阻抗元件Impedanceelement圓特性阻抗元件Circularcharacteristicimpedanceelement目錄頁CONTENTSPAGE全阻抗圓特性01Fullimpedancecirclecharacteristics方向阻抗圓特性02Directionalimpedancecirclecharacteristics偏移阻抗圓特性03Offsetimpedancecirclecharacteristics“”動作區(qū)制動區(qū)圓阻抗特性RjX圓周內(nèi)為阻抗元件的動作區(qū)，圓周外為阻抗元件的制動區(qū)，圓周為動作邊界。圓特性又分為全阻抗圓特性、方向阻抗圓特性和偏移阻抗圓特性。阻抗元件的圓動作特性O(shè)perationcharacteristicsofcircularimpedanceelementsTheinsideofthecircumferenceistheoperationareaoftheimpedanceelement,theoutsideofthecircumferenceisthebrakingareaoftheimpedanceelement,andthecircumferenceistheoperationboundary.Circlecharacteristicsarefurtherdividedintofullimpedancecirclecharacteristics,directionalimpedancecirclecharacteristicsandoffsetimpedancecirclecharacteristics.01全阻抗圓特性Fullimpedancecirclecharacteristics保護范圍/Rangeofprotection

“全阻抗圓特性Fullimpedancecirclecharacteristics01

全阻抗圓特性Fullimpedancecirclecharacteristics全阻抗圓特性Fullimpedancecirclecharacteristics01保護動作沒有方向性withnon-directionalprotectionoperation幅值比較式Amplitudecomparisonformula與and動作阻抗Operatingimpedance整定阻抗settingimpedance特點Feature

全阻抗圓特性阻抗元件的動作條件Operatingconditionsoffullimpedancecircularcharacteristicimpedanceelement01相位比較式:Phasecomparisonformula

圖1Figure1圖2Figure2全阻抗圓特性Fullimpedancecirclecharacteristics(2)全阻抗圓特性阻抗元件的動作條件Operatingconditionsoffullimpedancecircularcharacteristicimpedanceelement方向阻抗圓特性Directionalimpedancecirclecharacteristics02方向阻抗圓特性是以保護安裝處為坐標原點，整定阻抗為直徑，且圓周通過坐標原點的圓。“方向阻抗圓特性Directionalimpedancecirclecharacteristics02Thedirectionalimpedancecirclecharacteristicisacirclewiththerelaylocationasthecoordinateorigin,thesettingimpedanceasthediameter,andwithcircumferencepassingthroughthecoordinateorigin.方向阻抗圓特性Directionalimpedancecirclecharacteristics02

為使阻抗元件工作在最大靈敏角條件下，常將阻抗元件的最大靈敏角整定為線路阻抗角。Whenφrisequaltothesettingimpedanceangleφset,thevalueofzristhelargest,equaltozset.Atthistime,theprotectionrangeoftheimpedanceelementisthelargestandtheoperationisthemostsensitive.Therefore,themeasuredimpedanceangleφratthistimeiscalledthemaximumsensitivityangleoftheimpedanceelement,whichisoftenexpressedasφs.Inordertomaketheimpedanceelementworkundertheconditionofmaximumsensitivityangle,themaximumsensitivityangleoftheimpedanceelementisoftensettothelineimpedanceangle.方向阻抗圓特性Directionalimpedancecirclecharacteristics02正方向短路時，測量阻抗Zr在第Ⅰ象限，如故障在保護范圍內(nèi)，Zr落在圓內(nèi)，阻抗元件動作。反方向短路時，測量阻抗Zr在第Ⅲ象限，阻抗元件不動作。因此這種阻抗元件具有很好的方向性。方向阻抗圓特性的特點/CharacteristicsofdirectionalimpedancecirclecharacteristicsWhenthereisashortcircuitintheforwarddirection,themeasuredimpedanceZrisinthefirstquadrant.Ifthefaultiswithintheprotectionrange,ZrfallswithinthecircleandtheimpedanceelementoperatesWhenshort-circuitedinthereversedirection,themeasuredimpedanceZrisinthethirdquadrant,andtheimpedanceelementdoesnotoperate.Thereforethisimpedanceelementhasgooddirectivity方向阻抗圓特性Directionalimpedancecirclecharacteristics02方向阻抗圓特性的特點/Characteristicsofdirectionalimpedancecirclecharacteristics當保護安裝處發(fā)生短路故障時，Ur=0,Zr=0因此，該特性的阻抗元件在保護安裝處有“死區(qū)”。阻抗元件不動作Therefore,theimpedanceelementwiththischaracteristichasa"deadzone"attherelaylocation.WhenashortcircuitfaultoccursattherelaylocationtheUr=0,Zr=0andimpedanceelementdoesnotoperate02“”按幅值比較方式的動作條件Operationconditionsbasedonamplitudecomparisonmethod方向阻抗圓特性Directionalimpedancecirclecharacteristics方向阻抗圓特性的動作條件Operationconditionsfordirectionalimpedancecirclecharacteristics(3)02“”按相位比較方式的動作條件Operationconditionsbasedonphasecomparisonmethod圖3/Figure3方向阻抗圓特性Directionalimpedancecirclecharacteristics(4)方向阻抗圓特性的動作條件Operationconditionsfordirectionalimpedancecirclecharacteristics偏移阻抗圓特性O(shè)ffsetimpedancecirclecharacteristics0303“以保護安裝處為坐標原點，以正向整定阻抗????????與反向的整定阻抗???????????的幅值之和|????????|+|??????????|為直徑圓，圓心坐標為??0=1/2(???????????????????)

；半徑為1/2|????????

+??????????|。偏移特性阻抗圓的構(gòu)成Thecompositionoftheoffsetimpedancecircle圖4Figure4偏移阻抗圓特性O(shè)ffsetimpedancecirclecharacteristicsTaketherelaylocationastheoriginofthecoordinates,isacirclewiththesumoftheamplitudesoftheforwardsettingimpedance????????

andthereversesettingimpedance???????????

and|????????|+|??????????|

asthediameter,andthecoordinateofthecenterofthecircleis??0=1/2(???????????????????)

;Theradiusis1/2|????????

+??????????|03“特點

/Features偏移特性阻抗圓的構(gòu)成Thecompositionoftheoffsetimpedancecircle圖4Figure4保護動作在一定范圍內(nèi)有方向性，且消除了保護安裝處的“死區(qū)”α稱為偏移系數(shù)，是一個小于1的系數(shù)，實用中取0.1~0.2。偏移阻抗圓特性O(shè)ffsetimpedancecirclecharacteristicsTheoffsetimpedancecircleiswithdirectionalprotectionoperationwithinacertainrangeandeliminatesthe"deadzone"attherelaylocation.α

calledtheoffsetcoefficient,whichisacoefficientlessthan1andtakes0.1~0.2inpractice.03“①幅值比較式Amplitudecomparisonformula圖5/Figure5”偏移阻抗圓特性O(shè)ffsetimpedancecirclecharacteristics偏移特性阻抗圓的動作條件Operationconditionsforoffsetimpedancecircle(5)03“②相位比較式Phasecomparisonformula圖6/Figure6“偏移阻抗圓特性O(shè)ffsetimpedancecirclecharacteristics(6)偏移特性阻抗圓的動作條件Operationconditionsforoffsetimpedancecircle已知其動作特性為Itsoperationcharacteristicsareknowntobe12方向阻抗圓特性全阻抗圓特性““

練習SettingtheimpedanceFul