Distribution Correction Model of Urban Rail Return System Considering Rail Skin Effect

The problem of high rail potential is common in urban rail transit lines that use running rail to return train current. At present, the research of rail potential mainly adopts modeling analysis. However, the rail potential results of the traditional model are generally far less than the actual situation, and the distribution is not accurate enough. It is difficult to predict the rail overvoltage in actual operation by the traditional model. This article explains the reason for the low accuracy of the traditional model from the perspective of the rail skin effect and corrects the rail resistance parameters of the traditional model. A calculation method of rail skin effect equivalent resistance is proposed, and a distribution correction model is established to simulate the rail potential. Compared with the traditional model, the rail potential results of the correction model are obviously increased, and the value and distribution of rail potential are closer to the actual system. The accuracy of the traditional model is improved obviously after the correction of rail resistance parameters, and the problem of inaccurate analysis and prediction of OVPD by traditional models has been solved.