High efficient design of reconfigurable step-up DC-DC converter with fault-tolerant capability

Power electronic converters often malfunction because semiconductor power switches are prone to failure. This paper proposes a DC-DC converter that is capable of safe operation under switch failures. The proposed fault-tolerant (FT) technique is based on a reconfiguration strategy without requiring additional devices. Also, the power flow is considered in the configuration design, resulting in a reduced amount of additional power to be processed, thus producing a more efficient converter structure. In addition, the voltage stress across the active elements is low and always equals half of the output voltage. During switch-fault modes, the presented control system minimizes the transient impact of the faults to preserve the normal operation of the converter. After various switch faults, the new configuration of the proposed converter supports operation with new characteristics. Additionally, a fuse-MOSFET pair is embedded to protect the FT DC-DC converter from the excessive current that might damage circuit elements. The proposed converter in the continuous current mode (CCM) is evaluated, and its characteristics are discussed in detail. The proposed converter has been implemented, and the necessary evaluations have been conducted to verify the theoretical study and feasibility of the control system.