A soft-switching boost DC to AC converter without smoothing capacitor using a MERS pulse link concept

One of challenges in power conversion with conventional topologies is a large smoothing capacitor. This paper proposes a soft-switching boost DC to AC converter, which is a combination of a DC/AC converter and a pulse voltage generator working as a step-up chopper. The pulse generator generates high frequency pulse voltage from a low DC voltage with relatively small inductor and capacitor. The DC/AC converter generates three phase ac voltage from the pulse voltage. The proposed converter does not have smoothing capacitor between the chopper and the DC/AC converter 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 chopper and DC/AC converter side. This paper also describes a basic control principle of the proposed converter and experimental results with a small scale setup.