Zero-Crossing Distortion and Neutral- Point Voltage Imbalance Analysis of VIENNA Rectifier with Carrier-Based Discontinuous PWM Control

Three-phase VIENNA rectifier with carrier-based pulse-width modulation (CBPWM) is widely used in various fields for its simple structure and high reliability. However, continuous high switching frequency of very semiconductors leads to considerable switching losses. The carrier-based discontinuous modulation (CB-DPWM) method is a preferable method to avoid the switching losses and achieve high efficiency. However, it results in extra issues around the zero-crossing area, causing current distortion. Therefore, a compensation strategy is deployed to address this problem. Moreover, a retrofit zero sequence component injection method is proposed to enhance the neutral-point potential balance ability of the CB-DPWM method. The feasibility of the employed methods are verified by simulation.