Simulation of induction machine operation using complex magnetodynamic finite elements

The nonlinear magnetodynamic model implemented in FLUX2D is improved in order to solve the field equations in an induction motor with a highly saturated slot isthmus. The resulting method is an extension to the harmonic solution of nonlinear magnetodynamic problems using the classical finite-element method. This extension applies the nonlinear Newton-Raphson algorithm in the same way as for magnetostatic problems, using the Jacobian matrix presented. The forces and torques obtained by this algorithm are quite identical to those results obtained by a step-by-step simulation. Applied to an industrial four-pole, squirrel cage induction machine, this method gives over the whole range of speed an error less than 5%