A single-switch high step-up converter without coupled inductor

On the basis of summarizing the advantages and disadvantages of present high step-up converters, a novel single-switch high step-up converter without coupled inductor is proposed for the renewable energy sources in this paper. The proposed converter is based on the traditional SEPIC converter, not only can inherit the SEPIC's advantages that the continuous input current will constrain conducted EMI problems, but also can achieve high voltage gain without extreme duty cycle and the maximum voltage of semiconductor components is lower than the output voltage. Furthermore, the proposed converter has only one switch with low voltage stress and reduces the complexity of control strategy. The operating principle and parameter design of the proposed converter are analyzed in detail. Finally, a prototype has been built to verify its performance.