# US 2016/0355167 A1 · Method for operating an electric motor for braking a vehicle, and control device for an electric motor designed at least for braking a vehicle > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2016/0355167 A1 - Document ID: US20160355167A1 - Status: Published application - Kind: A1 - Application number: 15/165,575 - Filed: 2016-05-26 - Published: 2016-12-08 - Earliest claimed: 2015-06-02 - Assignees: Robert Bosch GmbH - Applicants: Robert Bosch GmbH - Inventors: Andreas Erban; Jochen Feinauer; Bastian Richter; Michael Knoop - Web page: https://patentgrep.com/patent/US20160355167A1 ## CPC - B60T 8/17616: {Microprocessor-based systems} - B60L 7/26: Controlling the braking effect - B60L 15/2009: {for braking} - B60T 1/10: by utilising wheel movement for accumulating energy, e.g. driving air compressors - B60T 13/586: {the retarders being of the electric type} - B60T 13/748: {acting on electro-magnetic brakes (combined with fluid-pressure brake systems B60T13/667)} - B60L 2240/12: Speed - B60L 2240/423: Torque - B60L 2240/465: Slip - B60T 2270/602: ABS features related thereto - Y02T 10/64: Electric machine technologies in electromobility - Y02T 10/72: Electric energy management in electromobility - B60T: VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL (electrodynamic brake systems for vehicle, in general B60L; brakes per se, i.e. devices where braking effect occurs, including ultimate brake actuators, F16D); ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES - B60L: PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES (arrangements or mounting of electrical propulsion units or of plural diverse prime-movers for mutual or common propulsion in vehicles B60K1/00, B60K6/20; arrangements or mounting of electrical gearing in vehicles B60K17/12, B60K17/14; preventing wheel slip by reducing power in rail vehicles B61C15/08; dynamo-electric machines H02K; control or regulation of electric motors H02P); SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES (electric coupling devices combined with mechanical couplings of vehicles B60D1/64; electric heating for vehicles B60H1/00); ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL (control or regulation of electric motors H02P); MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A method for operating an electric motor for braking a vehicle, including controlling the electric motor in such a way that the vehicle is slowed or decelerated with the aid of a motor braking torque exerted by the controlled electric motor. The method includes ascertaining whether a requested setpoint speed change is in a predefined normal range, and if so, the electric motor is controlled in such a way that a load to be applied by the electric motor remains less than or equal to a nominal load capacity of the electric motor. If the requested setpoint speed change is outside the predefined normal range, the electric motor is controlled in such a way that the load to be applied by the electric motor exceeds the nominal load capacity of the electric motor, at least during a predefined overload operation time interval. ## Claims ### Claim 1 A method for operating an electric motor for braking a vehicle, comprising: controlling the electric motor in such a way that the vehicle is slowed or decelerated at least with the aid of a motor braking torque exerted by the controlled electric motor on at least one of: i) at least one wheel, and ii) at least one axle of the vehicle, the electric motor being controlled with regard to a setpoint speed change requested by one of a driver of the vehicle or an autonomous automatic control system of the vehicle, taking at least one default signal into account; ascertaining whether the requested setpoint speed change is in a predefined normal range, taking the at least one default signal into account; if the requested setpoint speed change is in the predefined normal range, controlling the electric motor in such a way that a load to be applied by the electric motor remains less than or equal to a nominal load capacity of the electric motor; and if the requested setpoint speed change is outside the predefined normal range, controlling the electric motor in such a way that a load to be applied by the electric motor exceeds the nominal load capacity of the electric motor, at least during a predefined overload operation time interval. ### Claim 2 (depends on 1) The method as recited in claim 1, wherein if the requested setpoint speed change is outside the predefined normal range, the electric motor is controlled in such a way that the load to be applied by the electric motor exceeds the nominal load capacity of the electric motor during the predefined overload operation time interval of 750 ms maximum. ### Claim 3 (depends on 1) The method as recited in claim 1, wherein, if the requested setpoint speed change is outside the predefined normal range, at least one estimated or ascertained variable concerning a friction braking torque instantaneously exerted by at least one wheel brake cylinder of a hydraulic braking system of the vehicle is also taken into account during the control of the electric motor. ### Claim 4 (depends on 1) The method as recited in claim 1, wherein if the requested setpoint speed change is outside the predefined normal range, the load to be applied by the electric motor is controlled above the nominal load capacity of the electric motor only until at least one of: i) the estimated or ascertained variable exceeds a predefined or set limiting value, and ii) a wheel slip is detected. ### Claim 5 (depends on 4) The method as recited in claim 4, wherein the limiting value is set taking into account at least one of: i) an instantaneous speed of the vehicle, ii) an instantaneous longitudinal acceleration of the vehicle, and iii) an instantaneous transverse acceleration of the vehicle. ### Claim 6 A control device for an electric motor which is designed at least for braking a vehicle, the control device comprising: an electronics unit which is designed for controlling the electric motor, taking into account at least one provided default signal concerning a setpoint speed change requested by a driver of the vehicle or an autonomous automatic control system of the vehicle, in such a way that a motor braking torque is exertable on at least one of: i) at least one wheel of the vehicle, and ii) at least one axle of the vehicle, with the aid of the controlled electric motor, so that the vehicle may be slowed/decelerated at least with the aid of the motor braking torque of the electric motor; wherein the electronics unit is additionally designed to: i) recognize whether the requested setpoint speed change is in a predefined normal range, taking the at least one default signal into account, ii) control the electric motor in such a way that a load to be applied by the electric motor remains less than or equal to a nominal load capacity of the electric motor, if the requested setpoint speed change is in the predefined normal range, and iii) control the electric motor in such a way that the load to be applied by the electric motor exceeds the nominal load capacity of the electric motor, at least during a predefined overload operation time interval, if the requested setpoint speed change is outside the predefined normal range. ### Claim 7 (depends on 6) The control device as recited in claim 6, wherein the electronics unit is additionally designed for controlling the electric motor in such a way that the load to be applied by the electric motor exceeds the nominal load capacity of the electric motor during the predefined overload operation time interval of 750 ms maximum, if the requested setpoint speed change is outside the predefined normal range. ### Claim 8 (depends on 7) The control device as recited in claim 7, wherein the electronics unit is designed for also taking into account at least one provided or self-determined variable concerning a friction braking torque instantaneously exerted by at least one wheel brake cylinder of a hydraulic braking system of the vehicle, during control of the electric motor, at least if the requested setpoint speed change is outside the predefined normal range. ### Claim 9 (depends on 8) The control device as recited in claim 8, wherein the electronics unit is additionally designed for controlling the electric motor in such a way that the load to be applied by the electric motor is above the nominal load capacity of the electric motor only until at least one of: i) the provided or self-determined variable exceeds a predefined or set limiting value, and ii) a wheel slip signal regarding a wheel slip that is instantaneously present is received by the electronics unit, if the requested setpoint speed change is outside the predefined normal range. ### Claim 10 (depends on 9) The control device as recited in claim 9, wherein the electronics unit is additionally designed for setting the limiting value, taking into account at least one of: i) an instantaneous speed of the vehicle, ii) an instantaneous longitudinal acceleration of the vehicle, and iii) an instantaneous transverse acceleration of the vehicle. ### Claim 11 An electric motor which is designed at least for braking a vehicle, the electric motor including a control device comprising: an electronics unit which is designed for controlling the electric motor, taking into account at least one provided default signal concerning a setpoint speed change requested by a driver of the vehicle or an autonomous automatic control system of the vehicle, in such a way that a motor braking torque is exertable on at least one of: i) at least one wheel of the vehicle, and ii) at least one axle of the vehicle, with the aid of the controlled electric motor, so that the vehicle may be slowed/decelerated at least with the aid of the motor braking torque of the electric motor; wherein the electronics unit is additionally designed to: i) recognize whether the requested setpoint speed change is in a predefined normal range, taking the at least one default signal into account, ii) control the electric motor in such a way that a load to be applied by the electric motor remains less than or equal to a nominal load capacity of the electric motor, if the requested setpoint speed change is in the predefined normal range, and iii) control the electric motor in such a way that the load to be applied by the electric motor exceeds the nominal load capacity of the electric motor, at least during a predefined overload operation time interval, if the requested setpoint speed change is outside the predefined normal range. ### Claim 12 A braking system for a vehicle, the braking system including a control device, the control device comprising: an electronics unit which is designed for controlling the electric motor, taking into account at least one provided default signal concerning a setpoint speed change requested by a driver of the vehicle or an autonomous automatic control system of the vehicle, in such a way that a motor braking torque is exertable on at least one of: i) at least one wheel of the vehicle, and ii) at least one axle of the vehicle, with the aid of the controlled electric motor, so that the vehicle may be slowed/decelerated at least with the aid of the motor braking torque of the electric motor; wherein the electronics unit is additionally designed to: i) recognize whether the requested setpoint speed change is in a predefined normal range, taking the at least one default signal into account, ii) control the electric motor in such a way that a load to be applied by the electric motor remains less than or equal to a nominal load capacity of the electric motor, if the requested setpoint speed change is in the predefined normal range, and iii) control the electric motor in such a way that the load to be applied by the electric motor exceeds the nominal load capacity of the electric motor, at least during a predefined overload operation time interval, if the requested setpoint speed change is outside the predefined normal range.