scientific paper journal

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Journal iof iScience iand iTechnology i ISSN: i2456-5660 iVolume i4, iIssue i3, iMay-June i2019, iPP i26-36 www.jst.org.in A iNew iPassive iIslanding iDetection iMethod iunder iBalanced iIslanding iCondition For iHybrid iDistributed iGeneration iSystem i A.Pandian (EEE iDepartment, iKLEF, iVaddeswaram, iGuntur iDistrict, iIndia) i Abstract i: i iTo isolve ithe ienergy iconsumption idemand iof ithe iworld iand ienvironmental iproblems iin ithe ifuture ithe idistributed igeneration iis iconsidered ian ialternative iapproach. iIn ithis ipaper ia inew ipassive iislanding idetection itechnique iwas iproposed ifor ithe iHybrid idistributed igeneration i(HDG) isystem ibased ion ichanges iin inegative isequence ivoltage i(NSV) iand icurrents iduring ian iunintentional iislanding. iIslanding iis icaused iin ithe idistributed igeneration isystem idue ito ifailures iin ithe ipower igrid. iAs iper idistribution ienergy iresources iinterconnection istandards, iit ishould ibe idetected iwithin i2 isec iwith ithe iequipments iconnected ito iit. iIt iis idifficult ito idetect iislanding iduring izero ipower iimbalance icondition. iSequence ianalyzer iwill iseparate ithe ipositive, inegative iand izero isequence icomponents iof ivoltages iand icurrents ifrom ithe ivoltages iand icurrents iobtained iat ithe ipoint iof icommon icoupling i(PCC). iDuring ia iwide irange iof ipower iimbalance iconditions ithe ichange iin inegative isequence ivoltage iand icurrents iare iexamined ifor iislanding idetection. iThe isimulation ishows ithat ithis imethod iis ifree ifrom iNon idetection izone, ieven iat izero ipower iimbalances ibetween iload iand idistribution igeneration. iThe icomputer isimulations imade iin iMatlab/ iSimulink ilaboratory ishow ithe ieffectiveness iof ithis imethod. Keywords i: iIslanding idetection, iHybrid idistributed igeneration i(HDG), iNegative isequence ivoltage i(NSV), iBalanced iIslanding, iNon idetection izone. I. Introduction i Nowadays, ithe iglobal ienergy idemand iis isupplied iby ithe icombustion iof ifossil ifuel iresources. iDue ito icontinuous icombustion iof ifossil ifuels ithe ienvironment iis iaffecting iand ifossil ifuels iare idecreasing. iSo ithe ialternate isolution ifor iglobal ienergy iconsumption idemand iand ipollution ifree icountry iis ithe iuse iof irenewable ienergy iresources ilike isolar, iwind, ietc. iDistributed igeneration iis ithe ismallest iscale ipower igeneration isource iwhich iis iconnected iat ithe iconsumer ilevel iof ipower isystem i[1]. iMost iof ithe iDG isystems iare iusing irenewable ienergy iresources iand iinterfaced ito ithe igrid iwith isuitable ipower iconverters. iDepending ion ithe inature iof ithe isource ithe ienergy imay ibe igenerated iin iAC ior iDC iforms. iThe imain iproblems iwith isuch irenewable ipower igeneration iare ian iunintentional iislanding. iDue ito ifailures iin ithe igrid, iif ithe iDG iis idisconnected ifrom ithe imain igrid, ithe iDG ialong iwith ilocal iload iforms ian iislanding i[2]. iThe iislanding iis iunsafe ito ifield ipersons iand iequipments iconnected ibecause ithe iservicing ipersons iare inot imindful ithat ithe iframe iup iis iconnected iand isupplying iwith iDG inear. iThe imain icauses iof isuch iunintentional iislanding iare idue ito ithe ifailures idetected iby ithe igrid, iaccidental iopening iof icircuit ibreakers iat ithe igrid, iintentional iopening iof iCB ifor imaintenance, ihuman ierrors iand ian iact iof inature i[3]. iThe ibasic igrid iinterfacing irules isuch ias iIEEE i1547 iand iUL i1741 ineeds ithat, iit iis inecessary ito idisconnect ithe iDG isource iwithin i2 iseconds iafter iislanding, ibecause iit ileads ito ivariations iin ithe ivoltage, ifrequency, icurrent, iTHD, iactive, ireactive ipowers ioutside ithe istandards, iwhich imay ihazardous ito icustomers iand i iloads iconnected ito iit i[4-5]. iDifferent icontrol isystems iand iinverters iare iimplemented ito iconnect iDG isources ito igrid iwith iproper isynchronization iand ito iinject ihigh iquality ipower iinto ithe igrid i[6-7]. iThe iislanding idetection imethods iare iclassified ias ilocal iislanding idetection imethods iand iremote iislanding idetection imethods. iPLCC iand iSCADA iare ithe iremote iislanding idetection itechniques; ithey idetect ithe iislanding iby igathering iinformation ifrom iDG iside iand iutility iside. iUtility iside isignals iare imonitored iby ithe iPLCC i[8-9]. iIf ithese isignals iare inot iappearing ithen iislanding iis idetected. iOn ithe iother ihand, iislanding iwas idetected iby iSCADA iwith iinformation ifrom icircuit ibreaker iauxiliary icontacts. iThe iimplementation iof ithese imethods iis ivery idifficult ibecause ithe icost iand iimplementation iof iother imonitoring idevices isuch ias itransmitters iand ireceivers iare imore i[10]. i iThe ilocal iislanding idetection imethods iare iagain iclassified ias ipassive, iactive, iand iHybrid iislanding idetection imethods i[11-12]. iBy iinjecting isome isignal iat iPCC ifor isome icycles iand iobserving ithe ideviations iin ithe ioutput isignal iactive imethods iwill idetect ithe iislanding. iIn ithe igrid iconnected isystem, ithe isystem iabsorbs ithe ilocal idisturbance iand iconsiderable ideviations iare inot iobserved. iHowever, imore ideviations iare iobserved iin ithe ioutput isignal iif ithe isystem iis iislanded i[13-17]. iBy iobserving ithese ideviations ithe iislanding iis idetected iby iactive imethods. iThe iactive imethods iare imore iefficient ithan ipassive imethods, ibut ithey ireduce ithe ipower iquality i[18- 19] iThe ilow ifrequency icurrent iinjected ithrough ithe iDQ icontroller iof iinverter ibased idistributed igeneration i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i iwww.jst.org.in i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i26 i| iPage

2. ipresented iwill iwork iinside ithe iNDZ iof ia iconventional ifrequency irelay i[20-23]. iLarge isamples iof idata icollected ifrom inon-islanding iand iislanding ievents isuch ias ivoltage, icurrent, ipower, iP.f, ietc. iand iprocessing iit iwith ithe ilearning ialgorithms, ithe iislanding iis idetected iby imachine ilearning idetection itechniques. iSome ipopular ialgorithms isuch ias iArtificial iNeural iNetworks i(ANN) i[24], iDecision iTree iModels i(DT) i[25], iand iSupport iVector iMachines i(SVM) i[26] iare iused ito idifferentiate ibetween iislanding iand inon iislanding iincidents. iIn ipassive itechniques, iregional iparameters isuch ias ivoltage, ifrequency, icurrent, iphase ijump, iactive ipower, ireactive ipower iand iother iare imonitored iat ithe iPCC, iif itheir ichanges iare ibeyond ia icertain ithreshold ilevel, ithen iislanding iis idetected i[27-32] iThe iover/ iunder ifrequency irelay iworks iwhen ithe ifrequency iis imore ior iless ithan i50.5 iand i49.5 ias iper iIndian istandards i[28]. iHybrid imethods iuse ithe icombination iof iactive iand ipassive imethods. iIf ithe iislanding iis isuspected iby ipassive imethod, ithe iactive imethod iwill iconfirm ithe iislanding. iThese imethods ihave iless iNDZ ibut ithey iare iaffected iby ipoor ipower iquality i[33-47]. iThe ipassive itechniques iare isuffering iwith ilarge iNDZ, ibut ithey iare isimple ito iimplement. iIn ithis ipaper ia inew ipassive iislanding idetection imethod iis iimplemented iwith izero iNDZ iwith ichange iin iNSV iand icurrents. iThe idifferentiated isignals iof ivoltages iand icurrents ifrom isequence ianalyzer iare icompared iwith ipredefined ivalues iand iislanding iis idetected iif ithey iare ibeyond ia ithreshold ivalue. iThis imethod iis isimple iand ifree ifrom iNDZ. iThis imethod idetects iislanding ieven iat ithe izero ipower iimbalance icondition iquickly ithan iother imethods. iThe irest iof ithe ipaper iis iorganized ias ifollows. iSystem iunder ithe istudy ialong iwith icontrol isystem iis idiscussed iin iSection iII, iThe iproposed ichange iin iNSV imethod iIII, iThe isimulated iresults, iand icomparison iwith ithe iexisting imethods iare ipresented iin isection iIV, iand iconclusions iare idrawn iin iSection iV. II. iSystem iUnder iStudy DC Bus DC/DC Converter P Inv+j Q Inv  +  P j Q CB PCC PV Array DC/AC Inverter Step up Transformer DC/DC Converter Pload+ jQ Load Grid Wind Power Local Load Battery Fig.1. iBlock idiagram iof ithe iHybrid idistributed igeneration isystem iunder istudy The itest isystem ishown iin iFigure.1 iis isimulated iwith ithe iSim-power isystems ienvironment ito ishow ithe iperformance iof ithe iproposed imethod. iThe itest isystem iis idesigned iwith iIEEE i1547 iand iUL i1741 i[4-5] iseries istandards. iThis ihybrid idistributed igeneration isystem iconsisting iof ithree idifferent isources iof isolar, iwind iand istorage ibattery. iThe iPV ipanel iis idesigned iwith isun ipower imodules i(SPR-305). iFive iseries iconnected iparallel imodules iof i66 istrings iare iconnected ito iproduce ia irated ipower iof i1kw/m2 ias ithe itemperature iis iabnormal. iThe ithevinions ivoltage iand iNorton’s icurrents iof ieach imodule iare i64.2 ivolts iand i5.96 iamperes irespectively. iThe ioutput iof ithe iPV iarray iis iconnected ito iDC/DC iboost iconverter, iwhose iduty icycle iis icontrolled iby imaximum ipower ipoint itracking i(MPPT) icontroller ito iextract imaximum ipower. iA iWind ifarm iof i9 iMW i(6*1.5 iMW) iwith iDoubly ifed iinduction igenerator iis iconsidered. iWind iturbines iusing ia iDoubly-fed iInduction igenerator i(DFIG) iconsist iof ia iwound irotor iInduction igenerator ifollowed iby ia iboost iconverter. iThe iDFIG itechnology iallows iextracting imaximum ipower ifrom ithe iwind ifor ilow iwind ispeeds iby ioptimizing ithe iturbine ispeed, iwhile iminimizing imechanical istresses ion ithe iturbine iduring igusts iof iwind. iThe ioutputs iof iboth iboost iconverters iand ibattery iare iconnected ito ithe iDC ibus. iThe iDC ivoltage ifrom iDC ibus iis isynchronized ito ithe igrid iwith isynchronous irotating ireference iframe icontroller ithrough ithree iphase iinverter, iLC ifilter iand istep iup itransformer. iThe isynchronous irotating ireference iframe icontroller ishown iin iFig.2 i[6] iwill icontrol ithe iamount iof iactive ipower idelivered ito ithe igrid, ireactive itransferring ibetween igrid iand iHybrid isystem, iDC ilink ivoltage, iand iproper i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i iwww.jst.org.in i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i27 i| iPage

3. isynchronization ito igrid iwith igood ipower iquality i[6-9]. iThe ithree iphase icircuit ibreaker i(CB) iat iPCC iis iswitched ito icreate ithe iislanding icondition. iBefore iopening iof ithe iCB ithe ihybrid iDG isystem iis iin ithe igrid iconnected imode. iBy iopening ithe iCB, ithe ihybrid iDG ialong ithe ilocal iload iforms ian iislanding icondition. iNow ithe iDG iitself isupplies ithe iload idemanded ipower iunder iworst icase iof iislanding isituation iwhich imeans izero ipower iimbalance ibetween igeneration iand iload icapacity. U Ud DC * di * DC * U dU + DC- Link Controller PI Controller PWM Inverter ++ Modulation - di Uc and -ωL Grid Ub ic ib ia qi ωL Ua - * qU + * Q Q PI  abc dq  Controller Controller ++ PLL * qi dq Uq abc Q Uq Ud Fig.2. iControl isystem iused ifor igrid iintegration iof iHybrid ienergy iresources III. Proposed iIslanding iDetection iMethod i The ihybrid ienergy isources iare iintegrated iwith ithe igrid iwith irotating ireference icontroller ishown iin iFig.2 iwill igives ibalanced ivoltages iand icurrents iat iPCC iin ithe igrid iconnected imode. iThe ibalanced ivoltages iand icurrents iat iPCC iare iequal iin imagnitude iand i1200 iapart ifrom ieach iother. iDuring iislanding ithe ivoltages iand icurrents iare iunbalanced. iThe isequence ianalyzer iwill iseparate ithe ipositive, inegative iand izero isequence icomponents ifrom iunbalanced ivoltages iand icurrents iobtained iat iPCC. iThe izero isequence icomponents ipresent ionly iwhen ithe isystem iis iassociated iwith iground. iThe inegative isequence icomponents ipresent iduring ithe iislanding ioperation. iThe ipositive isequence icomponents iwill ipresent iin iall imodes. iThe isymmetrical icomponents iof ivoltages iare iat iPCC iare idefined ias i(1)                        1 1 1   v v v v v v 0 a a 11 31   =   2 1 a b (1) 2 2 a c i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i iThe isymmetrical icomponents iof icurrents iare idefined ias                        1 1 1   i i i i i i 0 a a 11 31   =   2 1 a b (2) 2 2 a c i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i av av av ai ai and Where i , i iand i iare ithe izero isequence, ipositive isequence iand inegative isequence ivoltages. i , i 0 1 2 0 1 ai iare ithe izero isequence, ipositive isequence iand inegative isequence icurrents. iva,vb,vc iand iia, iib iand iic iare ithe ithree i 2 iphase ivoltages iand icurrents iat iPCC i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i iwww.jst.org.in i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i28 i| iPage

4. 1 120  0 cos i1200+j isin1200 or (3) i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i iα=  +  1 0 + = 2 i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i iand ialso i (4) i i i i i i i i i i i i i i i i i i i i i i iThe isequence icomponents iof ivoltages iand icurrents iare 1( 3 1( 3 1( 3 = +  +  2 ) v v v v 1 a a b c = +  +  2 ) v v v v 2 a a b c (5) = + + ) v v v v 0 a a b c i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i 1( 3 1( 3 1( 3 = +  +  2 ) i i i i 1 a a b c = +  +  2 ) i i i i 2 a a b c (6) = + + ) i i i i 0 a a b c i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i iThe ichange iin inegative isequence ivoltage iand icurrents ican ibe iwritten ias i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i iChange iin inegative isequence ivoltage iis (7) di dt 2 a i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i iChange iin inegative isequence icurrent iis i (8) by iobserving ithe irate iof ichange iof iNSV iand irate iof ichange iof iNSC ithe iislanding iis idetected. iIn ithe igrid iconnected imode ithese ideviations iare inot ipresent, ibut iin iislanding icondition ithese ichanges iare imore iand ian iislanding iis idetected. IV. The iHybrid idistribution igeneration isystem ishown iin iFig.1 iis iimplemented iusing iMATLAB i2017/ iSimulink imodel. iDifferent iislanding iand inon iislanding ievents istudied iare i1. iGrid iconnected imode i2. iIslanding imode iwith idifferent iactive ipower imismatches, iand i3. iA inon iislanding icase iof iload iswitching i iSimulation iResults iAnd iDiscussion i 4.1Grid iconnected imode The iC.B iis iclosed iin ithe igrid iconnected imode. iThe isimulated iresults iof ivoltages, icurrents, iactive ipower iand ireactive ipower iunder isteady istate ias ishown iin iFig.3. iThe iDC ilink ivoltage, ifrequency iis ishown iin iFig.4. iThe ipositive, inegative iand izero isequence ivoltages iin ithe igrid iconnected ioperation iare ishown iin iFig.5, ithe inegative isequence iand izero isequence ivoltages iare izero iand ionly ipositive isequence icomponent iis ipresent iin ithe igrid iconnected imode. i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i iwww.jst.org.in i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i29 i| iPage

5. Fig.3. iVoltages, icurrents, iActive ipower iand iReactive ipower iin igrid iconnected ioperation Fig.4. iDC ilink ivoltage iand ifrequency iin igrid iconnected ioperation Fig.5. i iPositive, inegative iand izero isequence ivoltages iin igrid iconnected ioperation i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i iwww.jst.org.in i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i30 i| iPage

6. 4.2 iNSV iand irate iof ichange iof iNSV iduring igrid iconnected, iislanding, iload iswitching iand iat idifferent iactive ipower iimbalance iconditions During ithe igrid iconnected imode ionly ithe ipositive isequence icomponent iof ivoltages iis ipresent, inegative iand izero isequence icomponents iare izero. iIn ithe iislanding icondition iand ifault iconditions inegative isequence ivoltages iare ipresent. iThe inegative isequence ivoltages iat iPCC iduring igrid iconnected iand iislanding imodes iare ishown iin iFig.6, iat it= i0.5 ithe iislanding iis iinitiated iby iopening ithe iC.B iand ishows ithat ithe ichanges iin inegative isequence ivoltages iare imore icompared ito izero iin ithe igrid iconnected imode. iThe inegative isequence ivoltage iat iPCC iwith iload iswitching iand iislanding imodes iare ishown iin iFig.7, ishows ithat ithe ioscillations iin inegative isequence ivoltages iduring iload iswitching iare inil icompared ito ithe isystem iworking iin iislanding imode. iThe irate iof ichange iof iNSV iduring igrid iconnected, iislanding, iand iload iswitching iare ishown iin iFig.8. iThe ideviations iin ithe irate iof ichange iof iNSV iduring igrid iconnected iand iload iswitching iis ivery iless iand imore iin iislanding icondition. iSo iby isetting ia ithreshold ivalue iof ithe irate iof ichange iof iNSV iat i5 ip.u/ isec, ithe iislanding iis ismoothly idetected iand itripping isignal iis iforwarded ifor ithe iprotection iof ihybrid idistributed igeneration isystem. iThe imost ipassive iislanding idetection itechniques icannot idetect iislanding iif ithe ipower iimbalance iis iless ithan i15%. iThe irate iof ichange iof iNSV iwith idifferent ipower iimbalances iis iFrom iFig.9, ithe iproposed imethod ican idetect iislanding iat ivery ilow iand izero ipower iimbalance isituations iwithin i80 ims iand ioscillations iat idifferent ipower iimbalance iconditions iare inearly isame, iand iit iis ithe imost ieffective imethod ito idetect iislanding iat izero ipower iimbalance icondition. Fig.6. iNSV iduring igrid iconnected iand iislanding imodes i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i iwww.jst.org.in i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i31 i| iPage

7. Fig.7. iNSV iduring iLad iswitching iand iislanding imodes Fig.8. iRate iof ichange iof iNSV iDuring igrid iconnected, iislanding iand iload iswitching icondition Fig.9. iRate iof ichange iof iNSV iat idifferent iactive ipower iimbalances 4.3 iNSC iand irate iof ichange iof iNSC iduring igrid iconnected, iislanding, iload iswitching iand iat idifferent iactive ipower iimbalance iconditions In ithe iislanding icondition iand ifault iconditions inegative isequence icurrents iare ipresent iwhile iin ithe igrid iconnected imode ithey iare inot iavailable. iThe inegative isequence icurrents iat iPCC iduring igrid iconnected iand iislanding imodes iare ishown iin iFig.10, iat it= i0.5 ithe iislanding iis iinitiated iby iopening ithe iC.B iand ishows ithat ithe ichanges iin inegative isequence icurrents iare imore icompared ito izero iin ithe igrid iconnected imode. iThe inegative isequence icurrents iat iPCC iduring iload iswitching iand iislanding imodes iare ishown iin iFig.11, ishows ithat ithe ioscillations iin inegative isequence icurrents iduring iload iswitching iare inil icompared ito ithe isystem iworking iin iislanding imode. iThe irate iof ichange iof iNSC iduring igrid iconnected, iislanding, iand iload iswitching iare ishown iin iFig.12, iThe ideviations iin ithe irate iof ichange iof iNSC iduring igrid iconnected iand iload iswitching iis ivery iless iand imore iin iislanding icondition. iSo iby isetting ia ithreshold ivalue iof ithe irate iof ichange iof iNSC iat i10 ip.u/ isec, ithe iislanding iis ismoothly idetected iand itripping isignal iis iforwarded. iThe irate iof ichange iof iNSC iwith idifferent ipower iimbalances iis ifrom iFig.13, ithe iproposed imethod ican idetect iislanding iat ivery ilow iand izero ipower i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i iwww.jst.org.in i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i32 i| iPage

8. iimbalance isituations ialso iwithin i80 ims iand ioscillations iat idifferent ipower iimbalance iconditions iare inearly isame, iand iit iis ithe imost ieffective imethod ito idetect iislanding iat izero ipower iimbalance icondition Fig.10. i iNSC iduring igrid iconnected iand iislanding imodes Fig.11. iNSC iduring iLoad iswitching iand iislanding imodes i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i iwww.jst.org.in i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i33 i| iPage

9. Fig.12. iRate iof ichange iof iNSC iDuring igrid iconnected, iislanding iand iload iswitching icondition Fig.13. iRate iof ichange iof iNSC iat idifferent iactive ipower iimbalances 4.4Comparison iwith iexisting ipassive imethods Table: i1. iComparison iof iexisting ipassive iislanding idetection imethods Passive iIslanding idetection imethod NDZ Detection iTime Large iwith ia ilarge ivalue iof iQ Voltage iand icurrent iharmonic idetection 200 ito i300 ims Over iunder ivoltage/ iover iunder ifrequency iOUV/ iOUF Large i 400 ims ito i2s Rate iof ichange iof ifrequency i(ROCOF) Small 300ms Rate iof ichange iof ifrequency iover ipower i(ROCOP) Smaller ithan iROCOF 250ms Rate iof ichange iof ipower i(ROCOP) Smaller ithan iOUV/OUF 400ms Phase iJump iDetection i(PJD) Large 100-200 ims Voltage iUnbalance i(VU) Large 100 ims In ithis ipart iof ithe ipaper ithe iexisting ipassive iislanding idetection imethods iare icompared iwith ithe iproposed imethods. iAlmost iall ipassive iislanding idetection imethods ifail ito idetect iislanding iduring izero ipower iimbalance iconditions iand ithe iNDZ iis ilarge isome iof iwhich iare ishown iin itable.1. i iThe iproposed imethod ican idetect iislanding iwithin i80 ims ieven iat izero ipower iimbalance iconditions iand ithis imethod iis icompletely ifree ifrom ithe iNDZ. i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i iwww.jst.org.in i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i34 i| iPage

10. V. Conclusion i i i i i i i i i i i i iTo iovercome ithe iproblems iwith iunintentional iislanding, ia inew ipassive iislanding idetection imethod iis ipresented iin ithis ipaper iwith irate iof ichange iof iNCS iand irate iof ichange iof iNSV. iMost iof ithe ipassive iislanding idetection imethods ifail ito idetect iislanding iat izero ipower iimbalance icondition. iThis imethod iis iworking iefficiently iduring izero ipower iimbalance icondition iwhich iis ithe iworst icase iof iislanding iand idetecting iislanding iwithin i80 ims. ithis imethod iis ifree ifrom iNDZ. i iThis imethod iclearly idifferentiating ibetween iislanding iand inon iislanding ievents. References i [1] Ashok iBindra i“A iUnified iInterface ifor iIntegrating iRenewable iEnergy iSources iwith ithe iSmart iGrid”, iIEEE iPower iElectronics iMagazine, ivol. i3, ino. i4, ipp: i4 i– i6, i2016. [2] Yu iZheng; iZhao iYang iDong; iKe iMeng; iHongming iYang; iMingyong iLai; iKit iPo iWong i“Multi-objective idistributed iwind igeneration iplanning iin ian iunbalanced idistribution isystem” iCSEE iJournal iof iPower iand iEnergy iSystems,Volume: i3, iIssue: i2,Pages: i186 i– i195, iYear: i2017. [3] Karan iSareen, iBhavesh iR. iBhalja i, iRudra iPrakash iMaheshwari i“Universal iislanding idetection itechnique ibased ion irate iof ichange iof isequence icomponents iof icurrents ifor idistributed igenerations” iIET iRenew. iPower iGener., ipp. i1–10, i2015. [4] Thomas iBasso; iSudipta iChakraborty; iAndy iHoke; iMichael iCoddington i“IEEE i1547 iStandards iadvancing igrid imodernization” iIEEE i42nd iPhotovoltaic iSpecialist iConference i(PVSC), iPages: i1 i– i5, iYear: i2015 [5] “UL1741 istandard ifor isafety ifor istatic iconverters iand icharge icontrollers ifor iuse iin iphotovoltaic ipower isystems,” iUnderwriters iLaboratories, iJan i2001. [6] Yash iP. iBhattl iand iMihir iC. iShah i“Design, iAnalysis iand iSimulation iof iSynchronous iReference iFrame ibased iPhase iLock iLoop ifor iGrid iConnected iInverter”, iIEEE iInternational iConference ion iPower iElectronics iIntelligent iControl iand iEnergy iSystems i(ICPEICES-2016), ipp. i1-5 i, i2016. [7] Joydip iJana, iHiranmay iSaha, iKonika iDas iBhattacharya i“a ireview iof iinverter itopologies ifor isingle iphase igrid iconnected iphotovoltaic isystems”, iRenewable iand iSustainable iEnergy ireviews, ivol. i72, ipp.1256-1270, i2017. [8] Giovanni iArtale; iAntonio iCataliotti; iValentina iCosentino; iDario iDi iCara; iSalvatore iGuaiana; iSalvatore iNuccio; iNicola iPanzavecchia; iGiovanni iTinè i“Smart iInterface iDevices ifor iDistributed iGeneration iin iSmart iGrids: iThe iCase iof iIslanding” iIEEE iSensors iJournal, iVolume: i17, iIssue: i23, iPages: i7803 i– i7811, i2017. [9] GökayBayrak in, iErsanKabalci i“Implementation iof ia inew iremote iislanding idetection imethod ifor iwind–solar ihybrid ipower iplants” iRenewable iand iSustainable iEnergy iReviews i58,pp.1–15, i2016. [10] Subhra iJ. iSarkar; iPalash iK. iKundu i“A iproposed imethod iof iload ischeduling iand igeneration icontrol iusing iGSM iand iPLCC itechnology” iMichael iFaraday iIET iInternational iSummit, ipp: i273 i- i277, i2015. i [11] Jimmy iY. iZhang; iCameron iM. iBush i“PMU ibased iislanding idetection ito iimprove isystem ioperation” iIEEE iPower iand iEnergy iSociety iGeneral iMeeting i(PESGM), ipp. i1 i– i5, i2016. i i [12] Hua iHan; iXiaochao iHou; iJian iYang; iJifa iWu; iMei iSu; iJosep iM. iGuerrero i“Review iof iPower iSharing iControl iStrategies ifor iIslanding iOperation iof iAC iMicrogrids” iIEEE iTransactions ion iSmart iGrid, iVolume: i7, iIssue: i1, iPages: i200 i– i215, i2016. [13] P. iGupta, iR. iBhatia, iand iD. iJain, i“Average iabsolute ifrequency ideviation ivalue ibased iactive iislanding idetection itechnique,” iIEEE iTransactions ion iSmart iGrid, ivol. i6, ino. i1, ipp. i26–35, iJan i2015 [14] Ke iJia, iHongsheng iWei, iTianshu iBi, iDavid iThomas iand iMark iSumner i“An iIslanding iDetection iMethod ifor iMulti-DG iSystems iBased ion iHigh iFrequency iImpedance iEstimation” iIEEE iTransactions ion isustainable ienergy, iVolume: i8, ino. i7 ipp: i74 i– i83, i2017. [15] iSuman iMurugesan; iVenkatakirthiga iMurali; iS. iArul iDaniel i“Hybrid iAnalyzing iTechnique ifor iActive iIslanding iDetection iBased ion id-Axis iCurrent iInjection” i iIEEE iSystems iJournal, ivol. ipp, ino. i99, ipp. i1-10, i2017. [16] iZhongwei iGuo i“A iharmonic icurrent iinjection icontrol ischeme ifor iactive iislanding idetection iof igrid-connected iinverters” iIEEE iInternational iTelecommunications iEnergy iConference i(INTELEC), ipp: i1 i- i5, i i2015. [17] Snehamoy iDhar, iSheetal iChandak; iM iH iNaeem i“Harmonic iprofile iinjection ibased i iactive iislanding idetection ifor iPV-VSC ibased igrid”, i iIEEE iPower iCommunication iand iInformation iTechnology iConference i(PCITC),Pages: i489 i- i496, i2015. i [18] Aref iPouryekta; iVigna iK. iRamachandaramurthy; iJeyraj iSelvaraj i“Active iislanding idetection ifor isynchronous igenerators iusing ispeed idisturbance iinjection itechnique” iIEEE iConference ion iClean iEnergy iand iTechnology i(CEAT), ipp: i54 i- i59 i,2013. [19] Tai-Zhou iBei i“Erratum: iAccurate iactive iislanding idetection imethod ifor igrid-tied iinverters iin idistributed igeneration” iIET iRenewable iPower iGeneration, iVolume: i11, iIssue: i13, iPages: i1731 i– i1731, i2017. [20] Pankaj iGupta; iRavinder iSingh iBhatia; iDinesh iKumar iJain i“Islanding idetection iof iactive idistribution isystem iwith iparallel iinverters” iIEEE iInternational iConference ion iSignal iProcessing, iInformatics, iCommunication iand iEnergy iSystems i(SPICES), iPages: i1 i– i5, i2017. [21] Ahmed iM. iI. iMohamed; iYasser iA-R. iI. iMohamed i“Analysis iand iMitigation iof iInteraction iDynamics iin iActive iDC iDistribution iSystems iwith iPositive iFeedback iIslanding iDetection iSchemes” iIEEE iTransactions ion iPower iElectronics, iVolume: iPP, iIssue: i99, iPages: i1 i– i10, i2017. [22] Pankaj iGupta; iR. iS. iBhatia; iD. iK. iJain i“Active iROCOF iRelay ifor iIslanding iDetection” iIEEE iTransactions ion iPower iDelivery, iVolume: i32, iIssue: i1,Pages: i420 i– i429, i2017. i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i iwww.jst.org.in i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i35 i| iPage

11. [23] Ali iEmadi; iHosein iAfrakhte; iJavad iSadeh i“Fast iactive iislanding idetection imethod ibased ion isecond iharmonic idrifting ifor iinverter- based idistributed igeneration” iIET iGeneration, iTransmission i& iDistribution, iVolume: i10, iIssue: i14,Pages: i3470 i– i3480, i2016. [24] S. iSalman, iD. iKing, iand iG. iWeller, i“Investigation iinto ithe idevelopment iof ia inew iANN-based irelay ifor idetecting iloss iof imains iof iembedded igeneration,” iin iIEEE iInternational iConference ion iDevelopments iin iPower iSystem iProtection, ivol. i2, ipp. i579–582 iVol.2, iApril i2004. [25] O. iFaqhruldin, iE. iEl-Saadany, iand iH. iZeineldin, i“A iuniversal iislanding idetection itechnique ifor idistributed igeneration iusing ipattern irecognition”, iIEEE iTransactions ion iSmart iGrid, ivol. i5, ino. i4, ipp. i1985–1992, iJuly i2015. [26] B. iMatic-Cuka iand iM. iKezunovic, i“Islanding idetection ifor iinverter ibased idistributed igeneration iusing isupport ivector imachine imethod”, iIEEE iTransactions ion iSmart iGrid, ivol. i5, ino. i6, ipp. i2676–2686, iNov i2014. [27] Abhilasha iKumari; iRupendra iKumar iPachauri; iYogesh iK. iChauhan i“Passive iislanding idetection iapproach ifor iinverter ibased iDG iusing iharmonics ianalysis” iIEEE i1st iInternational iConference ion iPower iElectronics, iIntelligent iControl iand iEnergy iSystems i(ICPEICES), iPages: i1 i– i6, i2016. [28] Manop iYingram; iSuttichai iPremrudeepreechacharn i“Investigation iover/under-voltage iprotection iof ipassive iislanding idetection imethod iof idistributed igenerations iin ielectrical idistribution isystems” iInternational iConference ion iRenewable iEnergy iResearch iand iApplications i(ICRERA), iPages: i1 i– i5, i2012 [29] Bikiran iGuha; iRami iJ. iHaddad; iYouakim iKalaani i“A inovel ipassive iislanding idetection itechnique ifor iconverter-based idistributed igeneration isystems” iIEEE iPower i& iEnergy iSociety iInnovative iSmart iGrid iTechnologies iConference i(ISGT), iPages: i1 i– i5, i2015. [30] Akbar iDanandeh; iHeresh iSeyedi; iEbrahim iBabaei i“Islanding iDetection iUsing iCombined iAlgorithm iBased ion iRate iof iChange iof iReactive iPower iand iCurrent iTHD iTechniques” iAsia-Pacific iPower iand iEnergy iEngineering iConference, iPages: i1 i– i4, i2012. [31] H. iNasir iaghdam; iN. iGhadimi; iP. iFarhadi; iF. iHashemi; iR. iGhadimi i“Detecting ithe ianti-islanding iprotection ibased ion icombined ichanges iof iactive iand ireactive ioutput ipowers iof idistributed igenerations” i3rd iInternational iConference ion iComputer iResearch iand iDevelopment, iVolume: i3, iPages: i285 i– i289, i2011. [32] Vivek iMenon; iM. iHashem iNehrir i“A iHybrid iIslanding iDetection iTechnique iUsing iVoltage iUnbalance iand iFrequency iSet iPoint” iIEEE iTransactions ion iPower iSystems, iVolume: i22, iIssue: i1, iPages: i442 i– i448, i2007. [33] Haidar iSamet; iFarid iHashemi; iTeymoor iGhanbari i“Islanding idetection imethod ifor iinverter-based idistributed igeneration iwith inegligible inon-detection izone iusing ienergy iof irate iof ichange iof ivoltagephase iangle” iIET iGeneration, iTransmission i& iDistribution, iVolume: i9, iIssue: i15, iPages: i2337 i– i2350, i2015. [34] Pukar iMahat; iZhe iChen; iBirgitte iBak-Jensen i“A iHybrid iIslanding iDetection iTechnique iUsing iAverage iRate iof iVoltage iChange iand iReal iPower iShift” iIEEE iTransactions ion iPower iDelivery, iVolume: i24, iIssue: i2, iPages: i764 i– i771, i2009. [35] Farhad iNamdari; iMahsa iParvizi; iEsmaeel iRokrok i“A inew ihybrid iislanding idetection imethod icombination iof iNJSMS iand iQ-f ifor iislanding idetection iof imicrogrids” iThe i9th iPower iSystems iProtection iand iControl iConference i(PSPC2015), iPages: i6 i– i11, i2015. [36] Shahrokh iAkhlaghi; iAli iAsghar iGhadimi; iArash iAkhlaghi i“A inovel ihybrid iislanding idetection imethod icombination iof iSMS iand iQ- f ifor iislanding idetection iof iinverter- ibased iDG” iPower iand iEnergy iConference iat iIllinois i(PECI), iPages: i1 i– i8, i2014. [37] Mahdiyeh iKhodaparastan; iHesan iVahedi; iFarid iKhazaeli; iHashem iOraee i“A iNovel iHybrid iIslanding iDetection iMethod ifor iInverter-Based iDGs iUsing iSFS iand iROCOF”IEEE iTransactions ion iPower iDelivery, iVolume: i32, iIssue: i5, iPages: i2162 i– i2170, i2017. iFatemeh iGhalavand; iHossien iKazemi iKaregar i“New ihybrid iislanding idetection iin iDC ilink ifor ihybrid inetworks” iIranian iConference ion iElectrical iEngineering i(ICEE), iPages: i1107 i– i1113, i2017. [39]CR iReddy, iKH iReddy, i"ISLANDING iDETECTION iMETHOD iFOR iINVERTER iBASED iDISTRIBUTEDGENERATION iBASED iON iCOMBINED iCHANGES iOF iROCOAP iAND iROCORP", iVol. i117, ipp. i433-440, iDec. i2017. [40] iB iV iRajanna i, iCh iRami iReddy, iK iHarinadha iReddy, i"Design, iModeling i& iSimulation iof iDSTATCOM ifor iDistribution iLines ifor iPower iQuality iImprovement", iVol. i17, ipp. i1-10, iApr. i2017. [41] iCh iRami iReddy, iK iHarinadha iReddy," iIslanding iDetection iusing iDQ iTransformation ibased iPI iApproach iin iIntegrated iDistributed iGeneration", iVol. i10, ipp. i679-690, iFeb. i2017. [42] iB iV iRajanna, iK iS iSrikanth," iGrid iConnected iInverter ifor iCurrent iControl iby iUsing iAnti-Islanding iTechnique", iVol. i9, ipp. i926- 932, iJune. i2018. [43] iS iGuru iPrasad, iKS iSrikanth, iB iV iRajanna," iAdvanced iActive iPower iFilter iPerformance ifor iGrid i i iIntegrated iHybrid iRenewable iPower iGeneration iSystems", iVol. i11, ipp. i60-73, iJuly. i2018. [44] iB iV iRajanna, iSVNL iLalitha, iGanta iJoga iRao, iSK iShrivastava, i"Solar iPhotovoltaic iGenerators iwith iMPPT iand iBattery iStorage iin iMicrogrids", iVol. i7, ipp. i701-712, iSep. i2016. [45] iB iV iRajanna, iSVNL iLalitha, iGanta iJoga iRao, iSK iShrivastava, i" iBPSK iModulation iand iDemodulation iwith iPower iLine iCarrier iCommunication iand iGSM iCommunication ifor iSmart iMetering", i i i i i i i i i i i i i i i i i iVol. i7, ipp. i713--722, iSep. i2016. [46] iB iV iRajanna, iGanta iJoga iRao, iSK iShrivastava, i" iDefining iControl iStrategies ifor iMicro iGrids iIslanded iOperation iwith iMaximum iPower iPoint iTracking iusing ia iFuzzy iLogic iControl iScheme", i i i i i i i i i i i i i i i i i i i iVol. i7, ipp. i723--733, iSep. i2016. [47] iB iV iRajanna, iO iChandra iSekhar, iM iKiran iKumar, i" iAutomatic iMeter iReading iFor iSmart iMetering iBy iUsing iQPSK iModem iWith iPLC iChannel iand iGSM iModem.", iVol. i15, ipp. i1--10, iMay. i2015. i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i iwww.jst.org.in i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i36 i| iPage