Efficiency Characterization and Optimization of Isolated Bidirectional DC-DC Converter Based on Dual-Phase-Shift Control for DC Distribution Application

Compared to the traditional single-phase-shift control, dual-phase-shift (DPS) control can greatly improve the performance of the isolated bidirectional dc-dc converter (IBDC). This paper gives a detailed switching characteristic analysis of IBDC under DPS control, establishes a power loss model to predict the dissipated power for each power component, and analyzes the efficiency-optimized characteristic across the whole range. On this basis, an efficiency-optimized switching strategy is proposed and the corresponding control scheme is designed and implemented. At last, an experimental prototype was implemented to verify the feasibility of the proposed switching strategy and correctness of the theoretical analysis. The experimental results show that the proposed method can minimize the power loss and maximize the system efficiency, and these performances are particularly effective for operation conditions with high voltage conversion ratio.