A novel method of transfer-function identification for modeling DM impedance of AC motor

The present paper deals with the development of a detailed identification method based on the frequency response of an induction machine in high frequency, the transfer function are used to represent a mathematical model of AC motor impedance. The proposed model of AC motor impedance is suitable for prediction and analysis the Electromagnetic Interference (EMI) problems in adjustable speed driver (ASD). In this paper, first the magnitude frequency response curve is carried out using the experimental data using Agilent 4294A Impedance Analyzer, and the identification procedure has been improved and it is based on asymptote method applied to the measured magnitude frequency response curve of impedance in Differential-Mode (DM) configuration in order to confirm phase frequency response curve. In the second part, EMC Analysis is discussed in order to understand the path of Differential-Mode currents in adjustable speed driver (ASD).