International Journal on Recent and Innovation Trends in Computing and Communication ISSN: Volume: 2 Issue:

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1 Intnational Jounal on Rnt and Innovation Tnds in Computing and Communiation ISSN: Volum: 2 Issu: Modl Rfn Adaptiv Systm (MRAS) Basd Spd Snsolss Vto Contol of Indution Moto Div P N H Phaninda Kuma 1, D M Dshpand 2, Manisha Duby 3 1 M.Th Shola in Eltial Dpatmnt, MANIT, Bhopal, India 2,3 Pofsso in Eltial Dpatmnt, MANIT, Bhopal, India 1 hmanthv@gmail.om 2 dinsh.dshpand1949@gmail.om 3 md_manit@yahoo.om Abstat - This pap psnts a Modl Rfn Adaptiv Systm (MRAS) basd spd snsolss stimation of vto ontolld Indution Moto Div. MRAS basd thniqus a on of th bst mthods to stimat th oto spd du to its pfoman and staightfowad stability appoah. Dpnding on th typ of tuning signal diving th adaptation mhanism, MRAS stimatos a lassifid into oto flux basd MRAS, bak.m.f basd MRAS, ativ pow basd MRAS and atifiial nual ntwok basd MRAS. In this pap, th pfoman of th oto flux basd MRAS fo stimating th oto spd was studid. Ovviw on th IM mathmatial modl is bifly summaizd to stablish a physial basis fo th snsolss shm usd. Futh, th thotial basis of indit fild ointd vto ontol is xplaind in dtail and it is implmntd in MATLAB/SIMULINK. Kywods - Modl Rfn Adaptiv Systm (MRAS), Snsolss Contol, Vto Contol, Indit Fild Ointd Contol. ***** I. INTRODUCTION Indution motos a uggd and inxpnsiv mahins, thfo muh attntion is takn whil implmnting th div systm fo vaious appliations with diffnt ontol quimnts [1]. An indution mahin has many advantags, spially ag oto indution mahin, whn ompad with DC mahin [2]. Howv, an indution mahin quis mo omplx ontol shms than DC motos baus of its highly nonlina and oupld dynami stutu [3]. Convntional opn-loop ontol of vaiabl fquny indution moto divs may povid a satisfatoy solution und limitd onditions. Howv, ths mthods a unsatisfatoy whn high pfoman dynami opation is quid. [4]. Thfo, highly dvlopd ontol shms a ndd to impov th pfoman of th indution moto div ompaabl with DC motos [5]. Rnt volutions in th aa of ontol systms, pow ltonis, powful and hap mioontolls, DC motos a plad by an indution moto in th industy. Vaiabl spd IM divs us mainly PWM thniqus to gnat a polyphas supply of a givn fquny [6, 7]. Most of ths indution moto divs a basd on kping a onstant voltag/fquny (V/f) atio in od to maintain a onstant flux in th mahin. Although th ontol of V/f divs is lativly simpl, th toqu and flux dynami pfoman is xtmly poo [7]. As a onsqun, a gat quantity of industial appliations that qui good toqu, spd o position ontol still us DC mahins [8, 9]. Ov th past fw dads a gat dal of wok has bn don into thniqus suh as Fild Ointd Contol, Dit Toqu Contol and Spa Vto Puls Width Modulation [1]. Fild ointd ontol (FOC) o vto ontol (VC) was intodud by Hass and Blashk fom Gmany, in 1969 and 1971 sptivly [6]. On th ontay to th sala ontol, th dvlopmnt of FOC ontol shm is basd on dynami modl of th IM wh th voltags, unts and fluxs a xpssd in spa vto foms [11]. Th psntation of th moto's quantitis using spa vtos valid und both stady stat and tansint onditions hn with FOC, xllnt tansint spons an b ahivd. Th oto flux FOC shm is basd on th fam tansfomation of all quantitis to a otating fam fixd to th oto flux. In this otating oto flux fam, all quantitis otating at synhonous spd will appa as DC quantitis [12]. If th flux is alignd to th d axis of this fn fam, thn th d omponnt of th stato unt psnt th flux and q omponnt of th stato unt psnt toqu omponnt. This mans that utilizing FOC, th ontol of IM is tansfomd to a simpl ontol shm simila to th DC moto ontol wh th toqu and flux omponnts a doupld. Th way th oto flux position is obtaind dtmins th typ of FOC as ith dit FOC o indit FOC. In indit FOC, th flux position is obtaind by adding th slip position to th masud oto position, wh as in dit FOC it is alulatd (o an also b masud) basd on th tminal vaiabls and oto spd [13]. Anoth mging aa of sah involvs th snsolss ontol of div systm whih is diffnt fom onvntional mthods baus it dosn t qui spd o position snsos. Rmoving ths snsos givs a numb of advantags suh as inasd liability, low podution osts, dud siz and moval of xss abling. Snsolss divs qui lss maintnan and a also mo suitabl fo hash inassibl nvionmnts [14]. Th study of spd snsolss ontol of th IM has undgon though matuing yas whn nw thniqus am into intodution to impov th pvious thniqus. Th motivation is to find on mthod that an at th nti poblm latd to spd snsolss IM. Among thm, MRAS basd thniqus hav bn povn to b on of th bst mthods bing poposd by th sahs du to its good high pfoman ability and staight-fowad stability appoah. Th mthod was fist poposd in [15] followd by [16] whih onsists of a fn modl (RM), an adjustabl modl (AM) and an adaptation mhanism. RM is indpndnt of th oto spd whas AM quis th oto spd infomation. Though Landau s ida of ompaing th outputs of RM and of AM, th o btwn th two modls an b minimizd using th adaptation mhanism [17]. IJRITCC Jun 214,

2 Intnational Jounal on Rnt and Innovation Tnds in Computing and Communiation ISSN: Volum: 2 Issu: Th pap has bn oganizd as follows: stion II bifly III. INDIRECT FIELD ORIENTED CONTROL xplains th mathmatial modling of indution moto, stion III dmonstat th indit Fild Ointd Contol of th indution moto div, stion Iibs th Roto Flux basd MRAS Spd Obsv, and th sults of implmntd Matlab modls a shown in stion V. II. MATHEMATICAL MODELLING Th dynami bhavio of an indution moto is omplx du to th oupling fft btwn th stato and oto phass. Fig. 1 shows th dynami d-q quivalnt iuits of an indution mahin. Th dynami modl of indution moto psntd in tms of voltags and unts an b givn in matix fom as [6]: V qs = V q V d R s + L s Þ ω L s L m Þ ω L m ω L s R s + L s Þ ω L m L m Þ. L m Þ ω ω L m + L Þ ω ω L s ω ω L m L m Þ ω ω L + L Þ Ths quations a xpssd in gnal fn fam dnotd by th supsipt and Þ psnts th divativ opato, d/dt. Th dynami modl of th indution moto an also b aangd with th stato and oto flux linkags as th stat vaiabls [6]. Ψ qs Ψ ds Ψ q Ψ d K τ ω s τ s ω = K s τ τ s τ K s τ ω ω K τ s ω ω Wh τ s = σ L s R s, τ = σ L, K s = L m L s τ Ψ qs Ψ ds Ψ q Ψ d V qs (2), K = L m, σ = 1 K L s K Th spd ω in th abov quations is latd to th toqu by th following mhanial dynami quation, V qs T T L = J dω + Bω dt (3) T = 3P Ψ 4 ds i qs Ψ qs (4) i qs R s R s ω λ ds λ qs L1s Lm L ω λ qs λ q (a) q-axis iuit λ ds L1s Lm L 1 λ d (ω -ω )λ d (ω -ω )λ q (b) d-axis iuit Fig. 1 Dynami d-q quivalnt iuits of an IM i q i d i qs i q i d V q V d A. Pinipl of Vto Contol To xplain pinipl of vto ontol, an assumption is mad that th position of oto flux linkags phaso, Ψ is known. Ψ is at θ f fom a stationay fn, θ f is fd to as fild angl haft, and th th stato unts an b tansfomd into q and d axs unts in th synhonous fn fam by using th pak s tansfomation givn blow [7]. IJRITCC Jun 214, I qs I ds I os = 2 3 os θ f os θ f 2π 3 os θ f + 2π 3 sin θ f sin θ f 2π sin θ 3 f + 2π Stato unt phaso, Is an b divd as I as I bs I s (5) I s = I 2 qs + I 2 ds (6) And stato phas angl is θ s = tan I qs I (7) ds wh I qs and I ds a th q and d axs unts in th synhonous fn fams that a obtaind by pojting th stato unt phaso on q and d axs, sptivly. That th unt phaso magnitud mains sam gadlss of th fn fam hosn to viw it is vidnt fom Fig. 2. Th unt phaso I s podus th oto flux and toqu T. Th omponnt of unt poduing oto flux phaso has to b in phas with. Thfo solving stato unt phaso along vals th omponnt i f is th fild poduing omponnt and i t is th toqu poduing omponnt ppndiula to it. By witing oto flux linkags and toqu in tms of ths omponnts Ψ i f (8) T Ψ i t i f i t (9) Fo vto ontol opation of th indution moto, th abitay fn fam must b alignd along th oto flux linkag spa phaso at vy instant. It is thfo ssntial that th position of th oto flux linkag spa phaso f, b auatly known at vy instant. Fom th Fig. 2, th instantanous oto flux phaso position, f an b wittn as θ f = θ + θ sl (1) Wh is th oto position and sl is th slip angl. In tms of th spds and tim, th fild angl is wittn as θ f = ω + ω sl dt = ω s dt (11) This knowldg of oto flux linkag spa phaso position an b aquid ith by masuing th flux ditly o by stimating th flux fom tminal vaiabls i.. by indit mans. This lads to two possibl ontol thniqus of indution moto namly: Dit fild ointd ontol and Indit fild ointd ontol. Ф θtθf θ s V s θ V qs θ sl I s I ds =i f I qs =i T Roto Rfn Fam Stato Rfn Fam Fig. 2 Phas diagam of vto ontol 1555

3 Intnational Jounal on Rnt and Innovation Tnds in Computing and Communiation ISSN: Volum: 2 Issu: B. Indit Fild Ointd Contol + Ψ = L m (16) In an Indit Fild Ointd Contol (IFOC) a flux stimato is usd to stimat th quid flux linkag spa phaso magnitud and angula position θ f as shown in Fig. 3. Th shaft position is usually ndd fo stimating flux linkag spa phaso position. This givs a mo adaptabl div systm, but this mthod would gnally sult in a mo omplx ontol systm [18]. Sin it is gnally dsiabl to hav a shm whih is appliabl fo all indution motos, th indit fild ointd has mgd as th mo popula mthod. In th indit fild ointatd ontol mthod th flux linkag spa phaso is stimatd fom th moto modl and whih is snsitiv to vaiations in mahin paamt lik th stato tim onstant o oto tim onstant. In th oto flux ointd ontol, th indit oto flux stimato is snsitiv to th oto tim onstant, of th moto. In stato flux ointd ontol, th indit stato flux stimato is snsitiv to th stato tim onstant of th moto. In th ai gap flux ointd ontol, th indit ai gap flux stimato is snsitiv to both th stato and th oto tim onstants. Thfo, if th valu of th moto paamt vais, th dsid doupld of th flux and th toqu omponnts of th stato unt spa phaso is not ahivd and this lads to du th pfoman of th dynami bhavio of th div systm. In this pap, only oto fild ointation ontol is onsidd. I qs,f I ds,f I qs I ds Toqu Contoll PI PI Flux Contoll V qs θ f V qso o V qs,f,f d -q Flux Estimato ab PWM Fig. 3 Blok diagam fo Indit Fild Ointd Contol C. Roto Flux Linkag Estimato Fo indit fild ointd ontol, it is ssntial to stimat th flux linkag spa phaso position. Thfo it is nssay to modl th oto flux linkags fo oto fild ointation thniqu. Fom th indution moto modling Fig. 1, by liminating th oto unts dψ d + Ψ dt L d L m R L ω sl Ψ q = (12) dψ q VSI d -q + Ψ dt L q L m R L i qs ω sl Ψ d = (13) wh ω sl =ω -ω Fo doupling ontol, it is dsiabl that Ψ q = (14) that is, dψ q = (15) dt So that th total oto flux is Ψ ditd on th d axis. Substituting th abov onditions in th qns. 12 & 13, w gt ab IM IJRITCC Jun 214, L dψ dt Ψ = L m 1+τ þ (17) dfining an quivalnt oto magntizing unt, i m as i m = Ψ L m (18) = i m + τ þi m (19) Fom th abov quation, th quivalnt oto magntizing unt i m is obtaind by passing th dit axis omponnt of th stato unt though a fist od low pass filt having tim onstant.th position of th oto flux linkag spa phaso is obtaind by intgating ω whih is givn by th sum of th ltial oto spd ω and th slip spd ω sl. If oto flux Ψ = onstant, whih is usually th as, thn fom qn. 16 Ψ = L m (2) In oth wods, th oto flux is ditly popotional to unt in stady stat. Wh ω sl is givn by ω sl = L m i qs τ Ψ (21) Fom qn. 21, ω sl = i qs τ (22) i qs IV. 1/τ 1/(1-þτ ) ω sl ω Fig. 4 Roto Flux Estimato ω 1/þ MODEL REFERENCE ADAPTIVE SYSTEMS (MRAS) MRAS is on of th most popula adaptiv ontol mthod usd in moto ontol appliations fo taking and obsving systm paamts and stats. Th a diffnt modl fn adaptiv ontol mthods suh as sis modl, paalll modl, dit modl and indit modl t. a availabl [14] [15]. Fig. 5 Gnalizd modl fn adaptiv systm MRAS stimatos onsist of fn modl and adjustabl modl as shown in Fig. 5.Th spd-adaptation laws adjusts th stimat spd basd on th outputs of fn and adjustabl modls. MRAS usd in this modl ompas both th outputs of a fn and adaptiv modls, θ f 1556

4 Intnational Jounal on Rnt and Innovation Tnds in Computing and Communiation ISSN: Volum: 2 Issu: and posss th o btwn ths two basd on th appopiat adaptiv laws that do not distub th stability of th applid systm [16]. In th MRAS thniqu, th dsid poss spons to a ommand signal is spifid by mans of a paamtially dfind fn modl. An adaptation mhanism kps tak of th poss output and th modl output and alulats a suitabl paamt stting suh that diffn btwn ths outputs tnds to zo [17]. An impotant issu in MRAS is th dsign of adaptiv laws. Th fist xampls of adaptiv law dsigns mad us of snsitivity modls, and lat th stability thoy of Lyapunov, and Popov`s hyp stability thoy, svd as standad dsign mthods, yilding a guaantd stabl adaptiv systm. In this pap, th dtail of th adaptation mhanism dsign is not laboatd sin it has bn laly disussd in [16] and [17]. A. Roto Flux MRAS Estimato In this MRAS shm th oto flux linkag (Ψ ) is usd as spd tuning signal. Th moto voltags and unts a masud in a stationay fam of fn. It is also onvnint to xpss ths quations in that stationay fam. Th spd an b alulatd by th modl fning adaptiv systm (MRAS), wh th output of th fn modl is ompad with th output of an adjustabl modl until os btwn th two modls vanish to zo. A blok diagam fo spd stimation by this MRAS thniqu is shown in th Fig. 6. Consid th voltag modl s stato sid quations (23) and (24) whih a dfind as a fn modl. Th modl ivs th mahin stato voltag and unt signals and alulats th oto flux vto signals, as indiatd. Fom th stato voltag quations in th stationay fam, th Rfn modl quations an b obtaind as: Rfn modl quations Ψ d = L v L ds L d (R m L s + σl )i s m dt ds (23) Ψ q = L v L qs L d (R m L s + σl )i s m dt qs (24) Wh Ψ is flux linkag, L, L m, L s a indutans, R s is sistan and σ = 1 L2 m is moto lakag offiint. Th L s L subsipts and s dnots th oto and stato valus, sptivly, fd to th stato and subsipts d and q dnot d-axis and q-axis omponnts in th stationay fn fam Th unt modl flux quations (25) and (26) a dfind as an adaptiv modl in th Fig. 6. This modl an alulat fluxs fom th input stato unts only if th spd signal ω is known. With th ot spd signal, idally, th fluxs alulatd fom th fn modl and thos alulatd fom th adaptiv modl will math, that is, Ψ d = Ψ d and Ψ q = Ψ q, wh Ψ d and Ψ q a th adaptiv modl outputs. An adaptation algoithm with P-I ontol, as indiatd, an b usd to tun th spd ω so that th o ξ =. Adaptiv modl quations Ψ d = L m T ω Ψ q 1 T Ψ d (25) Ψ q = L m T i qs + ω Ψ d 1 T Ψ q (26) wh ω is oto ltial spd and T = L is th oto tim onstant. Fig. 6 MRAS basd on oto flux stimation In dsigning th adaptation algoithm fo th MRAS, it is impotant to tak aount of th ovall stability of th systm and to nsu that th stimatd spd will onvg to th dsid valu with satisfatoy dynami haatistis. Using Popov s itia fo hyp stability fo a globally asymptotially stabl systm, w an div th following lation fo spd stimation: ω = ξ K p + K i (27) S wh ξ = X Y = Ψ d Ψ q Ψ q Ψ d (28) In stady stat ξ =, Balaning th fluxs; in oth wods, Ψ d = Ψ d and Ψ q = Ψ q. Th MRAS in th Fig. 6 an b intptd as a vto PLL in whih th output flux vto fom th fn modl is th fn vto and th adjustabl modl is a vto phas shift ontolld by ω. V. SIMULATION RESULTS Th following indution moto paamts a hosn fo th simulation studis: R s =.855Ω, = 1.15Ω, L s =.1432H, L =.1432H L m =.14 H, f = 5 Hz, J =.6 kg m 2, P = 6. Fig. 7 shows th omplt Simulink modl of indution moto, Fig. 8 shows th Simulink Modl of Roto Flux basd MRAS Spd stimato and Fig. 9 shows th omplt Simulink Modl of snsolss indit fild ointd ontol of indution moto with Roto Flux MRAS spd Obsv. Fig. 7 Simulink Modl of Indution Moto IJRITCC Jun 214,

5 Intnational Jounal on Rnt and Innovation Tnds in Computing and Communiation ISSN: Volum: 2 Issu: Fig. 11 spd o of th moto fo hangs in spd and load toqu Fig. 8 Simulink Modl of Roto Flux Basd MRAS Spd Obsv Fig. 12 Gnatd toqu of th moto with stp hangs in load toqu Fig. 9 Simulink Modl of Indit Fild Ointd Contol of IM Div with MRAS Spd Obsv Snsolss vto ontol simulation of th indution moto is psntd blow. Th spons of th indution moto is shown in two diffnt ass 1. with stp hangs in spd fn and load toqu 2. with spd vsal (Fou quadant opation) Fig. 13 Phas voltag vao and 3-ph unts of th moto with stp hangs in load toqu Fig. 1 Estimatd and fn spd of th moto with stp hangs in load toqu Fig. 14 Fou quadant Estimatd spd and fn spd Fom th abov sults w an onlud that With th appliation of th load only toqu omponnt i qs hangs but not flux poduing omponnt. IJRITCC Jun 214,

6 Intnational Jounal on Rnt and Innovation Tnds in Computing and Communiation ISSN: Volum: 2 Issu: Atual spd of th moto tas th Rfn spd isptiv of th load toqu within pmissibl limits. Th an b a slight dip in spd at th instant of appliation of load toqu but it should sttl to th fn spd aft som tim. Gnatd toqu (T) and load toqu (T L ) wavfoms follow th sam ta. VI. CONCLUSIONS In this pap, Indit Fild Ointd Contol and snsolss vto ontol with MRAS obsv thniqu fo th ontol of indution mahin a psntd. Fist, gnalizd dynami mathmatial modl of th indution moto is studid. Nxt, mathmatial modl of indution moto dvlopd in synhonous fn fam is simulatd and invstigatd. By using this moto dynami modl an indit fild ointation ontol is simulatd. An adaptiv stat obsv, MRAS is tstd to obsv oto spd. Th high pfoman of this shm is shown in simulation sults. Using this obsv, Snsolss vto ontol is simulatd and dq-axis oto-stato fluxs, oto spd w stimatd and found. In Snsolss vto ontol also pop fild ointation is ahivd baus th valu of q axis flux is zo and th is no hang in d axis unt du to th appliation of load toqu. Th MRAS povids th stimation of only on stat o on paamt instantanously. Thfo this ition dpnds on th quimnts of FOC algoithms. On may us MRAS not as a stat obsv but an onlin paamt tuning tool that tuns diffnt stat obsvs. VII. REFERENCES [1] R. Saidu, S. Mkhilf, M. B. Ali, A. Safai and H. A. Mohammd, Appliations of vaiabl spd div (VSD) in ltial motos ngy savings, Rnwabl and Sustainabl Engy Rviws 212; 16: [2] C. Saavanan, J. Sathiswa and S. Raja, Pfoman of th phas indution moto using modifid stato winding, Intnational Jounal of Comput Appliations 212; 46:1 4. [3] S. Amjad, S. Nlakishnan and R. Rudamoothy, Rviw of dsign onsidations and thnologial hallngs fo sussful dvlopmnt and dploymnt of plug-in hybid lti vhils, Rnwabl and Sustainabl Engy Rviws 21; 14: [4] C. A. Matins and A. S. Cavalho, Thnologial tnds in indution moto ltial divs, In Podings of IEEE Poto Pow Th, vol. 2; 21. [5] G. S. Buja and M. P. Kazmi kowski, Dit toqu ontol of PWM invt-fd AC motos a suvy, IEEE Tansations on Industial Eltonis 24; 51: [6] B. K. Bos, Pow Eltonis and AC Divs, Pnti Hall, 1986 [7] D. W. Novotny and T. A. Lipo, Vto Contol and Dynamis of AC Divs, Oxfod Univsity Pss In., Oxfod, Nw Yok, [8] E. A. Abdlaziz, R. Saidu and S. Mkhilf, A viw on ngy saving statgis in industial sto, Rnwabl and Sustainabl Engy Rviws 211; 15: [9] R. Saidu, A viw on ltial motos ngy us and ngy savings, Rnwabl and Sustainabl Engy Rviws 21; 14: [1] Y. Oguz and M Dd, Spd stimation of vto ontolld squil ag asynhonous moto with atifiial nual ntwoks, Engy Convsion and Managmnt 211; 52: [11] M. Hajian, G. R. Aab Makadh, J Soltani and S. Hosinnia, Engy optimizd sliding- mod ontol of snsolss indution moto divs, Engy Convsion and Managmnt 29; 5: [12] H. C. Stanly, An analysis of th indution motos, AIEE Tans., vol. 57, pp , [13] J. W. Finh and D. Giaouis, Contolld AC ltial divs, IEEE Tansations on Industial Eltonis 28; 55: [14] J. Holtz, Snsolss ontol of indution mahins: with o without signal injtion, IEEE Tansations on Industial Eltons 26; 53:7 3. [15] S. Tamai, H. Sugimoto and M. Yano, "Spd-snsolss vto ontol of indution moto with modl fn adaptiv systm", Conf. Rod of th 1985 IEEE-IAS Annual Mting, pp , [16] C. Shaud, "Adaptiv spd idntifiation fo vto ontol of indution moto without otational tansdus", IEEE Tans. Ind. Appliation, Vol. 28, No. 5, pp , Spt./Ot [17] Y.P. Landau, "Adaptiv Contol: Th modl fn appoah", Mal Dkk, Nw Yok, [18] O. Buak and L. M. Tolbt, Simulink implmntation of Indution Mahin Modl-A modula appoah, IEEE Tans Pow Eltonis, Vol. 39, No. 3, pp , May 23. IJRITCC Jun 214,