A COMPARATIVE ANALYSIS OF THE EFFECTS OF ROTOR MOLDING. CLINCHES ON TORQUE RIPPLE OF MUTUALLY COUPLED SRMs

Transcription

1 Interntionl Review of Electricl Engineering (I.R.E.E.), Vol. A COPARAIVE ANALYSIS OF HE EFFECS OF ROOR OLDING CLINCHES ON ORQUE RIPPLE OF UUALLY COUPLED SRs C. Shin, A. E. Amc,. Krcor 3, nd A. Emdi 4 Abstrct In this study, the mitigtion of torque ripples t mutully coupled switched reluctnce motor (CSR) is investigted experimentlly. Although, CSRs hve higher performnce thn clssicl switched reluctnce mchines (SRs), they re not ttrctive enough due to their high torque ripples. here re mny different methods to solve this problem. One of the methods is to chnge the geometric structure of the mchine. he nlyses of previous studies show tht despite there being fvorble results in pplictions, the molding pins of the mchines re neglected in those works. A motor tht gives positive results my get ffected negtively by its rndom molding during genertion. In this reserch, 3-phse verge wtt CSR is chosen for nlysis nd effects on torque of the geometric point of molding pins in the mchine re studied comprtively. xwell D progrm is used for nlyses nd two different models re compred with ech other. he obtined results show tht torque ripple of the mchine is lower when molding pins re closer to the rotor post, nd it is reduced by % t 6 Amps in the proposed CSR. Keywords: Short pitched, full pitched, SR, orque ripple, CSR i i i b c List of symbols = current in winding A = current in winding B = current in winding C L = self inductnce of winding A L = self inductnce of winding B b L = self inductnce of winding C L c l b bc c = lekge inductnce = mutul inductnce between winding AB = mutul inductnce between winding BC = mutul inductnce between winding CA = torque N = number of turns per phse α = mchine xil length G = ir-gp length β = length of overlp between rotor nd sttor teeth = mgnetic-flux linkge ψ r = rotor position = rdius β r = rotor pole rc (degree) β = sttor pole rc (degree) s t = sttor pole width t s r = rotor pole width d = sttor pole height s d = rotor pole height r y = sttor yoke thickness s y = rotor yoke thickness r I. Introduction ody, high speed motor drives re widely used in industril res s well s in home pplinces such s ir conditioners, suction sweeper, compressors etc. due to their high power cpbility nd compct dimensions. For high speed pplictions, permnent mgnet (P) or induction mchine (I) hve been overly studied, but clssicl SRs hve some dvntges over P or I, such s simple nd strong mechnicl construction. oreover, they do not need rotor winding or permnent nuscript received y, revised y Copyright 7 Prise Worthy Prize S.r.l. - All rights reserved

2 mgnet. Although P mchines re preferred for specific pplictions, they re not cost effective for mss production []. However, SRs hve robust performnce for intense circumstnces, nd high temperture long with high speed ppliction nd low mnufcturing cost []. hey lso offer high efficiency nd long stble power region with durble structure [3]. Even though the first SR ws produced in 838, they were not used in industries until the lte 97s becuse of their control problems. he min disdvntges of SRs re their being switched electroniclly nd not supplying directly from AC or DC source [4]. he development of power electronics nd semiconductor switches during the 96s simplified the control of SRs, nd SR drives begn to ttrct greter ttention [5]. In order to increse the output power, SR drives re employed in sturtion. Flux linkge, inductnce, bck emf, nd phse torque in SR model re considerbly nonliner functions of both rotor position () nd phse current (i) becuse of mgnetic reluctnce vrition nd sturtion effect. A combintion of the non-liner coupling between rotor position nd mchine design lso cuses this nonlinerity. Hence, SRs need complex control lgorithms in spite of their simple mechnicl structures. High torque ripple nd coustic noise re other drwbcks of these mchines [6, 7]. In order to reduce the torque ripple of SRs, reserchers hve proposed two pproches in literture: improving the motor mgnetic design nd using complex control scheme for the mchine. Achievement of the control method depends on selecting n optimum combintion of operting prmeters like supply voltge, turn-on turn-off ngles of switches, nd current level, which is highly troublesome [8]. Afterwrd, SR designers proposed chnging the sttor nd rotor pole structures to mitigte moment ripple. Nevertheless, these modifictions bdly ffected the mchine performnce. While previous studies mostly relied on current control strtegies to minimize torque ripple, ecrow proposed simple structurl modifictions on SR to increse the torque performnce. ecrow chnged the windings structure of clssicl SR nd plced windings s full pitched insted of short pitched. He clled the mchine Full Pitched SR or utully Coupled Switched Reluctnce chine (CSR). Although the performnce of the proposed mchine incresed, its complex control lgorithm cused limittions in utiliztion. On the other hnd, developed control lgorithms hve llowed designers esier control of SCR since the lst decde. However, torque ripple is still significnt problem in the mchine. In this study, while rotor nd sttor pole hed re the sme, ltering the position of the molding clinches of SCR is suggested s the solution. Lter, the torque ripples of the modified mchine models re studied. he torque ripples of the proposed mchine models decrese between 3% nd 7% t different current levels depending on the distnce of the rotor molding clinches from the pole hed. II. Structurl Comprison Between Clssicl SR nd CSR he only difference between SRs nd the clssicl mchine is tht SRs hve notches tht crete sttor nd rotor poles. Rotor nd sttor re mde of pckge of iron pltes, which hve high mgnetic qulity, nd thickness between.5 nd.35 mm. Windings re locted t sttor poles nd there re no windings in the rotor, which is n importnt dvntge in terms of losses. he pole number of SR is determined s some criteri like torque cpbility, torque ripple, nd four qudrnts running. It is common knowledge tht incresing the pole number decreses the torque ripple t SR. he phse number of SR is different from the phse number of trditionl electricl mchine. Every sttor pole crries excittion winding nd connects in series with the opponent sttor pole. hese two sttor poles crete phse for the mchine. he number of sttor poles in SR is proportionl to the phse number. When the number of sttor poles is incresed, the phse number lso increses. SRs produce torque ccording to the reluctnce of the mchine. Reluctnce nd inductnce t SRs led to the estblishment of flux, nd therefore, rottionl motion [9]. Reluctnce depends on the ir-gp between rotor nd sttor in SRs. When suitble phse in the mchine is excited with DC voltge, rotor moves in the direction of reducing the circuit reluctnce. Continuity in turning of rotor is obtined by the excittion of windings []. Fig. shows the generl structure of clssicl SRs. Fig.. Clssicl SR In contrst, designers hve creted CSRs through ltering the windings of clssicl SR. his novel winding structure hs gined different extensions by ecrow s studies regrding incresing of SRs performnce. ecrow hs mde simple modifictions in Copyright 7 Prise Worthy Prize S.r.l. - All rights reserved

3 the windings of the mchine without using dditionl windings. hese bsic innovtions hve incresed the positive torque production of the mchine. In CSR, torque is produced by the chnging of the mutul couple tht occurs between phses ccording to rotor position. CSR hs 5% more verge torque thn clssicl SR []. Fig. shows the structure of CSR. CSR is produced bsed on mutul inductnce, which is obtined by the effect of ctive phses on ech other, s cn be seen in (4) [4]. b + ibi bc + ici c = iib c Since two phses re ctive in CSR (ssume phse nd phse b re ctive, nd phse c is pssive), (4) turns into (5). (4) b = iib (5) While every phse contributes to torque production t the rte of /3 in 3-phse clssicl SR, this rtio increses to /3 in CSR [5]. hus, the electricl circuit in CRS is utilized twice compred to clssicl SR. Fig.. utul coupled SR Ech sttor phse, controlled independently, genertes totl torque in SR. hus, torque production is trnsferred from one ctive phse to nother by turn. Consequently, torque pulstions re the most importnt thing in these commuttion moments []. Eqn. gives the generl torque expression in 3-phse clssicl SR [3]. i i b L Lb = i + ib + ic b bc c + ibic + ici Lc + Where is the totl torque; i, i b, i c re the phse currents; L, L b, L c re the phse inductnces; nd b, bc, c re the mutul inductnces between the phses. he lst three terms re neglected since they re usully considered negligible in clssicl SRs. Eventully, torque in clssicl SRs is produced by the selfinductnce of their ctive phse ccording to (). () orque ripple is the most importnt issue for both SR nd CSR. In order to clculte the torque ripple, instntneous torque nd verge torque should be defined. he instntneous torque is clculted for SR nd CSR from (3) nd (5) respectively. he verge torque cn be derived mthemticlly through integrtion. vg = inst. dt. he verge torque is very importnt nd criticl prmeter for both users nd designers. he difference between the mximum nd minimum instntneous torque expressed s percentge of verge torque t stedy-stte opertion is clled torque ripple [6, 7]. ins (mx) ins (min) orque ripple = x% vg Assume tht the self-inductnce of ech winding in clssicl SR hs constnt lekge vlue s shown in (8). (6) (7) = i L + i b Lb + i c Lc () L phse N αβ L = Ll + µ (8) G If it is ssumed tht only phse is ctive, () simplifies s (3) for clssicl SRs. = i L As result, it cn be sid tht the electricl circuit of the mchine is less utilized in clssicl SRs. he torque in Copyright 7 Prise Worthy Prize S.r.l. - All rights reserved (3) where L phse is the totl self-inductnce of phse, L l is the lekge inductnce per phse, N is the number of turns per phse, α is the mchine xil length, G is the ir-gp length, nd β L is the length of overlp between rotor nd sttor teeth.

4 utul inductnce between phses should be determined for CSR nd clculted using (9). gps, insted of being directly clinched to pole legs, for obtining full step [9]. b N αβ = µ (9) G Where β is the dimension (x - y) s shown Fig. 3 nd cn be clculted from () nd (). Fig. 3. Overlpped tooth length for pproximte self nd mutul inductnce. β = x y () L + β = x y () orque produced by the mchine is directly proportionl to flux. Fig. 4 shows modl comprison of the fluxes t clssicl SR nd CSR. It cn be seen tht CSR hs qudrupled the ctive phse flux compred to clssicl SR though both work t equl currents. Consequently, CSR hs doubled the flux production in proportion to clssicl SR for equl copper loss. Nevertheless, incresing of torque production in CSR is limited between -3% becuse of the mgnetic sturtion [8]. ψ ψ lg Fig. 5. ) Structure of SCR, b) 3-dimensionl form of CSR III. Design Considertions of CSR here re three different excittion methods for CSR, nd the produced nd verge torque of CSR chnge ccording to these methods. In this study, unidirectionl excittion method is pplied. he mutul inductnce profile of the mchine, which hs 6/4 poles nd 3 step ngle, is given in Fig. 6. From the figure, it cn esily be seen tht the period of the three-phse mchine is 9. Idelized profile of mutul inductnce cuses linerity in grphics s shown in Fig. 6. he mutul inductnce of the mchine hs three chrcteristics. It shows incresing tendency for the first 3, decresing tendency for the second 3, nd constnt tendency for the third 3. Phses re in conduction in /3 period t unidirectionl excittion, nd this is 6 in 6/4 3-phse CSR. ψ ψ ψ lg unlg ψ unlg () I fz (b) I fz Fig. 4. ) Flux production in clssicl SR, b) Flux production in CSR Fig. 5 shows the structure nd 3-dimensionl form of CSR. Phse windings in CSR re locted in pole Copyright 7 Prise Worthy Prize S.r.l. - All rights reserved

5 b ts bc tr r 3 r yr ys c r r β r β s ds I I b I c 6 8 Rotor position Fig. 6. utul inductnce nd current chrcteristics of unidirectionl excited CSR Phse switching nd chnging nonliner reluctnce cuse torque ripples in CSR. Different control methods nd vrious mchines hving different geometric structures hve been developed to solve the problem. J. Y. Lee creted mgnetic brriers using novel design on the rotor pltes of clssicl SR. he mgnetic brriers cuse more sturtion for rotor poles; therefore, the inductnce profile of the mchine degrdes bdly. As result, chnging of inductnce immeditely influences torque chrcteristics []. Similrly, torque is effected either positively or negtively even with smll chnges in the geometric structure of CSR. herefore, combining of the pltes, which constitute sttor nd rotor in the mchine, is n importnt issue in the design []. A w, 6/4 CSR is proposed for observtion nd elimintion of torque ripple in this study. tlb GUI Bsed SR Design Progrm is employed for finding the generl dimensions of the mchine. wo different mchine models with mounting merging pprtus t two different plces on the rotor in the mchine re cquired. Ech of the obtined motor models is nlyzed t different currents thorough Finite Element ethod. he nlysis results of the two models re compred with ech other t smple current. It is find tht the gin is within cceptble rnge nd the torque ripple is decresed in the proposed model. Fig. 7 shows the geometric structure of the proposed mchine. ble presents the dimensions of w, 6/4 CSR. Fig. 7. he proposed CSR ABLE I GEOERIC DIENSIONS OF HE PROPOSED CSR Symbol Vlue (m) Symbol Vlue (m) r 8.75 x -3 y s 3. x -3 r 4.5 x -3 y r 5.75 x -3 r 37. x -3 d s. x -3 r 3 5. x -3 d r 5.75 x -3 t s 3.5 x -3 β r 3 t r 3.5 x -3 β s 3 g.5 x -3 IV. Results nd Discussions In order to obtin rel results, the molding clinches re locted on sttor nd rotor in the mchines, nd defined in the nlysis progrm. he chnnels plced winding covers re lso determined. Fig. 8 shows the proposed odel-. Rotor molding clinches re locted t plce tht is close to the rotor shft nd fr from the rotor pole hed. Copyright 7 Prise Worthy Prize S.r.l. - All rights reserved

6 sttor molding clinches screw chnnels of motor cover A B C C rotor molding clinches B A Fig.. Flux distribution for odel- t 6 mps Fig. 8. Rotor molding clinches close to rotor shft (odel-), mx he xwelld progrm is used for nlyzing odel-. he curves of flux, mutul inductnce, nd torque re plotted for the model s shown in Fig. 9. orque (Nm),8,6,4, = %5 d min orque (Nm) utul Inductnce (H),5,5, ,5,5,,5 -, , -,5 -, -,5 -,3 APER APER 3 APER 4 APER 5 APER 6 APER 8 APER APER APER APER 3 APER 4 APER 5 APER 6 APER 8 APER APER , Fig.. he torque curves of odel- t 6 mps Fig. shows the torque curve of the proposed odel- t 6 mps. For clcultion of torque ripple, the instntneous torque nd verge torque re found. Obtined vlues t 6 mps re replced in (7) nd s result, torque ripple of the proposed odel- is 5%. Proposed odel- is obtined through n optimiztion study on odel-. he sme sttor is used in odel- nd only simple modifiction is mde on its rotor. It is presented in Fig.. Rotor molding clinches re locted close to the rotor pole hed in this configurtion. hey re plced 4.5 mm bove the previous one. Flux (Wb),8,6,4,,,8,6,4, APER APER 3 APER 4 APER 5 APER 6 APER 8 APER APER clinches A B Fig. 9. Curves of torque, mutul inductnce, nd flux respectively for odel- C C Distribution of the flux for odel- t 6 Amps is shown in Fig.. B A clinches Fig.. Rotor molding clinches close to rotor pole hed (odel-) Copyright 7 Prise Worthy Prize S.r.l. - All rights reserved

7 odel- is lso nlyzed with xwelld; the curves of flux, mutul inductnce, nd torque re drwn for the proposed model. Fig. 3 shows the curves of torque, flux, nd mutul inductnce for the odel-. orque (Nm),,8,6,4, = %39 d Flux (Wb) utul Inductnce (H) orque (Nm),5,5, ,5,5,,5 -, , -,5 -, -,5 -,3,8,6,4,,,8,6,4, APER APER 3 APER 4 APER 5 APER 6 APER 8 APER APER APER APER 3 APER 4 APER 5 APER 6 APER 8 APER APER APER APER 3 APER 4 APER 5 APER 6 APER 8 APER APER , Fig. 5. orque curves of odel- t 6 mps Fig. 5 shows the torque curve of the proposed odel- t 6 mps. For clcultion of torque ripple, the instntneous torque nd the verge torque re found. he obtined vlues t 6 mps re replced in (7) nd the torque ripple of the proposed odel- is clculted s 39%. Proposed odel- nd odel- re nlyzed in the rnge of - mps with mp steps. odel nd odel hve exctly the sme sttor structure. Reserchers only modify the plces of rotor clinches. Dimensions between the clinch points re shown in Fig.6. he distnce between the centers of the clinches is 4.5 mm. Fig. 3. Curves of torque, mutul inductnce, nd flux for odel- respectively Fig. 4 shows the distribution of flux for odel- t 6 mps. Fig. 6. Comprison of the distnce between clinch centers For the comprison of torque ripple, the curves obtined t 6 mps re drwn for odel- nd odel-. orque curves, flux distributions, nd plte cuttings of odel- nd odel- re given in Figs. 7, 8 nd 9 respectively., orque (Nm),8,6,4, ODEL- ODEL- ODEL- ODEL , Fig. 7. Comprisons of the curves of torque ripple for odel- nd odel- Fig. 4. Flux distribution for odel- t 6 mps Copyright 7 Prise Worthy Prize S.r.l. - All rights reserved

8 mentioned in previous works. It is comprehensively covered in this study for improvement of torque ripple in CSR. ble shows the chrcteristics of odel- nd odel- for different currents. Correction of torque ripple increses while operting current goes up. ABLE II. CHARACERISICS OF ODEL- AND ODEL- FOR DIFFEREN CURRENS Current (A) odel- ( d ) odel- ( d ) Correction of orque Ripple (%) ) odel- b) odel- Fig. 8. Flux distributions for odel- nd odel-. V. Conclusion In this study, simple suggestion is mde towrds the reduction of torque ripple in CSR. he geometric structure of the mchine is not chnged. he position of molding clinches in CSR is ltered with the im of emphsizing its effect on torque ripple. wo CSR models re constituted for the exmintion. he molding clinches re plced closer to the rotor shft in odel- nd torque ripples re investigted for different operting currents. he plce of molding clinches in odel- is shifted towrds the rotor pole hed. orque ripples of odel- nd odel- in different currents re compred. It is observed tht if the molding clinches re closer to the rotor pole hed, torque ripple of CSR decreses. As result, the position of rotor molding clinches in CSR, which is highly neglected in previous studies, hs gret effect on its performnce. Hence, the designing of CSR with correct position of molding clinches is very importnt for its torque ripple nd should be tken into ccount for future designs nd studies. References Fig. 9. Rotor pltes for odel- nd odel- Consequently, vlues of the torque peks re not much chnged between odel- nd odel-. However, there re distortions in the torque curve t dropping instnce in odel-. On the other hnd, this dropping is not importnt in cse of torque continuity. While the torque ripple is 5% in odel-, it decreses to 39% in odel-. hus, there is % reduction in torque ripple when clinches re brought closer to the rotor pole hed. he enhncement is chieved by only one simple modifiction of the clinches. Although molding fctor is n importnt issue during the modifiction of pole heds, it is not Copyright 7 Prise Worthy Prize S.r.l. - All rights reserved []. S. Chung, Acoustic Noise Reduction of 6/4 SR Drive Bsed on hird Hrmonic Rel Power Cncelltion nd utul Coupling Flux Enhncement", Energy Conversion nd ngement, vol. 5, no. 3, rch, pp [] K. Ahn,. K. Huynh, D. H. Lee, Design nd nlysis of high speed 4/ SRs for n ir-blower, in Proc. IEEE Interntionl Symposium on INDUSRIAL ELECRONICS, ~ISIE ~, July 4-7,, Bri, Itly. [3] B. Fhimi, A. Emdi, B. R. Sepe, A Switched Reluctnce chine- Bsed Strter/Alterntor for ore Electric Crs, IEEE rnsctions on Energy Conversion, vol. 9, n., rch 4, pp [4]. Unlu, Simultion nd dynmic chrcteristics of switched reluctnce mchine, ster thesis, Dept. Elect. Eng., Koceli Univ., Koceli, 6.

9 C. Shin, A. E. Amc,. Krcor, A. Emdi [5] N. Ydlplli, Implementtion of novel soft switching inverter for switched reluctnce motor drivers, ster thesis, Dept. Elect. Eng., Virgini Polytechnic Institute nd Stte Univ., Blcksburg, VA, 999. [8] X.i Yunto, Utility interfce design nd mutul coupled switched reluctnce mchine study for wind genertion system, PhD. Disserttion, Dept. Elect. Eng., Rensseler Polytechnic Institute, roy, NY,. [6] E. Drybeigi, Gh. A rkdeh, C. Lucs, A. Askri, Switched reluctnce motor (SR) control, with the developed brin emotionl lerning bsed intelligent controller (BELBIC), considering torque ripple reduction, in Proc. IEEE Electric chines nd Drives Conference ~IEDC 9~, y 3-6, 9, imi, USA. [9] K. Yılmz, orque improvement of switched reluctnce motor using new winding configurtion, PhD. Disserttion, Dept. Elect. Edu., Koceli Univ., Koceli, 4. [7] P. C. Desi,. Krishnmurthy, N. Schofield, A. Emdi, Design nd performnce evlution of novel 6/ switched reluctnce mchine, in Proc. IEEE Electric chines nd Drives Conference ~IEDC 9~, y 3-6, 9, imi, USA. [8] F. Dldbn, N. Ustkoyuncu, ultilyer Switched Reluctnce otor to Reduce orque Ripple, Energy Conversion nd ngement, vol. 49, no. 5, y 8, pp [9] P. C. Desi,. Krishnmurthy, N. Schofield, A. Emdi, Switched reluctnce mchines with rotor poles higher thn sttor poles for improved output torque chrcteristics, in Proc. 35th Annul IEEE Industril Electronics Conference ~IECON 9~, November 3-5, 9, Porto, Portugl. []. Grip, Y. Ozoglu, E. ese, An pproch to torque ripple reduction in fully pitched switched reluctnce motors by pole tip shping, in Proc. th Annul IEEE editerrnen Electrotechnicl Conference, ~ELECON ~, y 7-9,, Ciro, EGYP. [] B. G. ecrow, Fully Pitched-Winding Switched-Reluctnce nd Stepping-otor Arrngements, IEE Proceedings-B, vol. 4, no., Jnury 993, pp [] Y. H. Kim, S. Kimb, J. H. Choic, J. Ahnd, C. H. Choe, J. Lee, Direct orque Control of Switched Reluctnce otor for inimizing orque Ripple, Interntionl Journl of Applied Electromgnetics nd echnics, vol. 8, no. -, September 8, pp [3] Y. Ozoglu,. Grip, E. ese, New Pole ip Shpes itigting orque Ripple in Short Pitched nd Fully Pitched Switched Reluctnce otors, Electric Power Systems Reserch, vol. 74, no., April 5, pp [4] G. Gllegos-Lopez, R.J. Kreft, Comprison of full pitch nd concentrted coil switched reluctnce mchines, in Proc. 38th IAS Annul eeting Industry Applictions Conference, ~IAS 3~, October -6, 3, Slt Lke City, USA. [5] K. Yılmz, E. eşe, Comprison Between Short-Pitched nd Unipolr Excited Fully-Pitched Switched Reluctnce otors for Equl Electricl Losses, he Arbin Journl for Science nd Engineering, vol. 33, no. B, rch 8, pp [6] Sheikhi, A., Oree, H., Kboli, S., nd Dorkhh,., "A new configurtion of switched reluctnce motor for reducing the torque ripple", in Proc. IEEE Interntionl Conference on ELECRIC POWER nd ENERGY CONVERSION SYSES, ~EPECS 9~, November -, 9, Shrjh, UAE. [7] P. C. Desi,. Krishnmurthy, N. Schofield, A. Emdi, Novel Switched Reluctnce chine Configurtion with Higher Number of Rotor Poles thn Sttor Poles: Concept to Implementtion, IEEE rnsctions on Industril Electronics, vol. 57, no., Februry, pp Copyright 7 Prise Worthy Prize S.r.l. - All rights reserved [] J.Y. Lee, G.H. Lee, J.P. Hong, J. Hur, Y.K. Kim, Coupled Field Circuit Anlysis for Chrcteristic Comprison in Brrier ype Switched Reluctnce otor, KIEE Interntionl rnsctions on Electricl chinery nd Energy Conversion Systems, vol. 5-B, no. 3, August 5, pp [] Kuyumcu, F. E., Krçor,., "tlb GUI bsed SR design progrm", in Proc. IEEE Interntionl Aegen Conference on ELECRICAL ACHINES nd POWER ELECRONICS nd ELECROOION JOIN CONFERENCE, ~ACEP 7~, September -, 7, Bodrum, urkey. Kstmonu University, osy, Kstmonu, urkey, el: , Fx: , Koceli University, Deprtment of Electricl Eduction, 438, Koceli, urkey, el: , Fx: cster University, Deprtment of echnicl Engineering, John Hodgins Engineering Building, Ontrio, L8S4L7, Cnd, Voice: x73, Fx: E-mils: cihnshin98@yhoo.com, yseergun@koceli.edu.tr, mkrcor@koceli.edu.tr, emdi@mcmster.c C. Shin (S 7) re received his B.S. nd.s. degrees in Electricl Eduction from Koceli University, Koceli, urkey, in 4 nd 7 respectively. He is currently Ph.D. cndidte in Electricl Eduction of echnicl Eduction Fculty in Koceli University. His reserch interests re utomtion systems (PLC, SCADA, etc ), power electronics nd engineering eduction. A. E. Amc (S 97-3) received the B.S. degree (with honors) in electricl eduction from rmr University, Istnbul, urkey in 994 nd the.s. nd the Ph.D. degrees in electricl eduction from Koceli University, Koceli, urkey in 997 nd 3 respectively. From 995 to 3, she ws reserch nd teching ssistnt in Deprtment of Electricl Eduction, in Koceli University, echnicl Eduction Fculty. From to 4, she ws in the Electric nd Power Electronics Center nd the Gringer Lbortories, Illinois Institute of echnology, Chicgo s reserch scholr to study on ctive filters nd uninterruptible power supplies. Since 4, she hs been with the Deprtment of Electricl Eduction, Koceli University, echnicl Eduction Fculty, Koceli, s n Assistnt Professor. Dr. Amc s current reserch interests re hybrid electricl vehicles nd computer bsed lerning pproches in teching power electronics courses.. Krcor (S 4- ) received his.s. nd the Ph.D. degrees in electricl eduction from Koceli University, Koceli, urkey in 4 nd respectively. Since 999, he hs been working s n reserch nd teching ssistnt in Deprtment of Electricl Eduction, in echnicl Eduction Fculty, Koceli University. His reserch interests re

10 utomtion systems (PLC, SCADA, etc ), power electronics nd engineering eduction. A. Emdi (S 98- -S 3) received the B.S. nd. S. degrees in electricl engineering with the highest distinction from Shrif University of echnology, ehrn, Irn, nd the Ph.D. degree in electricl engineering from exs A& University, College Sttion. He is the Hrris Perlstein Endowed Chir Professor of electricl engineering nd the Director of the Electric Power nd Power Electronics Center nd the Gringer Lbortories, Illinois Institute of echnology, Chicgo, where he hs estblished reserch nd teching fcilities in ower electronics, motor drives, nd vehiculr power systems. He is the principle uthor/couthor of over journl nd conference ppers, s well s six books. Dr. Emdi ws the founding Generl Chir of the st IEEE Vehicle Power nd Propulsion Conference (VPPC 5) nd is currently the Chir of the IEEE VPPC Steering Committee. He hs been nmed s Chicgo tters Globl Visionry in 9. He is currently the Cnd Excellence Reserch Chir (CERC) in Hybrid Powertrin nd Director of cster Institute for Automotive Reserch nd echnology (cauo) t cster University in Hmilton, Ontrio, Cnd. Copyright 7 Prise Worthy Prize S.r.l. - All rights reserved