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

4293.

Heilmann, Margareta; Raşa, Ioan
Note on a proof for the representation of the kth order Kantorovich modification of linking Baskakov type operators
In Deo, Naokant and Gupta, Vijay and Acu, Ana Maria and Agrawal, P. N., Editor, Mathematical Analysis I: Approximation Theory , Seite 89–93
In Deo, Naokant and Gupta, Vijay and Acu, Ana Maria and Agrawal, P. N., Editor
Herausgeber: Springer Singapore
2020

4292.

Fatoorehchi, Hooman
Numerical and semi-numerical solutions of a modified Thévenin model with application to the dynamic analysis of electrochemical batteries
2020

4291.

Damm, Tobias; Jacob, Birgit
On coercivity and the frequency domain condition in indefinite LQ-control
Ann. Acad. Rom. Sci. Ser. Math. Appl., 12 (1-2) :553-563
2020

4290.

Schulze, Britta; Stiglmayr, Michael; Paquete, Luís; Fonseca, Carlos M.; Willems, David; Ruzika, Stefan
On the Rectangular Knapsack Problem Approximation of a Specific Quadratic Knapsack Problem
Mathematical Methods of Operations Research, 92 (1) :107-132
2020

4289.

Csomós, Petra; Ehrhardt, Matthias; Farkas, Bálint
Operator splitting for abstract cauchy problems with dynamical boundary condition
arXiv preprint arXiv:2004.13503
2020

4288.

Csomós, Petra; Ehrhardt, Matthias; Farkas, Bálint
Operator splitting for abstract Cauchy problems with dynamical boundary conditions
2020

4287.

Kruse, Thomas; Strack, Philipp
Optimal control of an epidemic through social distancing
Available at SSRN 3581295
2020

4286.

Ankirchner, Stefan; Fromm, Alexander; Kruse, Thomas; Popier, Alexandre
Optimal position targeting via decoupling fields
The Annals of Applied Probability, 30 (2) :644--672
2020
Herausgeber: Institute of Mathematical Statistics

4285.

Ankirchner, Stefan; Fromm, Alexander; Kruse, Thomas; Popier, Alexandre
Optimal position targeting via decoupling fields
The Annals of Applied Probability, 30 (2) :644–672
2020
Herausgeber: Institute of Mathematical Statistics

4284.

Beck, Christian; Hornung, Fabian; Hutzenthaler, Martin; Jentzen, Arnulf; Kruse, Thomas
Overcoming the curse of dimensionality in the numerical approximation of Allen--Cahn partial differential equations via truncated full-history recursive multilevel Picard approximations
Journal of Numerical Mathematics, 28 (4) :197--222
2020
Herausgeber: De Gruyter

4283.

Beck, Christian; Hornung, Fabian; Hutzenthaler, Martin; Jentzen, Arnulf; Kruse, Thomas
Overcoming the curse of dimensionality in the numerical approximation of Allen-Cahn partial differential equations via truncated full-history recursive multilevel Picard approximations
Journal of Numerical Mathematics, 28 (4) :197–222
2020
Herausgeber: De Gruyter

4282.

Hutzenthaler, Martin; Jentzen, Arnulf; Kruse, Thomas; Anh Nguyen, Tuan; Wurstemberger, Philippe
Overcoming the curse of dimensionality in the numerical approximation of semilinear parabolic partial differential equations
Proceedings of the Royal Society A, 476 (2244) :20190630
2020
Herausgeber: The Royal Society Publishing

4281.

Hutzenthaler, Martin; Jentzen, Arnulf; Kruse, Thomas; Anh Nguyen, Tuan; Wurstemberger, Philippe
Overcoming the curse of dimensionality in the numerical approximation of semilinear parabolic partial differential equations
Proceedings of the Royal Society A, 476 (2244) :20190630
2020
Herausgeber: The Royal Society Publishing

4280.

Bolten, M.; Friedhoff, S.; Hahne, J.; Schöps, S.
Parallel-in-time simulation of an electrical machine using MGRIT
Comput. Vis. Sci., 23 (1-4) :Paper No. 14, 14
2020

4279.

Bolten, Matthias; Friedhoff, S.; Hahne, J.; Schöps, S.
Parallel-in-time simulation of an electrical machine using MGRIT
Comput. Vis. Sci., 23 (1-4) :Paper No. 14, 14
2020

4278.

Bolten, M.; Friedhoff, S.; Hahne, J.; Schöps, S.
Parallel-in-time simulation of an electrical machine using MGRIT
Comput. Vis. Sci., 23 (1-4) :Paper No. 14, 14
2020

4277.

Schlachter, Louisa; Totzeck, Claudia
Parameter identification in uncertain scalar conservation laws discretized with the discontinuous stochastic Galerkin Scheme
Communications in Computational Physics, 28 (4) :1585-1608
2020

4276.

Brunnert, Rainer; Tausch, Michael W.; Bohrmann-Linde, Claudia
Paving the way for curriculum innovation through participatory action research in bilingual chemistry and bilingual biology lessons at German secondary schools: Results from a survey among teachers concerning their material demands
ARISE, 1 (3) :17--23
2020

4275.

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

4274.

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

4273.

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

4272.

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

4271.

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

4270.

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

4269.

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