Single-phase AC-AC converters using power MOSFETs

The authors analyze the performance of a single-phase AC-AC converter with particular emphasis on the output harmonic content and input voltage utilization. A complete power circuit that makes use of power MOSFETs is given. An analysis of the output waveform shows that its harmonic content is very low. It is also found that the ratio of the switching frequency to the modulating triangular wave, has negligible effect on the harmonic content. Hence, the ratio can be chosen at nominal value of 4 and it is mainly used to control the amplitude of the fundamental component in the output. The only disadvantage of the single-phase AC-AC converter is that the amplitudes of certain harmonic frequencies become abnormally high