Vacuum breakdown concerning influence of contamination distribution of the electrode surface

Research Project

Project/Area Number	17K06293
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Research Field	Power engineering/Power conversion/Electric machinery
Research Institution	Saitama University
Principal Investigator	Yamano Yasushi 埼玉大学, 情報メディア基盤センター, 准教授 (30323380)
Project Period (FY)	2017-04-01 – 2020-03-31
Project Status	Completed (Fiscal Year 2019)
Budget Amount *help	¥4,680,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥1,080,000) Fiscal Year 2019: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000) Fiscal Year 2018: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000) Fiscal Year 2017: ¥2,600,000 (Direct Cost: ¥2,000,000、Indirect Cost: ¥600,000)
Keywords	真空 / 絶縁破壊 / 汚損分布 / 真空ギャップ / 表面汚損 / 放電 / 汚損 / 真空絶縁破壊 / 表面分析
Outline of Final Research Achievements	Vacuum breakdown characteristics under uniform and non-uniform electric field condition were investigated. Sample electrodes have different surface conditions which are contaminated by a cutting oil. These electrode surfaces are analyzed by the XPS (X-ray Photoelectron Spectroscopy). To investigate an influence of the contamination distribution on the electrode surface on the breakdown characteristics in vacuum, we conducted repetition breakdown tests in vacuum and X-ray photoelectron spectroscopy to analyze the chemical state of the electrode surface. From the experimental results, it is suggested that the contamination around the outside of the electrode surface deteriorates the breakdown voltage at the final stage of conditioning process. We obtained the influence of the surface contaminated condition on the vacuum breakdown characteristics for the uniform and non-uniform electrode gap.
Academic Significance and Societal Importance of the Research Achievements	真空は高耐電圧特性を含む様々な特徴を有することから，分析機器や加速器などで利用されている．機器の電圧や電界の増強により真空中での絶縁破壊現象が障害となっている。したがって，真空中の絶縁破壊機構の解明および絶縁耐力の向上に関する研究は不可欠である。機器の絶縁設計においては、電極表面の状態、特に清浄度合いの管理が重要であり、電極表面の清浄・汚損の度合いに対する真空ギャップの絶縁特性のデータが必須となり、本研究はこれらの基礎的なデータとなり得る。