INSULATION PERFORMANCE OF THICKLY COATED CONDUCTOR JOINT AND SUPPORT MODELS FOR GAS/SOLID HYBRID INSULATION SYSTEM WITH SF_6 SUBSTITUTE

摘要

SF_6 has been identified as a greenhouse gas with a high global warming potential. Therefore, in the long term, it may be important to examine the switchover to next-generation apparatuses using an alternative insulation gas. In the selection of an alternative gas, high-pressure natural gases, such as air, N_2, and CO_2, are promising environmentally friendly candidates. However, some strategies for enhancing insulation performance are necessary for their practical applications to apparatuses. In this study, we investigated the possibility of fabricating a gas-insulated apparatus using a gas/solid hybrid insulation system. Because the hybrid insulation system has a structure whose high-electric-field part is insulated using a solid insulator, there is a possibility that the same degree of compactness as that of the present apparatus can be achieved. However, there are important issues to be resolved before practical applications can be achieved, such as a study on methods of jointing and supporting a thickly coated conductor. In this paper, we describe the proposition of actual models jointing and supporting a thickly coated conductor, and evaluate the insulation performance of these models. The obtained results verified that these joint and support models are applicable to the gas/solid hybrid insulation system.