Design of high-efficiency dual-input converter with internal charge circuit

Abstract

This study develops a high-efficiency dual-input converter with an internal charge circuit. The proposed coupled-inductor-based converter can boost the voltages of two input power sources with different low-voltage levels to a controllable high-voltage dc bus. The high voltage dc bus can be taken as the main power for a high-voltage dc load or the front terminal of a dc-ac inverter. The charge circuit inside the proposed dual-input converter can provide the redundant energy from the major source for the auxiliary power source (e.g., battery module) to save the manufacturing cost. The techniques of voltage clamping and soft switching are employed in this converter, and the corresponding device specifications are adequately performed. Thus, the goal of high-efficiency dual-input power conversion with high voltage gain can be achieved. Some experimental results via a 1.5 kW-level prototype are given to verify the effectiveness of the proposed dual-input converter in practical applications.