulated shift lever (simulated shift device) 27. This manual mode (MT mode) corresponds to the "3-pedal mode". The automatic mode and manual mode are switchable.

[0121] The vehicle model provided by the manual mode torque calculation unit 56 is the same as that shown in Figure 17. However, the virtual clutch opening Pc is replaced by the amount of depression of the pseudo clutch pedal 28 detected by the clutch position sensor 28a. In addition, the virtual gear stage GP is determined by the position of the pseudo shift lever 27 detected by the shift position sensor 27a. [Explanation of symbols]

[0122] 10 vehicles 100 Vehicle control systems 101 Processors 102 Storage device 103 Control Program 110 Required Torque Calculation Unit 115 Virtual Engine Torque Map 120 Condition judgment section 130 Notification Processing Unit 140 Motor Control Unit

Claims

1. A vehicle control system applied to a vehicle equipped with an electric motor as a drive source, In simulation mode, the system includes one or more processors configured to control the electric motor in a manner that simulates the driving characteristics of a virtual engine vehicle. In the simulation mode, the one or more processors Based on the accelerator opening of the aforementioned vehicle, the virtual engine output torque of the virtual engine vehicle is calculated. The electric motor is controlled according to the required torque obtained from the virtual engine output torque. If the notification start condition is met, a torque-based notification process is initiated in which an additional torque component is superimposed on the requested torque. It is configured in such a way Vehicle control system.

2. A vehicle control system according to claim 1, The aforementioned additional torque component is a torque oscillation component. Vehicle control system.

3. A vehicle control system according to claim 2, The torque oscillation component is superimposed on the required torque over a predetermined period of time. Vehicle control system.

4. A vehicle control system according to claim 1, The system further includes one or more storage devices that store a virtual engine torque map defining the relationship between the accelerator opening and the virtual engine output torque. In the simulation mode, the one or more processors By using the virtual engine torque map, the virtual engine output torque corresponding to the accelerator opening is calculated, The additional torque component is set without using the virtual engine torque map. It is configured in such a way Vehicle control system.

5. A vehicle control system according to claim 1, The one or more processors are further configured to terminate the torque-based notification process if a notification termination condition is met after the start of the torque-based notification process. Vehicle control system.

6. A vehicle control system according to claim 5, The notification termination condition is that a predetermined period of time has elapsed since the start of the torque-based notification process. Vehicle control system.

7. A vehicle control system according to claim 5, The notification termination condition is that the notification start condition ceases to be met. Vehicle control system.

8. A vehicle control system according to any one of claims 1 to 7, In the simulation mode, the one or more processors further calculate the virtual engine speed of the virtual engine vehicle. The notification start condition includes the virtual engine rotation speed being equal to or greater than a first operating threshold. Vehicle control system.

9. A vehicle control system according to claim 8, The first operating threshold is the upper limit of the engine speed assumed in the virtual engine vehicle that is being simulated. Vehicle control system.

10. A vehicle control system according to claim 8, The additional torque component when the accelerator opening is the first accelerator opening is greater than the additional torque component when the accelerator opening is the second accelerator opening, which is lower than the first accelerator opening. Vehicle control system.

11. A vehicle control system according to claim 8, The one or more processors further include: When a predetermined period has elapsed since the start of the torque-based notification process, the torque-based notification process is terminated. At the end of the torque-based notification process, the gear position of the virtual engine vehicle is automatically set to a predetermined appropriate gear position. Vehicle control system.

12. A vehicle control system according to any one of claims 1 to 7, In the simulation mode, the one or more processors further calculate the virtual engine speed of the virtual engine vehicle. The notification start condition includes the virtual engine rotation speed being less than or equal to the second operating threshold. Vehicle control system.

13. A vehicle control system according to any one of claims 1 to 7, In the simulation mode, the one or more processors further calculate the virtual engine speed of the virtual engine vehicle. The notification start condition includes the virtual engine rotation speed being equal to or greater than a first operating threshold, or the virtual engine rotation speed being equal to or less than a second operating threshold which is lower than the first operating threshold. Vehicle control system.

14. A vehicle control system applied to a vehicle equipped with an electric motor as a drive source, In simulation mode, the system includes one or more processors configured to control the electric motor in a manner that simulates the driving characteristics of a virtual engine vehicle. In the simulation mode, the one or more processors The virtual engine speed of the aforementioned virtual engine vehicle is calculated, When the virtual engine speed falls below a threshold, a notification process is initiated to inform the vehicle driver that the virtual engine speed has fallen below the threshold. It is configured in such a way Vehicle control system.

15. A vehicle control system according to claim 14, In the simulation mode, the one or more processors Based on the accelerator opening of the aforementioned vehicle, the virtual engine output torque of the virtual engine vehicle is calculated. The electric motor is controlled according to the required torque obtained from the virtual engine output torque. It is configured in such a way, The notification process includes a torque-based notification process that superimposes an additional torque component on the requested torque. Vehicle control system.

16. A vehicle control system according to claim 15, The aforementioned additional torque component is a torque oscillation component. Vehicle control system.

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