Design considerations for 1 MW class HTS synchronous motor

A 1 MW class superconducting synchronous motor is designed considering several conditions such as superconducting wire length, machine efficiency and size. As the machine is larger and larger, the superconducting machine shows the advantages more and more over the conventional machines. Although the advantages at 1 MW rating are not so great, the design approach to get an appropriate result would be very helpful for larger superconducting synchronous machine design. Major design concerns are focused on reducing expensive Bi-2223 HTS (High Temperature Superconducting) wire which is used for superconducting field coil carrying the rating current around 30 K (-243°C) while the machine efficiency is higher than conventional motors or generators with the same rating. Furthermore, some iron-cored structure is considered to reduce the HTS wire requirement without bad effect on machine performances such as sinusoidal armature voltage waveform, synchronous reactance and so on.