Computational Magnetics
Many electro-technical devices such as e.g. printed circuit boards, electrical drives and antenna systems can be simulated on the basis of electrical circuits. However, the increasing frequencies and the decreasing size force designers to account for wave propagation effects, eddy-current effects, ferromagnetic saturation and hysteresis. For wave propagation effects and eddy-current effects, the results of stand-alone field simulation can be represented by an order-reduced equivalent model, which is then inserted in the overall circuit model. The representation of field-dependent nonlinearities and hysteresis effects, however, is not straightforward.

2D Simulation of a Transformer
The coupled field and circuit simulation becomes troublesome when a large number of time steps is required. This occurs when e.g. simulating an electrical drive where the machine requires 10 periods of 50 Hz to reach nominal speed whereas the switching of the Insulated Gate Bipolar Transistors in the frequency converter switches at 20 kHz, necessitating a time steps in the order of a microsecond to be used in the simulation. Since the field model consists typically of a few million degrees of freedom, all those unknowns have to be solved in every time step. Fortunately, the relevant time constants in electrical-energy converter are in the range 50 Hz. Hence the field model does not have to be time-stepped at the same rate as the circuit model, in which fast switches are present. The use of adaptive multirate time-integration schemes can reduce the numerical complexity of the problem substantially.
Research Questions
- Efficiency of the time-integration for field devices in pulsed circuits (multirate, dynamic iteration)
- DAE-index of the coupled system
- Existence and Uniqueness of the solution
Cooperation
- Herbert De Gersem, Katholieke Universiteit Leuven
- Markus Clemens, Bergische Universität Wuppertal
- Sascha Baumanns, Universität zu Köln
Former and ongoing projects
Publications
- 2016
3292.
Wandelt, Michèle; Knechtli, Francesco; Günther, Michael
The Wilson flow and the finite temperature phase transition
Journal of High Energy Physics, 2016 (10) :1--13
2016
Herausgeber: Springer Berlin Heidelberg3291.
Ehrhardt, Matthias
Transparent boundary conditions for iterative high-order parabolic equations
Journal of Computational Physics, 313 :144--158
2016
Herausgeber: Academic Press3290.
Ehrhardt, Matthias
Transparent boundary conditions for iterative high-order parabolic equations
Journal of Computational Physics, 313 :144–158
2016
Herausgeber: Academic Press3289.
Ehrhardt, Matthias
Transparent boundary conditions for iterative high-order parabolic equations
Journal of Computational Physics, 313 :144–158
2016
Herausgeber: Academic Press3288.
Tausch, Michael W.; Flint, Alfred
Trendbericht Chemiedidaktik: Experimentell-konzeptionelle Forschung
Nachrichten aus der Chemie, 64 (3) :359--360
2016
Herausgeber: Wiley3287.
Putek, Piotr; Meuris, Peter; Pulch, Roland; Maten, E. Jan W.; Schoenmaker, Wim; Günther, Michael
Uncertainty quantification for robust topology optimization of power transistor devices
IEEE Transactions on Magnetics, 52 (3) :1–4
2016
Herausgeber: IEEE3286.
Putek, Piotr; Meuris, Peter; Pulch, Roland; Maten, E. Jan W.; Schoenmaker, Wim; Günther, Michael
Uncertainty quantification for robust topology optimization of power transistor devices
IEEE Transactions on Magnetics, 52 (3) :1–4
2016
Herausgeber: IEEE3285.
Schmiedt, Hanno; Jensen, Per; Schlemmer, Stephan
Unifying the rotational and permutation symmetry of nuclear spin states: Schur-Weyl duality in molecular physics
Journal of Chemical Physics, 145 (7) :074301
20163284.
Schmiedt, Hanno; Jensen, Per; Schlemmer, Stephan
Unifying the rotational and permutation symmetry of nuclear spin states: Schur-Weyl duality in molecular physics
Journal of Chemical Physics, 145 (7) :074301
20163283.
Schmiedt, Hanno; Jensen, Per; Schlemmer, Stephan
Unifying the rotational and permutation symmetry of nuclear spin states: Schur-Weyl duality in molecular physics
Journal of Chemical Physics, 145 (7) :074301
20163282.
Nehring, Alexandra
Untersuchung der Pyrolyse von verschiedenen Lignin-Ablaugen
20163281.
Klotz, Pascal
Untersuchung von halogenorganischer Sekundärbelastung in Folge von Peroxodisulfat basierter AOP-Behandlung
20163280.
Gann, Stan
Untersuchungen von Temperaturverhalten der NIR-Spektren an ausgewählten Substanzen
20163279.
Laun, Sabrina
Untersuchungen zur Nutzbarmachung von Ligninabbauprodukten als nachwachsende Rohstoffe
20163278.
Sayed, S. El; Bolten, Matthias; Pleiter, D.
Using file system counters in modelling parallel I/O architectures
ACM SIGOPS OSR, 50 (2) :37-46
20163277.
Sayed, S. El; Bolten, M.; Pleiter, D.
Using file system counters in modelling parallel I/O architectures
ACM SIGOPS OSR, 50 (2) :37-46
20163276.
Sayed, S. El; Bolten, M.; Pleiter, D.
Using file system counters in modelling parallel I/O architectures
ACM SIGOPS OSR, 50 (2) :37--46
20163275.
Jacob, Birgit; Langer, Matthias; Trunk, Carsten
Variational principles for self-adjoint operator functions arising from second-order systems
Oper. Matrices, 10 (3) :501--531
20163274.
Farkas, B{\'a}lint; Wegner, Sven-Ake
Variations on {B}arbalat's lemma
Amer. Math. Monthly, 123 (8) :825--830
20163273.
Farkas, Bálint; Wegner, Sven-Ake
Variations on Barbalat's lemma
Amer. Math. Monthly, 123 (8) :825--830
20163272.
George, Christian; Herrmann, Hartmut; Kleffmann, Jörg
Verbessert Photokatalyse die Luftqualit{ä}t?
Nachrichten aus der Chemie, 64 (6) :613-616
2016
Herausgeber: John Wiley \& Sons, Ltd3271.
George, Christian; Herrmann, Hartmut; Kleffmann, Jörg
Verbessert Photokatalyse die Luftqualit{ä}t?
Nachrichten aus der Chemie, 64 (6) :613-616
2016
Herausgeber: John Wiley \& Sons, Ltd3270.
George, Christian; Herrmann, Hartmut; Kleffmann, Jörg
Verbessert Photokatalyse die Luftqualität?
Nachrichten aus der Chemie, 64 (6) :613-616
2016
Herausgeber: John Wiley & Sons, Ltd3269.
Bredenkamp, Angela; Wegener, Michael; Hummel, Sara; Häring, Andreas P.
Versatile process for the stereodiverse construction of 1,3-polyols: iterative chain elongation with chiral building blocks
Chemical Communications, 52 (9) :1875–1878
2016
ISSN: 1364-548X3268.
Petrov, P.; Makarov, D. V.; Ehrhardt, M.
Wide-angle parabolic approximations for the nonlinear {Helmholtz} equation in the {Kerr} media
EPL, 116
2016