Research Of Wind Turbines’ Measurement Of Mechanical Loads Based On IEC Standard

This thesis mainly investigates relevant theoretical issues involved in themechanical load measurement of the wind turbine based on the IEC61400-13international standard and develops a professional application of the measuredmechanical load data processing system which is very significant to the nationalizationof wind turbines’ measuring technique.The subject belong multidisciplinary engineering, so it’s necessary to make a clearand concise introduction to the background knowledge in which the subject is involvedthrough sorting a large number of relevant background information, including theworking principle of the wind turbine, the determination of mechanical load of windturbine key components, the development status of wind turbine certification and testingfield home and abroad, the wildly used IEC61400-13international standard for testing,etc. This thesis aims to offer many theoretical references and valuable practicalexperiences to the research of wind turbine mechanical load measurement and form amature wind turbine mechanical load measuring technology to realize reliable andeffective load measurement with lower cost.In this thesis, measurement techniques of the wind turbine mechanical load aredeeply and extensively studied, including the determination of measured values, the testprinciples and methods of every measured value, the sensors adopted and theircalibration and inspection in the measuring process, etc. Requirements of wind turbineoperation status in the test process and establishment of relevant capture matrix areinterpreted in detail. The verification methods of testing data and the correction ofabnormal signals are summarized according to the long term test experience. Thetraditional fatigue analysis approaches of mechanical components are deeply studied,and then applied to the fatigue analysis of the wind turbine which facilitates thecompilation method of fatigue load spectrum and the calculation method of equivalentloads.The professional wind turbine mechanical load test data processing system isdeveloped with complete data processing and analyzing ability based on IECinternational standard, including the original10-minute data calibration, statistical datageneration, data validation and correction, capture matrix establishment, equivalentloads calculation, load statistic reports, various curves and charts specified in the IEC specification of the load statistics reports and fatigue load spectrum.In order to verify the efficiency of the test data processing system, from December2010, nearly5months data from Guanting Wind Farm located in Beijing is processed.The whole load measuring process, data processing procedure and partial analyticalresults are supplied in this thesis so as to help to deepen the understanding of the IEC61400-13international standard. Final comprehensive comparing results indicate thatthe results obtained using this processing system show acceptable agreement with thosegiven by the well-known international wind turbine certification authority Windtest.