Numerical simulation of transient electro-quasistatic fields using advanced subspace projection techniques

The transient simulation of electro-quasistatic fields requires a formulation that takes both dielectric effects as well as nonlinear conductive effects into account. The successive solution of large linear systems of equations with similar or even identical system matrices has to be performed repeatedly if this formulation is discretized by the Finite Element method and an Implicit-Runge-Kutta method, respectively. The solution processes can be accelerated by using subspace recycling techniques and subspace projection extrapolation techniques. Numerical results for three-dimensional high-voltage applications are presented and the efficiency of these techniques is shown.