1. Shell Global Solution International B.V., Rijswijk, The Netherlands
2. Power Systems Engineering Center, National Renewable Energy Laboratory, Golden, CO, USA
3. University of Strathclyde, Glasgow, U.K.
4. Siemens Gamesa, Gentofte, Denmark
5. Orsted, Gentofte, Denmark
6. Delft University of Technology, Delft, The Netherlands