【作者】 冉旺；

【导师】 郑琼林；

【作者基本信息】 北京交通大学 ， 电气工程， 2014， 博士

【摘要】 摘要：在单相工频交流供电的铁路牵引供电系统中,由于分相区的存在,在一定程度上制约了电气化铁路向更高速、更重载的方向发展。本文围绕列车过分相时实现不断电、无冲击两大目标,基于电流信息进行列车不断电过分相系统的研究,研究的问题主要包括系统方案、列车位置检测方案、列车过分相电气暂态过程、电子开关工程设计等几个方面。本论文对现有的列车自动过分相技术方案进行了对比,重点研究了地面自动过分相的现有系统方案和列车位置传感器,并分析了它们的优点与不足。在此基础上对电子开关列车不断电过分相进行系统优化,提出了列车不断电过分相系统的两种新方案,分别是中性区无位置传感器的系统方案和中性区安装一套位置传感器的系统方案。基于接触网电压和列车电流信息,进一步研究了地面电子开关的控制时序。本论文提出的方案,可有效缩短列车过分相的断电时间,列车过分相时可保持牵引力不丢失。本论文针对现有列车位置检测方法应用于电子开关系统中存在的不足,提出了基于接触网电流信息的列车位置检测方法。通过研究牵引供电方式、接触网结构分析了该方法的可行性。对接触网阻抗单元进行建模,得出了承力索电流和吊弦电流的分布规律。提出了一种基于承力索电流信息的列车位置检测方法和三种基于吊弦电流信息的列车位置检测方法。以上列车位置检测是通过监测接触网电流来实现的,因此本文设计了电流监测装置,并设计了将电流监测装置安装在支柱和腕臂上的安装方式。本文提出的列车位置检测方法可准确的定位列车受电弓的位置。本论文从理论上对列车过分相的电气暂态过程进行了研究,探讨了过电压和过电流产生的机理。通过对暂态过程的分析提出了地面开关切换过程中抑制过电流的解决方案,实现列车无冲击通过分相区。在电子开关控制过程中,接触网电压和开关负载电流的相位信息非常重要,本文对常见的几种相位检测方法进行了研究和对比,加权最小二乘法响应快,鲁棒性好,在谐波含量较大的电压波形中能准确的检测出基波相位,将该相位检测方法用于电子开关的列车带电过分相系统中检测电压、电流相位可以得到最优的结果。本论文进行了电子开关的器件选型和串联器件均压电路设计。并对晶闸管串联阀组的门极触发进行的研究,基于光隔离驱动技术研究了高压自取能技术,设计了从高压侧直接获取电能提供给晶闸管门极触发电路的取能电路,实验结果表明该取能电路可以满足高压晶闸管串联阀组的触发电路的电源需求。更多还原

【Abstract】 ABSTRACT:In the traction power supply system, there are some sections without power supply, which is called neutral section. Trains pass through these sections without power supply, and speed of trains reduces greatly. Over-voltages occur when pantograph transits from catenary to neutral section or from neutral section to catenary. It is not only harmful to the equipments, and also makes passengers uncomfortable. Neutral section is bottle-neck in the traction power supply system to preclude development of high speed railway and heavy haul railway. This dissertation researches a new system to achieve trains passing neutral section with traction load, and no shock. Meanwhile a new position detection method is proposed and studied. Simulations and experiments demonstrate the correctness of the research results.In this dissertation, influnece of trains passing neutral section has been discussed. The existed systems and train position detect methods for trains passing neutral section were compared. Based on it, two improved system schemes of grouding switch passing neutral section with electronic switches are proposed, which are one position sensor installed in neutral section and no position sensor installed in neutral section respectively. Switching logic in different system conditions has been investigated based on voltage and current of train. Deadtime when grouding switches changing-over has been discussed. The conclusion is that trains pass neutral section with traction power in the new system.This dissertation researches simple chain catenary structure. Catenary impedance has been modeled by unit, which includes a length of carrier cable, hanger and contact wire. Based on current distribution of catenary, new train position detection methods are proposed, which monitor current changing in the catenary, to detect the position of pantograph. These methods don’t need to install equipment on the train, nor interact with the train control signal, so it shows a high security performance. Then position sensor has been designed, it was based on new type current transformer and optical fibre transmission technique. The train’s position signal can be transmitted to the control system on the ground accuratly and reliable.Equivalent circuits of traction power supply system and train has been modeled, and electrical transient state process has been researched theorily. The reason of over-voltage and over-current has been discussed. Then the control strategy to avoid over-voltage and over-current is proposed. Base on the analysis and control, the new system utilizing electronic switches can eliminate over-voltage and over-current completely, so trains pass neutral section smooth and steady.This dissertation researched and contrasted several phase detection method to detect voltage phase and current phase. Through the analysis and comparison, weighted least squares method has high precision and good robustness when phase or amplitude of voltage changing suddenly, and also it has outstanding ability to obtain the phase of fundamental voltage accurately, even if voltage contains rich harmonic content. This method is the most suitable phase detection method in the electronic switches system.Finally, engineering of electronic switches were designed, including device selection, parameters design, and series thyristor drive. An improved gate driver circuit topology is proposed, in which DC power is self-created from high voltage side. It is fit for drive thyristors connected in series through experimental verification.更多还原