通信工程文献翻译——摘要：在高速列车运输系统中一个重要的问题是对于悬挂线与受电弓之间的接触压力的控制。事实上，悬挂线的刚度不是一个恒量（由于悬浮系统），这会导致接触压力振荡，其频率及其大小主要取决于列车的速度。这样的振荡可能会引起电流反正弦从而毁坏机械结构和减弱系统的性能。在此我们考虑悬挂线的刚度是一个不确定因素而需要补偿。假设对实际接触压力的测量足够精确是可能的，那么基于更高级变化的输出反馈控制计划的用途将在本文中所提议。实际的系统结构，以及十分著名的变化模式的控制的性能，考虑到可能完全拒绝接触压力中不受欢迎的振荡意味着连续压力作用于活动受电弓的下部结构，模拟仿真结构就可以提供。

关键词：受电弓，高速列车，不可靠系统，非线性系统，可变结构控制

1 介绍

长久以来对于列车受电弓和顶部装置之间的交互问题一直都被忽视了，特别是欧洲和日本的研究人员。事实上，这样的问题影响着电流采集的质量，并且是铁路系统中试图提高列车速度要克服的主要困难引自[10，12，18]。

在所有的控制条件中最基本的要求是有一个几近是常量的接触压力值（一般是100牛）。抵消接触压力大小的变化可以通过两种途径获得。一是提高接触线的承受压力（这样提高了它的刚度）。二是提高接触压力系数[18]。事实上，第一种途径非常的昂贵，它需要互连的铁路系统有同样的标准，而后者则意味着设备的快速老化。现如今，很多的铁路公司都使用了不同的解决方法。

一个有效的解决这个问题的途径是使用活动的受电弓，下面或者上面的臂状结构支持电流采集器的开启（意思就是水压或者电流发动机）引自[10，18，7，17，22，9]。在[10]中提到下部结构有用的转移单一无线补偿，而在[18]中反馈控制器的静态情形将被提及。

为了提高控制器的性能，对于受电弓和高架系统的许多控制方案混合上一种单一动力的模型都已经被提到。在[17]中提到一种受电弓的线性模型，和一种悬挂的平均等刚度，都已经被考虑到用来设计一个LQR来削弱接触压力的起伏波动；尽管如此，结果控制器在列车高速时还是没有影响。

事实上，刚度的改变，将从距离上修正从塔上通信的高值到跨度中心的值，并且速率的这些变化依靠列车的速度[22]。基于以上的考虑，特别的考虑了刚度的一种近似的模型，使用一种依靠实际列车速度[7]的合适的参数适应方法，或者使用一种特别的控制技术[11]在近些年得到了发展。

可变构造控制（VSC）变化模型作为一种有效和唯一的解决不确定系统[21，20]的途径而被认可。而VSC主要的缺点是由高控制权力组成，必须要把不确定度抵消，而且要通过开关控制作用能引起带动现象[21]。许多控制方法，基于滑动近似的中断控制规律[20]或者使用渐近情形的观查[21]，都已经建议用来削弱带动现象。

一个不同的方法是限制连续信号在真实设备控制中的更高的派生，所以在渐进的或者是限定的时间[13，2]高级顺序变化模型（HOSM）出现了。而且，HOSM允许......

Abstract: One of the main problem in high-speed train transportation systems is the control of the contact force between the catenary and the pantograph collector end. Indeed, the equivalent stiffness of the catenary is not constant (because of the suspending system) and this leads to contact force oscillations whose frequency and magnitude mainly depend on the train velocity. Such oscillations can originate electric arcs that damage the mechanical structure and reduce the system performance. Here we consider the equivalent stiffness of the catenary as an uncertainty to compensate for. Assuming that a sufficiently accurate measure of the actual contact force is available, the use of an output-feedback control scheme based on higher-order sliding modes is proposed in this paper. The actual system structure, and the well known robustness properties of sliding-mode control, allow for the almost-complete rejection of the undesired oscillations of the contact force by means of a continuous force acting on the lower frame of an active pantograph. Simulation results are provided.

Keywords: Pantographs, High-speed train, Uncertain systems, nonlinear systems, VSC.

1 Introduction

The problems related to the interaction between the train pantograph and the overhead equipment have been investigated since a long time, especially by European and Japanese uncertain. Indeed, such problems deteriorates the quality of the current collection, and are the main difficulties to overcome where trying to speed-up the train velocity of a railway system [10,12,18].

A common request is that of having an almost constant contact force (generally of about 100 N) in all operating conditions. The counteraction of the variations of the contact force magnitude could be obtained either by increasing the tension of the contact wire (so increasing its equivalent stiffness) or by increasing the contact force modulus [18]. Actually, the first solution is quite expensive, and it would need that connected railway systems have the same standards, while the latter implies the fast wearing of the equipment. Nowadays, several railway companies use different solutions.

An interesting approach to the problem is that of using active pantographs, in which either the lower or the upper frame of the arm supporting the current collector is actuated (by means of hydranlic or electrical......