Adaptive harmonic blocking compensator

Properties of a compensator with adaptive balancing and harmonic blocking features for correcting the power factor of the load, balancing an unbalanced load, and reducing the waveform distortion caused by harmonic generating loads are presented in the paper. It combines a harmonic blocking compensator and a thyristor-controlled susceptance circuit which makes adaptive compensation possible. Therefore, it is referred to as an "adaptive harmonic blocking compesnsator". A harmonic blocking compensator is built of a eries harmonic filter tuned to the fundamental frequency and a shunt capacitor. A suitable thyristor-controlled susceptance circuit, which contains a thyristor-switched inductor, needs to provide a variable susceptance without injecting an excessive amount of harmonic current. This paper presents the fundamentals, operation, and design of such a compensator. This research is supported with results from experiments with a laboratory prototype.