高速铁路接触网直接雷电过电压防护的基础理论及应用研究

With the rapid development of high-speed railway and the railway information technology, the injury degree cause by lightning overvoltage on the high-speed railway power supply system is increasingly aggravated. The lightning accidents not only cause delay, power outages and shut down, but also cause casualties. At the same time, the economic loss and social impact are difficult to be assessed. So the direct lightning protection for high-speed railway power supply system is very important.. Focused on the problem that the overvoltage protection component and protection technology widely used in power system can’t meet the direct lightning protection requirements of high-speed railway power supply system, the systematic researches of overvoltage protection gap are carried out in this project. The characteristics of an active overvoltage protective gap, which mainly include voltage protetion level, response time and power frquency following current restraining capability, are researched and the influencing laws between the protective characteristics and trigger method, trigger device, gas type and gas pressure are obtained. The physical model is estabilished and the protection mechanism of the active overvoltage protection gap is studied. . The heat conduction model of an active overvoltage protective gap is also estabilished, the relation between high lightning current transfer capability and power frequency following current restraining ability is obtained and the dielectric recovery mechanism is researched. The technical bottleneck, which is the interaction constrained problem between high current transfer ability and power frequency following current restraining capability, is broken. The optimization design theory can be put forward and an active overvoltage protection gap is developed. . The characteristics of combination overvoltage protection device composed of metal oxide arrester and an active overvoltage protection gap are studied, the coordinating law and lightning energy distribution law are derived, and the comprehensive overvoltage protection theory for high-speed railway power supply system is formed preliminarily. . These works will lay theoretical basis and technical support for further research of overvoltage protection technology and safety operation of high-speed railway power supply system.

随着高速铁路和铁路信息化技术的飞速发展，由接触网引入的雷电过电压事故日益加剧，经济损失和社会影响都难以估量，接触网的直接雷电防护是高铁雷电防护的重点。本项目针对电力系统雷电过电压防护的器件和技术无法满足高铁接触网直接雷电防护的技术难题，开展过电压保护间隙的触发方式、触发器和触发技术对过电压保护间隙的电压保护水平、响应时间影响规律的研究，阐释过电压保护间隙的导通机理；建立保护间隙的热传导模型，研究直接雷电流注入与保护间隙介质恢复特性之间的内在规律，突破过电压保护间隙大电流转移能力与工频续流抑制能力相互制约的瓶颈，提出优化主动型过电压保护间隙的设计思想；开展主动型过电压保护间隙与避雷器之间相互配合、雷电能量分配的理论和应用研究，形成高铁接触网直接雷电综合防护的初步理论，为电气化铁路系统接触网雷电过电压防护技术的深入研究以及高速铁路的安全运行提供理论基础和技术支持。

随着高速铁路和铁路信息化技术的飞速发展，由接触网引入的雷电过电压事故日益加剧，经济损失和社会影响都难以估量，因此接触网的直接雷电防护是高铁雷电防护的重点。.本项目针对电力系统雷电过电压防护的器件和技术无法满足高铁接触网直接雷电防护的技术难题，开展了过电压保护的触发方式，触发技术对过电保护间隙保护水平、响应时间的影响规律的研究，探索了保护间隙初始载流子的产生和发展过程，阐释了过电压保护间隙的导通机理；提出主动能量耦合技术并设计了主动型过电压保护间隙，建立了过电压保护间隙主动耦合触发回路的等效电路模型，得到了雷电注入下主动耦合触发回路暂态电压的解析式，提出了主动耦合触发回路元件参数的选取原则；开展了雷电冲击下主动型过电压保护间隙脉冲击穿特性的研究，发现主动型过电压保护间隙的脉冲击穿电压与直流击穿电压之比（简称为“压比”）远小于被动型保护间隙的压比；开展了主动型过电压保护间隙后续工频电流遮断能力的研究，获得了过电压保护间隙的后续工频电流遮断能力与过电压保护间隙距离、气压、雷电流参数以及工频参数之间的关系，并获得了主动型过电压保护间隙与后级限压型过电压保护器件雷电能量分配关系，在此基础上，优化过电压防护间隙的结构参数和环境参数，并形成了过电压防护间隙成套的性能检测技术和测试平台，并拓展了多重连续雷电分量实验设备在电力输配电防雷地线雷电效应的研究，为过电压防护技术和防护器件的研究和应用奠定了理论和实验基础。