A Family of Single-Switch High Step-Up DC-DC Converters Based on Switched-Capacitor Converters

In this paper, a family of single-switch high step-up DC-DC converters based on switched-capacitor (SC) cells and coupled inductor (CL) or built-in transformer (BIT) is proposed. By replacing one active switch in the 3X-ladder switched-capacitor converter (SCC) with the primary side of a CL or BIT whose secondary side is incorporated into a multiplexed current path, the proposed topology integrates the high power-density feature of a ladder SCC with the voltage-lift effect of a CL or BIT. In addition, the problems of high current spikes and limited efficiency in the voltage regulation range of the traditional ladder SCC are tackled, making them suitable for distributed generation systems, microgrids, and so forth. For illustration purposes, the performance of the topologies within the family is compared in multiple ways, detailed operation principles and design considerations of one specific converter are given. Finally, experimental results are presented to verify the analytical findings.