A Consideration on Neutral-Point Potential Balancing of 3-Level PWM Rectifier Applying Space Vector Modulation of Matrix Converter

This paper proposes voltage balance control for 3-level PWM rectifier using a space vector modulation of a matrix converter. When space vector modulation of matrix converter is applied to 3-level PWM rectifier, it can keep balanced DC-link voltage of 3-level PWM rectifier. However, when the DC-link voltage unbalance occurs, SVM of matrix converter cannot balance the DC-link voltage. In this paper, phase angle of input current reference is generated by PI controller in order to keep the phase angle of DC-link voltage to pi/6 rad. The proposed control can adapt not only voltage unbalance, but also a load unbalance. The validity of the proposed control is demonstrated by the simulation results.