基于高速列车多工况运行数据的牵引传动系统支撑电容的寿命评估

Life Evaluation of DC-Link Capacitor of Traction Drive System Based on Multi-conditions Data of High-speed Train

高速列车牵引传动系统中,支撑电容是不可或缺的储能与滤波元件。然而,在高速列车运行的过程中,支撑电容由于受到高纹波电流、高纹波电压、多变的环境温度的影响,其可靠性的研究存在巨大的挑战。根据牵引传动系统支撑电容采用的薄膜电容的特点,文中首先从薄膜电容的物理、电路结构与失效机理出发,分析了影响薄膜电容可靠性的内在因素。其次,基于薄膜电容的功率损耗计算方法,对其进行了电热应力分析,结合薄膜电容的寿命评估模型以及实车运行采集的广州南到长沙南的某车型动车组的多工况运行数据,对牵引传动系统的支撑电容的寿命在试验工况的任务剖面下进行了评估。该评估方法为支撑电容的监测、更换、维护时间以及面向可靠性的设计提供了依据。

In the high-speed train’s traction drive system,the DC-link capacitor is an indispensable energy storage and filtering element.However,during the operation of high-speed train,the DC-link capacitor is affected by high ripple current,high ripple voltage and variable ambient temperature,so,there are huge challenges in the reliability research of DC-link capacitor.According to the characteristics of the film capacitor used in the traction drive system’s DC-link capacitor,this paper firstly analyzes the internal factors that affect the reliability of film capacitor from the physics structure,circuit structure and failure mechanism of film capacitor.Secondly,based on the calculation method of the power loss of the film capacitor,the electrical stress and thermal stress of DC-link capacitor are analyzed.Combining the life evaluation model of the film capacitor and the actual operation’s multi-conditions data that collected from the train from Guangzhou South to Changsha South,the life of the DC-link capacitor of the traction drive system is evaluated.The evaluation method provides a basis for the monitor,replacement,maintenance time and reliability-oriented design of the DC-link capacitor.