毕业设计英文翻译-使用电超声波技术检测变压器局部放电

译文原文题目TRANSFORMERPARTIALDISCHARGDETECTIONUSINGELECTRICALULTRASONICTECHNOLOGY译文题目使用电超声波技术检测变压器局部放电学院电子信息学院专业班级电气工程及其自动化2009级7班学生姓名李龙龙学号20903040702TRANSFORMERPARTIALDISCHARGEDETECTIONUSINGELECTRICALULTRASONICTECHNOLOGYWEIJIANG,FANLIU,ZHIYUANWANGSICHUANELECTRICPOWERRESEARCHINSTITUTECHENGDU,CHINAABSTRACTPARTIALDISCHARGEPDISUSUALLYHAPPENEDCAUSEDBYFLAWANDDETERIORATIONOFTRANSFORMERINSULATIONITISTHEMAINREASONOFTHEACCIDENTOFTRANSFORMERANDPOWERSYSTEMTHEREFORE,ITSNECESSARYANDIMPORTANTTODETECTTHEPARTIALDISCHARGEOFTRANSFORMERWHILEOPERATINGANDMANUFACTURINGWHENPDOFTRANSFORMERINTERNALINSULATIONOCCURS,ELECTROMAGNETICWAVES,SOUNDWAVESANDOTHERSIGNALSAREPRODUCEDACCORDINGTOSUPERSONICSIGNAL,WECANDETECTTHELOCATIONOFPDBUTTHISMETHODCANNOTTESTTHENUMBEROFCHARGEWITHELECTRICALULTRASONICDETECTIONMETHOD,ITISEASYTOLOCATEPDANDTESTTHENUMBEROFCHARGEINTHISPAPER,AMETHODOFELECTRICALULTRASONICDETECTIONISPRESENTED,WHICHISBASEDTHREEDIMENSIONALSCATTERPOINTANDULTRASONICHITTOTIMETHEMETHODISEFFECTIVETOLOCATEFAULTOFTRANSFORMERINSULATIONTOVALIDATETHEAPPROACH,ACASEISINTRODUCEDKEYWORDSPARTIALDISCHARGEELECTRICALSUPERSONICDETECTIONMETHODPULSECURRENTMETHODPOWERTRANSFORMERINTRODUCTIONPARTIALDISCHARGEISCOMMONONACCOUNTOFFLAWANDDETERIORATIONOFINSULATION,ESPECIALLYINPOWERTRANSFORMER,ANDISTHEMAINREASONOFTHEACCIDENTOFTRANSFORMERANDPOWERSYSTEMTHEREFORE,ITSNECESSARYANDIMPORTANTTODETECTTHEPARTIALDISCHARGEOFTRANSFORMERWHILEOPERATINGANDMANUFACTURINGWHENPDOFTRANSFORMERINTERNALINSULATIONHAPPEN,ELECTROMAGNETICWAVES,SOUNDWAVESANDOTHERSIGNALSAREPRODUCEDATTHESAMETIMETHOUGHDETECTTHEULTRASONICSIGNAL,WECANLOCATETHEPD13PDDETECTIONUSINGULTRASONICSIGNALCANLOCATETHEDISCHARGE,BUTTHISMETHODCANNOTTESTTHENUMBEROFTHEDISCHARGEPARTIALDISCHARGETESTCANEFFECTIVELYTESTTHEDISCHARGE,BUTCANNOTACCURATELOCATE46IFWEUSEPDULTRASONICLOCATIONANDPARTIALDISCHARGETESTATTHESAMETIME,THENUMBERANDLOCATIONOFDISCHARGECANBETESTEDWECALLTHISMETHODISELECTICALULTRASONICTECHNOLOGY710AMETHODOFELECTICALULTRASONICDETECTIONISPRESENTEDINTHISPAPER,WHICHISBASEDTHREEDIMENSIONALSCATTERPOINTANDSUPERSONICHITTOTIMEWITHACASE,THEACCURACYOFPDELECTICALULTRASONICDETECTIONMETHODISDEMONSTRATEDTRANSFORMERPDELECTICALULTRASONICDETECTIONPRINCIPLEWHENPARTIALDISCHARGEOFTRANSFORMERINTERNALISOLATIONOCCURS,THEULTRASONICSIGNALWILLFORMSPHERICALWAVEANDSPREADTOTHESURROUNDINGWITH1400M/SSPEEDINTHETRANSFORMEROILASLONGASPLACEDULTRASONICSENSORSONTHEOUTSIDEOFTRANSFORMERTANKWALL,ULTRASOUNDPRODUCEDBYPDCANRECEIVEWECANLOCATETHEDISCHARGEOFBYDETECTINGULTRASONICSIGNALBUTITHARDTOTESTTHENUMBEROFTHEDISCHARGEONLYBYULTRASONICSIGNALPARTIALDISCHARGETESTBASEDONPULSECURRENTMETHODCANNOTACCURATELOCATEDISCHARGESOURCE,THOUGHITCANEFFECTIVELYTESTTHEDISCHARGESO,ELECTRICALULTRASONIC,THATDETECTBOTHULTRASONICSIGNALANDPULSECURRENTDISCHARGE,CANREALIZETOTESTTHENUMBERANDLOCATIONOFDISCHARGETHEDETECTIONPRINCIPLEINFIGURE1FIG1TRANSFORMERPDELECTICALULTRASONICDETECTIONPRINCIPLEAPARTIALDISCHARGEULTRASONICLOCATIONPDULTRASOUNDLOCATIONMETHODISTHATPLACINGULTRASONICSENSORSONAFEWPOINTSOFTHETRANSFORMERTANKSHELL,COMPOSEDOFACOUSTICARRAYTOMEASURETHESPREADTIMEORRELATIVETIMEOFEACHSENSOR,THENACCORDINGTOTHETIMETOSOLVEEQUATIONSOFPDSOURCELOCATIONFIG2TRANSFORMERPDULTRASONICDETECTIONPRINCIPLEWECANSEEFROMFIG2SETTHECOORDINATEOFDISCHARGESOURCELOCATIONISP（X,Y,Z）,THETRANSFORMERLENGTH,WIDTHANDHEIGHTAREM,NANDHTHEREARESIXSENSORSONTHETRANSFORMERTANKSHELLTHEIRCOORDINATESARE（0,）,（,N,）,（,0,）,1PY1Z2PX2Z3X3Z（M,）,（,0）,（,0）SO,THESTRAIGHTLINEDISTANCEFROMTHESIX4PY4Z5PX5Y0X0SENSORSTOPDSOURCEARE（1）22000SXYZ（2）111（3）2222SXYNZ（4）333（5）222444SXMYZ（6）555SET，ARETHETIMEDIFFERENCEBETWEENPDSOURCETO、1T23T4T61P2、ANDPDSOURCETOSETVISTHEULTRASONICSPEEDTHEREFORE3P450P（7）101ST（8）202SVT（9）33（10）404SVT（11）55WECANDETERMINETHELOCATIONSOF，WHENWESETTHESENSORSON0P1234P5TRANSFORMERTANKSHELLTHETIMEDIFFERENCEOFCANBEBETWEEN，AND1234P50CANBEMEASUREBYMULTICHANNELOSCILLOSCOPESO,THELOCATIONOFPDSOURCECANBEGETBYSOLVEFORMULA（1）（11）BECAUSETRANSFORMERINTERNALSTRUCTUREISCOMPLEX,WHICHISCOMPOUNDOFDIFFERENTMATERIALS,SUCHASOIL,COPPER,SILICONSTEELANDSOONULTRASOUNDPROPAGATIONPATHISNOTCOMPLETELINEAR,BUTITISINCLUDESOMEREFRACTIONBECAUSETHEFREQUENCYOFULTRASOUNDISVERYHIGH,REFRACTIONISVERYSMALLTHEREFORE,BYULTRASOUNDSIGNAL,WECANACCURATELYDETECTTHELOCATIONOFPARTIALDISCHARGEMORESENSORSWEUSE,MOREACCURATELOCATIONWEGETBTRANSFORMERPARTICALDIDCHARGETEST1TESTMETHODPARTIALDISCHARGETESTUSINGPOWERSUPPLYOFFIVETIMESTHEFREQUENCY,250HZ,APPLYTESTVOLTAGEINTHETRANSFORMERLOWVOLTAGEWINDINGADETECTIONIMPEDANCEARECONNECTEDTOTHEFINALLAYEROFTESTEDCASINGINSULATINGPAPER,THENLINKTOTHEPDTESTAPPARATUSBYDATACABLETOSUPPLEMENTTHETRANSFORMERCAPACITIVECURRENT,SOMEREACTORSAREPARALLELEDTOTHETRANSFORMERLOWVOLTAGESIDE,WHEREISAPPLIEDTESTVOLTAGEBEFORETHETEST,ASQUAREWAVE,WITH500PCCHARGE,AREINJECTEDINTOTHEHIGHMEDIUMVOLTAGEFINALLAYEROFTESTEDCASINGINSULATINGPAPERTOCALIBRATEDTHENUMBEROFDISCHARGESETTINGPDTESTAPPARATUSTOADJUSTPD100METERGAUGESHOWSFULLSCALEGRID,WHICHINDICATED500PCDISCHARGETRANSFORMERPDTESTPRINCIPLEUSINGPULSECURRENTMETHODISSHOWNINFIG3FIG3TRANSFORMERPDTESTPRINCIPLEUSINGPULSECURRENTMETHOD2TESTVOLTAGESETISTHEMAXIMU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FTHE,WE5MUMONITORTHECURRENTSOFTHECOMPENSATINGREACTORANDTRANSFORMERACCORDINGTOTHESIZEOFTHESETWOCURRENTSTOINCREASEORDECREASETHECOMPENSATIONREACTORCAPACITY3RESULTSOFPARTIALDISCHARGETESTPARTIALDISCHARGETESTOFTRANSFORMERPHASEASHOWTHATWHENTESTVOLTAGEINCREASEDTO116KVABOUT,THEPARTIALDISCHARGEREACHED618PCANDEXCEEDED500PCTHATISTHEAMOUNT083MUOFPARTIALDISCHARGELIMITSPROVIDEDBYGB501502006“INSTALLATIONOFELECTRICALINSTALLATIONSELECTRICALEQUIPMENTTRANSFERTESTINGSTANDARD“FIG8THENUMBEROFPARTIALDISCHARGEAT173MUTHENUMBEROFPARTIALDISCHARGEREACHED5010PC,WHENTESTVOLTAGEINCREASEDTO173MUDISCHARGEPULSESWEREINTHEFIRSTANDTHIRDQUADRANTANDTHEYWERESYMMETRIC,WHICHISTHETYPICALPDPATTERN,SHOWNINFIG8THEREFORE,WECANDETERMINETHATTHEREISTRANSFORMERINSULATIONFAILUREINPHASEACOMBINEDWITHULTRASONICLOCATION,THELOCATIONOFPARTIALDISCHARGECANBEDETECTEDCRRSULTOFELECTICALULTRASONICDETECTIONWITHULTRASONICSIGNALSOFTRANSFORMERINSULATIONFAULTRECEIVEDBYEACHSENSORS,ANDTHREEDIMENSIONALSCATTERPLOTOFPARTIALDISCHARGEPOINT,WECANSEETHATTHEREISPARTIALDISCHARGEINTHEVICINITYOFCOMICHIGHSEATOFTRANSFORMERPHASEACCORDINGTOPARTIALDISCHARGETESTDONEATTHESAMETIME,WEKNEWTHENUMBEROFTRANSFORMERPARTIALDISCHARGEISFAREXCEEDSTHEPARTIALDISCHARGELIMITSINTHENATIONALSTANDARDELECTRICALULTRASONICCANTESTTHENUMBERANDLOCATIONOFDISCHARGEITGOODTOPREVENTACCIDENTSCAUSEDBYTRANSFORMERINSULATIONFAILUREANDTOCARRYOUTREPAIRWORKCONCLUSIONAMETHODOFELECTICALULTRASONICDETECTIONISPRESENTEDINTHISPAPER,WHICHISEFFECTIVETOLOCATETRANSFORMERINSULATIONFAULTACASEISINTRODUCEDTOVALIDATETHEACCURACYOFELECTICALULTRASONICDETECTIONDETECTINGULTRASONICSIGNALPRODUCEDBYPDCANLOCATETHEDISCHARGE,BUTTHISMETHODCANNOTTESTTHENUMBEROFDISCHARGEPARTIALDISCHARGETESTCANEFFECTIVELYTESTTHEDISCHARGE,BUTCANNOTACCURATELOCATEWITHELECTICALULTRASONICDETECTIONMETHOD,ITISEASYTOLOCATEPDANDTESTTHENUMBEROFCHARGE,WHICHCANEFFECTIVELYASSESSTHESTATUSOFTRANSFORMERINSULATIONREFERENCES1XIAORONGWANG,BEIWEI,GUANJUNWANGANEWPARTIALDISCHARGEELECTRICALLOCATIONMETHODOFTRANSFORMERWINDINGHIGHVOLTAGETECHNOLOGY1999,25327292BENGTSSONCSTATUSANDTRENDSINTRANSFORMERMONITORINGIEEETRANSACTIONONPOWERDELIVERY1996,113137913843TATSUOTAKADA,ACOUSTICANDOPTICALMETHODFORMEASURINGELECTRICCHARGEDISTRIBUTIONSINDIELECTRICSIEEETRANSACTIONSONDIELECTRICSANDELECTRICALINSULATION,1999,655195474CAIXINSUN,WENQIZHAOELECTRICALACOUSTICANDACOUSTICACOUSTICLOCATINGMETHODOFTRANSFORMERPDSOURCEANDITSEVALUATIONSTUDYTRANSACTIONSOFCHINAELECTROTECHNICALSOCIETY1997,1254952,605HGKRANZ,APDMEASURINGANDEVALUATIONSYSTEMBASEDONDIGITALSIGNALPROCESSINGIEEETRANSACTIONSONDIELECTRICSANDELECTRICALINSULATION,2000,7121296YANGXU,MINGYU,XIAOLONGCAO,ETALPARTIALDISCHARGEPULSEMEASUREMENTSANDCOMPARISONWITHTHEELECTRICALMEASURINGMETHODHIGHVOLTAGETECHNOLOGY2001，274347TBOCZAR,IDENTIFICATIONOFSPECIFICTYPEOFPDFROMACOUSTICEMISSIONFREQUENCYSPECTRAIEEETRANSACTIONSONDIELECTRICSANDELECTRICALINSULATION,2001,845986068BARRYHWARDASURVEYOFNEWTECHNIQUESININSULATIONMONITORINGOFPOWERTRANSFORMERSIEEEELECTRICALINSULATIONMAGAZINE,2001，17316239YANPENGHAO,GUOLIWANG,HENGKUNXIE,ETALSTUDYONAGINGPROPERTIESOFSTATORINSULATIONBASEDONPARTIALDISCHARGEANDULTRASONICMETHODTRANSACTIONSOFCHINAELECTROTECHNICALSOCIETY2002,17,21610CAIXINSUN,BINGLUO,WENLINZHAOSTUDYONULTRASONICHIGHSENSITIVITYSENSORFORTRANSFORMERPARTIALDISCHARGESOURCELOCATIONCHINESEJOURNALOFSCIENTIFICINSTRUMENT1997,185453458使用电超声波技术检测变压器局部放电WEIJIANG,FANLIU,ZHIYUANWANGSICHUANELECTRICPOWERRESEARCHINSTITUTECHENGDU,CHINA摘要局部放电（PD）是通常由变压器绝缘的缺陷和恶化引起。它是变压器和电力系统事故的主要原因。因此，当变压器在运行时，检测变压器局部放电是非常必要的和重要的。当变压器内部绝缘发生局部放电时，会产生电磁波、声波等信号。用电超声波方法，很容易找到局部放电位置和电量。本文提出了一种基于三维散射点和超声波冲击时间的电超声波检测方法。下面用一个例子来验证这种方法。关键词局部放电，电超声波检测方法脉冲电流法电力变压器1引言由于绝缘缺陷和恶化，局部放电是常见现象,尤其是在电力变压器中,是变压器和电力系统事故发生的主要原因。因此，在操作和制造变压器时，检测局部放电是很有必要和重要的。当变压器内部绝缘局部放电发生，电磁波，同时产生的声波和其他信号。虽然超声波检测信号，我们可以找到局部放电。利用超声波信号的局部放电检测可以定位放电位置，但这种方法不能测试放电量。局部放电试验可以有效地检测放电量，但不能准确定位局部放电。如果我们使用局部放电超声定位的同时，使用局部放电试验，放电的位置和量数都可以测试。我们称这种方法为电超声波技术。本文提出了一种基于三维散射点和超声波冲击时间的电超声波检测方法，并用一个例子来证电超声波技术检测局部放电。2变压器局部放电超声波检测原理当变压器内部绝缘局部放电发生时，超声波信号将形成球面波，并以1400M/S的速度在变压器油箱中传播。只要把超声波传感器放在变压器油箱壁外，就可以接受由局部放电产生的超声波。我们可以通过检测超声波信号定位局部放电，但是仅用超声波信号很难测试放电量，基于脉冲电流局部放电检测方法不能准确定位放电来源，但它能有效测试放电量。所以，同时检测超声波信号和脉冲电流放电的电超声波检测技术，能够检测出放电位置和放电量。检测原理如图1所示。图1变压器局部放电的电超声波检测原理（1）超声波定位局部放电局部放电超声波定位法是在变压器箱壳的几个点上放置传感器，组成声阵列来测量每个传感器的传播时间和相对时间，然后根据时间来解方程中局部放电的位置。图2变压器局部放电超声波检测原理从图2知，设放电源的坐标位置为P（X,Y,Z）,变压器的长、宽、高分别为M、N、H，变压器箱壳上有六个传感器，它们的坐标分别为（0,）,（1PY1Z2P,N,）,（,0,）,（M,）,（,0）,（,0），因此2XZ3PX3Z44YZ5X5Y0X0它们距放电源的位置分别为（1）22000SXYZ（2）111（3）2222SXYNZ（4）333（5）222444SXMYZ（6）555设放电源传播到、的时间分别为，0P1234P1T23T4，V为超声波速度。则5T6（7）101SVT（8）22（9）303SVT（10）404SVT（11）55当在变压器箱壳上放置传感器时，可决定、的位置，0P1234P5用多通道示波器测量和、的时间，因此，放电源的位置可0P12345由公式（1）（11）解出。因为变压器内部结构很复杂,这是复合不同的材料,如石油、铜、硅钢等等。超声波传播路径不是完整的线性,但它是包括一些折射。因为超声波的频率非常高,折射是非常小的。因此,通过超声波信号,我们可以精确地检测到局部放电的位置。我们使用多个传感器,更多我们得到准确的位置。（2）变压器局部放电测试测试方法局部放电测试用电源的五倍频率250HZ,施加试验电压在变压器的低压绕组。检测阻抗连接到测试的最后一层套管绝缘纸，然后链接到通过数据电缆测试仪。为了补充变压器的容性电流，将一些电抗器并联到变压器低压侧，当作测试电压。在测试之前，将方波与500PC电荷充电，注入高（中）电压最后一层壳体绝缘纸校准放电的数目。设置局部放电测试仪器，调整局部放电100M表显示满刻度格，表示500PC放电。变压器局部放电测试原理，在图3中示出了采用脉冲电流的方法。LAXAM1Z2ZC地局部放电测试装置图3脉冲电流法的变压器局部放电测试原理测试电压设为最大工作电压，打开电源时，不MU173MU153MU小于，维持这种电压五分钟，到维持24分钟，然后2313PMP1把电压降到，维持这种电压，至少五分钟，测试变压器局部放电量，最后把2U电压降低到，维持这种电压五分钟，当小于时关掉电源，在整13M23U个放点期间检测局部放电。测试补偿考虑到变频电源单元和可能的共振的能力，放电反应器用于在测试补偿电容电流。根据实际发电能力，所需的功补偿可以由以下公式计算。（12）2CQCU使用电抗器以补偿电容电流。电压高达20和50的期间，监控173MU补偿电抗器和变压器的电流，并决定增加或减少补偿电抗器的容量。3电超声波局部放电检测的例子一个220KV变电站1电力变压器油中乙炔过量。随访检查发现，乙炔仍然超标，且有进一步增加的趋势。内绝缘的变压器可能存在局部放电现象。为了防止变压器发生故障，电源伴侣停止变压器，由李政超声波检测方法，评价其绝缘状态，并检测可能的局部放电定位。（1）超声波局部放电现场测试局部放电试验中，超声波PD现场测试进行24通道超声波局部放电检测与显示系统。变压器建模和传感器的位置设定坐标原点沿变压器高压侧的槽的右下角。从图4我们可以看到，X轴的正方向沿罐壁，C相朝向B相，Y轴方向上垂直正交于罐底。Z轴垂直于罐壁由外而内的。试验变压器的长度是886M，宽为275M，高为356M。建立了变压器的几何模型为X886M，Y356M和Z275M。图4变压器局部放电定位坐标使用RI5I传感器，它有18个通道，内置40DB的超声波脉冲和谐振频率为150KHZ的前置放大器。有六个传感器放置在变压器的正和负的表面，四个传感器放在两侧，变压器，和两个传感器放置在变压器底部。完成传感器放置后，变压器的三维模型如图5所示。图5变压器传感器的三维模型参数设置超声波检测变压器绝缘故障的参数设置有阈值、声音速度、采样率、过滤范围等等。设置超声波信号的振幅是45DB,浮动阈值是4DB。由于变压器铁心的磁噪声能量集中在1065KHZ的频率范围和变压器的噪声集中在低于15KHZ的频带，在15KHZ附近最强的频带。至1KHZ滤波器的频率模拟滤波器设置下限，上限为400KHZ，采样率为1MSPS。设置超声波信号的速度是1400M/S，最小的影响是4M/S和最大的影响M/S。根据期望输出值,我们可以设置冲击时间、精力,振幅,三维散点图等。该测试使用多通道显示，这有利于分析和比较找到变压器的绝缘故障。局部放电测试结果需要花6个小时来定位变压器绝缘故障。测试时有明显的突然和高振幅声发射信号，超声波信号幅度的分布是一个大范围,最大振幅是2810DB。信号触发频繁，一些频道总能捕获信号。通道1、2、7、8、13、14有局部放电信号特性。这六个通道信号满足超声信号特征，通道7和14的超声波信号振幅更大，分别为1892DB和2810DB。因此,我们认为这六个频道可能收到了局部放电信号和对应的放电点集中在不久的块漫画高变压器相一个。图7变压器绝缘故障定位的散点图图7显示放电点集中在信道1,2,7,8,13,14并符合传感器接收的结果。所以，如果有变压器绝缘局部放电，它应该集中在变压器A相，局部放电数漫画高座位附近可以通过局部放电试验同时进行测试。（2）变压器局部放电量测试当我们用变压器绝缘超声波检测时,同时进行局部放电测试，测试局部放电量。变压器主要参数型号SFPSZ7120000/220额定电压（2208125）/121/105KV额定容量120/120/60MVA连接组别01NNYYD计算测试电压高压绕组电力系统最大工作电压25HMVUK测试电压13518H中压绕组电力系统最大工作电压26LMVK测试电压131509LU高压绕组0244AK中压绕组3698MV测试电压倍数2145K低压绕组测试电压3860ACSKU中压绕组测试电压）0125189AMV补偿估计考虑倍频电源和可能的共振能力，在测试过程中无放电反应器，使用无功功率补偿。用16000PF电容补偿无功功率容量。21232314506809167CQCUKVAR使用反应器补偿，当电压达到20和50的，我们监测的补偿电抗器5MU和变压器的电流，根据这两个电流的大小来增加或减少的补偿电抗器的容量。局部放电测试结果局部放电试验变压器相显示，当测试电压上升至116KV（大约为）083MU，局部放电达到618PC是局部放电量的限制，所提供的GB501502006“电气装置安装超过500个电气设备传输测试标准“。图8电压为时的局部放电量173MU局部放电的数目达到5010PC，当测试电压增加至。放电脉冲的173MU第一和第三象限中，它们是对称的，这是典型的局部放电模式，如图8中所示。因此，我们可以判断，A相结合超声定位是变压器绝缘故障，可以检测局部放电的位置。（3）电超声波检测结果随着超声波信号接收各传感器和局部放电点的三维散点图的变压器绝缘故障，我们可以看到有漫画座附近的变压器相局部放电。根据同时进行局部放电试验，我们知道变压器局部放电的数量远远超过了部分排放限值的国家标准。电气超声波可以测试放电的数量和位置。好防止发生意外所造成的变压器绝缘故障，进行维修工作。4总结本文提出了一种电超声波检测法，它是有效的定位变压器绝缘故障。一个案例验证了超声检测的精度的电。由局部放电产生的超声信号进行放电，但这种方法不能测试放电量。局部放电试验可以有效地检测放电量，但不能准确定位。电超声波检测方法，它是容易找到的局部放电位置和测试电量，可以有效地评估变压器绝缘状态。参考文献1XIAORONGWANG,BEIWEI,GUANJUNWANGANEWPARTIALDISCHARGEELECTRICALLOCATIONMETHODOFTRANSFORMERWINDINGHIGHVOLTAGETECHNOLOGY1999,25327292BENGTSSONCSTATUSANDTRENDSINTRANSFORMERMONITORINGIEEETRANSACTIONONPOWERDELIVERY1996,113137913843TATSUOTAKADA,ACOUSTICANDOPTICALMETHODFORMEASURINGELECTRICCHARGEDISTRIBUTIONSINDIELECTRICSIEEETRANSACTIONSONDIELECTRICSANDELECTRICALINSULATION,1999,655195474CAIXINSUN,WENQIZHAOELECTRCALACOUSTICANDACOUSTICACOUSTICLOCATINGMETHODOFTRANSFORMERPDSOURCEANDITSEVALUATIONSTUDYTRANSACTIONSOFCHINAELECTROTECHNICALSOCIETY1997,1254952,605HGKRANZ,APDMEASURINGANDEVALUATIONSYSTEMBASED