Envelope cycloconverter harmonic reduction using Comb filter

Traditionally, comb filter applications are often restricted to digital and communications industry, where the filtered signals are always at very high frequencies. No previous attempt had been made to use these types of filters for low frequency power applications. In this paper, an attempt is made to use comb filter for harmonics reduction of the envelope cycloconverter output voltage waveforms. Theoretical and practical investigations made in the present work, proving the practicability of using comb filter for selective elimination of harmonic components for the cycloconverter output waveforms. Total harmonic distortion is highly reduced and near sinusoidal output voltage and current waveforms were produced. The problem of harmonic phase unbalanced relationships associated with the 3-phase conventional envelope cycloconverter is also investigated and solved.