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



1995

592.

Breidohr, R.; Shestakov, Oleg; Setzer, Klaus-Dieter; Fink, Ewald H.
High-Resolution Study of the a \(^{3}\)\(\Sigma\)\(^{+}\) (a\(_{1}\) 1) → X \(^{1}\)\(\Sigma\)\(^{+}\) (X 0\(^{+}\)) Transitions of BiP and BiAs
Journal of Molecular Spectroscopy, 172 (2) :369-377
1995
Herausgeber: Academic Press

591.

Breidohr, R.; Shestakov, Oleg; Setzer, Klaus-Dieter; Fink, Ewald H.
High-Resolution Study of the a 3Σ+ (a1 1) → X 1Σ+ (X 0+) Transitions of BiP and BiAs
Journal of Molecular Spectroscopy, 172 (2) :369-377
1995
Herausgeber: Academic Press

590.

Ziebarth, K.; Setzer, Klaus-Dieter; Fink, Ewald H.
High-Resolution Study of the X\(_{2}\) \(^{2}\)\(\Pi\)\(_{1/2}\) → X\(_{1}\) \(^{2}\)\(\Pi\)\(_{3/2}\) Fine-Structure Transitions of \(^{130}\)TeF and \(^{130}\)Te\(^{35}\)Cl
Journal of Molecular Spectroscopy, 173 (2) :488-498
1995
Herausgeber: Academic Press

589.

Ziebarth, K.; Setzer, Klaus-Dieter; Fink, Ewald H.
High-Resolution Study of the X\(_{2}\) \(^{2}\)\(\Pi\)\(_{1/2}\) → X\(_{1}\) \(^{2}\)\(\Pi\)\(_{3/2}\) Fine-Structure Transitions of \(^{130}\)TeF and \(^{130}\)Te\(^{35}\)Cl
Journal of Molecular Spectroscopy, 173 (2) :488-498
1995
Herausgeber: Academic Press

588.

Ziebarth, K.; Setzer, Klaus-Dieter; Fink, Ewald H.
High-Resolution Study of the X2 2Π1/2 → X1 2Π3/2 Fine-Structure Transitions of 130TeF and 130Te35Cl
Journal of Molecular Spectroscopy, 173 (2) :488-498
1995
Herausgeber: Academic Press

587.

Günther, Michael; Denk, Georg; Feldmann, Uwe
How models for MOS transistors reflect charge distribution effects
Preprint (1745)
1995
Herausgeber: Technische Hochschule Darmstadt

586.

Günther, Michael; Denk, Georg; Feldmann, Uwe
How models for MOS transistors reflect charge distribution effects
1995

585.

Günther, Michael; Denk, Georg; Feldmann, Uwe
Impact of modeling and integration scheme on simulation of MOS-circuits
In Breitenecker, F. and Husinsky, I., Editor, Eurosim'95 Simulation Congress. Proceedings of the 1995 EUROSIM Conference, EUROSIM '95, Seite 385–390
In Breitenecker, F. and Husinsky, I., Editor
Herausgeber: Elsevier
1995

584.

G\"unther, Michael; Denk, G.; Feldmann, U.
Impact of modeling and integration scheme on simulation of MOS-circuits
In F.~Breitenecker and I.~Husinsky., Editor, Eurosim'95 Simulation Congress, Seite 385--390
In F.~Breitenecker and I.~Husinsky., Editor
Herausgeber: Amsterdam, Elsevier
1995

583.

Jacob, Birgit; Drăgan, Vasile; Pritchard, Anthony J.
Infinite-dimensional time-varying systems with nonlinear output feedback
Integral Equations Operator Theory, 22 (4) :440--462
1995

582.

Becker, Karl Heinz; Kurtenbach, Ralf; Wiesen, Peter
Kinetic study of the NCO + C\(_{2}\)H\(_{4}\) reaction
Journal of Physical Chemistry, 99 (16) :5986-5991
1995

581.

Becker, Karl Heinz; Kurtenbach, Ralf; Wiesen, Peter
Kinetic study of the NCO + C\(_{2}\)H\(_{4}\) reaction
Journal of Physical Chemistry, 99 (16) :5986-5991
1995

580.

Becker, Karl Heinz; Kurtenbach, Ralf; Wiesen, Peter
Kinetic study of the NCO + C2H4 reaction
Journal of Physical Chemistry, 99 (16) :5986-5991
1995

579.

G\"unther, Michael
Ladungsorientierte {Rosenbrock}-{Wanner}-Methoden zur numerischen Simulation digitaler Schaltungen
Band 20(168) aus Fortschritt-Berichte VDI
Herausgeber: VDI-Verlag D\"usseldorf
1995

578.

Günther, M.
Ladungsorientierte Rosenbrock-Wanner-Methoden zur numerischen Simulation digitaler Schaltungen
1995

577.

Günther, Michael
Ladungsorientierte Rosenbrock-Wanner-Methoden zur numerischen Simulation digitaler Schaltungen
1995

576.

Becker, Karl Heinz; Kleffmann, Jörg; Kurtenbach, Ralf; Wiesen, Peter; Febo, Antonio; Gherardi, M.; Sparapani, R.
Line strength measurements of trans-HONO near 1255 cm\(^{-1}\) by tunable diode laser spectrometry
Geophysical Research Letters, 22 (18) :2485-2488
1995
Herausgeber: John Wiley \& Sons, Ltd

575.

Becker, Karl Heinz; Kleffmann, Jörg; Kurtenbach, Ralf; Wiesen, Peter; Febo, Antonio; Gherardi, M.; Sparapani, R.
Line strength measurements of trans-HONO near 1255 cm\(^{-1}\) by tunable diode laser spectrometry
Geophysical Research Letters, 22 (18) :2485-2488
1995
Herausgeber: John Wiley \& Sons, Ltd

574.

Becker, Karl Heinz; Kleffmann, Jörg; Kurtenbach, Ralf; Wiesen, Peter; Febo, Antonio; Gherardi, M.; Sparapani, R.
Line strength measurements of trans-HONO near 1255 cm-1 by tunable diode laser spectrometry
Geophysical Research Letters, 22 (18) :2485-2488
1995
Herausgeber: John Wiley & Sons, Ltd

573.

Jacob, Birgit
Linear quadratic optimal control of time-varying systems with indefinite costs on Hilbert spaces: the finite horizon problem
J. Math. Systems Estim. Control, 5 (1) :28
1995

572.

Benter, Thorsten; Liesner, M.; Sauerland, V.; Schindler, Ralph N.
Mass spectrometric in-situ determination of NO\(_{2}\) in gas mixtures by resonance enhanced multiphoton ionisation
Fresenius' Journal of Analytical Chemistry, 351 (6) :489-492
1995

571.

Benter, Thorsten; Liesner, M.; Sauerland, V.; Schindler, Ralph N.
Mass spectrometric in-situ determination of NO\(_{2}\) in gas mixtures by resonance enhanced multiphoton ionisation
Fresenius' Journal of Analytical Chemistry, 351 (6) :489-492
1995

570.

Benter, Thorsten; Liesner, M.; Sauerland, V.; Schindler, Ralph N.
Mass spectrometric in-situ determination of NO2 in gas mixtures by resonance enhanced multiphoton ionisation
Fresenius' Journal of Analytical Chemistry, 351 (6) :489-492
1995

569.

Wiesen, Peter; Kleffmann, Jörg; Kurtenbach, Ralf; Becker, Karl Heinz
Mechanistic study of the heterogeneous conversion of NO\(_{2}\) into HONO and N\(_{2}\)O on acid surfaces
Faraday Discussions, 100 (2) :121-127
1995

568.

Wiesen, Peter; Kleffmann, Jörg; Kurtenbach, Ralf; Becker, Karl Heinz
Mechanistic study of the heterogeneous conversion of NO\(_{2}\) into HONO and N\(_{2}\)O on acid surfaces
Faraday Discussions, 100 (2) :121-127
1995