Um modelo dq de máquina de indução saturada considerando os harmônicos espaciais de fluxo magnetizante.

Abstract

A new model is being proposed in this work, for representing the three phase induction machine. The model takes into account the spatial fundamental and third harmonic flux distributions that arise from saturation in the main flux path. The saturation in the leakage flux path is neglected. The proposed model combines the model for the machine in a rotating reference frame attached to the air-gap flux, and “magnetic harmonic functions” that describe the nonlinear behaviour coming from saturation. Experimental determination of these functions is also described. The suggested model is predominantly formulated in dq coordinates, as for star and delta connected stator windings, and it can be used for electromagnetic and mechanical transient analysis, despite the kind of source and load employed. Computational simulations are performed, with the help of a recent time domain nonlinear circuit analysis technique. The proposed model is validated by measurements on a 1.5 hp motor. Satisfactory agreement between simulations and measurements is observed. The model is also used in computational simulations of a three-phase self-excited induction generator, for the same machine under consideration.