| With the rapid development of the high-speed train technology,China's high-speed railway has a relatively complete scale,and is changing from a large-scale construction stage to a full-scale operation and maintenance stage.Train health management and fault prediction?state-based maintenance technology have became a hot research topic at this stage.For the maintenance of many key components on the train,the current train maintenance strategy is still based on the traditional plan repair,inevitably there are many problems such as large quantity of inspection,unreasonable maintenance cycle and over-maintenance and so on.Accurately grasping the health status of the equipment and the remaining service life is an important prerequisite for promoting the improvement of new maintenance strategies.Taking this problem as the starting point,this thesis takes the electric connector of a certain type of EMU as the research target,and introduces the reliability evaluation method of EMU electrical connector based on accelerated test and degradation data,and deeply studies its detection method and reliability life prediction.The main research results of this thesis are as follows:(1)The theoretical methods of reliability assessment at home and abroad have been fully studied,and the maintenance strategy of the current electrical components of the EMU has been analyzed.(2)The main functions and structure of the EMU connector are analyzed.The failure mechanism and degradation mechanism of the electrical connectors of the EMU are studied and the main indicators of reliability evaluation are analyzed.Research method of reliability analysis by obtaining performance information from performance testing and accelerated testing is established.(3)Comparing with the national standard and the train standard,the performance test scheme of electric connector is studied and designed,and a series of mechanical and electrical performance tests are carried out among the electrical connectors which are randomly selected and have entered the second round of the five-level repair stage.The main failure parameters of the electrical connector are analyzed and confirmed.According to the actual engineering conditions,the accelerated test scheme is designed,and more data information is obtained by increasing the stress of the test to promote the performance degradation of the connector;(4)The reliability modeling method of electrical connector based on regression distribution is designed,and the modeling process is derived.The experimental data of electrical connector are processed by the least square and maximum likelihood estimation in mathematical method.By using the physical model and the algorithm of data processing,the life models based on Gauss distribution and Weibull distribution are established,and the remaining average service life of connectors is obtained.Compared with the model based on pseudo-failure life distribution,the reliability evaluation and life prediction of EMU electrical connectors are realized;(5)In view of the complex processing of test data and the need of strong theoretical background,and considering the actual needs of field maintenance personnel,the reliability assessment software is designed on the MATLAB GUI platform based on the modeling system of degraded data life prediction.It provides a simple and practical technical means for the field tester.Finally,the research content of this thesis is summarized,and the future research direction is prospected. |
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