MODELING AND SIMULATION OF HVDC EPOXY SPACER FOR SF6 GAS INSULATED SYSTEM

Abstract

High voltage insulation design skill is one of the key technologies for HVDC equipment to acquire its reliable performance. As DC electric field configuration is totally different from that of AC and its distribution is affected by the electrical conductivity of insulating materials. And DC electric field analysis should be determined considering voltage profile and temperature difference affecting the electrical conductivity. In this respect, DC insulation design of HVDC epoxy spacer in SF6 gas should be carried out considering DC electric field distribution with different temperature conditions. In this work, DC electric field analysis of epoxy spacer in SF6 was performed considering various epoxy materials with different nano fillers including Al2O3 and SiO2. Electrical conductivity of these epoxy specimen were measured and DC electric field analysis was carried out to find the most appreciable epoxy type in HVDC SF6 gas insulated system (GIS). From the simulation results, Al2O3 with 2 per hundred resin (phr) epoxy showed the best electric field characteristics. By use of Al2O3 with 2 phr epoxy, DC electric field simulation works were done considering polarity reversal and thermal analysis to find the optimum configuration of epoxy spacer. Consequently, it was possible to find the suitable contact angle of epoxy spacer and the configuration of epoxy spacer to reduce electric field intensity during polarity reversal.