【作者】 李兵；

【导师】 鄂明成；

【作者基本信息】 北京交通大学 ， 工业工程， 2017， 硕士

【摘要】 近年来随着我国经济飞跃发展和社会需求的提高,高速铁路进入了全面发展时代,高铁运营里程和动车组数量不断增加。极大地提高了我国铁路客运能力,给社会带来了巨大的经济效益和社会效益。越来越多的动车组投入使用,对动车组在役安全和科学有效的维修管理提出了更高的要求和挑战。车轮作为动车组最重要的部件之一,更是维修研究中的重中之重。车轮在运行过程中,与轨道不断接触,造成轮缘和踏面难以避免的磨耗,对整个动车组的行车安全及稳定性产生威胁。为了恢复车轮的正常几何尺寸和确保动车组的运行安全,必须对磨耗车轮进行镟修或更换。然而,镟修会导致车轮材料的减少和维修成本的增加。如果镟修量过大会导致车轮过早报废,镟修量过少导致镟修成本增加。因此,"何时镟修,镟修量多少"成为车轮镟修策略制定中亟待解决的关键问题。针对该问题,本文提出一种基于车轮周期状态检测信息的动态镟修策略,降低车轮维修成本,延长其使用寿命。首先通过对某编组车轮测量数据的统计分析,确定踏面直径和轮缘厚度磨耗速率的分布,揭示动车组车轮踏面和轮缘磨耗规律。同时,根据镟修结果数据的统计和分析,确定镟修比例系数的分布规律,为后续车轮镟修策略的研究奠定基础。接着,在上述研究的基础上,将车轮踏面直径和轮缘厚度的退化过程离散成有限的退化状态,建立二维状态空间,以单位期望成本最低为目标,构建基于SMDP的镟修优化模型,并采用策略迭代算法对模型求解。然后,综合考虑磨耗和外部冲击对车轮退化过程的影响,构建了基于失效阈值冲击模型和SMDP的镟修优化模型。最后,在上述建立的磨耗分布和镟修比例系数分布基础上,根据某编组动车组车轮的实测数据,将本文提出的动态镟修策略与固定镟修策略作比较,验证了提出的动态镟修策略的有效性。更多还原

【Abstract】 In recent years,with the rapid development of China’s economy and the improvement of social needs,high-speed railway is going into a comprehensive development era.The number of high-speed rail operations mileage and EMUs increases.It greatly improves the railway passenger transport capacity of China.It also has made tremendous economic and social benefits.Meanwhile,as more and more EMUs put into use,it puts forward higher requirements and challenges for the maintenance and management of the EMUs in service and effective maintenance.As one of the most important components of the EMU,the wheel is the most important part in maintenance research.The wear of wheel’s tread and flange is unavoidable due to the touching with track when moving,which threatens the safety and stability of EMU in service.To avoid performance degradation because of wear and ensure the safety of EMU,the wheel must be reprofiled or replaced.However,these processes generate significant material waste and high maintenance cost.With more recovery of the flange,the wheel must be replaced sooner.With less recovery,more maintenance cost increases due to re-profiling activities.Thus,the threshold of re-profiling activity and the recovery of the flange should be optimized,which is the key to make the re-profiling policy.To balance the threshold and recovery of the re-profiling activities,a dynamic re-profiling policy based condition monitoring at equidistant discrete time epochs is proposed.The policy can not only reduce the maintenance cost,but also extend its service life.Firstly,the wear rate of the tread diameter and flange thickness is determined based on the statistics and analysis of the wheel measurement data of a certain EMU,which reveals the wheel tread and flange wear law.Meanwhile,the distribution of re-profiling gain is obtained based on the result data of re-profiling activities.These research findings lay foundations to optimize the re-profiling policy.Secondly,to build the state space,the degradation process of the tread diameter and flange thickness is divided into finite degradation states.With the object of minimizing long-run expected maintenance cost per unit time,the re-profiling optimization model is established which is based on the semi-Markov decision process.We apply a policy-iteration algorithm to determine the optimal re-profiling policy.Thirdly,considering the influence of external shock and wear on the degradation process of tread diameter,the re-profiling optimization model is built,which is based on degradation threshold shock model and semi-Markov decision process.Finally,we combine the proposed policy with the fixed re-profiling policy based on the wheel measurement data of a certain EMU to demonstrate the method’s effectiveness.更多还原