SPEED-SENSORLESS CONTROL STRATEGY FOR MULTI-PHASE INDUCTION GENERATOR IN WIND ENERGY CONVERSION SYSTEMS

Transcription

1 Dumni}, B. P., et al.: Speed-Senole Contol Stategy fo Multi-Phae... THERMA SCIENCE: Yea 6, Vol., Suppl., pp. S48-S493 S48 Intoduction SPEED-SENSORESS CONTRO STRATEGY FOR MUTI-PHASE INDUCTION GENERATOR IN WIND ENERGY CONVERSION SYSTEMS by Boi P. DUMNI] *, Dagan M. MII]EVI], Bane P. POPADI], Vladimi A. KATI], and Zoltan J. ^ORBA Faculty of Technical Science, Univeity of Novi Sad, Novi Sad, Sebia Oiginal cientific pape DOI:.98/TSCI593D Renewable enegy ouce, epecially wind enegy conveion ytem (WECS), exhibit contant gowth. Inceae in powe and intalled capacity ha led to advance in WECS topologie. Multi-phae appoach peent a new development diection with eveal key advantage ove thee-phae ytem. Paied with a enole contol tategy, multi-phae machine ae expected to take pimacy ove tandad olution. Thi pape peent peed enole vecto contol of an aymmetical ix-phae induction geneato baed on a model efeence adaptive ytem. Suggeted topology and developed contol algoithm how that enole contol can yield appopiate dynamic chaacteitic fo the ue in WECS with inceae in eliability and obutne. Key wod: wind enegy, multi-phae machine, vecto contol, peed etimation Recently, elevant epot how that cumulative powe of intalled wind enegy conveion ytem (WECS) woldwide wa ove 36 GW at the end of 4 []. The annual gowth in capacity, duing the yea 4, wa an atonihing 44%, with the ecod beaking annual intalled capacity ove 5 GW. Mot dominant inceae wa exhibited by China with 3 GW, o 45% of wold annual maket. Futue of wind enegy maket look bight, with foecat howing the tend of tabilization afte 5 and expected annual maket gowth at 4-6% befoe 9. The tend would et the cumulative capacity gowth between % and 5%, potentially ending 9 at global cumulative intalled capacity jut about 65 GW, a een in fig. []. High penetation of enewable enegy ouce, epecially WECS, ha led to the intoduction of new technologie and olution in ode to deal with known deficiencie of taditional ytem [, 3]. Cuently deployed WECS topologie have achieved thei limit, epecially with epect to thei powe ating. Motly bound by the advance in powe electonic convete, thee ae eveal appoache in ovecoming thee containt [4, 5]. Two majo diection in futhe development of WECS ae: multi-winding (multi-phae) geneato with ditibuted convete and multiple geneato with ditibuted geabox. Clea diadvantage of the latte topology lie in the complex geabox ytem, which can ignificantly inceae the * Coeponding autho; dumnic@un.ac.

2 S48 Dumni}, B. P., et al.: Speed-Senole Contol Stategy fo Multi-Phae... THERMA SCIENCE: Yea 6, Vol., Suppl., pp. S48-S493 pice, and maintenance cot of the ytem. Futhemoe, complex geabox ytem can lead to evee deceae in WECS eliability. Figue. Wind enegy maket tatitic 4-9 (ouce GWEC) On the othe hand, uing multi-phae geneato in WECS offe eveal advantage in addition to inceaing the powe ating of the ytem. In the midt of multiphae machine type one concept claimed it place a one of the mot inteeting and mot invetigated. Thoe ae aymmetical ix-phae (dual thee-phae) induction machine that have two theephae winding et with patial hift of 3 electical degee [6, 7]. Multi-phae dive, with ix-phae induction machine, ae featued in highly eliable application, making them a pefect fit in wind enegy application. With the tandad benefit that induction machine offe, intoduction of multiple phae allow the dive to become pominently immune to failue. Unlike thei thee-phae countepat, ix-phae machine in WECS can opeate unde faulty condition by a imple eduction to a ytem with lowe phae numbe. A a eult, the obutne and eliability of the dive i geatly inceaed [8]. Howeve, mathematical model of the ix-phae machine opeating with at leat one phae fault i diffeent fom mathematical model of a machine opeating in a egime without fault. The complete analyi and modelling of a ix-phae machine unde phae fault i peented in [9]. Thi change in mathematical model inevitably lead to the change in contol algoithm, modulation technique and peed etimation algoithm. iteatue popoe eveal diffeent technique fo ix-phae machine opeation unde faulty condition. One olution ecommend diconnection of a thee-phae winding containing the faulty phae [, ]. The econd olution popoe the eduction of the machine phae numbe to include all healthy phae, with the poibility of achieving the ated machine toque [], while the thid common olution popoe the tato cuent limitation at ated value, in addition to the phae numbe eduction. Since the change in mathematical model i ignificant and implie the change in contol algoithm and all etimato, thi analyi exceed the intended cope of thi pape and will not be futhe dicued. Compaed to the thee-phae olution, ix-phae machine offe a vaiety of contol option, egading opeating egime with wind powe lowe than nominal, with the poibility of maintenance cot eduction by applying uitable optimization and electing appopiate numbe of phae fo powe tanfe. Moeove, uing ix-phae machine in WECS will leen the mechanical te of the ytem component ince they have ignificantly lowe toque ipple [6]. With the inceae in efficiency, by pope contol of the machine ide con-

3 Dumni}, B. P., et al.: Speed-Senole Contol Stategy fo Multi-Phae... THERMA SCIENCE: Yea 6, Vol., Suppl., pp. S48-S493 S483 vete, the WECS baed on a ix-phae induction machine make fo a obut, elatively inexpenive and highly eliable olution. Conideing main advantage of uch a dive, the extenion of the field oiented contol (FOC) pinciple fom thee-phae to ix-phae machine offe well-known, obut and computationally non-demanding algoithm [3]. Howeve, pope implementation of the vecto contol algoithm equie accuate oto peed ignal, in ode to povide the decoupling between machine toque and flux. Moe often, acquiing uch ignal can have negative impact on the ytem obutne and eliability. Thi i paticulaly emphaized by the hah envionmental and WECS opeating condition. Reliability of the WECS can, theefoe, be impoved by eliminating the peed eno, whilt educing maintenance cot. Elimination of the peed eno i poible with the ue of ix-phae induction geneato tate and output etimation algoithm. Model efeence adaptive ytem (MRAS) peed etimation algoithm povide imple and eliable technique, with dynamic pefomance imila to thoe of tandad dive that include peed meauement [4]. The intoduction of peed etimation technique baed on MRAS algoithm to the ix-phae induction machine dive will geatly complement poitive featue of the oveall ytem. Futhemoe, known MRAS inufficiencie can be upaed by the ame impovement etablihed fo tandad thee-phae induction machine dive [5, 6]. Thi pape will peent the peed enole vecto contol of an aymmetical ixphae induction machine. Speed etimation technique i baed on a MRAS algoithm adjuted fo the ue in aymmetical ix-phae induction machine. Simulation eult will how that the peed etimation method i capable of tacking the otational peed of the machine unde ealitic condition. Popoed technique i computationally vey efficient and eay to implement, which in addition to it obutne make it uitable fo implementation in WECS. Oveview of the ytem topology and contol tategy Aymmetical ix-phae induction geneato with full-capacity convete With the contant eduction in pice of emiconducto, and contant advance in technology, maket i opened fo new eliable convete topologie to be ued in WECS. Alongide the advance in powe electonic, and in egad to the powe limitation of the cuent WECS topologie, olution with diffeent electical machine can be offeed now. The benefit offeed by multi-phae machine can imply be tanfeed to WECS, when it i poible to adequately implement the contol uing multi-phae convete [7]. A WECS topology diectly deived fom it thee-phae countepat i the topology with aymmetical ix-phae induction geneato with full-capacity convete, hown in fig.. Thi topology conit of ix-phae quiel cage induction geneato (SCIG) and back to back two-level voltage ouce convete (VSC), with a ix-phae machine ide and a thee-phae gid ide convete. Both VSC ue inulated-gate bipola tanito (IGBT) a baic witching component; they have tandad bidge topology and ae coupled uing the DC-link. Uing thi topology enable upaing powe limitation of tandad WECS topologie, while the powe limitation of the convete i upaed with paallelizing eveal thee-phae VSC channel [3]. To implement maximum powe point tacking (MPPT) algoithm, the geneato ide convete (voltage ouce ectifie VSR) i ued to contol machine peed and/o toque. Powe tanfe i completed with gid ide convete (voltage ouce invete VSI), contolling the DC-link voltage and injected active and/o eactive powe. Thi allow fo

4 S484 Dumni}, B. P., et al.: Speed-Senole Contol Stategy fo Multi-Phae... THERMA SCIENCE: Yea 6, Vol., Suppl., pp. S48-S493 fully independent opeation of ix-phae SCIG in full peed ange, while VSI fulfil all the neceay equiement egading gid ynchonization. Ptub Six-phae induction machine Pgen Pout VSR VSI mm V Powe ytem ω T Wind model α Tubine model m m ia ic ib id 6 e j dq i d i q Speed etimation dq i - ω etimato ω u q uace u d u q 6 u bdf j dq e u d V DC u ga u gb u gc i gid Contol of gid ide convete V DC Q gid ugid iq id ω m n m + T n d T d d ωl ωdq dq d iq i d i q Reg i q i d Reg id ω P el ω mc 3 p m i q d i d Figue. Vaiable peed WECS with ix-phae SCIG and full-capacity powe convete Since the focu of thi pape i peed-enole vecto contol of ix-phae SCIG, contol of gid ide convete i pefomed uing tandad contol technique and thoe will not be dicued in detail. The machine ide convete i contolled uing well known indiect field oiented contol (IFOC), beneficial fo opeation in fou-quadant down to tandtill [8-]. Machine model and modulation tategy Mathematical epeentation of the aymmetical ix-phae induction machine ued in the pape i baed on voltage pace decompoition (VSD) theoy [, 3]. With the application of the amplitude invaiant VSD tanfomation matix, tato and oto equation fom the oiginal domain (a, b, c, x, y, z), ae tanfeed to thee two-dimenional othogonal (decoupled) ubpace (α, β, μ, μ, z, z ). The fundamental component ae contained in α-β ubpace a hown in eq. (), while the othe ubpace, deignated by μ -μ in eq. (), contain the lo poducing component. The thid, z -z ubpace containing zeo-equence component, equal to zeo in egad to the paticula topology, i not peented in thi pape. R d/dt d/dt l M M u i d/dt d/dt R M M u l i d/dt ' ' ' d/dt M i M R l M l M i d/dt ' ' ' d/dt M M l M R l M () u R d/dt i l d/dt i u R l d/dt R l i d/dt R l i ()

5 Dumni}, B. P., et al.: Speed-Senole Contol Stategy fo Multi-Phae... THERMA SCIENCE: Yea 6, Vol., Suppl., pp. S48-S493 S485 The machine toque in tationay efeence fame can be acquied by: P M T e 3 i i (3) Mathematical model afte tanfomation to the ynchonou otating efeence fame i identical to the thee-phae machine a it i peented in [7]. The contol of the machine ide convete i made accoding to the novel pace vecto election cheme peented in [7]. The main advantage of thi technique in compaion with tandad technique i excellent mitigation of component in μ -μ ubpace and utilization of the DC-link, while ignificantly implifying implementation [4]. Fo efeence vecto appoximation, election cheme ue thee lage vecto and one middle ize vecto. In ode to achieve thee vecto appoximation, pule-width modulation (PWM) technique, decibed in [7], vaie channel active high/active low logic duing tanition ove cetain ecto. Howeve, it i hown in [4] that thi can be achieved with PWM module of a commecially available digital ignal poceo (DSP). Speed etimation algoithm fo ix-phae SCIG The WECS envionment duing opeation uually conit of evee and hah condition with wide tempeatue and wind peed ange, heavy toque, vibation and fequently even chemically aggeive envionment (off-hoe intallation). Conequently, elimination of peed eno impove ytem obutne with the added benefit of ignificant eduction in egula and emegency maintenance cot. On the othe hand, infomation on the otational peed of geneato i neceay fo pecie IFOC contol. Thi ha led to numeou technique fo oto peed etimation to be developed [4-6, 5]. Baed olely on machine cuent and voltage meauement thee technique ae ued fo peed etimation in haft-enole dive. The mot popula method fo oto peed etimation i deived uing MRAS [4]. Etimation algoithm baed on MRAS ue cloed loop contol ytem and can, theefoe, be efeed to a an obeve. Thee main component of the MRAS obeve ae efeence model, adaptive model and adaptation mechanim, a hown in fig. 3. Both model ae mathematical epeentation of the machine that eflect cuent machine tate. Refeence model fail to featue value etimated by MRAS obeve, i. e. oto peed. Inight in the deied value (otational peed) i povided by the adaptive model, ince the mathematical epeentation contain etimated value of MRAS obeve. Accoding to a pedefined function, adaptive model align etimation to the actual peed Figue 3. The MRAS baed oto peed obeve. value, exploiting the diffeence between elevant value in efeence and adaptive model. Common name fo the efeence model i voltage etimato, wheea adaptive model i efeed to a cuent etimato. Claification of MRAS technique i made in accodance to the elected value fo compaion. Motly, tato flux, oto flux, back electomotive foce (EMF), active and eactive powe ae ued [4]. Pape ugget MRAS obeve baed on compaion of the oto flux, achieved uing machine voltage equation fo tato and oto winding.

6 S486 Dumni}, B. P., et al.: Speed-Senole Contol Stategy fo Multi-Phae... THERMA SCIENCE: Yea 6, Vol., Suppl., pp. S48-S493 Refeence model etimato can be epeented uing eq. (4). A it can be noted, thi etimato ue tato voltage and cuent in ode to calculate oto flux linkage component (Ψ d, Ψ q ). Choen efeence fame i indicated by the upecipt () in thee equation, and conideing the machine ued (SCIG), tationay efeence fame wa choen. In the equation epeent the tato tanient inductance. M u R i dt i d d d d M u R i dt i q q q q Voltage equation in tationay efeence fame ae ued fo the adaptive model etimato hown in eq. (5). Thi model ue tato cuent and peed ignal fo calculation of oto flux linkage component. Etimated quantitie ae denoted uing ymbol ^ in the following equation: d d d q ˆ T Mi ˆ ˆ T ˆ dt q q q d ˆ T Mi ˆ ˆ T ˆ dt Adaptation mechanim i baed on popotional-integal (PI) contolle type and i epeented by ωˆ = (Kp + K i /) ε, whee ε = Ψˆ dψ q Ψ dψˆ q. Thi mechanim i ued to align the etimated and actual value of the peed. Eo value, a evident, i popotional to the ine value of angle diffeence between output vecto of efeence and adaptive model. Integal gain in adaptation mechanim will enue that teady tate value of ε i equal to zeo. The pape popoe uing decibed MRAS algoithm fo peed etimation with ixphae SCIG topology fo WECS, enhancing the obutne and eliability of the ytem. Tanfe to the ix-phae ytem, fom well etablihed thee-phae MRAS peed etimation, i made uing imple extenion pinciple. On the othe hand, caued by the evee envionmental condition, themal dift can eaily make the machine eitance vay up to ±% in compaion with etimato pedefined value. In that egad, MRAS obeve with detuned paamete (tato and oto eitance) can be obeved a an encode with an inheent ipple, conequently leading to ocillation and intability of the WECS dive. Aide fom the influence on dynamic pefomance MRAS obeve paamete detuning will lead to peed etimation eo in teady tate [4]. Speed etimation eo in teady tate will alo lead to powe loe due to inaccuate peed value upplied to the MPPT algoithm, faulty opeation of pitch angle egulation ytem and faulty opeation of othe contol algoithm (e. g. powe limitation) that ue machine peed a a contol vaiable. In ode to deal with thee well-known inufficiencie, the impoved MRAS technique can be implemented applying the ame extenion pinciple [5, 6, 6]. Veification of theoetical pinciple The popoed theoetical conideation of applying known enole contol pinciple to a ix-phae SCIG ued in WECS ae veified uing Matlab/Simulink model of the ytem. Bai fo the model i epeented in fig.., while the imulation eult will how the ucceful implementation of MRAS peed etimation and decoupled vecto contol fo ix- (4) (5)

7 Dumni}, B. P., et al.: Speed-Senole Contol Stategy fo Multi-Phae... THERMA SCIENCE: Yea 6, Vol., Suppl., pp. S48-S493 S487 phae induction machine. Sepaate tage, with diffeent ampling time, fo cuent and peed contol ae et in the imulation. Speed etimation technique i veified uing peed cloed contol loop fo the ixphae machine with IFOC pinciple implemented. The flux wa et to the nominal value, and the machine wa fit acceleated to the efeence peed of 4 ad/, while the load toque wa kept at zeo. When the machine achieved teady tate, the load toque of Nm wa applied at the time.8 econd. The machine toque wa kept though the peed efeence change, afte which, at time.4 econd the toque wa et to zeo again. In fig. 4. ix-phae machine actual and etimated peed i peented, whee the obviou tanition of toque and peed can be noted. In addition, the etimated and actual peed match almot pefectly poviding the tong gound fo pactical peed enole dive implementation. High peciion of peed etimation will enue decoupled contol fo IFOC tategy, aligning the ynchonou otating efeence fame to the deied poition. The main pinciple of IFOC can be obeved in d- and q-axi cuent hown in fig. 5. A it can be een, the change in the toque poducing (q-axi) cuent fail to influence the cuent in d-axi et at.45 A. Thi will lead to the contant flux fo the duation of imulation. The change in the q-axi cuent ae fully compliant with the toque and peed tanition peviouly hown. Since the contol of the ix-phae machine i atifactoy, the cuent in the tationay efeence fame, hown in the fig. 6(a). ae cicula in hape. In addition, in fig. 6(b). the negligible lo poducing component can be obeved, howing the benefit offeed by the novel vecto election cheme ued. The novel vecto election cheme automatically neutalize cuent in μ-μ plane, which inceae efficiency of the ytem. Detailed analyi of efficiency of novel vecto election cheme, with compaion to tandad modulation technique can be found in [4]. I [A] w [ad - ] t [] Figue 4. Machine MRAS etimated and actual oto peed q-axi cuent Etimated oto peed d-axi cuent t [] Figue 5. Flux and toque poducing cuent Actual oto peed

8 Iα[A] I μ [A] S488 Dumni}, B. P., et al.: Speed-Senole Contol Stategy fo Multi-Phae... THERMA SCIENCE: Yea 6, Vol., Suppl., pp. S48-S493 a) b)..5. Iα[A] Iμ[A] (a) Iβ[A] I β [A] (b) Iμ[A] I μ [A] Figue 6. Cuent component in α-β (a) and μ-μ (b) ubpace In ode to futhe demontate the behaviou of MRAS peed etimation in WECS at low wind peed, the ix-phae machine wa ued in geneato opeating egime. Figue 7. how the MRAS epone duing ytem tat-up and opeation unde tubine toque at low wind peed. It i expected that MRAS hould have poo pefomance at low peed and duing tat-up opeation. Howeve, the natue of the WECS opeation allow contol algoithm to eaily deal with thi inufficiency, ince the ytem tat to opeate only when wind peed i above the cut-in peed of the WECS. The mot common induction geneato opeate at elatively high peed o the effect of incoect opeation of the peed etimation cheme at low peed i not expeed fo thi application. In addition, aymmetical ix-phae machine with ix pole, ued in thi imulation and expeiment, uually opeate at peed ange of - pm in WECS [3]. A popoed peviouly and demontated in fig. 7(b)., the toque at geneato haft i zeo until the wind peed upaed the cut-in value, at which point the peed etimation algoithm ha been tated. Thi avoid the poblem with zeo peed etimation and lead to high dynamic pefomance of MRAS peed etimation duing tat-up, a peented in fig. 7(a). 5 Etimated oto peed Actual oto peed w [ad - ] 5 5 (a) (a) t [] Figue 7. Speed etimation duing tat-up opeation (a) and the tubine toque (b) Expeimental validation of the popoed WECS enole contol cheme Deciption of aboatoy WECS Pototype T [Nm] Speed-enole contol tategy fo ix-phae SCIG ued in vaiable peed WECS with full-capacity convete popoed by thi pape i teted and veified uing advanced laboatoy pototype fo contol of electical dive and powe electonic con- - - (b) (b) t []

9 Dumni}, B. P., et al.: Speed-Senole Contol Stategy fo Multi-Phae... THERMA SCIENCE: Yea 6, Vol., Suppl., pp. S48-S493 S489 vete [7]. Advance eeach and development (R&D) tation developed by autho of thi pape ha the poibility of unning diffeent demanding complex contol tategie fo multi-phae ytem, tandad thee phae ytem, gid connected convete, electical vehicle and othe [8-3]. Peviouly peented theoy will be expeimentally validated by oganizing the etup to opeate a a mall cale WECS with aymmetical ixphae SCIG. The phyical outlook of the expeimental et-up can be een in fig. 8. Baic and complex contol olution ae implemented uing modula and highly veatile dspace contol hadwae [3]. In fig. 8. dspace poceo boad deignated by execute peed etimation, IFOC tategy and MPPT algoithm fo the contol of geneato ide convete deignated by and 3. Six-phae convete conit of two thee-phae convete haing the ame DC-link which ae contolled imultaneouly to behave a a ingle unit convete. Geneato ide convete i coupled by DC-link with gid ide convete, whee tandad contol technique ae implemented and will not be futhe dicued ince they ae not the focu of thi pape. Additionally, peentation of ealitic opeational condition efeence fo wind tubine emulato, coniting of powe convete 4 and toque contolled machine i dictated by the dspace ytem accoding to the actual wind data. Toque contolled machine i mechanically coupled with the ix-phae SCIG and coupled goup i maked by 5. Data acquiition, contol ignal and meaued ignal ae outed though adapte block indicated by 6. A powe tanfome 7 epeent the point of common coupling whee geneated powe i upplied to the ditibution netwok. Two ditibution cabinet deignated by 8 and 9 hold witching and potection gea. Uing full viual block oiented pogamming in Matlab/Simulink oftwae tool ealtime implementation algoithm peented in fig. 9. ha been developed. Fatet ubytem, containing meauement (ixphae SCIG cuent and DC-link volt-age), oftwae ytem potection and PWM geneation i executed at 8 khz ampling fequency and tiggeed by hadwae geneated inteupt at the midpoint of PWM peiod. Cuent contol and peed etimation ubytem i et to be executed at 4 khz, while the MPPT algoithm wa at khz; if the time contant of the WECS mechanical ubytem wa ignificantly highe and fate contol would be ineffective. Baic tigge block Figue 8. Small cale WECS laboatoy pototype Meauement and oftwae potection ubytem Down-ampling Cuent contol and peed etimation ubytem Down-ampling MPPT algoithm and peed contol ubytem Figue 9. Stuctual oganization of the contol algoithm fo eal-time implementation

10 S49 Dumni}, B. P., et al.: Speed-Senole Contol Stategy fo Multi-Phae... THERMA SCIENCE: Yea 6, Vol., Suppl., pp. S48-S493 Expeimental Reult Continuing on the pinciple veified by imulation, the complete mall cale WECS with ix-phae induction machine ha been developed uing peviouly decibed advanced a) T[Nm] - t[] b) I[A] q-axi cuent d-axi cuent t[] Figue. Emulated wind toque (a) with flux and toque poducing cuent (b) laboatoy pototype. Expeimental veification i ued to pove that a enole vecto contolled ix-phae SCIG could be ued in the popoed WECS topology adequately. Fo the opeation of WECS baed on ix-phae SCIG, and accoding to IFOC tategy pinciple, the machine flux i kept at nominal value by pope contol of d-axi cuent. The pogammed MPPT algoithm, baed on otational peed etimation, geneate the efeence value of the toque, and conequently q-axi cuent. Toque efeence i acquied uing wind data and wind tubine model defined in Wind Tubine Blocket fo Matlab/Simulink [3]. In fig. -3 expeimental eult of WECS with ix-phae SCIG unde vaiable aveage wind peed anging fom -3 m/ ae given. In fig., emulated wind toque at machine haft i peented. Figue. alo peent machine flux and toque poducing cuent, poving that decoupled contol with contant machine flux i achieved. Obeving the q-axi cuent, it can be eaily concluded that the maximum available wind powe i conveted to electical powe, thu poving the adequate implementation of IFOC with MPPT. Decoupled contol wa made poible due to ucceful implementation of enole contol and high peciion of oto peed etimation. A peented in fig., etimated peed ignal ha high pecentage match to the actual machine oto peed. A a futhe poof of contol quality fo the popoed tategy ix tato phae cuent duing WECS opeation ae inuoidal, a obeved in fig.. Accoding to VSD theoy and applied novel modulation tategy high efficiency contol ha been achieved. Veification of the fome i offeed by fig. 3, with negligible level of lo poducing cuent component (μ-μ), and α-β component of an ideal cicula hape. Etimated oto peed Actual oto peed 8 n[pm] n [pm] t[] t Figue. Machine MRAS etimated and actual oto peed

11 Dumni}, B. P., et al.: Speed-Senole Contol Stategy fo Multi-Phae... THERMA SCIENCE: Yea 6, Vol., Suppl., pp. S48-S493 S49 3 Iabcxyz [A] t [] Figue. Stato cuent in time domain IIμ [A] μ [A] [A] IIαα[A] (a) (a) (b) - - IβI[A][A] β (b) -.. I [A].... I μμ [A] Figue 3. Cuent component in α-β (a) and μ-μ (b) ubpace Concluion A wift development of the technology offe the poibility of implementing novel WECS topologie with impoved chaacteitic. Thi pape dicue advanced ytem fo conveion of wind enegy, equipped with ix phae induction geneato contolled by a peed enole IFOC technique. Obviou advantage ove tandad olution, epecially egading the peed eno enitivity to envionmental influence, ae povided uing MRAS peed etimation technique adapted fo the ue with aymmetical ix-phae induction machine. The IFOC contol algoithm and peciion of MRAS peed etimation ha been veified uing the imulation. It wa poven that it i poible to achieve obut and eliable peed enole contol, with atifactoy pefomance chaacteitic. Futhemoe, a novel modulation technique allowed fo the impovement of contol efficiency. Afte ucceful veification of theoetical pinciple, a mall cale WECS pototype featuing ix-phae SCIG ha been developed. Uing the developed pototype, the popoed topology wa teted unde tandad wind condition. Expeimental eult how that high dynamic pefomance of WECS with ix-phae induction geneato unde enole vecto contol wa achieved. Popoed topology ignificantly impove ytem eliability and obutne, while allowing WECS to ovecome key inufficiencie of tandad olution. In addition, the total loe of the ytem wee ignificantly educed by the ue of adequate modulation tategy. With the advantage offeed by multi-phae machine, and contol pinciple hown in thi pape, many of key inufficiencie of tandad WECS topologie can be mitigated.

12 S49 Dumni}, B. P., et al.: Speed-Senole Contol Stategy fo Multi-Phae... THERMA SCIENCE: Yea 6, Vol., Suppl., pp. S48-S493 Offeing tong contol olution, by a imple extenion pinciple, will lead to fat development of novel topologie in the field. In addition, novel contol tategie offeed by the intoduction of multi-phae machine ide convete will lead to ignificant impovement of poce efficiency. Acknowledgment Thi pape i a eult of the cientific poject No. III 44 of Integated and Intediciplinay Reeach entitled Smat Electicity Ditibution Gid Baed on Ditibution Management Sytem and Ditibuted Geneation, funded by Republic of Sebia, Minity of Education, Science and Technological Development. Nomenclatue i phae cuent, [A] K p popotional gain, [ ] K i integal gain, [ ] inductance, [H] M mutual inductance, [H] P numbe of pai pole, [ ] R eitance, [Ω] T e toque, [Nm] T oto time contant, [] u phae voltage, [V] Geek ymbol ω peed, [ad ] Ѱ flux linkage, [Wb] ε eo ignal, [ ] Refeence Supecipt Subcipt tationay efeence fame a, b, c, x, y, z quantitie in coeponding phae l leakage quantitie tato quantitie tato quantitie α,β,μ,μ,d,q coeponding value in adequate ubpace Othe ^ above ymbol denote etimated value [] ***, GWEC Repot, Global Wind Repot Annual Maket Update 4, Global Wind Enegy Council, 4 [] Patil, N. S., Bhole, Y. N., A Review on Wind Tubine Geneato Topologie, Intenational Confeence on Powe, Enegy and Contol (ICPEC), Dindigul, Tamil Nadu, India, 3, pp [3] Wu, B., et al., Powe Conveion and Contol of Wind Enegy Sytem, John Wiley and Son, IEEE Pe, USA, [4] Md Rabiul, I., et al., Powe Convete fo Wind Tubine: Cuent and Futue Development, Mateial and Pocee fo Enegy: Communicating Cuent Reeach and Technological Development, FOR- MATEX, pp , 3 [5] Blaabjeg, F., et al., Futue on Powe Electonic fo Wind Tubine Sytem, The Intitution of Engineeing Technology, IET, Electic Powe Application, EPA, (7), 4, pp [6] evi, E., et al., Multiphae Induction Moto Dive - A Technology Statu Review, IEEE Jounal of Emeging and Selected Topic in Powe Electonic, (3), 3, pp [7] Milićević, D., et al., New Space Vecto Selection Scheme fo VSI Supplied Dual Thee-Phae Induction Machine, Advance in Electical and Compute Engineeing, 3 (3),, pp [8] Paa,., On Advantage of Multi-Phae Machine, Indutial Electonic Society, 5. 3 t Annual Confeence of IEEE, IECON 5., Sheaton Capital Cente Raleigh, N.C., USA, 5 [9] Zhao, Y., ipo, T. A., Modeling and Contol of a Multi-Phae Induction Machine With Stuctual Unbalance Pat I, IEEE Tanaction on Indutial Electonic, (996), 3, pp [] Manteo Paola, E., Maina, G., An Optimized Contol Stategy fo Double Sta Moto Configuation in Redundancy Opeation Mode, Poceeding, Euopean Powe Electonic and Application Confeence EPE, auanne, Switzeland, 999 [] Golubev, A. N., Ignatenko, S. V., Anomalou Opeation of Multiphae Aynchonou Electic Dive, Ruian Electical Engineeing, 7 (),, pp. -8

13 Dumni}, B. P., et al.: Speed-Senole Contol Stategy fo Multi-Phae... THERMA SCIENCE: Yea 6, Vol., Suppl., pp. S48-S493 S493 [] evi, E., Multiphae Electic Machine fo Vaiable-Speed Application, IEEE Tanaction on Indutial Electonic, 55 (8), 5, pp [3] Bojoi, R., et al., Dual-Thee Phae Induction Machine Dive Contol-A Suvey, IEEJ Tanaction on Induty Application, 6 (6), 4, pp [4] Va, P., Senole Vecto and Diect Toque Contol, Oxfod Univ. Pe, NY, 998, ch. 4 [5] Va, P., Atificial-Intelligence-Baed Electical Machine and Dive: Application of Fuzzy, Neual, Fuzzy-Neual, and Genetic-Algoithm-Baed Technique, Oxfod Univeity Pe, 999, ch. 5 [6] Dumnić, B., et al., An Impoved MRAS Baed Senole Vecto Contol Method fo Wind Powe Geneato, Jounal of Applied Reeach and Technology JART, (), 5, pp [7] Che, H. S., et al., Cuent Contol of a Six-Phae Induction Geneato fo Wind Enegy Plant, Poceeding, 5 th Intenational Confeence on Powe Electonic and Motion Contol, EPE/PEMC, pp. S5b.--S5b.-7, Novi Sad, Sebia, [8] Santiteban, J. A., Stephan, R. M., Vecto Contol Method fo Induction Machine: An Oveview, IEEE Tanaction on Education, 44 (),, pp [9] Blaabjeg, F., et al., Tend in Powe Electonic and Contol of Renewable Enegy Sytem, Poceeding, 4 th Intenational Confeence on Powe Electonic and Motion Contol, EPE-PEMC, K- K9, Metopol ake Reot Ohid, Macedonia, [] Dandil, B., Tunce, S., Fou-Quadant Contol of Multilevel Invete Fed Induction Moto Dive, Jounal of Scientific and Indutial Reeach, 67 (8), 9, pp [] Ben Slimene, M., et al., Indiect Field-Oiented Contol fo Dual Stato Induction Moto Dive, Poceeding, th Intenational Multi-Confeence on Sytem, Signal & Device, SSD 3, pp. -6, Hammamet, Tuniia, 3 [] Zhao, Y., ipo, T. A., Space Vecto PWM Contol of Dual Thee-Phae Induction Machine Uing Vecto Space Decompoition, IEEE Tanaction on Induty Application, 3 (995), 5, pp. -8 [3] Hadiouche, D., et al., Space Vecto PWM Technique fo Dual Thee-Phae AC Machine: Analyi, Pefomance Evaluation and DSP Implementation, IEEE Tanaction on Induty Application, 4 (6), 4, pp. - [4] Milićević, D., et al., Oveview of the Six Phae VSI Contol Technique fo the Dual Thee-Phae Induction Machine Dive, Poceeding, PCIM Euope 5; Intenational Exhibition and Confeence fo Powe Electonic, Intelligent Motion, Renewable Enegy and Enegy Management, pp. -8, Nuembeg, Gemany, 5 [5] Holtz, J., Senole Contol of Induction Moto Dive, Poceeding of the IEEE, 9 (), 8, pp [6] Dumnić, B., et al., Atificial Intelligence Baed Vecto Contol of Induction Geneato Without Speed Seno fo Ue in Wind Enegy Conveion Sytem, Intenational Jounal of Renewable Enegy Reeach,. 5 (5),, pp [7] Dumnić, B., et al., Advanced aboatoy Setup fo Contol of Electical Dive a an Educational and Developmental Tool, EUROCON, pp , Zageb, 3 [8] Adžić, E., et al., Development of High-Reliability EV and HEV IM Populion Dive with Ulta-ow atency HI Envionment, IEEE Tanaction on Indutial Infomatic, 9 (3),, pp [9] Dumnić, B., et al., aboatoy Tet Bench fo Multi-Phae Machine and Powe Electonic in Electical Vehicle Application, Poceeding, 8 th Intenational Sympoium on Powe Electonic - Ee 5, No. T-8, pp. -5, Novi Sad, Sebia, 5 [3] Popadić, B., et al., Sophiticated Reeach and Development Station fo Contol of Gid Connected Ditibuted Enegy Souce, Poceeding, X Intenational Sympoium on Indutial Electonic IN- DE 4, pp. -5, Banja uka, Republic of Spka, B&H, 4 [3] ***, dspace manual, Modula Sytem Hadwae Intallation and Configuation Refeence, dspace gmbh, 4 [3] Iov, F., et al., Wind Tubine Blocket in Matlab/Simulink, UNI. PRINT Aalbog Univeity, 4 Pape ubmitted: Octobe 9, 5 Pape evied: Novembe 6, 5 Pape accepted: Decembe 3, 5