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
- 2025
5511.
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
20255510.
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
20255509.
Abel, Ulrich; Acu, Ana Maria; Heilmann, Margareta; Raşa, Ioan
Asymptotic expansions for generalized Bernstein-Durrmeyer and genuine Bernstein-Durrmeyer operators
20255508.
Kiesling, Elisabeth; Bohrmann-Linde, Claudia
Carbon Capture and Storage - Nachweis von adsorbiertem Kohlenstoffdioxid
Naturwissenschaften im Unterricht Chemie, 1/25 :Versuchskarteikarte
Februar 20255507.
Clément, François; Doerr, Carola; Klamroth, Kathrin; Paquete, Luís
Constructing Optimal Star Discrepancy Sets
accepted in Proceedings of the AMS
20255506.
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: 1941-01075505.
Schaller, Manuel; Schmitz, Merlin; Jacob, Birgit; Farkas, Bálint
Dissipativity-based time domain decomposition for optimal control of hyperbolic {PDE}s
20255504.
Kunze, Markus; Mui, Jonathan; Ploss, David
Elliptic operators with non-local Wentzell-Robin boundary conditions
20255503.
Song, Yongcun; Wang, Ziqi; Zuazua, Enrique
FedADMM-InSa: An Inexact and Self-Adaptive ADMM for Federated Learning
Neural Network, 181
Januar 20255502.
Kienitz, J; Moodliyar, L
Gaussian views explained
Wilmott, 2025 (135) :72–77
2025
Herausgeber: Wilmott Magazine5501.
Xu, Zhuo; Tucsnak, Marius
Global Exponential Stabilization for a Simplified Fluid-Particle Interaction System
Januar 20255500.
Bartel, Andreas; Schaller, Manuel
Goal-oriented time adaptivity for port-Hamiltonian systems
Journal of Computational and Applied Mathematics, 461 :116450
2025
ISSN: 0377-04275499.
Schäfers, Kevin; Finkenrath, Jacob; Günther, Michael; Knechtli, Francesco
Hessian-free force-gradient integrators
Computer Physics Communications, 309 :109478
2025
ISSN: 0010-46555498.
Schäfers, Kevin; Finkenrath, Jacob; Günther, Michael; Knechtli, Francesco
Hessian-free force-gradient integrators
Computer Physics Communications, 309 :109478
2025
ISSN: 0010-46555497.
Schäfers, Kevin; Finkenrath, Jacob; Günther, Michael; Knechtli, Francesco
Hessian-free force-gradient integrators and their application to lattice QCD simulations
PoS, LATTICE2024 :025
20255496.
Schäfers, Kevin; Finkenrath, Jacob; Günther, Michael; Knechtli, Francesco
Hessian-free force-gradient integrators and their application to lattice QCD simulations
PoS, LATTICE2024 :025
20255495.
Krhac, Kaja; Schuller, Frederic P.; Stramigioli, Stefano
Hybrid Schrödinger-Liouville and projective dynamics
20255494.
Shaju, K.; Laepple, T.; Hirsch, N.; Zaspel, P.
Ice borehole thermometry: Sensor placement using greedy optimal sampling
EGUsphere, 2025 :1—25
20255493.
Vinod, Vivin; Zaspel, Peter
Investigating Data Hierarchies in Multifidelity Machine Learning for Excitation Energies
J. Chem. Theory Comput., 21 (6) :3077-3091
20255492.
Rajkovic, Michelle; Benter, Thorsten; Wissdorf, Walter
Investigation of Surface-Induced Dissociation Processes via Molecular Dynamics Simulations of Wall Collisions of Large Droplets Produced by Electrospray Ionization
Journal of the American Society for Mass Spectrometry, 36 (4) :760—770
April 2025
ISSN: 1044-0305, 1879-11235491.
Abel, Ulrich; Acu, Ana Maria; Heilmann, Margareta; Raşa, Ioan
Kernels for composition of positive linear operators
20255490.
[german] Grandrath, Rebecca; Orhan, Nalan; Bohrmann-Linde, Claudia
Konzeption einer Projektwoche zu den Themen Food Waste und Food Loss für die gymnasiale Oberstufe
In Andreas Keil, Annika Hanau und Julian Dietze (Hg.): BNE in der Lehrkräftebildung. Erkenntnisse aus Forschung und Praxis., Editor
Seite 315-325
Herausgeber: Waxmann
Mai 2025
315-3255489.
Khosrawi-Rad, Bijan; Keller, Paul; Grogorick, Linda; Benner, Dennis; Janson, Andreas; Robra-Bissantz, Susanne
Let's Play with AI! A 2x2 Experiment on Collaborative vs. Competitive Game Elements for Pedagogical Conversational Agents
Pre-ICIS SIG Services Workshop on Synergizing Service Ecosystems with AI
Bangkok, Thailand
20255488.
[german] Cornelius, Soraya; Bohrmann-Linde, Claudia
Motivieren mit (Teil-)Aufgaben zur Erklärvideoproduktion im Chemieunterricht
In Johannes Huwer, Timm Wilke, Amitabh Banerji, Editor, Band Progress in Digitalisation in Chemistry Education 2024. Digitales Lehren und Lernen an Hochschule und Schule im Fach Chemie
Seite 37-42
Herausgeber: Waxmann-Verlag, Münster New York
2025
37-42ISBN: 978-3-8188-0042-0
5487.
Finster, Rebecca; Grogorick, Linda; Robra-Bissantz, Susanne
Navigation im Cyberraum: Die NIS2-Umsetzung in der öffentlichen Verwaltung - mit KOMPASS und SEXTANT
Fachtagung Rechts- und Verwaltungsinformatik (RVI)
Hamburg
2025