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
- 2022
4968.
Schulte, M. Friederike; Izak-Nau, Emilia; Braun, Susanne; Pich, Andrij; Richtering, Walter; Göstl, Robert
Microgels react to force: mechanical properties, syntheses, and force-activated functions
Chemical Society Reviews, 51 (8) :2939--2956
April 2022
ISSN: 1460-47444967.
[german] Gökkus, Yasemin; Tausch, Michael W.
Explorative Studie zur partizipativen und nutzenorientierten Forschung in der Chemiedidaktik
CHEMKON, 29 (3) :117-124
April 20224966.
Bartel, Andreas; Ehrhardt, Matthias
Lagrangian instabilities in thermal convection with stable temperature profiles
arXiv preprint arXiv:2205.03856
April 20224965.
Küng, Robin; Göstl, Robert; Schmidt, Bernd M.
Release of Molecular Cargo from Polymer Systems by Mechanochemistry
Chemistry – A European Journal, 28 (17) :e202103860
März 2022
ISSN: 1521-37654964.
Heyden, von der, Lisa; Wissdorf, Walter; Kurtenbach, Ralf; Kleffmann, Jörg
A relaxed eddy accumulation (REA) LOPAP system for flux measurements of nitrous acid (HONO)
Atmospheric Measurement Techniques, 15 (6) :1983--2000
März 2022
ISSN: 1867-85484963.
Xue, Chaoyang; Ye, Can; Kleffmann, Jörg; Zhang, Chenglong; Catoire, Valéry; Bao, Fengxia; Mellouki, Abdelwahid; Xue, Likun; Chen, Jianmin; Lu, Keding; Zhao, Yong; Liu, Hengde; Guo, Zhaoxin; Mu, Yujing
Atmospheric measurements at Mt. Tai – Part I: HONO formation and its role in the oxidizing capacity of the upper boundary layer
Atmospheric Chemistry and Physics, 22 (5) :3149—3167
März 2022
ISSN: 1680-73244962.
Stratigaki, Maria; Baumann, Christoph; Göstl, Robert
Confocal Microscopy Visualizes Particle–Crack Interactions in Epoxy Composites with Optical Force Probe-Cross-Linked Rubber Particles
Macromolecules, 55 (3) :1060--1066
Februar 2022
ISSN: 0024-92974961.
Villena, Guillermo; Kleffmann, Jörg
A source for the continuous generation of pure and quantifiable HONO mixtures
Atmospheric Measurement Techniques, 15 (3) :627--637
Februar 2022
ISSN: 1867-85484960.
Kalalian, Carmen; Grira, Asma; Illmann, Jan Niklas; Patroescu-Klotz, Iulia; El Dib, Gisèle; Coddeville, Patrice; Canosa, André; Wiesen, Peter; Aazaad, Basheer; Senthilkumar, Lakshmipathi; Roth, Estelle; Tomas, Alexandre; Chakir, Abdelkhaleq
Experimental and Theoretical Studies of Trans-2-Pentenal Atmospheric Ozonolysis
Atmosphere, 13 (2) :291
Februar 2022
ISSN: 2073-44334959.
Cardona, Alejandro L.; Gibilisco, Rodrigo G.; Rivela, Cynthia B.; Blanco, María B.; Patroescu-Klotz, Iulia; Illmann, Niklas; Wiesen, Peter; Teruel, Mariano A.
Kinetics, product distribution and atmospheric implications of the gas-phase oxidation of allyl sulfides by OH radicals
Chemosphere, 288 :132546
Februar 2022
ISSN: 004565354958.
Jäschke, J.; Skrepek, N.; Ehrhardt, M.
Mixed-Dimensional Geometric Coupling of Port-{Hamiltonian} Systems
IMACM preprint 22/04
Februar 20224957.
Meng, Zhuojun; Liu, Qing; Zhang, Yi; Sun, Jing; Yang, Chenjing; Li, Hongyan; Loznik, Mark; Göstl, Robert; Chen, Dong; Wang, Fan; Clark, Noel A.; Zhang, Hongjie; Herrmann, Andreas; Liu, Kai
Highly Stiff and Stretchable DNA Liquid Crystalline Organogels with Super Plasticity, Ultrafast Self-Healing, and Magnetic Response Behaviors
Advanced Materials, 34 (3) :2106208
Januar 2022
ISSN: 1521-40954956.
Zou, Miancheng; Zhao, Pengkun; Huo, Shuaidong; Göstl, Robert; Herrmann, Andreas
Activation of Antibiotic-Grafted Polymer Brushes by Ultrasound
ACS Macro Letters, 11 (1) :15-19
Januar 20224955.
Ballaschk, Frederic; Kirsch, Stefan F.
Oxidations with Iodine(V) Compounds – From Stoichiometric Compounds to Catalysts
In Ishihara, Kazuaki and Muñiz, Kilian, Editor, Iodine Catalysis in Organic Synthesis
Seite 299–334
Herausgeber: Wiley
1 Edition
Januar 2022
299–3344954.
Burgmann, Sebastian; Krämer, Veronika; Dues, Michael; Steinbock, Jonas; Büttner, Lars; Czarske, Juergen; Janoske, Uwe
tm - Technisches Messen, 89 (3) :178--188
20224953.
[german] Zeller, Diana; Bohrmann-Linde, Claudia
#debunk YouTube-Videos - Ein didaktisches Konzept zum Einsatz von Videos im Chemieunterricht zur Stärkung der Digital Scientific Literacy
MNU journal, 75 (03) :197-201
20224952.
Acu, Ana-Maria; Dancs, Madalina; Heilmann, Margareta; Raşa, Ioan; Paşca, Vlad
A Bernstein-Schnabl type operator
Applicable Analysis and Discrete Mathematics, 16(2) :495-507
20224951.
Klass, Friedemann; Gabbana, Alessandro; Bartel, Andreas
A Characteristic Boundary Condition for Multispeed Lattice Boltzmann Methods
Accepted at Commun. Comput. Phys.
20224950.
Arora, Sahiba; Glück, Jochen
A characterization of the individual maximum and anti-maximum principle
20224949.
Fatoorehchi, Hooman; Ehrhardt, Matthias
A combined method for stability analysis of linear time invariant and nonlinear continuous-time control systems based on the Hermite-Fujiwara matrix and Cholesky decomposition
20224948.
Kossaczká, Tatiana; Ehrhardt, Matthias; Günther, Michael
A deep smoothness WENO method with applications in option pricing
In Ehrhardt, Matthias and Günther, Michael, Editor, Progress in Industrial Mathematics at ECMI 2021, Seite 417–423
In Ehrhardt, Matthias and Günther, Michael, Editor
Herausgeber: Springer Cham
20224947.
Kossaczká, Tatiana; Ehrhardt, Matthias; Günther, Michael
A deep smoothness WENO method with applications in option pricing
In Ehrhardt, Matthias and Günther, Michael, Editor, Progress in Industrial Mathematics at ECMI 2021, Seite 417–423
In Ehrhardt, Matthias and Günther, Michael, Editor
Herausgeber: Springer Cham
20224946.
Kossaczká, Tatiana; Ehrhardt, Matthias; Günther, Michael
A deep smoothness WENO method with applications in option pricing
In Ehrhardt, Matthias and Günther, Michael, Editor, Progress in Industrial Mathematics at ECMI 2021, Seite 417–423
In Ehrhardt, Matthias and Günther, Michael, Editor
Herausgeber: Springer Cham
20224945.
Kossaczká, Tatiana; Ehrhardt, Matthias; Günther, Michael
A deep smoothness WENO method with applications in option pricing
Progress in Industrial Mathematics at ECMI 2021
Seite 417--423
Herausgeber: Springer International Publishing Cham
2022
417--4234944.
Edeko, Nikolai; Kreidler, Henrik; Nagel, Rainer
A dynamical proof of the van der Corput inequality
Dynamical Systems, 37 :648-665
2022
