Control strategy for a hybrid five-level three-phase PWM rectifier using twelve switching devices

This paper proposes a new circuit topology for a multilevel PWM rectifier. The proposed circuit combines a diode clamp type topology with a flying capacitor type topology. As a result, the proposed circuit uses only 12 switches, despite the use of a five-level three-phase PWM rectifier. Further, the proposed circuit can obtain good performance as same as to a conventional multilevel circuit. This paper describes the features of the proposed topology; the control strategy and loss analysis using circuit simulation. In addition, the basic operation of the proposed method is confirmed by simulation and experimental results. The proposed converter achieved 3.4% THD for the input current and 97.4% efficiency for a 1 kW class experimental setup.