Method and system for producing an active short circuit condition in an electric motor of a hybrid electric vehicle

A system for producing an active short circuit condition in an electric motor of a hybrid electric vehicle including a traction battery, the system comprising:

• an inverter comprising a plurality of switches, wherein the inverter is configured to be provided in electrical communication with the electric motor and the traction battery;
• and
• an inverter controller configured to be provided in electrical communication with the inverter and to generate driver signals to operate the plurality of switches of the inverter to produce three-phase alternating current for the electric motor to drive a vehicle propulsion system or to produce direct current for charging the traction battery;
• wherein the inverter controller is configured to compare a monitored speed of the electric motor to a speed threshold, and in response to the monitored speed exceeding the threshold, generate driver signals to operate the plurality of switches to produce an active short circuit condition in the electric motor to prevent overcharging of the traction battery;
• wherein the inverter controller comprises a processor and an electric circuit each configured to independently generate an active short circuit control signal operative to effectuate generation of the driver signals for producing the active short circuit condition, and wherein and the active short circuit condition is produced based on an active short circuit control signal generated by the electric circuit in an absence of an active short circuit control signal generated by the processor.

A non-transitory computer readable storage medium having stored computer executable instructions for producing an active short circuit condition in an electric motor of a hybrid electric vehicle including a traction battery, an inverter having a plurality of switches in electrical communication with the electric motor and the traction battery, and an inverter controller in electrical communication with the inverter and configured to generate driver signals to operate the plurality of switches of the inverter to produce three-phase alternating current for the electric motor to drive a vehicle propulsion system or to produce direct current for charging the traction battery, wherein execution of the instructions causes the inverter controller to:

• compare a monitored speed of the electric motor to a speed threshold;
• and
• generate, in response to the monitored speed exceeding the threshold, driver signals to operate the plurality of switches to produce an active short circuit condition in the electric motor to prevent overcharging of the traction battery, wherein the inverter controller comprises a processor and an electric circuit each configured to independently generate an active short circuit control signal operative to effectuate generation of the driver signals for producing the active short circuit condition, and wherein execution of the instructions causes the active short circuit condition to be produced based on an active short circuit control signal generated by the electric circuit in an absence of an active short circuit control signal generated by the processor.