Accelerated aging test to determine the replacement criterion of distribution surge arresters

This paper provides the results of accelerated aging test of 18 kV ZnO surge arresters to investigate the leakage current characteristics. It was impossible to establish the replacement criterion for field operating surge arresters because conventional aging test was only focused on the aging of ZnO elements. In general it is possible to replace the aged arresters before the failure in the field using the leakage current measurement because it must be increased by the aging. But we cannot use this method because we don´t know the characteristics of the surge arresters installed in the field. Therefore in this paper we applied operating voltage and accelerating cycle which consists of temperature and humidity to the arresters. Then we measured the variation of total and resistive leakage current and found out the characteristics of the aged surge arresters