Optimization Of Lightning Strike Wind Turbine Blade Based On Leader Progression Model

In order to improve the economic effect of wind power generation,the development of large-capacity wind turbines has become an inevitable trend in the future wind power market.However,with the increase of power generation capacity,the height of the wind turbine and the length of the blades are bound to increase,resulting in a significant increase in the risk of lightning strikes by wind turbines.Lightning strike wind turbines will cause huge economic losses.Among all the components damaged by lightning strikes,the damage to the blades is the most serious,resulting in the highest maintenance costs and the longest downtime,which greatly affects the economic benefits of the wind power generation.Therefore,it is urgent to propose a measure that can effectively protect the blades when lightning strikes wind turbines.Using Ansoft to simulate the electromagnetic field of the blades,it is first confirmed that the tip of the blade is the easy strike point of lightning,and the metal receptor must be installed to protect it,and the body of the blade also has a certain risk of lightning strike,and additional receptors should be installed to achieve effective protection of the entire blade.According to the results of preliminary electromagnetic field simulation,five kinds of effective receptor schemes are proposed in this paper.Because of the limitation of electromagnetic field simulation,there are some unreasonable methods to judge the effectiveness of each scheme by relying on electric field intensity alone.Therefore,considering that the upward leader progress model is the closest model to the actual starting physical process of the upward leader on the blade,a wind turbine blade stroke model based on the upward leader progress model is proposed to compare the effectiveness of each scheme.Based on the space charge calculation method of potential distortion,the upward leader progress model suitable for a single tip receptors is deduced in this paper.However,through the analysis of the real leader progress conditions,it is concluded that the blades are often in a rotational state when the wind turbines are in fact,and the blades are often fitted with multiple receptors,which is easy to produce multiple upward leaders and form a competitive situation.Therefore,it is necessary to improve the upward leader progress model on the wind turbine blades according to the actual working conditions.Based on the energy balance equation of cathode flow,this paper deduces the formula of temperature calculation at the beginning of the leader on the blade,improves the upward leader progress condition,gets the blade receptors model suitable for the multi-receptors scheme,and calculates the strike distance of the receptors in each scheme by MATLAB.Combined with the electrical geometry method,according to the obtained strike distance to make the electrical geometry of each scheme,and in view of the wind turbine Blade single receptors and multi-receptors,the calculation formula of the exposure distance is calculated,the shielding efficiency of each scheme is calculated by using the calculation formula of the efficiency of the wind turbine lightning protection system,and finally the installation of 1 receptors on the tip,2 receptors on the blade scheme have the best protection effect..