研究者詳細 - 小島　寛樹

講演・口頭発表等 - 小島　寛樹

分割表示 795 件中 641 - 660 件目／全件表示 >>

高温超電導限流変圧器（HTc-SFCLT）用YBCO並列導体の限流特性

大村弘輝，伊藤智志，小島寛樹，早川直樹，遠藤奎将，大久保仁

平成20年電気学会全国大会

電力システムの総合経済性を考慮した変圧器の最適保守方法

金光正樹，塩見僚，小島寛樹，早川直樹，遠藤奎将，大久保仁

平成20年電気学会全国大会

SF₆ガス中における金属異物の部分放電電流パルスおよび電磁波特性に関する検討

西澤佳奈子，大楠崇司，小島寛樹，早川直樹，遠藤奎将，吉田昌展，内田克己，大久保仁

平成20年電気学会全国大会

SF₆ガス中リーダ放電進展に及ぼす解離生成物の影響

吉田聡，細井勇佑，小島寛樹，早川直樹，遠藤奎将，大久保仁

平成20年電気学会全国大会

Novel Measurement and Analysis System for Investigation of Partial Discharge Mechanism in SF₆ Gas 国際会議

H. Kojima, N. Hayakawa, F. Endo, H. Okubo

12th International Middle-East Power System Conference 2008年3月13日 South Valley University

開催年月日： 2008年3月

記述言語：英語会議種別：口頭発表（一般）

開催地：Aswan 国名：エジプト・アラブ共和国

An understanding of mechanism of partial discharge (PD) in SF6 gas is critical for diagnosis of PD in electric power equipment and contributes to the optimization of the design of electric power applications. However, for complexity of PD characteristics under non-uniform electric field, the mechanism of PD in SF6 is not comprehended enough. For this reason, we aim to reveal the PD mechanism by measuring current waveform, propagation characteristics and light emission of PD in SF6 gas and analyzing these data. For this purpose, we have developed excellent measurement and analysis techniques. For an analysis of PD under ac voltage application, not only PD waveforms but also PD propagation property is essential. We have constructed partial discharge current pulse waveform analysis (PD-CPWA) system. This system has enabled us to observe PD current sequentially at high speed and analyze the propagation of PD current pulse statistically. By the application of PD-CPWA system to diagnosis of PD activity due to the metallic particle in SF6, we could identify the particle type and size. On the other hand, for an analysis of PD under impulse voltage application, an ultra high-speed PD measurement by various methods is extremely important. In order to investigate the impulse PD mechanism spatially and temporally, the simultaneous measurement of current and light emission intensity waveforms, streak and still light emission images and temporal evolution of spectrum of PD light emission have been carried out. By using this synchronous ultra-high speed PD measurement system, we revealed the change of light emission from decomposition products depending on the step propagation of leader discharge. © 2008 IEEE.

DOI： 10.1109/MEPCON.2008.4562383

Scopus

その他リンク： https://www.webofscience.com/wos/woscc/full-record/WOS:000259262500089

Comparison of Partial Discharge Characteristics for Different Defect Types in SF₆ Gas Insulation System 国際会議

D. A. Mansour, T. Okusu, K. Nishizawa, H. Kojima, N. Hayakawa, F. Endo, H. Okubo

12th International Middle-East Power System Conference 2008年3月13日 South Valley University

開催年月日： 2008年3月

記述言語：英語会議種別：口頭発表（一般）

開催地：Aswan 国名：エジプト・アラブ共和国

The high reliability, less maintenance and compact size of Gas Insulated Switchgears (GISs) have made them the primary choice for many utilities. However, sometimes insulation defects inside GIS can be a serious threat to safe operation of GIS and can lead to costly disruption of supply. As insulation failure usually starts with partial discharge (PD) activity, this paper investigates the differences in PD characteristics in SF6 gas among different types of defects. The defect types considered in this study are particles in a gas gap, particles adhered on a spacer surface and spacer/electrode detachment. Different experiments were made for sequential PD measurements using the system of PD-Current Pulse Waveform Analysis (PD-CPWA). The PD phase characteristics, PD pulse number and PD current were analyzed for the different defect types. Also the ratio of voltage increment to phase increment at the next PD pulse appearance (Δu/ΔΦ pattern) was obtained and compared for each defect type. Experimental results show that correct identification of defects can be achieved based on considered PD characteristics. © 2008 IEEE.

DOI： 10.1109/MEPCON.2008.4562335

Scopus

その他リンク： https://www.webofscience.com/wos/woscc/full-record/WOS:000259262500041

機器信頼性に基づく電力システムの保守・運用の最適化

金光正樹，塩見僚，小島寛樹，早川直樹，遠藤奎将，大久保仁

電気学会誘電・絶縁材料/電線・ケーブル合同研究会 2008年2月19日電気学会誘電・絶縁材料/電線・ケーブル技術委員会