Parameter estimation algorithm using spectral analysis for vector controlled induction motor drives

This paper describes an online parameter identification technique based on spectral analysis of machine voltages and currents and injected negative sequence components. The method is based on the analysis of voltages and currents by using the fast Fourier transform algorithm to determine their fundamental components. It is shown that the stator as well as rotor parameters can be determined online while the motor is driving the load with minimum disturbances. The theory is supported by a full scale digital computer simulation of a field oriented induction motor drive including the variation of critical parameters.