An Improved Space Vector Modulation Strategy for Suppressing Common-Mode Voltage of Quasi-Z Source Indirect Four-bridges Matrix Converter

An improved space vector modulation strategy for suppressing common-mode voltage of the system is proposed for an indirect four-bridges matrix converter topology consisting of a quasi-Z source matrix rectifier and a conventional voltage-source four-bridges inverter. Two valid vectors of equal amplitude and opposite direction near the reference voltage vector are selected for zero vector substitution in the inverter stage. The space vector modulation region is divided into 12 sectors in the rectifier stage, and the appropriate zero vector is selected. The simulation results in MATLAB / Simulink show that the modulation strategy not only improves the voltage transfer ratio, but also overcomes the negative effects of load imbalance and reduces common-mode voltage effectively.