A novel control strategy of linear induction motor drives based on dynamic maximum force production

Linear induction motor (LIM) drives have been investigated vastly for the past several decades. Attractive features, such as simple structure and easy maintenance, have made this family of machines utilized broadly in military, transportation, and aerospace, to name a few. Up to nowadays, vector control is a dominant control strategy for LIM based on the assumption that this family of machines portray inherent similarities with their rotary counterparts. However, due to existence of end effects and magnetic asymmetry effects, conventional vector control can not provide its expected functionality for LIM. Therefore, a novel control strategy, dynamic maximum force control, is invented and presented in this paper. Compared with conventional vector control, the excitation frequencies are calculated through field reconstruction (FR) in the proposed control method. In addition, the amplitude of phase current is regulated indirectly through controlling the square of current amplitude. As a result, at any instant, maximum force production is guaranteed. The dynamic maximum force control has been validated by simulation study.