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



2020

4241.

Berdysheva, Elena; Heilmann, Margareta; Hennings, Katharina
Pointwise convergence of the Bernstein-Durrmeyer operator with respect to a collection of measures
Journal of Approximation Theory, 251, Article 105339
2020

4240.

Arendt, Wolfgang; Glück, Jochen
Positive irreducible semigroups and their long-time behaviour
Philos. Trans. Roy. Soc. A, 378 (2185) :20190611, 17
2020

4239.

Clevenhaus, Anna; Ehrhardt, Matthias; Günther, Michael; Ševčovič, Daniel
Pricing {American} Options with a Non-Constant Penalty Parameter
J. Risk Fin. Managem., 13 (6) :124
Juni 2020

4238.

Clevenhaus, Anna; Ehrhardt, Matthias; Günther, Michael; Ševčovič, Daniel
Pricing American options with a non-constant penalty parameter
Journal of Risk and Financial Management, 13 (6) :124
2020
Herausgeber: MDPI

4237.

Clevenhaus, Anna; Ehrhardt, Matthias; Günther, Michael; Ševčovič, Daniel
Pricing American options with a non-constant penalty parameter
Journal of Risk and Financial Management, 13 (6) :124
2020
Herausgeber: MDPI

4236.

Clevenhaus, Anna; Ehrhardt, Matthias; Günther, Michael; Ševčovič, Daniel
Pricing American options with a non-constant penalty parameter
Journal of Risk and Financial Management, 13 (6) :124
2020
Herausgeber: MDPI

4235.

Clevenhaus, Anna; Ehrhardt, Matthias; Günther, Michael; Ševčovič, Daniel
Pricing American options with a non-constant penalty parameter
Journal of Risk and Financial Management, 13 (6) :124
2020
Herausgeber: MDPI

4234.

Schl\"uter, Felix; Gottowik, Marvin; Huege, Tim; Rautenberg, Julian
Refractive displacement of the radio-emission footprint of inclined air showers simulated with CoREAS
Eur. Phys. J. C, 80 (7) :643
2020

4233.

Farkas, Bálint; Kreidler, Henrik
Relative compactness of orbits and geometry of Banach spaces
J. Math. Anal. Appl
2020

4232.

Jacob, Birgit; Schwenninger, Felix; Vorberg, Lukas
Remarks on input-to-state stability of collocated systems with saturated feedback
Mathematics of Control, Signals, and Systems, 32 (3) :293-307
2020

4231.

Mittendorf, Fabia; Mohr, Fabian
Ring Expansion of 2-Azido-2-phenyl-indan-1,3-dione for the Generation of Heterocyclic Scaffolds
The Journal of Organic Chemistry, 85 (19) :12760–12769
2020
ISSN: 0022-3263, 1520-6904

4230.

Tong, My Linh; Leusch, Lena Theresa
Rubazonic Acids and Their Synthesis
The Journal of Organic Chemistry, 85 (9) :6008–6016
2020
ISSN: 0022-3263, 1520-6904

4229.

Putek, Piotr; Bartel, Andreas; Günther, Michael
Shape Optimization of a {PM} Synchronous Machine Under Probabilistic Constraints
Scientific Computing in Electrical Engineering: SCEE 2018, Taormina, Italy, September 2018 12, Seite 243--253
Springer International Publishing
2020

4228.

Putek, Piotr; Bartel, Andreas; Günther, Michael
Shape optimization of a PM synchronous machine under probabilistic constraints
In Nicosia, Giuseppe and Romano, Vittorio, Editor, Scientific Computing in Electrical Engineering: SCEE 2018, Taormina, Italy, September 2018ausMathematics in Industry, Seite 243–253
In Nicosia, Giuseppe and Romano, Vittorio, Editor
Herausgeber: Springer Cham
2020

4227.

Putek, Piotr; Bartel, Andreas; Günther, Michael
Shape optimization of a PM synchronous machine under probabilistic constraints
In Nicosia, Giuseppe and Romano, Vittorio, Editor, Scientific Computing in Electrical Engineering: SCEE 2018, Taormina, Italy, September 2018ausMathematics in Industry, Seite 243–253
In Nicosia, Giuseppe and Romano, Vittorio, Editor
Herausgeber: Springer Cham
2020

4226.

Putek, Piotr; Bartel, Andreas; Günther, Michael
Shape Optimization of a PM Synchronous Machine Under Probabilistic Constraints
Scientific Computing in Electrical Engineering: SCEE 2018, Taormina, Italy, September 2018 12, Seite 243--253
Springer International Publishing
2020

4225.

Pinnau, Rene; Totzeck, Claudia
Space mapping-based receding horizon control for stochastic interacting particle systems: dogs herding sheep
Journal of Mathematics in Industry, 10 (11)
2020

4224.

Durastante, Fabio; Furci, Isabella
Spectral analysis of saddle-point matrices from optimization problems with elliptic PDE constraints
Electron. J. Linear Algebra, 36 :773-798
2020

4223.

Durastante, Fabio; Furci, Isabella
Spectral analysis of saddle-point matrices from optimization problems with elliptic PDE constraints
Electron. J. Linear Algebra, 36 :773-798
2020

4222.

Durastante, Fabio; Furci, Isabella
Spectral analysis of saddle-point matrices from optimization problems with elliptic PDE constraints
Electron. J. Linear Algebra, 36 :773-798
2020

4221.

Glück, Jochen
Spectral gaps for hyperbounded operators
Adv. Math., 362 :106958, 24
2020

4220.

[german] Meuter, Nico; Spinnen, Sebastian; Yurdanur, Yasemin; Tausch, Michael W.
Spiropyran - ein didaktisches Multitalent - Experimentelle Erschließung chemischer Basiskonzepte mit dem molekularen Schalter Spiropyran/Merocyanin
CHEMKON, 27 (4) :169--178
2020

4219.

Jacob, Birgit; Möller, Sebastian; Wyss, Christian
Stability radius for infinite-dimensional interconnected systems
Systems Control Lett., 138 :Article ID 104662, 8 p.
2020

4218.

Ballaschk, Frederic; Özkaya, Yasemin
Stereocontrolled Synthesis of Harzialactone A and Its Three Stereoisomers by Use of Standardized Polyketide Building Blocks
European Journal of Organic Chemistry, 2020 (38) :6078–6080
2020
ISSN: 1434-193X, 1099-0690

4217.

Arendt, Wolfgang; ter Elst, Antonius F. M.; Glück, Jochen
Strict positivity for the principal eigenfunction of elliptic operators with various boundary conditions
Adv. Nonlinear Stud., 20 (3) :633--650
2020