Research On Wind Turbine Nacelle Feedforward Control And Wind Power Performance Based On Laser Wind Radar

Due to the gradual increase in human demand for energy,the requirements for energy quality and efficiency are becoming more and more stringent.How to efficiently use wind energy is a hot research topic in today’s energy field.In a wind turbine,the feedback control system controls the yaw system through the wind speed estimated from the wind wheel speed to achieve a better pitch angle against the wind and improve the efficiency of wind energy utilization.However,due to the instability and randomness of wind speed,and the turbulence caused by the front fan,this control method is variable and unstable in wind measurement,which is easy to accelerate the wear and aging of the gearbox of the yaw mechanism.Therefore,this topic mainly focuses on the research of the feedforward control of the wind turbine nacelle with the lidar technology.The laser wind measurement radar can stably measure the wind speed within 200m in front of the wind turbine head and can predict the wind speed in advance.Through feedforward control,the wind turbine yaw mechanism and the feedback control system jointly control the wind turbine pitch angle to achieve more Accurate wind,improve the utilization efficiency of wind energy,and solve the problems of wear and aging of the wind turbine gearbox.The paper uses five chapters to study the feedforward control and wind power performance of wind turbine nacelles based on laser wind radar.The main research contents of the paper are as follows:In this paper,a mathematical model of the feedforward control mechanism and the correction method of Lidar wind measurement is established,which is convenient for subsequent analysis of theories and calculation examples.A model for selecting wind measurement points by lidar is proposed.Starting from the type of lidar,it is proposed to select 10 wind measurement distances(wind measurement planes)starting from the wind turbine head and select 4 wind measurement points for each plane.The wind measurement points are analyzed by mathematical modeling,the wind speed model is introduced,and the wind speeds of different wind measurement points are unified by the linear least square method,and the equivalent wind speed within each wind measurement distance is calculated,and then the integral mathematical model is used to All wind measurement planes are integrated to obtain the equivalent average wind speed within 200m in front of the wind turbine head.The calculation method of the power curve is introduced.Data standardization is required for the analysis of the case.Introduced the uniformity of the flow field and the influence of the cabin environment(heating problem)on the wind turbine,and proposed solutions.According to the model proposed above,combined with the actual measured wind speed and wind turbine pitch angle,and rotational speed data,the calculation example is analyzed.This chapter first strictly restricts the test model,method,process,site,etc.,to ensure that it is carried out with the least influence of irrelevant variables.Analysis and testing procedures include the main system at the bottom of the tower,the hub system,the top system,signal acquisition software,and data analysis software to meet IEC standards and international third-party certification requirements.First,analyze the blade root and the bottom of the tower.These two parts are the most representative key positions of the wind turbine.The load level of the blade root and the bottom of the tower can reflect the magnitude of the load at the two key positions and can be well reflected.The load level of the entire unit.Secondly,discuss the operating status of the wind turbine under severe wind conditions,consider the wind turbine braking system,and introduce the lidar as the feedforward control yaw system,and the instantaneous wind speed,wind direction,and wind shear generated under the influence of various complex factors As well as the effect of changes in turbulence on the overall load of the wind turbine.whether the wind turbine can operate safely and stably under severe wind conditions is discussed.Finally,discuss the wind turbine pitch and the safety and stability of the unit,and discuss whether the introduction of lidar can reduce the load of the pitch system,that is,the pitch bearing and other key driving and safety components.Finally,summarize the research content of this article,put forward the innovation points of this article in engineering application,and the actual value of the innovation points,summarize the effect of this article on the wind power load and wind power improvement after the introduction of laser wind radar as feedforward control,and combine the actual And the prospects of wind energy utilization,discuss the application prospects of this technology.Summarize the shortcomings of the conclusions put forward in the paper,and put forward the next research ideas.