Exit end effect reduction of a linear induction motor for the deep-underground GTX

The end effect of a linear induction motor has been well known for several decades, especially for high speed operation. Nevertheless, exit part of the primary is not dealt with relatively compared with the entry part because of its minor effect. However, exit part is one of keys to weaken the dolphin phenomenon which occurs in the high speed operation. In this paper, concept of the virtual primary core is introduced and chamfering of the outlet teeth is proposed to minimize the longitudinal end effect at the exit zone. For this, LIM for the high-speed deep-underground GTX is designed and analyzed by using finite element method. From the results, it is confirmed that the chamfering is effective without losing thrust force.