Fault Tolerant Isolated Dual Active DC-DC Converter Using WBG Devices

In this paper, a bidirectional isolated DC-DC converter is proposed for MVDC applications. In this topology, an active 5-level T-type converter is used in primary and secondary sides of a high frequency transformer. The proposed converter features better fault tolerance, higher efficiency, and reduced output voltage ripple compared to common dual active bridge DC-DC converters. Phase disposition pulse width modulation and dual-phase shift control methods are applied to control the proposed converter. A fault tolerant algorithm is proposed for this converter. The operation of the proposed structure is verified by simulations carried in PLECS. Finally, a 600 W prototype of the proposed structure was built and tested.