Optimal flux trajectory analysis of linear induction machine considering thrust transient

The efficiency optimization control (EOC) in steady state optimizes the flux to improve the efficiency of linear induction machine (LIM). However, it is inefficient in dynamic operations, in which the aforementioned flux solution no longer satisfies the change of thrust, thus the efficiency is deteriorated. In this paper, LIM losses including both copper and core losses during thrust transient are analyzed, and a dynamic loss model of LIM is established. A numerical solution to estimate the optimal flux trajectory is derived, and a practical method based on experimental prototype is put forward to minimize the losses as well as to meet the desired thrust response.