Due to the high blade height of wind turbines, the blades are the most vulnerable components to direct lightning strikes. Blades are one of the most expensive components of wind turbines. Most lightning strikes only damage the tip portion of the blades, and a small amount of damage damages the entire blade. There are two main aspects of blade damage caused by lightning strikes: On the one hand, after lightning strikes the blade tip, a large amount of energy is released. The strong lightning current causes the temperature inside the blade tip structure to rise sharply, and the water vaporizes and expands due to heat, thus generating a large mechanical force. , causing the tip structure to explode and damage, and in severe cases, the entire blade will crack. On the other hand, the huge sound waves caused by lightning strikes cause impact damage to the blade structure. Another point worth noting is that lightning strikes usually hit the upper airfoil of the blade.
In view of the destructive characteristics of lightning to equipment, tests have proven that reducing the internal impedance of the structure of the struck object and forming a path to the ground can prevent damage from lightning strikes. According to this characteristic, carbon fiber with good electrical conductivity and light specific gravity is added to the blade upper airfoil composite material, and an air-termination device is installed at the blade tip, connected to the blade flange through a cable, and then passed through the tower through the hub. The ground wire is connected to the ground grid to form a lightning channel. When lightning strikes a blade, the powerful lightning current pours into the ground through the lightning channel, achieving a lightning protection effect without causing damage to the blades and other equipment. In this way, the blades actually become lightning rods, attracting the surrounding lightning and discharging it in advance. Therefore, special attention should be paid to the very small impedance of the lightning channel, the connecting wires must have sufficient conductive cross-section and good conductivity, and the grounding grid must be ensured as much as possible. small impedance value.
On the other hand, lightning energy is very huge and lightning strikes are complicated. Adopting reasonable and appropriate lightning protection measures can only reduce losses. Only with the breakthrough and application of more new technologies can lightning be completely protected and protected. Take advantage of it.
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China's shrinkable wind power blade transport truck has three sections. Three-section pull-out wind turbine blade transportation equipment. The transportation equipment solves the problem that when each pull-out beam of the pull-out wind turbine blade transport vehicle is completely closed, the overall length is occupied due to the bolts, beams and other components at the front end of each pull-out beam. . When the telescopic wind turbine blade transporter is fully closed, each drawing beam completely enters the outer sleeve beam, thus ensuring to the greatest extent that the maximum pulling length can be achieved under the premise that the telescopic wind turbine blade transporter is fully closed and has a certain length. Meet the requirements for wind turbine blade transportation.
Fan vane truck
Fan vane truck is a kind of semi-trailer. Because it is very long, it generally adopts a pull-out structure. The front sections are pulled out toward the The last section of the pull is up to 45 meters long. Because of the wholeThe vehicle is longer and generally uses hydraulic steering. The bridge system has a two-line four-bridge structure and a three-way bridge structure.