Methods, systems and apparatus for controlling a multi-phase inverter

An apparatus, comprising:

• a multi-phase inverter to drive a multi-phase electric machine;
• a fault detector to indicate detection of a sensor fault of a sensor that is used for sensing at least one of a rotor position and a rotor angular velocity of the multi-phase electric machine, wherein the sensor is designed to provide at least one of an angular velocity signal indicative of the angular velocity of a rotor of a multi-phase electric machine, and an angular position signal indicative of the angular position of the rotor of the multi-phase electric machine;
• and
• a controller operable, in response to receiving an indication from the fault detector that the sensor fault has been detected, to estimate angular velocity of a rotor of the multi-phase electric machine based on feedback stator currents, to determine whether the estimated angular velocity is greater than a transition angular velocity threshold, and to apply either:
• an open-circuit response at the multi-phase inverter when the estimated angular velocity of the multi-phase electric machine is less than the transition angular velocity threshold;
• or
• a short-circuit response at the multi-phase inverter when the estimated angular velocity is greater than the transition angular velocity threshold.

A non-transitory machine-readable medium comprising sets of instructions operable in a controller to cause the controller to perform operations in response to the controller receiving an indication that a sensor for sensing either a position or angular velocity of a rotor has faulted, the operations comprising:

• estimating, based on feedback stator currents, angular velocity of a rotor of a multi-phase electric machine;
• determining whether the estimated angular velocity is greater than a transition angular velocity threshold;
• and
• generating control signals to cause either:
• an open-circuit response to be applied at a multi-phase inverter when the estimated angular velocity of the multi-phase electric machine is less than the transition angular velocity threshold;
• or
• a short-circuit response to be applied at the multi-phase inverter when the estimated angular velocity is greater than the transition angular velocity threshold.