高速铁路信号系统雷击电磁瞬态耦合机制和防护方法研究

The high-speed railway signaling systems are particularly vulnerable to lightning strokes due to their poor insulation withstand voltages and rather exposed position along the railway track. Therefore, it has great theoretical and practical significance to study the electromagnetic transient coupling mechanism and protection method of high-speed railway signal system. Basing on combining method of theoretical analysis, simulation modeling and experimental testing, this project will reveal the electromagnetic transient coupling mechanism between signaling system and large-scale complex multi-conductor system, which composed of viaduct, rail, through ground wire and catenary. Also this project will clarify coupling mechanism of lightning over-voltage invading the signal device room simultaneously via the grounding network, signal cables, power supply lines and other ways. The characteristic of lightning over-voltage in signal system will be explored, and the comprehensive coordinated multi-level protection strategy will be proposed for the signaling system. The physical mechanism of the short-circuit failure mode induced by the cumulative effect of repetitive discharges of gas discharge tube will be studied and a suppression method will be introduced. The project is also meant to develop a new kind of modified tube without short-circuit failure, which will become a novel common-mode protection method for high-speed railway signaling system. The project research will form the theoretical system and key technologies of lightning electromagnetic transient protection for high-speed railway signaling system, and provide support for China's high-speed railway to defend against lightning hazards.

高速铁路信号系统耐受雷击电磁瞬态过电压的能力较弱，大量信号设备沿铁路线装设于户外，极易遭受雷电过电压作用导致损坏。开展高铁信号系统雷击电磁瞬态耦合机制与防护方法研究，具有重要的理论与工程应用价值。本项目通过理论分析、仿真建模、实验测试相结合的方法，揭示高架桥、钢轨、贯通地线、接触网等组成的大规模复杂多导体系统与信号系统雷击电磁瞬态耦合机制，以及信号室内信号系统雷击电磁瞬态过电压通过接地网、信号线缆、供电线路等多途径同时侵入耦合机制，研究信号系统雷电过电压的特性规律，提出信号系统多层级多途径协同配合雷电防护方法；研究气体放电管多次放电累积效应诱发短路失效的物理机理，提出防止气体放电管短路失效的抑制方法，研制无短路失效模式的气体放电管，创新高铁信号系统共模防护方法。项目研究将形成高铁信号系统雷击电磁瞬态防护理论体系与关键技术，为我国高铁防御雷电危害提供支撑。

雷电是联合国公布的十大自然灾害之一，高速铁路列车速度快，行驶密度大，雷击事故影响范围广，亟待全面提升雷电防护水平。项目围绕高铁信号系统雷击瞬态理论建模、风险评估、防护方法与装置研发存在的突出难题开展研究，主要研究内容与成果如下：（1）提出了高架桥桥墩、箱梁结构单元电磁解耦雷电电磁暂态建模方法，建立了涵盖高架桥内部巨量钢筋构成的复杂多导体系统雷击瞬态模型。提出了基于半空间部分单元等效电路法和宽频宏模型等效的混合建模方法，建立了高架桥路段“复杂钢筋网络-供电-信号”整体雷击电磁瞬态宽频模型，并在京保、福夏线开展现场雷电冲击真型实验，获得了高架桥路段大规模复杂多导体系统与信号系统雷击电磁瞬态耦合规律。（2）提出了基于全空间部分单元等效电路法、传输线建模和宽频电路等效相结合的信号室信号系统雷击多途径侵入建模方法，建立了雷击沿多途径侵入信号系统瞬态分析模型，开展了高铁信号中继站雷击通信塔冲击响应实验，获得了雷击沿天馈线、接地网和信号线缆多个途径侵入信号系统特性规律，提出了信号系统多层次多途径协调配合雷电防护方法。（3） 研究了气体放电管多次雷击放电等效实验方法，建立了放电管放电多物理参量高精度同步观测平台，揭示了管壁导电物质沉积和电极间絮状物生长是导致气体放电管多次放电短路失效的机理，研制了基于管壁环状楔形槽阻断、铁镍电极钨铜一体化、电子粉倍增优化的新型气体放电管，多次放电老化寿命提升约8~10倍，创新了高铁信号系统共模防护方法。制定了国家、行业和企业标准各1项，获得省部级科技奖励5项，项目组1人入选国家“万人计划”青年拔尖人才，1人入选中国科协青年人才托举工程。成果已应用于我国4万公里高铁信号系统雷电防护，占比99%，相关方案、技术和标准已应用印尼雅万高铁等国际工程。形成了高铁信号系统雷击电磁瞬态防护理论体系与关键技术，可为高铁防御雷电危害提供支撑。