Potential distribution analysis and improvement of 1000 kV gas insulted switch metal oxide arrester

This paper presents the study on the potential distribution of the 1000 kV gas insulated switch (GIS) metal oxide arrester (MOA). Based on the idea of field-circuit combination, the 3D finite element method (FEM) and circuit analytic method are applied to analyze and improve the potential distribution of the 1000 kV MOA. The methods of adjusting the grading rings, increasing the voltage level of the ZnO discs and adding parallel capacitors are analyzed to improve the potential distribution of the GIS MOA. Regulations of the three methods are studied and optimal schemes of the GIS MOA are achieved to improve the potential distribution coefficient to be within +15%.