Analytical Analysis of Cage Rotor Induction Motors in Healthy, Defective, and Broken Bars Conditions
Résumé
This paper presents a two-dimensional (2-D) static analytical method in the frequency domain for the calculation of magnetic field distribution, eddy-currents, circuit model parameters and study state performances in multi-phase/-pole cage rotor induction motors with integer and fractional stator winding. The complex model allows the study the healthy, defective and broken bars conditions in these electrical machines. The proposed static analytical model takes into account stator and rotor slotting with tooth-tips. The method is based on the resolution of Poisson’s, Laplace’s and Helmholtz’s equations in stator slots, air-gap and rotor bars regions respectively. The electromagnetic torque is obtained from both the electrical equivalent circuit (EEC) and Maxwell stress tensor that is given by the magnetic field calculation. The analytical results are validated by those issued from time harmonic finite-element method (Fem).