State Evaluation Method Of Wind Turbine Gearbox Based On Cloud Matter Element And Improved DS Evidence Theory

The speed-increasing gearbox is an important rotating machine in wind turbines.Its role in wind turbines is to convert wind speed into high-speed rotating mechanical energy.In the event of a failure of the speed-increasing gearbox,it will have a serious impact on the normal operation of the wind turbine.Especially when the gearbox of the speed increasing gearbox is seriously faulty,the gearbox cannot be operated normally and needs to be shut down and replaced.It will directly lead to the shutdown of the wind turbine,whether it is economical or safe.More serious losses and risks.In order to ensure the normal operation of wind turbines,it is necessary to discover and eliminate possible fault factors through timely and effective fault prediction and diagnosis,and to study the state evaluation methods and maintenance strategies of wind turbine gearboxes for gearboxes and wind turbines.Operational stability and reliability are of great significance.The trend analysis of the gearbox can be used to determine the possible failure factors to achieve the forward-looking and preventive maintenance strategy.This research mainly evaluates and predicts the operating state of windturbines by increasing the speed gearbox.The contents are as follows:1.In the research of gearbox degradation degree,the construction of the degradation degree evaluation model is realized by introducing the improved CHMM model.Through the simulation of the model to compare with the actual fault type,the results show the accuracy and effectiveness of the model.The DS evidence theory is applied to the gearbox state evaluation.A new DS algorithm based on weighting method and iterative correction is proposed for the problem that the classical DS evidence theory will produce unreasonable results when the evidence is seriously conflicted.First,the credibility of each evidence is obtained by calculating the distance between the evidences.The average credibility is used as the threshold.Only the conflict evidence with the credibility below the threshold is selected for discount correction,and the remaining raw data is retained.Then merge through the classic DS evidence theory Dempster rules.Finally,the results are taken as new evidence into the next iteration until the difference between the two synthetic results is less than a certain threshold.Finally,the effectiveness of the algorithm is verified by an example.In the traditional fuzzy comprehensive evaluation method,the membership function and weight selection have strong subjectivity,and thewind turbine gearbox state evaluation model based on cloud matter element theory and improved DS evidence algorithm is established.The operating parameter evaluation parameters of the fan gearbox are selected from the current life stage and the fault hazard.Finally,the actual site data is used for calculation,and the simulation results of the fan gearbox state evaluation model based on cloud matter element theory and improved DS evidence algorithm are compared.The results show that the model is effective and accurate in comparison with traditional routines.The computational model has significant advantages over the model.In the traditional research,there are two ways to maintain the fan gearbox.The first is to maintain according to the operating state of the gearbox,and the second is to maintain according to the determined time period.Based on these two maintenance methods,a new gearbox maintenance strategy model based on state assessment is proposed through comprehensive application.Compared with the traditional single mode maintenance,it can effectively avoid repetitive work and prevent maintenance.Excessive situation occurs,based on the state preventive maintenance mode,determine the service life of different equipment components,establish a life cycle library of equipment components,comprehensively examine the operating state of the equipment system basedon the life cycle,so that the two modes are combined The aspect can reduce the cost of actual maintenance,has good economical efficiency,optimizes the maintenance level of the equipment system on the other hand,and effectively improves the maintenance efficiency.Finally,the validity of the model is verified by an example.