A Voltage Stress Shared Bidirectional DC‐DC Converter With High Voltage Conversion Ratio and Wide Zero‐Voltage Switching Range

Abstract

ABSTRACT In this paper, we propose a voltage stress shared bidirectional DC‐DC converter designed for energy storage systems. Compared with traditional bidirectional DC‐DC converters, it features a high voltage conversion ratio, low voltage stress, low current ripple, and a wide soft‐switching range. The bidirectional DC‐DC converter achieves a high voltage conversion ratio and low voltage stress by splitting the low‐voltage side capacitors in series and incorporating a hybrid clamp structure on the high‐voltage side. Meanwhile, thanks to the split‐capacitor structure and reasonable switch configuration, all switching devices except S 2 experience a maximum voltage stress of only 100 V, significantly lower than other similar converters, reducing device costs and improving reliability. Additionally, the low‐voltage side employs a multiphase interleaved technique, significantly reducing the current ripple. All switches in the bidirectional DC‐DC converter can achieve zero‐voltage switching across the entire range by setting appropriate parameters. Meanwhile, this paper provides a detailed explanation of the working principles and steady‐state analysis of the bidirectional DC‐DC converter. By comparing the proposed converter in this paper with some of the advanced converters in recent years across various dimensions, it has been demonstrated that the performance advantages of this converter are evident. A 1000 W‐rated experimental prototype is presented, which can achieve a high efficiency at rated power. For different power applications, the converter can be designed according to the actual power requirements to obtain the optimal efficiency. The experimental results demonstrate the bidirectional DC‐DC converter's significant advantages, such as high voltage gain and low voltage stress, effectively verifying the feasibility of this topology.