Research Of Test Bench For Wind Turbine Main Bearings

As one of the new energy technologies,wind power have changed the original energy structure.Since it is safer than the traditional power generation forms,more and more countries develop their experimental researches on wind turbines successively.For the matching bearings of high-powers over 1.5MW,the technical problems of bearing design,process,manufacturing,detection,test and so on increased due to the increasing of bearing product size.The bearing industry in China is limited by imperfect test standards,test procedures and relatively backward product development concepts,resulting in the lack of synchronous research on bearing basic theory and test methods in the product development phase.Thus,it would have great significance for the technical development of wind turbine bearings in China if we are able to establish the basic theory of wind turbine bearing,develop a special bearing test system of large wind turbine,gradually have the ability of performance simulation test and life test for bearings of 1.5-3mw large wind turbine.This paper is focus on developing a special test system for bearings of large wind turbines with independent intellectual property rights.Through this test system we are able to both set up a special test standard and build a basic database for large-scale bearings,also,we can carry out computer simulation virtual design and optimization analysis,determine the load spectrum of wind turbine main shaft bearings.Finite element simulation method was adopted to build a three-dimensional model of this test system with three-dimensional software.Then the strength and deformation of the wind turbine main shaft bearing test system was analyzed by grid division,boundary conditions and load conditions of the three-dimensional model,and got the result that both strength and deformation of this test system are able to meet the actual test conditions.Next,we optimized the design and avoiding some design defects after analyzing the shaft and box vibration mode,frequency and other results of the test system.Through matlab,we are able to comprehensively & statistically analyze the load spectrum of bearings for same type of wind turbines,in same position,or in same specification.Then,according to the time ratio of each load or load section,especially the joint probability density distribution of peak load,mean load and action time of load spectrum,we can infer the possible influence of bearing load spectrum on bearing strength and life.By classifying a large number of similar bearing load spectra into a small number of typical bearing load spectra and add to the original data database,we are able to simulating the actual operation conditions of the main bearing for wind turbines to largest extent,forecasting the service life and failure mode of the bearings by the loading test of the main bearings,and providing powerful data support for the product design optimization and manufacturing process control of the main bearings of the wind turbines.Promoting main bearing accuracy,to meet the demand of high safety,high reliability,long service life and high environment adaptability for main bearing of the wind turbine.To accelerate the localization process of wind turbine main bearings eventually.