ABSTRACT
The primary problem of dynamic researching is the systematic resonance and
stability for the wind turbine. The alternate load, air driving force, inertial force and
elastic force etc that be pressed on the blade of wind turbine, can bring on coupling
vibration of the elastic blade and tower when the wind turbine works in the condition
of natural wind. If the frequency of outside force approaches the systematic natural
frequency, the resonance will be happened and arousing intense destroying for wind
turbine. Therefore, only making the systematic natural frequency keep away from the
frequency of outside force can avoid resonance.
Aimed at the configuration and operation characteristic of the modern large-scale
horizontal axis wind turbine, combining the external environment and the international
standards of wind turbine design, the load analysis method of the whole wind turbine
system is studied. The 1.5MW variable speed constant frequency wind turbine is taken
as investigation subject, the analysis method of the large-scale wind turbine dynamic
response caused by the aerodynamic load and mechanical load are investigated. In the
thesis, five parts are mainly included: system-load computing method of wind turbine,
blade's three-dimensional solid modeling and tower designing method, dynamic
computing of Bladed, the coupled rotor brandishing and tower front and back bending
system is analyzed.
Above all, the aerodynamic and mechanical loads applied on the wind turbine are
analyzed. The aerodynamic performance prediction and loading analysis are based on
the strip theory, synthesizing Moment and Blade Element theories and considering tip
loses, angle effects, solidity, wind shear, yawing effects, etc. The aerodynamic
characteristics of the rotor can be predicted accurately, and the work provides a
calculating base for the wind turbine's subsequent analysis and design.
In the chapter three, a study on the common methods used in wind blade's
three-dimensional modeling are discussed, optimal design of Blade Geometry
Parameters which can provide the basis for wind turbine's structure finite element
analysis.
In the chapter four, a method to design wind turbine tower is given. By using
ANSYS10.0, the stability analyses of 1.5MW wind turbine tower are carried out. An
analogy method for cabin, wind wheel and foundation is provided. Applying