Insulation structure research and design optimization of ± 1100kV DC SF6 gas insulated through wall bushing

Abstract

The insulation structure research and design optimization of ±1100kV DC SF6 gas insulated through wall bushing is an important basis and technical key for the core technology research and device development of ± 1000kV DC SF6 gas insulated through wall bushing. It is also an important basis for the formation of bushing structure design and process technology, which is of great significance to improve the electrical performance of bushing. The ±1100kV DC SF6 gas insulated through wall bushing monomer bears the full voltage and current of the system, and the distribution of internal insulation electric field is complex. At the same time, it is affected by many factors such as electric field shielding, insulator surface charge accumulation, material non-linearity and so on. The improvement of voltage level puts forward higher requirements for bushing structure type, material performance and electric field uniformity regulation. Based on the actual engineering and scientific needs, this topic carries out the insulation structure research and design optimization of ±1100kV DC SF6 gas insulated through wall bushing. The design and selection of the bushing insulation structure, high current carrying structure and mechanical support structure based on multi physical field analysis. Through electrical, thermal and mechanical analysis, design and select reasonable structural type for casing under the action of multiple factors. Design optimization of typical insulation structure of bushing. The electric field simulation and intelligent algorithm are used to design the configuration parameters of shielding electrode and epoxy cast insulator, optimize the electric field intensity on the electrode surface, inhibit the charge accumulation on the insulator surface and improve the flash-over voltage of insulator.