大型發(fā)變組定子繞組接地保護(hù)的研究.pdf

1、華北電力大學(xué)（保定）碩士學(xué)位論文大型發(fā)變組定子繞組接地保護(hù)的研究姓名：侯有韜申請(qǐng)學(xué)位級(jí)別：碩士專業(yè)：電力系統(tǒng)及其自動(dòng)化指導(dǎo)教師：張舉20031201華北電力大學(xué)碩士學(xué)位論文摘要1摘要定子繞組單相接地故障是發(fā)電機(jī)最常見的一種故障而且往往是更為嚴(yán)重的繞組內(nèi)部短路故障發(fā)生的先兆本文在對(duì)基波零序電壓型定子接地保護(hù)三次諧波電壓型定子接地保護(hù)和外加電源式定子接地保護(hù)各種方案的構(gòu)成原理及其優(yōu)缺點(diǎn)進(jìn)行分析的基礎(chǔ)上詳細(xì)分析了影響基波零序電壓型定子接地保護(hù)

2、的各種因素并提出了相應(yīng)措施詳細(xì)分析了中性點(diǎn)經(jīng)消弧線圈加串聯(lián)電阻接地方式對(duì)接地電流和傳遞過電壓的抑制作用詳細(xì)推導(dǎo)了水輪發(fā)電機(jī)中性點(diǎn)位移電壓的特征及其與三相對(duì)地電容不對(duì)稱性之間的關(guān)系以外加20Hz交流電源的定子接地保護(hù)為例在不同中性點(diǎn)接地方式下對(duì)電源內(nèi)阻和變壓器參數(shù)的影響作了詳細(xì)分析和仿真關(guān)鍵詞發(fā)電機(jī)定子接地保護(hù)靈敏度ABSTRACTStatgroundfaultisthemostcommongeneratfaultitisthedirec

3、tcauseofphasetophasefaultwhichmayimmediatelydamagegenerat.Protectionschemesbasedonthezerosequencefundamentalvoltagethethirdharmonicvoltagetheinjectionvoltagearepresentedinthispaperbasedonwhichthefactswhichaffectstheprote

4、ctionschemesbasedonthezerosequencefundamentalvoltagetherelevantmeasuresispresented.Thispaperalsodiscussesanothernewneutralgroundingmethodaneutralizerwithseriesresistancewhichcanlimitthegroundfaultcurrentdecreasethetransf

5、erringovervoltageeffectively.Itisdeducedindetailthattheacteristicsofthehydrogeneratneutraldisplacementvoltagetherelationshipbetweenthedisplacementvoltagetheasymmetryofthreephasedistributedcapacitance.Takethe20Hzinjection

6、voltagefexamplethispaperdetailedlyanalyzesimulatetheinfluenceofthesourceinternalresistancethetransfmer’sparameterunderdifferentneutralgroundingmethods.HouYoutao(AutomationofElectricPowerSystems)DirectedbyProf.ZhangJuKEYW