A Measurement Technique of the 3rd Harmonic Leakage Current of ZnO Elements

초록

This paper presents the developed measurement method of resistive leakage current and the technique of deterioration diagnosis for ZnO element. The resistive leakage current increasing with time leads to a thermally unstable state that may even experience a disaster. We have developed the leakage current detection device and analysis program for ageing test and durability evaluation for ZnO element. The third harmonic components of the resistive leakage current may be used as an indicator to identify whether the ZnO arresters is in good state or in bad. The proposed monitoring systems for both the resistive leakage current and the third harmonic current might be useful to develop a method of prodicting the defect and performance deterioration of ZnO arresters in power system applications.