Method and arrangement for controlling the output of electric consumers connected to an AC line voltage

摘要

The method varies the firing angle about a given set point for the desired power, not only towards larger but also smaller values. The firing angle determines the amount of phase control with full waves following one after another. The variation of the firing angle results in the slow increase of even numbered harmonics and a strong reduction of odd numbered harmonics. Lack of symmetry of the firing angle in time is generated between two full waves following directly one after the other.