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



2019

3992.

Ankirchner, Stefan; Kruse, Thomas; Urusov, Mikhail
Wasserstein convergence rates for random bit approximations of continuous Markov processes
Journal of Mathematical Analysis and Applications, 493 (2) :124543
2019
Herausgeber: Academic Press

3991.

Jacob, Birgit; Wegner, Sven-Ake
Well-posedness of a class of hyperbolic partial differential equations on the semi-axis
J. Evol. Equ., 19 (4) :1111--1147
2019

3990.

Jacob, Birgit; Kaiser, Julia T.
Well-posedness of systems of 1-{D} hyperbolic partial differential equations
J. Evol. Equ., 19 (1) :91--109
2019

3989.

Jacob, Birgit; Kaiser, Julia T.
Well-posedness of systems of 1-D hyperbolic partial differential equations
J. Evol. Equ., 19 (1) :91--109
2019

3988.

Ehrhardt, Matthias
Wide-angle mode parabolic equation with transparent boundary conditions and its applications in shallow water acoustics
2019 Days on Diffraction (DD), Seite 221–225
IEEE
Herausgeber: IEEE
2019

3987.

Ehrhardt, Matthias
Wide-angle mode parabolic equation with transparent boundary conditions and its applications in shallow water acoustics
2019 Days on Diffraction (DD), Seite 221--225
IEEE
2019

3986.

Ehrhardt, Matthias
Wide-angle mode parabolic equation with transparent boundary conditions and its applications in shallow water acoustics
2019 Days on Diffraction (DD), Seite 221–225
IEEE
Herausgeber: IEEE
2019

3985.

Cuny, Christophe; Eisner, Tanja; Farkas, Bálint
Wiener's lemma along primes and other subsequences
Advances in Mathematics, 347 :340 - 383
2019

3984.

Jacob, Birgit; Morris, Kirsten A.; Zwart, Hans
Zero dynamics for networks of waves
Automatica J. IFAC, 103 :310--321
2019
2018

3983.

Sharma, M. K.; Göstl, Robert; Frijns, A. J. H.; Wieringa, F. P.; Kooman, J. P.; Sijbesma, R. P.; Smeulders, D. M. J.
A Fluorescent Micro-Optofluidic Sensor for In-Line Ion Selective Electrolyte Monitoring
IEEE Sensors Journal, 18 (10) :3946--3951
Mai 2018
ISSN: 1530-437X

3982.


[1,2]-Migration Reactions Catalyzed by Gold Complexes and their Applications in Total Synthesis
Israel Journal of Chemistry, 58 (5) :596–607
2018
ISSN: 1869-5868

3981.

Jacob, Birgit; Partington, Jonathan R.; Pott, Sandra; Wynn, Andrew
{\(\beta\)}-admissibility of observation operators for hypercontractive semigroups
J. Evol. Equ., 18 (1) :153--170
2018

3980.

Jacob, Birgit; Partington, Jonathan R.; Pott, Sandra; Wynn, Andrew
β-admissibility of observation operators for hypercontractive semigroups
J. Evol. Equ., 18 (1) :153--170
2018

3979.

Daners, Daniel; Glück, Jochen
A criterion for the uniform eventual positivity of operator semigroups
Integral Equations Operator Theory, 90 (4) :Paper No. 46, 19
2018

3978.

Farkas, Bálint; Nagy, Béla; Révész, Szilárd Gy.
A minimax problem for sums of translates on the torus
Transactions of the London Mathematical Society, 5 (1) :1-46
2018

3977.

Kossaczky, Igor; Ehrhardt, Matthias; Günther, Michael
A new convergent explicit tree-grid method for HJB equations in one space dimension
Numerical Mathematics: Theory, Methods and Applications, 11 (1) :1–29
2018
Herausgeber: Global Science Press

3976.

Ehrhardt, Matthias; Günther, Michael
A new convergent explicit Tree-Grid method for HJB equations in one space dimension
Preprint, 17 (06)
2018

3975.

Kossaczky, Igor; Ehrhardt, Matthias; Günther, Michael
A new convergent explicit tree-grid method for HJB equations in one space dimension
Numerical Mathematics: Theory, Methods and Applications, 11 (1) :1–29
2018
Herausgeber: Global Science Press

3974.

Kossaczky, Igor; Ehrhardt, Matthias; Günther, Michael
A new convergent explicit tree-grid method for HJB equations in one space dimension
Numerical Mathematics: Theory, Methods and Applications, 11 (1) :1–29
2018
Herausgeber: Global Science Press

3973.

Heilmann, Margareta; Raşa, Ioan
A nice representation for a link between Baskakov-and Szász–Mirakjan–Durrmeyer operators and their kantorovich variants
Results in Mathematics, 74 (1) :9
2018

3972.

Glück, Jochen
A note on lattice ordered $C^*$-algebras and Perron-Frobenius theory
Math. Nachr., 291 (11-12) :1727--1732
2018

3971.

Bartel, Andreas; Ehrhardt, Matthias
A numerical tool for the study of the hydrodynamic recovery of the lattice Boltzmann Method
Computers & Fluids, 172 :241–250
2018
Herausgeber: Pergamon

3970.

Bartel, Andreas; Ehrhardt, Matthias
A numerical tool for the study of the hydrodynamic recovery of the Lattice Boltzmann Method
Computers & Fluids, 172 :241--250
2018
Herausgeber: Pergamon

3969.

Bartel, Andreas; Ehrhardt, Matthias
A numerical tool for the study of the hydrodynamic recovery of the lattice Boltzmann Method
Computers & Fluids, 172 :241–250
2018
Herausgeber: Pergamon

3968.

Harbrecht, Helmut; Zaspel, Peter
A scalable H-matrix approach for the solution of boundary integral equations on multi-GPU clusters
2018