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



2021

4693.

[german] Grandrath, Rebecca; Bohrmann-Linde, Claudia
Experimentieren mit interaktiven E-Books zu mikrobiellen Brennstoffzellen - Lerneinheiten für die Sekundarstufen I und II
MNU, 74 (3) :235-240
Juni 2021

4692.

Tausch, Michael W.; Bohrmann-Linde, Claudia
Nachhaltige Chemie mit Licht - Experimentelle Zugänge in digitalen Medien
CHEMKON, 28 (4) :147--154
Juni 2021

4691.

Zang, M.; Haussmann, N.; Stroka, S.; Mease, R.; Clemens, M.; Burkert, A.; Popp, A.; Schmuelling, B.
Personenschutz bei induktivem Laden von Fahrzeugbatterien -- Ansätze zur praktikablen Echtzeitbestimmung der magneto-quasistatischen Körperexposition
Wissenschaftsforum Mobilität, Duisburg, 17.06.2021. Full paper submitted, 2021.
Juni 2021

4690.


Towards a Common $t\bar{t}$ Monte-Carlo Sample for ATLAS and CMS
CERN, Geneva
Juni 2021

4689.

Göstl, Robert
Machen, zerstören, besser machen
Nachrichten aus der Chemie, 69 (5) :78--79
Mai 2021
ISSN: 1868-0054

4688.

Grira, A.; Kalalian, C.; Illmann, J.N.; Patroescu-Klotz, I.; El Dib, G.; Coddeville, P.; Canosa, A.; Coeur, C.; Wiesen, P.; Roth, E.; Chakir, A.; Tomas, A.
Gas-phase ozonolysis of trans-2-hexenal: Kinetics, products, mechanism and SOA formation
Atmospheric Environment, 253 :118344
Mai 2021
ISSN: 13522310

4687.

Kroflič, Ana; Anders, Janine; Drventić, Ivana; Mettke, Peter; Böge, Olaf; Mutzel, Anke; Kleffmann, Jörg; Herrmann, Hartmut
Guaiacol Nitration in a Simulated Atmospheric Aerosol with an Emphasis on Atmospheric Nitrophenol Formation Mechanisms
ACS Earth and Space Chemistry, 5 (5) :1083--1093
Mai 2021
ISSN: 2472-3452, 2472-3452

4686.

[german] Zeller, Diana; Gökkus, Yasemin; Kremer, Richard; Bohrmann-Linde, Claudia
H5P-Videos in der chemiedidaktischen Lehre
CHEMKON, 28 (6) :245-248
Mai 2021

4685.

[english] Hoffmann, Heiko; Tausch, Michael W.
Intermolecular Photoredox Coupling: Alternative to Norrish Type II Reaction and Yang Cyclization in Ketones with γ-C-Bonds
European Journal of Organic Chemistry
Mai 2021

4684.

[german] Zeller, Diana; Grandrath, Rebecca; Bohrmann-Linde, Claudia
Digitale Lehr- und Lerntools für den Chemieunterricht mithilfe von Prezi und E-Books. Teil 3.
Chemie & Schule, 36 (2) :9-13
April 2021

4683.

Shi, Zhiyuan; Song, Qingchuan; Göstl, Robert; Herrmann, Andreas
Mechanochemical activation of disulfide-based multifunctional polymers for theranostic drug release
Chemical Science, 12 (5) :1668--1674
Februar 2021
ISSN: 2041-6539

4682.

Sun, Jing; Ma, Chao; Maity, Sourav; Wang, Fan; Zhou, Yu; Portale, Giuseppe; Göstl, Robert; Roos, Wouter H.; Zhang, Hongjie; Liu, Kai; Herrmann, Andreas
Reversibly Photo-Modulating Mechanical Stiffness and Toughness of Bioengineered Protein Fibers
Angewandte Chemie International Edition, 133 (6) :3259--3265
Februar 2021
ISSN: 1521-3757

4681.

Huo, Shuaidong; Zhao, Pengkun; Shi, Zhiyuan; Zou, Miancheng; Yang, Xintong; Warszawik, Eliza; Loznik, Mark; Göstl, Robert; Herrmann, Andreas
Mechanochemical bond scission for the activation of drugs
Nature Chemistry, 13 (2) :131--139
Februar 2021
ISSN: 1755-4349

4680.

Zhou, Yu; Huo, Shuaidong; Loznik, Mark; Göstl, Robert; Boersma, Arnold J.; Herrmann, Andreas
Controlling Optical and Catalytic Activity of Genetically Engineered Proteins by Ultrasound
Angewandte Chemie International Edition, 60 (3) :1493--1497
Januar 2021
ISSN: 1521-3773

4679.

Zhou, Yu; Huo, Shuaidong; Loznik, Mark; Göstl, Robert; Boersma, Arnold J.; Herrmann, Andreas
Kontrolle über die optische und katalytische Aktivität gentechnisch hergestellter Proteine mit Ultraschall
Angewandte Chemie, 133 (3) :1515--1519
Januar 2021
ISSN: 1521-3757

4678.

Celik, Ibrahim E.; Kirsch, Stefan F.
Reactivity of Organic Geminal Diazides at Tetrahedral Carbons
European Journal of Organic Chemistry, 2021 :53–63
Januar 2021
ISSN: 1434-193X, 1099-0690

4677.

Bannenberg, MWFM; Ciccazzo, A
A Combination of Model Order Reduction and Multirate Techniques for Coupled Dynamical Systems
Scientific Computing in Electrical Engineering: SCEE 2020, Eindhoven, The Netherlands, February 2020, Seite 191–199
Herausgeber: Springer International Publishing
2021

4676.

Bannenberg, MWFM; Ciccazzo, A
A Combination of Model Order Reduction and Multirate Techniques for Coupled Dynamical Systems
Scientific Computing in Electrical Engineering: SCEE 2020, Eindhoven, The Netherlands, February 2020
Seite 191--199
Herausgeber: Springer International Publishing Cham
2021
191--199

4675.

Bannenberg, MWFM; Ciccazzo, A
A Combination of Model Order Reduction and Multirate Techniques for Coupled Dynamical Systems
Scientific Computing in Electrical Engineering: SCEE 2020, Eindhoven, The Netherlands, February 2020, Seite 191–199
Herausgeber: Springer International Publishing
2021

4674.

Pauly, Dirk; Skrepek, Nathanael
A Compactness Result for the div-curl System with Inhomogeneous Mixed Boundary Conditions for Bounded Lipschitz Domains and Some Applications
2021

4673.

Güttel, Stefan; Schweitzer, Marcel
A comparison of limited-memory Krylov methods for Stieltjes functions of Hermitian matrices
SIAM J. Matrix Anal. Appl., 42 (1) :83-107
2021

4672.

Güttel, Stefan; Schweitzer, Marcel
A comparison of limited-memory Krylov methods for Stieltjes functions of Hermitian matrices
SIAM J. Matrix Anal. Appl., 42 (1) :83-107
2021

4671.

Güttel, Stefan; Schweitzer, Marcel
A comparison of limited-memory Krylov methods for Stieltjes functions of Hermitian matrices
SIAM J. Matrix Anal. Appl., 42 (1) :83-107
2021

4670.

Edeko, Nikolai; Haase, Markus; Kreidler, Henrik
A Decomposition Theorem for Unitary Group Representations on Kaplansky-Hilbert Modules and the Furstenberg-Zimmer Structure Theorem
2021

4669.

Clevenhaus, Anna; Totzeck, Claudia; Ehrhardt, Matthias
A gradient descent algorithm for the Heston model
Preprint IMACM
2021
Herausgeber: Bergische Universität Wuppertal