Stepless Current Commutation in a Three Phase to Three Phase Matrix Converter

Matrix converter (MC) is a generalized AC to AC power converter which connects the source and the load by an array of switches without any intermediate energy storage element. The magnitude and frequency of the output voltage as well as the input displacement factor can be controlled. Thus, matrix converter offers an almost all silicon solution for AC to AC power conversion. One major difficulty of matrix converter is the complicated commutation procedure of the bidirectional switches in absence of freewheeling path. The commutation therefore requires finite steps and sensing of either voltage or current polarity. The stepless current commutation strategy for two phase to two phase MC has the distinct advantages of the absence of voltage and/or current sensors and minimum possible commutation time. This paper further analyses the stepless current commutation strategy for its application in a three phase to three phase MC.