Worl caemy o Scence, ngneerng an ecnology Internatonal Journal o lectrcal an omputer ngneerng ol:8, No:, Incorporaton o SS BL Supplementary ontroller or ampng SSR n Power System Narenra umar, Sanjv umar Internatonal Scence Inex, lectrcal an omputer ngneerng ol:8, No:, wasetorg/publcaton/99993 bstract Statc R System (SS) s a kn o FS evce wc s use n power system prmarly or te purpose o voltage an reactve power control In ts paper presents a systematc approac or esgnng SS supplementary controller, wc s use to mprove te ampng o power system oscllaton e combne bus voltage an lne current (BL) supplementary controller as been evelope an ncorporate n te SS control system locate at te mle o te seres compensate long transmsson lne ampng o torsonal stresses ue to subsyncronous resonance resultng rom seres capactve compensaton usng BL s nvestgate n ts paper Smulaton results are carre out wt MLB/Smulnk on te I rst bencmark moel (FBM) e smulaton results sow tat te oscllatons are satsactorly ampe out by te SS supplementary controller me oman smulaton s perorme on power system an te results emonstrate te eectveness o te propose controller eywors Bus voltage an lne current (BL), seres compensaton, sub syncronous resonance (SSR), supplementary controller, egenvalue nvestgaton I INROUION RIS compensaton o long transmsson lnes s an Smportant approac to mprove te power transer capablty o power networks [] However, n suc compensate networks, te nteractons between te electrcal moes o te seres compensate network an a mecancal moe o a turbne generator sat can be le to a serous etrmental penomenon reerre to Sub-Syncronous Resonance (SSR) []-[] In recent years statc R system (SS) as been employe to an ncreasng extent n te moern power systems ue to ts capablty to work as var generaton an absorpton systems Beses, voltage control an mprovement o transmsson capablty, SS n coornaton wt supplementary controllers can be use or ampng o power system oscllatons ampng o power system oscllaton plays an mportant role not only n ncreasng te power transmsson capablty but also or stablzaton o power system contons ater crtcal aults, partcularly n weakly couple networks []-[9] e capactors n seres wt transmsson lnes may cause sub-syncronous resonance (SSR) tat can lea to turbnegenerator sat alure an electrcal nstablty at oscllaton requences lower tan te normal system requency Incentally, te sat amage can also occur ue to atgue wen te peak torques excees a lmt [], [] e propose sceme was able to amp out te torsonal moes at we range o seres compensaton However te control sceme was complex as t utlze tree erent controllers []-[] s paper ntrouces a meto or reucng te ampltues o transent torsonal torques n seres capactor compensate networks, usng supplementary controlle statc var system In ts paper a new SS control strategy or ampng torsonal oscllatons ue to subsyncronous resonance (SSR) n a seres compensate power system as been evelope e propose SS control strategy utlzes te eectveness o combne bus voltage an lne current (BL) SS supplementary controller gtal computer smulaton stuy, usng a nonlnear system moel, as been carre out to llustrate te perormance o te propose SS controller uner large sturbance It s oun tat te torsonal oscllatons are eectvely ampe out an te transent perormance o te seres compensate power system s greatly enance e I Frst Bencmark (FBM) moel s consere or te analyss o SSR [] an te complete smulaton o te power system s perorme n te MLB/Smulnk envronment e stuy s carre out base on ampng torque analyss an transent smulaton e results sow tat te suggeste controller s satsactory or ampng SSR s paper s structure as ollows Secton II escrbes te moelng o power system Secton III ntrouces te evelopment o supplementary controllers Secton I ntrouces te egenvalues an tme oman smulatons e major conclusons o te paper are gven n Secton II MOLING OF H POWR SYSM e Statc R system s bascally a sunt connecte varable R generator wose output s ajuste to excange capactve or nuctve current to te system [-8] One o te most wely use conguratons o te SS s te F- R type n wc a xe capactor (F) s connecte n parallel wt tyrstor controlle reactor (R) e stue system s base on te rst I bencmark system or subsyncronous resonance [] Narenra umar s Proessor n lectrcal ngneerng epartment at el ecnologcal Unversty (ormerly ), el, Ina (e-mal: nk_93@yaoocom) Sanjv umar s Researc Scolar n lectrcal ngneerng epartment at el ecnologcal Unversty (ormerly ), el, Ina (e-mal: actvesanjv7@remalcom) Internatonal Scolarly an Scentc Researc & Innovaton 8() 97 scolarwasetorg/37-89/99993
Worl caemy o Scence, ngneerng an ecnology Internatonal Journal o lectrcal an omputer ngneerng ol:8, No:, Internatonal Scence Inex, lectrcal an omputer ngneerng ol:8, No:, wasetorg/publcaton/99993 Fg Stuy system: I FBM [] e consere stuy system, sown n Fg conssts o one syncronous generator, two transormers &, one seres capactor an a SS n te mle o lne Generatorr Moel In te etale macne moel use n ts paper, te stator s represente by a epenent current source parallel wt te nuctance e generator moel nclues te el wnng an a amper wnng along -axs an two amper wnngs g an k along q-axs e I type- exctaton system s use or te generator [9]-[] e rotor lux lnkages ψ assocate wt erent wnngs are ene by: a a b g k 3 a a a a 7 a a b I g g were s te el exctaton voltage onstants a to a 8 an b to b are ene n [], q are an q axs components o te macne termnal current respectvely wc are ene wt respect to macne reerence rame o ave a common axs o representaton wt te network an SS, tese lux lnkages are transorme to te syncronously rotatng -Q rame o reerence usng te ollowng transormaton: I I q cos sn 8 were, Q are te respectve macne current components along an Q axs δ s te angle by wc -axs leas te -axs urrents I an I q, wc are te components o te epenent current source along an q axs respectvely, are expresse as: I = c ψ + c ψ I q = c 3 ψ g + c ψ k (3) were constantss c -c are ene n [] B Mecancal System Moelng e rotor sat system o a large turbne generator unt comprses sx turbne sectons o erent szes, can be lumpe togeter to orm a multmass moel In te mecancal moel etale sat torque ynamcs as been consere or k 3 b I b I q q b I sn cos Q () () te analyss o torsonal moes ue to SSR e mecancal system s escrbe by te sx sprng-masss moel as sown n Fg s sows te electromecancal mass-sprng amper system It conssts o xcter (enote by X), Generator (GN), Low Pressure o two stagess (LP an LPB respectvely), an ntermeate pressure stage (IP) an Hg Pressure stage (HP) turbne sectons very secton as ts own angular momentum (M) an ampng coecent (), an every two successve masses ave ter own sat stness constant () ll masses are mecancally connecte to eac oter by elastc sats [3] e ata or electrcal an mecancal system s prove n appenx e equaton o moton or sat sectons wc are connecte to eac oter s escrbe by: m m HP IP Fg Sx mass sprng mecancal system (ypcal SSR Stues) [] e M Q 3 3 " X ( I I m3 3 33 ( ) ( were M s te mecancal torque apple to eac mass an e s te electrcal torque prouce by te generator ω s rate spee (ra/s),,, 3,,,, are te angular splacements an ɷ, ɷ, ɷ 3, ɷ, ɷ, ɷ,are te angular veloctes o erent sat segments as sown n Fg xctaton System Moelng e I type- exctaton system [] s escrbe by te ollowng equatons: ( S ) Q ) LP LPB 3 r m 3 =, =,, 3,,, ( ) M ( ) M ( ) 3 M ( ) M 3 (3 33 3) 3 3 3 M3 3 ( 3 ) 3 ( 3 ) M 3 33 (3 ) M 3 ( 3) ( ) M ( ) ( ) M ( ) e 3 3 ) e GN X () Internatonal Scolarly an Scentc Researc & Innovaton 8() 97 scolarwasetorg/37-89/99993
Worl caemy o Scence, ngneerng an ecnology Internatonal Journal o lectrcal an omputer ngneerng ol:8, No:, Internatonal Scence Inex, lectrcal an omputer ngneerng ol:8, No:, wasetorg/publcaton/99993 r S F ( S ) F S () r F F S r g Network System Moelng e ac transmsson lne n ts stuy system s aapte rom te I rst SSR bencmark system [] e transmsson lne s represente by stanar lumpe parameter - crcut e network as been represente by ts axs equvalent crcut, wc s entcal wt te postve sequence network e governng equatons o te -axs, - network representaton s erve as ollows: R L L L " R L L L L () n c n n se were n = + F,L = L + L, L = L + L, L = L + L n an R = R +R a Smlarly, te equatons can be erve or te - network e - network equatons are ten transorme to -Q rame o reerence Statc R System Moelng e termnal voltage perturbaton an te SS ncremental current wegte by te actor representng current roop are e to te reerence juncton M represents te measurement tme constant, wc or smplcty s assume to be equal or bot voltage an current measurements e voltage regulator s assume to be a proportonal- ntegral (PI) controller yrstor control acton s represente by an average ea tme an a rng elay tme s B s te varaton n R susceptance F represents te ncremental supplementary controller [] e α-β axes currents enterng R rom te network are expresse as: Ls Ls R s R s were R S, L S represent R resstance an nuctances respectvely e oter equatons escrbng te SS moel are: Z = re Z + F Z ( ) M M Z RF (7) (8) I P 3 Z Z Z3 3 S s Z ΔB = (Z 3 -ΔB)/ P S re p s were Δ,Δ are ncremental magntues o SS voltage an current, respectvely, obtane by lnearzng Q, Q III LOPMN OF SS SUPPLMNRY ONROLLR e supplementary controller U s mplemente troug a rst orer supplementary controller transer uncton e state an output equatons are gven by X Y X B U X U Bus oltage Supplementary ontroller e SS bus voltage can be expresse as: Q Lnearzng (9) gves te evaton n te SS bus voltage Δ, wc s taken as te bus voltage supplementary controller: ( o / ) ( Q / ) Q () B Lne urrent Supplementary ontroller e lne current enterng to SS bus rom generator en bus s gven by = Q + Lnearzng () gves te evaton n lne current: o o Qo o were o represents operatng pont or steay state values Q F (9) () () I S SUY o emonstrate te valty o te propose sceme, I rst bencmark moel or tme oman smulaton s aopte e system conssts o two syncronous generators eac o M amountng to M equvalent syncronous generator supplyng bulk power to an nnte bus over a k, km long seres compensate sngle crcut transmsson lne e sngle crcut transmsson lne as been consere n orer to smulate te weakest system contons e system ata an torsonal sprng mass system ata are gven n appenx e SS as been consere locate at te Internatonal Scolarly an Scentc Researc & Innovaton 8() 97 scolarwasetorg/37-89/99993
Worl caemy o Scence, ngneerng an ecnology Internatonal Journal o lectrcal an omputer ngneerng ol:8, No:, Internatonal Scence Inex, lectrcal an omputer ngneerng ol:8, No:, wasetorg/publcaton/99993 mle o te transmsson lne or ts optmal perormance By conuctng te loa low stuy te ratng o te SS as been cosen to be MR nuctve to 3 MR capactve bout % seres compensaton s use at te senng en se o mpont locate SS []-[9] IM OMIN SIMULIONS FOR SSR SUY gtal computer smulaton stuy, usng a nonlnear system moel, as been carre out to emonstrate te eectveness o te propose supplementary controller uner large sturbance contons pplyng a pulse torque o 3% or s smulates a sturbance e smulaton stuy as been carre out at P G =8 MW Fgs 3-7 sow te response curves o te sat torsonal torques wt te BL SS supplementary controller e torsonal oscllatons are eectvely stablze an te propose supplementary controllers attan a sgncant mprovement n te transent perormance o te seres compensate power system (HP-IP) (pu) 8 - - 3 3 me (sec) Fg 3 araton o sat torsonal torque (HP-IP) wt BL (IP-LP) (pu) - - 3 3 me (sec) Fg araton o sat torsonal torque (IP-LP) wt BL (LP-LPB) (pu) 3 - - 3 3 me (sec) Fg araton o sat torsonal torque (LP-LPB)wt BL (LPB-GN) (pu) 3 3-3 3 me (sec) Fg araton o sat torsonal torque (LPB-GN)wt BL (GN-X) (pu) - - - - - -3 3 3 me (sec) Fg 7 araton o sat torsonal torque (GN-X)wt BL I ONLUSION In ts paper te eectveness o SS wt supplementary controller ave been evaluate or ampng te subsyncronous oscllatons n a seres compensate power system e exstence o sub syncronous contons an ter severty can be vere usng MLB as a smulaton an analytcal tool e eectveness o combne bus voltage an lne current (BL) SS supplementary controller as been evaluate or ampng te electromecancal torsonal oscllatons n a seres compensate power system e tme oman smulaton stuy emonstrates tat te Internatonal Scolarly an Scentc Researc & Innovaton 8() 977 scolarwasetorg/37-89/99993
Worl caemy o Scence, ngneerng an ecnology Internatonal Journal o lectrcal an omputer ngneerng ol:8, No:, Internatonal Scence Inex, lectrcal an omputer ngneerng ol:8, No:, wasetorg/publcaton/99993 combne bus voltage an lne current (BL) supplementary controller mprove te ampng o te torsonal electromecancal oscllatons ue to sub syncronous resonance (SSR) n te seres compensate power systeme response curves o sat torsonal torques wt te BL SS supplementary controller sow a remarkable mprovement an ter oscllatons e own eectvely PPNIX e ata or electromecancal system concernng to I FBM s gven below ll te ata are n per unt (pu) on M base Generator ata: Power ratng= M, LL = k,r a = 3, X l = pu Stablty ata: uo = s, vo = s, uo = 3 s, vo =7 s,x u = 933 pu, X v = 73 pu, X u =7 pu, X v = pu, X u = 3, X v = 3 pu, ω = 3 ra/s B I ype- xctaton System: R =, =, =, F = s, =, =, F = pu, Fmax =39, Fmn =, Rmax =73, R mn = -73 ransormer ata: R =, X = pu (Generator base) ransmsson Lne ata: oltage= k, Lengt = km, Resstance R=3 Ω / km, Reactance X=3 Ω/km, Susceptance, B c =37μ mo/km SS ata (Sx-Pulse Operaton) S ratng: Q L = Mr an Q = 3 Mr M =, S =, = 7ms, I = 9, P =, = BL I SUPPLMNRY ONROLLR PRMRS SS Supplementary ontroller B Bus oltage (B) -7 Lne urrent (L) B -3 3 39 NOWLGMN e work presente n ts paper as been perorme uner te I R& Project, nancng te power system perormance usng FS evces n te Flexble ransmsson Researc Laboratory at el ecnologcal Unversty ormerly el ollege o ngneerng, el (Ina) RFRNS [] N G Hngoran an L Gyugy, Unerstanng FS: oncepts an ecnology o Flexble ransmsson Systems, I Press, New York, [] YH Song an Jons, es, Flexble ransmsson Systems (FS), I Press, U, 999 [3] I SSR Workng Group, ountermeasures to Subsyncronous Resonance Problems, I ransactons on Power pparatus an Systems, 98,ol PS-99, No,pp8-8 [] R Payar an R arma, Statc ar System Supplementary ontroller or ampng orsonal Oscllatons, Internatonal Journal o Power an nergy Systems, Oct 99,ol, No, pp7-8 [] R Payar an R arma, "ampng orque nalyss o Statc ar System ontrollers", I ransactons on Power Systems, May 99,ol, No,pp8- [] R Payar, Facts ontrollers n Power ransmsson an strbuton, New el: New ge Publcaton, 7 [7] PM nerson, BL grawal, J an Ness, Subsyncronous Resonance n Power Systems, I Press,New York, 99 [8] I Subsyncronous Resonance Workng Group, erms entons an Symbols or Subsyncronous Oscllatons, I rans Power pparatus an Systems,98, ol, No,pp3-33 [9] I ommttee Report, Reaer s Gue to Subsyncronous Resonance,I rans on Power Systems, Feb 99,vol 7, no,pp-7 [] I orsonal Issues WG, Fourt supplement to a Bblograpy or te Stuy o Subsyncronous Resonance between Rotatng Macnes an Power Systems, I ransactons on Power Systems, ug 997,ol, No 3,pp7-8 [] R Payar, nalyss o Subsyncronous Resonance n Power System, luwer caemc Publsers, Boston, 999 [] RM Matur an R arma, yrstor-base FS ontrollers or lectrcal ransmsson Systems, I Press an Jon Wley & Sons, New York, US, Feb [3] Gorban, B Mozaar, M Ranjbar, pplcaton o subsyncronous ampng controller (SS) to SOM, lectrcal Power an nergy Systems, ec,ol3,issue,pp8- [] I Specal Stablty ontrol Workng group, Statc R ompensator Moels For Power Flow an ynamcs Perormance Smulaton, I rans Power Syst, 98, 9 (),pp 9- [] I SSR ask Force, Frst bencmark moel or computer smulaton o subsyncronous resonance, I rans on PS, Sep-Oct 977, vol PS-9,pp-7, [] N umar, evelopment o a new sceme or ampng torsonal moes n a seres compensate power system,journal o I(I),, vol 87,pp3-8 [7] Foua an u, ampng o torsonal oscllatons n power systems wt seres compensate lnes, I rans on PS,978, vol PS 97, No 3,pp7-73 [8] rs bel-ty, Seres compensaton scemes reucng te potental o sub syncronous resonance, I ransacton on Power Systems,99, vol, No,pp9- [9] Lerc, Pov, an L Xu, vance S control or ampng power system oscllaton, I rans Power Systems, 99,vol, No,pp 3 [] RS Ramsaw, R Payar, Generalze System Moel or Slp Rng Macnes, I Proc,Part,973,ol,No,pp7-8 [] R arma, Moarana, SSR n ouble-age Inucton Generator- Base Wn Farm onnecte to Seres-ompensate ransmsson Lne,I transactons on power systems, 3,ol 8, No 3,pp73-83 [] S Gupta, Narenra umar, Gupta, ampng subsyncronous resonance n power systems, I Proc on Generaton, ransmsson, an strbuton,,vol 9, No,pp79-88 [3] Narenra umar, MP ave, pplcaton o statc R system supplementary controllers to mprove te transent perormance o seres compensate long transmsson lnes, lectrc Power Systems Researc,99, 3,pp7-83 [] Punur, Power System Stablty an ontrol, McGraw Hll Inc, 99 [] Narenra umar, ampng SSR n a seres compensate power system, I Proc o Power Ina onerence, New el, [] Narenra umar, MP ave, pplcaton o supplementary controlle statc var system or ampng sub syncronous resonance n power systems, lectrc Power System Researc, 99, 37, pp89 [7] N umar, SS control strategy or ampng torsonal oscllatons ue to SSR n a seres compensate power system, I (I) Journal- L,,ol-9,pp9-7 [8] Hamma an M l-saek, pplcaton o a yrstor ontrolle R ompensator or ampng Subsyncronous Oscllatons n Power Systems,I rans on Power pparatus an Systems, Jan 98, vol PS--3, no,pp98- [9] Hamma, nalyss o power system stablty enancement by statc var compensators, I rans Power Systems,98, vol PWRS-, No,pp 7 Internatonal Scolarly an Scentc Researc & Innovaton 8() 978 scolarwasetorg/37-89/99993
Worl caemy o Scence, ngneerng an ecnology Internatonal Journal o lectrcal an omputer ngneerng ol:8, No:, Narenra umar was born n 93 lgar, (Ina) He complete BSc (lectrcal ngneerng) an MSc (Power Systems an rves) n 98 an 98 respectvely rom lgar Muslm Unversty, lgar (Ina) He obtane s P (Power Systems) rom Unversty o Roorkee n 99 He s currently workng as Proessor (lectrcal ngneerng) n el ecnologcal Unversty (ormerly el ollege o ngneerng), el (Ina) snce Jan, Hs area o Interest nclues power system operaton an control, Flexble transmsson systems, utomatc Generaton ontrol etche as publse more tan unre researc papers n te Natonal, Internatonal journals, conerence proceengs He as been aware Pt Maan Moan Malvya Memoral Prze, F nta Memoral Meal; Best paper wars, ertcates o Mert rom te Insttuton o ngneers (Ina) an Systems Socety o Ina Internatonal Scence Inex, lectrcal an omputer ngneerng ol:8, No:, wasetorg/publcaton/99993 Sanjv umar grauate n lectrcal ngneerng rom I, gra an te Mec(Power System & rves) rom MU, lgar urrently e s a Researc Scolar n lectrcal ngneerng epartment at el ecnologcal Unversty (ormerly ), elhe s autor o Book ext book o lectrcal ngneerng an co-autor o Power System nalyss He as presente many papers n varous prestgous Natonal an Internatonal conerences an journals Hs broa area o nterests nclue Power System Stablty, lectrcal Macnes an FS Internatonal Scolarly an Scentc Researc & Innovaton 8() 979 scolarwasetorg/37-89/99993