Novel Simulation of Cage Windings Based on Mesh Circuit Model

Representing the cage winding of a polyphase induction motor as a set of mesh circuits results in the rotor being faithfully modelled by a simple symmetric matrix. The application of a new transform reduces the model to its two-axis equivalent with novel expressions for impedance, which avoid many of the complications of other methods of cage winding simulation. The derived impedance expressions are rigourously applicable to machines which are unbalanced to the extent of having non-integral numbers of rotor bars per pole-pair. No assumptions are required about the magnitudes of rotor currents and all harmonics can be included.