Power factor correction (PFC) is widely used in many industry fields. In this paper, a novel multiplexed and paralleled PFC rectifier (MPPR) is proposed. Compared with the paralleled traditional six-switch buck-type PFC rectifier (SSBPR), the proposed one uses fewer switches by multiplexing. And it is beneficial for system hardware design. The commutation states of the rectifier are illustrated in detail. By comparing the active power switches, it is shown that the efficiency of the rectifier is similar to that of the traditional paralleled one. Because the commutation states for the upper and lower parts of the rectifier are different, the controller of the converter is analyzed step by step. The forward duties and the inductor current references are discussed by considering the different input voltages of the upper and lower parts of the MPPR. Then the controller is presented and analyzed. Finally the effectiveness of the MPPR is verified by experiments.

This paper proposes a high-efficiency PFC rectifier based on multiplexing the switches. Compared with a traditional six-switch PFC rectifier, the proposed rectifier extends the switches’ active angle by making use of three bridge rectifiers. As a result, lower conduction resistance can be realized for switches. Consequently, system efficiency can be improved. Compared with a traditional six-switch PFC rectifier with doubled switches, the proposed rectifier can achieve almost the same efficiency improvement while no additional switches are needed. Since continuous inductor current is chopped and resulting current pulses cannot be injected into the grid directly, input filter design and resonance damping are discussed for the proposed rectifier. The controller design of the rectifier is analyzed. The inductor current reference is shaped considering the input voltage envelope and forward duties. Finally, the effectiveness of the proposed rectifier is verified through simulations and experiments.

To realize a high-power density capacitive coupler for miniaturized rotary application, a parameter design method is proposed in this article. Since a capacitive coupler is composed of metal plates and external capacitors, limitations include two parts. One is air breakdown voltage limitation of metal plates, and the other one is withstanding voltage limitation of external capacitors. To quantify voltage limitation, voltage stress is analyzed. Then, an optimal design method for external capacitors is proposed, realizing minimum voltage stress and optimal load condition, simultaneously. Using an optimal external capacitor, a parameter design method is proposed to maximize power density. In which, the air breakdown voltage limitation determines the range of resonant frequency. Then, the withstanding voltage limitation determines specific resonant frequency and composition of external capacitors. Experimental results show the proposed method can realize DC-DC efficiency of 91.35% and power density of 423 W/in³ under a 1 kW output condition.