A Modulation Strategy to Reduce Common-Mode Voltage for Current-Controlled Matrix Converters

In this paper, a basic hysteresis control strategy for current-controlled matrix converter (MC) is introduced and discussed. Based on the rectifier-inverter equivalent circuit, a novel primary modulation strategy for improving the input current quality of MC is presented. That is, space vector modulation is used for control input current, and hysteresis current strategy with zero vectors is used for control output current. Furthermore, an optimal modulation strategy that reduces common-mode voltage at the output is proposed. This optimal strategy maintains subdivision of 6 input current sectors and proper selection of zero vectors and switching sequences. Therefore, by using this optimal strategy, peak value of common-mode voltage is reduced by 33.3% and RMS value is reduced by over 50% compared to the unoptimizable modulation strategy. Finally, simulation and experimental results are provided to verify the validity and feasibility of modulation strategy proposed in this paper