Field Oriented Linear Induction Motor Drives: An Electromagnetic Perspective

Linear induction machines (LIM) become more prevalent in a broad range of applications. Field oriented control of this machines, migrated from their rotary counterparts, has been considered as a superior control strategy. This paper reports on secondary effects such as trailing eddy currents, non-sinusoidal magneto-motive force (MMF) in the airgap, and asymmetrical end effects which can significantly undermine the functionality of a direct or indirect field oriented control in this family of machines. Transient finite element (FE) method, incorporating a Maxwell stress tensor method, has been used to address these outstanding issues by quantitative/qualitative measures