2D nonlinear finite element modelling of electromagnetic retarders using time-stepping algorithms, and the Petrov-Galerkin method with homogenization techniques

This paper describes a method for finite element modelling of transient 2D eddy currents in the nonlinear moving conductor of an electromagnetic retarder. The magnetic vector potential A formulation is used, with a general single-step time-marching algorithm, and the fixed and moving coordinate systems are compared. A homogenization technique, inspired by the lamination modelling, is used to make the geometry of a moving region invariant along the speed direction, in order to use a more direct method to compute the steady state eddy currents in the whole rotor. Results are compared to measurements.