城市轨道交通双向变流器供电系统可靠性预计研究

Reliability Prediction of Bi-directional Converter Power Supply System for Urban Rail Transit

为了提升城市轨道交通双向变流供电技术应用的可靠性和安全性,文章基于双向变流器的功能逻辑和任务要求,针对无冗余结构、“1+1”冗余结构和“4+2”冗余结构这3种设计方案分别建立可靠性评估模型,并结合相似产品法进行了基本可靠性和任务可靠性预计。结果显示,3种方案中两套双向变流机组并联使用方案的可靠性综合指标最佳,基本可靠度对应的失效率为5.24×10-5,任务可靠度在20000 h时为0.9893。基于可靠性预计结果,文章针对最优方案中的薄弱环节提出了可靠性提升方案,预计可将20000 h时的任务可靠度从目前的0.9893提升至0.9993。

In order to improve the application reliability and safety of urban rail bi-directional converter power supply technology,it is necessary to carry out forward quality design,and to model,analyze and compare the reliability of different design schemes.Based on the function logic and task requirements of bi-directional converter,this paper establishes reliability evaluation models for three schemes including the non-redundant structure,the"1+1"redundant structure and the"4+2"redundant structure,respectively.It further forecasts the basic reliability and task reliability combined with the similar product method.The predicted results show that the comprehensive reliability index of the scheme with two sets of bi-directional converter units in parallel is the best.The failure rate of basic reliability is 5.24×10-5,and the mission reliability is 0.9893 at 20000 h.Finally,based on the reliability prediction results,this paper proposes a reliability improvement scheme for the weak links in the optimal scheme,which is expected to improve the mission reliability at 20000 h from 0.9893 to 0.9993.