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In recent years, wind energy has become the mainstream of the new green energy devel-opment. Large-scale wind turbine is a complex flexible multi-body system, and the coupling among components and their dynamic characteristics have become the research hotspot re-cently. At present, the technology concerning increasing or decreasing blades windward by the active or passive control of pitch angle, has become mature, but active or passive control of the blade length draws litter concern. In this paper, the static and dynamic performances of wind turbines with coning rotor based on the blade length control are analyzed and studied, and the bionic design of plant flexible system with the property of windshield is explored pre-liminary.Based on the flexible hinge design method of dynamics system theory of wind turbine with coning rotor, flapping and pitching stability of rotor/tower system are analyzed by the analytic and example validation method. The results show that, compared with the undamped system, the coupling area increases, and the vibration of the system moderates in the damped system, but without unstability. Then, the finite element model of a 1.5MW wind turbine blade with coning rotor, is built, and the influence factors of power output and its static and dynamic characteristics are analyzed. The static analysis results show that the strength and rigidity of wind turbine parts, such as the blades, hinge and tower, are all in allowable range under the load cases of gravity, centrifugal load, air pressure and resultant load. The stability analysis results indicate that the tower is flexible, the system is stable and safe at the normal working condition. And in view of the main influencing factors of system stability, the low-er-order natural frequency of tower can be increased by reducing the radius and thickness of tower top to make sure that the tower strength is enough, which could make the wind turbine machine not only avoid the resonance, but also save material and enhance the flexibility of tower. The transient response results show that,under the extreme operating gust, the com-ponent response of wind turbine with coning rotor changes periodically, and the coupling stiffness among blades, nacelle and tower has an important effect on the component response. According to the working mechanism and wind-resistant advantage of the coastal plants royal palm, as well as both the similar configuration and stress environment with coning rotor, the royal palm characteristics have been investigated. First of all, the experiment of the me-chanical properties about plant is carried out, and the microstructure and mechanical characte-ristics of each part of the plant is analyzed. Then, a taper cantilever model is established, and the strength and stiffness under the different angles are analyzed. The results show that the comprehensive performances, such as stiffness and strength, are the best when the branch an-gle is near 60°. Finally, according to the collected experimental samples, the geometric model of the palm tree is established, and the static dynamic performance of the structure is ana-lyzed. The results indicate that the different branch angle affords different deformation and stress, and the stiffness distribution of leaf shell has a great influence on the deformation and stress of petiole. The natural frequency analysis results show that the mode shape of the sys-tem is similar to the wind turbine with coning rotor, which laid a foundation for the bionic de-sign of wind turbine with coning rotor.
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