A High-Gain Three-Port DC-DC Converter With Soft-Switching for Renewable Energy System Applications

Three-port dc-dc converters (TPCs) integrate renewable energy systems, energy storage systems, and loads, which have the characteristics of high integration and high reliability. This article proposes a high-gain TPC with soft-switching for renewable energy system applications. In various operating modes of the proposed converter, all switches can achieve zero voltage switching turn-ON and all diodes can achieve zero current switching turn-OFF, which can effectively improve the efficiency of the converter. In addition, the coupled inductor achieves zero dc bias, which can reduce the magnetic size and core loss. The working principle, performance analysis, efficiency analysis, parameter design, energy management and control and of the proposed converter are presented. A 300-W experimental prototype with a 45-V photovoltaic voltage, a 90-V battery voltage, and a 380-V load voltage is built to verify the feasibility and correctness of the converter.