Research On Reliability Analysis And Maintenance Strategy Of Wind Turbine Based On Random Failure Rate

Since the beginning of this century,the wind power operation and maintenance industry has been continuously transforming from extensive to lean and discontinuous to continuous with the development opportunities and challenges.With the rapid growth of wind turbine installed capacity and continuous improvement and renovation of the system,the fault law of the wind turbine has become increasingly complex,which puts forward higher requirements for the reliability analysis and preventive maintenance strategy of the wind turbine.Therefore,on the basis of studying the reliability analysis and maintenance strategy status of wind turbines at home and abroad,this thesis mainly studies the reliability analysis,important component reserve and maintenance strategy optimization of wind turbines based on random failure rate.The specific research contents and methods of this thesis are as follows:(1)The stochastic differential equation(SDE)about the random failure rate of the system is established based on the random process.The basic failure rate function combined with the exponential model and the linear model is solved by using the gray linear regression model.Wind turbines fault model based on multiple linear regression to solve the wind turbines total failure rate and failure rate of components of the relationship among the expressions which the accuracy is verified by an example.With time-based maintenance(TBM)and the combination of condition-based maintenance(CBM)as the research object,a physical system by establishing a state transition diagram and vector markov process,and get partial calculus expression,Laplace transform is used to calculate the reliability index of the system,and for the system of TBM and the general law and characteristics of CBM.Aiming at the existing multi-state repairable equipment,the multi-state transfer diagram and the multi-state transfer random differential equation matrix were established,and the corresponding reliability index expressions under different maintenance modes are solved.The reliability analysis of the whole and partial parts of the wind turbine is carried out.(2)Reserve the important parts that need to be stored in advance during the maintenance of wind turbines based on the principle of importance,so that the storage cost of spare parts can reach the optimal utilization level accordingly,so as to optimize the maintenance configuration.The purpose is to achieve a good balance between the storage of expensive maintenance spare parts and the required amount of maintenance,reduce the extra maintenance cost of wind turbines,so as to solve the contradiction between storage and demand of maintenance.(3)Finally,the inspection rate is considered as the optimal maintenance strategy of progressive failure rate combined with CBM and TBM.Simulation results with Matlab show that the combination of TBM and CBM can effectively improve the failure rate of the system.The maintenance strategy of wind turbine based on random failure rate is proposed,which is both combined CBM with TBM and complete with incomplete maintenance.It not only ensures the reliable operation of units and components,but also establishes a cost model to minimize the cost of maintenance so as to realize the optimization of maintenance decision.