Since the grid-connected wind turbines start and stop more frequently, the impeller's own moment of inertia is very large. The impeller speed of large and medium-sized wind turbines is generally designed to be 20-40 rpm. The larger the unit capacity, the longer the impeller diameter and the relative speed. The lower the speed, in order to meet the working conditions of the asynchronous two-speed motor, the gearbox growth speed needs to be installed between the impeller and the generator. Due to the size limitations of the nacelle, the mechanical transmission systems of large wind turbines are generally arranged along the axis of the nacelle. The gearbox has also been changed from the previous multi-stage spur or helical gearbox to more compact planetary gearboxes. As the transmission torque of the gearbox used by large wind turbines increases, the structure is more compact and complicated, and the requirements for maintenance and repair personnel of wind turbines are also constantly increasing.
1. Daily maintenance and regular maintenance
1) Daily maintenance
The daily maintenance contents of the wind turbine gearbox mainly include: equipment appearance inspection, lubricating oil level inspection, electrical wiring inspection, etc.
The specific tasks include: cleaning the surface of the gear box when the operator is on board, checking whether the tank and the lubrication pipeline are leaking, whether the external lubrication line is loose or not, because the wind turbine vibration is large, if Poor fixing of the externally applied pipe will result in damage to the pipe joint seal or even breakage of the pipe. In addition, pay attention to the looseness and leakage of the oil drain valve at the bottom of the tank to avoid a large amount of leakage of the gear oil caused by the loosening and leakage of the oil drain valve.
Check the oil level and oil color from the oil scale or oil level window. If the oil level is low, it should be replenished in time. If it is found that the oil color is obviously dark and black, the oil quality inspection should be considered and the operation monitoring of the unit should be strengthened. In case of filter clogging alarm, it should be checked and treated in time. When replacing the filter element, the inside of the filter should be thoroughly cleaned. It is best to remove the filter assembly in the workshop for cleaning and inspection. When installing the filter housing, pay attention to the positive thread and apply even force to avoid damage to the thread and seal.
Check the gear oil level, temperature, pressure, differential pressure, bearing temperature and other sensors and heaters, heat sink wiring is normal, the wire is worn. In the daily inspection, you should also pay attention to the noise of the unit, and find the hidden troubles in time.
2) Regular maintenance
Regular maintenance and repair of wind turbines mainly includes: torque check of gear box connecting bolts, gear meshing and tooth surface wear inspection, sensor function test, lubrication and heat dissipation system function check, regular replacement of gear oil filter, oil sample collection, etc. When conditions permit, the industrial testing equipment can be used to detect and analyze the vibration and noise of the gearbox operating state, in order to more comprehensively grasp the working state of the gearbox.
According to the wind turbine operation and maintenance manual, different manufacturers have different sampling cycles for gear oil. It is generally required to be sampled once a year, or the gear oil can be sampled once every two years. For the gearbox with abnormal operating conditions, collect the oil sample as needed. Gear oils are typically used for three to four years. Since the operating indexes of the gearbox, such as operating temperature, annual operating hours and peak output, are not the same, the gears are replaced in the same time as the gear oil replacement conditions. It is not guaranteed to operate the gearbox economically and safely under different operating conditions. . This requires the operating personnel to pay attention to the various operating data of the collection unit, compare and analyze the various parameters of the oil test results, and find out the oil replacement cycle that is more in line with the characteristics of their own electric field operation.https://www.delinggearbox.com/