Dynamic analysis using finite elements to calculate the critical wear section of the contact wire in suburban railway overhead conductor rails

Abstract

Dynamic analysis using finite elements to calculate the critical wear section of the contact wire in suburban railway overhead conductor rails. Proc. IMechE Part F: Journal of Rail and Rapid Transit, Vol. 222, pp. 145-157, 2008. Dynamic analysis using finite elements to calculate the critical wear section of the contact wire in suburban railway overhead conductor rails F.J. Gonzalez, J.A. Chover, B. Suarez and M. Vazquez The purpose of this study is to determine the critical wear levels of the contact wire of the catenary on metropolitan lines. The study has focussed on the zones of contact wire where localised wear is produced, normally associated with the appearance of electric arcs. To this end, a finite element model has been developed to study the dynamics of pantograph-catenary interaction. The model includes a zone of localised wear and a singularity in the contact wire in order to simulate the worst case scenario from the point of view of stresses. In order to consider the different stages in the wire wear process, different depths and widths of the localised wear zone were defined. The results of the dynamic simulations performed for each stage of wear let the area of the minimum resistant section of the contact wire be determined for which stresses are greater than the allowable stress. The maximum tensile stress reached in the contact wire shows a clear sensitivity to the size of the local wear zone, defined by its width and depth. In this way, if the wear measurements taken with an overhead line recording vehicle are analysed, it will be possible to calculate the potential breakage risk of the wire. A strong dependence of the tensile forces of the contact wire has also been observed. These results will allow priorities to be set for replacing the most critical sections of wire, thereby making maintenance much more efficient. The results obtained show that the wire replacement criteria currently borne in mind have turned out to be appropriate, although in some wear scenarios these criteria could be adjusted even more, and so prolong the life cycle of the contact wire.

Validation of a new model for railway overhead line dynamics

“…This would indicate that lower loads would be beneficial, however, loss of contact between the pantograph and contact wire can cause an electrical arc, rapidly raising the temperature of the surrounding contact wire (Auditeau et al, 2013). This can cause melting and vaporisation of the contact wire, effectively increasing the wear rate (Gonzalez et al, 2008). The model described here is able to make prediction of contact force to assist in finding a mid-range in which risk is reduced of both excessive sliding wear and loss of contact.…”

“…Acceptable results can also be obtained using the modal analysis method, where the contact and catenary wires are decomposed into the sum of infinite derivable sinusoidal functions (Kia et al, 2010). Gonzalez et al (2008) used a computational modelling approach in their study on the wear rates of contact wires on the Metro de Madrid. A mass-spring-damper pantograph model featuring two lumped masses was passed under a catenary system with the wires represented by Euler-Bernoulli beams.…”

Online catenary anti‐icing technique for electric railways employing direct feeding systems

“…The term q L in (1) requires further consideration. Normally, current flows through the sliding connection between the pantograph and catenary [20]. The corresponding thermal problem mainly focuses on local temperature increases.…”

Effect of contact wire gradient on the dynamic performance of the catenary pantograph system

“…More comprehensively the contributions of both mechanical and electrical wear are described by the model of Bucca and Collina [8]. Damage caused by melting and vaporisation of the contact wire [9] and pantograph due to thermal effects, promotes additional wear [10] further limiting the service life.…”