An Isolated Bidirectional DC/DC Converter with Wide Output Voltage Range

In DC power supply systems, there is often a significant voltage difference between the supply and load sides, which can lead to poor compatibility of the power system. To address this issue, this paper proposes a new isolated bidirectional DC/DC converter. It integrates a four-switch Buck-Boost with a LLC converter with partial switch reuse, effectively enhancing overall performance. A hybrid control strategy that combines PWM and frequency modulation is designed, enabling a wide soft-switching range under varying output conditions. The paper provides a detailed analysis of the converter's operating modes. Additionally, a simulation model and an experimental prototype are designed to validate the theoretical results. The final results confirm that the converter can maintain soft-switching characteristics over a wide output voltage range.