Device for monitoring the harmonics rate in the supply of a synchronous electric machine with permanent magnet excitation

摘要

The monitoring circuit (60) generates synchronizing pulses reflecting the electrical frequency (fn) of rotation of a rotor (10b) relative to rotor. The band-stop notch filters receive signals representative of current in the windings (101-103) of a stator (10a), each representing center frequency that is servo-controlled to electrical frequency, to reject harmonic corresponding to electrical frequency. The harmonics that remain in signals output by filters, is measured and greatest measured value is compared with alarm threshold, continuously. Independent claims are included for the following: (1) unit for controlling synchronous electrical machine; and (2) driver device for driving rotary assembly mounted on active magnetic bearings.