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
- 2021
4491.
Donatelli, Marco; Ferrari, Paola; Furci, Isabella; Serra-Capizzano, Stefano; Sesana, Debora
Multigrid methods for block-Toeplitz linear systems: convergence analysis and applications
Numer. Linear Algebra Appl., 28 (4) :Paper No. e2356, 20
20214490.
Donatelli, Marco; Ferrari, Paola; Furci, Isabella; Serra-Capizzano, Stefano; Sesana, Debora
Multigrid methods for block-Toeplitz linear systems: convergence analysis and applications
Numer. Linear Algebra Appl., 28 (4) :Paper No. e2356, 20
2021
ISSN: 1070-53254489.
Donatelli, Marco; Ferrari, Paola; Furci, Isabella; Serra-Capizzano, Stefano; Sesana, Debora
Multigrid methods for block-Toeplitz linear systems: convergence analysis and applications
Numer. Linear Algebra Appl., 28 (4) :Paper No. e2356, 20
2021
ISSN: 1070-53254488.
Hutzenthaler, Martin; Jentzen, Arnulf; Kruse, Thomas; others
Multilevel Picard iterations for solving smooth semilinear parabolic heat equations
Partial Differential Equations and Applications, 2 (6) :1--31
2021
Herausgeber: Springer4487.
Hutzenthaler, Martin; Jentzen, Arnulf; Kruse, Thomas; others
Multilevel Picard iterations for solving smooth semilinear parabolic heat equations
Partial Differential Equations and Applications, 2 (6) :1–31
2021
Herausgeber: Springer International Publishing4486.
Ferrari, Paola; Furci, Isabella; Serra-Capizzano, Stefano
Multilevel symmetrized Toeplitz structures and spectral distribution results for the related matrix sequences
Electron. J. Linear Algebra, 37 :370-386
20214485.
Ferrari, Paola; Furci, Isabella; Serra-Capizzano, Stefano
Multilevel symmetrized Toeplitz structures and spectral distribution results for the related matrix sequences
Electron. J. Linear Algebra, 37 :370-386
20214484.
Ferrari, Paola; Furci, Isabella; Serra-Capizzano, Stefano
Multilevel symmetrized Toeplitz structures and spectral distribution results for the related matrix sequences
Electron. J. Linear Algebra, 37 :370-386
20214483.
Hachtel, Christoph; Bartel, Andreas; Günther, Michael; Sandu, Adrian
Multirate implicit Euler schemes for a class of differential--algebraic equations of index-1
Journal of Computational and Applied Mathematics, 387 :112499
2021
Herausgeber: North-Holland4482.
Hachtel, Christoph; Bartel, Andreas; Günther, Michael; Sandu, Adrian
Multirate implicit Euler schemes for a class of differential-algebraic equations of index-1
Journal of Computational and Applied Mathematics, 387 :112499
2021
Herausgeber: North-Holland4481.
Hachtel, Christoph; Bartel, Andreas; Günther, Michael; Sandu, Adrian
Multirate implicit Euler schemes for a class of differential-algebraic equations of index-1
Journal of Computational and Applied Mathematics, 387 :112499
2021
Herausgeber: North-Holland4480.
Günther, Michael; Sandu, Adrian
Multirate linearly-implicit GARK schemes
BIT Numerical Mathematics :1--33
2021
Herausgeber: Springer Netherlands4479.
Lübke, Marco
Neuartige multifunktionelle Tenside auf Basis nachwachsender Rohstoffe
20214478.
Claus, L.; Bolten, Matthias
Non-overlapping block smoothers for the Stokes equations
Num. Lin. Alg. Appl., 28 (6) :e2389
20214477.
Claus, L.; Bolten, M.
Non-overlapping block smoothers for the Stokes equations
Num. Lin. Alg. Appl., 28 (6) :e2389
20214476.
Claus, L.; Bolten, M.
Non-overlapping block smoothers for the Stokes equations
Num. Lin. Alg. Appl., 28 (6) :e2389
20214475.
Eichfelder, Gabriele; Klamroth, Kathrin; Niebling, Julia
Nonconvex constrained optimization by a filtering branch and bound
Journal of Global Optimization, 80 :31-61
20214474.
Mironchenko, Andrii; Kawan, Christoph; Glück, Jochen
Nonlinear small-gain theorems for input-to-state stability of infinite interconnections
Math. Control Signals Systems, 33 (4) :573--615
20214473.
Krämer, Veronika; Barwari, Beawer; Burgmann, Sebastian; Rohde, Martin; Rentschler, Simon; Holzknecht, Christopher; Gmelin, Christoph; Janoske, Uwe
Numerical analysis of an adhering droplet applying an adapted feedback deceleration technique
International Journal of Multiphase Flow, 145 :103808
Dezember 2021
Herausgeber: Elsevier {BV}4472.
Jacob, Birgit; Zwart, Hans
Observability for port-Hamiltonian systems
European Control Conference (ECC) :2052-2057
20214471.
Markert, Clara; Thinius, Marco; Lehmann, Laura; Heintz, Chris; Stappert, Florian; Wissdorf, Walter; Kersten, Hendrik; Benter, Thorsten; Schneider, Bradley B.; Covey, Thomas R.
Observation of charged droplets from electrospray ionization (ESI) plumes in API mass spectrometers
Analytical and Bioanalytical Chemistry
Juli 2021
ISSN: 1618-2642, 1618-26504470.
Friedhoff, S.; Southworth, B. S.
On "optimal" $h$-independent convergence of parareal and multigrid-reduction-in-time using Runge-Kutta time integration
Numer. Linear Algebra Appl., 28 (3)
20214469.
Friedhoff, S.; Southworth, B. S.
On "optimal" $h$-independent convergence of parareal and multigrid-reduction-in-time using Runge-Kutta time integration
Numer. Linear Algebra Appl., 28 (3) :Paper No. e2301, 30
20214468.
Friedhoff, S.; Southworth, B. S.
On "optimal" $h$-independent convergence of parareal and multigrid-reduction-in-time using Runge-Kutta time integration
Numer. Linear Algebra Appl., 28 (3) :Paper No. e2301, 30
20214467.
Farkas, Bálint; Friesen, Martin; Rüdiger, Barbara; Schroers, Dennis
On a class of stochastic partial differential equations with multiple invariant measures
NoDEA
2021