A Study on Simplification of Commutation Methods for Three-Phase Direct Matrix Converters

This paper presents a simplified one-step commutation method for Direct Matrix Converter (DMC). A comprehensive study on commutation strategies of three-phase to three-phase DMC in a three-wire system is conducted, starting from the most commonly employed four-step commutation strategy. By considering the input voltages and the direction of the output currents, the commutation method can be simplified into three-step or two-step commutation methods. The input voltages are divided into six sectors. Through the constant holding of two switches within each sector, the proposed simplified one-step commutation method is achieved, which significantly contributes to the reduction of control complexity. The principle of the proposed strategy is explained in detail. Simulation results are used to verify effectiveness and performance of this proposed strategy.