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
- 2024
5200.
Kossaczká, Tatiana; Jagtap, Ameya D; Ehrhardt, Matthias
Deep smoothness weighted essentially non-oscillatory method for two-dimensional hyperbolic conservation laws: A deep learning approach for learning smoothness indicators
Physics of Fluids, 36 (3)
2024
Herausgeber: AIP Publishing5199.
Kossaczká, Tatiana; Jagtap, Ameya D; Ehrhardt, Matthias
Deep smoothness WENO method for two-dimensional hyperbolic conservation laws: A deep learning approach for learning smoothness indicators
Physics of Fluid, 36 (3) :036603
2024
Herausgeber: AIP Publishing5198.
Kossaczká, Tatiana; Jagtap, Ameya D; Ehrhardt, Matthias
Deep smoothness WENO method for two-dimensional hyperbolic conservation laws: A deep learning approach for learning smoothness indicators
Physics of Fluid, 36 (3) :036603
2024
Herausgeber: AIP Publishing5197.
Stiglmayr, Michael; Uhlemeyer, Svenja; Uhlemeyer, Björn; Zdrallek, Markus
Determining Cost-Efficient Controls of Electrical Energy Storages Using Dynamic Programming
Journal of Mathematics in Industry
20245196.
Ehrhardt, M.; Kruse, T.; Tordeux, A.
Dynamics of a Stochastic port-{H}amiltonian Self-Driven Agent Model in One Dimension
ESAIM: Math. Model. Numer. Anal.
20245195.
Efficient and Simple Extraction Protocol for Triterpenic Acids from Apples
Journal of Chemical Education, 101 :2087-2093
April 2024
Herausgeber: ACS5194.
Ehrhardt, Matthias; Kozitskiy, Sergey B
A generalization of the split-step Padé method to the case of coupled acoustic modes equation in a 3D waveguide
Journal of Sound and Vibration :118304
2024
Herausgeber: Elsevier5193.
Holzenkamp, Matthias; Lyu, Dongyu; Kleinekathöfer, Ulrich; Zaspel, Peter
Evaluation of uncertainty estimations for Gaussian process regression based machine learning interatomic potentials.
20245192.
Gaul, Daniela
Exact and Heuristic Methods for Dial-a-Ride Problems
Dissertation
Dissertation
Bergische Universität Wuppertal
20245191.
Lyu, Dongyu; Holzenkamp, Matthias; Vinod, Vivin; Holtkamp, Yannick M.; Maity, Sayan; Salazar, Carlos R.; Kleinekathöfer, Ulrich; Zaspel, Peter
Excitation Energy Transfer between Porphyrin Dyes on a Clay Surface: A study employing Multifidelity Machine Learning.
20245190.
Kienitz, Jörg
Exciting times are ahead - Gaussian views and yield curve extrapolation
Wilmott, 2024 (134) :46–50
2024
Herausgeber: Wilmott Magazine5189.
[german] Zeller, Diana; Bohrmann-Linde, Claudia
Falschinformationen in Videos? Mit dem Konzept KriViNat die Kompetenz der Informationsbewertung stärken
In Bohrmann-Linde, C.; Gökkus, Y.; Meuter, N.; Zeller, D., Editor, Band Netzwerk Digitalisierter Chemieunterricht. Sammelband NeDiChe-Treff 2022
Seite 9-15
Herausgeber: Chemiedidaktik. Bergische Universität Wuppertal
2024
9-155188.
Bartel, Andreas; Schaller, Manuel
Goal-oriented time adaptivity for port-{H}amiltonian systems
2024- 2023
5187.
Haussmann, N.; Stroka, S.; Mazaheri, S.; Clemens, M.
Using Point Clouds for Material Properties Smoothing in Low-Frequency Numerical Dosimetry Simulations
21st Biennial IEEE Conference on Electromagnetic Field Computation (CEFC 2024)
Jeju, South Korea
Dezember 20235186.
Kähne, B.; Clemens, M.
A GPU Accelerated Semi-Implicit Method for Large-Scale Nonlinear Eddy-Current Problems Using Adaptive Time Step Control
21st Biennial IEEE Conference on Electromagnetic Field Computation (CEFC 2024)
Jeju, South Korea
Dezember 20235185.
Gernandt, Hannes; Hinsen, Dorothea; Cherifi, Karim
The difference between port-Hamiltonian, passive and positive real descriptor systems
Mathematics of Control, Signals, and Systems
Dezember 20235184.
Abel, Ulrich; Acu, Ana Maria; Heilmann, Margareta; Raşa, Ioan
Voronovskaja formula for Aldaz–Kounchev–Render operators: uniform convergence
Analysis and Mathematical Physics, 14 (1)
Dezember 2023
ISSN: 1664-235X5183.
Stroka, S.; Kasolis, F.; Haussmann, N.; Clemens, M.
Efficient Low-Frequency Human Exposure Assessment with the Maximum Entropy Snapshot Sampling
21st Biennial IEEE Conference on Electromagnetic Field Computation (CEFC 2024)
Jeju, Korea
November 20235182.
Xuan, Mingjun; Fan, Jilin; Khiêm, Vu Ngoc; Zou, Miancheng; Brenske, Kai-Oliver; Mourran, Ahmed; Vinokur, Rostislav; Zheng, Lifei; Itskov, Mikhail; Göstl, Robert; Herrmann, Andreas
Polymer Mechanochemistry in Microbubbles
Advanced Materials, 35 (47) :2305130
November 2023
ISSN: 1521-40955181.
Stroka, S.; Haussmann, N.; Clemens, M.
Efficient Assessment of High-Resolution Low-Frequency Magnetic Field Exposure Scenarios Using Reduced Order Models
15th Scientific Computing in Electrical Engineering (SCEE 2024)
Darmstadt, Germany
November 20235180.
[german] Kiesling, Elisabeth; Kremer, Richard; Pereira Vaz, Nuno; Venzlaff, Julian; Bohrmann-Linde, Claudia
Wege aus der Klimakrise – ein BNE-Schülerlaborangebot mit mehrdimensionalem Zugang
MNU Journal, 76 (06/2023) :464 - 471
November 2023
ISSN: 0025-58665179.
Alameddine, Jean-Marco; Albrecht, Johannes; Dembinski, Hans; Gutjahr, Pascal; Kampert, Karl-Heinz; Rhode, Wolfgang; Sackel, Maximilian; Sandrock, Alexander; Soedingrekso, Jan
Improvements in charged lepton and photon propagation for the software PROPOSAL
November 20235178.
[german] Grandrath, Rebecca
Videoschnitt für Einsteiger:innen
Unterricht Biologie - Das Schülerarbeitsheft, 51 :32-36
November 20235177.
He, Siyang; Schog, Simon; Chen, Ying; Ji, Yuxin; Panitz, Sinan; Richtering, Walter; Göstl, Robert
Photoinduced Mechanical Cloaking of Diarylethene-Crosslinked Microgels
Advanced Materials, 35 (41) :2305845
Oktober 2023
ISSN: 1521-40955176.
Phenanthro[9,10‑d]imidazoles: An Unexpected Synthetic Route
Synthesis, 55 (24) :4224-4230
Oktober 2023
Herausgeber: Thieme
ISSN: 0039-7881