Power Flow Comparisons in a Transmission Line with UPFC and SSSCs Devices

Transcription

1 Power Flow oprisons in Trnsission Line with UPF nd SSSs Devies rkh Rjpurohit & nil Kur hudhry Deprtent of Eletril & Eletronis Engineering, MT, Mndsur, ndi E-il : rkhrjpurohit7@gilo, nilkur6352@gilo strt The devie SSSs work in the se wy s the STTOM t hs voltge soure onverter (VS) onneted in series to the trnsission line through trnsforer t required n energy soure to provide ontinuous voltge through ondenser nd to openste the losses of the VS SSS is le to exhnge tive nd retive power with the trnsission syste n this se the seril injeted voltge n dely or dvned the line urrent This ens tht the SSS n e uniforly ontrolled in ny vlue n this pper the result thus we otined y odeling trnsission syste in MTL SMULNK y using UPF nd SSSs (stti synhronous series openstor) in first se the upf is onneted to us 3 nd in seond se upf is repled y sss nd the result otined fro these two se is opred Fro these two siulink results we onlude tht the sss gives ore suitle results s opred to UPF NTRODUTON The SSS when operted with n pproprite D supply (n energy soure nd/or sink, or suitle energy storge) n injet oponent of voltge in nti-phse with the voltge developed ross the line resistne, to ountert the effet of the resistive voltge drop on the power trnsission The pility of the SSS to exhnge oth tive nd retive power kes it possile to openste for the retive nd resistive voltge drops, intining high effetive X/R rtio independently of the degree of series openstion Thus, SSS n work like ontrollle seril ondenser nd seril retne The in differene is tht the voltge infeted through SSS is not relted to the line intensity nd n e ontrolled independently This iportnt feture ens tht the SSS n e used with exellent results With low lods s well s with high lods The trnsission line with thee hving no openstion of ny kind is sid to e in stedy-stte The voltge ipressed y the effetive retne is the se with the voltge drop ross the unopensted line euse the degree of series openstions is zero The line retne is onstnt nd y dding vrile series (pitive/indutive) retne, the ount of openstion n e ontrolled n the indutive ode of opertion, the line urrent dereses s the indutive retne openstion level inreses fro 0% to 100% n the pitive ode of opertion the line urrent inreses with the pitive retne openstion level fro 0% to 33% t is worthy to note fro the digrs tht SSS not only n inrese the trnsferle power ut it n lso derese it, siply y reversing the polrity of the injeted voltge The reversed voltge is dded diretly to the line voltge drop s if the line ipedne ws inresed The effets of the opensting retne on the norlized power flow in the trnsission line re s follows: when the eulted retne is indutive, the tive nd retive power flow derese nd the effetive retne inreses s the retne openstion inreses in the negtive diretion, nd when the eulted retne is pitive the tive nd retive power flow inreses nd the effetive retne dereses s the retne openstion inreses in the positive diretion We n lso pprove of the generl use of seril ontrollle ondenser in the se of SSS it ontrols the dyni energy flow nd iproves the stility etween the ngle nd the voltge The pitive nd indutive voltge inreses the opertion field of the devie During the stility slot the potentil of dping eletroehnil osilltions inreses HRTERSTS OF SSSS: These devies SSS orret the voltge when there is fult in the network ut lso hve lot of dvntges in norl use, when there re no disturnes, like: 15

2 nterntionl Journl of dvned Eletril nd Eletronis Engineering (JEEE) Due to the ontinuous voltge injetion nd in ointion with properly strutured ontroller, it is possile to ontrol the power ftor of onneted lods; n the interonneted distriution network topologies, the dditionl voltge with its ontrollle gnitude nd phse, vn e used to work on the power flows t n lso help to over the pitive retive power dend if le networks, whih is higher thn in eril lines, inly during low lod periods tht use indissile lod elevtions; t lnes lods in interonneted distriution networks, providing lned syste; t redues the hronis used euse of the use of distriuted eletril genertion pnts t distriution network level, y tive filtering y injeting voltge with the onverter t the lod side MODELNG OF SSSS ON TRNSMSSON SYSTEM Using the onept of the ontrol syste power syste is tken to ipleent the use of SSS The two odes ie the power flow ontrol nd the voltge injetion ode re siulted in SMULNK to see the effet SSS on power syste Study is rried out to verify the utility of FT devie The figure elow illustrtes pplition study the stedy-stte nd dyni perforne of stti synhronous series openstors used to relieve power ongestion in trnsission syste The lod flow nlysis nd the single digr siultion re done on power flow siultor This softwre helps to lulte the power flow, voltge t eh us nd the ost effetiveness of the syste Fig 1: MTL SMULNK odel of the single line digr trnsission syste using SSS V EXPLNTON OF SNGLE LNE DGRM SSS is used to ontrol the power flow in 500 kv /230 kv trnsission systes The syste, onneted loop onfigurtion, onsists essentilly of five uses (1 to 5) interonneted through three trnsission lines (L1, L2, L3) nd two /230 kv trnsforer nks Tr1 nd Tr2 Two power plnts loted on the 230 kv syste generte totl of 1500 MW whih is trnsitted to, MV equivlent nd to 200 MW lod onneted t us 3 Eh plnt odel inludes speed regultor, exittion syste n norl opertion, ost of the 1200 MW genertion pity of power plnt #2 is exported to the equivlents through two 400 MV trnsforers onneted etween uses 4 nd 5 The lod flow shows tht ost of the power generted y plnt #2 is trnsitted through the 800 MV trnsforer nk 16

3 nterntionl Journl of dvned Eletril nd Eletronis Engineering (JEEE) (899 MW out of ) nd tht 96 MW is irulting in the loop Trnsforer Tr2 is therefore overloded y 99 MV This will now illustrte how SSS n relieve this power ongestion The SSS loted t the right end of line L2 is used ontrol the tive nd retive powers t the us 3, s well s the voltge t us The SSS onsist of, GTsed, onverters (one shunt onverter nd one series onverter interonneted through D us) The series onverter n injet xiu of 10% of noinl lineto-ground voltge (2887 kv) in series with line L2 95 MW 197 MW 230 kv Power Plnt #1 Pno = Tr 1: 1000 MV 230 kv/ 589 MW 690 MW 1 ypss [PQref ] [Vdqref ] L1_65 k doule iruit Trip ypss PQref UPF Vdqref UPF MW 28 Mvr 796 MW 15 Mvr V Tr 2: 800 MV 230 kv/ 587 MW -27 Mvr 1279 MW 687 MW -27 Mvr 1277 MW 4 Power Plnt #2 Pno = 1200 MW Doule lik to plot UPF ontrollle Region 2 L2_50 k _UPF MW L3_50 k 5 Equivlent MV Sope 4 Sope 5 Sope 6 Sope 7 Sope 1 Sope 2 Sope 3 Pref (pu ) -027 [PQref ] UPF Mesureents V P Q Mesureents Qref (pu ) Vdqref [Vdqref ] Vdqref Fig 2: MTL Siulink odel of ove single line digr of ove trnsission syste using UPF 95 MW 197 MW 230 kv Power Plnt #1 Pno = Tr 1: 1000 MV 230 kv/ 589 MW 690 MW 2 1 L2_50 k P O D ontroller 1 _UPF ypss L1_65 k doule iruit ypss Vqref SSS 100 -MV SSS MW 28 Mvr 796 MW 15 Mvr V Tr 2: 800 MV 230 kv/ 587 MW -27 Mvr 1279 MW 687 MW -27 Mvr 1277 MW MW L3_50 k 4 5 Power Plnt #2 Pno = 1200 MW Equivlent MV Doule lik to see SSS opertion with nd without POD SSS Vq P_2 Sope 4 Sope 5 V P Q Mesureents Sope 1 Sope 2 Sope 3 Fig 3: MTL Siulink odel of ove single line digr of ove trnsission syste using SSS 17

4 nterntionl Journl of dvned Eletril nd Eletronis Engineering (JEEE) Series injeted voltge in pu through (VSs) onneted in series to the trnsission line Through series trnsforer using UPF Note: X-xis represents the tie in seond nd Y xis represents series injeted voltge in pu Grphil result with UPF Grphil result with UPF Series injeted voltge in pu through (VSs) onneted in series to the trnsission line Through series trnsforer using SSS Grphil result with SSS Grphil result shows the oprison etween retive power flows in the trnsission line with UPF nd SSS Note:-here the Y-xis represents the retive power in MVR Grphil result with SSS Grphil results shows the oprison etween the rel power flows in the trnsission line with UPF nd SSS Note :- here Y-xis represents the rel power in MW Grphil result with UPF 18

5 nterntionl Journl of dvned Eletril nd Eletronis Engineering (JEEE) the inrese in ngle of series voltge injetion The siultion result thus we otined y introduing UPF into trnsission syste provide etter result s opred to the result otin y using SSS into the trnsission syste in se of SSS devie for little vrition in series injeted voltge the rel nd retive power strt osillting widely so in order to intin voltge gnitude phse ngle nd line ipedne of the trnsission line the use of UPF gives etter result s opred to using SSS V REFERENES Grphil result with SSS V RESULTS n the single line digr the (SSS) is onneted to us 3 nd the result thus we otin shows the oprison etween the rel nd retive power flow in the trnsission line y using UPF nd SSS to us 3 y using UPF the rel power of us 3 is inresed y 100MW ie 687MW nd retive power is -27MVR nd rein onstnt up to t=20se ut with the use of SSS for series voltge injetion fro 0980 to1025 pu the injeted voltge strt vrying t rte of 45deg/se the (SSS) tive nd retive power re set in gent loks lelled Pref(pu) nd Qref(pu) initilly the reker is losed then the power flow in us 3 is rein unffeted ut when the reker is opened the tive nd retive power strt osillting t t=2se the rel power derese y 190MW nd gin inresed up to 487MW nd rein onstnt up to t=6se t t=6se it gin inresed y 200MW nd gin dereses to 687 MW the retive power up to t=2se is -27 MVR nd t t=2se retive power inreses up to 10 MVR nd rein onstnt up to t=6se fter t=6se it gin strt deresing nd dereses up to -50 MVR nd gin inreses t t=8 se the retive power rein onstnt ie -27 MVR up to t=20 se the osilltion in retive power ws finished t t=8 se therey we find tht the use of UPF provide uh etter result s opred to the use of SSS V ONLUSONS t is neessry to intin the voltge gnitude, phse ngle nd line ipedne of the trnsission line in this pper three phse trnsission syste is siulted in MTL ones y using UPF nd gin y using SSS this pper presents the ontrol nd perforne of UPF used for power qulity iproveent the rel nd retive power inreses with [1] Vihor Gupt, Study nd effets of UPF nd its ontrol syste for power flow ontrol nd voltge injetion in power power syste, nterntionl journl of engineering siene nd tehnology vol2(7),2010, [2] Hingorni, Ng, High power Eletronis nd Flexile Trnsission Syste, EEE Power Eng REV, july 1988 [3] M Noroozin, L ngquist, M Ghndhri, G ndersson, Use of UPF for optil power flow, EEE Trnstions on Power Delivery, vol 12, No 4, Otoer 1997 [4] Phsor Model of UPF ontrol, MTL v 76, help - UPF power flow ontrol [5] ontrol lok of UPF - M Toufn, UD nnkkge, Siultion of The Unified Power Flow ontroller perforne Using PSD/EMTD, Eletril Power Syste Reserh Vol 46, 1998, pp [6] J F Keri, X Lord, Edris, Unified Power Flow ontroller (UPF): Modelling nd nlysi s, EEE Trns on Power Delivery, Vol 14, No 2, pril 1999, pp [7] L Xu nd VG gelidis, Flying pitor Multilevel PWM onverter sed UPF, EE Pro Of Eletroni Power pplition,vol 149, No 4, July 2003 Pge(s) [8] Nrin G Hingorni, Lszlo Gyugyi, Understnding FTS: onepts nd Tehnology of Flexile Trnsission Systes, EEE Press Mrketing, 1999, pp , pp [9] D Shuder, DM Hi, Edris, Opertion of the Unified Power ontroller (UPF) under prtil onstrints, EEE trnstion on Power Delivery, vol 13, No 2, pril 1998 [10] Ppi, P Zunko, D Povh, si ontrol of Unified Power Flow ontroller EEE Trns on Power Systes, Vol 12, No 4,Noveer [11] Power World Silutor v20- Glover & sr, power syste nlysis 19