Research on the influence of different defects upon GIS disconnector electric field distribution

GIS disconnector contains various special components, such as moving electrode, insulated pull rod, basin-type insulator, which are sensitive to the electric field. Due to the mechanical movement, which is realized when the conversion between open and closed states of circuit, it´s possible to produce some metal, nonmetal particles, or mechanical damage on components, etc. This paper mainly focuses on the impacts of foreign materials with diverse factors which can affect the electric field distribution in GIS disconnector. First, with a common 550kV GIS disconnector structure and its operating condition parameters, the typical distribution of potential and electric field have been calculated. Then, based on further calculation, comparisons and analysis of defects have been done, including surface defects and foreign material with different size, properties, and locations. Influence on electric field by internal defects in the insulated pull rod, was also concerned. At last, the correlation between defects and the electric field distribution have been systematically analyzed. The research achievements will provide references and guidance for structural design, manufacturing, and field assembly of GIS disconnector, to help improve the safety and long-term stability of the equipment.