Juha Pyrhönen, Electrical Engineering, School of Energy Systems, Lappeenranta University of Technology, Finland Juha Pyrhönen is a Professor in the Department of Electrical Engineering at the Lappeenranta University of Technology, Finland, He is engaged in the research and development of electrical motors and drives. He is especially active in the fields of permanent magnet synchronous machines and drives and in solid-rotor high-speed induction machines and drives. He has been an innovator in many industrial development projects and has produced numerous publications and patents in the field of electrical engineering. Valéria Hrabovcová, Faculty of Electrical Engineering, University of Žilina, Slovakia Valéria Hrabovcová is a Professor of Electrical Machines in the Department of Power Electrical Systems, Faculty of Electrical Engineering, at the University of Žilina, Slovakia. Her professional and research interests cover all kinds of electrical machines, including electronically commutated electrical machines. She has worked on many research and development projects and has written numerous scientific publications in the field of electrical engineering. R Scott Semken, Mechanical Engineering, School of Energy Systems, Lappeenranta University of Technology, Finland R Scott Semken is a Doctor of Science in Technology working in the School of Energy Systems at the Lappeenranta University of Technology, Finland. He focuses primarily on the mechanical aspects of motor and generator technologies, in particular, permanent magnet synchronous and solid-rotor high-speed induction machines and drives. The unique problems associated with very high power direct-drive wind turbine drivetrains have been an area of recent interest leading to in depth investigations of stator winding cooling and manufacturing approaches and large diameter permanent magnet rotor structures.