A three-level rectifier with reduced number of power switches based on one-cycle control

This paper presents a three-level rectifier with reduced number of power switches based on one-cycle control. Only six power switches with voltage rating of half DC-link are adopted in this multilevel rectifier. A nonlinear control method, one-cycle control, is used to control the rectifier. The controller is composed of some integrators with reset, flip-flops, comparators and linear components, which has the characteristics of simple, high precision. In addition, it works under constant switching frequency which is desirable for industrial applications. A neutral-point potential balancing method for the three-level rectifier based on one-cycle control is developed in this paper. Based on the proposed control strategy, the line currents are balanced and sinusoidal, and the neutral-point potential achieves balance. Simulation results are provided to verify the effectiveness of the proposed control strategy.