Effect of Arc Discharge on the Wear Profile of Cu Impregnated Carbon Based Pantograph Contact Strip

Localized wear of pantograph contact strips, which may break the overhead contact wire, has been one of the significant problems in the current collection systems of electric railways in Japan. However, the causes of the localized wear have not been clarified, and effective countermeasures have not been established currently. One of the possible causes of localized wear is excessive heat generated by occurrence of arc discharge between an overhead contact wire and a contact strip, which damages surface of the contact strip. In this study, we investigated the effect of arc discharge on the wear profile of contact strips using an arc-discharge tester and a wear tester. From the results of the wear test, we found that the localized wear does not arise from the spots damaged by arc discharge. It was also found that the amount of wear of a contact strip increases with arc-discharge energy; however, the wear profile of the contact strip does not correlate with the distribution of arc-discharge energy on its surface.