Switch Open-circuit Fault Diagnosis and Fault-Tolerant Control Strategy for DC-DC Converters

This paper presents a simple and fast switch open circuit fault (OCF) diagnosis and fault-tolerant control strategy for non-isolated DC-DC converters. The fault diagnosis strategy, based on the change in the inductor current, uses a simple digital counter logic circuits for fault diagnosis and fault-tolerant control. The proposed method is tested on buck, boost and buck-boost topologies of the DC-DC converter. However, the method can be extended for other topologies of non-isolated dc-dc converter. The converters along with the proposed fault diagnosis and the reconfiguration strategy are modeled and simulated using the MATLAB Simulink environment. The robustness of the method against abrupt variations in the load as well as in the source voltage is examined. The results confirm that the proposed fault diagnosis and the reconfiguration strategy for the converter is effective in terms of simplicity, fast fault detection with accuracy and good voltage regulation.