An interleaved parallel bidirectional DC/DC converter topology with the function of fault tolerance

摘要

The interleaved bidirectional DC-DC converter is a core component of the battery energy storage system. However, if an open-switch fault occurs at the interleaved bidirectional DC-DC converters, the currents of two branches will become unbalanced, which will increase the battery current ripple and shorten the life of batteries and energy storage systems. In this paper, a fault tolerant topology is proposed to improve the reliability of the interleaved parallel bidirectional DC/DC converter. Firstly, the normal operation of the battery energy storage system has been analysed. Then, the fault-tolerant topology is presented. Compared with the normal topology, the fault tolerant topology adds an additional branch of bidirectional switch. When an open-switch fault occurs, the faulty branch would be cut off, then, the fault-tolerant circuit will be put into operation quickly, and the converter can keep continuous operation with acceptable performance. Simulation results are presented to verify the feasibility and effectiveness of the proposed topology.