If the vibration is large during normal power generation, it is likely that the main transmission chain (such as main bearing, gearbox and generator) has a mechanical failure, such as bearing wear or damage, high-speed shaft misalignment, loose anchor bolts, power generation It is caused by loose copper bars of the rotor or unbalanced fan blades. It is recommended to find domestic professional companies such as Beijing Hanergy Technology, Goldwind Tianyuan and other companies to conduct a comprehensive vibration detection. It is best to use a multi-channel synchronous acquisition system, so that the cause of the fault can be found in about half an hour at a time. Early action can avoid serious failures. One of the wind farms of our brother company was vibrating so much that the coupling flew off. What a danger!
Wind turbine blades account for about 15%-20% of the total cost of the wind turbine. At present, the blades of large wind turbines are basically composed of composite materials, and the composite material content usually exceeds 90%. According to statistics, every 6% increase in the size of wind turbine blades can increase the amount of wind energy captured by 12%.
The original intention of the blade design is to achieve a balance between dynamic efficiency and structural design. The choice of materials and processes determines the final actual thickness and cost of the blade. Structural designers play an important role in how to combine design principles and manufacturing processes, and must find the optimal solution between ensuring performance and reducing costs.
Blade force analysis: The thrust on the blade drives the blade to rotate. The distribution of thrust is not uniform but proportional to blade length. The thrust force endured by the blade tip is greater than that of the blade root.
Girder design: The bending deformation caused by the blade's own weight and external thrust is the main load of the blade. In order to improve the bending performance, unidirectional fiber cloth is used in the length direction of the blade, and a shear web is passed in the middle. The plate separates the upper and lower beam caps as much as possible, and the shear web is made of bidirectional fiber cloth and foam (PET) core material laid diagonally to increase the overall rigidity.
Internal beam structure: In order to reduce production costs, some unnecessary materials can be removed from the design. Common blades adopt a hollow design.
Leaf shell: The main function of the leaf shell is to provide an aerodynamic shape. The sandwich structure of the leaf shell increases the rigidity. The sandwich structure is composed of a fiberglass surface layer with a foam (PET) core material or a balsa balsa wood (BALTEK) core material in the middle. The sandwich structure is rigid enough to bear bending loads while preventing debonding. Diagonally distributed fibers in the casing provide the necessary torsional rigidity.
Leaf root design: The leaf root part is usually designed to be round. At the same time, in order to meet maintenance and other needs, the roots of the blades are mostly connected with bolts to facilitate disassembly and assembly. Welded flange connections can be used for metal girders.
Geometric size optimization design: Without changing the blade geometric shape, the blade performance can be changed by adjusting the thickness of the spar cap and the production cost can be reduced. Thinner blades require thicker spar caps, which increases production costs. At the same time, the strength of the web needs to be increased, but because the thickness becomes thinner, the total material consumption does not change significantly. In summary, the optimal design of geometric dimensions requires fan design, load analysis, structureThe best results can be achieved by considering multiple aspects such as design and manufacturing costs.