Structural characteristics and technical difficulties of magnetic levitation wind turbines
Speaking of wind turbines, these two years have been very popular in the industry (especially high-power offshore wind power). So what is the difference between a magnetic levitation wind turbine and it? What are the characteristics of magnetic levitation wind turbines? What structure? What are the technical difficulties? Let's take a look.
1. Structural features and principles
The working principle of the magnetic levitation wind turbine is that the whole or part of the rotating shaft system of the generator is suspended in space through magnetic bearings. The wind drives the blades and the entire rotating shaft system to rotate. The mechanical energy is converted into electrical energy by the generator, and finally the electrical energy generated by the generator is transformed by power electronics. Converter into usable electrical energy.
In addition to the advantages of energy saving and environmental protection, the most important feature of the magnetic levitation wind turbine is the low starting wind speed (1.5-2.5m/s); stable operation, no noise, and long service life; it does not require high space and can be used in urban areas, Used in suburbs and coastal mountainous areas.
According to the relative position of the wind shaft and the ground, magnetic levitation wind turbines are divided into horizontal axis wind turbines and vertical axis wind turbines. Due to the many advantages of vertical axis wind turbines, it has been extensively developed in recent years.
2. The key technology of magnetic levitation wind turbine research
Wind turbine blade technology
Including the shape and structure design (the common shapes of wind turbine blades are arc, straight, wing and torsion) and material selection (aluminum alloy chord blades, steel blades, glass fiber reinforced plastic blades, etc.). At present, glass fiber reinforced plastic composite materials are widely used).
Magnetic levitation support technology
At present, the bearings used in the support technology of magnetic levitation wind turbines are mainly divided into mechanical bearings, active magnetic bearings, hybrid magnetic bearings and passive magnetic bearings. The purpose of choosing different support methods is to reduce the friction between the bearings, minimize the mass, and improve the efficiency of wind energy conversion.
Energy storage technology
In order to reduce the impact of the intermittency and volatility of wind power on the stability of the power grid, my country has built large energy storage stations in areas where wind power is concentrated. Using the two-way adjustment function of the energy storage station, the remaining power of the grid is absorbed to the trough, the wind power is converted into high-quality electric energy for storage, and the abandonment of wind power is reduced. Thereby improving the safety and stability of grid operation and the utilization rate of wind generators, reducing wind power abandonment, and increasing the proportion of clean energy power generation.
At present, the main energy storage methods are physical energy storage, electrochemical energy storage and electromagnetic energy storage. Physical energy storage is divided into pumped water energy storage, compressed air energy storage and flywheel energy storage. Electrochemical energy storage equipment includes battery energy storage, fuel cell energy storage, lithium ion batteries, etc.; electromagnetic energy storage is mainly superconducting magnetic energy storage.
In addition, it also includes generator technology (application of permanent magnet synchronous motor), control technology (wind turbine control technology, magnetic levitation control technology) and so on.