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

2003

1159.

Setzer, Klaus-Dieter; Dorn, A.; Lorenz, Matthias; Fink, Ewald H.
The a1Δg(a2g) → X3Σg-(X21g) transition of Se2
Journal of Molecular Spectroscopy, 221 (1) :13-18
2003
Herausgeber: Academic Press

DOI: 10.1016/S0022-2852(03)00199-1

1158.

Geiger, Harald; Barnes, Ian; Bejan, Iustinian; Benter, Thorsten; Spittler, M.
The tropospheric degradation of isoprene: an updated module for the regional atmospheric chemistry mechanism
Atmospheric Environment, 37 (11) :1503-1519
2003

DOI: 10.1016/S1352-2310(02)01047-6

1157.

Geiger, Harald; Barnes, Ian; Bejan, Iustinian; Benter, Thorsten; Spittler, M.
The tropospheric degradation of isoprene: an updated module for the regional atmospheric chemistry mechanism
Atmospheric Environment, 37 (11) :1503-1519
2003

DOI: 10.1016/S1352-2310(02)01047-6

1156.

Geiger, Harald; Barnes, Ian; Bejan, Iustinian; Benter, Thorsten; Spittler, M.
The tropospheric degradation of isoprene: an updated module for the regional atmospheric chemistry mechanism
Atmospheric Environment, 37 (11) :1503-1519
2003

DOI: 10.1016/S1352-2310(02)01047-6

1155.

Kirsch, Stefan; Bach, Thorsten
Total Synthesis of (+)-Wailupemycin B
Angewandte Chemie International Edition, 42 (38) :4685–4687
2003
ISSN: 1433-7851, 1521-3773

DOI: 10.1002/anie.200351455

1154.

Jensen, Per; Kraemer, Wolfgang P.; Bunker, Philip R.
Transition moments and NH\(_{2}\) cometary spectra
Molecular Physics, 101 (4-5) :613-622
2003
Herausgeber: Taylor \& Francis Group

DOI: 10.1080/0026897021000021840

1153.

Jensen, Per; Kraemer, Wolfgang P.; Bunker, Philip R.
Transition moments and NH\(_{2}\) cometary spectra
Molecular Physics, 101 (4-5) :613-622
2003
Herausgeber: Taylor \& Francis Group

DOI: 10.1080/0026897021000021840

1152.

Jensen, Per; Kraemer, Wolfgang P.; Bunker, Philip R.
Transition moments and NH2 cometary spectra
Molecular Physics, 101 (4-5) :613-622
2003
Herausgeber: Taylor & Francis Group

DOI: 10.1080/0026897021000021840

1151.

Klamroth, Kathrin; Tind, Jørgen; Wiecek, Margaret M.
Unbiased approximation in multicriteria optimization
Mathematical Methods of Operations Research, 56 :413-437
2003

DOI: 10.1007/s001860200217

1150.

Tausch, Michael W.; Wachtendonk, M.
UNTERRICHTSPRAXIS S II, Band 2 ''Elektrochemische Stromquellen''
Herausgeber: Aulis Verlag Deubner, Köln
2003

1149.

Tausch, Michael W.
Wasserstoff - der Spitzenreiter unter den Elementen
Praxis der Naturwissenschaften - Chemie in der Schule, 53 (3) :1
2003

1148.

Zwart, Hans; Jacob, Birgit; Staffans, Olof
Weak admissibility does not imply admissibility for analytic semigroups
, Band 48
Seite 341--350
2003
341--350

DOI: 10.1016/S0167-6911(02)00277-3

2002

1147.

Lin, C.; Heijmen, T.; Maten, J.; Kole, M.
ADAPT: Design assistance for iterative analogue synthesis
In W. Anheier and R. Laur and H. Gräb, Editor, Analog 2002 - Entwicklung von Analogschaltungen mit CAE-Methoden, BremenBand38ausGMM-Fachbericht, Seite 195-200
In W. Anheier and R. Laur and H. Gräb, Editor
Herausgeber: VDE Verlag GMBH, Berlin
Mai 2002

1146.

Klamroth, Kathrin; Wiecek, Margaret M.
A bi-objective median location problem with a line barrier
Operations Research, 50 :670-679
2002

DOI: 10.1287/opre.50.4.670.2857

1145.

Jacob, Birgit; Leblond, Juliette; Marmorat, Jean-Paul; Partington, Jonathan R.
A constrained approximation problem arising in parameter identification
, Band 351/352
Seite 487--500
2002
487--500

DOI: 10.1016/S0024-3795(01)00445-1

1144.

Mannschreck, K.; B{ä}chmann, K.; Becker, Karl Heinz; Heil, Th.; Kurtenbach, Ralf; Memmesheimer, M.; Mohnen, V.; Obermeier, A.; Poppe, Dirk; Steinbrecher, R.; Schmitz, Th.; Volz-Thomas, A.; Zabel, Friedhelm
A database for volatile organic compounds
Journal of Atmospheric Chemistry, 42 (1-3) :281-286
2002

DOI: 10.1023/A:1015708211775

1143.

Mannschreck, K.; B{ä}chmann, K.; Becker, Karl Heinz; Heil, Th.; Kurtenbach, Ralf; Memmesheimer, M.; Mohnen, V.; Obermeier, A.; Poppe, Dirk; Steinbrecher, R.; Schmitz, Th.; Volz-Thomas, A.; Zabel, Friedhelm
A database for volatile organic compounds
Journal of Atmospheric Chemistry, 42 (1-3) :281-286
2002

DOI: 10.1023/A:1015708211775

1142.

Mannschreck, K.; Bächmann, K.; Becker, Karl Heinz; Heil, Th.; Kurtenbach, Ralf; Memmesheimer, M.; Mohnen, V.; Obermeier, A.; Poppe, Dirk; Steinbrecher, R.; Schmitz, Th.; Volz-Thomas, A.; Zabel, Friedhelm
A database for volatile organic compounds
Journal of Atmospheric Chemistry, 42 (1-3) :281-286
2002

DOI: 10.1023/A:1015708211775

1141.

Pulch, R.; Günther, M.
A method of characteristics for solving multirate partial differential equations in radio frequency application
Applied Numerical Mathematics, 42 (1) :397–409
2002
Herausgeber: Elsevier

DOI: 10.1016/S0168-9274(01)00163-5

1140.

Pulch, Roland; Günther, Michael
A method of characteristics for solving multirate partial differential equations in radio frequency application
Applied numerical mathematics, 42 (1-3) :397--409
2002
Herausgeber: North-Holland

1139.

Bartel, Andreas; Günther, Michael
A multirate W-method for electrical networks in state-space formulation
Journal of Computational and Applied Mathematics, 147 (2) :411–425
2002
Herausgeber: Elsevier

DOI: 10.1016/S0377-0427(02)00476-4

1138.

Bartel, A.; G\"unther, Michael
A multirate W-method for electrical networks in state-space formulation
Comp.~Appl.~Math., 147 (2) :411--425
2002

1137.

Odaka, Tina Erica; Hirano, Tsuneo; Jensen, Per
A theoretical study of A\verb=~=\(^{2}\)\(\Pi\) MgCN
Journal of Molecular Spectroscopy, 216 (2) :379-396
2002

DOI: 10.1006/jmsp.2002.8633

1136.

Odaka, Tina Erica; Hirano, Tsuneo; Jensen, Per
A theoretical study of A\verb=~=\(^{2}\)\(\Pi\) MgCN
Journal of Molecular Spectroscopy, 216 (2) :379-396
2002

DOI: 10.1006/jmsp.2002.8633

1135.

Jensen, Per; Wesolowski, Steven S.; Brinkmann, Nicole R.; Richardson, Nancy A.; Yamaguchi, Yukio; Schaefer, Henry F.; Bunker, Philip R.
A Theoretical Study of a\verb=~=\(^{4}\)A\(_{2}\) CH\(_{2}\)\(^{+}\)
Journal of Molecular Spectroscopy, 211 (2) :254-261
2002

DOI: 10.1006/jmsp.2001.8503