Red Warning

Post on 17-Aug-2015

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Schema of PresentationSchema of PresentationIntroductionNeedfor protectionBasic relay operationMethods of protectionTime graded protectionCurrent graded protectionDistance protection Differential protectionCarrier current protectionConclusion08/!/"S#$CObjectiveObjective08/!/" S#$C %&eeder is the line that transfers the po'er from source end to the distri(ution end)To ha*e a uninterrupted po'er supply for consumers+ feeders need to (e protected from *arious faults using different schemes) IntroductionIntroductionThe 'ord &$$D$, may (e referred asthe connecting lin- (et'een the t'o circuits) The feeder could (e in the form of transmission line that is short+ medium+ or long or this could (e a distri(ution circuit)&eeders form theintegral part of po'er system+ as po'er is transferred through feeders from source to load).ence it is important to protect feeders from faults for continuous supply of po'er to consumers)08/!/" ! S#$C08/!/" / S#$C08/!/" " S#$CNeed for protection Need for protection 0*er loading 0*er *oltage 1nder &re2uency Po'er S'ingsTransient &aults Permanent &aults 3tmospheric Conditions4Temperature+ 5ightening6 Short circuit &aults&ollo'ing conditions lead to*arious faults708/!/" 8 S#$CProtective relayProtective relayIt is a de*ice that detects the fault and initiates the operation of the circuit (rea-er to isolate the defecti*e element from rest of the system) &ig7 (asic relay operation08/!/" 9 S#$CMethods of protection of Methods of protection of feederfeederNon Unit Type Protection:) Time:graded o*er:current protection%) Current:graded o*er current protection!) Distance protectionUnit Type Protection:) Differential protection%) Carrier:current protection 08/!/" 8 S#$CNon unit type protectionNon unit type protectionTime:graded protection Time:graded protection08/!/" ; S#$CCurrent graded protectionCurrent graded protection3s time graded system pro*idesdelay 'hich is not re2uired at high faulty currents+ 'e use current graded system)It cannot differentiate the s under short circuit conditionsTap:changing08/!/" S#$C %0Carrier current protectionCarrier current protection08/!/" S#$C %08/!/" S#$C %%Distance protection operates at high speed for only 80? of line Simultaneous opening of CB>s at (oth ends is not possi(le in distance protection).ence carrier current protection is used for high speed operation and simultaneous opening of (oth CB>s&ig7 Protection circuit from high *oltagesConclusion Conclusion 08/!/" S#$C %!08/!/" S#$C %/Any Queries???Any Queries??? Thank You !!!!08/!/" S#$C %"