METHOD FOR OPERATING ASYNCHRONOUS MOTORS AND CORRESPONDING DEVICE

摘要

Asynchronous motors are controlled by way of two- or three-phase controllers that include at least two pair of thyristors connected in antiparallel and fired at certain intervals. According to the inventive method, a fundamental wave with the desired frequency is defined for the first phase and in the other phase a respective fundamental wave is defined that has the same frequency as that in the first phase, but phase-shifted by corresponding values. For every phase, firing intervals are marked that have the same polarity as the respective fundamental wave. Those intervals of the potential firing intervals are used for every phase at which there is a potential firing interval in one of the two other phases. These intervals are used as the actual firing intervals.