摘要
The insulation performance of SF_(6)insulated high voltage direct current apparatus are often analysed in a pure electric field or electro-thermal coupled field while the fluid behaviour of SF_(6)gas flow is often ignored.However,frequent flashover along the support insulators inside the SF_(6)insulated wall bushing indicates that the fluid characteristics of SF_(6)may have considerable influence on the interior insulation performance of the bushing.This paper has simulated the thermo-fluid coupled field in the SF_(6)insulated wall bushing based on the finite element method model.The result shows that buoyant flow of SF_(6)has evident influence on the temperature distribution in the bushing.On this basis,the effect of the thermo-fluid field on the electric field distribution along the insulator as well as on the motion behaviour of the metallic particles is analysed.Furthermore,the effect of different thermal boundary conditions on analysis of the multiphysics field in the bushing is discussed and the most suitable one for simulation and experiment is suggested.Comparisons are made between different supporting structures and modification advices are proposed.This paper can serve as a good reference for subsequent research studies on SF_(6)insulated apparatus in which the temperature gradient or the motion of the micro-sized metallic particles shall be considered.
基金
Fundamental Research Funds for the Central Universities,Grant/Award Number:2020MS005
Science and Technology Project of China Huaneng Group Co.,Ltd.,Grant/Award Number:HNKJ20-H02
Independent Research Project of State Key Laboratory of Alternate Electrical Power System with Renewable Energy Source(North China Electric Power University),Grant/Award Number:LAPS2020-03。
