Assessment of flux observer performance for induction motor drive

This work presents a methodology of flux observers developing for induction machine through the analysis of structures performances, the study of a gain design criteria and the practical evaluation with the implementation of the direct field orientation control and observers. It shows the analysis of some known observer structures using the frequency response function (FRF) and the computation costs. A gain design criteria, based on robust control theory, was studied and applied to each observer. The observer performance, with this criteria, is verified again using its FRF. Finally, the results are obtained in a laboratory from an AC drive system prototype for these topologies