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



1999

800.

Becker, Karl Heinz; Geiger, Harald; Schmidt, Frank; Wiesen, Peter
Kinetic investigation of NCO radicals reacting with selected hydrocarbons
Physical Chemistry Chemical Physics, 1 (23) :5305-5309
1999

799.

Becker, Karl Heinz; Geiger, Harald; Schmidt, Frank; Wiesen, Peter
Kinetic investigation of NCO radicals reacting with selected hydrocarbons
Physical Chemistry Chemical Physics, 1 (23) :5305-5309
1999

798.

Becker, Karl Heinz; Dinis, Carlos M.; Geiger, Harald; Wiesen, Peter
Kinetics of the reaction of OH with di-n-butoxymethane (DBM) in the range 298-710 K
Chemical Physics Letters, 300 (3-4) :460-464
1999

797.

Becker, Karl Heinz; Dinis, Carlos M.; Geiger, Harald; Wiesen, Peter
Kinetics of the reaction of OH with di-n-butoxymethane (DBM) in the range 298-710 K
Chemical Physics Letters, 300 (3-4) :460-464
1999
1998

796.

Schmidt, Sven; Benter, Thorsten; Schindler, Ralph N.
Photodissociation dynamcis of ClO radicals in the range (237
Chemical Physics Letters, 282 (3-4) :292-298
1998

795.

Becker, Karl Heinz; Kleffmann, Jörg; Negri, R. Martin; Wiesen, Peter
Solubility of nitrous acid (HONO) in ammonium sulfate solutions
Journal of the Chemical Society - Faraday Transactions, 94 (11) :1583-1586
1998
Herausgeber: The Royal Society of Chemistry

794.

Becker, Karl Heinz; Kleffmann, J{ö}rg; Negri, R. Martin; Wiesen, Peter
Solubility of nitrous acid (HONO) in ammonium sulfate solutions
Journal of the Chemical Society - Faraday Transactions, 94 (11) :1583-1586
1998
Herausgeber: The Royal Society of Chemistry

793.

Becker, Karl Heinz; Kleffmann, J{ö}rg; Negri, R. Martin; Wiesen, Peter
Solubility of nitrous acid (HONO) in ammonium sulfate solutions
Journal of the Chemical Society - Faraday Transactions, 94 (11) :1583-1586
1998
Herausgeber: The Royal Society of Chemistry

792.

Tausch, Michael W.
Sinn(e) der Fachdidaktik
{CHEMKON}, 5 (4) :173--173
1998
Herausgeber: Wiley

791.

Günther, Michael
Simulating digital circuits numerically--a charge-oriented ROW approach
Numerische Mathematik, 79 (2) :203--212
1998
Herausgeber: Springer-Verlag

790.

G\"unther, Michael
Simulating digital circuits numerically -- a charge-oriented {ROW} approach
Numer.~Math., 79 :203--212
1998

789.

Günther, Michael
Simulating digital circuits numerically - a charge-oriented ROW approach
Numerische Mathematik, 79 (2) :203–212
1998
Herausgeber: Springer New York

788.

[german] Tausch, Michael W.; Grolmuss, A.; Woock, M.
Vom Lichtquant zum Sehreiz
Praxis der Naturwissenschaften (Physik), 47 (5) :26
1998

787.

Schmidt, Sven; Benter, Thorsten; Schindler, Ralph N.
Photodissociation dynamcis of ClO radicals in the range (237
Chemical Physics Letters, 282 (3-4) :292-298
1998

786.

Shestakov, Oleg; Breidohr, R.; Demes, H.; Setzer, Klaus-Dieter; Fink, Ewald H.
Electronic States and Spectra of BiO
Journal of Molecular Spectroscopy, 190 (1) :28-77
1998
Herausgeber: Academic Press

785.

Shestakov, Oleg; Gielen, R.; Setzer, Klaus-Dieter; Fink, Ewald H.
Gas phase LIF study of the b1Σ+(b0+) ↔ X3Σ-(X10+,X21) transition of NI
Journal of Molecular Spectroscopy, 192 (1) :139-147
1998
Herausgeber: Academic Press

784.

Shestakov, Oleg; Gielen, R.; Setzer, Klaus-Dieter; Fink, Ewald H.
Gas phase LIF study of the b\(^{1}\)\(\Sigma\)\(^{+}\)(b0\(^{+}\)) ↔ X\(^{3}\)\(\Sigma\)\(^{-}\)(X\(_{1}\)0\(^{+}\),X\(_{2}\)1) transition of NI
Journal of Molecular Spectroscopy, 192 (1) :139-147
1998
Herausgeber: Academic Press

783.

Shestakov, Oleg; Gielen, R.; Setzer, Klaus-Dieter; Fink, Ewald H.
Gas phase LIF study of the b\(^{1}\)\(\Sigma\)\(^{+}\)(b0\(^{+}\)) ↔ X\(^{3}\)\(\Sigma\)\(^{-}\)(X\(_{1}\)0\(^{+}\),X\(_{2}\)1) transition of NI
Journal of Molecular Spectroscopy, 192 (1) :139-147
1998
Herausgeber: Academic Press

782.

Brasseur, G. P.; Cox, R. A.; Hauglustaine, D.; Isaksen, I.; Lelieveld, J.; Lister, D. H.; Sausen, R.; Schumann, Ulrich; Wahner, A.; Wiesen, Peter
European scientific assessment of the atmospheric effects of aircraft emissions
Atmospheric Environment, 32 (13) :2329-2418
1998

781.

Brasseur, G. P.; Cox, R. A.; Hauglustaine, D.; Isaksen, I.; Lelieveld, J.; Lister, D. H.; Sausen, R.; Schumann, Ulrich; Wahner, A.; Wiesen, Peter
European scientific assessment of the atmospheric effects of aircraft emissions
Atmospheric Environment, 32 (13) :2329-2418
1998

780.

Shestakov, Oleg; Breidohr, R.; Demes, H.; Setzer, Klaus-Dieter; Fink, Ewald H.
Electronic States and Spectra of BiO
Journal of Molecular Spectroscopy, 190 (1) :28-77
1998
Herausgeber: Academic Press

779.

Shestakov, Oleg; Breidohr, R.; Demes, H.; Setzer, Klaus-Dieter; Fink, Ewald H.
Electronic States and Spectra of BiO
Journal of Molecular Spectroscopy, 190 (1) :28-77
1998
Herausgeber: Academic Press

778.

Tausch, Michael W.; Grolmuss, A.; Piwek, B.
Echtfarben-Emissionsspektren EFES - Ein Beitrag zum Verständnis von Licht und Farbe
Praxis der Naturwissenschaften (Chemie), 47 (2) :10
1998

777.

Kleffmann, J{ö}rg; Becker, Karl Heinz; Wiesen, Peter
Heterogeneous NO\(_{2}\) conversion processes on acid surfaces
Atmospheric Environment, 32 (16) :2721-2729
1998

776.

Ehrhardt, Matthias
Discrete transparent boundary conditions for wide angle parabolic equations in underwater acoustics
Journal of Computational Physics, 145 (2) :611–638
1998
Herausgeber: Elsevier