By Kari Williamson

Keith Longtin, Wind Technology Leader, GE Global Research, says: “Applying more than 30+ years of experience with superconducting magnets for MRI systems in healthcare, we’re developing an innovative new generator technology that will deliver more power while at the same time helping to reduce the cost of wind power.

“For MRI systems, we’re applying superconducting magnets to make lower cost systems with higher image quality,” Longtin adds. “For wind turbines, we want to apply them to generate more wind power at a lower cost of electricity. The applications are different, but the basic technology is the same.”

The application of superconducting technology could enable significant improvements to the wind turbine generator and make the elimination of the gearbox more economical. The keys are reducing the size and weight of the generator, while reducing speed and increasing torque, Longtin explains.

Using superconducting technology reduces weight by virtue of the high magnetic fields that can be created by the superconducting field winding and the fact that the heavy iron in the superconducting generator can be reduced.

GE's superconducting wind turbine machine design will employ a novel architecture and proven cryogenic cooling technology, which could result in improved reliability of the complete machine.

GE's proposed superconducting wind turbine generator aims to have twice the torque density of competing technologies and would reduce the dependence on the rare earth materials prevalent in all permanent magnet machines used in the wind power industyr.

In addition to the superconducting wind turbine generator, GE is also looking at:

• Incorporating lighter composite materials to enable longer wind turbine blades;
• Delivering more advanced controls, sensors and condition monitoring algorithms to further reduce operating costs; and
• Developing an array of grid integration technologies to integrate larger amounts of wind power into the grid.

Two-phase project

The 10-15 MW wind turbine generator project will have two phases. Phase I will focus on developing a conceptual design and evaluating the economic, environmental, and commercial factors associated with it. Phase II will explore the potential commercialisation of the technology.

Oak Ridge National Lab (ORNL) will be a key partner with GE on the wind turbine generator project.