Sensorless Control of an IPM Synchronous Motor for City-Scooter Applications

Transcription

1 Sensoless Contol of an IPM Synchonous Moto fo Cty-Scoote Applcatons Maco Tusn, Robeto Petella, Fancesco Paaslt Depatment of Electcal Engneeng Unvesty of L'Aqula I-674 Monteluco d Roo, L Aqula, Italy tusn@ng.unvaq.t, petella@ng.unvaq.t, ock@ng.unvaq.t Abstact Ths pape pesents the actvty made by the authos wthn the Natonal Reseach Pogam PRIN, patally suppoted by the Italan Mnsty of Instucton, Unvesty and Reseach (MIUR). The eseach has concened the development of a sensoless contolle fo nteo pemanent magnet (IPM) synchonous motos to be used n cty-scoote applcaton. The poject esult has been the desgn of a sensoless scheme sutable fo geneal applcatons whee low speed and standstll such as hgh speed opeatons ae equed. The fnal soluton conssts n an hybd technque employng an adaptve obseve fo medum/hgh speed opeaton and a sgnal njecton based technque fo low speed and standstll opeaton. The obseve detects the oto magnet flux components n the two-phase statonay efeence fame usng the moto electcal equatons. The moto speed s dentfed by a model efeence adaptve scheme usng an addtonal equaton obtaned by a Lyapunov functon. The analytcal development of the obseve s fully explaned. The convegence of the estmates at low speeds and standstll s acheved though the assstance of a hgh fequency sgnal njecton technque. Realstc smulatons accountng fo the naccuacy of an actual dgtal sgnal pocesso (DSP) mplementaton and the pototypal mplementaton on a commecal hadwae fo ctyscoote applcaton ae pesented and dscussed. Keywods sensoless contol, adaptve obseve, nteo PM synchonous moto, sgnal njecton I. INTRODUCTION. Recent poposals n emegng applcaton felds such as electc vehcles have outlned an nceasng nteest n the so-called nteo pemanent magnet (IPM) synchonous moto, whose basc chaactestc s epesented by the constucton wth magnets dsplaced nsde the oto body, [1]). The IPM motos shae wth the non-salent countepat (the cylndcal o suface PM motos, bult wth magnets dsplaced on the oto suface) some nteestng popetes, such as the absence of oto losses (that calls fo cool oto and nceasng effcency) and the hgh toque vs. weght ato. Addtonal featues, due to the patcula desgn of IPMs, ae the obustness of the oto stuctue (mechancally suted to hgh speed opeaton) and the pesence of magnetc salency. In fact, fom a magnetc pont of vew, IPM motos exhbt a salency ato dffeent fom unty,.e. the dect d-axs nductance s substantally dffeent fom the quadatue q- axs nductance, whee the d-axs s usually selected to be algned wth the PM flux axs. Ths chaactestc s patculaly suted fo extendng the speed opeatng egon by pope feld weakenng contol technques and, also, t allows the applcaton of some nteestng appoaches to poston and speed detecton (self-sensng o sensoless contol). Among the poposals n ths feld, two knds of appoaches seem to be pefeable, dependng on the speed opeatng ange equed by the applcaton: state obseves and sgnal njecton technques. State obseves ae pefeed fo medum/hgh speed opeaton. They eque the use of a elatvely accuate moto model, the measuement of the moto cuents (system output) and the knowledge of the feedng voltages (system nput). The basc dea s to use the dffeence between the state vaables and the estmated state vaables to calculate the oto poston and speed, dectly o though elated vaables. Seveal appoaches ae epoted n lteatue, most of them appled to non salent motos. Both detemnstc (Luenbege [5], [6]), non-lnea (sldng mode [7]) and stochastc (extended Kalman fltes [8]) obseves have been poposed, whch exhbt dffeent peculates n tem of algothm complexty and senstvty to paamete vaaton and nose. Adaptve appoaches based on the model efeence adaptve system (MRAS) theoy have been also suggested, [9]. Bascally the man lmtatons of the obseve based solutons efe to standstll/low speed opeatons and safe statng. Sgnal njecton technques ae the last fonte of eseach n sensoless contol of IPM motos. These methods take advantage of the constuctve magnetc salency of the machne to detect the oto poston though the njecton and back-pocessng of pope test sgnals [1], [11], [1]. They offe a soluton both fo standstll and low speed opeatons. As dawbacks they eque hgh pecson n the measuement, a cetan degee of ejecton to nose and dstubances, and hgh accuacy n sgnal pocessng especally when full-dgtal solutons ae consdeed and/o low salency motos ae employed.

2 In ths eseach an hybd sensoless soluton fo speed sensoless feld-oented contol of nteo pemanent magnet (IPM) synchonous motos has been developed, consstng n an adaptve obseve fo medum/hgh speed opeaton and a sgnal njecton based technque fo low speed and standstll opeaton. The obseve detects the oto magnet flux components n the two-phase statonay efeence fame usng the moto electcal equatons. The moto speed s dentfed by a model efeence adaptve scheme usng an addtonal equaton obtaned by a Lyapunov functon. The convegence of the estmates at low speeds and standstll s acheved though the assstance of a hgh fequency sgnal njecton technque. Both smulaton and expemental esults ae pesented, the last acheved by the mplementaton of a pototypal system usng a commecal hadwae fo cty-scoote applcaton. The system pefomance at dffeent speed anges ae pesented and dscussed. II. ADAPTIVE OBSERVER. The adaptve speed and poston obseve fo medum/hgh speed and opeaton s pesented n [] and [3]. The electcal equatons of the IPM synchonous moto n tems of stato fxed axs components α-β ae as follows: d ψ v = R + (1) d t ( θ ) ψ ( ) = L + () ψ M, θ whee v, and ψ ae vectos of the voltage/ cuent/ stato flux components espectvely, R s the esstance of the stato wndngs, L s the matx of the wndng nductance and: cosθ ψ M,( θ ) = ψm (3) snθ s the vecto of the flux lnkage components due to the magnet, whose poston s measued by the angle θ and whose ampltude s ψ M, (see Fgue 1). The flux model can be expessed n a moe useful fom n tem of oto fxed axs components d-q as follows: q C B S β s N θ ψ s ψ M d A α Fgue 1. Flux and cuent space vectos n an IPM synchonous moto. ω ( ) ψ = Ldq dq ψ M dq ψ dq = T θ +, (4) whee T ( θ ) s the α-β to d-q tansfomaton matx, dq = [ d, q ] s the vecto of the d-q cuent components, and: Ld ψm L dq =, ψm, dq = (5) Lq beng L d and L q the dect and quadatue synchonous nductances espectvely. Accodng to the pevous elatons, the voltage equaton n (1) and the flux model (4) can be aanged to buld a flux obseve as follows (Fgue ): v, d d t Voltage model K 11 Flux model θ ψ = T = T = T ψ dq ψ Fgue. Flux obseve. = v R + K 11 Angle calculaton ( ψ ) 1 ( θ ) ψdq = 1 ( θ ) ( Ldq dq + ψm, dq ) = 1 ( θ ) ( Ldq T( θ ) + ψm, dq ) whee s the stato flux acheved by the voltage model (compae Equatons (1) and (6)), ψ and ψ dq epesent the same flux as povded by the flux model (espectvely n tems of α-β and d-q components), K 11 s a x gan matx used to feedback the voltage model by the dffeence between the fluxes estmated by the same voltage model and by the flux model, and θ s the oto magnet poston calculated as follows: ψdq θ = actg (8) ψdq e ψ (6) (7)

3 whee the symbols ^ and epesent the vecto and dot poducts espectvely. Accodng to (3), the flux lnkage due to the oto magnet can be epesented by the dynamcal model: d ψm, = ω J ψm, (9) dt whee 1 J =. 1 Fom ths assumpton, an adaptve obseve whch estmates the oto magnet flux and the speed can be aanged as follows (Fgue 3): e ψ Invese flux model θˆ î e K M, K 1 Roto magnet flux model Angle calculaton Speed dentfcaton Fgue 3. Adaptve magnet flux and speed obseve. d M, = ω ψ ˆ M, + K1 eψ + K d t θˆ ˆ J e (1) = k P eω + k I eω dt (11) whee e = ( ˆ ) s the dffeence between the measued cuent and ts estmate, the latte obtaned by the ntoducton of an nvese flux model; e ( ˆ ψ = ψ ψ ) s the flux estmaton eo obtaned by the flux obseve; eω = eα Mβ eβ Mα s the speed eo, acheved by a Lyapunov appoach; K 1, K ae x gan matces used n the oto magnet flux obseve; k P, ki ae popotonal/ntegal gans used n the speed dentfcaton equaton;, θ ˆ ae the estmated oto speed and poston, the latte gven by: β θˆ M = actg ψ ˆ (1) Mα The avalablty of the cuent eo e allows to ntoduce a cuent feedback also n the flux obseve, n ode to mpove the obustness of the oveall system. Theeafte, equaton (7) takes the fom: d dt = v R + K11eψ + K1e (13) beng K 1 the gan matx x used to feedback the cuent eo. III. SIGNAL INJECTION. The sgnal njecton technque employed fo low speed and standstll opeaton s pesented n []. It s based on the voltage njecton pncple and conssts n a modfed pocessng of the hgh fequency cuents and the use of a Kalman flte obseve fo the extacton of the oto speed and poston nfomaton. The method s befly ecalled n the followng. The voltage njecton pncple was ognally poposed by Coley and Loenz n [1]. It eles on the fact that, by neglectng the satuaton of the magnetc ccuts and the elated coss-couplng effect, the d- and q-axs of the moto ae magnetcally decoupled fom each othe. Moeove, consdeng to nject an hgh fequency voltage, the esstve voltage dops ae neglgble wth espect to the eactve ones. Wth these hypotheses, the njected hgh fequency flux d-q components n the estmated ( θˆ ) oto poston efeence ae gven by: ψ ψ θˆ qs θˆ ds V = ω s sn 1 ( ω t) (14) whee ω and V s ae the cae pulsaton and the ampltude of the njected voltage, and V s /ω s the magntude of the coespondng flux. As a esult, the hgh fequency cuent components n the estmated oto poston efeence fame can be expessed as follows: θ qs whee beng = I I θ ds sn V = I 1 sn ( ω t) sn[ ( θ θ )] ( t) I sn ( ω t) cos[ ( θ θ )] ω 1 L s s =, I 1 ω L L ω L L L q + L d L =, (15) V L = (16) L q L d L = (17) the aveage value and the ampltude of the spatal modulaton of the nductance espectvely, L d and L q the d- and q-axs nductances. Fom (15) t can be seen that cae fequency sgnals ae poduced both on the d- and q-axs components, that ae non-lnealy ampltude-modulated by twce the dffeence between the estmated and the actual (θ ) poston. In ths poposal both the d- and q-axs components of the hgh fequency cuent n the estmated

4 efeence fame ae pocessed, n ode to extact the oto poston estmaton eo sgnal. In fact, the ampltude modulaton of both (15): εd I1 [ ( θ )] = sn θ εq I I1 [ ( θ )] = cos θ (18) can be evaluated by means of a pope demodulaton engne, []. Theeafte, assumng the constant offset I s dentfed, the oto poston eo (ε θ ) can be expessed as follows: 1 1 εd ε = θ tan (19) I εq whee ε d and ε q denote the eo sgnals extacted by each cuent component. By ths appoach a staghtfowad elatonshp between the eo sgnal and the actual oto poston estmaton eo s acheved. Once the eo sgnal (19) has been evaluated, t s used n a Kalman flte whch povdes the oto poston and speed estmaton, Fgue 4. Detals on Kalman flteng ae gven n [3]. ε d ε q I Eq. (19) ε θ Kalman flte θˆ equal to 45 degees) followed by a step vaaton of the speed efeence fom zeo to a gven set pont, wth 1.17 Nm (. pu) load toque. Fo the sake of compason, ths knd of test s epeated n the followng cases: 1) (Fgue 5 to Fgue 7): assumng, fo the sensoless opeaton, the sgnal njecton technque descbed n Secton III only: n ths case the low/medum speed opeatng egon s exploed assumng 45 pm and 75 pm set ponts, espectvely.15 and.5 p.u.. ) (Fgue 8 to Fgue 9): assumng, fo the sensoless opeaton, the sgnal njecton at standstll, and the adaptve obseve descbed n Secton II afte statup: n ths case the medum/hgh speed opeatng egon s exploed assumng 15 pm and 5 pm set ponts, espectvely.5 and.75 p.u.. As fo the sgnal njecton technque, a oto poston estmaton eo s pesent at steady state, whch nceases wth the opeatng speed, (Fgue 5 and Fgue 6). Such an eo, whch s ndependent on the load (.e. cuent) condtons (see Fgue 7) s due to the delays of the dgtal mplementaton, and can assume excessve values wth nceasng speed, leadng to a lack of contol. In a pactcal case, t must be compensated fo opeaton at medum speed, wheeas t can be accepted f opeaton at vey low speed and standstll s assumed. In Fgue 5 and Fgue 6, the nfluence of the Kalman flte acceleaton paamete a ( s pesented. Assumng a value dffeent fom zeo, popotonal to the dffeence between the efeence and the estmated speed, allows to mpove the pecseness of the speed estmaton dung the fast tansents, whle t does not affect the steady state opeaton and oto poston eo. Fgue 4. Poston and speed estmaton by Kalman flte (sgnal njecton technque) [pu] ω IV. SIMULATION RESULTS. In ode to gve a meanngful dea of the system pefomance, ealstc smulatons ae caed out efeng to the actual dgtal sgnal pocesso (DSP) mplementaton. The commecal IPM moto fo cty scoote applcaton s consdeed, whose paametes ae epoted n TABLE I, wheeas the chaactestcs efeng to the hgh-fequency sgnal njecton ae epoted n TABLE II. Synchonzed contol, PWM and cuent samplng peods of µs ae consdeed, wth the consequent tme-delays. Moeove the poblems elated to cuent measuement have been accounted. In fact, the elablty of the sensoless scheme, patculaly fo the sgnal njecton technque, s heavly affected by the accuacy of the hgh-fequency cuent components measuement The fst goal of smulatons s to compae the dffeent pefomance of the sgnal njecton technque and the adaptve obseve n tems of speed esponse and poston estmaton eo. The tested cases efes to a standstll opeaton (wth ntal oto poston and estmaton eo ω (s ) [degees] θ θˆ (s) ω =.15;.5 pu Fgue 5. Sensoless opeaton wth sgnal njecton technque (Kalman flte paamete a ( = ).

5 .35 [pu] 1 [pu].3 ω ω.5. ω (s ).75 ω (obs ) [degees] 5 [degees] θ θˆ (s) ω =.15;.5 pu 1 θ θˆ (obs ) ω =.5;.75 pu Fgue 6. Sensoless opeaton wth sgnal njecton technque ( (Kalman flte paamete a = k ( ω (s) ) ) Fgue 8. Sensoless opeaton wth adaptve obseve (ntegal gan k I =. 75 used n the speed dentfcaton equaton). load toque [pu] 1 [pu] ω ω (obs ) [degees] ω = pu θ θˆ (s) Fgue 7. Roto poston estmaton eo at steady state (sgnal njecton technque). As fo the adaptve obseve, the oto poston estmaton eo at steady state seems to be ndependent on the opeatng speed. Nevetheless, t s stongly affected by the choce of the seveal obseve gans. As an example, the counteactng nfluence of the ntegal gan k I used n the speed dentfcaton equaton s shown, by the compason of Fgue 8 and Fgue 9. If ths gan s too small, the speed and the poston estmates assume an oscllatoy behavo, whch can lead to nstablty dung lage (and fast) tansents. Fom the pesented esults, t ases that the sgnal njecton technque can be used to acheve good opeaton at standstll and (eventually) vey low speed, whle the adaptve obseve, wth pope gans, n the emanng speed ange. The stategy adopted to manage the opeaton of the hybd obseve s esumed as follows: [degees] θ θˆ (obs ) ω =.5;.75 pu Fgue 9. Sensoless opeaton wth adaptve obseve (ntegal gan k I =. 1 used n the speed dentfcaton equaton). 1) At standstll, the speed command s zeo, the estmates employed fo sensoless contol ae povded by the sgnal njecton technque. In the meantme the adaptve obseve s tuned by substtutng the estmated poston ( θ ) (see the scheme n Fgue ) wth the one povded by the sgnal njecton obseve.

6 ) Once the moto stats, the estmated speed nceases. When a fst commutaton level s eached (.e. estmated speed geate than.1 p.u. plus an addtonal hysteess band) the contolle swtches to the estmates povded by the adaptve obseve. Fom ths pont on, the sgnal njecton obseve s tuned by substtutng, at each contol step, the ntegal components of the Kalman flte (both speed and poston estmates) wth the coespondng values povded by the adaptve obseve. 3) Theeafte, when a second commutaton level s eached (.e. estmated speed geate than. pu plus an addtonal hysteess band), the hgh fequency sgnal njecton s emoved. Snce ths nstant the adaptve obseve acts alone. Once sgnal njecton ceases, the full voltage capacty of the feedng DC bus s avalable fo the fundamentals opeaton,.e. the maxmum speed ange can be attaned. Moeove, the powe losses due to the hgh fequency cuents and the vbatons due to the hgh fequency toque pple fnsh. V. EXPERIMENTAL RESULTS. The sensoless soluton developed wthn the eseach poject has been mplemented and expementally tested usng a commecal dve (and IPM moto) fo cty-scoote applcaton. Fgue 1 shows the expemental set-up. The sensoless contolle has been ealzed usng a TMS3C4 Evaluaton Module (EVM). The EVM has been ntefaced wth the commecal hadwae n ode to ead the cuent sgnals (fom the Hall sensos) and geneate the pulse patten fo the MOSFET nvete, wheeas the contolle of the commecal dve has been fully dsabled. In ode to mpove the accuacy of cuent measuement, an analog band-pass flte has been mplemented fo the extacton of the hgh fequency cuents njected n two of the moto phases. Ths soluton allows the sepaate and ndependent condtonng and samplng of both the nstantaneous cuents and the espectve hgh fequency cuents on two couple of channels (+), wth optmzed scalng fo each couple. The MOSFET nvete s fed though an extenal DC powe supply at the ated voltage of 48 V. Beng the commecal moto fo cty scoote equpped wth poston sensos (both Hall sensos and an ncemental encode atng 64 pulses pe mechancal ound), the elated sgnals have been also ntefaced wth the EVM boad to acheve the measuement of the actual oto poston and calculate the poston estmaton eo. Due to the (elatvely) low esoluton of the encode, although quadupled by the DSP quadatue encode unt, the pecson n the measuement of the electcal poston s n the ode of 3 degees. The basc paametes of the DSP mplementaton and sgnal njecton ae depcted n TABLE II. The PWM and cuent samplng peods have been set to µs, whch s the tme necessay fo the executon of the whole contol algothm (adaptve obseve, sgnal njecton, Kalman flte). The algothm nclude the cae ecovey stategy pesented n [3] fo the demodulaton of the hgh fequency cuents. Fgue 1. Expemental pototype of the dve fo cty-scoote applcaton. The expemental esults ae pesented n Fgue 11 to Fgue 16. All the tests ae caed out at no load. Fgue 11 shows the speed tansent fom to.15 p.u.. In ths ange (low speed opeaton) sgnal njecton s always actve and the elated poston estmaton s used to assst the adaptve obseve. One notces the poston eo dung the tansent, and the estmated (smooth) speed tackng the actual one, ths last affected by the nose due to the calculaton fom the low esoluton encode. The poston peak eo s n the ode of 14 degees. Fgue 1 shows the speed tansent fom.15 to.3 p.u.. In ths ange, at. p.u., thee s the tanston fom the low to the hgh speed egon: sgnal njecton s emoved, as shown by the lack of njected voltage sgnal. The nvese tanston fom hgh (.3 p.u.) to low (.15 p.u.) speed ange wth estat of the sgnal njecton s shown n the subsequent Fgue 13. Fgue 11. Speed tansent fom to.15 p.u. (nsde the low speed ange).

7 sgnal njecton, absence of not necessay losses and the avalablty of the full feedng voltage fo fundamental opeaton wth hgh speed obseve. The acheved esults demonstated the satsfactoy pefomance of the poposed system, whch has been tested on a commecal pototype fo cty scoote applcaton. The use of some smple accuacy, such as analog band pass fltes to extact the njected cuent sgnals, allows the mplementaton wth low cost, fxed pont DSP equpped wth 1 bts A/D convete. Fgue 1. Speed tansent fom.15 to.3 p.u. (wth tanston fom the low to hgh speed egon at. p.u. speed). Fgue 14. Samplng and demodulaton of the (d) eo sgnal. Fgue 13. Speed tansent fom.3 to.15 p.u. (wth tanston fom the hgh to low speed egon at. p.u.). Fgue 14 shows the dgtal demodulaton technque used to acheve the eo sgnals (18), n the case of the d- axs component. Accodng to the chosen njecton-tocontol fequency ato, eght samples of the hgh fequency cuents ae avalable fo each peod of the njecton cae, whch has poved to be the mnmum numbe of samples to assue a satsfactoy behavo of the dgtal demodulaton. Fgue 15 shows a speed eveson movng fom the hgh speed egon nea to the ated value (-.9 p.u. to.9 p.u.). In ths case the speed follows a lnea efeence tajectoy employng two seconds fo the whole eveson. The pefomance ae satsfactoly n all the speed ange ncludng zeo cossng. Fgue 15. Speed eveson fom -.9 to.9pu. Fnally, Fgue 16 shows the steady state pefomance at vey low (3 Hz) opeaton: the sne of the actual and estmated poston appea as supemposed. VI. CONCLUSIONS. Ths pape pesents an appoach to speed sensoless contol of IPM motos based on an adaptve obseve fo hgh speed opeaton and a modfed hgh fequency sgnal njecton technque fo standstll/low speed opeaton. The mxed soluton allows to mege the advantages of both methods,.e. safe standstll and stat-up opeaton wth Fgue 16. Sne of the actual and estmated poston at low speed opeaton (3 Hz).

8 TABLE I. MOTOR PARAMETERS. Rated/base speed: 3 pm Rated/base cuent: 5 A ms Rated powe: 1.8 kw Pole pas: ω 1 Rvel q 3 Rd Rq 1 Sgnal njecton v q v d 4 dq v α v β A/D Inteface 5 AV SVPWM Stato esstance: Dect nductance: Quadatue nductance: Back-EMF constant: I : I 1 : Aveage nductance (L): Inductance modulaton ( L):.3 mω.45 mh.8115 mh 7.5 mv ms/pm ( ) 3.8 A 1.86 A.518 mh.9 mh d = 8 v α q d θˆ Sgnal Injecton pocessng & Adaptve obseve v β a b 7 dq α β 6 a b PMSM TABLE II. INJECTION/CONTROL/SYSTEM PARAMETERS. Voltage (V s ) Fequency (f s ) PWM peod Speed of tanston fom low to hgh speed obseve Speed whee the sgnal njecton s emoved DC bus voltage 6.11 Vms 568 Hz us. pu.5 pu 48 V APPENDIX: SENSORLESS DRIVE SCHEME. The sensoless dve scheme s pesented n Fgue 17. It efes to a fully-dgtal mplementaton employng fxedpont dgtal sgnal pocesso. The feld-oented contolle s based on a cuent-contolled voltage souce nvete stuctue. The cuent contol loops ae aanged n the twophase synchonously otatng efeence fame d-q algned wth the oto magnet flux. Popotonal and ntegal egulatos ae used fo both the cuent and speed contol loops. An adjacent-vecto space vecto pulse wdth modulato (AV-SVPWM) s used to apply the voltage commands. The adaptve obseve estmates the oto magnet flux angle θˆ (needed fo the feld oentaton) and the oto speed feedback (used fo the speed contol loop). Hgh fequency voltage sgnals ae supemposed to the d-q voltage commands dung low speed and standstll opeaton. The esultng hgh fequency cuent components ae pocessed by a heteodynng technque that poduces an nfomaton on the oto magnet poston. Ths sgnal s used to tune the adaptve obseve n such ctcal opeaton condtons. Fgue 17. Sensoless dve scheme. REFERENCES [1] F. Paaslt, R. Petella and M. Tusn, Sensoless Contol of Bued PM Synchonous Motos, n Poc. of the Thteenth Inteactve Semna, Vol., pp , Bessanone (Italy), Mach 18- (n Italan). [] F. Paaslt, R. Petella, M. Tusn, Sensoless Speed Contol of Salent Roto PM Synchonous Moto Based on Hgh Fequency Sgnal Injecton and Kalman Flte, n Poc. of the ISIE Conf., CD ROM, L Aqula (Italy), July. [3] F. Paaslt, R. Petella and M. Tusn, Speed Sensoless Contol of an Inteo PM Synchonous Moto, Poc. of the Thty Seventh IEEE-IAS Annual Meetng, CD ROM, Pttsbugh, Octobe 13-17,. [4] N. Banch, S. Bolognan, M. Zglotto, Hgh-Pefomance PM Synchonous Moto Dve fo an Electcal Scoote, IEEE Tans. Ind. Applcatons, Vol. 37, No. 5, pp , Septembe/Octobe 1. [5] Ph.K. Sattle and K. Stäke, Estmaton of speed and pole poston of an nvete fed pemanent excted synchonous machne, n Poc. of the EPE Conf., pp , Aachen, [6] L.A. Jones and J.H. Lang, A state obseve fo the pemanent magnet synchonous moto, IEEE Tans. Ind. Electoncs, Vol. 36, No. 3, pp , August [7] F. Paaslt, R. Petella and M. Tusn, Sensoless speed contol of a PM synchonous moto based on sldng mode obseve and extended Kalman flte, Poc. of the Thty Sxth IEEE-IAS Annual Meetng, CD ROM, Chcago, Septembe 3 Octobe 4, 1. [8] S. Bolognan, R. Oboe and M. Zglotto, Sensoless full-dgtal PMSM dve wth EKF estmaton of speed and oto poston, IEEE Tans. on Industal Electoncs, Vol. 46, No. 1, pp , Febuay [9] N. Matsu, Sensoless PM bushless dc moto dves, IEEE Tans. on Industy Applcatons, Vol. 43, pp. 3-38, Apl [1] M.J. Coley and R.D. Loenz, Roto poston and velocty estmaton fo a salent pole pemanent magnet synchonous machne at standstll and hgh speeds, IEEE Tans. on Industy Applcatons, Vol. 34, No. 4, pp , July/August [11] M. Shoedl, Sensoless contol of AC machnes at low speed and standstll based on the INFORM method, n Poc. of the Industy Applcaton Socety Annual Meetng, Vol. 1, pp. 7-77, [1] A. Consol, G. Scacella and A. Testa, Sensoless contol of PM synchonous motos at zeo speed, n Poc. of the Industy Applcaton Socety Annual Meetng, Vol. 1, pp. 7-77, [13] A. Belln, S. Bfaett and S. Costantn, Identfcaton of the mechancal paametes n hgh-pefomance dves, n Poc. of the EPE Conf., CD ROM, Gatz, 1.