Mitigation of Harmonics and Real and Reactive Power Compensation under Unbalanced AC Source

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1 ville online t: Speil Issue from nd Ntionl onferene on omputin, letril, letronis nd Sustinle nery Systems, 6 th 7 th July 7, Rjhmundry, Indi Mitition of Hrmonis nd Rel nd Retive Power ompenstion under Unlned Soure h.jyothsn Rni M.John Sreenivs Ro PG Sholr, Deprtment of, Godvri Institute of nineerin nd Tehnoloy, Rjhmundry, ndhr Prdesh, Indi. sssitnt Professor, Deprtment of, Godvri Institute of nineerin nd Tehnoloy, Rjhmundry, ndhr Prdesh, Indi. To ite this rtile h.jyothsn Rni nd M.John Sreenivs Ro, Mitition of Hrmonis nd Rel nd Retive Power ompenstion under Unlned Soure, Interntionl Journl for Modern Trends in Siene nd Tehnoloy, Vol. 3, Speil Issue 4, July 7, pp. 8. STRT This pper presents the ontrol of rid interfin inverter with interted volte unlne orretion. It is proposed to dd n dditionl funtion to the inverter to derese the netivesequene volte t the point of onnetion with the utility rid. sed on symmetri sequene volte deomposition nd usin n improved multivrile filter, the ridinterfin inverter intentionlly sors smll mount of netivesequene urrent from the rid, therey helpin to orret the netivesequene volte. lthouh the mplitude redution ontriuted y eh individul inverter system is smll ompred to the totl netivesequene omponent, rid interfin inverter modules n olletively hieve sustntil results in the rid. The interted funtion nd proposed ontrol hs een verified in simultions nd y experiments on lortory prototype. This uide is useful to nyone who would like to ontriute to open soure projets on MTL. Open Soure is Gret Pltform for MTL nthusists to shre ide. Thnk you for your willinness to ontriute. Keywords ontrol strtey, d onverter, fult tolerne, unlned soure. opyriht 7 Interntionl Journl for Modern Trends in Siene nd Tehnoloy ll rihts reserved. I. INTRODUTION In mny importnt pplitions for power eletronis suh s renewle enery enertion, motor drives, power qulity, nd mirorid, et., the threephse d onverters re ritil omponents s the power flow interfe of d nd eletril systems [], []. s shown in Fi., d volte soure onverter with orrespondin filter is typilly used to onvert the enery etween the d us nd the threephse soures, whih ould e the power rid, enertion units, or the eletri mhines dependin on the pplitions nd ontrols [3] [5]. Sine the power eletronis re ettin so widely used nd eomin essentil in the enery onversion tehnoloy, the filures or shuttin down of these kone d onverters my result in serious prolems nd ost. It is eomin need in mny pplitions tht the power onverters should e relile to withstnd some fults or disturnes in order to ensure ertin vilility of the enery supply [6] [3]. ood exmple n e seen in the wind power pplition, where oth the totl instlled pity nd individul pity of the power onversion system re reltively hih. The sudden disonnetion of the power onverter my use sinifint impts on the rid stility nd lso on the hih ost for mintenne/repir []. s result, trnsmission system opertors (TSOs) in different ountries hve een issuin strit Interntionl Journl for Modern Trends in Siene nd Tehnoloy, Volume 3, Speil Issue 4, July 7

2 h.jyothsn Rni nd M.John Sreenivs Ro : Mitition of Hrmonis nd Rel nd Retive Power ompenstion under Unlned Soure requirements for the wind turine ehvior under rid fults. s shown in Fi., the wind power onverter should e onneted (or even keep enertin power) under vrious rid volte dips for ertin time ordin to the dip severity, nd in some unritil onditions (e.., 9% volte dip), the power onverter my need lontime opertion [], [], [], [3]. When the soure shown in Fi. eomes distorted under fults or disturnes, the unlned voltes hve een proven to e one of the retest hllenes for the ontrol of the d onverter in order to keep them normlly opertin nd onneted to the soure [], [4], [5]. Speil ontrol methods whih n reulte oth the positive nd netivesequene urrents hve een introdued to hndle these prolems [], [6] []. However, the resultin performnes y these ontrol methods seem to e still not stisftory: either distorted lod urrents or power osilltions will e presented, nd therey not only the soure ut lso the power onverter will e further stressed ompnyin with the ostly desin onsidertions. II. ONVRTR SYSTM WITH TH ZROSQUN URRNT PTH s n e onluded, in the typil threephse threewire onverter struture, four ontrol freedoms for the lod urrent seem to e not enouh to hieve stisftory performnes under the unlned soure. (No mtter wht omintions of ontrol trets re used, either sinifint power osilltion or overloded/distorted urrent will e presented.) Therefore, more urrent ontrol freedoms re needed in order to improve the ontrol performne under the unlned soure onditions. nother series of the onverter struture re shown s indited s the fourwire system in Fi. 9() nd the sixwire system in Fi. 9(). ompred to the threewire onverter struture, these types of onverters introdue the zerosequene urrent pth, whih my enle extr urrent ontrol freedoms to hieve etter power ontrol performnes. It is noted tht in the ridonneted pplition, the zerosequene urrent is not injeted into the rid ut trpped in the typilly used dy trnsformer. Fi.. Typil d power onverter pplition. () Fi.. Grid odes of wind turines under the rid volte dip y different ountries. This pper trets to understnd nd improve the power ontrol limits of typil threephse d onverter system under the unlned soure. new series of ontrol strteies whih utilizes the zerosequene omponents re then proposed to enhne the power ontrol ility under this dverse ondition. esides the rid intertion, the proposed ontrol methods hve the potentil to e pplied under other pplitions like the motor/enertor onnetions or mirorids, where the unlned volte is likely to e presented; therefore, the si priniple nd fesiility re minly foused. () Fi.3. onverter struture with the zerosequene urrent pth. () Fourwire system. () Sixwire system. Fi.4. ontrol struture for the onverter system with the zerosequene urrent. 3 Interntionl Journl for Modern Trends in Siene nd Tehnoloy, Volume 3, Speil Issue 4, July 7

3 h.jyothsn Rni nd M.John Sreenivs Ro : Mitition of Hrmonis nd Rel nd Retive Power ompenstion under Unlned Soure potentil ontrol struture is proposed in Fi., in whih n extr ontrol loop is introdued to enle the ontrollility of the zerosequene urrent. fter introduin the reulted zerosequene urrent, the threephse urrent enerted y the onverter n e written s Then, mtrix eqution s y opertin the volte of the soure () nd the urrent ontrolled y the power onverter(), the instntneous enerted rel power p, the iminry power q in the αβ oordinte, nd the rel power p in the zero oordinte n e lulted s It is noted tht unlike the trditionl pproh in whih the zero sequene omponents re normlly minimized, the zero sequene volte nd the urrent here look like sinlephse omponents runnin t the sme fundmentl frequeny. s result, the zerosequene volte/urrent n e represented y vetors in synhronous referene frme in the zero sequene s where the rel prt nd iminry prt n e represented s follows: Then, the instntneous threephse rel power p3φ nd the iminry power q3φ of the onverter n e written s It is noted tht the volte nd the urrent in zero sequene only ontriute to the rel power p3φ of the onverter. h prt of () n e lulted s It n e seen tht if the threephse soure volte is deided, then the onverter hs six ontrollle freedoms (i d, iq, i d, i q, i Re, nd i Im ) to reulte the urrent flowin in the soure. Tht mens: six ontrol trets/funtions n e estlished y the onverter hvin the zerosequene urrent pth. Similrly, the threephse vere tive nd retive power delivered y the onverter re two si requirements for iven pplition, then, two ontrol funtions need to e first settled s So, for the onverter system with the zerosequene urrent pth, there re four ontrol freedoms left to hieve two more ontrol trets thn the trditionl threewire system, this lsomens extended ontrollility nd etter performne under the unlned soure. III. LIMINTION OF OTH TH TIV ND RTIV POWR OSILLTION euse of more urrent ontrol freedoms, the power onverter with the zerosequene urrent pth n not only eliminte the osilltion in the tive power, ut lso nel the osilltion in the retive power t the sme time. This ontrol trets n e written s 4 Interntionl Journl for Modern Trends in Siene nd Tehnoloy, Volume 3, Speil Issue 4, July 7

4 Vd Id Disrete, s = 5e5 s powerui V pu v lph K Gin Vs V I Vd Ipv V (pu) MPPT Vs From Freq wt Sin_os 3phse PLL Vs sinos V_ref V Goto I Goto Susystem sinos Goto Vlph Vet Vm Vd From V (pu) Vs Is Freq wt Sin_os 3 3 Sope Ii From V I P referene PQ VLPH InVT 5e6 sin_os V V K V V fi5 in pper dq urrent Refferne Genertor onstnt sin_os dq K Gin urrent Mesurement error power v et v lph v et fi7 Is IsT* IsLPH* Gin In Goto7 MSURMNTS Is sinos [s] [s4] Ilph Iet Im Susystem Ismref Il Ismref [s3] [s6] Isl sinos [s5] [s] Ilph Iet Im Susystem dq sin_os [pn] [n] fi8 in pper v In From9 v lph v et Repetin Sequene Sope pulses From In In svm Out <= Reltionl Opertor pulses NOT Loil Opertor [pn] Goto9 [n] Goto Uref Pulses [s] Goto [s] Goto3 [s4] [s3] Goto4 Goto8 [s5] Goto5 [s6] Goto6 pulses h.jyothsn Rni nd M.John Sreenivs Ro : Mitition of Hrmonis nd Rel nd Retive Power ompenstion under Unlned Soure IV. SIMULTION RSULTS Disrete, Ts = 5e5 s. powerui v Id Vd PV ThreePhse Fult i Vs Is The power osilltion used y the zerosequene urrent P nd Ps re used to ompenste the power osilltion used y the positive nd netivesequene urrents P nd Ps. ontrollin 3phVS Tpulses Sope4 Sope6 Vi Vs Vs Is Ii sinl rms RMS V PQ I Sope5 Fi :7 onventionl Simultion Dirm _to_dq Trnsformtion dq_to_ Trnsformtion In order to filitte the nlytil solution, ssumin tht he dxis or the rel xis in the synhronous referene frme s llied with the volte vetors in eh of the sequene positive, netive, nd zero), nother promisin ontrol strtey for the onverter usin the zerosequene urrent pth is to eliminte the tive power osilltion, nd menwhile nel the netivesequene urrent. The extr two ontrol trets esides n e written 3phse PLL _to_dq Trnsformtion Fi :8 ontrol iruit Fi : 9 Three phse volte wve form Proposed iruit Simultion Results i Fi : Proposed Simultion iruit Simulink Dirm of Referene urrent enertor ( nd Sequene urrent enertors) 5 Interntionl Journl for Modern Trends in Siene nd Tehnoloy, Volume 3, Speil Issue 4, July 7

5 M (% of Fundmentl) M (% of Fundmentl) M (% of Fundmentl) h.jyothsn Rni nd M.John Sreenivs Ro : Mitition of Hrmonis nd Rel nd Retive Power ompenstion under Unlned Soure Seleted sinl: 5 yles. FFT window (in red): yles Time (s) x 3 Fundmentl (5Hz) = 8, THD=.4% Frequeny (Hz) Fi : 5 Volte wveform THD for proposed iruit without fult (.4%) omprison Tle THD for onventionl iruit durin fult 7% THD for onventionl iruit without fult 5% Fi : Netive Sequene Volte nd urrent THD for proposed iruit without fult.4% V. ONLUSION Fi : Positive Sequene Volte nd urrent Seleted sinl: 4 yles. FFT window (in red): yles Time (s) Fundmentl (6Hz) =.655, THD= 7.5% Frequeny (Hz) Fi : 3Volte wveform THD for onventionl iruit durin fult (7.5%) Seleted sinl: 4 yles. FFT window (in red): yles Time (s) Fundmentl (6Hz) =.658, THD= 5.4% Frequeny (Hz) Fi : 4Volte wveform THD for onventionl iruit without fult (5.4%) In typil threephse threewire onverter struture, there re four urrent ontrol freedoms, nd it my e not enouh to hieve stisftory performnes under the unlned soure, euse either sinifintly the osillted power or the overloded urrent will e presented. In the threephse onverter struture with the zero sequene urrent pth, there re six urrent ontrol freedoms. The extr two ontrol freedoms omin from the zero sequene urrent n e utilized to extend the ontrollility of the onverter nd improve the ontrol performne under the unlned soure. y the proposed ontrol strteies, it is possile to totlly nel the osilltion in oth the tive nd the retive power, or redued the osilltion mplitude in the retive power. Menwhile, the urrent mplitude of the fulty phse is sinifintly relieved without further inresin the urrent mplitude in the norml phses. The dvnte nd fetures of the proposed ontrols n e still mintined under vrious onditions when deliverin the retive power. The nlysis nd proposed ontrol methods re well reed y experimentl vlidtions. RFRNS [] F. ljer, M. Liserre, nd K. M, Power eletronis onverters for wind turine systems, I Trns. Ind. ppl., vol. 48, no., pp , Mr./pr.. [] R. Teodoresu, M. Liserre, nd P. Rodriuez, Grid onverters for Photovolti nd Wind Power Systems. New York, NY, US: WileyI,. 6 Interntionl Journl for Modern Trends in Siene nd Tehnoloy, Volume 3, Speil Issue 4, July 7

6 h.jyothsn Rni nd M.John Sreenivs Ro : Mitition of Hrmonis nd Rel nd Retive Power ompenstion under Unlned Soure [3] J. Roert, G. M. S. zevedo,. Lun, J. M. Guerrero, J. I. ndel, nd P. Rodriuez, Intellient onnetion ent for threephse ridonneted mirorids, I Trns. Power letron, vol. 6, no., pp , Ot.. [4] J. W. Kolr nd T. Friedli, The essene of threephse PF retifier systems Prt I, I Trns. Power letron., vol. 8, no., pp , Jn. 3. [5] J. Hu, L. Shn, Y. He, nd Z. Z. Zhu, Diret tive nd retive power reultion of ridonneted d/ onverters usin slidin mode ontrol pproh, I Trns. Power letron., vol. 6, no., pp., Jn.. [6]. Wessels, F. Gehrdt, nd F. W. Fuhs, Fult ridethrouh of DFIG wind turine usin dynmi volte restorer durin symmetril nd symmetril rid fults, I Trns. Power letron., vol. 6, no. 3, pp , Mr.. [7] F. hili, Fulttolernt torque ontrol of LD motors, I Trns. Power letron., vol. 6, no., pp , Fe.. [8] Y. Xinwu, G. Venktrmnn, W. Yn, D. Qin, nd Z. o, Gridfult tolernt opertion of DFIG wind turine enertor usin pssive resistne network, I Trns. Power letron., vol. 6, no., pp , Ot.. [9].. Welhko, T.. Lipo, T. M. Jhns, nd S.. Shulz, Fult tolernt threephse motor drive topoloies: omprison of fetures, ost, nd limittions, I Trns. Power letron., vol. 9, no. 4, pp. 8 6, Jul. 4. [] F. ljer, K. M, nd D. Zhou, Power eletronis nd reliility in renewle enery systems, in Pro. I Int. Symp. Ind. letron., My, pp [] Y. Son nd.wn, Survey on reliility of power eletroni systems, I Trns. Power letron., vol. 8, no., pp , Jn. 3. [] M. ltin, O. Goksu, R. Teodoresu, P. Rodriuez,. kjensen, nd L. Helle, Overview of reent rid odes for wind power intertion, in Pro. th Int. onf. Optim. let. letron. quip.,, pp [3] Grid ode. Hih nd xtr Hih Volte,.ONnetz, yreuth, Germny, pr. 6. [4] P. Rodr ıuez,. Lun, R. Mu nozuilr, I. txeerriotdui, R. Teodoresu, nd F. ljer, sttionry referene frme rid synhroniztion system for threephse ridonneted power onverters under dverse rid onditions, I Trns. Power letron., vol. 7, no., pp. 99, Jn.. [5]. J. Rosoe, S. J. Finney, nd G. M. urt, Trdeoffs etween power qulity nd D us ripple for 3phse 3wire inverteronneted devies within mirorids, I Trns. Power letron., vol. 6, no. 3, pp , Mr.. [6]. H. N, Li Rn, nd J. umy, Unlnedridfult ridethrouh ontrol for wind turine inverter, I Trns. Ind. ppl., vol. 44, no. 3, pp , My/Jun. 8. [7] P. Rodriuez,. V. Timus, R. Teodoresu, M. Liserre, nd F. ljer, Flexile tive power ontrol of distriuted power enertion systems durin rid fults, I Trns. Ind. letron., vol. 54, no. 5, pp , Ot. 7. [8] H. Son nd K. Nm, Dul urrent ontrol sheme for PWM onverter under unlned input volte onditions, I Trns. Ind. letron., vol. 46, no. 5, pp , Ot [9] H. ki, Y. Knzw, nd. Ne, Instntneous retive power ompenstors omprisin swithin devies without enery store omponents, I Trns. Ind. ppl., vol. I, no. 3, pp , My 984. [] J. Miret, M. still,. mho, L. Viu n, nd J. Mts, ontrol sheme for photovolti threephse inverters to minimize pek urrents durin unlned ridvolte ss, I Trns. Power letron., vol. 7, no., pp , Ot.. [] F. Gonz lezsp ın, G. Grer, I. Ptro, nd. Fiueres, n dptive ontrol system for threephse photovolti inverters workin in polluted nd vrile frequeny eletri rid, I Trns. Power letron., vol. 7, no., pp , Ot.. [] G. Somndo, J. Svensson, nd. Snnino, Improvin volte disturne rejetion for vrilespeed wind turines, I Trns. nery onvers., vol. 7, no. 3, pp. 4 48, Sep.. [3] N. Kminski nd. Kopt, Filure rtes of HiPkModules due to osmi rys, Switzerlnd Ltd., Zurih, Switzerlnd, ppl. note 5SY 44, Mr.. [4] S. Shrm nd. Sinh, Performne of volte nd frequeny ontroller in isolted wind power enertion for threephse fourwire system, I Trns. Power letron., vol. 6, no., pp , De.. [5] K. M, F. ljer, nd M. Liserre, Therml nlysis of multilevel rid side onverters for mw wind turines under low volte ride throuh, I Trns. Ind. ppl., vol. 49, no., pp. 99 9, Mr./pr. 3. [6] J. Holtz nd N. Oikonomou, Optiml ontrol of dul threelevel inverter system for mediumvolte drives, I Trns. Ind. ppl., vol. 46, no. 3, pp. 34 4, My/Jun.. [7]. H. Wtne, R. M. Stephn, nd M. redes, New onepts of instntneous tive nd retive powers in eletril systems with eneri lods, I Trns. Power Del., vol. 8, no., pp , pr Interntionl Journl for Modern Trends in Siene nd Tehnoloy, Volume 3, Speil Issue 4, July 7

7 h.jyothsn Rni nd M.John Sreenivs Ro : Mitition of Hrmonis nd Rel nd Retive Power ompenstion under Unlned Soure [8] M. redes nd. H. Wtne, New ontrol lorithms for series nd shunt threephse fourwire tive power filters, I Trns. Power Del., vol., no. 3, pp , Jul [9] M. redes, J. Hfner, nd K. Heumnn, Threephse fourwire shunt tive filter ontrol strteies, I Trns. Power letron., vol., no., pp. 3 38, Mr [3].T. Lee,.W. Hsu, nd P.T. hen, lowvolte ridethrouh tehnique for ridonneted onverters of distriuted enery resoures, I Trns. Ind. ppl., vol. 47, no. 4, pp. 8 83, Jul./u.. 8 Interntionl Journl for Modern Trends in Siene nd Tehnoloy, Volume 3, Speil Issue 4, July 7