Fault-Tolerant Regenerative Sensorless Braking of PMAC MotorsEnables Degraded Mode of Operation for Functional Safety

Inhalt:
A method is described that immediately decelerates a running machine applying electromagnetic torque to fulfill the safety function Safe Stop (SS1). It relieves the motor integrated mechanical holding brake and thus reduces wear and tear. In this way, fault-tolerant sensorless parameter-independent emergency stopping of permanent magnet alternating current (PMAC) motors is achieved. The controlling algorithm in the safety-related logic overrides failures of the power electronic devices and of the position feedback system. It decides on particular lines of action with respect to the detected type of fault.