Magnetics

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.

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

Efficiency of the time-integration for field devices in pulsed circuits (multirate, dynamic iteration)
DAE-index of the coupled system
Existence and Uniqueness of the solution

Cooperation

Herbert De Gersem, Katholieke Universiteit Leuven
Markus Clemens, Bergische Universität Wuppertal
Sascha Baumanns, Universität zu Köln

Former and ongoing projects

Publications

1994: 477.
Denk, Georg; Günther, M; Selting, Petra A
Efficient numerical methods in electronic circuit simulation
1994; 476.
Tausch, Michael W.; Wambach, H.
Entropie - was ist wissenschaftlich vertretbar und didaktisch sinnvoll?
Praxis der Naturwissenschaften (Chemie), 43 (2) :35
1994; 475.
Skov, H.; Benter, Thorsten; Schindler, Ralph N.; Hjorth, J.; Restelli, G.
Epoxide formation in the reactions of the nitrate radical with 2,3-dimethyl-2-butene, cis- and trans-2-butene and isoprene
Atmospheric Environment, 28 (9) :1583-1592
1994
DOI: 10.1016/1352-2310(94)90304-2; 474.
Skov, H.; Benter, Thorsten; Schindler, Ralph N.; Hjorth, J.; Restelli, G.
Epoxide formation in the reactions of the nitrate radical with 2,3-dimethyl-2-butene, cis- and trans-2-butene and isoprene
Atmospheric Environment, 28 (9) :1583-1592
1994
DOI: 10.1016/1352-2310(94)90304-2; 473.
Breidohr, R.; Setzer, Klaus-Dieter; Shestakov, Oleg; Fink, Ewald H.; Zyrnicki, W.
The a 3Σu+ (a1 1u) → X 1Σg+ (X 0g+) Transition of Bi2
Journal of Molecular Spectroscopy, 166 (2) :251-263
1994
Herausgeber: Academic Press
DOI: 10.1006/JMSP.1994.1191; 472.
Skov, H.; Benter, Thorsten; Schindler, Ralph N.; Hjorth, J.; Restelli, G.
Epoxide formation in the reactions of the nitrate radical with 2,3-dimethyl-2-butene, cis- and trans-2-butene and isoprene
Atmospheric Environment, 28 (9) :1583-1592
1994
DOI: 10.1016/1352-2310(94)90304-2; 471.
Kozin, Igor N.; Jensen, Per
Fourfold clusters of rovibrational energy levels for H\(_{2}\)S studied with a potential energy surface derived from experiment
Journal of Molecular Spectroscopy, 163 (2) :483-509
1994
Herausgeber: Academic Press
DOI: 10.1006/jmsp.1994.1041; 470.
Kozin, Igor N.; Jensen, Per
Fourfold clusters of rovibrational energy levels for H\(_{2}\)S studied with a potential energy surface derived from experiment
Journal of Molecular Spectroscopy, 163 (2) :483-509
1994
Herausgeber: Academic Press
DOI: 10.1006/jmsp.1994.1041; 469.
Kozin, Igor N.; Jensen, Per
Fourfold clusters of rovibrational energy levels for H2S studied with a potential energy surface derived from experiment
Journal of Molecular Spectroscopy, 163 (2) :483-509
1994
Herausgeber: Academic Press
DOI: 10.1006/jmsp.1994.1041; 468.
Breidohr, R.; Shestakov, Oleg; Fink, Ewald H.
The a \(^{3}\)\(\Sigma\)\(_{u}\)\(^{+}\)(a\(_{1}\) 1\(_{u}\)) → X \(^{1}\)\(\Sigma\)\(_{g}\)\(^{+}\) (X 0\(_{g}\)\(^{+}\)) transition of Sb\(_{2}\)
Chemical Physics Letters, 218 (1-2) :13-16
1994
DOI: 10.1016/0009-2614(93)E1449-Q
1993: 467.
Maten, E. J. W.; Huijben, A. J. M.
Vector extrapolation applied to a time cyclic heat problem
In Lewis, R. W., Editor, Numerical methods in thermal problemsBand8(2), Seite 983-994
In Lewis, R. W., Editor
Herausgeber: Pineridge Press Lmt, Swansea, UK
1993; 466.
Barclay, V. J.; Hamilton, I. P.; Jensen, Per
Vibrational levels for the lowest-lying triplet and singlet states of CH2 and NH2+
The Journal of Chemical Physics, 99 (12) :9709-9719
1993
DOI: 10.1063/1.465453; 465.
Kozin, Igor N.; Jensen, Per
Fourfold Clusters of Rovibrational Energy Levels in the Fundamental Vibrational States of H\(_{2}\)Se
Journal of molecular spectroscopy, 161 (1) :186-207
1993
Herausgeber: Academic Press
DOI: 10.1006/jmsp.1993.1226; 464.
Janssen, H. H. J. M.; Maten, E. J. W.; Houwelingen, D.
Simulation of coupled electromagnetic and heat dissipation problems
, IEE, Colloquium on Coupling Electromagnetic to Other FieldsBand1993 / 117, Seite 3/1-3/3
Herausgeber: Institute of Electrical and Electronics Engineers ({IEEE})
Mai 1993
DOI: 10.1109/20.312651; 463.
Shestakov, Oleg; Demes, H.; Fink, Ewald H.
Radiative lifetimes of the A 2Σ1/2+ and X2 2Π3/2 states of lead monohalides
Chemical Physics, 178 (1-3) :561-567
1993
DOI: 10.1016/0301-0104(93)85092-M; 462.
Shestakov, Oleg; Demes, H.; Fink, Ewald H.
Radiative lifetimes of the A \(^{2}\)\(\Sigma\)\(_{1/2}\)\(^{+}\) and X\(_{2}\) \(^{2}\)\(\Pi\)\(_{3/2}\) states of lead monohalides
Chemical Physics, 178 (1-3) :561-567
1993
DOI: 10.1016/0301-0104(93)85092-M; 461.
Shestakov, Oleg; Demes, H.; Fink, Ewald H.
Radiative lifetimes of the A \(^{2}\)\(\Sigma\)\(_{1/2}\)\(^{+}\) and X\(_{2}\) \(^{2}\)\(\Pi\)\(_{3/2}\) states of lead monohalides
Chemical Physics, 178 (1-3) :561-567
1993
DOI: 10.1016/0301-0104(93)85092-M; 460.
Günther, Michael; Rentrop, Peter
Partitioning and multirate strategies in latent electric circuits
1993; 459.
[german] Tausch, Michael W.; Kolkowski, M.; Weilert, K.
Ozon - der andere Sauerstoff
Praxis der Naturwissenschaften (Chemie), 42 (1) :26
1993; 458.
Günther, Michael; Rentrop, Peter
Multirate ROW methods and latency of electric circuits
Applied Numerical Mathematics, 13 (1-3) :83--102
1993
Herausgeber: North-Holland; 457.
G\"unther, Michael; Rentrop, P.
Multirate {ROW} methods and latency of electric circuits
Appl.~Numer.~Math., 13 :83--102
1993; 456.
Tausch, Michael W.; Wachtendonk, M.; Deissenberger, H.; Porth, H.-R.; G. Weißenhorn, R.
Lehrerband mit didaktischen Hinweisen und Lösungen zu den Aufgaben zu CHEMIE S II STOFF-FORMEL-UMWELT, Lehrbuch für Grund- und Leistungskurse
Herausgeber: C. C. Buchner, Bamberg
1993; 455.
Kozin, Igor N.; Jensen, Per
Fourfold Clusters of Rovibrational Energy Levels in the Fundamental Vibrational States of H2Se
Journal of molecular spectroscopy, 161 (1) :186-207
1993
Herausgeber: Academic Press
DOI: 10.1006/jmsp.1993.1226; 454.
Kozin, Igor N.; Jensen, Per
Fourfold Clusters of Rovibrational Energy Levels in the Fundamental Vibrational States of H\(_{2}\)Se
Journal of molecular spectroscopy, 161 (1) :186-207
1993
Herausgeber: Academic Press
DOI: 10.1006/jmsp.1993.1226; 453.
Maten, E. J. W.
Simulation of radiation heat transfer in television tubes
In R. W. Lewis, Editor, Numerical methods in thermal problemsBand8(1), Seite 831-842
In R. W. Lewis, Editor
Herausgeber: Pineridge Press Lmt, Swansea, UK
1993

Computational Magnetics

Research Questions

Cooperation

Former and ongoing projects

Publications

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