Electronic stop detection for synchronous motors involves using change in switch-on duration and/or phase positions as criterion for detecting stop and switching off synchronous motor

摘要

The method involves measuring the phase positions (A,B) and/or switch-on periods of the voltages over both phases of the synchronous motor (4) and using a change in the switch-on duration and/or phase positions as a decision criterion for detecting the stop and hence switching off the synchronous motor. The measured values are compared with stored values or values determined in previous periods. AN Independent claim is also included for an arrangement for implementing the method.