近年來，在電力設(shè)備絕緣技術(shù)領(lǐng)域中，局部放電檢測技術(shù)廣受關(guān)注。廣東省電力科學(xué)研究院高壓所一批專家學(xué)者多年來致力于該專業(yè)的研究與應(yīng)用，幾年來積累了不少經(jīng)驗(yàn)，為更好地推廣應(yīng)用技術(shù)，特編寫了本書。本書主要包括7 章內(nèi)容，分別是概述、局部放電理論、局部放電特高頻電磁波在GIS 中的傳播特性、局部放電特高頻檢測技術(shù)基礎(chǔ)、局部放電特高頻檢測的標(biāo)定、局部放電特高頻定位技術(shù)、特高頻檢測技術(shù)在GIS 局部放電狀態(tài)監(jiān)測中的應(yīng)用。
局部放電好比是電氣設(shè)備體內(nèi)的癌細(xì)胞，它伴隨著設(shè)備內(nèi)部絕緣材料或結(jié)構(gòu)的微觀缺陷而生。局部放電因其電、熱、機(jī)械和化學(xué)效應(yīng)會(huì)對(duì)絕緣材料造成侵蝕并加速材料的老化和劣化，就像癌細(xì)胞的擴(kuò)散，并將最終引發(fā)絕緣擊穿故障。電氣設(shè)備局部放電發(fā)生的原因多種多樣，如絕緣設(shè)計(jì)不合理，絕緣材料中存在雜質(zhì)、氣泡或裂紋，電極表面粗糙或因劃傷而引發(fā)的尖刺，設(shè)備裝配中的偏差，設(shè)備運(yùn)輸或試驗(yàn)過程中帶來的各類損傷，設(shè)備在運(yùn)行過程中因震動(dòng)而導(dǎo)致的連接部件的松動(dòng)，以及絕緣的老化等，這些因素均會(huì)導(dǎo)致設(shè)備內(nèi)部電場應(yīng)力集中而引發(fā)局部放電。局部放電本身并不等同于絕緣故障，一般可以在電氣設(shè)備運(yùn)行過程中存在相當(dāng)長的時(shí)間。局部放電的發(fā)生、發(fā)展及其破壞作用具有很大的隨機(jī)性，并因絕緣材料、絕緣結(jié)構(gòu)、運(yùn)行工況以及周圍環(huán)境等眾多因素的不同而不同，這也使得局部放電狀態(tài)及危害程度的評(píng)估十分復(fù)雜。國際上最早提出局部放電這一概念是20 世紀(jì)初，到20 世紀(jì)80 年代就已經(jīng)建立了國際公認(rèn)的測量標(biāo)準(zhǔn)（IEC 270）。長期以來局部放電現(xiàn)象一直受到人們的高度重視，局部放電測量被廣泛應(yīng)用于高壓設(shè)備的型式試驗(yàn)、出廠試驗(yàn)、交接試驗(yàn)以及絕緣預(yù)防性試驗(yàn)，成為檢驗(yàn)設(shè)備質(zhì)量工藝水平及絕緣性能的關(guān)鍵參數(shù)，同時(shí)也是反映高壓設(shè)備早期絕緣缺陷最靈敏和最有效的指標(biāo)。多年以來，人們也一直致力于將局部放電檢測應(yīng)用于設(shè)備的帶電測試，然而由于局部放電帶電檢測情況下的靈敏度、高壓設(shè)備工作現(xiàn)場復(fù)雜的電磁干擾等技術(shù)瓶頸的制約，局部放電帶電檢測和在線監(jiān)測技術(shù)的發(fā)展非常緩慢。自1986 年英國Strathclyde 大學(xué)在蘇格蘭的Torness 核電站安裝了第一套氣體絕緣金屬封閉開關(guān)設(shè)備（GIS）的局部放電特高頻監(jiān)測裝置以來，局部放電特高頻檢測技術(shù)日益成為該領(lǐng)域研究的熱點(diǎn)，發(fā)表的論文不下數(shù)百篇。特高頻法（ultra-high frequency，300MHz～3GHz）就是利用GIS 局部放電輻射出的特高頻電磁波信號(hào)進(jìn)行檢測的一種方法。研究表明，GIS 局部放電將會(huì)產(chǎn)生很陡的脈沖電流，并向四周輻射多種頻率的電磁波，通過特高頻傳感器接收其中300MHz～3GHz 的電磁波信號(hào)，可實(shí)現(xiàn)對(duì)局部放電的檢測和定位。由于特高頻法具有抗干擾能力強(qiáng)、靈敏度高等特點(diǎn)，而且這種非接觸式的測量方式對(duì)于二次設(shè)備和檢測人員而言都更安全，系統(tǒng)結(jié)構(gòu)簡單，特別適合于在線監(jiān)測，因而較之于其他檢測方法具有明顯的優(yōu)勢。局部放電特高頻在線檢測技術(shù)的應(yīng)用則隨著北京2008 奧運(yùn)會(huì)的舉辦而掀起了高潮，也正是自2008 年起，國家電網(wǎng)公司陸續(xù)發(fā)布了十余項(xiàng)規(guī)范輸變電設(shè)備狀態(tài)檢修的企業(yè)標(biāo)準(zhǔn)，廣東電網(wǎng)公司則于2009 年底首次啟動(dòng)了GIS 局部放電特高頻在線監(jiān)測系統(tǒng)的大規(guī)模招標(biāo)采購。在國家電網(wǎng)公司十二五規(guī)劃中，智能電網(wǎng)建設(shè)引領(lǐng)能源產(chǎn)業(yè)發(fā)展的引擎，智能設(shè)備及狀態(tài)評(píng)估均離不開在線檢測技術(shù)的支撐，局部放電特高頻檢測技術(shù)赫然在列。然而，在局部放電特高頻在線檢測技術(shù)迅速發(fā)展的過程中，也暴露出一系列的問題：（1）相關(guān)技術(shù)標(biāo)準(zhǔn)、規(guī)范不健全，缺乏統(tǒng)一有效的指導(dǎo)；（2）設(shè)備運(yùn)行現(xiàn)場復(fù)雜的放電類干擾依然嚴(yán)重影響特高頻檢測的應(yīng)用；（3）特高頻局部放電檢測技術(shù)在故障診斷和狀態(tài)評(píng)估的理論和應(yīng)用均不完善；（4）特高頻局部放電檢測技術(shù)本身應(yīng)用的瓶頸較高，難度較大。這些問題導(dǎo)致人們一度對(duì)局部放電特高頻檢測技術(shù)存在很大爭議，令現(xiàn)場從事運(yùn)檢工作的技術(shù)人員感到困惑。廣東電網(wǎng)公司電力科學(xué)研究院（簡稱廣東電科院）從20 世紀(jì)90 年代末期開始至今，一直持續(xù)進(jìn)行局部放電特高頻檢測技術(shù)研究和工程應(yīng)用，近年來開展了GIS 標(biāo)準(zhǔn)化相關(guān)的一系列關(guān)鍵技術(shù)研究，首次提出并建立了國內(nèi)外首個(gè)GIS 全尺寸標(biāo)定平臺(tái)、開發(fā)了現(xiàn)場靈敏度校核系統(tǒng)，技術(shù)成果全面應(yīng)用于廣東電網(wǎng)公司GIS 生命周期管理，極大地提高了GIS的運(yùn)行可靠性，2012 年實(shí)現(xiàn)GIS 事故率同比下降54%。本書基于廣東電科院近年來在GIS 局部放電特高頻檢測技術(shù)取得的應(yīng)用成果，參考國內(nèi)外相關(guān)著作和文獻(xiàn)編著而成，在此向相關(guān)著作和文獻(xiàn)的作者表示衷心的感謝。本書在編寫過程中得到了華北電力大學(xué)高壓教研室?guī)熒拇罅χС�，吸納了鄭書生、詹花茂、王彩雄、魏振等各位老師和博士的研究資料及成果，全書得到了李成榕教授的悉心指導(dǎo)。在此向華北電力大學(xué)各位老師和學(xué)生一并表示感謝！由于學(xué)識(shí)水平有限，成書倉促，不當(dāng)之處敬請諒解，并請不吝批評(píng)指正！編著者2016 年5 月
本書的編著者盧啟付、李興旺、李端嬌、唐志國等為廣東省電力科學(xué)研究院高壓所的專家，多年來一直致力于局部放電檢測技術(shù)的研究與應(yīng)用。
前言
1 概述··············································································································1
1.1國內(nèi)外狀態(tài)檢修背景簡介······································································1
1.2局部放電檢測技術(shù)··················································································4
1.3局部放電特高頻在線檢測技術(shù)······························································6
1.4局部放電特高頻檢測技術(shù)的主要內(nèi)容················································12
2局部放電理論·····························································································14
2.1局部放電的概念···················································································14
2.2局部放電的物理過程············································································15
2.3局部放電的基本參數(shù)············································································24
2.4局部放電輻射原理················································································26
2.5常規(guī)局部放電與特高頻局部放電信號(hào)之間的關(guān)系·····························30
3局部放電特高頻電磁波在GIS中的傳播特性·········································33
3.1波導(dǎo)理論·······························································································33
3.2 GIS中電磁波傳播規(guī)律仿真·································································34
3.3 GIS結(jié)構(gòu)對(duì)電磁波傳播的影響·····························································43
3.4 GIS中局部放電特高頻電磁波傳播特性的試驗(yàn)研究··························47
4局部放電特高頻檢測技術(shù)基礎(chǔ)··································································58
4.1天線接收原理·······················································································58
4.2局部放電特高頻檢測系統(tǒng)····································································59
4.3局部放電特高頻信號(hào)的時(shí)頻特征························································62
4.4局部放電特高頻檢測的抗干擾技術(shù)····················································64
4.5局部放電特高頻檢測的模式識(shí)別························································78
5局部放電特高頻檢測的標(biāo)定·····································································92
5.1時(shí)域參考法測量原理············································································93
5.2局部放電特高頻檢測性能的關(guān)鍵指標(biāo)·················································96
5.3基于GTEM小室的局部放電特高頻標(biāo)定方法····································99
5.4 GIS局部放電標(biāo)定結(jié)果的檢驗(yàn)···························································102
6局部放電特高頻定位技術(shù)·······································································105
6.1 GIS局部放電特高頻定位常用的方法···············································105
6.2時(shí)間差定位方法··················································································107
7特高頻檢測技術(shù)在GIS局部放電狀態(tài)監(jiān)測中的應(yīng)用····························121
7.1概述·····································································································121
7.2 GIS局部放電特高頻檢測技術(shù)的應(yīng)用···············································123
7.3 GIS局部放電特高頻檢測典型案例分析···········································126
參考文獻(xiàn)··············································································································182
書單推薦
