THE STUDY OF THE SYSTEMS USED FOR THE POWER SOURCES COUPLING

Transcription

1 UNIVERSITY OF PITESTI FACULTY OF MECHANICS AND TECHNOLOGY SCIENTIFIC BULLETIN AUTOMOTIVE seies, ye XIX, no THE STUDY OF THE SYSTEMS USED FOR THE POWER SOURCES COUPLING Dinel POPA *, Nicole Dou STĂNESCU, Iin TUDOR Univesity of Pitesti, Romni Aticle histoy: Received: 57; Accepted: 9 Abstct: In this ppe we pefom eview of the pinciples nd technicl solutions used fo the powe souces coupling Fo mechnicl system tht uses plnety two degees of mobility system the uthos elize the kinemtic nd dynmic nlysis to obtin the equtions of motion Finlly, fo n utomobile equipped with such plnety mechnism, we detemine the equtions of motion, eqution tht my be numeiclly integted Keywods: powe souces, hybid utomobile, plnety mechnism, Lgnge s equtions INTRODUCTION The coupling of the powe souces is minly elized fo the populsion of the hybid utomobile, whee the populsion enegy is povided by two souces bsed on diffeent pinciples fo the enegy s genetion In the compounding of such system thee min components e included: souce of ievesible enegy, souce of evesible enegy, nd coupling system tht pemits the tnsmission of the motion to the utomotive wheels (Fig ) Ievesible powe souce Sistem de cuple Revesible powe souce Figue Hybid populsion system The souce of ievesible enegy is, usully, system consisting in esevoi of fuel nd theml engine o geneto with fuel cell Hence, the chemicl enegy is tnsfomed in mechnicl enegy The souce of evesible hs lso two components: system fo enegy stocking nd souce of echging The stocking system my be: n electo-chemicl ccumulto, supe- cpcito, n inetil flywheel o n oleo-pneumtic system The echging souce pemits the intoduction of the enegy in the system The coupling system ssues the coupling of the two enegetic souces nd the tnsmission of the motion to the utomotive wheel This system my hve mechnicl o electic components * Coesponding utho Emil: dinelpop@upito

2 MECHANICAL COUPLING SYSTEMS Plnety mechnisms e used in lmost evey mechnicl systems to couple the powes given by theml engine nd two electic mchines This is the solution used by Toyot Compny fo its model Pius The system is symbolized THS (Toyot Hybid System) o, newe, HSD (Hybid Synegy Dive) In Fig is pesented the kinemtic scheme of the mechnicl coupling system The plnety mechnism denoted by PSD (Powe Split Device) elizes division of the powe stem The dvntge of such solution is simplicity, elibility nd obustness The theml engine MT is linked to the pot-stellite m, the electic mchine to the sol wheel, nd the electic mchine to the cown ge PSD IE CC/CA BAT MT z P z z L z 5 P z 6 Figue Mechnicl coupling system Toyot Pius solution The electic mchines nd e used eithe s motos, o genetos, depending on the velocity of the utomobile They e coupled to the electic bttey BAT of high voltge (7 V) by n electonic invete IE The motion is tnsmitted using chin geing L, fom the pinion P fixed to ottion to the xle of the electic moto, to the pinion P, nd, futhe on by the ge z5 z6 to the moto wheels, using the diffeentil ge D In Fig, by dshed lines, wee dwn the electic connections, nd by continuous line, the mechnicl ones D z MT z 6 z 7 z 6 IE CC/CA BAT 7 z z' z 5 z" D Figue Mechnicl coupling system Lexus LS-6H solution A simil plnety mechnism is used by Lexus LS-6H utomobile As opposed to the mechnism 6

3 of Toyot solution, this plnety mechnism is double one, the second plnety mechnism (Fig ) consisting in the cown ge ( z teeth), plnety pinions 6 ( z 6 teeth), nd the sol wheel 7 ( z 7 teeth) fixed to ottion to the electic mchine This mechnism hving the stellites xes 6 fixed becomes speed-educe nd, theefoe, it mplifies the tnsmitted moto toque by the electic mchine The motion is tnsmitted by the ge z z5 to the min tnsmission of the utomobile HYDRAULIC HYBRID SYSTEMS The hydulic hybid systems tke the mechnicl enegy fom the theml engine using hydulic mchine which woks s hydulic moto in the inush phse nd s bke in bking phse Such systems e minly used fo the medium nd hevy utomotive populsion The best solution of such system is tht of the Austlin Compny Pemo Dive Technologies, which, with the RDS model (Regenetive Dive Systems) equipped the mility utomotive FMTV (Fmily Medium Tcticl Vehicles) with six moto wheels nd tnsmission with ges pemitting eduction of fuel of bout 7% - 7% In the sme time, wee eched the cceletion pefomnce by 6% nd bking ones by 6% The hydulic hybid systems my be seies (Fig, ) o pllel (Fig, b) systems The seies hydulic systems (Fig, ) consist in hydulic mchine HPM, low pessue ccumulto LPA, high pessue ccumulto HDA nd hydulic cting system HDA This ssembling contins hydulic moto tht convets the stocked hydulic enegy into mechnicl enegy The necessy enegy fo the system is povided by the theml engine MT The pllel hydulic systems (Fig, b) ecove the kinetic enegy in bking nd convet it in hydulic enegy; they stock this enegy to be used t the inush o cceletion phse The system consists in hydulic mchine HPM, esevoi of low pessue fluid FR, nd n hydulic ccumulto of high pessue HPA with nitogen pillow (to stock the ecoveed hydulic enegy) the powe stem closes, in both diection, though the font mechnicl tnsmission SM, theml engine MT, e mechnicl tnsmission SM S, nd the font nd e moto wheels F LPA M SM F MT HPM HPA FR HPM HPA HDA SM S ELECTRIC COUPLING SYSTEMS ) b) Figue Hydulic hybid systems In this cse the cting of the moto wheels is pefomed by the electic motos, the theml engine hving the ole to povide enegy in the system Thee e sevel solutions In the cse of the seies hybid in Fig 5,, the theml engine MT cts the electic geneto GE, the enegy thus obtined is stocked in the tction bttey BAT The stocking of the enegy nd then its use is contolled by the electonic invete IE The evesible electic mchine ssues the populsion (in moto egime) nd the ecovey of the enegy t 6

4 bking (in geneto egime) The mechnicl enegy of the theml engine MT completely psses to the electic geneto GE tht convets it in electic nd then electo-chemicl enegy in the bttey BAT This tnsfomtion educes the efficiency to 7% - 8% In the cse of the seies hybid without the stocking of enegy t the bking in Fig 5, b, the system is simple One uses one electic moto ME nd one plnety ge RP fo ech moto wheel The theml engine cts the electic geneto GE, nd commnd modulus IC ssues the electic enegy to the motos t wheels Such solutions e used t the electic Diesel engines (since moe thn 6 yes) nd some mility 8x8 utomotive RP RP GE BAT IE CC/CA MT GE MT IE CC/CA RP RP D ) b) Figue 5 Seies electic hybid systems THE EQUATIONS OF MOTION OF THE MECHANICAL SYSTEMS USED IN THE POWER SOURCES COUPLING As we mentioned in pgph, the mechnicl systems use plnety mechnism with two degees of mobility to couple thee powe souces: theml souce two electic souces We will nlyze the solution cptued in Fig We denote by z, z nd z the numbe of teeth of the ges,, nd, espectively To be out to obtin the kinemtic eltions, we will pply the Willis eltion fo the study of the eltive motion with espect to the pot-stellite If we will denote by, nd the bsolute ngul velocities of the stellite pinion, plnety pinion, nd ge cown, espectively, nd by the bsolute ngul velocity of the pot-stellite, we obtin fo the mechnism in Fig the eltions z z,, () z z which led to z () z If we denote by i the tio z i, () z then we obtin fom eltion () ( i i () ) The pevious expession gives the link between the ngul velocities, nd 6

5 If we denote by i the tio z i, (5) z then fom the second expession () we obtin the link eltion between, nd ( i ) i (6) To obtin the Lgnge equtions we detemine the expession of the mechnicl powe P P M M M, (7) whee by M, M nd M wee denoted the vlues of the moto toques fo: the theml engine, the electic mchine, nd the electic mchine, espectively Keeping into ccount the eltion (), the expession (7) becomes P M M ( i) M im (8) The vition of the elementy wok is L M M ( i) M im (9) Consideing tht the genelized foces Q nd Q esult fom the expession of powe P Q Q M j j Fjv j () whee M j, j F j mk the foces nd toques tht ct onto the system, we get the genelized foces Q nd Q Q M M ( i), Q M im () Fo the plnety mechnism the expession of the kinetic enegy T is T J J mr J J, () whee by J, J, J, J we denoted the inetil moments of the elements of mechnism, by R the dius whee thee e the pot-stellite pinions, while m is the mss of these pot-stellite pinions With the nottions: A J J i mr J i, B J i i Ji i, C Ji Ji J, () the eltion () becomes T A B C, () whee nd sty fo the ngul velocities nd To obtin the Lgnge equtions d T T dt k k Qk, k,, (5) one detemine the ptil deivtives T T T A B,, T B C,, (6) whee nd e the genelized coodintes By eplcing the pevious expessions in the eltion (5), one obtins the system of equtions A B M M i, B C M im, (7) wheefom esults the system of two second ode diffeentil equtions CM M i BM im AC B, AM im BM M i AC B (8) 6

6 THE FUNCTIONING WAYS OF THE HYBRID SYSTEM In inush egime fom est, the utomotive is cted by the electic mchine (Fig ) tht woks s electic moto The expession of powe given by eltion (7) is P M The moto is chged by the invete IE fom din hulge bttey, nd the theml engine is stopped ( ) The ngul velocity of the electic mchine, ccoding to the eltion () is i ; hence the electic mchine ottes in opposite diection to the electic mchine When cetin speed (5 6 km/h) is exceeded, one goes on the theml engine using the electic mchine s electic moto The invete IE chges fom the hulge bttey BAT the motos nd Consideing constnt ngul velocity fo the electic mchine of 5 d s, it esults the expession of the ngul velocity of getting wy fo the theml engine 5 i MT, If we will conside fo i the vlue i, nd the getting wy ngul i velocity of the theml engine s 5 d s, then it will esult the ngul velocity of the electic mchine, 5 d s Fo the displcement t constnt vege speed, the utomotive is popelled by the theml engine nd the electic mchine poduces electic enegy fo the chging of nd, şi eventully, the chging of the hulge bttey The expession of powe given by the eltion (7) will be P M M M Fo the displcement t constnt high speed, is blocked, the utomobile being popelled by MT nd chging by the hulge bttey by the invete IE Between the two powe souces thee exists the tio ( i ) i, while the expession of powe is P M M At mximum velocity e coupled MT, nd, which woks s moto nd is otted in opposite diection by the electonic system IE Fo the sme ngul velocity of the theml engine, will hve gete ngul velocity if is t moto egime nd otted in opposite diection Both electic mchines e chged by the hulge bttey BAT, the expession of powe being P M M M Fo the ecoveing bke, will function s electic geneto, the poduced enegy chges the bttey BAT MT is stopped, nd is unplugged nd ottes in open cicuit with the ngul velocity i, hence in opposite diection to the mchine Fo the evese displcement, the moto ottes in opposite diection to its usul diection, MT is stopped, nd ottes fee THE EQUATIONS OF MOTION OF THE HYBRID AUTOMOTIVE The equtions detemined in pgph 5 descibe the functioning of the plnety mechnism To detemine the equtions of motion of n utomotive popelled by such system of powe coupling, we begin gin fom the expession of mechnicl powe P M M M P P, (9) whee by P ws denoted the powe consumed becuse of the olling esistnce, nd by P the powe consumed becuse of the i esistnce Thei expessions e P F v, P F v, () whee F f G, F cx A v () We used the clssicl nottions: F olling esistnce, F i esistnce, f coefficient of the olling esistnce, G utomobile s weight, i density, c x coefficient of i esistnce, A 65

7 mximum i of the coss section of utomotive, v displcement velocity of the utomotive Denoting by i the tio of the pincipl tnsmission of utomotive nd keeping into ccount the kinemtic scheme in Fig, it esults the expession of the ngul velocity of wheel () i i i We denoted by i the tnsmission tio of the chin tnsmission, nd by i the tnsmission tion of the ge fomtted by the ges z 5 nd z 6 P z6 i, i () z P Denoting by the olling dius of the utomotive wheel nd keeping into ccount the pevious eltions, we obtin the expessions of the powes P nd P P G f, P cx A () Replcing the eltions () in expession (9), we get P M M M G f cx A (5) i i We used the sign in font of the toque M becuse the electic mchine in Fig my be geneto nd then it consumes powe, o it my be moto nd then it bings powe in system Keeping into ccount the eltion (), the expession (5) becomes G P M M ( i) M im cx A (6) The vition of the elementy wok eds G ( ) cx A L M M i M im (7) i Hence, the genelized foces Q nd Q hve the expessions ( G cx A Q M M i), Q M im (8) The expession of the kinetic enegy T given by the eltion () is completed by the kinetic enegy of the utomotive, which, in simplified model, my be consideed consisting in: two font moto wheels with the inetil moments J RF, two e fee wheels with the inetil moments J Rs, nd the utomotive of mss m hving tnsltionl motion In the expessions of the inetil moments of wheels, we lso consideed the inetil moments of the bking systems, moto xes etc T J J mr J J m J RF J RS (9) Poceeding nlogiclly to the plnety mechnism, with the nottions A J J i m R J i B J i i J i i, 5, m ( J RF J ) () RS C Ji Ji J, one obtins the expession of the kinetic enegy T A B C, () whee nd sty fo the ngul velocities nd The Lgnge equtions given by the expessions (5) ed now 66

8 A B M M i, G cx A B C M im, () wheefom it esults the system of two second ode diffeentil equtions G c A x CM M i B M im i, AC B () G c A x A M im BM M i i AC B Integtion of the moving equtions () is elized numeiclly, fte we fistly estblished the necessy vlues to detemine the constnts CONCLUSIONS The hybid utomotive is not new, the mjoity of constuctos hving such models in the fbiction pocess The divesity of the consideed solutions mde necessy clssifiction nd the estblishing of cetin mechnicl pmetes to descibe the used systems This ppe mkes genel oveview of the coupling systems used in the popelling systems configutions We pesented the pinciples nd genel chcteistics of the hybid popelling systems Due to the high efficiency, the mechnicl systems of powe coupling e lmost exclusively used to couple the powe souces t utomotive of smll o medium cylindicl cpcity Fo the mechnicl coupling system used t Toyot Pius configution, we elized kinemtic nlysis nd dynmicl one, obtining the moving equtions of the mechnism cted by theml engine nd two electic mchines This mechnism is then studied in the compounding of hybid utomobile, estblishing the moving equtions fo the utomotive In futue ppe we will discuss diffeent numeicl situtions REFERENCES [] Pnde, N, Pop D, Mecnisme Teoie şi plicţii CAD, Ed Tehnică, Bucueşti, [] Pop, D, Chioiu, V, L Muntenu, J Onisou, A Iovici: On the modeling of hybid systems, Poc of the Romnin Acdemy, Seies A: Mthemtics, Physics, Technicl Sciences, Infomtion Science, vol 8, n, 7 [] Open, I M, Automobilul moden Ceinţe, esticţii, soluţii Ed Acd Române, Buc, [] Cistescu C, Recupee enegiei cinetice l fâne utovehiculelo, Ed AGIR, Buc, 8 [5] Minescu D Sisteme neconvenţionle de populsie şi tnspot, Ed Univesităţii din Piteşti [6] Pennestì, E, Miti, L, Vlentini, P, P, Mucino, V, H, Efficiency evlution of geboxes fo pllel hybid vehicles: Theoy nd pplictions, Novembe [7] Wng, C-L, Yin, C-L, Zhng, T, Zhu, L,, Powetin design nd expeimentl esech of pllel hybid electic vehicle, Intentionl Jounl of Automotive Technology, Vol, No 5, pp (9) [8] Mnsou, C, Clodic, D, Dynmic modeling of the electo-mechnicl configution of Toyot Hybid System seies/pllel powe tin, Intentionl Jounl of Automotive Technology, Vol, No, pp 66 () 67