Patent attributes
Systems and methods of detecting a failure of a permanent magnet synchronous motor system. A current of each phase coil of the motor is monitored. A value indicative of the power of the motor is compared to a threshold value indicative of power during a low power detection period. If the value indicative of the power fails to exceed the threshold value indicative of power for the entire low-power detection period, the system indicates a first error condition. The method also monitors the speed of the motor and indicates a second error condition if the speed of the motor remains below a speed threshold for an entire speed failure detection period. A third error condition is indicated if the current of at least one phase of the motor remains below a phase current threshold for an entire loss of phase detection period.
