Two-Winding Coupled-Inductor-Based DC–DC Converter with Two Synchronous Power Switches and Ultra-High Voltage-Gain Capability

This article describes a non-isolated boost DC–DC configuration that uses a two-winding coupled inductor (CI) together with two synchronous power switches to acquire ultra-high voltage conversion at relatively low duty cycles. The proposed structure combines a quadratic gain stage with the coupled inductor to realize a substantial output voltage boost. The overall conversion ratio can be flexibly adjusted through two independent design factors: the duty cycle of the switches and the turns ratio of the coupled inductor providing additional degrees of freedom for optimization. The main merits of the converter are its very high voltage gain (VG), reduced voltage stress (VS) on the active switches, continuous input current, common ground between input and output, soft-switching operation for diodes D3 and D4, and the possibility of using a synchronized gate-drive scheme. The paper thoroughly examines the operating intervals, steady-state behavior, design procedure, and efficiency performance, and also develops a dynamic model for control-oriented analysis. To highlight its strengths, the proposed topology is systematically compared with several existing high-gain converters. Finally, experimental outcomes obtained from a 400-W laboratory prototype operating at 50 kHz confirm the feasibility and effectiveness of the proposed converter in achieving high voltage gain, reduced device voltage stress, and high efficiency under practical operating conditions.