Coupling dynamic electromagnetic finite element models to circuit simulators by using model order reduction

Two model reduction methods, proper orthogonal decomposition (POD) and discrete empirical interpolation method (DEIM) are applied to a finite-element model of a one-phase transformer. The resulting reduced order model is strongly coupled with a system simulator and the performance, feasibility and accuracy of the resulting system is studied. The results show that the workload of evaluating the finite element model drops drastically as the amount of degrees of freedom reduces by 99% and the amount of involved elements reduces by 65%. The accuracy of the results is feasible. The time to calculate a single timestep reduces on average 75%. The full simulation time drops on average by 45%. In this case the performance of the naive coupling is bad because it introduces two nested nonlinear solvers. This reduces the total speed up of the simulation.