Imperfect Maintenance Strategy And Game Analysis Of EMU Equipment Based On Reliability

The operating mileage of high-speed railway in China has exceeded 4×10~4 kilometers by the end of 2021,and the number of Electric Multiple Units(EMUs)has reached 4153 standard units.Therefore,ensuring the safe and reliable operation of EMUs is a major issue for the railway operation and maintenance departments.At present,our country implements the periodic scheduled preventive maintenance(PM)strategy for EMUs which belongs to the periodic maintenance mechanism.When the running mileage or time of EMU reaches a certain value,corresponding maintenance measures shall be taken for them.However,reliability centred maintenance strategy is increasingly used in the current production equipment maintenance field,which determines the maintenance interval,maintenance level and maintenance content of production equipment based on the real-time prediction and evaluation of equipment status.Compared with the planned PM strategy,it is a more scientific maintenance mechanism.Therefore,reliability centred maintenance strategy is introduced into the field of EMU maintenance in this dissertation,and the PM strategy theories of EMU equipment are studied as follows:(1)Based on the current periodic maintenance mechanism in the field of EMU maintenance in China,the methods to determine the maintenance interval and maintenance times of EMU equipment under the bi-level maintenance mechanism are studied.Under the condition that there is only one imperfect maintenance mode,decides on the periodic PM schedule of EMU equipment.Taking lowest maintenance cost rate within a life cycle of EMU equipment as optimization objective,and taking maintenance mileage interval and maintenance times as decision variables,the PM schedule within a life cycle of EMU equipment is optimized,so as to obtain the optimization results of PM mileage interval and PM times that make the maintenance cost rate lowest.(2)In order to overcome the objective law that the periodic PM strategy ignores the decreases of equipment performance with the increases of operating cycle,the bi-level imperfect maintenance strategy of EMU equipment based on reliability is studied.Under the condition that there are two imperfect maintenance modes,decides on the variable cycle PM schedule of EMU equipment.Considering the characteristics of failure rate increasing factor and service age decreasing factor,the hybrid failure rate evolution rule is adopted to describe the failure rate of EMU equipment.The bi-level imperfect maintenance strategy is adopted for the maintenance of EMU equipment,and the specific mode of each maintenance is determined by cost-effectiveness analysis,so as to improve the cost-effectiveness economic of EMU equipment maintenance management.(3)To improve the maintenance economy of EMU equipment in further,the opportunistic maintenance strategy of EMU equipment based on bi-level imperfect maintenance mechanism is studied.Based on the bi-level imperfect maintenance mechanism,the connotation of opportunity maintenance is expanded from opportunity advance to opportunity advance and opportunity delay,which enriches the connotation of opportunity maintenance.Under the bi-level imperfect maintenance mechanism,the lower level maintenance measures of EMU can not only be implemented in advance due to the same level or higher level maintenance measures,but also can be implemented in delay due to higher level maintenance measures,so as to reduce the shutdown times and total maintenance cost of multi-equipment system of EMU.(4)In order to make the PM strategy of EMU equipment more in line with the actual situation,based on bi-level imperfect maintenance mechanism,the multi-level imperfect opportunity maintenance strategy of EMU equipment is studied.Under the condition that there are multiple imperfect maintenance modes,the concept of opportunity maintenance is introduced to decide the preventive opportunity maintenance(POM)plan of EMU equipment under multi-level imperfect maintenance mechanism.By expanding the imperfect maintenance mode of EMU equipment from bi-level to multi-level,and quantitatively analyzes the improvement degree of different imperfect maintenance modes on the failure rate of EMU equipment.At the same time,under multi-level imperfect maintenance mechanism,the connotation of opportunity maintenance is enriched in further,so as to achieve the goal of reducing the shutdown times and total maintenance cost of multi-equipment system of EMU.(5)In order to balance the interests between operation sector and maintenance sector in better,the PM decision-making model of EMU equipment based on non-cooperative game theory is established.Based on Stackelberg non-cooperative game theory,with the operation sector as game leader and the maintenance sector as game follower,the game issue of EMU equipment under multi-objective optimization model is studied.As the game leader,operation sector has the priority decision-making rights for the goal that both of them are expected,as the game follower,the decision-making results of maintenance sector will be constrained by game leader.From the perspective of non-cooperative game,this dissertation reveals the decision-making behaviors between operation sector and maintenance sector,so as to provide theoretical reference for achieving balance between them.This dissertation explores the periodic PM strategy of EMU equipment to the reliability centred maintenance strategy,gradually extends from bi-level maintenance mechanism to bi-level imperfect maintenance mechanism and then to multi-level imperfect maintenance mechanism,expands from equipment-level PM optimization to system-level POM optimization,and the interests between operation sector and maintenance sector are analyzed by introducing non-cooperative game theory.The research work of this dissertation will promote the transformation of EMU equipment maintenance theories from qualitative analysis to quantitative calculation,which are conducive to the enrichment and development of EMU equipment maintenance theories in China,and can provide theoretical and technical supports for the application research of modern maintenance theories in the field of EMU equipment maintenance.