Higher-Order Cosimulation of Field/Circuit Coupled Problems

This paper discusses the weak coupling of nonlinear magnetoquasistatic field models (e.g., of induction motors) to an external electric network model (e.g., of frequency converters). A piece-wise linear inductance (as lumped field model) is not sufficiently accurate if the magnetic field exhibits strong eddy current effects. Here, we propose to represent the field model in the circuit equations by a more complex surrogate model. It is fitted by dynamic iteration (`waveform relaxation´) during the cosimulation procedure. We demonstrate the link between dynamic iterations and the achievable convergence order of the time integrator numerically.