Study on the Diagnosis for Degradation of Surge Arresters by Temperature Detection

Abstract

Surge arresters that protect the equipment of the electric power systems against lightning or switching overvoltage may degrade due to the stress of overvoltages and increase leakage currents under normal system voltages. As a preventative maintenance, the increase in the leakage current of surge arresters is normally checked, but this method takes time. As the leakage current increase causes the temperature rise of the surge arresters, the diagnosis with the thermographic camera is available. But this method is not common because there are few studies on the relationship between the temperature rise and the degradation level.

The authors measured the temperature rise of a polymer arrester under normal and aged conditions with a thermographic camera, and compared measured values to simulation results. The simulation showed good agreement with the measurements. The diagnosis by the temperature detection is proposed as one of the useful ways to find the degradation of surge arresters under operation in electric power systems.