Research On Wind Speed Model And Its Influence On Power Curve

Wind energy, as an increasing way of renewable energy power generation, which is clean, sustainable and easy development. However due to turbulence of wind characteristic, it is determined that wind turbine suffers disturbance of load as well as the volatility of output power. In order to improve the accuracy of the wind turbine model, and to ensure the stable operation of power system, a wind speed based on real wind condition is in need.Based on Kaimal turbulence spectrum from IEC61400-1 (2005) version and wind speed Weibull probability distribution, a combined wind speed model is set up, aiming at describing the randomness and volatility of wind speed and also meet long-term statistical properties of actual wind speed. Then, it was applied to the analysis of power curve under different turbulence intensity, aiming at studying the effect of wind turbulence characteristics of power curve.Main work content is as follows:(1) Sum up various characteristics of wind speed, use 5 methods to evaluate Weibull parameters and 3 methods to select the optimum solution, choose Kaimal spectrum as the turbulent wind model.(2) A combined wind speed model based on real wind data and Kaimal spectrum is established, the probability of different wind speed(from cut in speed to cut out speed) duration is calculated by Weibull distribution, turbulence intensity of each wind speed are figured out either. Results cover all wind speed type.(3) Correction of wind speed model. Since Kaimal spectrum simulation for each wind speed adopt an average turbulence intensity value, which shows the probability density can’t fit Weibull distribution ideally. Therefore, two methods of turbulence intensity partition and ARMA model were executed.(4) Analysis of influence on power curve with wind speed model. Power weight analysis method is put forward, results show that when turbulence intensity is between 3%～11%, the weight of power and dynamic power is less than 1.5%, when turbulence intensity in 0～3%,11%～15%, the weight is in range of 3.1%～3.5%, when turbulence intensity in more than 15%, the weight is more than 6%.