Research On The Test Method Of ZnO Surge Arresters

Nowadays, ZnO Surge Arresters (MOA) are more and more popularly applied in power system due to its excellent contribution as key equipment on limiting power system over-voltage.Firstly, the dissertation introduced the structure and operational principle of ZnO surge arresters, analyzed composition and characteristic of leakage currents of ZnO surge arresters for shunt grading capacitor, expounded routine test, judging methods and testing objective that regulated by DL/T596-1996"Preventive Test Code For Electric Power Equipment".Secondly, the dissertation particularized a accident for ZnO surge arresters, concluded that routine test and judging method cannot make final verdict on the quality of ZnO surge arresters for shunt grading capacitor.Finally, the dissertations discussed the solutions for the abovementioned problems. Concluded that it may be improved by singular fetched out the bottom of shunt capacitors and modifying the structure of ZnO surge arresters, Judging methods also included"Preventive test code for electric power equipment"regulated standards and manufacturer's standards; on the other hand, As for the energized ZnO surge arresters, applied triple harmonic wave current and basic wave current and combined with internal pressure supervision may effectively concluded the condition of MOA of the shunt grading capacitors. Under the normal pressure, it can be judged that whether shunt capacitor worsened upon basic wave current increased, and judging ZnO resistance flake worsened upon obtained the triple harmonic wave current increased, and judging the internal of ZnO was intruded by moisture upon the internal pressure of ZnO reduced.