The EcoSwing consortium has developed a full-size superconducting generator for a 3.6 megawatt wind turbine and tested it at a wind power plant in Denmark.
Member of the team that has developed the new wind rotor, Anne Bergen, from the University of Twente, the Netherlands, said: "The size of the wind turbine has grown significantly in recent decades. However, current technology has trouble staying up to date with the trend towards increasing unit power levels. "
"Direct-drive (DD) generators based on permanent magnets (PM) offer a solution in state-of-the-art multi-megawatt generators, but the viability of PM-DD turbines of more than 10 megawatts requires a significant reduction in weight. The machines Pseuodmagnetic direct drive (PDD), which integrate magnetic gear and generation functions, are a possible solution to this, but they can be expensive and very complex to produce. "
To meet this challenge, the team employed high temperature superconducting generators of copper oxide and rare earth barium (ReBCO).
These require a smaller amount of rare earth materials than PM machines, resulting in a lower cost. Superconductors can also carry high current densities, resulting in more power-dense coils and a lower weight.
Bergen said: "The generator field test was extremely successful. When the generator was installed in Thyborn, the turbine reached its target power range, including more than 650 hours of operation. This shows the compatibility of superconducting generator technology with all elements of an operating environment such as variable speeds, network failures, electromagnetic harmonics and vibrations. "
The project achieved several important advances. He demonstrated that the production of HTS coils is not limited to specialized laboratories and constitutes a successful transfer of technology from science to industry. The HTS rotor was also assembled in an industrial environment, showing that superconducting components can be implemented in a 'standard' manufacturing environment.
"Now that the concept has been tested, we hope to see superconductor generator technology begin to be widely applied in wind turbines," he added.