# US 11,897,472 B2 · Method for controlling a drive motor in a motor vehicle > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,897,472 B2 - Document ID: US11897472B2 - Status: Granted - Kind: B2 - Application number: 16/383,859 - Filed: 2019-04-15 - Published: 2019-11-07 - Granted: 2024-02-13 - Earliest claimed: 2018-05-07 - Assignees: Audi AG - Applicants: Audi AG - Inventors: Clemens Burow; Jürgen Bader; Moritz Reiff; Raphael Kis; Siegfried Pint - Web page: https://patentgrep.com/patent/US11897472B2 ## CPC - B60W 30/18172: {Preventing, or responsive to skidding of wheels} - B60K 28/16: responsive to, or preventing, spinning or skidding of wheels - F02D 31/001: {Electric control of rotation speed} - F02D 41/021: {Introducing corrections for particular conditions exterior to the engine (conjoint control of vehicle sub-units for propelling the vehicle B60W30/18)} - B60W 2520/10: Longitudinal speed - B60W 2520/26: Wheel slip - B60W 2520/28: Wheel speed - B60W 2552/40: Coefficient of friction - B60W 2710/0644: Engine speed - B60W 2710/0666: Engine torque - B60W 2710/081: Speed - B60W: CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT - B60K: ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES - F02D: CONTROLLING COMBUSTION ENGINES (vehicle fittings, acting on a single sub-unit only, for automatically controlling vehicle speed B60K31/00; conjoint control of vehicle sub-units of different type or different function, road vehicle drive control systems for purposes other than the control of a single sub-unit B60W) ## Abstract A method for controlling a drive motor in a motor vehicle may include the steps: determining driving situation information which describes a static friction and/or a frictional connection of at least one wheel of the motor vehicle and/or a speed of the motor vehicle, determining a minimum speed of the drive motor as a function of the driving situation information, and regulating or controlling the speed of the drive motor as a function of the minimum speed, in particular such that the speed is always greater than the minimum speed. ## Claims ### Claim 1 A method for controlling a drive motor in a motor vehicle, comprising: determining driving situation information which describes a static friction and a frictional connection of at least one wheel of the motor vehicle with a road surface and a speed of the motor vehicle, determining a minimum speed of the drive motor as a function of the driving situation information based on at least one traction-slip curve describing a relationship between wheel slip of the at least one wheel of the motor vehicle and an actual traction value for a specific driving condition based on weather conditions and the road surface, wherein the at least one traction-slip curve includes a maximum slip point below which the driving situation is considered stable and above which the driving situation is considered unstable; monitoring, via a first speed sensor, an actual speed of an output shaft to determine a torque specification; monitoring, via a second speed sensor, a wheel speed of the at least one wheel of the motor vehicle to calculate the wheel slip of the at least one wheel of the motor vehicle; and regulating or controlling the speed of the drive motor based on the determined torque specification and the calculated wheel slip as a function of the minimum speed of the drive motor, such that the speed of the drive motor is always greater than the minimum speed and the maximum slip point is not exceeded, wherein the regulating or controlling switches between speed-based regulation or control to torque-based regulation or control after a current speed of the drive motor exceeds a specified multiple of the minimum speed of the drive motor. ### Claim 2 (depends on 1) The method of claim 1, further comprising: controlling or regulating the drive motor as a function of a preset target torque after the speed of the drive motor exceeds the minimum speed or another speed limit greater than the minimum speed. ### Claim 3 (depends on 2) The method of claim 2, further comprising: determining a minimum wheel speed dependent on the driving situation information for the at least one wheel of the motor vehicle; and determining the minimum speed of the drive motor as a function of the minimum wheel speed. ### Claim 4 (depends on 1) The method of claim 1, further comprising: determining a minimum wheel speed dependent on the driving situation information for the at least one wheel of the motor vehicle; and determining the minimum speed of the drive as a function of the minimum wheel speed. ### Claim 5 (depends on 4) The method of claim 4, further comprising: determining a respective minimum wheel speed is determined for several wheels of the motor vehicle as either a function of a largest wheel speed minimum or for a wheel with a largest current slip. ### Claim 6 (depends on 5) The method of claim 5, further comprising: determining the minimum wheel speed such that the slip of the wheel or the respective wheel at the speed of the motor vehicle is less than the slip at which maximum traction is achieved between the wheel and the ground. ### Claim 7 (depends on 4) The method of claim 4, further comprising: determining the minimum wheel speed such that the slip of the wheel or the respective wheel at the speed of the motor vehicle is less than the slip at which maximum traction is achieved between the wheel and the ground.