報告書番号

H11001

タイトル（和文）

自然ガスを使用した次世代ガス絶縁機器の絶縁設計 －ガス／固体ハイブリッド絶縁方式における被覆導体接続・支持スペーサの試作と絶縁性能評価－

タイトル（英文）

Insulation Design of Gas-insulated Power Equipment using Natural Gas as SF6 Substitute -Insulation Performance of Coated Conductor Joint and Support Spacer for Gas/Solid Hybrid Insulation System

概要 （図表や脚注は「報告書全文」に掲載しております）

本研究では，CO2などの自然ガスと固体絶縁物による導体の被覆を併用したハイブリッドガス絶縁方式を提案しており，SF6ガスと比較して絶縁耐力の弱い自然ガスを使用する場合に，絶縁面からコンパクト化を図る有効な手段となることが期待できる。ハイブリッドガス絶縁方式の実適用に向けた評価では，厚膜の被覆導体の接続あるいは支持部が，絶縁上の弱点となる可能性があり，実適用に有効な被覆導体の接続・支持構造の検討が重要である。本論文では，電界解析に基づき，接続・支持部の電界集中が発生しない構造を考案した。これに基づき，接続・支持モデルを製作し，CO2ガスを対象に，絶縁破壊特性を取得し，今回考案した接続・支持構造の有効性を実証した。

概要 （英文）

SF6 has been identified as a greenhouse gas with a long atmospheric lifetime. Therefore, the reduction in the amount of SF6 released into the atmosphere has progressed. In the long term, it is preferable to reduce the amount of SF6 used. Therefore, regarding the replacement of gas-insulated apparatus, it may be important to examine the switchover to more environmentally friendly apparatus using an alternative insulation gas.
In the selection of an alternative gas, it is thought that high-pressure natural gases, such as air, nitrogen (N2), and carbon dioxide (CO2) are promising environmentally friendly candidates. However, some strategies for enhancing insulation performance are necessary for their practical applications to apparatus because the dielectric strengths of these gases are about 1/3 that of SF6. In this study, we investigated the possibility of gas-insulated apparatus using a hybrid gas insulation system which has the combined features of a solid insulator and a dielectric gas. Because the hybrid gas insulation system has a structure which the 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 in spite of the application of a natural gas. Therefore, it may be useful for one of the alternative equipment using the hybrid gas insulation system when a present compact gas-insulated apparatus is replaced. However, there are important problems to be resolved before practical application can be achieved, such as a study on methods of jointing and supporting the thick-coated conductor.
In this report, we describe the proposition of thick-coated conductor joint models based on electric field analysis and experimental results using the fundamental models, and the evaluation of insulation performance for these models for hybrid gas insulation system.

報告者

キーワード