Wind Generator Magnets and Their Role in Wind Turbine Generators

Wind is one of the fastest growing clean energy sources on earth, with the world's largest wind farms producing over a billion megawatts of electricity each year. Magnets play a key role in the design of wind turbine generators, allowing them to be efficient, reliable and inexpensive to operate.

Wind turbines consist of large fan blades that are turned by high winds to produce power. They then spin a generator to convert the motion into electricity. This power is then distributed to the grid.

Several wind turbine manufacturers use permanent magnet generators (PMGs) in their products to lower costs, increase reliability and reduce maintenance intervals. PMGs eliminate wearing parts, which reduces the number of components and increases the life span of the turbine.

The wind industry prefers PMGs to other technologies because they offer low failure rates and high reliability without wear and tear. Additionally, PMGs reduce the size and weight of the generator to reduce manufacturing cost and increase the efficiency of the wind turbine.

Magnetic mounting solutions can significantly reduce construction time and costs, protecting the tower from metal fatigue and corrosion. They also eliminate the need for drilling holes through the tower wall, which can lead to damage and compromise the integrity of the tower.

These mounting systems can also help wind farm operators avoid costly repairs to the tower as well as other equipment, such as the rotors, gearboxes and cables. They can also prevent the rotors from becoming overheated and losing their ability to generate power, which can lead to premature breakdowns.

Magnets used in wind turbines are often rare earth elements, which require special treatment to prevent contamination and ensure their long-term safety. There are two types of rare earth elements that are particularly suited for turbines: neodymium iron boron (NdFeB) and samarium cobalt (SmCo).

Neodymium magnets are a common choice in turbines due to their high strength, durability, corrosion resistance and ease of manufacturing. They are also the strongest and most widely available.

Samarium cobalt is less expensive than neodymium and has a wider temperature range, which can help it maintain its magnetism even in a hot environment. However, samarium cobalt magnets are not as strong as NdFeB, so they can lose their magnetic properties if overheated.

The cost of rare earth elements will rise in the near future as global demand for them grows, with many observers predicting that they will double in price by 2025. This will be driven largely by structural reforms in China that are restricting production, as well as a rapid uptake of electric vehicles and the wind sector.