Study On Modeling, Load Simulation And Load Optimization Of Wind Turbine

In recent years, power and structural complexity of wind turbine are constantly increasing along with the rapid development of China’s wind power industry. The operation stability and safety of wind turbine have been paid more and more attention from research institutions to enterprises. Especially with the development of wind power in large-size, large-scale and frequent accidents in recent years, it’s needed to better understand and master system simulation and analysis technology of wind turbine, which can inspect wind turbine’s potentially dangerous under various working conditions in whole and partial level, to guide design and improve wind turbine’s operating stability and reliability. Therefore, large wind turbine’s combined simulation model should be built up correctly, then performance and movement can be analysis by simulation, dominant condition and wind resources’ leading features which influent wind turbine’ loads significantly can be researched, loads control technologies which reduce influence of environment or wind resource’s dominant characteristics can be explored, correctness to analysis methods can be verified through measurements at windfarms. All the procedures have significance to improve wind turbine’s system design level in China.According to the main research contents of National Science and Technology Support Project(2009BAA22B02) and International Cooperation Projects of the Ministry of Science and Technology(2010DFB60700),this paper focused mainly on wind turbine’s system modeling, simulation analysis and optimization. Modeling and simulation technologies in wind turbine’s simulation were researched, which were also verified through simulation using measurement datum from wind farm. Corresponding load calculation and optimization methods were formed in above process. The main research contents are as followings:①Studied wind turbine’s aerodynamic theory, structural dynamics analysis and control theory. Based on these theories, established coupled simulation model considering aerodynamics, elasticity and control. Then wind turbine’s loads calculation and performance analysis were done, model’s correctness were verified through comparison with results from GH BLADED software.②According to various conditions that might be encountered in wind turbine’s life time, defined full sets of load cases which were applicable to wind turbine’s load simulation, based on researches in wind characteristics. Based on the simulation model built, loads series were analysis for typical load case and equivalent loads were analysis for full life cycle, to analysis influence factors and loads varying rule. Studied wind turbine’s performance, especially stall phenomenon in pitch wind turbine and dynamic power curve which provide reference to evaluate wind turbine’s performance reasonably.③Studied load optimization methods. Based on characteristics of optimization object, put forward many kinds of pitch and torque control strategy to reduce extreme loads, such as pre-pitch, variable parameter and variable pitch, speed and torque’s flexible coordination control. Comparison were made for optimization results, and also been verified through measurement in wind farm. Put forward weight methods to analysis fatigue load, which could filter out load cases and loads that have important effects on equivalent fatigue loads. Wind turbine’s fatigue loads can be optimized based on the research results of this method.④Studied simulation and verify technologies of wind turbine load test. Through analysis to measurement datum in a 2MW wind turbine, combined with actual situation and simulation modeling methods, put forward methods for analysis and verify measurement datum, methods to build up analysis model for measurement wind, methods for simulation verify to measurement results. Measurement load cases were chosen to simulate and verify simulation and measurements results using coupled simulation model, deviations were given along with detailed analysis and evaluation, to verify correctness of methods to wind turbine’s loads calculation and measurement simulation. Thus formed a complete theory and method for modeling, simulation and optimization for wind turbine.