Fault Identification for Circuit Breakers Based on Vibration Measurements

Mechanical condition assessment of circuit breakers (CBs) in the power system, if correctly applied, can make an optimal decision on whether, where, and how to perform maintenance. This article presents a new approach to the detection and identification of CB's mechanical states, using its vibration data during switching operations. The morphological correlation coefficient (MCC), which can detect whether or not a fault is present in a CB, is introduced first. Then, a quantitative methodology to specify the specific fault type of the CB, i.e., the ensemble empirical mode decomposition (EEMD)-Hilbert marginal spectrum energy entropy (HMSEE), combined with a classifier [e.g., support vector machine (SVM)], is proposed. By using this approach, the mechanical condition of CBs can be reliably estimated. Some typical mechanical faults of a 12-kV vacuum CB were simulated in the test laboratory to evaluate the effectiveness of the proposed approach. The application in two field cases demonstrates the applicability of the proposed approach.