Patent ID: 11878604
Assignee: VOLVO CAR CORPORATION
Field: Transport (Mechanical engineering)
Classification: CPC B  H  Y | IPC B  H

Claim 5:
6. A propulsion system for an electric vehicle, the propulsion system comprising:
a high voltage battery unit having a first high voltage battery connected in series with a second high voltage battery such that a nominal operating voltage of the high voltage battery unit is the sum of a voltage of the first high voltage battery and a voltage of the second high voltage battery;
a first three-phase power inverter connected to a first set of three phases of a six-phase electric machine and a second three-phase power inverter connected to a second set of three phases of the six-phase electric machine, wherein the first three-phase system is formed by the first three-phase power inverter and of the first set of three phases of the six-phase electric machine and the second three-phase system is formed by the second three-phase power inverter and the second set of three phases of the six-phase electric machine; and
a propulsion system control unit configured to:
detect a fault of the first or the second three-phase system and operate the first and second three-phase systems in a safe-state mode, wherein, if a back electromotive force, back-EMF, of the faulty three-phase system is higher than the operating voltage of the high voltage battery unit, the propulsion system control unit is configured to control the inverter of the faulty three-phase system to operate in an active short-circuit mode, where transistors of the inverter are kept in a closed state, switching of the transistors is stopped and current and voltage is circulating between the inverter and the electric machine of the faulty three-phase system in a closed short-circuited loop.