US 12,470,161 B2
Method for operating an electric machine, device for operating an electric machine, and electric drive system
Phillip Wagner, Ludwigsburg (DE); Gunther Goetting, Stuttgart (DE); and Michele Hirsch, Esslingen (DE)
Assigned to Robert Bosch GmbH, Stuttgart (DE)
Appl. No. 18/254,926
Filed by Robert Bosch GmbH, Stuttgart (DE)
PCT Filed Oct. 14, 2021, PCT No. PCT/EP2021/078434
§ 371(c)(1), (2) Date May 30, 2023,
PCT Pub. No. WO2022/117253, PCT Pub. Date Jun. 9, 2022.
Claims priority of application No. 10 2020 215 125.3 (DE), filed on Dec. 1, 2020.
Prior Publication US 2024/0030847 A1, Jan. 25, 2024
Int. Cl. B60L 3/00 (2019.01); H02P 21/00 (2016.01); H02P 21/08 (2016.01)
CPC H02P 21/08 (2013.01) [H02P 21/0017 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A method for operating an electric machine comprising a rotatably mounted rotor and a motor winding, wherein the motor winding is electrically connected to an electrical energy store (4) by means of a power electronics (3), the method comprising:
monitoring the machine (2) and/or an apparatus comprising the machine (2) for fault events, and
short circuiting the motor winding by triggering the power electronics (3) upon detection of a fault event, wherein a desired trajectory (T) for an actual current vector (iactual,dq) of an electric motor current flowing through the motor winding is ascertained, wherein the desired trajectory (T) extends from a current actual working point (AP1) of the machine (2) to a short-circuit working point (AP2) of the machine (2), wherein a pilot control action is predicted according to the desired trajectory (T), and wherein the power electronics (3) are triggered to short-circuit the motor winding according to the pilot control action in such a way that when the motor winding is short-circuited, a curve (V) of the actual current vector (iactual,dq) at least substantially matches the desired trajectory (T).
 
14. A device for operating an electric machine, wherein the machine (2) comprises a rotatably mounted rotor and a motor winding, and wherein the motor winding is electrically connected to an electrical energy store (4) by means of a power electronics (3), wherein a control unit (10) is configured to
monitor the machine (2) and/or an apparatus comprising the machine (2) for fault events, and
short circuit the motor winding by triggering the power electronics (3) upon detection of a fault event, wherein a desired trajectory (T) for an actual current vector (iactual,dq) of an electric motor current flowing through the motor winding is ascertained, wherein the desired trajectory (T) extends from a current actual working point (AP1) of the machine (2) to a short-circuit working point (AP2) of the machine (2), wherein a pilot control action is predicted according to the desired trajectory (T), and wherein the power electronics (3) are triggered to short-circuit the motor winding according to the pilot control action in such a way that when the motor winding is short-circuited, a curve (V) of the actual current vector (iactual,dq) at least substantially matches the desired trajectory (T).