Electromagnetic design of a megawatt high efficiency high speed solid rotor induction motor

Compared with other types of motors, solid rotor induction motor has the simplest and most robust construction. This good performance makes the solid rotor induction motors widely used in numerous high speed and high output applications. In this paper, the electromagnetic design process of an 18 MW, 12000 rpm solid rotor induction motor is discussed. In order to improve the rotor electromagnetic properties, the rotor of the developed induction motor is axially slitted with copper end rings. Then the characteristics of the magnetic field distribution, airgap flux density and motor performance are analyzed by using two-dimensional time-stepping finite element method (2D T-S FEM). It is found that the developed motor achieves good performance. Finally, the loss distribution characteristics of the developed motors are studied; and the iron loss caused by the fundamental and harmonic field is also analyzed.