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

1989

267.

Fink, Ewald H.; Setzer, Klaus-Dieter; Ramsay, D. A.; Vervloet, M.
Near-infrared emission bands of TeH and TeD
Journal of Molecular Spectroscopy, 138 (1) :19-28
1989

DOI: 10.1016/0022-2852(89)90094-5

266.

Heilmann, Margareta
On simultaneous approximation by optimal algebraic polynomials
Results in Mathematics, 16 (1-2) :77-81
1989

DOI: 10.1007/BF03322645

265.

Heilmann, Margareta; Müller, Manfred
On simultaneous approximation by the method of Baskakov-Durrmeyer operators
Numerical Functional Analysis and Optimization, 10 (1-2) :127-138
1989

DOI: 10.1080/01630568908816295

264.

[german] Tausch, Michael W.; Wöhrle, D.
Photokatalyse
Praxis der Naturwissenschaften (Chemie), 38 :37
1989

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263.

Becker, Karl Heinz; Engelhardt, B.; Wiesen, Peter; Bayes, Kyle D.
Rate constants for CH(X\(^{2}\)\(\Pi\)) reactions at low total pressures
Chemical Physics Letters, 154 (4) :342-348
1989

DOI: 10.1016/0009-2614(89)85367-9

262.

Becker, Karl Heinz; Engelhardt, B.; Wiesen, Peter; Bayes, Kyle D.
Rate constants for CH(X\(^{2}\)\(\Pi\)) reactions at low total pressures
Chemical Physics Letters, 154 (4) :342-348
1989

DOI: 10.1016/0009-2614(89)85367-9

261.

Becker, Karl Heinz; Engelhardt, B.; Wiesen, Peter; Bayes, Kyle D.
Rate constants for CH(X2Π) reactions at low total pressures
Chemical Physics Letters, 154 (4) :342-348
1989

DOI: 10.1016/0009-2614(89)85367-9

260.

Fink, Ewald H.; Setzer, Klaus-Dieter; Ramsay, D. A.; Vervloet, M.; Xu, G. Z.
Rotational analysis of the 0-0 band of the b0\(^{+}\) → X\(_{1}\)0\(^{+}\) system of \(^{130}\)Te\(^{80}\)Se
Journal of Molecular Spectroscopy, 136 (1) :218-221
1989

DOI: 10.1016/0022-2852(89)90236-1

259.

Fink, Ewald H.; Setzer, Klaus-Dieter; Ramsay, D. A.; Vervloet, M.; Xu, G. Z.
Rotational analysis of the 0-0 band of the b0\(^{+}\) → X\(_{1}\)0\(^{+}\) system of \(^{130}\)Te\(^{80}\)Se
Journal of Molecular Spectroscopy, 136 (1) :218-221
1989

DOI: 10.1016/0022-2852(89)90236-1

258.

Fink, Ewald H.; Setzer, Klaus-Dieter; Ramsay, D. A.; Vervloet, M.; Xu, G. Z.
Rotational analysis of the 0-0 band of the b0+ → X10+ system of 130Te80Se
Journal of Molecular Spectroscopy, 136 (1) :218-221
1989

DOI: 10.1016/0022-2852(89)90236-1

257.

Tausch, Michael W.; Wachtendonk, M.
STOFF-FORMEL-UMWELT, BAND 1: CHEMISCHE GLEICHGEWICHTE - ELEKTROCHEMIE, Lehrbuch für die S II (Grund- und Leistungskurse), 172 Seiten
Herausgeber: C. C. Buchner, Bamberg
1989

256.

Wildt, J{ü}rgen; Fink, Ewald H.; Biggs, P.; Wayne, Richard P.
The collision-induced radiation of O\(_{2}\)(a\(^{1}\)\(\Delta\)\(_{g}\))
Chemical Physics, 139 (2-3) :401-407
1989

DOI: 10.1016/0301-0104(89)80152-1

255.

Wildt, J{ü}rgen; Fink, Ewald H.; Biggs, P.; Wayne, Richard P.
The collision-induced radiation of O\(_{2}\)(a\(^{1}\)\(\Delta\)\(_{g}\))
Chemical Physics, 139 (2-3) :401-407
1989

DOI: 10.1016/0301-0104(89)80152-1

254.

Wildt, Jürgen; Fink, Ewald H.; Biggs, P.; Wayne, Richard P.
The collision-induced radiation of O2(a1Δg)
Chemical Physics, 139 (2-3) :401-407
1989

DOI: 10.1016/0301-0104(89)80152-1

253.

Jensen, Per
The potential energy surface for the C\(_{3}\) molecule determined from experimental data. Evidence for a bent equilibrium structure
Collection of Czechoslovak Chemical Communications, 54 (5) :1209-1218
1989
Herausgeber: Institute of Organic Chemistry and Biochemistry AS CR, v.v.i.

DOI: 10.1135/cccc19891209

252.

Jensen, Per
The potential energy surface for the C\(_{3}\) molecule determined from experimental data. Evidence for a bent equilibrium structure
Collection of Czechoslovak Chemical Communications, 54 (5) :1209-1218
1989
Herausgeber: Institute of Organic Chemistry and Biochemistry AS CR, v.v.i.

DOI: 10.1135/cccc19891209

251.

Jensen, Per
The potential energy surface for the C3 molecule determined from experimental data. Evidence for a bent equilibrium structure
Collection of Czechoslovak Chemical Communications, 54 (5) :1209-1218
1989
Herausgeber: Institute of Organic Chemistry and Biochemistry AS CR, v.v.i.

DOI: 10.1135/cccc19891209

250.

Jensen, Per
The potential energy surface for the electronic ground state of the water molecule determined from experimental data using a variational approach
Journal of Molecular Spectroscopy, 133 (2) :438-460
1989

DOI: 10.1016/0022-2852(89)90203-8

249.

Jensen, Per
The potential energy surface for the electronic ground state of the water molecule determined from experimental data using a variational approach
Journal of Molecular Spectroscopy, 133 (2) :438-460
1989

DOI: 10.1016/0022-2852(89)90203-8

248.

Jensen, Per
The potential energy surface for the electronic ground state of the water molecule determined from experimental data using a variational approach
Journal of Molecular Spectroscopy, 133 (2) :438-460
1989

DOI: 10.1016/0022-2852(89)90203-8

247.

Schönfeld, J; Loennecken, I; Gückel, C
Unilateral pulsating tinnitus: paraganglioma of the glomus jugulare with predominantly vascular extension
Medizinische Klinik (Munich, Germany: 1983), 84 (9) :445--449
1989

246.

Heilmann, Margareta; Müller, Manfred
Weighted simultaneous L_p-approximation by the method of Baskakov-Durrmeyer operators
Approximation Theory VI, Proc. 6th Int. Symp., College Station/TX USA1989Band 1, Seite 331-332
1989

DOI: 10.1007/s10474-011-0135-x

1988

245.

Jensen, Per; Kraemer, Wolfgang P.
A comparison of perturbative and variational rotation-vibration energies calculated for HOC\(^{+}\) and C\(_{3}\) using the nonrigid bender and MORBID Hamiltonians
Journal of Molecular Spectroscopy, 129 (1) :172-185
1988

DOI: 10.1016/0022-2852(88)90268-8

244.

Jensen, Per; Kraemer, Wolfgang P.
A comparison of perturbative and variational rotation-vibration energies calculated for HOC\(^{+}\) and C\(_{3}\) using the nonrigid bender and MORBID Hamiltonians
Journal of Molecular Spectroscopy, 129 (1) :172-185
1988

DOI: 10.1016/0022-2852(88)90268-8

243.

Jensen, Per; Kraemer, Wolfgang P.
A comparison of perturbative and variational rotation-vibration energies calculated for HOC+ and C3 using the nonrigid bender and MORBID Hamiltonians
Journal of Molecular Spectroscopy, 129 (1) :172-185
1988

DOI: 10.1016/0022-2852(88)90268-8