Numerical Analysis On Crack And Fault Diagnosis Of Wind Turbine Blade

With the development of society and economy.The problem of energy consumption and pollution is becoming more and more serious.As a kind of clean energy.Wind energy is favored by governments all over the world.The blades of the wind turbine bearing the main task of rotation.The purpose of which is to transform wind energy source into electrical energy.Because of the wind turbine is often work in some remote areas,natural environment is extremely harsh conditions,the blade is in a state of suspended in the sky,once the fault for the entire wind turbine cause downtime,the generation efficiency of wind power generator is affected seriouly.It is very important to study the fault of wind turbine blades,therefore,to ensure the safety and long time running of wind turbines.In this paper,the research status of wind turbine blade fault diagnosis at home and abroad and the common wind turbine blade structure and brake are introduced.The main reasons for the failure of the blade,the type of fault,the mechanism of the fault and the common fault detection methods are compared.In this paper,the dynamic and static frequency formulas of the equivalent cantilever beam are deduced.The numerical results are compared with the theoretical results,which show the effectiveness of the finite element method.Using Wilson blade optimization method,combining with CATIA and Profili selection software,the the 3D model of the blade was established.According to the modal strain energy change rate before and after the blade damage,as the basis for the diagnosis of blade damage.Combining the two methods of modal strain energy change rate and neural network,this method has a high recognition rate and can accurately identify the blade damage.According to the analysis of the possible crack damage in different directions,different positions and different depths.The relationship between RMSD and the area of crack damage area S was established by introducing the evaluation index RMSD(mean square value)of blade health condition.Auctor plays an important role in the fault detection,the selection of the type of piezoelectric actuator and excitation frequency is very important.This paper focuses on the analysis of the influence of the dimension of the sensor and the Poisson's ratio on the resonance frequency.The results show that the finite element method can be used to simulate the damage area on the blade,which can help the selection of the key areas of the wind turbine blade failure.It is of practical significance to reduce the cost of manual labor and improve the detection rate of fault detection for wind turbine blades.Analysis of internal and external factors of resonance frequency of piezoelectric actuator for fault detection.Which is not only for the actuator structure and the choice of excitation frequency,but also provides a theoretical guidance for the optimal design of piezoelectric actuators.