高速列车机械牵引传动系统的失效机理及时变可靠性关键技术研究

As the most important component of high-speed trains, the performance of traction drive system is a critical factor for train operation. Due to the high speed, heavy load, and complex internal and external excitations, failures of traction drive system have seriously threatened the safety of train operation. Therefore, it is necessary to systematically analyze and quantify the internal and external stimulates, set up the dynamic model of the mechanical traction drive system under multi-physical field coupling excitations, and explore the dynamic evolution process of its failure mechanism and key reliability technologies. Based on the CRH3 high-speed train, main researches are focused on dynamic modeling of the traction drive system, and its failure mechanism analysis and reliability assessment technologies. First, monitoring and investigation of mechanical failure of the traction drive system will be carried out through extensive on-track tests. Considering the dispersion and randomness of uncertain factors, following studies will be conducted successively: dynamic modeling of mechanical traction drive system, relative experiments on the test bench, its failure modeling and analysis, and time-dependent reliability assessment analysis and assessment. At last, researches on life prediction technology of the mechanical traction drive system will be carried out. This project covers the whole life cycle of train design, manufacture, operation, and maintenance, contributing to improvement of design level of high-speed train traction drive system of our country and reliability design theory.

牵引传动系统作为高速列车最重要的组成部分，其性能是影响列车运行的关键因素。高速列车的高速和重载，加上复杂的内外部激励，导致的牵引传动系统失效问题已经严重威胁列车运行安全。因此系统分析与量化内外部激励，构建耦合激励下的机械牵引传动系统的动态仿真模型，探究其失效的动态演化历程及可靠性关键技术势在必行。本课题以CRH3动车组为对象，按照高速列车机械牵引传动系统动力学建模、失效机理分析与可靠性评估、寿命预测研究主线，在对牵引传动系统机械故障调研的基础上，结合车辆运行不确定因素和服役性能随时间变化的规律的分析，深入开展机械牵引传动系统动力学建模、故障物理建模与分析、疲劳时变可靠性分析与评估方法研究。在此基础上开展机械牵引传动系统寿命预测方法研究，支撑高速列车牵引传动系统设计、制造、使用及维护，并完善其可靠性设计理论。

牵引传动系统的性能很大程度上决定了高速列车的动力品质、能耗和控制特性，也是影响高速列车的经济性、舒适性和可靠性的关键因素，保证牵引传动系统的可靠性是提高高速列车运行效率和安全性的必要途径。但传统的高速列车机械牵引传动系统疲劳失效分析和可靠性研究缺乏考虑实际服役环境和载荷特征，难以明确机械牵引传动系统的失效机理，对其缺陷提出针对性的改进措施。同时，针对高速列车机械牵引传动系统的时变可靠性高精度模型构建方法以及高精度、高效率的系统可靠性评估和寿命预测方法的研究较为匮乏。因此，本项目以高速列车机械牵引传动系统为研究对象，进行失效机理分析及失效判定准则的制定，研究负载载荷作用下时变可靠性指标的建立、时变可靠性评估与设计，并开展基于故障物理的牵引传动系统寿命预测。以失效机理分析入手，开展故障分析以及危害度和重要度评估，研究随机载荷、不确定性等因素作用下的静/动态可靠性和时变可靠性，并进行疲劳寿命预测和优化设计。研究内容主要包括如下几个方面：（1）复杂载荷作用下机械牵引传动系统的动态响应规律；（2）关键部件的危害度评估和故障模式预测；（3）考虑不确定性因素影响下的结构静态/疲劳强度；（4）高精度、高效率代理模型和算法研究以及可靠性模型和寿命预测模型的构建；（5）考虑相关性的时变可靠性分析和寿命评估方法研究；（6）基于可靠性的关键零部件多目标、多学科优化设计，以及文件优化研究。通过上述研究，本项目所提出的方法和理论对牵引传动系统可靠性的提高和服役寿命的延长，具有重要应用价值。