Common-Mode Voltage Reduction in Matrix Converter by Zero Vector Elimination

Matrix Converter (MC) is a direct energy conversion device with high input power factor. In the Direct Matrix Converter modulation, the Space Vector Modulation (SVM) method by simultaneous control of the input current and output voltage is used. In this method sum of the phase voltages in the central point of load is nonzero, then nonzero Common-Mode Voltage (CMV) in central point is produced. Due to CMV, the leakage current at connection point between the motor and natural point is produced, then the motor bearing current is increased and effective lift time of motor is reduced. In this paper, CMV reduction methods are studied, and then a new CMV reduction method is proposed, in which the CMV is reduced to 57% of dc link voltage. In this method, an active vector is used instead of the zero vector. Simulation results are presented to verify effectiveness of the proposed approach.