Analysis of Linear Induction Machines with Different Number of Poles highlighting the Different Indicators for End Effects Estmation

This paper presents an analysis of how end effects in Linear Induction Machines (LIMs) vary with the number of poles in any particular LIM. Simulation of three LIMs with different number of poles has been carried out using Finite Element Method (FEM). It has been shown that the flux distortion caused by end effects and the peak-peak ripple that appears in propulsive force, both of them come down with rise in number of poles. Based on the force speed characteristics derived from FEM simulation, the equivalent circuit parameters have been calculated for all the three LIMs. Using the equivalent circuit, end effects have been estimated by comparing the performance of the LIM in presence and in absence of end effects. It has been shown that the loss of flux, the loss of propulsive force and the loss of magnetizing inductance, all of them decrease with rise in LIM’s number of poles. These losses behave in a similar manner as the flux distortion and the force ripple.