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



2014

2867.


Multi-Band Effective Mass Approximations: Advanced Mathematical Models and Numerical Techniques
In Ehrhardt, Matthias and Koprucki, Thomas, Editor aus Lecture Notes in Computational Science and Engineering
Herausgeber: Springer Cham
2014

ISBN: 978-3-319-01426-5

2866.

Wallington, T. J.; Wiesen, Peter
N\(_{2}\)O emissions from global transportation
Atmospheric Environment, 94 :258-263
2014
Herausgeber: Pergamon

2865.

Wallington, T. J.; Wiesen, Peter
N\(_{2}\)O emissions from global transportation
Atmospheric Environment, 94 :258-263
2014
Herausgeber: Pergamon

2864.

Wallington, T. J.; Wiesen, Peter
N2O emissions from global transportation
Atmospheric Environment, 94 :258-263
2014
Herausgeber: Pergamon

2863.

Maten, E Jan W; Günther, Michael; Putek, Piotr; Benner, Peter; Feng, Lihong; Schneider, Judith; Brachtendorf, Hans-Georg; Bittner, Kai; Deleu, Frederik; Wieers, Aarnout; others
Nanocops: Nanoelectronic coupled problem solutions
2014
Herausgeber: Mathematics and Industry

2862.

Setzer, Klaus-Dieter; Fink, Ewald H.
Near-infrared emission spectra of TeS, TeSe and Te\(_{2}\)
Journal of Molecular Spectroscopy, 304 :28-36
2014
Herausgeber: Academic Press

2861.

Setzer, Klaus-Dieter; Fink, Ewald H.
Near-infrared emission spectra of TeS, TeSe and Te\(_{2}\)
Journal of Molecular Spectroscopy, 304 :28-36
2014
Herausgeber: Academic Press

2860.

Setzer, Klaus-Dieter; Fink, Ewald H.
Near-infrared emission spectra of TeS, TeSe and Te2
Journal of Molecular Spectroscopy, 304 :28-36
2014
Herausgeber: Academic Press

2859.

Putek, Piotr; PAPLICKI, Piotr; Pulch, Roland; Maten, E. Jan W.; Günther, Michael; Palka, Ryszard
Nonlinear multiobjective topology optimization and multiphysics analysis of a permanent-magnet excited synchronous machine
Optimization and Inverse Problems in Electromagnetism OIPE-2014 Book of Digests, Seite 107–108
Herausgeber: TU Delf
2014

2858.

Putek, Piotr; PAPLICKI, Piotr; Pulch, Roland; Maten, E. Jan W.; Günther, Michael; Palka, Ryszard
Nonlinear multiobjective topology optimization and multiphysics analysis of a permanent-magnet excited synchronous machine
Optimization and Inverse Problems in Electromagnetism OIPE-2014 Book of Digests, Seite 107–108
Herausgeber: TU Delf
2014

2857.

Ehrhardt, M.
Nonstandard Finite Difference Schemes for the {Black-Scholes} Equation
In A. Gumel, Editor, Mathematics of Continuous and Discrete Dynamical SystemsBand618, Seite 217--228
In A. Gumel, Editor
Herausgeber: AMS (Contemporary Mathematics)
2014

2856.

Ehrhardt, Matthias
Nonstandard Finite Difference Schemes for the Black--Scholes Equation
Mathematics of Continuous and Discrete Dynamical Systems: Contemporary Mathematics, 618 :217
2014
Herausgeber: American Mathematical Soc.

2855.

Ehrhardt, Matthias
Nonstandard finite difference schemes for the Black-Scholes equation
Contemporary Mathematics, 618 :217–227
2014
Herausgeber: American Mathematical Society

2854.

Ehrhardt, Matthias
Nonstandard finite difference schemes for the Black-Scholes equation
Contemporary Mathematics, 618 :217–227
2014
Herausgeber: American Mathematical Society

2853.

Ehrhardt, Matthias
Numerical analysis of nonlinear European option pricing problem in illiquid markets
2014

2852.

Ehrhardt, Matthias
Numerical analysis of nonlinear European option pricing problem in illiquid markets
Preprint IMACM
2014
Herausgeber: Bergische Universität Wuppertal

2851.

Ehrhardt, Matthias
Numerical analysis of nonlinear European option pricing problem in illiquid markets
Preprint IMACM
2014
Herausgeber: Bergische Universität Wuppertal

2850.

Ehrhardt, Matthias; Sánchez, Lucas Jódar; Villanueva Micó, Rafael Jacinto
Numerical methods and mathematical modelling in biology, medicine and social sciences
2014

2849.

Ehrhardt, Matthias; Sánchez, Lucas Jódar; Villanueva Micó, Rafael Jacinto
Numerical methods and mathematical modelling in biology, medicine and social sciences
International Journal of Computer Mathematics, 91 (2) :176–178
2014
Herausgeber: Taylor & Francis

2848.

Ehrhardt, Matthias; Sánchez, Lucas Jódar; Villanueva Micó, Rafael Jacinto
Numerical methods and mathematical modelling in biology, medicine and social sciences
International Journal of Computer Mathematics, 91 (2) :176–178
2014
Herausgeber: Taylor & Francis

2847.

Bartel, A.; Brunk, M.; Sch\"ops, S.
On the convergence rate of dynamic iteration for coupled problems with multiple subsystem
J. Comp. Appl. Math., 262 :14--24
2014

2846.

Bartel, Andreas; Brunk, Markus; Schöps, Sebastian
On the convergence rate of dynamic iteration for coupled problems with multiple subsystems
Journal of Computational and Applied Mathematics, 262 :14–24
2014
Herausgeber: North-Holland

2845.

Bartel, Andreas; Brunk, Markus; Schöps, Sebastian
On the convergence rate of dynamic iteration for coupled problems with multiple subsystems
Journal of Computational and Applied Mathematics, 262 :14--24
2014
Herausgeber: North-Holland

2844.

Stiglmayr, Michael; Figueira, José Rui; Klamroth, Kathrin
On the multicriteria allocation problem
Annals of Operations Research, 222 (1) :535-549
2014
Herausgeber: Springer

2843.

Farkas, B{\'a}lint; Pintz, J{\'a}nos; Révész, Szil{\'a}rd
On the optimal weight function in the {G}oldston-{P}intz-{Y}\textbackslashi ld\textbackslashi r\textbackslashi m method for finding small gaps between consecutive primes
Number theory, analysis, and combinatorics
Seite 75--104
Herausgeber: De Gruyter, Berlin, https://arxiv.org/abs/1306.2133
2014
75--104