Monitoring intermediate circuit voltages in rectifiers involves comparing digitized signal harmonic and reference voltage values, outputting indication signal representing their difference

摘要

The method involves digitizing the intermediate circuit voltage at the output of a capacitor circuit, frequency-dependent filtering of its harmonics, determining the harmonic voltage value , comparing with a reference voltage value and outputting an indication signal representing the difference between the harmonic and reference voltage values. AN Independent claim is also included for the following: an arrangement for operating an electric motor.