Implementation of the Three-Phase Induction Machine Model Using Simulink / S-Function

Abstract

In this paper, a generalized induction machine model is implemented using the powerful S-Function (System-Functions) extension capability of the MATLAB/Simulink software package. The model has been formulated by means of the space-phasor notation in which all the three-phase quantities (Voltages, Currents, flux and inductances) are converted to the two-axis d-q notation. The dynamic equations of the induction machine are smartly implemented in a single user defined S-Function block, thus addressing the problem of simulation speed when using ordinary Simulink library blocks. The model is then tested in a direct-on-line startup by applying a three-phase ac voltage signal to the machine. Simulation results are presented for a load torque of 10N.m and 40N.m at t=1s to validate the effectiveness of the proposed model.