A method for operating an electric vehicle equipped with a device for generating a virtual shift sensation, and an electric vehicle

Abstract

This relates to a method for operating an electric vehicle using a device for generating a virtual shift sensation. [Solution] In a method in which an electric vehicle comprises a drive unit having at least one electric motor 11, and the electric vehicle has a device 13 for generating a virtual shift sensation, when the manual operation mode of the device for generating a virtual shift sensation is activated, in response to the driver's operation of sequential shift elements 17, 18, a virtual shift is performed by the device for generating a virtual shift sensation, where if the first sequential shift element is operated for a period longer than a threshold, a virtual upshift is performed from the current virtual actual driving gear to the highest possible virtual target gear, and when the second sequential shift element is operated for a period longer than a threshold, a virtual downshift is performed from the current virtual actual driving gear to the lowest possible virtual target gear.

Description

TECHNICAL FIELD

[0001] The present invention relates to a method for operating an electric vehicle using a device for generating a virtual shift sensation. Furthermore, the present invention relates to an electric vehicle having a device for generating a virtual shift sensation.

BACKGROUND ART

[0002] Electric vehicles are also referred to as battery electric vehicles. The drive unit of an electric vehicle has at least one electric motor, but no internal combustion engine. In a motor vehicle whose drive unit has an internal combustion engine, a multi-stage manual transmission is connected between the internal combustion engine and the drive output of the motor vehicle, and for efficiency reasons, it is increasingly designed as an automatic transmission. In automatic transmissions, gear changes are carried out automatically in response to the driver's actuation of the accelerator pedal and / or brake pedal. Furthermore, automatic transmissions are known in which gear changes can also be carried out manually on the basis of the driver's actuation of a sequential shift element such as shift paddles.

[0003] In electric vehicles, there is no multi-stage manual transmission between the electric motor and the drive output, and if there is any, there is typically only a reduction transmission with a single fixed transmission ratio or a maximum of two transmission ratios. Gear changes known from motor vehicles having an internal combustion engine and a multi-stage manual transmission are not carried out in electric vehicles. Accordingly, drivers switching from internal combustion engine vehicles to electric vehicles typically feel that the driving experience in electric vehicles lacks sufficient driving feel.

[0004] U.S. Patent Application Publication No. 2021 / 0309112 discloses an electric vehicle having a device for generating a virtual shift sensation.

[0005] German Patent Application Publication No. 10 2022 211 435 discloses another electric vehicle having a device for generating a virtual shift sensation.

PRIOR ART DOCUMENTS

[0006] [Patent Document 1] U.S. Patent Application Publication No. 2021 / 0309112 [Patent Document 2] German Patent Application Publication No. 10 2022 211 435 [Overview of the project] [Problems that the invention aims to solve]

[0007] There is a need to improve the driving experience in electric vehicles. The problem addressed by this invention is to provide a method for operating an electric vehicle together with a device for generating a virtual shift sensation. [Means for solving the problem]

[0008] This operation is solved by the method described in claim 1 and by the automobile described in claim 9. According to the present invention, when the manual operation mode of the device for generating the virtual shift sensation (13) is activated, the device for generating the virtual shift sensation (13) performs virtual shifts in response to the driver's operation of the sequential shift elements (17, 18). If the first sequential shift element (18) is operated for a period longer than a threshold, a virtual upshift is performed from the current virtual actual driving gear to the highest possible virtual target gear, and if the second sequential shift element (17) is operated for a period longer than a threshold, a virtual downshift is performed from the current virtual actual driving gear to the lowest possible virtual target gear. This can further improve the driving experience in electric vehicles. Within the meaning of the present invention, when the device for generating the virtual shift sensation is operated in manual operation mode, virtual shifts are performed in response to the operation of the sequential shift elements, i.e., when each sequential shift element is operated for a period longer than a threshold, from the current virtual actual driving gear to the highest possible virtual target gear or the lowest possible virtual target gear. This makes it possible to provide a particularly responsive and sporty driving experience in electric vehicles where the device for generating a virtual shift sensation operates in manual mode.

[0009] Virtual shifts are preferably suppressed when both the first and second sequential shift elements are activated together and simultaneously for a period longer than a threshold. Furthermore, virtual upshifts to the highest possible virtual gear and virtual downshifts to the lowest possible virtual gear are performed only when the forward driving gear is active and the driving speed is greater than a threshold. This prevents the device for generating virtual shift sensations from performing undesirable virtual shifts to the highest possible virtual gear and the lowest possible virtual gear.

[0010] Preferably, when the device for generating a virtual shift sensation performs a virtual upshift from the virtual actual driving gear to the highest possible virtual gear, the virtual upshift sequence is performed by virtual gear changes one step at a time from the current virtual actual driving gear to the highest possible virtual gear, and when the device for generating a virtual shift sensation performs a virtual downshift from the current virtual actual driving gear to the lowest possible virtual gear, the virtual downshift sequence is performed by virtual gear changes one step at a time from the current virtual actual driving gear to the lowest possible virtual gear. Each virtual shift from the current virtual actual driving gear to the highest possible virtual gear or the lowest possible virtual gear is performed by the device in such a way that it generates a virtual shift sensation as a sequence of continuous single gear shifts between immediately consecutive virtual gears. This means that no virtual intermediate gears are skipped between the current virtual actual driving gear and each virtual target gear. This is particularly preferable to further improve the driving experience in electric vehicles.

[0011] When the automatic operation mode of the device for generating virtual shift sensations is activated, it is preferable that the device generates a virtual automatic shift sensation for generating a virtual shift sensation that performs a virtual shift in response to the driver's operation of the accelerator pedal and / or the driver's operation of the brake pedal. Next, when the automatic operation mode of the device for generating virtual shift sensations is activated, pressing one of the two sequential shift elements stops the automatic operation mode of the device and activates the manual operation mode of the device for generating virtual shift sensations, and the automatic operation mode is restarted after the timer expires. When the device for generating virtual shift sensations is operating in automatic operation mode, this can be used to switch to manual operation mode for a defined period of time and return to automatic operation mode after the timer expires.

[0012] Further preferred configurations of the present invention are disclosed in the dependent claims and the following description. Exemplary embodiments of the present invention will be described in detail with reference to the drawings, but the present invention is not limited thereto. [Brief explanation of the drawing]

[0013] [Figure 1] Figure 1 shows an electric vehicle. [Figure 2] Figure 2 is a block diagram of the electric vehicle assembly. [Modes for carrying out the invention]

[0014] Figure 1 shows an automobile designed as an electric vehicle 10. In the electric vehicle 10, the drive unit has at least one electric motor 11 but does not have an internal combustion engine.

[0015] The drive unit of the electric vehicle 10 has a single electric motor 11 which is capable of driving the axles of the electric vehicle 10.

[0016] The drive unit of the electric vehicle 10 may also be configured to include several electric motors 11. For example, in the case of the two drive axles of the electric vehicle 10, each drive axle may be assigned an individual electric motor 11, in which case the electric vehicle 10 has a configuration with two electric motors 11.

[0017] Each drive wheel of the electric vehicle 10 may also be configured to be assigned an individual electric motor 11, so that the number of electric motors 11 in the drive unit of the electric vehicle 10 corresponds to the number of drive wheels of the electric vehicle 10.

[0018] The number of electric motors 11 in the drive unit of the electric vehicle 10 is merely illustrative.

[0019] Figure 2 shows a highly organized assembly of the electric vehicle 10, that is, the electric motor 11 that supplies drive power to the drive output unit 12 of the electric vehicle 10. In the electric vehicle 10, unlike internal combustion engine-driven automobiles, there is no multi-stage manual transmission between the electric motor 11 and the drive output unit 12, and even if one is present, only a reduction transmission with a single fixed transmission ratio or two transmission ratios is provided at most.

[0020] Therefore, in the electric vehicle 10, gear shifts are not performed, as is known from internal combustion engine automobiles, in response to the driver's operation of the accelerator pedal and / or in response to the driver's operation of the brake pedal of the electric vehicle 10 in a multi-stage manual transmission. This limits the driving experience of the electric vehicle 10.

[0021] To enhance the driving experience of the electric vehicle 10, the electric vehicle 10 according to the present invention is provided with a device 13 for generating a virtual shift sensation.

[0022] As described above, the drive unit of an automobile designed as the electric vehicle 10 has at least one electric motor 11 and no internal combustion engine. The electric vehicle 10 has a traction battery in which electrical energy is stored to operate the at least one electric motor 11. A range extender electric vehicle may be configured in a similar manner using an internal combustion engine for charging the traction battery, but the internal combustion engine is not part of the drive unit of the range extender, since the internal combustion engine does not provide drive power, even though only the at least one electric motor 11 at the drive output unit 12 of the electric vehicle 10 provides drive power. The same applies to fuel cell electric vehicles in which a fuel cell is used to charge the traction battery.

[0023] The device 13 for generating a virtual shift sensation can simulate a virtual transmission with virtual shifting by the device 13 for generating a virtual shift sensation that controls at least one electric motor 11 of the electric vehicle 10, such that the at least one electric motor 11 provides the drive output unit 12 with a torque profile corresponding to the torque profile formed when a gear change is performed in an internal combustion engine-driven vehicle using a multi-stage manual transmission.

[0024] When the device 13 for generating a virtual shift sensation is deactivated, the electric vehicle 10 operates like a conventional electric vehicle without performing virtual shifting.

[0025] On the other hand, when the device 13 for generating a virtual shift sensation of the electric vehicle 10 is activated, it generates a virtual shift sensation for the driver. By doing so, the device 13 for generating a virtual shift sensation can preferably generate either a virtual automatic switching sensation in its first automatic operating mode, or a virtual manual shift sensation in its second manual operating mode.

[0026] In the first automatic operating mode, the device 13 for generating a virtual shift sensation simulates the presence of an automatic multi-stage manual transmission, such that the device 13 performs virtual automatic shifting in response to the driver's operation of the accelerator pedal 14 and / or in response to the driver's operation of the brake pedal 15, and automatically provides the torque curve that can be formed at the drive output unit 12 when a multi-stage manual transmission is present by controlling the electric motor 11 at the drive output unit 12. The torque profile provided to the drive output unit 12 in the automatic operating mode may be configured to be determined in a map-based manner in response to the operation of the accelerator pedal 14 and / or in response to the operation of the brake pedal 15, in particular in accordance with the current virtual actual drive gear and the virtual target gear of the virtual shift.

[0027] On the other hand, when a second manual operation mode of the device 13 for generating a virtual shift sensation is activated, the device 13 generates a virtual manual shift sensation in response to the driver's operation of sequential shift elements 17, 18 mounted on the steering wheel 16 of the electric vehicle, which may be embodied in particular as shift paddles. When the second manual operation mode of the device 13 for generating a virtual shift sensation is active, the device 13 controls the electric motor 11 in response to the driver's operation of the sequential shift elements 17, 18, so that the device 13 provides the drive output unit 12 with a torque curve that would occur if a multi-speed manual transmission operating in sequential shift mode were present in the electric vehicle 10 performing the same virtual sequential shift. The torque curve provided to the drive output unit 12 in manual operation mode may be configured to be determined in the manner of a mapped base in response to the operation of each sequential shift element 17, 18.

[0028] The manual operation mode of the device 13 for generating a virtual shift sensation may also be called the sequential operation mode when a virtual sequential shift is performed in accordance with the operation of each sequential shift element 17, 18. The operation mode of the device 13 for generating a virtual shift sensation may also be called the shift mode.

[0029] The device 13 for generating a virtual shift sensation simulates the presence of a multi-speed manual transmission depending on its operating mode. When the device 13 for generating a virtual shift sensation is activated, it can preferably operate in two operating modes, namely, the first automatic operating mode or the second manual operating mode, as described above. When the device 13 for generating a virtual shift sensation is stopped, the vehicle behaves like a conventional electric vehicle, no virtual shift is simulated, and no virtual shift sensation is provided. On the other hand, when the device 13 for generating a virtual shift sensation is activated, it provides a virtual shift sensation depending on the activated operating mode by performing a virtual shift, and in particular, the device 13 for generating a virtual transmission simulates a virtual transmission by controlling the electric motor 11 to provide a torque curve in the drive output unit 12 that can be formed when gear shifting is performed in a multi-speed manual transmission of an internal combustion engine vehicle.

[0030] The device 13 for generating a virtual shift sensation simulates not only a virtual transmission but also a virtual internal combustion engine, based on virtual engine speed and / or virtual torque, and the virtual shift being performed particularly in automatic shift mode.

[0031] In automatic shift mode, a virtual shift can be performed when a virtual shift point is reached based on the virtual engine speed and / or virtual torque of the virtual internal combustion engine, in response to the driver's operation of the accelerator pedal 14 and / or the driver's operation of the brake pedal 15. This is done in a map-based manner, in particular, via a virtual shift map of the virtual shift strategy.

[0032] The virtual engine speed of the virtual internal combustion engine may be simulated by a device 13 for generating a virtual shift feel, in that the virtual engine speed of the virtual internal combustion engine is calculated on the control side of the drive output unit 12 of the electric vehicle 10 in accordance with a known driving speed or rotational speed, or the rotational speed of the electric motor 11 and the virtual transmission of the engaged virtual gear.

[0033] Depending on the virtual engine speed of the virtual internal combustion engine calculated in this manner, the device 13 for generating a virtual shift sensation may be configured to determine the virtual torque of the virtual internal combustion engine in a map-based or characteristic curve-dependent manner, that is, based on the virtual engine map of the virtual internal combustion engine.

[0034] In automatic shift mode, virtual shifts are performed automatically based on virtual shift points of the virtual shift strategy, which in turn depend on virtual engine speed and / or virtual torque of the virtual internal combustion engine.

[0035] Furthermore, when the device 13 for generating virtual shift sensations is operated in manual operation mode, that is, when the manual operation mode of the device 13 for generating virtual shift sensations is activated, virtual shifts are performed by the device 13 for generating virtual shift sensations in response to the operation of the driver's sequential shift elements 17 and 18. If the first sequential shift element 18 is operated for a period longer than the threshold, a virtual upshift from the current virtual actual driving gear to the highest possible virtual gear is performed as the target virtual gear. On the other hand, if the second sequential shift element 17 is operated for a period longer than the threshold, a virtual downshift from the current virtual actual driving gear to the lowest possible virtual gear is performed as the target virtual gear. If the first sequential shift element 18 is operated for a period shorter than the threshold, a virtual upshift of one virtual gear at a time is performed, and if the second sequential shift element 17 is operated for a period shorter than the threshold, a virtual downshift from the current virtual actual driving gear of one virtual gear at a time is performed.

[0036] Only when the forward driving gear D is active as the driving mode of the electric vehicle 10 and the current driving speed is greater than the threshold, a virtual upshift to the highest possible gear and a virtual downshift to the lowest possible gear are performed in accordance with the operation of the respective sequential shift elements 17 and 18. Therefore, when the reverse driving gear R or neutral gear N is active as the driving mode of the electric vehicle 10, no virtual shift to the highest possible virtual gear or the lowest or smallest possible virtual gear occurs in accordance with the driver's operation of the sequential shift elements 17 and 18. Even when the forward driving gear D is active but the driving speed is lower than the threshold, no virtual upshift to the highest possible virtual gear and no virtual downshift to the lowest possible virtual gear are performed.

[0037] Furthermore, when both the first sequential shift element 18 and the second sequential shift element 17 are activated simultaneously and together for a longer period than the threshold, the virtual shift is suppressed and therefore not performed. This helps prevent undesirable virtual gear changes, whether the virtual gear change is performed by a single virtual gear or by a virtual gear change with the largest possible number of virtual gears to reach the highest possible virtual gear or the lowest possible virtual gear.

[0038] Furthermore, if a virtual shift-up from the current virtual actual driving gear to the highest possible virtual gear is performed due to the activation of the first sequential shift element 18 for a period longer than the threshold, a sequence of virtual shift-ups of one virtual gear at a time is performed from the current virtual actual driving gear to the highest possible virtual gear. Therefore, if a virtual shift-up is performed from the current virtual actual driving gear 3 to the highest possible target virtual gear 7, individual virtual shift sequences are performed from virtual gear 3 to virtual gear 4, from virtual gear 4 to virtual gear 5, and from virtual gear 5 to virtual gear 7.

[0039] Similarly, if a virtual downshift is performed from the current virtual actual driving gear to the lowest possible target virtual gear, a sequence of virtual upshifts of one virtual gear at a time will be performed from the current virtual actual driving gear to the lowest possible virtual gear. If a virtual shift is performed from the current virtual gear 8 to the lowest possible virtual target gear 3, the individual sequences of virtual shifts will be performed from virtual gear 8 to virtual gear 7, from virtual gear 7 to virtual gear 6, from virtual gear 6 to virtual gear 5, from virtual gear 5 to virtual gear 4, and from virtual gear 4 to virtual gear 3.

[0040] Each of the highest possible virtual gears and each of the lowest possible virtual gears is determined according to the current travel speed of the electric vehicle 10, and / or according to the current longitudinal acceleration of the electric vehicle 10, and according to the current virtual actual travel gear, preferably according to the current virtual engine speed.

[0041] For each current driving condition, the highest possible current virtual driving gear and the lowest possible currently available virtual gear can be determined according to the current virtual actual driving gear, the current driving speed, and the current longitudinal acceleration, preferably the current virtual engine speed, and in particular according to the virtual shift map stored in the device 13.

[0042] Virtual shift points are defined for each individual gear within the virtual shift map, and as a result, a shift is triggered and executed when the shift point is reached. These shift maps may also depend on a selected driving mode, such as Eco mode and / or Range mode and / or Sport mode and / or Performance mode and / or Race mode.

[0043] In response to the operation of the sequential shift elements 17 and 18, the execution of the virtual shift described above occurs when the manual operation mode of the device 13 for generating the virtual shift sensation is activated. When the automatic operation mode of the device for generating the virtual shift sensation is activated, the virtual shift is automatically performed by the device 13 to generate the virtual shift sensation in response to the driver's operation of the accelerator pedal 14 and / or the driver's operation of the brake pedal 15.

[0044] In this context, when the automatic shift mode of the device 13 for generating virtual shift sensations is activated, activating one of the two sequential shift elements for a defined period of time may be provided to cause a change from automatic operation mode to manual operation mode, followed by a return to automatic operation mode. Therefore, when the automatic operation mode of the device 13 for generating virtual shift sensations is activated, if one of the two sequential shift elements 17, 18 is activated for a period longer than a defined threshold but particularly shorter than a threshold for whether a virtual shift to the highest possible virtual gear or the lowest possible virtual gear is performed in manual operation mode, the automatic shift mode is stopped and manual operation mode is activated, but after a timer that is started when the shift from automatic operation mode to manual operation mode has elapsed, the automatic operation mode is automatically restarted. When such a change to manual operation mode is made, the configuration may be such that the change to the highest possible virtual gear or the lowest possible virtual gear is performed as described above.

[0045] The present invention relates to an electric vehicle having a drive unit comprising at least one electric motor 11 and a device 13 for generating a virtual shift sensation, wherein the device 13 for generating a virtual shift sensation is designed to carry out the method described above.

[0046] The device 13 for generating a virtual shift sensation automatically executes the method according to the present invention on the control side, in particular, in accordance with the switching mode selected by the driver, and / or the drive mode selected by the driver, and / or the driver's operation of the accelerator pedal 14 and / or the brake pedal 15, and / or the driver's operation of the respective sequential shift elements 17, 18.

[0047] The device 13 for generating a virtual shift sensation is configured to perform a virtual shift from the current virtual actual driving gear to the highest possible virtual gear or the lowest possible virtual gear, depending on the driver's operation of the sequential shift elements 17 and 18 in active manual operation mode, i.e., when each sequential shift element 17 and 18 is operated for a period longer than a threshold. This can further improve the driving experience in electric vehicles. [Explanation of Symbols]

[0048] 10 Electric vehicles 11 Electric motor 12 Drive output section 13. Device for generating virtual shifts 14. Accelerator pedal 15 Brake pedal 17 Sequential Shift Elements 18 Sequential Shift Elements

Claims

1. A method for operating an electric vehicle (10), The electric vehicle (10) comprises a drive unit having at least one electric motor (11), In a method in which the electric vehicle (10) has a device (13) for generating a virtual shift sensation, When the manual operation mode of the device (13) for generating the virtual shift sensation is activated, the device (13) for generating the virtual shift sensation generates a virtual shift in response to the driver's operation of the sequential shift elements (17, 18). If the first sequential shift element (18) is activated for a period longer than the threshold, a virtual upshift is performed from the current virtual actual driving gear to the highest possible virtual gear as the virtual target gear. A method characterized in that when a second sequential shift element (17) is operated for a period longer than a threshold, a virtual downshift is performed from the current virtual actual driving gear to the lowest possible virtual gear as a virtual target gear.

2. The method according to claim 1, characterized in that virtual shift is suppressed when both the first sequential shift element and the second sequential shift element (17, 18) are operated together for a period longer than a threshold.

3. The method according to 1 or 2, characterized in that a virtual upshift to the highest possible virtual gear and a virtual downshift to the lowest possible virtual gear are performed only when the forward driving gear is active and the driving speed is greater than a threshold.

4. If a virtual upshift from the current virtual actual driving gear to the highest possible virtual gear is performed, a sequence of virtual upshifts of one virtual gear at a time will be executed from the current virtual actual driving gear to the highest possible virtual gear. The method according to any one of claims 1 to 3, characterized in that, when a virtual downshift is performed from the current virtual actual driving gear to the lowest possible virtual gear, a sequence of virtual downshifts of one virtual gear at a time is performed from the current virtual actual driving gear to the lowest possible virtual gear.

5. If the first sequential shift element (18) is operated for a period shorter than the threshold, a virtual upshift of one virtual gear at a time is performed. The method according to any one of claims 1 to 4, characterized in that when the second sequential shift element (17) operates for a period shorter than a threshold, a virtual downshift of one virtual gear at a time is performed from the current virtual actual driving gear.

6. The method according to any one of claims 1 to 5, characterized in that the highest possible virtual gear and the lowest possible virtual gear are determined according to the current running speed of the electric vehicle and / or the current longitudinal acceleration of the electric vehicle.

7. The method according to any one of claims 1 to 6, characterized in that when the automatic operation mode of the device (13) for generating the virtual shift sensation is activated, a virtual automatic shift sensation is generated by the device (13) for generating the virtual shift sensation executing a virtual shift in response to the operation of the driver's accelerator pedal (14) and / or the operation of the driver's brake pedal (15).

8. The method according to claim 7, characterized in that, when the automatic operation mode of the device (13) for generating the virtual shift sensation is activated, the automatic operation mode of the device (13) for generating the virtual shift sensation is stopped by activating one of the two sequential shift elements (17, 18), the manual operation mode of the device (13) for generating the virtual shift sensation is activated, and the automatic operation mode is activated again after the timer has elapsed.

9. An electric vehicle (10), The drive unit has at least one electric motor (11), In an electric vehicle (10) having a device (13) for generating a virtual shift sensation, When the manual operation mode of the device (13) for generating the virtual shift sensation is activated, the device (13) for generating the virtual shift sensation will operate in accordance with the driver's operation of the sequential shift elements (17, 18). If the first sequential shift element (18) is activated for a period longer than the threshold, a virtual upshift is performed from the current virtual actual driving gear to the highest possible virtual gear as the virtual target gear. An electric vehicle (10) characterized in that when a second sequential shift element (17) is operated for a period longer than a threshold, a virtual downshift is performed from the current virtual actual driving gear to the lowest possible virtual gear as a virtual target gear.

10. The electric motor (10) according to claim 9, characterized in that the device (13) for generating the virtual shift sensation is set up to carry out the method described in any one of claims 1 to 8.

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