Study On Power Characteristics Of Wind Turbine Under Icing Condition

As the clean and pollution-free energy source,wind power has been paid attention to by the countries all over the world with good economic and social benefits.However,the rapid development of wind power has also brought a series of problems.For example,the wind farm in high-altitude area was affected by low temperature will cause the wind turbine blade getting icing,which will change the shape of the blade and change the blade surface distribution of flow field,thus affecting the utilization efficiency and output power of wind turbine.Therefore,it is necessary to study the icing wind turbine’s influence on the output power,which is very important to the anti-icing and deicing ability,and the improvement of the annual electricity consumption of the icing wind farm.At present,the research on the wind turbine focus on two-dimensional simulation of miniature wind turbine,three-dimensional research is less in the simulation phase,the three-dimensional verified experiments is relatively few,even less the experimental research on large wind turbine.This paper focuses on the 3D simulation of 300 kW wind generator under different icing conditions,which is different to the other huge amounts of two-dimensional simulations.Based on 300 kW wind turbine icing test platform which has been built on Xuefeng Mountain icing test base,this paper is mainly aimed to conducting three dimensional simulation of wind turbine which rated power is 300 kW at different icing conditions.Using Fluent software simulating and calculating the output power and torque influence on wind turbine of wind speed,rotation speed,and pitch angle under different rime and glaze degree,Finally,the paper verifies the power curve and torque curve of wind turbine under natural icing environment in the Xuefeng Mountain test station.The following conclusions are found:(1)The paper which is based on the multiple reference frame model(MRF)calculates the stationary and rotating domains of the wind turbine by using fluid mechanics software Fluent,and gets the effect of clean blades,different rime ice extent and different glaze icing degree on the wind turbine output power and torque.We also use Xue Feng Mountain natural icing test base to verify computational results,the results show:the calculated results are the same law of change as the experimental results and have good consistency.(2)The higher of wind velocity is when blade is covered with rime icing,the greater the output power of wind turbine is.When the wind turbine blade is covered with icing degree of 10%,its output power is decreased by about 13%,when the icing degree is 20%,the output power of the wind turbine is decreased by 39% compared with that of non-icing.With the increase of icing,the output power of wind turbine will continue to decline.When we keep the pitch angle and wind velocity as a constant,as the rotation speed increasing,there will appear an inflection point with torque increasing.The larger the pitch angle is,the smaller the output power and torque of the wind turbine is.(3)The higher of the wind velocity is when blade is covered with glaze icing,the greater of output power and torque of wind turbine is.When the pitch angle and rotation speed are constant,the wind velocity increases to a certain extent,and then remains stable.When the ice degree is 5%,The output power of wind turbine under rated wind velocity decreases 36.8% compared with non-icing.When the ice degree reaches 10%,The output power of the wind turbine decreases 50% under the same conditions,it’s a large drop;The larger the rotational speed is,the greater the output power and torque of the wind turbine is.With the increase of pitch angle,the output power and torque of wind turbine show a decrease trend.(4)The glaze icing of blade change the flow distribution of the blade surface and destroy the boundary layer due to irregular icing type,When glaze icing is heavy,It even appears separation vortex,the separation vortex will furtherly disturb the flow field around the blade,and then cause the reduce of wind turbine output power,So the influence of glaze icing on the output power and torque of wind turbine blade is more serious than that of rime icing.