Research On Maintenance Strategy Model Of Offshore Wind Turbine Based On Opportunity

Compared with onshore wind power,offshore wind power has the advantages of high average wind speed and high annual utilization hours.In recent years,offshore wind power has become an important field of wind power industry development.However,due to the special operation environment of offshore wind power,the maintenance of units is restricted by accessibility,waiting time and other factors,and the related maintenance theories and strategies are prominent.China’s offshore wind power technology started relatively late,and the operation data and maintenance experience are relatively scarce.Strengthening the research on the maintenance strategy of offshore wind turbines can provide reliable technical support for the follow-up large-scale offshore wind farm construction and unit operation.To solve above problems,this paper analyses the characteristics of operation data of offshore wind turbines,and studies the reliability analysis method of offshore wind turbine based on small sample fault data.Combined with the influence of weather factors such as sea wind speed and wave height,the maintenance waiting time prediction method of offshore wind turbines is studied.Based on the analysis of the principle of equipment opportunity maintenance strategy,an opportunity-based offshore wind turbine maintenance strategy was proposed.The main results of this paper’s research work and achievements are as follows:(1)Study the reliability analysis method of offshore wind turbine based on small sample.This paper studies the construction of Weibull equation for offshore wind turbines based on small sample fault data.On the basis of explaining the construction of two-parameter Weibull equation of least square method and maximum likelihood method,three-parameter Weibull equation of correlation coefficient method and bilinear regression analysis method are proposed.Taking an offshore wind farm in Jiangsu Province as an example,based on the small sample fault data of wind farm,the parameter estimation of Weibull equation of generating units is carried out,and a comparative analysis is made.The results show that the fitting of three-parameter Weibull distribution is better,especially the short-term prediction of wind turbine failure rate is more accurate.(2)Study the prediction method of maintenance waiting time for offshore wind turbines.In this paper,the dynamic time window and Markov chain method are used to describe the weather factors such as sea wind speed and wave height,and the wind turbine maintenance waiting time prediction model is established.The results show that the predicted value of the wave height obtained by grouping interval with AHs=0.1 m is the smallest,and the waiting time of the group is the closest to the true value.In addition,the wind speed and wave height data of an observation station in the Yangtze River estuary of the East China Sea are taken as examples to verify the correctness and effectiveness of the model.(3)Study the opportunity-based maintenance strategy for offshore wind turbines.In this paper,the opportunistic maintenance strategy for offshore wind turbines is studied based on the fault maintenance and preventive maintenance of the equipment.Through the analysis of maintenance opportunities for key components of the unit,the objective function is to minimize the maintenance cost in the cycle,so as to realize the opportunistic maintenance of key components of the unit.The results show that the maintenance cost is reduced by 10%under the opportunistic maintenance strategy,which verifies the effectiveness and superiority of the opportunistic maintenance strategy for offshore wind turbine maintenance.