The Study On The Aerodynamic Characteristics And The Operating Characteristic Of Variable-speed Pitch-regulated Wind Turbine

With the energy and environmental problems increasing, wind energy receivesconsiderable attention from the world as renewable clean energy. Because of highefficiency of utilizing wind energy and smooth power output, variable-speedpitch-regulated wind turbine has become the main direction in research anddevelopment in the future. In the complex operating situations, the changes of thereal-time wind speed lead to the real-time changes of the operating state of the windturbines. The proper control strategy should be designed on the basis of the study on theaerodynamic characteristics of wind turbine，so as to keep the wind turbine operatingnear the optimum operating points. Therefore, it is of important significance to study onthe aerodynamic characteristics and the operating characteristic of variable-speedpitch-regulated wind turbine.In this paper, aerodynamics characteristic of the low speed airfoil are analyzed.Rotor parameters of1.5MW wind turbine are designed and aerodynamic characteristicsof this wind turbine is discussed. Based on the aerodynamic characteristics,corresponding control strategies is designed to study the operating characteristic. Themain research work of the paper is as follows:①Theodorsen Method is introduced to study the arbitrary airfoils and obtain theresearch methods of studying the aerodynamic performance of arbitrary airfoils. Thenrelated data such as lift coefficient and drag coefficient of arbitrary airfoils is obtained.②Based on the blade element momentum theory，the computing method ofinduced wind factor，torque of rotor，thrust， and power coefficient is deduced.Considering various factors which influence the aerodynamic performance of windturbine，the relatively accurate rotor calculation model is established.③Rotor parameters of1.5MW wind turbine are designed. According to thechange of relevant parameters (wind speed, the yaw, pitch, azimuth, etc), theaerodynamic characteristic curve of wind turbine is obtained. The correspondingpractical control method of wind turbine is obtained.④The Auto-Regressive method is used to simulate the real-time wind. The generalmethod of acquiring optimum operating points of variable-speed pitch-regulated windturbines at low and high wind speeds is respectively discussed. The correspondingcontrol strategy is applied to keep the wind turbine operating near the optimum points, so as to capture maximum wind energy at low wind speed and to limit the over highpower at high wind speed. Finally, the real-time operation load spectrum is obtained andbriefly analyzed according to statistics and correlation.