The Suitable Power Control of Wind Energy Conversion System based doubly Fed Induction Generator

Transcription

1 Intenatonal Jounal of Compute Applcaton ( ) Volume 87 No.3, Febuay 4 The Sutable Powe Contol of Wnd Enegy Conveon Sytem baed doubly Fed Inducton Geneato D E. eouche Depatment of Electcal Engneeng, Faculty of cence Engneeng Taha oulay Unvety, SAIDA, Algea A. ezoua Depatment of Electcal Engneeng, Faculty of cence Engneeng Taha oulay Unvety, SAIDA, Algea. Boumeden Depatment of Electcal Engneeng, Faculty of cence Engneeng Taha oulay Unvety, SAIDA, Algea ABSTRACT The am of th pape to popoe dffeent method of contol fo a Doubly-Fed Inducton Geneato (DFIG) ued n wnd enegy conveon ytem. Th pape peent a compaatve tudy on the pefomance of thee contol method fo DFIG wnd tubne. The tudy focue on the egulaton of the actve and eactve powe exchanged between the geneato and the gd by the geneato nvete ung the contol algothm baed on vecto contol concept (tato flux oentaton), wth clacal PI contolle: popotonal ntegal. The dffeent method of contol fo the geneato ae mulated n ATAB / SIUIN and dcued. Theefoe, we conclude whch a utable contol of DFIG n Wnd Enegy Conveon Sytem. eywod Doubly fed nducton geneato, tato flux oentaton, Powe contol. INTRODUCTION Wnd enegy one of the mot pomng enewable enegy ouce due to the poge expeenced n the lat decade. Govenment ae attacted by the Wnd Enegy Conveon Sytem (WECS) wth t mple tuctue, eay mantenance and management. Wth an aveage global annual gowth ate of 4% fo the peod -6. Wnd enegy playng a majo ole n the effot to nceae the hae of enewable enegy ouce n the wold enegy mx [], [], helpng to atfy global enegy demand, offeng the bet oppotunty to unlock a new ea of envonmental potecton [3], the wold enegy ce can be olved n futue. DFIG ha ecently eceved much attenton a one of pefeed technology fo wnd powe geneaton. Compaed to a full ated convete ytem, the ue of DFIG n a wnd tubne offe many advantage, uch a educton of nvete cot, the potental to contol toque and a lght nceae n effcency of wnd enegy extacton. The wnd tubne vaable-peed opeaton ha been ued fo many eaon. Among thee ae the deceae of the tee on the mechancal tuctue, acoutc noe educton and the poblty of actve and eactve powe contol []. ot of the majo wnd tubne manufactue ae developng new lage wnd tubne n the 3 6-W ange. Thee lage wnd tubne ae all baed on vaable peed opeaton wth ptch contol ung a dectdven ynchonou geneato (wthout gea box) o a doubly fed nducton geneato (DFIG). The man advantage of the DFIG that the powe electonc equpment only cae a facton of the total powe ( 3%) [5]; th mean that the loe n the powe electonc convete, a well a the cot, ae educed. otvated by the eaon above, th pape povde a tudy of the dynamc of the gd connected wnd tubne wth DFIG. any pape have been peented, wth dffeent contol cheme of WT to extact a maxmum powe fom wnd peed vaable, baed on fuzzy contolle a t commonly done n lteatue [, and 3]. The DFIG contol cheme ae geneally baed on vecto contol concept (wth flux oentaton) wth Sldng ode Contol (SC) a popoed n [4]. SC of Actve and Reactve Powe of a DFIG and extactng maxmum powe fo Vaable Speed by WECS n [5, 6]. any wok ae done about decoupled contol of DFIG to mpove powe qualty fo WECS. In [7, 8] have tuded an advanced contol of DFIG and powe qualty mpovement. In [9] a compaon of FACTS devce lke STATCO and SVC fo the voltage tablty ue fo IG-baed wnd fam connected to a gd and load. Th pape peent a thee contol method fo the geneato nvete n ode to egulate the actve and eactve powe exchanged between the machne and the gd. Such an appoach can manage ealy the compome between dynamc pefomance and obutne o between dynamc pefomance and the geneato enegy cot. Thee compome can ealy be epected wth clacal PI contolle n DFIG contol cheme popoed n th pape. The pape oganzed a follow: ecton II peent the ente ytem model unde tudy. The thee contol tatege of DFIG and the degn of the PI contolle ae dealt, and then ae appled n ecton III. In ecton V, ome eult of mulaton, to valdate the popoed DFIG contol famewok ae peented and dcued. Secton VI conclude the pape.. ODEING OF WECS CHAIN A Fg. peent WECS, whch ue DFIG. Fom the ytem vewpont, the conveon chan can be dvded nto thee nteactng man component whch wll be epaately modeled: wnd tubne, geabox, DFIG: 35

2 Powe coeffcent Cp Intenatonal Jounal of Compute Applcaton ( ) Volume 87 No.3, Febuay 4 Geabox Geneato DFIG Convete Gd B= B=3 B=4 B=5 Tubne. Fg : Wnd enegy conveon chan.. odelng of the tubne and the geabox Wnd tubne geneaton ytem (WTGS) convet powe fom the knetc enegy of the wnd, thu t can be expeed a the knetc powe avalable n the team of a multpled by a C p facto called powe coeffcent o Betz facto. The aeodynamc powe gven by: P 3 t C p (, ) SV () Whee the a denty, R the blade length and V the wnd velocty. Contol A wnd tubne can only convet jut a cetan pecentage of the captued wnd powe. Th pecentage epeented by C p () whch functon of the wnd peed, the tubne peed and the pth angle of pecfc wnd tubne blade [5], [6]. Although th equaton eem mple, C p dependent on the ato between the tubne angula velocty t and the wnd peedv. Th ato called the tp peed ato: t R () V The typcal C p veu cuve hown n Fg.3. In a wnd tubne, thee an optmum value of tp peed ato fo whch C p maxmum and that maxme the powe fo a gven wnd peed. The peak powe fo each wnd peed occu at the pont whee C p maxmed. To maxme the geneated powe, t theefoe deable fo the geneato to have a powe chaactetc that wll follow the maxmum C p max lne [7]. A fgue howng the elaton betweenc p, and hown n Fg... Fg : Powe coeffcent vaaton agant tp peed ato and ptch angle. The tubne toque the ato of the output powe to the haft P peed t, T t ae t The tubne nomally coupled to the geneato haft though a geabox whoe gea ato G choen n ode to et the geneato haft peed wthn a deed peed ange. Neglectng the tanmon loe, the toque and haft peed of the wnd tubne, efeed to the geneato de of the geabox, ae gven by: T ae T g G m t G 5 5 (3) WheeT g the dvng toque of the geneato and m the geneato haft peed, epectvely.. odellng of the DFIG A typcal confguaton of a DFIG wnd tubne hown n Fg. It ue a wound-oto nducton geneato wth lp-ng to tanmt cuent between the convete and the oto wndng and vaable-peed opeaton obtaned by njectng a contollable voltage n to the oto at the deed lp fequency. It ued to poduce electcal powe at contant fequency whateve wnd and haft peed condton. The oto wndng fed though a vaable-fequency powe convete, typcally baed on two AC/DC IGBT-baed Voltage Souce Convete (VSC), and lnked though a DC bu. The vaable- fequency oto upply fom the convete enable the oto mechancal peed to be decoupled fom the ynchonou fequency of the electcal netwok, thee by allowng vaable-peed opeaton of the wnd tubne []. The equaton fo a DFIG ae dentcal wth a quel-cage nducton geneato except that the oto voltage ae not zeo. Ung faaday law and ohm law, the expeon elatng the voltage wth the cuent and fluxe aco the tato wndng n the PAR fame ae wtten a follow[ ]: 36

3 Intenatonal Jounal of Compute Applcaton ( ) Volume 87 No.3, Febuay 4 d d R R v d d q d dt dq R R v q d q q dt d d R vd vd d q dt ( R R ) d q dq R v q vq d q dt d ( R R ) q Whee R and phae etance. (4) R ae, epectvely, the tato and oto,, Stato and oto pe phae wndng and magnetzng nductance. the electcal peed and p the pa pole numbe. The tato and oto flux can be expeed a: d q d q Whee d d d q q d d q q, q, d quadate tato and oto cuent. p mec (5), and q ae, epectvely, the dect and The actve and eactve powe at the tato, a well a thoe povde fo gd ae defned a: P Q v v d q d d v v q d The electomagnetc toque expeed a: q q Tem p( qd d q ) (7) (6) 3. POWER CONTRO OF THE DFIG 3. Decouplng of the actve and eactve powe When the DFIG connected to an extng gd, th connecton mut be etablhed n the followng thee tep. The ft tep the ynchonzaton of the tato voltage wth the gd voltage, whch ae ued a a efeence. The econd tep the tato connecton to th gd. Afte that, the connecton can be effectvely etablhed. Once th connecton acheved, the thd tep the egulaton of the tant of the powe between the DFIG and the gd a d q efeence-fame ynchonzed wth the tato flux employed [8], []. By ettng the quadatc component of the tato flux to the null value a follow [3]: d q (9) In the pak efeence fame, appoach hown n Fg. 4. Fg 4: Flux Oentaton. Ung the condton above, uppong that the gd ytem teady, havng a ngle voltagev that lead to tato contant flux, we can ealy deduce the voltage a: v d vq V () Pe phae tato etance neglected, whch a ealtc appoxmaton fo medum powe machne ued n WECS, the tato voltage vecto conequently n quadate advance n compaon wth the tato flux vecto. By ung equaton () and (4), the oto voltage ae: v v d q O q O V d dt d R d dq R dt q q d d dt V d () WheeV the tato voltage magntude aumed to be contant and the lp ange, the oto voltage ae obtaned a follow: dd vd Rd fem d dt dq v q Rq fem q dt () Wth fem d and fem q ae the coe couplng tem between thed ax and q ax: fem d q fem q d O V d, q Fame O Stato lnked-fame Roto lnked-fame O (3) Conequently, wth egad to (9), the fluxe ae mplfed a ndcated below: O d 37

4 Intenatonal Jounal of Compute Applcaton ( ) Volume 87 No.3, Febuay 4 d d q d q (4) Theeby, th method called dect powe contol, a hown n Fg. 6. Fom (4), the cuent can be deduced a: P Q d q d d q (5) DFIG PW Ung Equaton (6), () and (5) the tato actve and eactve powe can then be expeed only veu thee oto cuent a: abc dq P Q V V q d d (6) Ung (), (6), the actve and eactve powe ae expeed a: P V Q V v q fem q p R v d fem d p R V d (7) Feld oented contol of the DFIG can then be appled wth the actve and eactve powe condeed a vaable to be contolled. Wthout takng nto account the tanfe functon of the nvete ued to feed the oto. We wll conde that th nvete dynamc vey fat; t can take a untay coeffcent. The block dagam of the ytem to be contolled peented n Fg. 5. P Q P Q v q, v P ) q Q ) q d v d, v d Fg. 6: Scheme of dect powe contol. 3.3 Indect powe contol The econd method take nto account the co couplng tem and compenate them, wth cayng out that the decoupled contol whch nclude two oto cuent loop, whch can be contolled by addng a PI egulato n each loop, whoe the efeence ae dectly deduced fom the powe efeence value, mpoed fo the machne. Thu, the oto cuent egulato contol ndectly the machne oto voltage, wthout ung a powe loop. Theeby, th method called ndect powe contol wthout powe loop, a hown n Fg. 7. d V DFIG P Q v d V p R Q PW v q q V Fg 5: Decoupled model of actve and eactve tato powe. 3. Dect powe contol To ealze an electcal poducton contol of WECS, wth cayng out a decoupled contol of the DFIG actve and eactve powe. Fo th pupoe, we hould elmnate the co couplng tem between the d-ax and q-ax by a feed fowad compenaton. Theefoe, we contol each powe ax epaately by addng a PI egulaton n the loop. Thu, the powe egulato contol dectly the machne oto voltage. p R P P Q V V q q V v q, v q q ) d d q abc dq d v d, v d q ) Fg 7: Scheme of ndect powe contol wthout powe loop 38

5 Intenatonal Jounal of Compute Applcaton ( ) Volume 87 No.3, Febuay 4 To mpove the ndect contol, we can add a egulaton loop of powe to elmnate the tatc eo whle mantanng the ytem dynamc. Theefoe, we can dtnguh the two egulaton loop fo each ax ung PI egulato, one fo contollng cuent and the othe fo powe. Theeby, th method called ndect powe contol wth powe loop, a hown n Fg. 8. V A Wth: R T T The calculated tem ae n thee table: Table. The calculated PI gan fo the tato actve powe DFIG P Q, p, P P P Q P Q ) q V V Fg 8: Scheme of ndect powe contol wth powe loop. 3.4 PI contolle ynthe The contolle tem ae calculated wth a pole-compenaton method. The tme epone of the contolled ytem wll be fxed at m, th value uffcent fo ou applcaton and a lowe value mght nvolve tanent wth mpotant ovehoot. It poble to geneate the efeence voltage fom gven efeence powe. The degn of th contolle mple. Fg. 9 how the block dagam of the ytem wth PI contolle., P Q Q P ) Q ) q V d d v q PW v q, v q q ) A p + - T. abc dq d v d, v d q ) P, Q PI contolle ( T ) / A T / A Value -9.47e-4.85 Table. The calculated PI gan fo the tato eactve powe PI contolle, p, P P ( T ) / A T / A Value -9.47e-4.85 It poble to geneate the efeence voltage fom gven efeence cuent. The degn of th contolle mple Fg. how the block dagam of the ytem wth PI contolle., d v A + p, d T. - Fg : Cuent-contol loop. In fact, the ( q q ) and ( d d ) eo ae poceed by PI contolle to gve vq and v d. Ung the aplace Tanfom, the plant can be epeented by the Cloed oop Tanfe Functon (CTF) below: A ( p ) CTF T A p A T T () Fg 9: Powe-contol loop. In fact, the ( P P ) and ( Q Q ) eo ae poceed by PI contolle to gve vq and v d. Ung the aplace Tanfom, the plant can be epeented by the Cloed oop Tanfe Functon (CTF) below: A ( p ) CTF. T A p A T T (9) A Wth: R T T Table 3. The calculated PI gan fo the dect ax PI contolle p, d, d ( T ) R T R Value

6 Intenatonal Jounal of Compute Applcaton ( ) Volume 87 No.3, Febuay 4 Table 4. The calculated PI gan fo the quadate ax PI contolle p, q, q ( T ) R T R Value The pole- compenaton n not the only method to calculate PI Contolle but t mple to elaboate wth ft-ode tanfe-functon and t uffcent n ou cae of tudy. In fact, the ( P P ) and ( Q Q ) eo ae poceed by PI contolle to gve vq and v d. Ung the aplace Tanfom, the plant can be epeented by the Cloed oop Tanfe Functon (CTF) below: Q,, P + Q Fg : Powe-contol loop. CTF () A Wth condeng.e- 4 a tme contant, () become: CTF p p V Q, P () Table 5. The calculated PI gan fo the tato actve powe, p, P P PI contolle A Value 7.33 Table 6. The calculated PI gan fo the tato eactve powe p, P, P PI contolle A Value SIUATIONS RESUT In th ecton, the wnd peed taken a contant value. Then, the maxmum powe extacton n t taken nto account; the wnd tubne dven aound ynchonou geneato peed (3 d/). Bede, the tubne and the geneato ae condeed a wokng ove deal condton (no petubaton); the paamete ae hown n the appendx. The mulaton pefomed by mpong the actve and eactve powe efeence ( P, Q ). P ange between, - 75, -5 and -5watt, Q ange between, -5 and- 5 VA. Fg., 3 peent the mulaton eult of the dect contol, ndect contol wthout powe loop. A V Wth: T and p A 4

7 Zoom of Reactve Powe (VA) Zoom of Reactve Powe (VA) Zoom of Actve Powe P(w) Zoom of Actve Powe P(w) Reactve Powe (VA) Reactve Powe (VA) Actve Powe P(w) Actve Powe P(w) Intenatonal Jounal of Compute Applcaton ( ) Volume 87 No.3, Febuay 4 x 4 x (a) (b) x 4 x (c) (d) Fg : (a) Stato actve powe of dect contol (b) Stato actve powe of ndect contol wthout powe loop (c) Stato eactve powe of dect contol (d) Stato eactve powe of ndect contol wthout powe loop P decte P P ndecte P decte P P ndecte (a) (b) Q Q Indecte -5 Q decte Q Q Indecte Q decte (c) (d) Fg 3: (a) Stato actve powe epone (b) Stato actve powe (c) Stato eactve powe epone (d) tato eactve powe epone. It can be een n Fg (a), (c) that the actve and eactve powe of the dect contol epeent a good tackng of the efeence and a vey good decouplng, except that the peence of the ocllaton dung the tanent tate. The changng of one powe doen t affect othe one. Theefoe, the contol ndependent. We notce n Fg (b), (d) that the actve and eactve powe of the ndect contol wthout powe loop epeent a good tackng and pefomance n tem of dynamc and epone. Then, the contol decoupled. Whle, n Fg 3 (a), 3 (b), 3 (c) and 3 (d) (fgue zoom epectvely) eveal a tatc eo on the actve and eactve powe whch manly due to the method of ndect contol wthout powe loop n contat to the dect contol of powe. oeove, the eo of the ndect contol wthout powe loop clealy moe mpotant on the eactve powe than on the 4

8 Zoom Actve Powe P(w) Zoom Reactve Powe (VA) Zoom Actve Powe P(w) Zoom Reactve Powe (VA) Actve Powe P(w) Reactve Powe (VA) Intenatonal Jounal of Compute Applcaton ( ) Volume 87 No.3, Febuay 4 V actve powe becaue of the coecton tem, fom the Fg 7 come to be added befoe the cuent contol loop. Accodngly, only the cuent loop contolled but the powe emaned n open loop. In ode to tet the obutne of the ndect contol wth powe loop baed on tadtonal contolle, mulaton tude wth known paamete vaaton of the oto etance and nductance. Fg. 4 peent the mulaton eult of the ndect contol wth powe loop. x 4 x (a) (b) -6 R=Rn -65 R=.Rn -7 R=;6Rn R=.8Rn R=Rn R=.Rn - R=.6Rn R=.8Rn (c) (d) =n -65 =.n -7 =.6n =.8n =n =.n =.6n =.8n (e) (f) Fg 4: (a) Stato actve powe of dect contol (b) Stato actve powe of ndect contol wthout powe loop. Fg 4 (a), 4 (b) how that the popoed contol atfe the ytem dynamc wth zeong the tatc eo. The efeence ae coectly tacked. The dynamc eact quckly and wthout exceedng. Indeed, t doen t poe a poblem fo the geneato explotaton. And then n Fg 4 (c), 4 (d), 4 (e), 4(f) the ndect powe contol wth powe loop povde dtnctly bette obutne agant the known paamete vaaton. The lat contol moe poweful than the dect contol, whch peented no dtubance n tackng, In othe wod, fo the ecuty meaue the machne; th contol able to lmt the geneato oto cuent by fxng a lmt n powe loop. 5. CONCUSION Thee contol method of DFIG wa popoed n th pape. The dect contol enue the pefomance. It ueful and peent low complexty and cot of mplementaton. Whle, the ndect contol equed a complex mplementaton, but t offe an advantage on ntegatng the oto cuent egulaton loop. Conequently, the ndect contol wth powe loop enue an electcal potecton fo machne, by ettng cuent lmtaton, whch dect contol dd not allow. Fo ntance, the utable contol of DFIG n wnd enegy conveon ytem the ndect contol wth powe loop. Indeed, we have een that dect contol the mplet, but not the mot effcent. The ndect method allow u, n combnaton wth the cloue of powe, havng a poweful and obut. It moe complex to mplement, but wll have an optmal ytem of powe geneaton by mnmzng any concen elated to change n the paamete of the geneato and the wnd ytem. 6. ACNOWEDGENTS The autho would lke to acknowledge the fnancal uppot of the Algea' nty of Hghe Educaton and Scentfc Reeach, unde CNEPRU poject: J

9 Intenatonal Jounal of Compute Applcaton ( ) Volume 87 No.3, Febuay 4 7. APPENDIX Paamete Tubne numbe of blade 3 tubne adu Gea box ato 8 DFIG Powe Nomnal voltage Fequency Numbe of pole pa 3 value 3 m 7.5W /38V (Y/D) 5 Hz Nomnal peed 955 t/m Stato etance.455ω Rotoque etance.6 Ω Stato nductance.84 H Roto nductance.8 H utual nductance.78 H (Tubne+DFIG) Geneato neta.35 g.m Fcton facto.673g.m/ Fg 5: Smulnk model of WECS. 43

10 Intenatonal Jounal of Compute Applcaton ( ) Volume 87 No.3, Febuay 4 8. REFERENCES [] V.Caldeao, V.Gald, A.Pccolo, P.Sano, A fuzzy contolle fo maxmum enegy extacton fom vaable Speed wnd powe geneaton ytem, Electc Powe Sytem Reeach, Vol.78, pp 9 8, 8. [] V. Gald, A. Pccolo, P. Sano, Explotng maxmum enegy fom vaable peed wnd powe geneaton ytem by ung an adaptve Takag Sugeno ang fuzzy model, Enegy Conveon and anagement, Vol.5, no., pp 43 4, 9. [3] Al. Eltamaly,Haan. Fah, axmum powe extacton fom wnd enegy ytem baed on fuzzy logc contol, Electc Powe Sytem Reeach, Vol.97, pp 44 5, 3. [4]. achmoum, F. Pote, Sldng mode contol of a vaable peed wnd enegy conveon ytem wth DFIG, Intenatonal Confeence and Exhbton on Ecologc Vehcle and Renewable Enege, ONACO, ach 6-9, 9. [5] B. Beltan, T. Ahmed-Al, and.e.h. Benbouzd, Sldng mode powe Contol of vaable peed wnd enegy conveon ytem, IEEE Tan. Enegy Conve., vol.3, no., pp , Jun.8. [6] Y. Bekaka, D. Ben Attou, Sldng ode Contol of Actve and Reactve Powe of a DFIG wth PPT fo Vaable Speed Wnd Enegy Conveon, Autalan Jounal of Bac and Appled Scence, Vol.5, no., pp.74-86,. [7] F. Pote, T. Bouaouche,. achmoum., Advanced contol of a doubly-fed nducton geneato fo wnd enegy conveon, Electc Powe Sytem Reeach, Vol.79, pp.85 96, 9. [8].Boutoubat,. okan,. achmoum, Contol of a wnd enegy conveon ytem equpped by a DFIG fo actve powe geneaton and powe qualty mpovement, Renewable Enegy, Vol.5, pp , 3. [9] A. Gag. R P. Sngh, Dynamc Pefomance Analy of IG baed Wnd Fam wth STATCO and SVC n ATAB / SIUIN, IJCA, Vol. 7, no. 3, pp , June 3. [] Joé u Domínguez-Gacía, Ool Gom- Bellmunt,luí Tlla-Romeoa, AdàJunyent-Feé. Indect vecto contol of a quel cage nducton geneato wnd tubne. Compute and athematc wth Applcaton 64() 4. [] Whe-n n, Chh-ng Hong, Fu-Sheng Cheng. Onlne degned hybd contolle wth adaptve obeve fovaable-peed wnd geneaton ytem. Enegy 35 () 3 e 33. [] G.Touaka, B..Nomkob, C.D.Vounaa. Effect of wnd pak wth doubly fed aynchonou geneato onmall-gnal tablty. Electc Powe Sytem Reeach 79 (9) 9. [3] Aouzellag D, Ghedam, Bekouk E. odellng of doubly fed nducton geneato wth vaable peed wnd fo netwok powe flow contol, JTEA 6, Tun. [4] T..A. Bekken, N. ohan. Contol of a doubly fed nducton wnd geneato unde unbalanced gd voltage condton. IEEE Tanacton on Enegy Conveon (ach ()) (7) [5] Zhanfeng Song, Changlang Xa, Tngna Sh. Aeng tanent epone of DFIG baed wnd tubne dung voltage dp egadng man flux atuaton and oto deep-ba effect. Appled Enegy 87 () [6] A. Gallad, P. Poue, S. Saadate,. achmoum. Vaable Speed DFIG Wnd Enegy Sytem fo Powe Geneaton and Hamonc Cuent tgaton. Renewable Enegy 34, 9 pp [7] Benoît Robyn, Buno Fanco, Phlppe Degobet, Jean Paul Haute, Vecto contol of nducton machne, Spnge-Velag ondon. [8] aue PC. Analy of electc machney. NewYok: cgaw-hll;986. IJCA T : 44