Method of operating main drive of electric vehicle

Abstract

The invention relates to a method (34) for operating a main drive (6) of an electric vehicle (2), in which method a first acceleration value (32) is determined on the basis of a setting (28) of an operating element (14). On the basis of the deviation of the current acceleration (38) from a predetermined maximum acceleration (50), a second acceleration value (56) is determined, and the minimum of the first acceleration value (32) and the second acceleration value (56) is selected as a control value (62). According to the control value (62), the excitation of the main drive (6) is adjusted. Furthermore, the invention relates to a main drive (6) of an electric vehicle (2) and to a computer program product (22).

Description

Technical Field

[0001] The invention relates to a method for operating a main drive of an electric vehicle. Furthermore, the invention relates to a main drive of an electric vehicle and to a computer program product. Background Art

[0002] A motor vehicle has a main drive for propulsion, which acts on one or more wheels of the motor vehicle. If the main drive does not include an internal combustion engine, but only one or more electric motors, these motor vehicles are also called electric vehicles. Usually, electric vehicles include a control element, the setting of which is used to set the current supply to the electric motor (i.e. the main drive). The control element here is, for example, a (gas) handle or a foot pedal. In the case of a relatively rough adjustment of the control element, the main drive is usually arranged in such a way that the main drive transmits an increased torque, thereby accelerating the electric vehicle.

[0003] In order to adapt to the current conditions, the current state of the driver / user of the electric vehicle, or to enhance the driving experience, several driving profiles are usually provided, on the basis of which the electric vehicle is basically set up. Thus, for example, the electric vehicle and the main drive can be moved to a greater degree of sportiness or a greater degree of comfort. For example, a separate driving profile can also be selected for an electric vehicle intended for rental. In addition, for example, different classifications for vehicle insurance can be obtained depending on the specific driving profile settings.

[0004] The maximum achievable speed of an electric vehicle usually varies for different driving profiles, which helps prevent accidents. In addition, the maximum torque provided by the main drive is set according to the selected driving profile, which reduces acceleration. However, once the electric vehicle is driving along a relatively steep road, it may not be able to maintain the current speed due to the reduced maximum torque, or even climb the altitude, although this is technically possible with the help of the main drive. It is also possible that the following road users will hit the electric vehicle due to the sharp drop in speed. Summary of the invention

[0005] The invention is based on the object of specifying a particularly suitable method for operating a main drive of an electric vehicle, a particularly suitable main drive of an electric vehicle and a particularly suitable computer program product, thereby advantageously improving comfort and / or the driving experience and thereby advantageously increasing safety.

[0006] According to the invention, this object is achieved with respect to the method by the features of claim 1, with respect to the master drive by the features of claim 7, and with respect to the computer program product by the features of claim 8. Advantageous further developments and embodiments are subject matter of the dependent claims.

[0007] The main drive is a component of the electric vehicle. In other words, the main drive is particularly suitable for being provided and arranged (installed) in an assembled state as a component of the electric vehicle, wherein the electric vehicle is directly moved by the main drive. Preferably, the electric vehicle is preferably land-moving. The main drive is particularly suitable for, and is provided and arranged to be powered by an on-board power supply of the electric vehicle, which carries a DC voltage of, for example, 12V, 24V or 48V or greater than 100V. For example, the electric vehicle is a passenger car, a truck or a bus. Preferably, the electric vehicle is two-wheeled, for example an electric bicycle, or particularly preferably, the electric vehicle is a motor scooter and is therefore a so-called electric scooter. The main drive comprises an electric motor. In particular, the speed of the electric vehicle depends on the excitation of the electric motor. The electric motor is preferably a brushless DC motor (BLDC) and advantageously a synchronous motor.

[0008] According to the method, a first acceleration value is determined based on the setting of an operating element. The control element is suitable for, in particular intended for and arranged to be operated by a user of the electric vehicle. The operating element is in particular a handle, which is preferably designed to be rotatable. Alternatively, the operating element is, for example, a foot pedal, in particular a so-called accelerator pedal. The control element preferably has a sensor, by means of which the current setting of the control element is detected. By means of the method, a sensor is in particular read, for example, it is a component of the main drive itself. Alternatively, the reading is carried out via an interface of the main transmission device that forms a signal coupling with the sensor.

[0009] For example, the first acceleration value corresponds in particular to an acceleration desired by the user. For example, it is possible to maintain the current speed of the electric vehicle, or to accelerate the electric vehicle, i.e. to change the speed of the electric vehicle. In particular, the amount by which the speed of the electric vehicle is to be changed is also indicated by the first acceleration value (if any). In summary, different first acceleration values ​​are determined for different settings of the control element, wherein in each case the corresponding first acceleration value is functionally related, in particular linearly related, to the acceleration of the electric vehicle desired by the user.

[0010] Furthermore, a second acceleration value is determined based on a deviation of the current acceleration from a specified maximum acceleration. The current acceleration is the actual acceleration of the electric vehicle, i.e. the acceleration currently achieved by the electric vehicle. In particular, the actual value of the current acceleration is determined for this purpose, or at least a value corresponding thereto. The maximum acceleration is predetermined and in particular is static at least for a period of time. For example, the maximum acceleration is also a value of the acceleration or at least a value corresponding thereto.

[0011] The maximum acceleration is in particular specified by a user or another person (e.g. another person in a workshop). For example, the maximum acceleration is independent of the (mechanical and / or electrical) design of the main drive. In particular, the maximum acceleration is lower than the acceleration that is achievable to the greatest extent due to the mechanical / electrical design of the main drive. The second acceleration value is in particular the difference between the maximum acceleration and the current acceleration. Here, in particular, the current acceleration is subtracted from the maximum acceleration, and this value is the second acceleration value. Alternatively, the difference is further processed to obtain the second acceleration value. However, at least the second acceleration value corresponds to the deviation between the current acceleration and the maximum acceleration.

[0012] In a further step, the minimum of the first acceleration value and the second acceleration value is selected as the control value. In other words, it is checked whether the first acceleration value or the second acceleration value is smaller, and in each case the smaller value is used as the control value.

[0013] In a subsequent step, the excitation of the main drive, for example the current, is set according to the control value. For example, the current of the main drive (in particular the current of the electric motor) is adapted and thus changed, or the excitation is not changed, in particular when the control value is zero. However, at least the main drive is operated according to the control value. In particular, in order to adjust the excitation, the already existing excitation (for example the already existing current) is increased or decreased by the control value. In other words, if the user requires, the existing excitation is increased or decreased by the control value, or at least increased or decreased to a value corresponding to the control value, thereby resulting in a change in the speed of the electric vehicle.

[0014] The method thus ensures that the electric vehicle is never operated with an acceleration greater than the specified maximum acceleration. However, there is no current limitation or limitation of the maximum force / torque to be applied by means of the main drive. Therefore, if the electric vehicle is moving along a slope or with a relatively high payload, the same acceleration and thus essentially the same driving behavior are achieved according to the method, which also applies to level roads and low payloads. Therefore, in the case of an upward slope / high payload, an excitation is selected, with which a first acceleration value or a maximum acceleration is achieved. This type of excitation can lead to exceeding the maximum acceleration, for example in the case of a relatively low slope or a low payload. In this case, such an excitation is prevented. Since the excitation / power supply of the main drive is therefore essentially independent of the current load of the electric vehicle, the user can always operate the electric vehicle according to the desired acceleration or maximum acceleration.

[0015] In summary, according to the method, in particular, it is not the current that is limited, but the acceleration. Due to the essentially always identical acceleration, the user's comfort and driving experience are improved. Furthermore, at relatively low maximum accelerations and relatively steep slopes or relatively high payloads, the speed of the electric vehicle can essentially always be maintained or (if necessary) increased, regardless of the type of road surface. As a result, no unexpected or undesired speed reductions can occur, to which, for example, other road users cannot adjust. As a result, rear-end collisions with other road users are prevented and safety is increased.

[0016] Preferably, the main drive comprises a control unit by which the method is at least partially performed. Suitably, the main drive comprises an inverter by which current is supplied to the electric motor, the inverter being set in particular by means of the control unit in dependence on said control value.

[0017] For example, the individual acceleration values, i.e. the first acceleration value and the second acceleration value, are in each case values ​​of acceleration (i.e. m / s^2). However, it is particularly preferred that there is a functional relationship between the individual acceleration values ​​and the values ​​of acceleration. For example, a value of power is used as the corresponding acceleration value. It is particularly preferred that a value of torque is used as the corresponding acceleration value. The control value is therefore also a value of torque. Thus, for example, the first acceleration value, the second acceleration value and / or the control value can be displayed to a user so that he can interpret them. In this way, it is also easier to determine the excitation, for example the current, by which the electric motor is operated. For this purpose, in particular a motor model corresponding to the electric motor used is used. This reduces the effort required to set the excitation.

[0018] For example, the maximum acceleration is specified by the manufacturer of the main drive. This allows, for example, different electric vehicles to always use the same main drive in mechanical terms, but nevertheless achieve different characteristics. However, it is particularly preferred that the specified maximum acceleration is read out from the selected driving profile. In this case, it is convenient to have several driving profiles to choose from, wherein, for example, the maximum acceleration differs between some or all driving profiles. As an alternative or in combination therewith, for example, different maximum speeds of the electric vehicle are stored for different driving profiles.

[0019] For example, the driving profile is stored in a memory which is in particular part of the main drive. Alternatively, the memory is part of a separate component of the electric vehicle, such as an onboard computer. Therefore, the maximum acceleration is read out therefrom according to the method. For example, the driving profile is predetermined by the manufacturer of the electric vehicle and / or the main drive. Alternatively, these driving profiles or at least some of the driving profiles can be modified by the user.

[0020] For example, the user can select a driving profile so that the user can select a driving profile according to the current situation. In this way, comfort and driving experience are further improved. Alternatively, the driving profile is specified by the manufacturer or lessor of the electric vehicle. Thus, for example, different charges can be charged to the user according to the corresponding driving profile.

[0021] For example, the first acceleration value is calculated using a formula. However, it is particularly preferred that the first acceleration value is determined with the aid of a table. Thus, the workload is reduced, and, for example, the table is created only once by the manufacturer of the main drive and is used for all such main drives. In particular, the table is static. Alternatively, the table can also be modified, in particular according to the corresponding driving profile. It is particularly preferred that several tables are available, so that these tables are selected according to the corresponding possible driving profiles. These tables are preferably stored in a public map, wherein the corresponding table is read out from the map according to the possible driving profile. For example, in the case of one of the driving profiles, a relatively high first acceleration value is determined in the case of a low-gear operation of the control element, while in the case of another table (in particular in the case of another driving profile), this first acceleration value is only assigned to a rough operation of the control element. Therefore, flexibility and driving experience are further improved.

[0022] For example, a sensor, in particular an acceleration sensor, is used to determine the current acceleration. The acceleration sensor is, for example, part of the main drive or at least of the electric vehicle and is signal-coupled to the main drive. For example, the sensor is also used for other tasks, which is why no additional hardware is required and therefore no manufacturing costs are increased.

[0023] Alternatively, the current acceleration is determined based on the current speed. In particular, a timing element is used for this purpose and the current speed is fed once directly to a unit and once via the timing element to the unit to generate a difference. In this way, the current acceleration can be determined relatively simply. For example, the current speed is measured with the aid of a sensor associated with a wheel of the electric vehicle. For example, the wheel is driven by a main drive. Alternatively, the wheel is not driven. In this way, for example, if a wheel driven by the main drive rotates, the current acceleration can still be determined relatively accurately.

[0024] Preferably, the current acceleration is determined based on the operating data of the main drive. In particular, the current speed is first determined based on the operating data and the current acceleration is determined therefrom. For this purpose, for example, the current speed is determined based on the voltage applied to the electric motor and / or the current conducted by the electric motor. However, it is particularly preferred that a sensor is assigned to the electric motor, by means of which the operating data are recorded. The sensor is in particular a Hall sensor, by means of which the speed of the electric motor and thus the current speed of the electric motor can be measured, which speed is related to the speed of the electric vehicle as a function of the speed of the electric vehicle.

[0025] For example, the current position of the control element is used as the setting of the control element. In other words, for example, the position in which the control element is located and in which the user holds the control element, in particular against a spring force, is checked. Thus, the user can intuitively create the setting and thereby implicitly create the first acceleration value. Alternatively or in particular sometimes, in conjunction with detecting the above-mentioned position, the rate of change of the position of the control element is detected and used as the setting of the control element. For example, for a larger rate of change, a relatively larger first acceleration value is determined, and for a smaller rate of change, a relatively smaller first acceleration value is determined. Due to the use of the rate of change, for example in an emergency, the required acceleration can be converted relatively quickly as long as the maximum acceleration is not exceeded, thereby further improving safety.

[0026] The main drive is part of an electric vehicle, in particular a land-based electric vehicle, such as a truck (delivery truck), bus or passenger car. It is particularly preferred that the electric vehicle is of single-lane design and is, for example, a motor scooter, motorcycle, electric bicycle or electric moped.

[0027] The main drive comprises an electric motor. The electric motor is, for example, a brushed commutator motor or, particularly preferably, a brushless motor. In particular, the electric motor is a brushless direct current (BLDC) motor. The electric motor preferably comprises several electric coils, which are conveniently divided into several phases. Here, the same number of electric coils is conveniently assigned to each phase. For example, the phases are connected to each other in a delta or star connection. Conveniently, the main drive comprises a unit by means of which current is supplied to the electric motor. The unit preferably comprises a converter, which in particular has a bridge circuit, for example, in particular a B6-circuit. In particular, at least the number of bridge branches corresponds to the number of phases of the electric motor. For example, the drive comprises a gearbox driven by means of the electric motor. The gearbox or the electric motor is particularly suitable for, preferably provided and arranged for, being connected to the wheels of the electric vehicle, so that the wheels are driven directly by means of the electric motor or indirectly via, for example, other components (such as, gearbox).

[0028] The main drive has a control unit which is provided and arranged for, preferably suitable for, performing a method for operating the main drive of an electric vehicle. In the method, a first acceleration value is determined based on the setting of an operating element, and a second acceleration value is determined based on a deviation of the current acceleration from a predetermined maximum acceleration. The minimum of the first acceleration value and the second acceleration value is selected as a control value. An excitation (e.g., current supply) to the main drive (e.g., an electric motor) is set according to the control value.

[0029] The control unit comprises, for example, an application specific circuit (ASIC) or, particularly preferably, a suitably designed programmable computer. In particular, the control unit comprises a storage medium on which a computer program product, also referred to as a computer program, is stored, wherein when the computer program product (i.e., the program) is executed, the computer is caused to perform the method.

[0030] For example, the control element is part of the main drive or is separate from the main drive. In this case, however, the control element is preferably signal-coupled to the main drive in the assembled state, and in particular, the main drive has a corresponding interface for this coupling. In particular, the first determination unit of the control unit is used to determine the first acceleration value.

[0031] For example, the current acceleration is determined by the main drive itself, for which a corresponding sensor is used, in particular, the sensor is a component of the main drive. Alternatively, the main drive forms a signal coupling (signal technology coupling) with such a sensor in the assembled state, and in particular, the main drive has a corresponding interface for this coupling. Suitably, all existing possible interfaces are integrated into a common interface, for example, the common interface meets a bus standard. Preferably, the control unit includes a unit by means of which the maximum acceleration is specified. Conveniently, the control unit includes a second determination unit by means of which the second acceleration value is determined. Preferably, the control unit includes a third determination unit by means of which the selection of the control value is performed, i.e. by means of the third determination unit, the minimum value is determined from the two acceleration values.

[0032] Alternatively or in combination, the control unit comprises a unit by means of which the setting of the current of the main drive is adjusted according to the control value. For example, the control unit comprises a control or regulation of the current for operating the electric motor. For example, the main drive comprises an inverter (if any), by means of which the electric motor is excited, and the regulation of the inverter is carried out by means of the control unit. For example, all units for performing the method, in particular the determination unit, are components of a computer program or are at least partially constructed by discrete components. In other words, these units are provided, for example, by means of software routines or discretely constructed circuits.

[0033] Furthermore, the invention relates to an electric vehicle having such a main drive. In particular, the electric vehicle is a motor scooter or a motorcycle, wherein the propulsion is electric. Alternatively, the electric vehicle is, for example, an electric moped or an electric bicycle. The invention also relates in particular to such a control unit. In particular, the control unit is suitable for, in particular arranged / provided for, carrying out the method.

[0034] The computer program product comprises a plurality of instructions which, when the program (computer program product) is executed by a computer, cause the computer to carry out a method for operating a main drive of an electric vehicle. In the method, a first acceleration value is determined based on the setting of an operating element. A second acceleration value is determined based on a deviation of the current acceleration from a predetermined maximum acceleration. The minimum of the first acceleration value and the second acceleration value is selected as a control value, and the excitation of the main drive is set according to the control value.

[0035] The computer is conveniently part of the control unit and is formed, for example, by means of the control unit. The computer preferably comprises a microprocessor or is formed by means of the microprocessor. The computer program product is, for example, a file or a data carrier containing an executable program which automatically performs the method when installed on a computer.

[0036] The invention also relates to a storage medium having a computer program product stored thereon. Such a storage medium is, for example, a CD-ROM, a DVD or a Blu-ray disc. Alternatively, the storage medium is a USB flash drive or other memory (e.g., rewritable or only writable once). Such a memory is, for example, flash memory, RAM or ROM.

[0037] The further developments and advantages explained for the method also apply mutatis mutandis to the main drive / electric vehicle / control unit / computer program product / storage medium and to one another and vice versa. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In the following, embodiments of the present invention will be explained in more detail with reference to the accompanying drawings, in which:

[0039] Figure 1 is a schematic diagram of an electric vehicle having a main drive,

[0040] Figure 2 A method of operating the main drive is shown, and

[0041] Figure 3 A schematic cross-sectional view of a main drive is shown.

[0042] Corresponding parts are marked with the same reference numerals throughout the Figures. DETAILED DESCRIPTION

[0043] Figure 1 A simplified schematic diagram of an electric vehicle 2 in the form of a scooter is shown. The electric vehicle 2 thus has two wheels 4, one of which is driven by a main drive 6. The main drive 6 comprises an electric motor 8, which is a brushless DC motor (BLDC). By means of the electric motor 8, a gearbox (not shown in detail) is driven, which is operatively connected to one of the wheels 4. The electric motor 8 is driven by means of an on-board power supply which is supplied by a battery 10 providing a 12 V DC voltage.

[0044] The battery 10 is used to power an inverter of the main drive 6, which is not shown in detail and includes a bridge circuit. The inverter itself is regulated by means of a control unit 12 so that the electric motor 8 is supplied with current according to certain specifications. The electric vehicle 2 also includes a control element 14 in the form of a rotatable handle, by means of which an unspecified user can change the settings of the main drive 6. In addition, the electric vehicle 2 includes a selector lever 16, by means of which the electric vehicle 2 can be adjusted according to the preferences of the user. In the example shown, the selector lever 16, the control element 14 and the battery 10 are not components of the drive 6, but are connected to the drive 6, i.e. connected to the drive 6 in terms of signals and / or electricity.

[0045] The control unit (control device) 12 has a computer 18 in the form of a programmable microprocessor. In addition, the control unit 12 includes a storage medium 20 in the form of a memory, on which a computer program product 22 is stored. The computer program product 22 includes a plurality of instructions which, when executed by the computer 18, cause the computer 18 to execute Figure 2 A method 24 is shown for operating the main drive 6 . In other words, the control unit 12 is provided and arranged to perform the method 24 .

[0046] In a first step 26, the setting 28 of the control element 14 is detected. The setting 28 is thus measured by means of a sensor (not shown in detail) of the operating element 14 and transmitted to the main drive 6, i.e. the control unit 12, by means of a signal technology coupling. The setting 28 is the current position of the control element 14, i.e. the position in which the user holds the rotary handle against the spring load. In an alternative embodiment, or when the current position of the control element 14 changes relatively quickly, the rate of change of the position of the control element 14 is used as the setting 28. In general, when the handle is rotated relatively quickly, the rate of change is used as the setting 28, and when the rate of change is below a threshold value, the current position is used as the setting 28.

[0047] According to the setting 28, the first acceleration value 32 is determined by means of a first determination unit 30 of the control unit 12, which is implemented by means of a software routine of the computer program product 20 and is therefore a component of the control unit 12, as in Figure 3 2. For this purpose, the first determination unit 30 uses a table 34 stored in the memory 20, with the help of which different first acceleration values ​​32 are assigned to the various possible different settings 28. In summary, the first acceleration value 32 is determined using the table 34. Here, the first acceleration value 32 is the value of the torque to be applied by means of the electric motor 8 in order to bring the electric vehicle 2 to a certain speed.

[0048] In a second step 36, the current acceleration 38 of the electric vehicle 2 is determined. For this purpose, the current speed 40 is fed once directly to the first unit and once via a timing element 42 to generate a difference 44 by means of which the two values ​​are subtracted from one another. The current speed 40 is thus determined by means of a speed sensor of the electric motor 8 and thus by means of operating data of the main drive 6. Alternatively, the current speed 40 is determined based on the current conducted by the electric motor 8, for example based on artifacts present in the current, such as ripples.

[0049] Furthermore, during the second step 36, it is checked which of a plurality of driving profiles 48 stored in a driving profile memory 46 of the memory 20 has been selected. The driving profiles 48 are selected by the user via the selector lever 16. Predetermined maximum accelerations 50 are associated with the individual driving profiles 48, and these differ between the individual driving profiles 48. In the second step 36, the predetermined maximum accelerations 50 are read out from the selected driving profile 48.

[0050] Said predetermined maximum acceleration 50, which depends on the selected driving profile 48, and the current acceleration 48 are fed to the second unit to generate a difference value 52, by means of which the current acceleration 38 is subtracted from the maximum acceleration 50, and the deviation generated in this way is fed to the second determination unit 54. By means of the second determination unit 54, a second acceleration value 56 is created as a function of the deviation / difference value. In summary, in the second step 36, the second acceleration value 56 is determined based on the deviation of the current acceleration 38 from the predetermined maximum acceleration 50. To this end, by means of the second determination unit 54, a value of a torque corresponding thereto is determined as a function of the value of the acceleration generated by means of the second unit to generate the difference value 52. The value of this torque is used as the second acceleration value 56. In summary, the value of this torque is thus used as the first acceleration value 32 and the second acceleration value 56, respectively.

[0051] In a third step 58, the minimum of the first acceleration value 32 and the second acceleration value 56 is determined by means of the third determination unit 60 and used as the control value 62. In other words, the minimum of the first acceleration value 32 and the second acceleration value 56 is selected as the control value 62. The control value 62 thus corresponds to the torque value by which the torque currently applied by the electric motor 8 is to be changed. If the control element 14 has not been moved, the control value 62 thus corresponds to 0 Nm. If, on the other hand, the user of the control element 14 has turned it and acceleration is to take place, i.e. the setting 28 has been changed, the control value 62 is greater than 0 Nm, wherein the control value 62 does not exceed the torque corresponding to the maximum acceleration 50 specified by means of the selected driving profile 48.

[0052] In a subsequent fourth step 64, the excitation of the main drive 6, i.e. the electric motor 8, is set according to the control value 62. Preferably, an inverter is correspondingly arranged for this purpose. In particular, the existing excitation (e.g., the current) is changed by the control value 62, so that, for example, an increased current is conducted by means of the electric motor 8. The increased current is in particular dimensioned in such a way that, in addition to the previously applied torque, a torque corresponding to the control value 62 is applied by means of the electric motor 8, so that the electric vehicle 2 is accelerated.

[0053] Thus, the acceleration of the electric vehicle 2 is independent of the route of the electric vehicle along the road of travel, including the payload on the electric vehicle 2. Thus, the speed of the electric vehicle 2 can be maintained even if the electric vehicle 2 is relatively heavily loaded or moving along a relatively steep trajectory.

[0054] The present invention is not limited to the above-described embodiments. On the contrary, those skilled in the art may also derive other modifications of the present invention from the embodiments without departing from the purpose of the present invention. In addition, in particular, all individual features described in conjunction with the embodiments may also be combined with each other in other ways without departing from the purpose of the present invention.

[0055] Reference numerals list

[0056] 2 Electric vehicles

[0057] 4 wheels

[0058] 6 Main drive

[0059] 8 Electric Motor

[0060] 10. Battery

[0061] 12 Control Unit

[0062] 14 Control elements

[0063] 16 Selector lever

[0064] 18 Computer

[0065] 20 Memory

[0066] 22 Computer program products

[0067] 24 Methods

[0068] 26 First Step

[0069] 28 Settings

[0070] 30 First determination unit

[0071] 32 First acceleration value

[0072] 34 Table

[0073] 36 Step 2

[0074] 38 Current acceleration

[0075] 40 Current speed

[0076] 42 Timing components

[0077] 44 The first unit for generating the difference

[0078] 46 Driving profile memory

[0079] 48 driving profiles

[0080] 50 Maximum acceleration

[0081] 52 Second unit for generating difference

[0082] 54 Second determination unit

[0083] 56 Second acceleration value

[0084] 58 Step 3

[0085] 60 Third Determination Unit

[0086] 62 Control value

[0087] 64 Step 4

Claims

1. A method (34) for operating a main drive (6) of an electric vehicle (2), wherein - determining a first acceleration value (32) based on a setting (28) of the operating element (14), - determining a second acceleration value (56) based on a deviation of the current acceleration (38) from a predetermined maximum acceleration (50), - selecting the minimum value of the first acceleration value (32) and the second acceleration value (56) as a control value (62), and - setting the excitation of the main drive (6) as a function of the control value (62).

2. The method (24) according to claim 1, It is characterized in that The torque value is used as the acceleration value (32, 56).

3. The method (24) according to claim 1 or 2, It is characterized in that The predetermined maximum acceleration (50) is read from the selected driving profile (48).

4. The method (24) according to any one of claims 1 to 3, It is characterized in that The first acceleration value (32) is determined using a table (34).

5. The method (24) according to any one of claims 1 to 4, It is characterized in that The current acceleration (38) is determined based on operating data of the main drive (8).

6. The method (24) according to any one of claims 1 to 5, It is characterized in that The current position of the operating element (14) and / or the rate of change of the position of the operating element (14) is used as the setting (28) of the operating element (14).

7. A main drive (6) of an electric vehicle (2), the main drive (6) having an electric motor (8) and having a control unit (12), the control unit (12) being provided and arranged to carry out the method (24) according to any one of claims 1 to 6.

8. Computer program product (22), comprising instructions which, when a computer (18) executes the program, cause the computer (18) to perform the method (24) according to any one of claims 1 to 6.

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