Proceedings of the 11th WSEAS International Conference on Automatic Control, Modelling and Simulation

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1 Tempeatue measuement in contact pantogaph - AC contact line Constantin-Floin OCOLEANU *, Ioan POPA *, Gheoghe MANOLEA **, Alin-Iulian DOLAN * Electical Appaatus and Technologies *, Electomechanical ** Univesity of Caiova, Faculty of Electical Engineeing *, Faculty of Electomechanical, Industial Infomation, Envionment Engineeing ** Bd. Decebal, no. 107, , Caiova ROMANIA focoleanu@elth.ucv.o, ipopa@elth.ucv.o, ghmanolea@gmail.com, adolan@elth.ucv.o Abstact: - In this pape we pefomed a themal analyses using expeimental detemination in contact pantogaph - AC contact line. The pantogaph is asymmetic EPC type and the contact line wie is TF 100 type, both used in Romanian Electic Railways. The influence on the tempeatue value of the small contact aea between two collecto stips of pantogaph and contact wie is pointed out. Keywods: Electic ailway, contact wie line, pantogaph, contact aea. 1 Intoduction The contact between pantogaph and AC electic ailway system supply contact line is studied in liteatue and epesents an impotant poblem concening the exploitation of ails vehicles. The pantogaph - catenay system is still today the most eliable fom of collecting electic enegy fo the tain, when high speed opeational conditions ae consideed. This system should ideally opeate with elatively low contact foces and no contact loss should be obseved, so that the powe be constant. Fo themal analyses of this system we had used the mathematical model of [3], calculating the contact aea and we had made expeimental detemination. 2 Contact line-pantogaph system The pope balance between the dynamic chaacteistics of the pantogaph and the contact line depends on the quality of cuent collectos and on the longevity of the contact wie and insets. The pantogaph must suppot them with sufficient foce to emain in pemanent contact with the wie, but not unduly aise (fig.1), which would lose contact afte the points of attachment [9]. The cicula section of the contact wie has two slots fo the claws of catenay s suspensions (fig.2). Accoding to the supply voltage and powe equiements, the section anges fom 100 mm 2 to 150 mm 2. Poduced by cold dawing, the section can be cylindical o have a flat to incease the size of the sole contact with the fiction of the device outlet. The cable must ensue good mechanical taction. To decease the electical esistance of the line, the contact wie and cable ae placed in paallel, at egula intevals using a coppe shunt. The line is chaacteized by his "coppe equivalence" expessed in mm². The diffeent supply systems involve special design specifications (Table 1), depending on the intensity caied [9]. Fig.1. Factos influencing the dynamic behavio of the contact line Fig.2. Example of contact wie ISSN: ISBN:

2 Table 1. Main featues of some types of catenay Fig.5 Examples of pantogaphs In the plan, it is necessay that the laying of the contact line have a zig-zag fom the cente of the tack, so that the contact point of the bow vaies in time. A fixed point of contact would lead to the bow saw (fig.3). Fig.3 Desaxement peiodic alignment In cuve, thee should be a sepaation of mateials compatible with the width of the bow, taking into account the possible coss movements. 3 Mathematical model of contact between pantogaph and contact line As well known, when two sufaces ae in contact, the eal contact aea is much smalle than the nominal one. The contact occus in a finite numbe of aspeities that ae subjected to an elastic, plastic o combined elastic plastic defomation depending on the nomal pessue value, on the supeficial oughness and on the mateial popeties [5]. Geenwood and Williamson [5] ae the fist authos that poposed a desciptive model fo the contact between ough sufaces, which is still a benchmak fo this eseach field. The Geenwood Williamson () model is based on the fact that the contact between two ough sufaces can be consideed as an equivalent contact between a ough suface and a smooth suface (Fig.6). Each aspeity is modeled with a spheical shape with unifom adius of cuvatue whose height above a efeence plane has a nomal (Gaussian) pobability density function. The hypotheses of G-W model ae: the aspeity is spheical; the aspeities ae fa apat and thee is no inteaction among them; duing the contact, defomation only occus fo the aspeities. Fig.6 Contact between ough sufaces modeled as contact between a ough suface and a smooth suface. Fig.4 Desaxement cuve F: image of the cuve in the ange = a ² / 8R f: desaxement the ight suppot f ': desaxement in the scope The cuent collectos ae now pantogaphs "light" that povide the powe supply (fig.5). The eal contact aea is [3]: A * d ( d + c ) = A ( e + e ) (1) whee - - n n is the oughness paamete; A is nominal contact aea; - is coefficient of exponential distibution; * ISSN: ISBN:

3 Poceedings of the 11th WSEAS Intenational Confeence on Automatic Contol, Modelling and Simulation 4 Expeimental detemination - d * is standad value of the mean sepaation d; - c is standad value of the citical intefeence at the inception of plastic defomation., d*, d* = c = d Expeimentally we obtained contact tempeatue in AC fo diffeent values of the cuent. We pefomed a static detemination, consideing that the locomotive is not moving. The cuent absobed by the locomotive is necessay fo auxiliay sevices. The consideed pantogaph is asymmetic EPC type and the contact line wie is TF 100 type, both used in Romanian Electic Railways. The contact between two collecto stips of pantogaph and contact wie is made on a small suface (fig. 7, 8, 9). The measued tempeatues in contact fo 15 A, 20 A and 25 A, AC cuent ae shown in figue 10, 11, 12. ae defined as: c (2) (3) K H 2 =( ) 2 E c = K H 2 E 2 (4) whee - is suface density of aspeities; - is adius of cuvatue of aspeity; - is standad deviation of aspeities heights; - d is mean sepaation; - K is the atio between the contact pessue that gives ise to a plastic defomation and the hadness of mateial H, consideed equal to 0.6; - E is elastic modulus. Values fo,,,, K and E ae given in the table 2 [5]. Fig. 7 Contact zone Table 2 The main values of statistical paametes, both fo coppe and fo gaphite stips Fig.8 Contact zone 1 The mean sepaation d is calculated using the pobability density function (z ) : ( z) = c e d= z z ( z )dz (5) (6) 0 The calculated statistical-based value of mean sepaation d and the eal contact aeas ae pesented in table 3. Table 3 - The calculated value of mean sepaation d Fig.9 Contact zone 2 and the eal contact aea values ISSN: ISBN:

4 In figue 13 and figue 14 ae shown the themal spectums of system with infaed camea. Fig.10 Measued tempeatues in contact fo 15 A, AC cuent Fig.13 Infaed camea s view 1 Fig.11 Measued tempeatues in contact fo 20 A, AC cuent Fig.14 Infaed camea s view 2 5 Conclusion The expeimental esults show an incease of tempeatue value in both contacts fo a small cuent value at an ambient tempeatue of 20 ºC. The tempeatue in contact 2 is bigge than in contact 1 because of his smalle contact aea. In the wie between the two contact aeas the tempeatue is nealy to the value in contact 1. In futue, a numeical model of contact pantogaphcontact line fo evaluating the tempeatue values will be developed and validated by these expeimental esults. Fig.12 Measued tempeatues in contact fo 25 A, AC cuent ISSN: ISBN:

5 Refeences: [1] DNghici A., Calceanu I., Catea mecanicului de locomotive electice (In Romanian), [2] He D.H., Manoy R., Gady N., Wea of ailway contact wies against cuent collecto mateials, Wea 215, pp , [3] Bucca G, Collina A., A pocedue fo the wea pediction of collecto stip and contact wie in pantogaph catenay system, Wea 266, pp , [4] Jamai J., Schippe D.J., Expeimental Investigation of Fully Plastic Contact of a Sphee Against a Had Flat, Tansactions of the ASME, Vol. 128, pp , Apil [5] Geenwood J.A., Williamson J. B. P., Contact of nominally flat sufaces, Poceedings of the Royal Society Seies A295, pp , [6] Onea R., Constuc/ia, exploataea 0i înte/ineea instala/iilo fixe de tac/iune electic2 feovia2 (In Romanian), ASAB, BucueQti, [7] Ocoleanu C.F., Popa I., Manolea Ghe., Study of the Skin Effect Influence on Electic Railway System Supply Line Heating, Envionmental poblems and development, Poceeding of the 1 st WSEAS Intenational Confeence on Uban Rehabilitation And Sustainability - URES 2008, pp , Buchaest, Romania, Novembe 7-9, [8] Raute F.G, Pombo J., Ambosio J., Chalansonnet J., Bobillot Adien, Contact model fo the pantogaph-catenay inteaction, Jounal of System Design and Dynamics, Vol. 1, no. 3, [9] Cividjian G.A., Pascu Ileana, Bunescu A., Matei D.M., Dolan A., Expeimental study of the esistance of flat Cu-W contacts, XII-th Intenational Symposium on Electical Appaatus and Technologies - SIELA 2001, Vol. I, pp , Plovdiv, Bulgaia, May 31 - June 1 st, [10] documents/resut111.pdf ISSN: ISBN: