Poeedngs of he 2006 IASM/WSAS Inenonl Confeene on neg & nvonmenl Ssems, Chlkd, Geee, M 80, 2006 (pp249253) Pm Level nd Seond Level Coodned Conol of Powe Ssems.A. ANDROULIDAIS, A.T. ALXANDRIDIS Depmen of lel nd Compue ngneeng Unves of Ps Ron 26500, Ps GRC Abs: In hs ppe, wo level oodned onol shemes fo powe ssems e dsussed. Coodnon he pm level s used o enhne nsen sbl nd o ssue volge egulon. A he seond level, he volge sepon s oeed b kng no he oun oodned onol sheme h nludes volge nd eve powe flow mesuemens he plonodes nd he elne flows of onol e espevel. ewods: olge onol, nsen sbl, oodned onol, powe ssems. Inoduon In een es, powe ssems opee unde moe sessed ondons nd lose o he sbl lms. Due o een blkous he enhnemen of powe ssem pefomne hs beome mjo onen []. In hs fme, boh he volge onol of he gd s well s he nsen sbl of he ssem s essenl n ode o mpove he powe ssem pbles. New onol shemes e poposed n ll he levels of he hehl ssem of volge nd eve powe onol. A ge enon hs been gven lso o he desgn of new dvned onolles he pm level suh s govenos nd powe ssem sblzes [2,3]. Thee mjo knds of powe ssem sbl e lel lssfed n he sho o mdem me domn. Sng fom he fse phenomenon, hese e he nsen (oo ngle) sbl, volge (eve powe) sbl nd fequen (smll sgnl) sbl. A bs sk of powe ssem opeon s o emn sble fe n smll o lge dsubne o ful. To hs end, moe sophsed onol shemes hve been poposed o ssf hs mjo equemen [3,4]. Coodned onol shemes ombned wh onvenonl o dvned onol mehods m be globl soluon [5]. In hs ppe, we popose nd dsuss wo dffeen oodned onol shemes. Fs he pm level, omplee oodned sheme s dsussed. A hs level, swhng sheme s poposed h pems n mmede on of he powe ssem sblze fe dsubne, followng b he volge egulo on when he nsen effes of he dsubne e edued. A he seond level, sml oodned onol sheme s dsussed. Pull, usng he onol e ppoh, he volge onol uses mesuemens no onl fom he plo nodes of n e bu lso fom he elnes onneng hs e o s neghbong es. Theefoe, he plo node volge mesuemen s well s he eve powe flow mesuemen nsmed b ll he elnes s needed [6]. Thus, wo ndependen level oodned onol sheme fo volge egulon s poposed o mnn nsen nd dnm sbl. 2 olge Conol of Powe Ssems The pupose of volge onol s o ompense volge devons oss he gd due o lod dsubnes. The onol of volge nd eve powe flow oss he gd beomes moe nd moe mpon due o he need of openg he gd s lose s possble o s mxmum p. A bs volge onol sheme s gven n fgue. One n see he hehl suues of he volge onol h nludes: he pm onol level (lol onolles), he seond onol level (e onolles) nd he e onol (enl uppe onolle). A he e level, he volge onol s eed n s, enlzed fshon whee ools lke opml powe flow (OPF) lgohms e used o
Poeedngs of he 2006 IASM/WSAS Inenonl Confeene on neg & nvonmenl Ssems, Chlkd, Geee, M 80, 2006 (pp249253) T e Opml Powe Flow Plo pon volge se pon onol e S e o n d Reve powe se pon PI onolle Reve powe onol loop Plo pon volge Reve powe So volge * P m o ohe onol es AR U so volge se pon von xe AR xe So volge se pon Fg.: Hehl suue of volge onol mnge he eve powe flow oss he nsmsson newok. The ole of OPF s o ssgn volge se pons o geneos n ode o keep ssem wde volge beween pespefed lms. Aodng wh hs vew, he powe ssem behves s s ssem wh que ue lod pedon. A he seond level, lge powe ssem s deomposed n numbe of onol es. In eh onol e, nsed of gheng d fom ll lod buses of he e, n lenve ppoh s used h mesues elme d fom onl smll subse of lod buses, usull one bus, lled plo node. Inuvel, he seleon of plo pons should be beween he songes ones nd he desgn e nlude shou pes nd/o sensv mx ompuons [6]. Ths mens h he bus wh he lges shou p s hezed s mn plo node. All buses wh he hghes ouplng oeffen wh he mn plo node e mked o belong o he sme onol e. Then, onol lw s mplemened, suh h ll geneos of he onol e e devoed o onol he volge of he plo node, wh onl nfomon vlble he volge plo pons. Addonll, he seond level he wellknown eve powe/volge onol loop s mplemened. Aodng o hs onol loop oeon of he sepon ous when he eve powe flow hnges. A hs level, volge onol deves onl hve ess o nfomon fom whn he onol e nd he egule he volge of he own onol e ndependenl of ohe onol e volge. As esul, he deenlzed ppoh does no depend on enl poesso nd n espond qukl o dnm phenomen h would be dfful fo opeos o hndle ohewse. Pm onol exeues he ommnds fom he uppe levels o keep geneos so volges he sepons vlues usng losedloop onols. Ths gud gns ndom dsubnes whn me sle of seonds. Ths s mplemened b he uom volge onolle (AR) nd he exe ssem of he geneo. A he pm level, sgnfn sk of he powe ssem onol s o heve, exep fom he volge egulon, he nsen sbl of he ssem. olge egulon hs level efes o he sk of exeung suessfull he ommnds fom he uppe levels n ode o mnn he volge of lod buses whn eped spefed lms dung noml opeon nd dsubed ondons. Tnsen sbl efeed o oongle sudden devons nd ddesses he poblem of loss of snhonsm of geneos when mjo dsubne ous (suh s sho u on nsmsson lne) n he me sle of few seonds. To hs end, supplemen exon deves known s powe ssem sblzes () e used [2]. In he onvenonl sheme, he
Poeedngs of he 2006 IASM/WSAS Inenonl Confeene on neg & nvonmenl Ssems, Chlkd, Geee, M 80, 2006 (pp249253) ef str A B A st mn F F S ( ) mn st W s T 2 W ω Fg. 2: The AR/ onolle whehe oo speed devon ω ppes o edue osllons nd o peven loss of snhonsm. The omplee sheme s gven n fgue 2 wheen, he AR/ onolle s pesened. Tnsen sbl nd volge egulon e desbed b dffeen models nd he ele o dffeen ses of ssem opeon, h s nsen nd posnsen opeon espevel. Alhough he bove oneps efe o dffeen openg ondons nd n he ps wee eed ndependenl, he e no muull exlusve. Fo nsne, volge devons n esul n oo ngle devons (nd pehps loss of snhonzon) nd ons o oveome nsen sbl n esul n volge osllon. Theefoe, dung nsen ondon he onvenonl AR/ sheme nno be s effen s ould be whou he smulneous on of he AR loop. 3 Coodned olge Conol he Pm Level In oodned onol sheme, we hve seen h nsen onolle nd volge egulon heve dffeen objeves. In ode fo nsen sbl nd volge egulon o be guneed, oodnon beween volge egulon (mode ) nd nsen sbl (mode 2) should be pesuded. Unde oodnon, he lol onolles pefom he noml opeons wh ognl sengs, unl n bnoml suon ppes. Then he oodnon onol kes ove o hndle he dsubne. In hs pe of oodnon swhng me s defned, when he onol lw s hnged fom mode o mode 2,.e. when we hnge ou onol objeve fom he nomnl volge vlue opeon o mngng he nsen nsbl. Swhng oodnon pnples n be oulned s follows: ) When ful ous, mode 2 s eneed o ensue he nsen sbl of he powe ssem, hen ω s bgge hn n b heshold nd swhng ous fom mode o mode 2,.e. esonble npu h ves he swhng funon n be he speed devon ω, ) A some swhng me when ω suffenl edues, he onol lw swhes fom mode 2 o mode mng dvng he volge o s peful level. A sheme desbng he bove oodned onol he pm level s gven n fgue 3. 4 Coodned olge Conol he Seond Level In he nlss of he volge onol sheme gven n fgue, we ssumed he volge onol es o be deoupled. Th s, no neons beween volge onol es (elne flows) e ken no he oun nd he mulvble ssem (he ene gd) n be vewed s n ggegon of ndependen
Poeedngs of he 2006 IASM/WSAS Inenonl Confeene on neg & nvonmenl Ssems, Chlkd, Geee, M 80, 2006 (pp249253) ef ω str S w h n g Mode Mode 2 B A mn A st S ( ) s F F Fg. 3: The pm level oodned onol sheme monovble subssems. Ths mens h he eve powe suppled b geneo n one e hs neglgble effe on he volge he buses of n neghbong e. Howeve, unde en umsnes, he bove ssumpons e no vld. I s possble h he ouplng beween heoell ndependen egons neses due o gd developmen subsequen o he pplon of seond volge onol, o nheen ouplng m exss beween onol es. Addonll, he nenl eve powe loop eh geneo s desblzng fo h n nsnl mplf nl dsubnes whh n hs se m be ul fo he ssem pefomne. In ode o ope wh suh poblems, oodned volge onol hs been poposed. The de behnd oodned volge onol s o onol elne flows beween onol es nd o esblsh fesble shemes fo mnnng volges oss he gd whn spefed lms, kng no oun vlble eve powe eouses. The deemnon of vlues fo plo nodes volge s fomuled s n opmzon poblem. The oodned level opees lge me sle hn seond volge onol nd s ul s o opmze ssem wde volge mp. Telnes eve powe mesuemens Opml Powe Flow PI Seond olge Conol Plo pon volge mesuemen * olge se pon Fg.4: The seond level oodned onol sheme wh elne eve powe mesuemen
Poeedngs of he 2006 IASM/WSAS Inenonl Confeene on neg & nvonmenl Ssems, Chlkd, Geee, M 80, 2006 (pp249253) Ths nvolves ssgnng volge se pons fo he plo nodes of seond volge onol nd hngng elne flows. Cuenl, oodned onol s no uomed, bu f wee, would opee on 5mnue bss o moe. Assumng h ll hee level of onol (pm, seond, oodned) e mel nd geogphll ndependen, we n onlude h neons beween dffeen levels of onol do no exs. In full deenlzed sheme dsn pefomne ndex s opmzed fo eh onol e o obn se pons fo he onolles. Dung opmzon fo onol e, he nfomon used fom he es of he ssem s he elne flows no he onol e. Telne flows e mesued nd used n devng opml se pons. Fgue 4 shows hs seond level oodned onol sheme. hehl volge egulon: he Iln H ssem se, 5 h In. Conf. PSCC, Lege, Seon 30, Pp. 3, 2005. [6] S. Cos, M. Pozz, C. Sbell, A. Sen, The oodned uom volge onol of he Iln nsmsson gd P I: Resons of he hoe nd ovevew of he onsolded Hehl Ssem, I Tns. on Powe Ssems, ol.9, No.4, 2004, pp. 723732. 5 Conlusons I s poposed h he pm level, powe ssems sblzes n be effevel oodned wh AR onolles o mnn nsen sbl nd volge egulon. Fuhemoe, he seond level, plonode volge mesuemens s well s elnes powe flows mesuemens n be smulneousl used n oodned sheme o heve volge egulon. Refeenes: [ ].A. Andouldks, A.T. Alexndds, H.. Psllks, D.P. Agos, ffes of powe ssem deegulon on onol desgn nd on Hgh olge gd suue nd pefomne, WSAS Tns. on C. nd Ssems, ol.4, No.9, 2005, pp. 04305. [2] H.. Psllks, A.T. Alexndds, A new exon onol fo mulmhne powe ssems I: Deenlzed nonlne dpve onol desgn nd sbl nlss, In. Jounl of Conol, Auomon & Ssems, ol.3, No.2, 2005, pp. 278287. [3] Y Guo, D. J. Hll, Y. Wng,, Globl nsen sbl nd volge egulon fo powe ssems, I Tnsons on Powe Ssems, ol 6, No 4, 200, pp. 678688. [4] J. S.. Leung, D. J. Hll, Y. N Globl powe ssem onol usng geneo exon,, FACTS deves nd po swhng, lel Powe nd neg Ssems, ol.27, 2005, pp. 448464. [5] A. Bezz, M.Melo, P. Mnnno, F. Znelln, S. Cos, M. Pozz,, Dnm pefomne of he