Patent ID: 8669733

Claim:
A power supply circuit for an electric motor, the circuit comprising a plurality of inverter bridge arms, each having means for connection to a respective winding of the motor, wherein each inverter bridge arm comprises in series a first insulated gate bipolar transistor and a junction field effect transistor that are connected to a controller, and wherein the circuit includes a second insulated gate bipolar transistor connected in series with each field effect transistor and connected to the controller, and a damping resistor connected in parallel with the second bipolar transistor, the controller is arranged to put the power supply circuit in an active mode and a passive mode so that: in the active mode, the first insulated gate bipolar transistor and the first junction field effect transistor are controlled to power the windings of the motor in succession, while the second first insulated gate bipolar transistor is kept closed by the controller in order to short circuit the damping resistor; in the passive mode, all of said insulated gate bipolar transistors are naturally open in the absence of any power supply, with the first junction field effect transistor naturally remaining closed in the absence of any power supply in order to connect the windings of the motor to the damping resistor.