| Wind energy as a clean and renewable energy, the blades of the wind turbine is one of the most critical components, The manufacturing cost of Wind Turbine (WT) blade is about20%of the cost of wind turbine.wind vane airfoil and along the spanwise, distribution design theory is to determine the underlying factors of wind turbine power characteristics and load characteristics, the paper outlining the development of domestic wind power on the basis of their leaves, the wind turbine blade loads analyzes the form and size of blade vibration control for the status quo, the proposed Finite Element Analysis of the housing while the analysis equation; the mind of a piezoelectric material embedded in the composite material constituting the blade intelligent blade, completing the design of intelligent blade; research airfoil blade housing piezoelectric Finite Element Modeling and analysis. The results with the results of the commercial finite element software Algor were compared to verify the validity of the model. Finally, the design is simple experimental system, the effect of vibration control experimental study, the main research work and achievements accomplished summarized as follows:1) introduced the current status of wind energy utilization, blade structure, materials and design, research progress of active control theory for modeling and vibration of wind turbine blade is analyzed, the application of piezoelectric intelligent material in active vibration control is introduced at home and abroad, points out the necessity of the active vibration control of wind turbine blades.2) Smart composite blade load analysis:To investigate the presence of wind turbines in the form of load, in various states of different combinations of models and wind conditions, the study load of the structure of the different calculation methods based on design conditions of wind turbine blades, and to determine the limit load conditions occur, to carry the load simulation computing research; statistical laws limit load conditions of extreme turbulence wind study models, combined with simulation results verify the feasibility study of the method leaves pneumatic fluid analysis.3) Structural design of intelligent composite blade:to build a theoretical model of wind turbine blade design power through, start wind speed, the mechanical and electrical properties of piezoelectric ceramics analysis and other parameters. Based on the coordinate transformation method and composites design ideas, get a generic method leaves modeling study leaves the main beam bearing structural stiffness, skin, etc., the strength of the design criteria. By constructing leaf analysis, using composite materials classical laminated plate theory, the basic theory of beam theory, research strength design method of composite material blade; based blade spanwise and other strength conditions, study design coordinated approach based blade displacement deformation restraint stiffness and guidelines; through reasonable simplification of the structure of the blade, blade design study fast initial structure; to1.5MW wind turbine used, for example, designed a piezoelectric smart blade and three-dimensional modeling, and thus the structural design of intelligent composite blades usefulness and accuracy of the method is validated, and lay the foundation for further analysis of the smart wind turbine blades.4) Piezoelectric composite blades and viscoelastic structural strength analysis: twisted airfoil shell itself in space, very irregular, an effective mechanical model will fundamentally solve the control effect of piezoelectric composites, numerical method of finite element method is a method wherein one of the most effective. Conducted for the composite shell finite element modeling, based HR piezoelectric material (Hellinger-Reissner) variational principle and ideological order shear deformation theory, briefly export Hamilton canonical equation operator expressions, which analyzes the relationship between the mechanical, select the appropriate representative volume element, taking into account the performance of the interfacial layer is derived and the finite element dynamic equations of piezoelectric composite piezoelectric plate and shell structures.5) The finite element analysis model of the piezoelectric shell is established with Matlab software; at the same time, the piezoelectric material is applied potential using ALgor software based on the design of piezoelectric smart composite blade model, the change of strain, displacement and stress is assessed, for judging active vibration control effect of using piezoelectric materials in FRP composite blade, in order to analyzing the dynamic load, the ANSYS command stream programming is used to analysis the blade vibration under wind load and the control voltage. The results show that:the vibration of blade under wind or random wind attenuation slowly, but, when the control voltage is applied to piezoelectric material on the blade, the vibration of blade attenuation quickly because the reverse piezoelectric effect of piezoelectric material, an electric field force, as the action force, can improve aeroelastic stability of the wind turbine blade great in extreme wind conditions.6) Intelligent Active Vibration Control of leaves, the wind turbine blade is equivalent to a piezoelectric cantilever, housing, etc., use filtering technology to solve the Kalman filter finite measurement points and predictive control, adaptive filtering control system design. Random, delay, time-varying, and nonlinear characteristics more obvious, online and in real time inspection system or run side indicators, according to changes in parameters or indicators, changing the control parameters or control action, the system’s performance to the technical requirements or optimal. During the operation, the controller according to the reference input, control elm into the object output and the known external interference performance indicators to measure the object and design of simple experimental system for verification. |
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