Applied and Computational Mathematics (ACM)

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

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

Cooperation

Former and ongoing projects

Publications



2025

5492.

Ocqueteau, Vicente; Tucsnak, Marius
On an Initial Value Problem Describing the Small Oscillations of a Floating Cylinder
April 2025

5491.


Solid-Supported Iodine(V) Reagents in Organic Synthesis
Chemistry - A European Journal, 31 :e202500670
03 2025
Herausgeber: Wiley
ISSN: 1521-3765

5490.

[german] Grandrath, Rebecca; Wiebel, Michelle; Bensberg, Kathrin; Schebb, Nils Helge; Bohrmann-Linde, Claudia
Aus der Schale in die Schule
Nachrichten aus der Chemie, 73 (3) :10-12
März 2025

5489.

Storch, Sonja; Campagna, Davide; Aydonat, Simay; Göstl, Robert
Mechanochemical generation of nitrogen-centred radicals for the formation of tertiary amines in polymers
RSC Mechanochemistry, 2 (2) :240-245
März 2025

5488.


Aus der Schale in die Schule
Nachrichten aus der Chemie, 73 :10-12
02 2025
Herausgeber: Wiley
ISSN: 1868-0054

5487.

Cornelius, Soraya
„Erklärvideos erklären“- Entwicklung und Erprobung eines interaktiven und digitalen Selbstlernbuchs zum schrittweisen Kompetenzerwerb für die Erklärvideoproduktion im Chemieunterricht (explorative Studie)
2025

5486.

Krieger, Emil; Schweitzer, Marcel
A general framework for Krylov ODE residuals with applications to randomized Krylov methods
2025

5485.

Clevenhaus, A.; Totzeck, C.; Ehrhardt, M.
A Space Mapping approach for the calibration of financial models with the application to the Heston model
2025

5484.

Gaul, Daniela; Klamroth, Kathrin; Pfeiffer, Christian; Stiglmayr, Michael; Schulz, Arne
A Tight Formulation for the Dial-a-Ride Problem
European Journal of Operational Research, 321 (2) :363-382
2025
ISSN: 0377-2217

5483.

Bauß, Julius; Stiglmayr, Michael
Adapting Branching and Queuing for Multi-objective Branch and Bound
In Voigt, G., Fliedner, M., Haase, K., Brüggemann, W., Hoberg, K., Meissner, J., Editor, Operations Research Proceedings 2023. OR 2023. Lecture Notes in Operations Research
In Voigt, G., Fliedner, M., Haase, K., Brüggemann, W., Hoberg, K., Meissner, J., Editor
Herausgeber: Springer, Cham
2025

5482.

Könen, David; Stiglmayr, Michael
An output-polynomial time algorithm to determine all supported efficient solutions for multi-objective integer network flow problems
Discrete Applied Mathematics, 376 :1-14
2025
Herausgeber: Elsevier BV
ISSN: 0166-218X

5481.

Frommer, Andreas; Rinelli, Michele; Schweitzer, Marcel
Analysis of stochastic probing methods for estimating the trace of functions of sparse symmetric matrices
Math. Comp., 94 :801-823
2025

5480.

Hoffe, Leon; Ulutas, Berna; Klamroth, Kathrin; Bracke, Stefan
Assessing the effectiveness and efficiency of selected solution approaches for two-dimensional stock cutting problems (Part III): Hybrid Approach For Printed Circuit Boards
AUTOMATION 2025: Conference on Automation — Innovations and Future Perspectives
2025

5479.

Abel, Ulrich; Acu, Ana Maria; Heilmann, Margareta; Raşa, Ioan
Asymptotic expansions for generalized Bernstein-Durrmeyer and genuine Bernstein-Durrmeyer operators
2025

5478.

Kiesling, Elisabeth; Bohrmann-Linde, Claudia
Carbon Capture and Storage - Nachweis von adsorbiertem Kohlenstoffdioxid
Naturwissenschaften im Unterricht Chemie, 1/25 :Versuchskarteikarte
Februar 2025

5477.

Clément, François; Doerr, Carola; Klamroth, Kathrin; Paquete, Luís
Constructing Optimal Star Discrepancy Sets
accepted in Proceedings of the AMS
2025

5476.

Liu, Qian; Wang, Miao; Chen, Cheng; Zhao, Xiaowei
Current-Limiting Control Design for Grid-Forming Capability Enhancement of IBRs Under Asymmetric Grid Disturbances
IEEE Transactions on Power Electronics :1-17
November 2025
Herausgeber: IEEE
ISSN: 1941-0107

5475.

Schaller, Manuel; Schmitz, Merlin; Jacob, Birgit; Farkas, Bálint
Dissipativity-based time domain decomposition for optimal control of hyperbolic {PDE}s
2025

5474.

Kunze, Markus; Mui, Jonathan; Ploss, David
Elliptic operators with non-local Wentzell-Robin boundary conditions
2025

5473.

Song, Yongcun; Wang, Ziqi; Zuazua, Enrique
FedADMM-InSa: An Inexact and Self-Adaptive ADMM for Federated Learning
Neural Network, 181
Januar 2025

5472.

Kienitz, J; Moodliyar, L
Gaussian views explained
Wilmott, 2025 (135) :72–77
2025
Herausgeber: Wilmott Magazine

5471.

Xu, Zhuo; Tucsnak, Marius
Global Exponential Stabilization for a Simplified Fluid-Particle Interaction System
Januar 2025

5470.

Bartel, Andreas; Schaller, Manuel
Goal-oriented time adaptivity for port-Hamiltonian systems
Journal of Computational and Applied Mathematics, 461 :116450
2025
ISSN: 0377-0427

5469.

Schäfers, Kevin; Finkenrath, Jacob; Günther, Michael; Knechtli, Francesco
Hessian-free force-gradient integrators
Computer Physics Communications, 309 :109478
2025
ISSN: 0010-4655

5468.

Schäfers, Kevin; Finkenrath, Jacob; Günther, Michael; Knechtli, Francesco
Hessian-free force-gradient integrators
Computer Physics Communications, 309 :109478
2025
ISSN: 0010-4655