Reconfigurable Nonisolated DC-DC Converter With Fault-Tolerant Capability

Malfunction of power semiconductor switches is the dominant cause of failure in power electronic converters. This article proposes a novel dual-switch dc-dc topology for high-reliability applications. The proposed converter is fault tolerant and supports operation under both step-down and step-up modes. The proposed topology can be reconfigured automatically under various switch-fault conditions in order to maintain normal operation. This is enabled by an affine-parametrization-based control design, which minimizes the transient impact of the faults. The reliability performance of the proposed converter is evaluated theoretically using a Markov model, demonstrating its superiority over conventional topologies. Finally, a laboratory prototype is developed and tested to verify the proposed design and control performance under switch faults.