電力系統(tǒng)繼電保護(hù)基礎(chǔ)BasicsofPowerSystemRelay

Protection情境三：繼電器結(jié)構(gòu)及工作原理Scenario3:Structureandworkingprincipleof

Relay"

電磁型繼電器的結(jié)構(gòu)和工作原理“電磁型繼電器按其結(jié)構(gòu)分為三種Structureandworkingprincipleofelectromagnetic

relayElectromagneticrelaysareclassifiedintothreetypesaccordingtotheirstructure（a）螺管繞組式Solenoidwinding

type（b）吸引銜鐵式Attractingarmature

type（c）轉(zhuǎn)動(dòng)舌片式Rotatingtongue

type1 在電流保護(hù)中常用DL-10系列電流繼電器DL-10seriescurrentrelaysarecommonlyusedincurrent

protection一種轉(zhuǎn)動(dòng)舌片式的電磁型繼電器。Anelectromagneticrelaywitharotating

tongue繼電器結(jié)構(gòu)Relay

structure繼電器工作原理Workingprincipleof

relays2工作原理 /Working

principle作用于轉(zhuǎn)軸的電磁轉(zhuǎn)矩M

為其為工作力矩。TheelectromagnetictorqueMactingontherotation

shaftistheoperating

torque.作用于轉(zhuǎn)軸的彈簧轉(zhuǎn)矩為Mth

,起反抗M的作用。ThespringtorqueactingontherotationshaftisMth,whichactsasaresistanceto

M.作用于轉(zhuǎn)軸的摩擦轉(zhuǎn)矩為Mm,始終逆著轉(zhuǎn)動(dòng)的方向。ThefrictiontorqueactingontherotationshaftisMm,whichisalwaysagainstthedirectionof

rotation.繼電器動(dòng)作的條件Conditionsfortheoperationof

relaysKWIMthrM

m

Rmop.rMthrRm

M

m

W KI

re.rKre

=IIop.r

re.r

動(dòng)作電流：能使繼電器動(dòng)作的最小電流稱(chēng)為繼電器的動(dòng)作電流Iop.r為:Operatingcurrent:Thesmallestcurrentthatcancausetherelaytooperateiscalledtheoperatingcurrentofthe

relay,representedbyIop.r

as:繼電器的返回電流：當(dāng)Ir減小到繼電器剛好能夠返回原來(lái)位置的最大電流稱(chēng)為繼電器的返回電流Ire.r為:Thereturncurrentoftherelay:WhenIrdecreasestothemaximumcurrentatwhichtherelaycanreturntoitsoriginalposition,thecurrentiscalledthereturncurrentoftherelay,representedbyIre.r

as:繼電器的返回系數(shù)：繼電器的返回電流Ire.r與動(dòng)作電流Iop.r的比值稱(chēng)為返回系數(shù)，

用Kre表示為：Thereturncoefficientoftherelay:

theratioofthereturncurrentIre.roftherelaytotheoperatingcurrentIop.r

iscalledthereturncoefficientandisrepresentedbyKre

as:電流繼電器的返回系數(shù)恒小于1。在實(shí)際應(yīng)用中，要求繼電器有較高的返回系數(shù)，在0.85~0.90之間。Thereturncoefficientofthecurrentrelayisalwayslessthan1.Inpracticalapplications,therelayis

requiredtohaveahighreturncoefficientbetween0.85and

0.90.21改變彈簧反作用轉(zhuǎn)矩Mth,

即改變動(dòng)作電流調(diào)整把手的位置,可做連續(xù)的調(diào)節(jié)。改變繼電器繞組的連接方法，可串聯(lián)或并聯(lián)。當(dāng)繞組串聯(lián)時(shí)，電流動(dòng)作值較并聯(lián)時(shí)小一倍。3繼電器動(dòng)作電流的調(diào)整Adjustmentof

relayoperatingcurrentChangethespringreactiontorqueMth,i.e.changethepositionoftheoperatingcurrentadjustmenthandle,whichcancontinuouslyadjusttheoperating

current.Changethewaytoconnecttherelaywindings,whichcanbeconnectedinseriesorinparallel.Whenthewindingsareconnectedinseries,thecurrentoperatingvalueistwiceassmallaswhentheyareconnectedin

parallel.(1

)(2

)(3

)(4

)????動(dòng)作時(shí)間短，當(dāng) ??op.??

≥

3時(shí)，動(dòng)作時(shí)間 ≤

0．03s4電磁型繼電器的特點(diǎn)Characteristics

ofelectromagneticrelay返回系數(shù)較高，一般均大于0．85Higherreturncoefficient,

generallygreaterthan0.85per

cent≥

3,Shortoperatingtime,whenoperatingtime≤

0.03sIrIop.??消耗功率小，在最小整定值時(shí)，消耗功率為0．1VASmallpower

consumption,

powerconsumptionof0.1VA

in

theminimumsetting

value整定點(diǎn)動(dòng)作值與整定值誤差不超過(guò)±3％Theerrorbetweentheoperatingvalueatthesettingpointandthesettingvalueisnomorethan

±3%1 電磁型電壓繼電器的結(jié)構(gòu)及其工作原理Structureandworkingprincipleofelectromagneticvoltage

relay電磁式電壓繼電器構(gòu)造和工作原理與DL—10系列電流繼電器基本上相同，不同的只是電壓繼電器繞組匝數(shù)多、導(dǎo)線細(xì)，阻抗大，反應(yīng)的參數(shù)是電網(wǎng)電壓。ThestructureandworkingprincipleoftheelectromagneticvoltagerelayisbasicallysamewiththeDL-10seriescurrentrelay.Thedifferenceisthatthevoltagerelayiswithmorewindingturns,finerwire,lagerimpedance,anditsresponseparameteristhegrid

voltage.2過(guò)電壓繼電器的返回系數(shù)恒小于1，一般也在0．85左右。低電壓繼電器的返回系數(shù)恒大于1，一般情況不大于1．2。用于強(qiáng)行勵(lì)磁的不大于1．06。電壓繼電器的動(dòng)作電壓、返回電壓和返回系數(shù)Operatingvoltage,returnvoltageandreturncoefficientofvoltagerelay電壓繼電器分為過(guò)電壓繼電器和低電壓繼電器，它的返回系數(shù)Kre為:Voltagerelayisdividedintoover-voltagerelayandlowvoltagerelay,withreturncoefficientrepresentedbyKre

as:Thereturncoefficientofover-voltagerelayisalwayslessthan1,generallyaround

0.85.Thereturncoefficientoflowvoltagerelaysisalwaysgreaterthan1,butgenerallynotgreaterthan1.2.Thoseusedforforcedexcitationarenotgreaterthan

1.06.時(shí)間繼電器用來(lái)建立必須的動(dòng)作時(shí)限Timerelaysareusedtoestablishthenecessarytimelimitsforoperation為了縮小時(shí)間繼電器尺寸，它的繞組一般不按長(zhǎng)期通電設(shè)計(jì)。Inordertoreducethesizeofthetimerelay,itswindingisgenerallynotdesignedforlong-termenergisation.1在使用時(shí)間繼電器時(shí)，要求：Requirementswhenusingtime

relays:時(shí)間繼電器的動(dòng)作電壓應(yīng)不大于70％額定電壓值，返回電壓應(yīng)不小于5％額定電壓值，交流時(shí)間繼電器動(dòng)作電壓應(yīng)不大于85％額定電壓值

。Theoperatingvoltageofthetimerelayshouldbenogreaterthan70%oftheratedvoltagevalue;thereturnvoltageshouldbenolessthan5%oftheratedvoltagevalue;theoperatingcurrentoftheACtimerelayshouldbenogreaterthan85%oftheratedvoltage

value.2要求測(cè)量值與整定值時(shí)間誤差不超過(guò)0．07s。Thetimeerrorbetweenthemeasuredvalueandthesetvalueshouldnotexceed

0.07s.中間繼電器的作用是增加觸點(diǎn)數(shù)量和容量““Theroleoftheintermediaterelayistoincreasethenumberandcapacityof

contacts信號(hào)繼電器用作動(dòng)作指示，根據(jù)信號(hào)繼電器發(fā)出的信號(hào)指示，運(yùn)行維護(hù)人員能夠方便地分析事故和統(tǒng)計(jì)保護(hù)裝置正確動(dòng)作次數(shù)。Signalrelayis