Study on relationship between behavior of the bubble in pearl-chain type electrical treeing and the bubble generated in dielectric liquid at starting electric discharge

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K04105
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 21010:Power engineering-related
• Research Institution: Ehime University
• Principal Investigator: IHORI HARUO 愛媛大学, 理工学研究科(工学系), 教授 (70249861)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 電気トリー / シリコーンゴム / 部分放電 / パールチェーン型トリー

Outline of Final Research Achievements

The voltage superimposing a sine wave on a rectangular wave was applied to the sample electrode system, in order to examine the polarity dependence of the initial bubble which is a stage before the propagation of an electrical tree. When the negative monopolar voltage was applied, a bubble occurred from the tip of the needle electrode, and two protrusions occurred. The one protrusion greatly progressed at the application of the reversed positive voltage. It was considered that the pressure in the bubble suddenly changed by the polarity inversion and the bubble grew bigger with some protrusions on the surface.

Free Research Field

絶縁材料

Academic Significance and Societal Importance of the Research Achievements

電気トリーの進展過程は、電力ケーブルやポリマーがいしなど、電力機器全般にわたって、絶縁設計に変革をもたらす絶縁技術のさらなる発展が期待できる。また、ゲル中であることに着目すれば、近年のパワーモジュールの封止材としての高電界特性を明らかにしているとも言え、その分野の産業界にも有用な知見となる。さらには、これらの結果を踏まて、より絶縁耐力を向上させた新たな材料の開発につなげていくことが期待される。