【作者】 王波；

【导师】 范建斌；

【作者基本信息】 西南交通大学 ， 高电压与绝缘技术， 2012， 硕士

【摘要】 弓网系统(受电弓-接触网)是高速铁路动车组能力供给的核心,随着高速铁路运营速度的提升,弓网离线率显著增加,导致弓网电弧频发,严重影响了动车组的能受流质量,成为制约我国高速铁路速度进一步提升的瓶颈。在受电弓滑板与接触网导线(以下简称“弓-网”)分离或者接触的瞬间,受强电场作用“弓-网”之间的气隙被击穿时引发弓网电弧；且能量的激变会使机车电气参数发生变化从而产生离线过电压。弓网电弧电压和电弧电流中存在丰富的直流分量和高次谐波,直流分量入侵车载变压器,会使其励磁电流畸变、铁心饱和,影响车载变压器的正常工作；离线过电压则严重影响车载电气设备的绝缘性能和使用寿命,这些问题对机车的行车安全构成巨大威胁。因此,研究弓网电弧的谐波特性及其对车载变压器的影响具有重要的理论意义和工程应用价值。本文结合电气化铁道的运行特点和气体放电理论,阐述了弓网电弧的产生机理,利用弓网电弧模拟试验系统,进行了弓网电弧的动态特性试验,分析了弓网电弧谐波特性与列车牵引电流和运行速度的关系、负载特性对弓网电弧能量的影响和离线过电压的影响规律。建立了弓网电弧和主要车载电气设备的模型,构建了简化的牵引供电系统模型,按离线时间将弓网离线划分为小离线、中离线和大离线,仿真分析了不同离线方式下的过电压水平；构建了变压器直流偏磁和励磁涌流的仿真模型,分析了不同直流分量时励磁电流和励磁涌流的影响规律。最后,针对离线过电压、直流偏磁和励磁涌流等问题分别提出了相应的抑制措施,并对其抑制效果进行了验证分析。更多还原

【Abstract】 The engineering practice indicates that the interaction between pantograph and overhead contact line has become the shackles that confine the development of the high-speed electrical railway, while the pantograph arcing is one of the key problems in overhead contact system (OCS). The pantograph arcing is the arc that generated by the breakdown of the air gap between the pantograph and the cantanary under strong electric field at the moment when the pantograph strip contact with or separate from the overhead line. It will cause overvoltage when the pantograph strip contact with or separate from overhead line and the overvoltage will be a great threat to the on-board electrical equipment’s insulation. The arc voltage and current waveform contain abundant DC component and higher harmonics. Once the DC component flow into the traction transformer, it will lead to exciting current waveform distortion and core saturation, which pose a threat to the locomotive’s safe operation. Thus, it has a great theoretic importance and application value to research the harmonic properties of the pantograph arcing and its effects on the traction transformer.In this paper, the generating mechanism of the patograph arcing was presented, based on the operating properties of the electrical railway and the gas discharge theory. The Pantograph-Catenary Arcing Experiment System (PCAES) was developed to carry out the dynamic characteristic test of the pantograph arcing. The relationship between the Pantograph-Catenary harmonic property and the locomotive’s traction current and the travelling speed as well as the influence of the load characteristics on the Pantograph-Catenary Arcing energy and the influencing factors of the contact-loss over-voltage were reasearched and analyzed.The model of the pantograph arcing and the main vehicle electrical equipment was established, and also the simplified traction power supply system model has been built to calculate the over-voltage level under different contact-loss modes which can be divided into three types according to the contact-loss duration. The transformer’s DC bias and excitation inrush current simulation model was made to analyze the influencing factors of the inrush current and the excitation inrush current under different DC component.The restrain measures aiming at the contact-loss over-voltage, DC bias and the excitation inrush were proposed, and the restraining effect was studied and verified as well.更多还原