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
3267.
Wide-angle parabolic approximations for the nonlinear Helmholtz equation in the Kerr media
Europhysics Letters, 116 (2) :24004
2016
Herausgeber: IOP Publishing3266.
Makarov, D. V.; Ehrhardt, Matthias
Wide-angle parabolic approximations for the nonlinear Helmholtz equation in the Kerr media
Europhysics Letters, 116 (2) :24004
2016
Herausgeber: IOP Publishing3265.
Makarov, D. V.; Ehrhardt, Matthias
Wide-angle parabolic approximations for the nonlinear Helmholtz equation in the Kerr media
Europhysics Letters, 116 (2) :24004
2016
Herausgeber: IOP Publishing3264.
Göstl, Robert; Sijbesma, R. P.
π-extended anthracenes as sensitive probes for mechanical stress
Chemical Science, 7 (1) :370--375
Januar 2016
ISSN: 2041-6539- 2015
3263.
Göstl, Robert; Sijbesma, Rint. P.
Autonomous repair of polymer networks by stress-induced catalyst activation
Seite 3--9
Herausgeber: Delft University Press
1 Edition
November 2015
3--9ISBN: 978-1-61499-514-2 978-1-61499-513-5
3262.
Fredersdorf, Maic; Göstl, Robert; Kolmer, Andreas; Schmidts, Volker; Monecke, Peter; Hecht, Stefan; Thiele, Christina M.
Exploring the Conformational Space of Bridge-Substituted Dithienylcyclopentenes
Chemistry – A European Journal, 21 (41) :14545--14554
Oktober 2015
ISSN: 1521-37653261.
Göstl, Robert; Hecht, Stefan
Photoreversible Prodrugs and Protags: Switching the Release of Maleimides by Using Light under Physiological Conditions
Chemistry – A European Journal, 21 (11) :4422--4427
März 2015
ISSN: 1521-37653260.
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
März 2015
Herausgeber: IEEE3259.
Tausch, Michael W.; Meuter, Nico
''Photonen und Moleküle - Photolumineszenz und Photochromie'', Begleitheft zur gleichnamigen Interaktionsbox
Herausgeber: Hedinger, Stuttgart
20153258.
Tausch, Michael W.
''Photoprozesse als Kernthema'', Chemie und Energie in Schülerlaboren
TU Braunschweig
20153257.
Jacob, Birgit; Morris, Kirsten; Zwart, Hans
{C_0}-semigroups for hyperbolic partial differential equations on a one-dimensional spatial domain
J. Evol. Equ., 15 (2) :493--502
20153256.
Jacob, Birgit; Morris, Kirsten; Zwart, Hans
C_0-semigroups for hyperbolic partial differential equations on a one-dimensional spatial domain
J. Evol. Equ., 15 (2) :493--502
20153255.
Friedhoff, S.; MacLachlan, S.
A generalized predictive analysis tool for multigrid methods
Numer. Linear Algebra Appl., 22 (4) :618-647
20153254.
Friedhoff, S.; MacLachlan, S.
A generalized predictive analysis tool for multigrid methods
Numer. Linear Algebra Appl., 22 (4) :618-647
20153253.
Friedhoff, S.; MacLachlan, S.
A generalized predictive analysis tool for multigrid methods
Numer. Linear Algebra Appl., 22 (4) :618-647
20153252.
Sandu, Adrian; Günther, Michael
A generalized-structure approach to additive Runge--Kutta methods
SIAM Journal on Numerical Analysis, 53 (1) :17--42
2015
Herausgeber: Society for Industrial and Applied Mathematics3251.
Sandu, Adrian; Günther, Michael
A generalized-structure approach to dditive Runge-Kutta methods
SIAM Journal on Numerical Analysis, 53 (1) :17–42
2015
Herausgeber: Society for Industrial and Applied Mathematics3250.
Sandu, Adrian; Günther, Michael
A generalized-structure approach to dditive Runge-Kutta methods
SIAM Journal on Numerical Analysis, 53 (1) :17–42
2015
Herausgeber: Society for Industrial and Applied Mathematics3249.
Dächert, Kerstin; Klamroth, Kathrin
A linear bound on the number of scalarizations needed to solve discrete tricriteria optimization problems
Journal of Global Optimization, 61 (4) :643–676
20153248.
Speck, R.; Ruprecht, D.; Emmett, M.; Minion, M.; Bolten, Matthias; Krause, R.
A multi-level spectral deferred correction method
BIT, 55 :843-867
20153247.
Speck, R.; Ruprecht, D.; Emmett, M.; Minion, M.; Bolten, M.; Krause, R.
A multi-level spectral deferred correction method
BIT, 55 :843-867
20153246.
Speck, R.; Ruprecht, D.; Emmett, M.; Minion, M.; Bolten, M.; Krause, R.
A multi-level spectral deferred correction method
BIT, 55 :843--867
20153245.
Ehrhardt, Matthias
A Transparent Boundary Condition for an Elastic Bottom in Underwater Acoustics
In I. Dimov and I. Farago and L. Vulkov, Editor, Finite Difference Methods, Theory and Applications: 6th International Conference, FDM 2014, Lozenetz, Bulgaria, June 18-23, 2014, Revised Selected Papers 6Band9045ausLecture Notes in Computer Science, Seite 15--24
Springer International Publishing
In I. Dimov and I. Farago and L. Vulkov, Editor
Herausgeber: Springer
20153244.
Ehrhardt, Matthias
A transparent boundary condition for an elastic bottom in underwater acoustics
Finite Difference Methods, Theory and Applications: 6th International Conference, FDM 2014, Lozenetz, Bulgaria, June 18-23, 2014, Revised Selected Papers, Seite 15–24
Springer International Publishing
Herausgeber: Springer Cham
20153243.
Ehrhardt, Matthias
A transparent boundary condition for an elastic bottom in underwater acoustics
Finite Difference Methods, Theory and Applications: 6th International Conference, FDM 2014, Lozenetz, Bulgaria, June 18-23, 2014, Revised Selected Papers, Seite 15–24
Springer International Publishing
Herausgeber: Springer Cham
2015