Assessment of the Current Collection Quality of Pantograph–Catenary With Contact Line Height Variability in Electric Railways

The numerical tools are widely used to facilitate the design of the railway catenary. Only radical results are obtained as the current assessment is generally performed without any practical errors. In this article, the most common error, the contact line height variability, is appropriately included in evaluating the current collection quality. Based on the real-life contact line height data collected from a high-speed network, the heights of the key points in the contact line are extracted, of which the pointwise stochastics is represented by the power spectrum density (PSD) function. Random samples are generated by the inverse Fourier transform based on the Monte Carlo method. An advanced initialization procedure is presented to properly include the contact line height variability in the initial configuration. A stochastic analysis with a high cutoff frequency is performed to evaluate a double pantograph–catenary system’s current collection quality. Unlike the deterministic result obtained by the perfect design data, the contact line height variability causes uncertainty. The present analysis method indicates some risks of safety accident and contact loss that the traditional simulation cannot capture with ideal design data or low cutoff frequency.

I. Introduction

In electric railways, the catenary constructed along the railroad is used to provide continuous electric current for the locomotive via pantographs mounted on the carbody’s roof, as shown in Fig. 1. As a crucial part of the traction power system [1], the sliding contact performance between the pantograph and the catenary directly determines the current collection quality. A deteriorated contact quality of the pantograph–catenary mainly reflects in an incremental fluctuation in the contact force. An overlarge contact force causes extra stress and wear in the pantograph strip [2] and the contact line [3] and reduces the system’s life expectancy. An inadequate contact force increases the probability of arcing occurrence, which may burn the contact surface and cause electric transmission issues [4], [5]. Therefore, good contact quality is desired to enable a fast and safe train without traffic disorders. Fig. 1.

Schematic of a pantograph–catenary system.