Normal force in single-sided linear induction motors

It is shown that the normal force in a single-sided linear induction motor can be appreciable, and that it is highly dependent on the speed and terminal conditions. Two simple theories are presented, and these are compared with experimental results. Tests were performed on both static and dynamic machines showing the variation of normal force with frequency and speed, and the effects of pole changing and plugging. It is concluded that the normal force and the possible changes that can occur in its magnitude and direction are highly significant design factors.