High-Efficiency Bidirectional CLCLC Resonant DC–DC Converter With Soft-Switching Performance and Stability Optimization

This study proposes an improved high-efficiency bidirectional CLCLC resonant DC-DC converter, highlighting its significance as a vital component in power electronic systems. The converter operates at a high switching frequency of 100 kHz while achieving zero-voltage switching (ZVS) and zero-current switching (ZCS), effectively minimizing switching losses. In a bidirectional DC-DC converter (BDDC), a distinct interleaved pulse-width modulation (PWM) control strategy is applied to both the low-voltage and high-voltage sides, enabling a zero-voltage-switched half-bridge (ZVSHB) topology for seamless bidirectional power flow. In this study, a detailed circuit configuration and bidirectional operation modes are discussed, followed by rigorous small-signal modeling (SSM) and state-space averaging (SSA) methods using MATLAB software to assess the dynamic closed-loop stability. Extensive PSIM simulations provide insight into the soft-switching performance, while a 1 kW experimental model was built to validate the theoretical and simulation outcomes. The converter reached maximum efficiencies of 96.332% when operating in boost mode and 96.623% in buck mode. Furthermore, the analytical efficiency and power loss breakdown are presented, demonstrating a close agreement between the theoretical predictions and the experimental results. A comprehensive comparative evaluation of existing isolated and non-isolated bidirectional converter topologies demonstrate that the proposed design achieves superior performance by delivering higher circuit efficiency and reduced structural complexity.