Dynamic model of induction machine with faulty rotor in field reference frame

Abstract

This paper presents a control model of squirrel cage induction machine with broken rotor bars. The basis for model's equations is the fact that this type of faults inevitably alters the rotor parameters. Both the resistance and inductance take a sinusoidal shape, being a function of rotor angle, almost regardless of the configuration of fault. Differing from previous work, in this paper a model has been developed in rotor field coordinates, being this the preferable reference frame for machine control and thus easier for control engineers to grasp, especially in closed-looped systems. The approach has been tested on laboratory models of two different induction machines connected to the grid with completely different severities of faults. The results show a very good agreement between measurements and simulations.