Modeling and Dynamics Characteristics Analysis of a Linear Oscillating Motor

Transcription

1 Intrnational Journal of Elctronic and Elctrical Enginring Vol. 5, No. 3, Jun 7 Modling and Dynaic Charactritic Analyi of a Linar Ocillating Motor Huihng Liang DFH Satllit Co. Ltd, Bijing, China Eail: @63.co Abtract Thi papr invtigat a novl linar ocillating otor for th application of linarly drivn hydraulic pup. Th otor oring principl and pcial tructur a laboratd. It ti-doain, frquncy-doain and vctor dynaic odl ar tablihd rpctivly. And bad on th odl, th otor ronant frquncy charactritic i analyzd. In addition, th influnc of dynaic paratr on th ronant frquncy charactritic i invtd. A ronant capacitor i connctd to th coil to copnat th inding inductanc, and th otor por factor and chanical charactritic i rarchd. At lat, th otor por pctru i acquird to contribut to th dynaic paratr dign and optiization. Indx Tr linar ocillating otor, dynaic odl, ronant frquncy, por factor I. INTRODUCTION Linar Ocillating Motor (LOM) could provid horttro rciprocat otion ith high fficincy, and ar bing ployd incraingly in any application, uch a vibrator, fluid pup, artificial hart dvic, hybrid lctric vhicl, and copror, tc. Particular xapl includ tirling cycl cryognic coolr for atllit rot ning yt and linar copror for rfrigrant and air conditioning []. In th indutry application, intad of traditional rotary otor oprating od, th linar ocillating otor provid thrut forc dirctly to pay load ithout rotary-to-linar countrpart uch a cr, gar, and cran, o th abnc of th chanical countrpart bring in any ignificant advantag including iplicity, fficincy, dynaic prforanc, rliability and lifpan, tc. Th opration od of LOM i to driv th actuator at a chanical ronant frquncy in ordr to a th linar actuator not only raliz all iz and por input, but alo achiv optiu fficincy and vlocity. Gnrally, th rarch of linar ocillating otor can b dividd into thr typ []: oving-iron, ovingcoil and oving agnt otor. Th oving-iron otor confor to th principl of agntic rluctanc. Th coil ar tator, hil lottd iron tub i th ovr. Whn th coil ar nrgizd, th ovr i actuatd undr th attractiv forc of rluctanc. Th oving iron typ can produc high thrut. But it larg inrtia ay cau lo dynaic prforanc. Moving-coil otor i bad II. CONCEPT DESIGN AND OPERATING PRINCIPLE Th oprating principl of linar ocillating otor i illutratd in Fig.. Magntic flux flo through tator cor, air-gap, PM and ovr cor in turn, and for a clod loop. Enrgizing inding on th tator produc N and S pol at corrponding tator tth. Th intraction btn agntic fild of tator and ovr gnrat th lctroagntic forc and ov th ovr in th axial dirction. By varying th currnt input in th coil priodically, rciprocating otion ar achivd ith controllabl frquncy and aplitud. Multipl prannt agnt (PM) pol and lctroagntic (EM) pol ar ployd to rduc flux laag and gnrat high thrut output. Figur. Magntic circuit oring principl. Du to th rciprocating otion charactritic of high frquncy hort tro, th dignd otor nd to Manucript rcivd April 6, 7; rvid Jun 3, 7. 7 Int. J. Elctron. Elctr. Eng. doi:.878/ij on th principl of Lorntz forc [3]. Th oving coil typ ha all ovr a and high dynaic, but at anhil, it thrut i rlativ allr du to it larg quivalnt air gap. So, in ordr to ithr achiv larg forc output or th rlativ highr ronant frquncy, th oving agnt otor ha rcivd or intrt rcntly, du to thir inhrnt high por dnity and high fficincy [4]. Th purpo of thi papr i to dvlop a tubular prannt-agnt linar ocillating otor ith larg thrut and high dynaic prforanc for th application of a ind of linarly drivn hydraulic pup. Thi papr i organizd a follo. Sction II prnt th dign concpt and tructur of LOM. In Sction III, dynaic odl for LOM i t up by th ti-doain, frquncydoain and vctor analyi. Sction IV invt th influnc of dynaic paratr on th ronant frquncy charactritic. Finally, concluion i ad in Sction V. 3

2 Intrnational Journal of Elctronic and Elctrical Enginring Vol. 5, No. 3, Jun 7 Fp U() / R L I() F() V() X() c E() E Figur 4. Dynaic odl bloc for LOM. Bad th ti doain odling, th rlation btn conud currnt and xcitd frquncy could b acquird, hich i hon a in Fig. 5. Currnt A ploy pring to balanc th ovr inrtia forc. Thu, th otor can b n a a a-pring ronant yt. Whn th otor or, it nd to gnrat th inuoidal diplacnt output at th chanical ronanc frquncy to iprov th yt fficincy. Bad on th abov oring principl, a novl LOM i dignd and it chatic tructur i illutratd in Fig.. Th tator i ad of ild tl to incra flux dnity in th air-gap. Coil ar ound on ight tator lot. Th ovr i a hollo iron cylindr copod of quaihalbach PM array. Th flux dnity in th air-gap can b nhancd to incra th thrut, hra it i and on th othr id du to th lf-hilding ffct of quaihalbach array. Th lf-hilding ffct alo allo th dign of hollo tructur for intallation of pring and baring, thi not only rduc th ovr a to iprov th otor dynaic, but alo achiv or copact iz and iprov th por dnity Ti Figur 5. Ti-doain charactritic of LOM currnt at ronant tat. Whil th LOM or on th ronanc frquncy ith no xtrnal load, th conud currnt co to alot zro a th otor otion bco tady. It rval that th otor could achiv th bt fficincy hil it or at copltly ronant tat. Figur. Schatic tructur of th LOM (Sctional vi). III. B. Frquncy Doain Analyi Ba on th dynaic quation, th LOM frquncy odlling can b obtaind, and th tranfr function btn th otor vlocity and lctroagntic forc i xprd a [6]: DYNAMIC MODELLING AND SIMULATION A. Ti Doain Modling Th LOM could b n a a ingl DOF a-pringdaping ronant yt [5], a hon in Fig. 3. GV ( ) hr F ar th lctroagntic forc, and Fp,, c, and i th xtrnal load, pring tiffn, daping cofficint, and ovr a, rpctivly. At anti, th voltag quation of LOM i givn by: u ir L di KEv () Frquncy (Hz) hr K E i th bac-emf cofficint. Th dynaic odl bloc i dducd and hon in Fig Int. J. Elctron. Elctr. Eng. Vlocity(dB) () Pha(dg) And, o th dynaic quation of LOM i xprd a: dx d x (3) Th frquncy doain analyi i hon in Fig. 6. It ho that on ronant frquncy, th otor achiv th axiu pd undr th condition of otor ratd thrut. Thi rval th raon of crating chanical ronanc by introducing pring for LOM, and alo vrifi th ronant frquncy i th LOM optial oring point. Figur 3. Dynaic odl of LOM. F Fp x c V ( ) F ( ) c Figur 6. Frquncy doain charactritic of otor vlocity. 4

3 Intrnational Journal of Elctronic and Elctrical Enginring Vol. 5, No. 3, Jun 7 C. Vctor Analyi Th dynaic odl of LOM could alo b tranford into vctor xprion, a ar hon [7]: ( j j c) V F (4) ( R jl) I K V U (5) F K I (6) Th abov vctor paratr rlationhip can b xprd a in Fig. 7. X i v V ( ) I F F p Figur 7. Dynaic vctor paratr rlationhip of LOM. So, th vlocity of ovr can b xprd a: K I V c j j Fro th abov quation, th folloing rlation could b obtaind: V KI c ( ) KU c a b ( ( ) )( ) U (7) (8) v i arctan( ) (9) c hr, v, i ar th pha angl of th vlocity and currnt, rpctivly,th currnt aplitud i a hon: I a U b KKEc a R c ( ) () () By th abov quation, it could b concludd that th otor vlocity could b th axiu, and th xcitd currnt i th iniu iultanouly, hn th otor thrut xcitation frquncy t th condition. Thi i coincidd ith th abov analyi and iulation fro th ti doain and frquncy doain analyi. In addition, th output por of LOM can b dducd a folloing: P out cf f co ( c ( f ) ) F V (3) So, onc th aplitud of th otor ratd thrut i fixd, and iultanouly, hn th otor or on th ronant frquncy, it output por i th axiu. Th iulation rult i in Fig. 8. Output por(w) Frquncy(Hz) Figur 8. Rlationhip btn output por and xcitd frquncy. And th otor input por i a follo: UI Pin co (4) i So, th fficincy can b xprd a: ( j j c) V F (5) P ck out f P in R( c ( ) ) c K f f (6) Thi xprion indicat clarly that th otor fficincy i hight hn it or on th ronant frquncy [8], a hon in Fig. 9. Efficincy KEK( ) b L c ( ) () Frnquncy(Hz) Figur 9. Rlationhip btn fficincy and xcitd frquncy. 7 Int. J. Elctron. Elctr. Eng. 5

4 Intrnational Journal of Elctronic and Elctrical Enginring Vol. 5, No. 3, Jun 7 PARAMETER ANALYSIS guid u ho to dign th LOM to iprov th otor fficincy. A. Ronant Capacitor Th LOM intall th pring to iprov th chanical por factor to utiliz th otor thrut ability. Siilarly, it can iprov th lctrical por factor to a th ronant capacitor in ri of th lctrical yt [9]. Th coparion of lctrical por factor ith and ithout ronant capacitor i hon Fig.. It rval that th otor lctrical por factor could achiv th axiu valu hil th otor or at th ronant frquncy ith th ronant capacitor. Por factor Ronant frquncy (Hz) With capacitor.8 C. Coil Currnt and Avrag Spd Th rlationhip btn th otor coil currnt and avrag pd undr diffrnt xitd frquncy could rval th charactritic of th otor por output. Th LOM or on diffrnt frquncy ith no load, and th rlationhip btn th coil currnt and avrag pd i ho in Fig. 3. Whn th otor or on th diffrnt xcitd frquncy xcpt for th ronant frquncy 8.5Hz, th LOM could b n a a gnrator for half a cycl and an lctric otor for th othr half, o th hol output por of LOM i zro undr thi oprating od ith no load..6.4 Without capacitor Frnquncy Hz Figur. Coparion of por factor ith and ithout ronant capacitor. In addition, it can alo iprov th otor chanical charactritic to a th otor coil in ri of ronant capacitor. Thi can b xplaind in th folloing Fig.. Avrag pd(/) 3.3 Avrag pd / 8 Figur. Rlationhip btn ronant frquncy and fficincy. 9 Efficincy(%) IV... With capacitor 6Hz Hz 8.5Hz 4Hz 3Hz - - Without capacitor Currnt(A).8.7 Figur 3. LOM por pctru ith no load Avrag pd(/) Daping cofficint N/(/) Figur. Coparion of chanical charactritic ith and ithout ronant capacitor. Fro th coparion, th otor chanical charactritic and ovr pd tady ith ronant capacitor i bttr copard ith th on ithout ronant capacitor. 6Hz 4Hz 8.5Hz Hz 6Hz Currnt(A) B. Ronant Frquncy and Efficincy Bcau of th liitd tro and thrut, th LOM nd to hav rlativ high ronant frquncy, thu th otor ovr ha biggr otion vlocity []. Morovr, th rlativ high ronant frquncy can alo a th otor hav highr fficincy. Th rlationhip btn ronant frquncy and fficincy i ho a Fig.. It rval that th LOM ha highr fficincy hn th dignd ronant frquncy i highr. So, thi rul can 7 Int. J. Elctron. Elctr. Eng..5 Figur 4. LOM por pctru ith load. Whn th LOM or on diffrnt frquncy ith rlativ larg load, th rlationhip btn th coil currnt and avrag pd i ho in Fig. 4. Thi laborat that th otor or alot in th firt and third quadrant undr all th xcitd frquncy, and th otor thrut i ud for th load conuption, but in fact, it i not an ffctiv opration od bcau thi ho 6

5 Intrnational Journal of Elctronic and Elctrical Enginring Vol. 5, No. 3, Jun 7 that th dignd otor ha rlativ allr pring tiffn copard to th load, and do not giv th optial por output. In ordr to iprov th otor por output, th pring tiffn nd to b dignd to atch th xtrnal load, thu th otor or only in th firt and third quadrant on ronant frquncy. Hr, th otor ronant frquncy i iprovd to 5Hz fro 8.5Hz, and th rlationhip btn th coil currnt and avrag pd i ho in Fig. 5. Avrag pd(/) Hz 4Hz - 5Hz 6Hz Currnt(A) Figur 5. LOM por pctru ith incrad ronant frquncy. Fro th abov coparion, it i concludd that th otor ha bttr thrut ability and highr fficincy iultanouly, hn th dignd pring tiffn and ronant frquncy i incrad. V. CONCLUSION Thi papr propo a novl tubular linar ocillating otor. A hollo tructur i propod for th ovr dign bad on th lf-hilding ffct of quai-halbach PM array, hich can rduc th ovr a to iprov th otor dynaic. And thn, th ti-doain and frquncy-doain dynaic odl of LOM ar tablihd rpctivly. According to thi odl, th ronant frquncy charactritic of LOM i acquird, and by th analyi on th por output and fficincy, it i concludd that th LOM chanical ronant frquncy i th optial oring point. In addition, th influnc of LOM dynaic paratr on th ronant frquncy charactritic i invtd. A ronant capacitor i connctd to th coil to copnat th inding inductanc, and th otor por factor and chanical charactritic i rarchd. Finally, th rlationhip btn th otor por output & fficincy and ronant frquncy i conductd, and thi could provid guidanc to LOM dynaic paratr dign. REFERENCES [] J. B. Wang, D. Ho, and Z. Y. Lin, Dign optiization of hort-tro ingl-pha tubular prannt agnt otor for rfrigration application, IEEE Tran. on Indutrial Elctronic, vol. 57, pp , January. [] M. A. Rahan and P. Zhou, Analyi of bruhl prannt agnt ynchronou otor, IEEE Tran on Indutrial Elctronic, vol. 43, pp , Jan [3] S. M. Jang and S. S. Jong, Aratur raction ffct and inductanc of oving coil linar ocillatory actuator ith unbalancd agntic circuit, IEEE Tran. Magntic, vol. 37, no. 4, pp , Fb.. [4] S. M. Jang, t al., Thrut analyi and aurnt of tubular linar actuator ith cylindrical Halbach array, IEEE Tran. Magntic, vol. 4, no. 5, pp. 8-3, 5. [5] N. Chn, t al., Study on tatic and dynaic charactritic of oving agnt linar copror, Cryognic, vol. 47, no. 9, pp , 7. [6] T. W. Chun, t al., A novl tratgy of fficincy control for a linar copror yt drivn by a PWM invrtr, IEEE Tran. Indutrial Elctronic, vol. 55, no., pp. 96-3, 8. [7] L. N. Tutla, t al., Linar prannt agnt ocillatory achin: Coprhniv odling for tranint ith validation by xprint, IEEE Tran. Indutrial Elctronic, vol. 55, no., pp. 49-5, 8. [8] J. Wang, Z. Lin, and D. Ho, Analyi of a hort-tro, inglpha, quai-halbach agntid tubular prannt agnt otor for linar copror application, Elctric Por Application, vol., no. 3, pp. 93-, 8. [9] N. C. Tai and C. W. Chiang, Innovativ lctroagntic actuator applid for high-frquncy rciprocal tranlation, Elctroagntic, vol. 3, no., pp. 45-6,. [] L. Tutla, t al., A t of xprint to or fully charactriz linar PM ocillatory achin, IEEE Tran. Magntic, vol. 4, no., pp. 49-4, 5. Huihng Liang rcivd th B.S. and M.S. dgr in chanical nginring fro Northatrn Univrity, Shnyang, China, in 5 and 8, rpctivly, and th Ph.D. dgr in chatronic nginring fro Bihang Univrity, Bijing, China, in 4. Sinc Augut 4, h i an Elctrical Enginr of Satllit Por Subyt ith DFH Satllit Co. Ltd, Bijing, China. Hi rarch intrt includ linar otor, paccraft por yt, and icro-nano-atllit. 7 Int. J. Elctron. Elctr. Eng. 7