An Isolated Single-Switch ZCS Resonant Converter with High Step-Up Ratio

This article proposes an isolated high step-up resonant converter which is suitable for low power application. The proposed converter is simple in structure since it employs only one switch while not necessitating a clamp circuit. Also, the proposed converter is able to achieve ZCS turn-on and turn-off of the switch and ZCS turn-off of diodes using a parallel resonant circuit, resulting in high efficiency. Furthermore, the proposed converter has reduced transformer volume due to zero dc-offset current in transformer. Experimental results on 450-W prototype are provided to validate the proposed concept.