基于复杂网络理论的电力系统连锁故障分析

摘要I摘要随着全球经济的不断发展。电力系统的规模变得越来越大，电网的互联成为电网发展的重要趋势。电网的互联使电力系统的规模越来越大，这提高了电力系统运行效率但同时也增加了电力系统的复杂性。当电网发生局部故障时，故障会迅速传播所波及的范围更广，损失更加严重。连锁故障是引发大停电事故的重要原因，最近大停电事故频发引起了国内外学者的广泛关注。复杂网络理论的兴起为人们研究连锁故障问题提供了一种新的思路，与传统的方法相比能从整体上分析系统的特性，揭示连锁故障传播的内在机理。本文基于复杂网络理论对大规模电网的连锁故障进行研究，首先建立电网的复杂网络模型，通过对系统中薄弱环节的识别，然后进行连锁故障的仿真。文章先对复杂网络中的经典模型及网络的特征参数做简要的介绍，并且详细研究了本文所应用的电网无向加权模型，根据实际电网的拓扑特性及电气性质建立电网的复杂网络模型，进而分析电网的复杂性和故障的内在起因。本文综合了线路电抗与线路容量提出容量介数指标，给出脆弱线路辨识算法，采用线路容量介数指标来辨识电网的脆弱线路，通过对IEEE39节点系统算例的计算仿真并与以往传统拓扑介数法进行对比，验证了本文方法的有效性。本文在原有节点动态模型基础上提出线路动态模型作为连锁故障仿真模型，通过网络效能下降百分比来衡量故障对电网输电能力的影响。应用两种故障模式模拟分析电网自身和外部因素对电网连锁故障的影响，并给出详细算法流程，采用IEEE57和IEEE118节点系统算例进行连锁故障仿真，验证了方法的有效性，根据故障仿真结果，本文还分析了大电网发生连锁故障机理并提出相应的故障缓和策略。关键词：复杂网络；线路介数；脆弱线路；线路动态模型；连锁故障AbstractIIAbstractWiththerapiddevelopmentofglobaleconomy,thesizeofpowergridbecomesmoreandmorelarge,gridinterconnectionbecomesalargescalepowersystem.Theinterconnectionofpowergridcouldimprovetheefficiencyofsystembutalsoincreasethecomplexityofpowergrid,whichleadstothewiderspreadandmoreseriouslossafterfailure.Thefrequentoccurrenceofblackoutsarousestheattentionoftheexpertsandscholarsathomeandabroadwhocareabouttheproblemsoncascadingfailure.Thetraditionalanalysismethodcan'trevealthewholecharacteristicsofsystem.Thedevelopmentofcomplexnetworktheoryprovidesanewperspectiveforthestudyofcascadingfailure,andtheoryofthewholeanalysismethodcananalyzetheglobalnatureofthecascadingfailure.Thelargescalegridcascadingfailuresisstudiedbaseonthetheoryofcomplexnetworkinthispaper.Firstlyestablishacomplexnetworkmodelofthepowergrid,throughtheidentificationofweaklinesinthesystem,thensimulatthecascadingfailures.Theclassicmodelofcomplexnetworkandcomplexnetworkparametersoftenusedinpowersystemwereintroduced,complexnetworkmodelappliedinthispaperwasstudiedindetailandthecomplexityofthepowersystemwasanalyzed.Then,anundirectedandweightedmodelofthepowergridwasestablishedbasedontheprincipleofmodelingpowergrid,thecomprehensiveweightedindexwiththereactanceoflinesandlinecapacitywasproposed.Linecapacitybetweennesswasusedtoidentifythevulnerablelinesofpowergrid,thealgorithmofidentifyingvulnerablelineswasgiven,andtheapplicationoftheIEEE39nodesystemprovedthevalidityoftheidentificationmethod.Finally,linedynamicmodelwasusedasthesimulationmodelforcascadingfailuresimulationbasedontheoriginalnodedynamicmodel.Throughthepercentagedropofnetworkefficiencytomeasureinfluenceontransmissioncapacityofnetwork东北电力大学硕士学位论文IIIafterfailure,twokindsoffailuremodewereappliedtotheanalysisofcascadingfailureofpowergrid,andadetailedalgorithmprocesswasgiven.TheIEEE57andIEEE118nodesystemwereusedforcascadingfailuresimulationtoverifytheaccuracyofthemethod,failuremechanismoflarge-scalepowergridandmitigationstrategieswereanalyzedaccordingtothefaultsimulationresults.Keywords:ComplaxNetwork;LineBetweenness;VulnerableLines;LineDynamicModel;CascadingFailure目录IV目录摘要...............................................................................................................................IAbstract.........................................................................................................................II目第1章绪论.............................................................................................................11.1选题研究背景及意义..................................................................................11.2国内外研究现状和发展趋势......................................................................21.2.1国内外研究现状...............................................................................21.2.2国内外研究的发展趋势...................................................................31.3电网连锁故障的主要研究方法..................................................................31.4本文的主要工作..........................................................................................6第2章复杂网络模型及特性分析.............................................................................82.1引言..............................................................................................................82.2复杂网络模型..............................................................................................82.2.1规则网络模型...................................................................................82.2.2随机网络模型...................................................................................92.2.3无标度网络模型.............................................................................102.2.4小世界网络模型.............................................................................112.3复杂网络的结构统计特性........................................................................142.3.1度与度分布.....................................................................................142.3.2最短路径和平均最短路径长度.....................................................152.3.3聚类系数.........................................................................................162.3.4介数...............................................................................................162.4电力系统的复杂性....................................................................................172.5电网拓扑性质研究