Improved air gap permeance model to characterise the transient behaviour of electrical machines using magnetic equivalent circuit method

Transient analysis of electrical machines with mixed eccentricity requires dedicated, fast and accurate solvers. This article proposes an improved air gap permeance expression which (a) is physically interpretable and (b) can be easily derived based on the rotor position. This expression is very suitable for inclusion in a solver based on the magnetic equivalent circuit (MEC) method. This allows to for example, calculate the torque and forces when vibrations act on the rotor. The results of the MEC solver agree very well with those obtained with a finite element method (FEM) solver, but are obtained with a fraction of the simulation time of the FEM solver.