Study on a New Method of Metal Oxide Surge Arrester Monitoring

Metal oxide surge arresters (MOA) is a power system overvoltage protection device, and the online monitoring of the MOA is an important means to ensure the safe operation of the power system. This paper presents a new MOA insulation defects monitoring method. This method is based on the relative change in capacitance to MOA insulation defects as characteristic parameter, the aging classified as a kind of local defects, the system disturbance contains higher harmonic of transient voltage and current as the signal source, dynamically generated MOA partial insulation discriminant function of the defects in the diagnosis. The maximum value of the discriminant function corresponds to the local insulation defects. The proposed method contributes to the MOA monitoring methods and the development of technology.