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The reliabilities of the offshore wind turbine blades supported by the floating foundation are studied. The motion of the floating wind turbine is calculated by the Fast software, and the structure model of the blade is established by the Ansys software. The failure probabilities of the blade root overload, the blade root fatigue and the excessive displacement of the blade tip are calculated. The fixed wind turbine blades and the floating wind turbine blades are compared to investigate the influences of the floating foundation motion on the blade reliabilities. The results show that, the failure probability of blades supported by the floating foundation is greater than that supported by the fixed foundation. The floating wind turbine blades with different piezoelectric material are analyzed to investigate the influences of the piezoelectric material on the blade reliabilities. It is shown that for the blade with piezoelectric material, the stress of blade root and the displacement of blade tip both decrease, and the probabilities of fatigue failure and overloaded of the blade root decrease significantly.

The motions of the floating vertical axis wind turbine (VAWT) with consideration of the coupling between the aerodynamics and the hydrodynamics are calculated in this paper. The surge-heave-pitch coupling nonlinear equations of the floating VAWT are established. The aerodynamic loads are obtained by applying the double-multiple-stream tube theory with consideration of the dynamic stall and the floating foundation motion. The motion performances of a 5 MW Φ - Darrieus type floating VAWT are studied with its foundation of the Spar type with heave plates. It is shown that the amplitude of the heave motion of the floating VAWT is small when the heave plates are equipped. The effects of the wind and wave loads on the floating VAWT motions are assessed. The results show that the mean values of the surge and the pitch of the floating VAWT are mainly related to the wind loads; the standard deviations of the surge, the heave, and the pitch are mainly related to the wave loads. In the regular wave cases, the frequencies of the surge, the heave and the pitch are dominated by the wave frequencies, and the components of the 2P responses (caused by the aerodynamic loads) of the pitch are small. The 2P responses of the pitch are more significant in the irregular wave cases as compared with those in the regular wave cases.

The users and permission management functions of multiple application system will increase management complexity, reduce the convenience of users using.Analyze the module features of application system , LDAP technology , XML and RBAC technologies,etc. to build a permission centralized control system and combine with configuration file to solve the docking problems between various application systems and control systems.The system achieve unified management of users, permissions, application modules and access control and improve management efficiency and user experience.