Message from editors

RECENT global warming issue is a serious problem. One of the key solutions is to spread Electric Vehicle and/or Hybrid Vehicle. Due to high torque density and efficiency, permanent magnet machines have been used for the traction motors for Electric Vehicle and Hybrid Vehicle. The torque density has been improved for this decade, almost two times torque density has been achieved. Adding that, a new topology of the PM machines which have variable flux topology has been proposed recently, the machine structure has become complex and exciting. On the other hand, magnet-less machines, including induction, switched and synchronous reluctance, and wound-field synchronous machines, can eliminate the use of expensive rare-earth magnets and their design, analysis and control are currently under extensive investigation.