高速列车车顶绝缘子动态积污特性及污秽高光谱检测方法研究

The roof insulator is the key equipment of high-speed trains for high-voltage isolation and mechanical support. High-speed trains usually across multiple provinces and areas with different pollution levels. The operating conditions are harsh, the environments are changeable, and the sources of pollution are complex. Therefore, the pollution on the roof insulator is serious and the pollution distribution is uneven, pollution flashover has become one of the key issues that threaten the safe operation of high-speed railway. The existing detection methods of pollution condition for roof insulators have some limitations, while the hyperspectral spectrum technology can image the targets in different wavelengths including ultraviolet, visible light, near-infrared and infrared regions with high spectral resolution, which also contains both the image and the spectrum information. So it shows great potential in the detection of pollution condition on roof insulators. In this project, the pollution deposition mechanism of roof insulators will be revealed by analyzing the physicochemical property and establishing the dynamic pollution accumulation model. The hyperspectral characteristics and its response mechanism will be studied, and the spectral library of typical pollution components will be established. Based on the spectral disaggregation and inversion techniques, the hyperspectral model of pollution condition will be constructed to identify the types, contents and distributions of pollution on roof insulators. On this base, a new pollution condition detection method for the roof insulators used for high-speed trains will be proposed.

车顶绝缘子是高速列车高压隔离与机械支撑的关键设备。髙速列车运行区间通常横跨多个省份以及不同等级污区，运行工况恶劣、环境多变，污秽来源复杂，车顶绝缘子积污严重且污秽非均匀分布特征突出，污闪已成为威胁高速铁路安全运行的关键问题之一。现有车顶绝缘子污秽状态检测方法均有一定的局限性，而高光谱成像技术可在电磁波谱的紫外、可见光、近红外和中红外区域波段对目标区域进行成像，具有很高的光谱分辨率，并包含图像与光谱双重信息，在车顶绝缘子污秽状态检测方面具有很大的应用潜力。本课题通过分析车顶绝缘子典型污秽理化特性并建立动态积污模型，揭示绝缘子表面污秽沉积机制；研究车顶绝缘子表面典型污秽高光谱特性及响应机理，建立典型污秽成分特征波谱库；基于光谱反演技术构建车顶绝缘子污秽状态高光谱表征模型，实现绝缘子污秽类型、含量及分布的高光谱识别，在此基础上提出基于高光谱技术的高速列车车顶绝缘子污秽状态检测新方法。

车顶绝缘子是高速列车高压隔离与机械支撑的关键设备。髙速列车运行区间通常横跨多个省份以及不同等级污区，运行工况恶劣、环境多变，污秽来源复杂，车顶绝缘子积污严重且污秽非均匀分布特征突出，污闪已成为威胁高速铁路安全运行的关键问题之一。本项目基于实验室风洞系统，研究了不同风速、不同污秽类型、不同污秽颗粒粒径、不同绝缘子结构等参数影响下，污秽颗粒在绝缘子表面的分布特性，结合实验与仿真结果，构建了典型污秽在车顶绝缘子分布特征模型，探明了高速列车车顶绝缘子污秽分布规律；建立了基于污秽类型、盐灰密及分布的污秽状态综合评估模型，提出了车顶绝缘子污秽状态光谱表征方法，实现了绝缘子污秽状态的准确评估；针对车顶绝缘子绕流运动与气流中的固体颗粒物受力情况，提出了车顶绝缘子伞裙形状结构优化策略；基于电-流体动力学和电-弹性动力学理论，提出了一种超疏水纳米结构表面，能让低湿度下车顶绝缘子的表面污秽在麦克斯韦应力、表面张力和电场力作用下发生电聚集和电运动，借助电场作用直接调控超疏水表面污秽，实现污秽在超疏水纳米结构表面的自聚集和脱离。