基于matlab的变压器运行特性仿真分析

I基于matlab的变压器运行特性仿真分析摘要变压器是电力系统中不可缺少的重要电气元件，变压器的运行特性也影响着电力系统的性能和正常运行，因此，要对变压器的运行特性进行分析，尤其是变压器的暂态运行特性，因为在暂态的过度过程中可能会出现较大的过电压或过电流，可能会损坏变压器。随着科学技术的发展，仿真技术也得到了很大程度的发展，不再仅仅局限于传统的物理仿真，而是更加方便简洁也更加精确的计算机仿真。本文先是对变压器的稳态和暂态运行特性进行分析，然后运用matlab软件，通过编写matlab程序实现对变压器暂态运行特性的仿真分析，主要包括变压器空载合闸到电源和变压器突发短路这两种情况，对于变压器空载合闸到电源这种情况又通过区分铁心是否饱和，分别用解析法和四阶龙格库塔算法进行仿真，保证了结果的准确可靠。而对于磁化曲线，则采用插值法实现对不饱和区磁化曲线的拟合，饱和区的磁化曲线采用直线代替。并对仿真得到的结果结合理论知识进行了简单的分析，找到了在变压器的过渡过程中对变压器最不利的情况，并且也和理论相对比，验证了所采用仿真方法的正确性和可行性。关键词：变压器，暂态运行特性，空载合闸，突发短路，matlab仿真IIBASEDONTHEMATLABSIMULATIONANALYSISOFTRANSFORMERRUNNINGCHARACTERISTICSABSTRACTTransformerisanimportantandindispensableelectricalcomponentsinthepowersystem,theoperationofthetransformeralsoaffectsthenormaloperationofpowersystem,therefore,weshouldanalyzetherunningcharacteristicsofthetransformer,especiallythetransientstatecharacteristicofthetransformer,becausethatduringthetransientprocessmayappearlargerover-voltageorover-current,whichmightcausesomethingwrongtothetransformer.Withthedevelopmentofscienceandtechnology,thesimulationtechnologyhasbeendevelopedgreatly,andithasbeennolongerlimitedtothetraditionalphysicalsimulation,butamoreconvenientandconcisecomputersimulationwhichismoreaccurate.Thisarticlefirsttothetransformerofatheoreticalanalysisofsteadystateandtransientoperationcharacteristics,andthenusematlabsoftware,bywritingthematlabprogramtorealizethesimulationanalysis,thecharacteristicsofthetransformertransientoperationincludingtransformerno-loadclosingtothepowersupplyandthesuddenshortcircuitofthetransformerinbothcases,thetransformerno-loadclosingtothiskindofsituationandpowersupplybydistinguishwhetherironcoresaturation,respectively,usinganalyticmethodandthefourthorderrungekuttaalgorithmsimulation,ensuretheaccurateandreliableresults.Forthemagnetizationcurve,theinterpolationmethodwasadoptedtorealizetheunsaturatedzoneofmagnetizationcurvefitting,thesaturatedareaUSESthestraightlineinsteadofthemagnetizationcurve.Andthesimulationresultsarecombinedwiththeoreticalknowledgehascarriedonthesimpleanalysis,IIIfoundintheprocessofthetransitionofthetransformeroftransformeristhemostunfavorablesituation,andalsocompared,andthetheorysimulationmethodusedtoverifythecorrectnessandfeasibility.KEYWORDS:transformer,thetransientstatecharacteristic,no-loadclosing,suddenshortcircuit,thematlabsimulationIV目录第1章绪论.........................................................................1§1.1本课题研究的目的和意义.......................................1§1.2国内外研究现状......................................................1§1.3本文研究的主要内容...............................................2第2章Matlab软件..............................................................3§2.1Matlab简介.............................................................3§2.2Matlab的特点..........................................................4§2.3微分方程求解的仿真算法.......................................5§2.3.1Euler法...........................................................5§2.3.2Rungekutta法.................................................5第3章变压器稳态、暂态运行特性分析.....................................7§3.1变压器概述.............................................................7§3.2变压器各电磁量正方向的规定................................7§3.3变压器空载运行......................................................8§3.3.1主磁通、漏磁通.............................................9§3.3.2主磁通和漏磁通的感应电动势........................9§3.3.3空载运行时的电压方程和等效电路..............10§3.3.4铁心饱和和磁滞现象对励磁电流的影响.......11§3.4变压器负载运行.....................................................15§3.4.1负载时的磁动势...........................................15§3.4.2折合算法......................................................16§3.4.3负载运行时的电压方程和等效电路..............17§3.5变压器参数的确定................................................18§3.5.1变压器的空载试验........................................18§3.5.2变压器的短路试验........................................19§3.6变压器的运行性能................................................20§3.6.1变压器的外特性...........................................20§3.6.2变压器的效率特性........................................22V§3.7三相变压器...........................................................23§3.7.1三相变压器的磁路系统................................23§3.7.2三相变压器空载运行时的电动势波形...........23§3.8变压器过渡过程中的过电流现象..........................25§3.8.1变压器空载合闸到电源................................26§3.8.2突发短路......................................................28第4章基于Matlab的变压器动态特性仿真.......................30§4.1变压器空载合闸到电源时过电流的仿真和分析.....30§4.1.1不考虑铁心饱和时变压器空载合闸到电源的过电流仿真..............................................................30§4.1.2考虑铁心饱和时变压器空载合闸到电源的过电流仿真.................................................................36§4.1.3空载合闸到电源时产生的过电流对变压器的影响.........................................................................42§4.2突发短路时过电流的仿真和分析..........................42§4.2.1突发短路时过电流的仿真.............................42§4.2.2突发短路时产生的过电流对变压器的影响...45§4.3变压器动态特性仿真分析.....................................45总结................................................................................47参考文献..........................................................................