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
- 2023
5218.
Kähne, B.; Clemens, M.
A ROW-Type Method for GPU-Accelerated Large-Scale Finite Element Simulations of Nonlinear Eddy Current Problems
The 13th International Symposium on Electric and Magnetic Fields (EMF 2023)
Marseilles, France
Mai 20235217.
Baptista, Andrea; Gibilisco, Rodrigo G.; Patroescu-Klotz, Iulia; Illmann, Niklas; Wiesen, Peter; Blanco, María B.; Teruel, Mariano A.
Product study of the reactions of γ-caprolactone and γ-heptalactone initiated by OH radicals at 298 K and atmospheric pressure: Formation of acyl peroxynitrates (APN).
Chemosphere, 323 :138156
Mai 2023
ISSN: 004565355216.
Bond, Amelia M. H.; Frey, Markus M.; Kaiser, Jan; Kleffmann, Jörg; Jones, Anna E.; Squires, Freya A.
Snowpack nitrate photolysis drives the summertime atmospheric nitrous acid (HONO) budget in coastal Antarctica
Atmospheric Chemistry and Physics, 23 (9) :5533—5550
Mai 2023
ISSN: 1680-73245215.
Haussmann, N.; Stroka, S.; Clemens, M.
Reduction of the Numerical Error in High-Resolution Low-Frequency Magnetic-Field Exposure Scenarios of Human Models Utilizing Smoothing Methods
The 13th International Symposium on Electric and Magnetic Fields (EMF 2023)
Marseilles, France, 29.-31.08.2023
April 20235214.
Zhou, Yu; Centeno, Silvia P.; Zhang, Kuan; Zheng, Lifei; Göstl, Robert; Herrmann, Andreas
Fracture Detection in Bio-Glues with Fluorescent-Protein-Based Optical Force Probes
Advanced Materials, 35 (16) :2210052
April 2023
ISSN: 1521-40955213.
Bensberg, Kathrin; Kunz, K.; Kirsch, Stefan F.
Thermolysis of Geminal Diazido Malonamides: Simple Access to Tetrazoles and Functionalization of In Situ Formed Isocyanates
European Journal of Organic Chemistry, 26 (18) :e2023002
April 2023
Herausgeber: Wiley
ISSN: 1434-193X5212.
Küng, Robin; Germann, Anne; Krüsmann, Marcel; Niggemann, Louisa P.; Meisner, Jan; Karg, Matthias; Göstl, Robert; Schmidt, Bernd M.
Mechanoresponsive Metal-Organic Cage-Crosslinked Polymer Hydrogels
Chemistry – A European Journal, 29 (18) :e202300079
März 2023
ISSN: 1521-37655211.
Braun, Feodor; Jaschinski, M.; Kirsch, Stefan F.; Schomäcker, Klaus
Synthesis and evaluation of radioiodinated estrogens for diagnosis and therapy of male urogenital tumours
Organic & Biomolecular Chemistry, 21 :3090-3095
März 2023
Herausgeber: RSC
ISSN: 1477-05395210.
[german] Grandrath, Rebecca; Bohrmann-Linde, Claudia
Dem Apfel ans Leder
Nachrichten aus der Chemie, 71 :12-14
März 20235209.
Ehrhardt, Matthias
Experimental observation and theoretical analysis of the low-frequency source interferogram and hologram in shallow water
Journal of Sound and Vibration, 544 :117388
März 2023
Herausgeber: Academic Press5208.
Wiesen, Peter; Illmann, Jan Niklas
Umweltchemie: Methan in der Atmosphäre
Nachrichten aus der Chemie, 71 (2) :70—73
Februar 2023
ISSN: 1439-9598, 1868-00545207.
Metzmacher, Andreas; Burgmann, Sebastian; Janoske, Uwe
$\mu$PIV measurements of the phase-averaged velocity distribution within wavy films
Experiments in Fluids, 64 (4) :81
2023
Herausgeber: Springer Berlin Heidelberg Berlin/Heidelberg5206.
Ehrhardt, Matthias
3D Modeling of sound field hologram of moving source in presence of internal waves causing horizontal refraction.
Preprint IMACM
2023
Herausgeber: Bergische Universität Wuppertal5205.
Ehrhardt, Matthias
3D Modeling of sound field hologram of moving source in presence of internal waves causing horizontal refraction.
Preprint IMACM
2023
Herausgeber: Bergische Universität Wuppertal5204.
Klass, Friedemann; Gabbana, Alessandro; Bartel, Andreas
A characteristic boundary condition for multispeed lattice Boltzmann methods
Communications in Computational Physics, 33 (1) :101–117
2023
Herausgeber: Global Science Press5203.
Fatoorehchi, Hooman; Ehrhardt, Matthias
A combined method for stability analysis of linear time invariant control systems based on Hermite-Fujiwara matrix and Cholesky decomposition
The Canadian Journal of Chemical Engineering, 101 (12) :7043–7052
2023
Herausgeber: John Wiley & Sons5202.
Fatoorehchi, Hooman; Ehrhardt, Matthias
A combined method for stability analysis of linear time invariant control systems based on Hermite-Fujiwara matrix and Cholesky decomposition
The Canadian Journal of Chemical Engineering, 101 (12) :7043–7052
2023
Herausgeber: John Wiley & Sons5201.
Zargaran, Amin; Dolshanskiy, Wladislaw; Stepanyuk, Alexey; Pauer, Werner; Janoske, Uwe
A hybrid approach based on Lagrangian particles and immersed-boundary method to characterize rotor--stator mixing systems for high viscous mixtures
Chemical Engineering Journal, 473 :145062
2023
Herausgeber: Elsevier5200.
Fatoorehchi, Hooman; Ehrhardt, Matthias
A new method for stability analysis of linear time-invariant systems and continuous-time nonlinear systems with application to process dynamics and control
Preprint IMACM
20235199.
Fatoorehchi, Hooman; Ehrhardt, Matthias
A new method for stability analysis of linear time-invariant systems and continuous-time nonlinear systems with application to process dynamics and control
Preprint IMACM
20235198.
Fatoorehchi, Hooman; Ehrhardt, Matthias
A new method for stability analysis of linear time-invariant systems and continuous-time nonlinear systems with application to process dynamics and control
20235197.
Bolten, Matthias; Ekström, S.-E.; Furci, I.; Serra-Capizzano, S.
A note on the spectral analysis of matrix sequences via GLT momentary symbols: from all-at-once solution of parabolic problems to distributed fractional order matrices
Electron. Trans. Numer. Anal., 58 :136--163
20235196.
Edeko, Nikolai; Jamneshan, Asgar; Kreidler, Henrik
A Peter-Weyl theorem for compact group bundles and the geometric representation of relatively ergodic compact extensions
20235195.
Schlimbach, Ricarda; Khosrawi-Rad, Bijan; Grogorick, Linda; Becker, Felix; Strohmann, Timo; Siemon, Dominik; Robra-Bissantz, Susanne
A Teaching Framework for the Methodically Versatile DSR Education of Master Students
Journal of Information Systems Education, 34 (3) :333-346
20235194.
Bauß, Julius; Parragh, Sophie N.; Stiglmayr, Michael
Adaptive Improvements of Multi-objective Branch and Bound
2023
