A new topology of direct AC to AC converter with soft-switching based on a MERS pulse link concept

This paper proposes a direct ac/ac converter without large smoothing capacitor. The first stage of the converter is a rectifier which generates a high frequency pulse voltage from an ac source. The second stage is a inverter which generates an ac voltage from the pulse voltage. The proposed converter does not have smoothing capacitor between the rectifier and inverter but has a drastically reduced capacitor size which is used for resonance in short switching cycle. Another advantage of the proposed converter is soft-switching operation of both the rectifier and inverter side. However, strict control of power flow is needed since there is no energy buffer between the rectifier and inverter. Thus, this paper also describes a basic control principle of the proposed converter and experimental results with a small scale setup.