Wind power, an infinite source of energy
People have been making use of wind power for hundreds of years. Whilst in earlier times, windmills were used for milling grains or as sawmills, nowadays state-of-the-art wind turbines harvest electricity from the power of the wind. Wind power, as a renewable energy, is acquiring a central role in the energy mix of more and more countries. Since wind is available all over the world, wind power is a mainstay of the global energy supply.
Wind energy is experiencing a global boom
The demand for wind energy is constantly growing. According to data from the World Wind Energy Association (WWEA), electricity is already being generated from wind power in 100 countries. Energy generation from wind power is being expanded dramatically in Western Europe, Asia and North America, in particular, as well as in offshore regions, in order to cover the rising energy demands of countries in these regions. The projections are looking good for the long-term: the WWEA believes there could be a ten-fold increase in global production of electricity from wind in the next 20 years.
SEMIKRON technology in nearly half of all wind turbines
In the early 1990s, SEMIKRON developed the first power modules for use in wind turbines. Today the company is a market leader in this field of IGBT modules. Almost every second turbine in the world is fitted with SEMIKRON power modules, which operate at several key points: the main inverter (output range of around 2 MW to 8 MW) and the auxiliary inverters (5 kW to 50 kW), which are responsible for aligning the rotor blades (pitch drive) and the nacelle (azimuth drive).
Power semiconductors ensure consistent energy transmission
Whilst the intensity of power and thus of light produced by a bicycle dynamo varies depending on speed, in wind turbines power semiconductors are used to ensure that the energy transmission remains consistent in spite of fluctuating wind and generator speeds. Varying wind speeds lead to fluctuating voltages and frequencies. The power electronics control and regulate the generated electricity in such a way that it can always be fed to the public power grid with the correct line frequency and quality.
Focus on reliability and compactness
In wind power plants, the reliability of the power electronics has top priority – next to high energy efficiency – as downtimes mean monetary losses for the operator. In a selection of power modules, SEMIKRON has replaced traditional soldered connections with pressure contacts or sintered connections, making the modules very robust and durable. Size is another important feature, as the converters usually have to be installed in the narrow nacelles or in the base of the tower. Future technology from SEMIKRON will make it possible to double the power density in the IGBT module, enabling a significant reduction in the volume of the converter.