経年OFケーブル接続箱の油浸絶縁紙異常様相の評価と解体ランクの区分方法の提案

カテゴリ: 論文誌(論文単位)

グループ名: 【B】電力・エネルギー部門

発行日: 2020/10/01

タイトル(英語): Evaluation of Abnormal Conditions of Oil-impregnated Insulation Papers in Aged Oil-filled Cable Joints and Terminations Removed After Service and Proposal of Classification Method for Ranking of their Abnormal Conditions

著者名: 栗原　隆史（（一財）電力中央研究所），牧野　裕太（（一財）電力中央研究所），髙橋　俊裕（（一財）電力中央研究所），髙橋　紹大（（一財）電力中央研究所）

著者名(英語): Takashi Kurihara (Central Research Institute of Electric Power Industry), Yuta Makino (Central Research Institute of Electric Power Industry), Toshihiro Takahashi (Central Research Institute of Electric Power Industry), Tsuguhiro Takahashi (Central Research Institute of Electric Power Industry)

キーワード: OFケーブル，ケーブル接続箱，撤去品調査，絶縁劣化，部分放電　oil-filled cables，cable joints and terminations，investigation of removed samples，insulation degradation，partial discharge

要約(英語): Degradation rate of electrical insulation performance of oil-filled (OF) cables has been considered small since void-less conditions are realized due to their oil-impregnated insulation systems under insulation oil pressure that exceeds atmospheric pressure. However, recently, insulation breakdowns have occurred in OF cable joints at extra-high voltage, and they were not predicted by dissolved gas analysis (DGA) of insulation oil. Therefore, it is necessary to improve the prediction accuracy of DGA for detection of partial discharges (PDs), which are known as a pre-breakdown phenomenon. Recently, it has been reported that traces of black color in oil-impregnated insulation papers are sometimes compounds of oxide sludge or copper sulfide, which were all regarded as carbonization due to PDs. Moreover, it has been reported that PD inception fields decrease with an increase in the rate of the total thickness of insulation papers with discoloration to the insulation thickness. To improve the prediction accuracy of DGA, such new findings should be taken into account when ranking abnormal conditions of insulation systems of cable joints and terminations, which gives the basic data for the prediction by DGA. In this study, abnormal conditions of oil-impregnated insulation papers were redefined and classified into trace of occurrences of PDs and two types of discoloration, and those of 264 aged OF cable joints and terminations removed after service were investigated. In addition, the above-mentioned rate was quantitatively evaluated for cable insulation systems, and locations of the abnormal conditions were investigated in detail for reinforced insulation systems. Taking these results into account, a new classification method for the ranking of abnormal conditions of oil-impregnated insulation systems was proposed.

本誌: 電気学会論文誌B（電力・エネルギー部門誌） Vol.140 No.10 （2020）

本誌掲載ページ: 769-779 p

原稿種別: 論文／日本語

電子版へのリンク: https://www.jstage.jst.go.jp/article/ieejpes/140/10/140_769/_article/-char/ja/