Topology and Modulation for a New Indirect Matrix Converter to Reduce the Common-Mode Voltage

Abstract

In this paper, a new indirect matrix converter (IMC) topology with two insulated gate bipolar transistors (IGBT) set in the upper and lower dc-link is proposed to suppress the common-mode voltage (CMV). Meanwhile, two new space vector modulation (SVM) strategies are redesigned to control this topology. The first strategy utilizes the equivalent zero voltage vectors to replace the zero voltage vectors for reducing the CMV, while the second strategy selects and utilizes specific active voltage vectors and equivalent zero voltage vectors to suppress the CMV based on the input current sector. Comparative simulation and experimental research for the two strategies are carried out for the new IMC topology, which validates that the CMV can be reduced to 57.7% or 37.1% of the one in the conventional IMC system. Besides, the proposed new IMC system is experimentally verified that it can keep a satisfied CMV suppression performance when feeding an induction motor. Moreover, the efficiency analysis also indicates that the new topology will not bring in obvious additional power loss under the proposed SVM strategies even though two IGBTs are added in the dc-link.