Eddy-current formulation for constructing transmission-line models for machine windings

In this paper, an eddy-current formulation is used to determine the transmission-line parameters of a machine winding. It is shown that this formulation covers a broader frequency range than the commonly used low-frequency magnetostatic and high-frequency magnetodynamic approximations. The eddy-current formulation, however, suffers from large computation times and may lead to severe inaccuracies if the finite-element mesh does not resolve the skin depth, a modelling concern that does not exist for the traditional formulations. The three finite-element models are compared according to the accuracy of the resulting transmission-line model applied to the winding of a permanent-magnet synchronous machine.