Model-based fault analysis of a high-voltage circuit breaker operating mechanism

In this paper, a dynamic model is developed for high-voltage circuit breakers to extract fault features and causes. Lagrange’s method is applied using geometric equations of mechanism components to write the model. Unlike previous approaches, the proposed method reveals and analyzes all types of circuit breaker operating mechanism faults. Early fault detection, which is a vital requirement of the fault diagnosis system, becomes feasible by keeping track of changes in the contact travel curve in the proposed model. Resulting faults in the travel curve are analyzed mathematically in order to find out the exact origin of the fault. Field test results show the accuracy and reliability of the fault detection method.