Research On Wind Turbine Blade Damage Detection Based On Infrared Thermal Imaging Technology

Wind turbine blades are one of the most important components of wind turbines.They carry the important role of capturing wind energy and energy conversion.Their safety and reliability are important guarantees for the stable operation of wind turbines.With the rapid development of the wind power industry,the quality level and healthy operation of wind power systems,especially wind power blades,have received increasing attention from the society.Different types of defects and damages will occur during the production,transportation,installation and operation of wind power blades,increasing the operational risk of wind turbines.Therefore,a quick and efficient means of detecting damaged wind turbine blades is essential.At present,the detection of wind turbine blades in service mainly uses periodic ground manual inspections such as telescopes or bird watching mirrors,and periodic shutdowns for manual hanging orchid maintenance.The detection is inconvenient,inefficient,and greatly affected by the level of the operator,and cannot be effectively detected Damage inside wind turbine blades.With the development of modern industry and science and technology,non-destructive testing technology and non-destructive evaluation technology play an important role in the process of product quality control and in-service testing of equipment in operation.Infrared thermal imaging non-destructive testing technology has the advantages of non-contact,large-area testing,intuitive results,simultaneous surface and subsurface testing,etc.,and has received high attention internationally in recent years.However,at present,most researches on infrared thermal image detection of wind power blades in China are limited to laboratories,and there are few related researches applied to field inspection of wind power blades.In response to the above problems,this paper carried out the following research:In the autumn of Inner Mongolia,under the excitation of natural conditions in the outdoor environment,passive infrared thermal imaging technology was used to perform 2kW wind power blades with three artificial damages:wear,cracks and internal glue The detection test was carried out.By analyzing and summarizing the thermal characteristics of the three damages in the original infrared thermal image obtained,the suitable detection conditions for infrared thermal image detection of wind turbine blade damage were classified and summarized;and the experiment was tested using COMSOL Multiphysics Numerical simulation was carried out in the process,and established a correct numerical simulation model for the subsequent experiments.The results show that:Passive infrared thermal imaging detection of solar radiation as an excitation source under natural excitation can be used for damage detection of wind power blades.In autumn testing in Inner Mongolia,the suitable detection conditions for the three typical damages of wear,cracks and internal adhesion are summarized as follows:the damage of surface wear type can be effectively detected when the solar irradiance reaches 200～700 W/m2 during the day time;the damage of the surface crack type can be effectively detected when the solar irradiance reaches 400～700 W/m2 in the afternoon;the damage of internal adhesive type can be effectively detected when the solar irradiance reaches 600～700 w/m2 in the noon or when the solar irradiance reaches 0～100 w/m2 in the evening.