Structure of three-phase to two-phase indirect Matrix converter and a switching method for nine-switch Matrix converter

AC-AC statistic Matrix converter is one of the most widely-used, and also very first, power electronics systems. These converters are conventionally designed and produced with a middle DC circuit. Because of the volume size and the short lifetime of electrolyte capacitors used in the middle DC circuits, their reliability level decreases. The direct AC-AC converter does not have such shortcomings. As the bidirectional switches are not well developed, and besides because of commutation problems, direct AC-AC converter is unsuitable replacements for the AC-DC-AC converters. Although the proposed converter in this paper belongs to direct AC-AC converter family, it does not suffer commutation problems. To produce two phase voltage, Scott transformers are mostly used for industrial purposes, however their cost and core loss is much higher than the matrix converters. In this paper, a two-phase indirect matrix converter is introduced, in which the number of switches is reduced as much as possible in order to decrease the switching losses. Simulation results, presented in section 3, show that the proposed circuit and its control system have a good performance.