Output Power Control for Isolated Secondary-Resonant AC-DC Modular Matrix Converter Using Pulse Amplitude Modulation

Abstract

This paper presents the output power control for a unidirectional isolated secondary-resonant AC-DC (SR-AC-DC) converter using the Pulse Amplitude Modulation (PAM) of the high-frequency voltage. The proposed SR-AC-DC converter consists of the primary modular matrix converter (MMxC), the high-frequency transformer, and the secondary diode-rectifier-circuit with the resonant capacitors. The proposed AC-DC converter directly converts a medium-voltage power source to a DC voltage using the MMxC. Therefore, the proposed AC-DC converter can achieve a high-efficient and downsized converter for high-power applications. In the proposed control method, the output power of the proposed circuit can be controlled by changing the amplitude of the primary voltage. The proposed control method is simple output power control using only one parameter such as the amplitude of the primary voltage. The stable transient characteristics is obtained. The effectiveness of the proposed control method is verified by the experiments using the 200 V-6 kW laboratory prototypes.