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



2016

3517.

Tausch, Michael W.
Didaktisch integrativer Chemieunterricht - Kohärente Inhalte, Methoden und Medien
Praxis der Naturwissenschaften - Chemie in der Schule, 65 (5) :44
2016

3516.

Ehrhardt, Matthias
Discrete artificial boundary conditions for the linearized Korteweg-de Vries equation
Numerical Methods for Partial Differential Equations, 32 (5) :1455--1484
2016

3515.

Ehrhardt, Matthias
Discrete artificial boundary conditions for the linearized Korteweg-de Vries equation
Numerical Methods for Partial Differential Equations, 32 (5) :1455–1484
2016
Herausgeber: John Wiley & Sons

3514.

Ehrhardt, Matthias
Discrete artificial boundary conditions for the linearized Korteweg-de Vries equation
Numerical Methods for Partial Differential Equations, 32 (5) :1455–1484
2016
Herausgeber: John Wiley & Sons

3513.

Kleffmann, Jörg
Discussion on ''Field study of air purification paving elements containing TiO\(_{2}\)'' by Folli et al. (2015)
2016

3512.

Kleffmann, Jörg
Discussion on ''Field study of air purification paving elements containing TiO\(_{2}\)'' by Folli et al. (2015)
2016

3511.

Kleffmann, Jörg
Discussion on "Field study of air purification paving elements containing TiO2" by Folli et al. (2015)
2016

3510.

Wandelt, Michèle; Günther, Michael
Efficient numerical simulation of the Wilson Flow in lattice QCD
In Russo, Giovanni and Capasso, Vincenzo and Nicosia, Giuseppe and Romano, Vittorio, Editor, Progress in Industrial Mathematics at ECMI 2014ausMathematics in Industry, Seite 1065–1071
In Russo, Giovanni and Capasso, Vincenzo and Nicosia, Giuseppe and Romano, Vittorio, Editor
Herausgeber: Springer Cham
2016

3509.

Wandelt, Michèle; Günther, Michael
Efficient Numerical Simulation of the Wilson Flow in Lattice QCD
Progress in Industrial Mathematics at ECMI 2014 18, Seite 1065--1071
Springer International Publishing
2016

3508.

Wandelt, Michèle; Günther, Michael
Efficient numerical simulation of the Wilson Flow in lattice QCD
In Russo, Giovanni and Capasso, Vincenzo and Nicosia, Giuseppe and Romano, Vittorio, Editor, Progress in Industrial Mathematics at ECMI 2014ausMathematics in Industry, Seite 1065–1071
In Russo, Giovanni and Capasso, Vincenzo and Nicosia, Giuseppe and Romano, Vittorio, Editor
Herausgeber: Springer Cham
2016

3507.

Gonska, Heiner; Heilmann, Margareta; Raşa, Ioan
Eigenstructure of the genuine Beta operators of Lupaş and Mühlbach
Stud. Univ. Babes-Bolyai Math., 61 (3) :383-388
2016

3506.

Tausch, Michael W.; N. Rend{{\'o}}n-Enríquez, Ibeth; Scherf, Ullrich
Elektrochrome Fenster - Impulse für Jugend Forscht \& Co.
Praxis der Naturwissenschaften - Chemie in der Schule, 65 (8) :34
2016

3505.

N. Rend{{\'o}}n-Enríquez, Ibeth; Tausch, Michael W.; Scherf, Ullrich
Elektrochrome Fenster mit leitenden Polymeren
Chemie in unserer Zeit, 50 (6) :400--405
2016
Herausgeber: Wiley

3504.

Kurtenbach, Ralf; Vaupel, Kai; Kleffmann, Jörg; Klenk, Ulrich; Schmidt, Eberhard; Wiesen, Peter
Emissions of NO, NO\(_{2}\) and PM from inland shipping
Atmospheric Chemistry and Physics, 16 (22) :14285-14295
2016

3503.

Kurtenbach, Ralf; Vaupel, Kai; Kleffmann, Jörg; Klenk, Ulrich; Schmidt, Eberhard; Wiesen, Peter
Emissions of NO, NO\(_{2}\) and PM from inland shipping
Atmospheric Chemistry and Physics, 16 (22) :14285-14295
2016

3502.

Kurtenbach, Ralf; Vaupel, Kai; Kleffmann, Jörg; Klenk, Ulrich; Schmidt, Eberhard; Wiesen, Peter
Emissions of NO, NO2 and PM from inland shipping
Atmospheric Chemistry and Physics, 16 (22) :14285-14295
2016

3501.

Boufekran, Hajar
Enzymatische Delignifizierung vom Holz
2016

3500.

Frommer, Andreas; Schweitzer, Marcel
Error bounds and estimates for Krylov subspace approximations of Stieltjes matrix functions
BIT, 56 (3) :865-892
2016

3499.

Frommer, Andreas; Schweitzer, Marcel
Error bounds and estimates for Krylov subspace approximations of Stieltjes matrix functions
BIT, 56 (3) :865-892
2016

3498.

Frommer, Andreas; Schweitzer, Marcel
Error bounds and estimates for Krylov subspace approximations of Stieltjes matrix functions
BIT, 56 (3) :865-892
2016

3497.

Daners, Daniel; Glück, Jochen; Kennedy, James B.
Eventually and asymptotically positive semigroups on Banach lattices
J. Differential Equations, 261 (5) :2607--2649
2016

3496.

Daners, Daniel; Glück, Jochen; Kennedy, James B.
Eventually positive semigroups of linear operators
J. Math. Anal. Appl., 433 (2) :1561--1593
2016

3495.

Setzer, Klaus-Dieter; Fink, Ewald H.; Alekseyev, Aleksey B.; Liebermann, Heinz-Peter; Buenker, Robert J.
Experimental and theoretical study of the electronic states and spectra of NaAs
Journal of Molecular Spectroscopy, 320 :39-47
2016
Herausgeber: Academic Press

3494.

Setzer, Klaus-Dieter; Fink, Ewald H.; Alekseyev, Aleksey B.; Liebermann, Heinz-Peter; Buenker, Robert J.
Experimental and theoretical study of the electronic states and spectra of NaAs
Journal of Molecular Spectroscopy, 320 :39-47
2016
Herausgeber: Academic Press

3493.

Setzer, Klaus-Dieter; Fink, Ewald H.; Alekseyev, Aleksey B.; Liebermann, Heinz-Peter; Buenker, Robert J.
Experimental and theoretical study of the electronic states and spectra of NaAs
Journal of Molecular Spectroscopy, 320 :39-47
2016
Herausgeber: Academic Press