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
- 2019
4117.
Hartikainen, Markus; Miettinen, Kaisa; Klamroth, Kathrin
Interactive nonconvex Pareto navigator for multiobjective optimization
European Journal of Operational Research, 275 (1) :238-251
20194116.
Pulch, Roland; Putek, Piotr; De Gersem, Herbert; Gillon, Renaud
Inverse modeling: Glue-Package-Die problem
In ter Maten, E. Jan W. and Brachtendorf, Hans-Georg and Pulch, Roland and Schoenmaker, Wim and De Gersem, Herbert, Editor aus Mathematics in Industry
Seite 279–289
Herausgeber: Springer Cham
2019
279–2894115.
Ehrhardt, Matthias; Vázquez, Carlos
Jump-diffusion models with two stochastic factors for pricing swing options in electricity markets with partial-integro differential equations
Applied Numerical Mathematics, 139 :77–92
2019
Herausgeber: North-Holland4114.
Ehrhardt, Matthias; Vázquez, Carlos
Jump-diffusion models with two stochastic factors for pricing swing options in electricity markets with partial-integro differential equations
Applied Numerical Mathematics, 139 :77--92
2019
Herausgeber: North-Holland4113.
Ehrhardt, Matthias; Vázquez, Carlos
Jump-diffusion models with two stochastic factors for pricing swing options in electricity markets with partial-integro differential equations
Applied Numerical Mathematics, 139 :77–92
2019
Herausgeber: North-Holland4112.
Kleefeldt, Simon; Bohrmann-Linde, Claudia
Keep Track of The Heat
20194111.
Griebel, M.; Rieger, C.; Zaspel, Peter
Kernel-based stochastic collocation for the random two-phase Navier-Stokes equations
IJUQ, 9 (5)
20194110.
Jensen, Per
Linear and bent triatomic molecules are not qualitatively different!
Canadian Journal of Physics :1-6
2019
Herausgeber: NRC Research Press4109.
Bolten, Matthias; Claus, L.
Local Fourier Analysis of multigrid methods for the Stokes problem
PAMM, 19 :e201900394
20194108.
Bolten, M.; Claus, L.
Local Fourier Analysis of multigrid methods for the Stokes problem
PAMM, 19 :e201900394
20194107.
Bolten, M.; Claus, L.
Local Fourier Analysis of multigrid methods for the Stokes problem
PAMM, 19 :e201900394
20194106.
Glück, Jochen; Wolff, Manfred P. H.
Long-term analysis of positive operator semigroups via asymptotic domination
Positivity, 23 (5) :1113--1146
20194105.
Ehrhardt, Matthias; Gašper, Ján; Kilianová, Sona
Mathematical Modeling of an SIR-based infectious disease model with vaccination and waning immunity
20194104.
Gerlach, Moritz; Glück, Jochen
Mean ergodicity vs weak almost periodicity
Studia Math., 248 (1) :45--56
20194103.
[german] Yurdanur, Yasemin; Tausch, Michael W.
Metamorphoses of an Experiment - From Hightech UV Immersion Lamp Reactor to Low-Cost TicTac\(^{®}\)-Cell
{CHEMKON}, 26 (3) :125--129
2019
Herausgeber: Wiley4102.
Schulze, Britta; Stiglmayr, Michael; Klamroth, Kathrin
Multi-Objective Unconstrained Combinatorial Optimization: A Polynomial Bound on the Number of Extreme Supported Solutions
Journal of Global Optimization, 74 (3) :495–522
20194101.
Friedhoff, S.; Hahne, J.; Schöps, S.
Multigrid-reduction-in-time for Eddy Current problems
PAMM, 19 (1) :e201900262
20194100.
Friedhoff, S.; Hahne, J.; Schöps, S.
Multigrid-reduction-in-time for Eddy Current problems
PAMM, 19 (1) :e201900262
20194099.
Friedhoff, S.; Hahne, J.; Schöps, S.
Multigrid-reduction-in-time for Eddy Current problems
PAMM, 19 (1) :e201900262
20194098.
Hachtel, Christoph; Bartel, Andreas; Günther, Michael; Sandu, Adrian
Multirate implicit Euler schemes for a class of differential{\textendash}algebraic equations of index-1
JCAM :112499
September 2019
Herausgeber: Elsevier {BV}4097.
Bartel, Andreas; Günther, Michael
Multirate Schemes
Novel Mathematics Inspired by Industrial Challenges :5
20194096.
Nanoelectronic Coupled Problems Solutions
In ter Maten, E. J. W. and Brachtendorf, H.-G. and Pulch, R. and Schoenmaker, W. and De Gersem, H., Editor, Band 29 aus Mathematics in Industry
Herausgeber: Springer
20194095.
Tischendorf, Caren; Maten, E. Jan W.; Schoenmaker, Wim
Nanoelectronic coupled problems solutions – Highlights from the nanoCOPS project
In ter Maten, E. Jan W. and Brachtendorf, Hans-Georg and Pulch, Roland and Schoenmaker, Wim and De Gersem, Herbert, Editor aus Mathematics in Industry
Seite 1–21
Herausgeber: Springer Cham
2019
1–214094.
Demirkan, Reşat-Anıl
Neuartige Emulgatoren und deren Eignung für Rapsöl und Rapsölmethylester Emulsionen
20194093.
Schöps, Sebastian; Duque Guerra, David J; De Gersem, Herbert; Bartel, Andreas; Günther, Michael; Pulch, Roland
Non-Intrusive Methods for the Cosimulation of Coupled Problems
Nanoelectronic Coupled Problems Solutions :131--159
2019
Herausgeber: Springer International Publishing