Online Monitoring the Arc Contacts Erosion of HVCBs Based on Radiation Signals

Arc contacts are the key components that affect the lifespan of high-voltage circuit breakers (HVCBs). During the operation process, the arc contacts are continuously eroded and suffer mass loss. The direct impact of arc contacts degradation is the delay of the contact point. However, the present online monitoring methods cannot directly observe the condition of arc contacts. This study proposed three methods for online monitoring the contact point of HVCBs. By monitoring arc-excited radiation signals and analyzing their correlation with HVCB operations, we reveal that the contact and separation of arc contacts can be distinguished by radiation signals and support contact point measurement. Tests conducted on four different breakers show that the average measurement error is less than 1 mm and the average error percentage is less than 6%. The combined application of the proposed method further improves the monitoring performance. Proposed solution is applicable to all types of HVCBs, not invading into the circuit breaker (CB), not requiring multiple premeasurements or establishing a dataset, and applicable for online monitoring, which has good application potential.