Performance Evaluation of Circuit Breaker Electrical Contact Based on Dynamic Resistance Signature and Using Health Index

High-voltage circuit breakers (CBs) are extremely important components for the function of power supply system. The need to predict proper function of CB has increased over the years. Dynamic resistance measurement (DRM) is an effective method to evaluate the condition of CB’s contact. This paper aims to predict the correlation between the various levels of contact degradation and characteristics of dynamic resistance waveform. Five diagnosis parameters are extracted from DRM curve. Using scoring and weighting techniques, heath index is applied to clearly identify the condition of CB as healthy, need caution, and risky. The proposed method is implemented with ten healthy and ten faulty electrical contacts as examples for illustrating the effectiveness of the method in assessing the CB condition.