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
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
- 1995
542.
G\"unther, Michael; Lehn, J.; Rentrop, P.; Rettig, S.; Simeon, B.
Wissenschaftliches Rechnen aus der Sicht der Mathematik
Thema Forschung 2/95, TH Darmstadt, 2 :26--35
1995- 1994
541.
Jensen, Per; Tashkun, Sergey A.; Tyuterev, Vladimir G.
A Refined Potential Energy Surface for the Electronic Ground State of the Water Molecule
Journal of Molecular Spectroscopy, 168 (2) :271-289
1994
Herausgeber: Academic Press540.
Jensen, Per; Tashkun, Sergey A.; Tyuterev, Vladimir G.
A Refined Potential Energy Surface for the Electronic Ground State of the Water Molecule
Journal of Molecular Spectroscopy, 168 (2) :271-289
1994
Herausgeber: Academic Press539.
Jensen, Per; Tashkun, Sergey A.; Tyuterev, Vladimir G.
A Refined Potential Energy Surface for the Electronic Ground State of the Water Molecule
Journal of Molecular Spectroscopy, 168 (2) :271-289
1994
Herausgeber: Academic Press538.
Polyansky, Oleg L.; Jensen, Per; Tennyson, Jonathan
A spectroscopically determined potential energy surface for the ground state of H\(_{2}\)\(^{16}\)O: A new level of accuracy
The Journal of Chemical Physics, 101 (9) :7651-7657
1994537.
Polyansky, Oleg L.; Jensen, Per; Tennyson, Jonathan
A spectroscopically determined potential energy surface for the ground state of H\(_{2}\)\(^{16}\)O: A new level of accuracy
The Journal of Chemical Physics, 101 (9) :7651-7657
1994536.
Polyansky, Oleg L.; Jensen, Per; Tennyson, Jonathan
A spectroscopically determined potential energy surface for the ground state of H216O: A new level of accuracy
The Journal of Chemical Physics, 101 (9) :7651-7657
1994535.
Kraemer, Wolfgang P.; Jensen, Per; Bunker, Philip R.
An ab initio calculation of the vibronic energies of the CH\(_{2}\)\(^{+}\) molecule
Canadian Journal of Physics, 72 (11-12) :871-878
1994
Herausgeber: NRC Research Press Ottawa, Canada534.
Kraemer, Wolfgang P.; Jensen, Per; Bunker, Philip R.
An ab initio calculation of the vibronic energies of the CH\(_{2}\)\(^{+}\) molecule
Canadian Journal of Physics, 72 (11-12) :871-878
1994
Herausgeber: NRC Research Press Ottawa, Canada533.
Kraemer, Wolfgang P.; Jensen, Per; Bunker, Philip R.
An ab initio calculation of the vibronic energies of the CH2+ molecule
Canadian Journal of Physics, 72 (11-12) :871-878
1994
Herausgeber: NRC Research Press Ottawa, Canada532.
Tausch, Michael W.
Atom, Molekül, Mol - eine Schulbuchsynopse über 80 Jahre
Praxis der Naturwissenschaften (Chemie), 43 (7) :32
1994531.
Günther, M.
Charge-oriented modelling of electric circuits and Rosenbrock-Wanner methods
Journal of Computing and Information, 4 :41–53
1994530.
Alml{ö}f, Jan; Jensen, Per; Northrup, F. J.; Rohlfing, Celeste Michael; Rohlfing, E. A.; Sears, T. J.
Comment on ''The \(\nu\)\(_{1}\) + \(\nu\)\(_{3}\) combination mode of C\(_{3}\) in Ar and Kr matrices: Evidence for a bent structure'' [J. Chem. Phys. 99, 7371 (1993)]
The Journal of Chemical Physics, 101 (6) :5413-5413
1994529.
Alml{ö}f, Jan; Jensen, Per; Northrup, F. J.; Rohlfing, Celeste Michael; Rohlfing, E. A.; Sears, T. J.
Comment on ''The \(\nu\)\(_{1}\) + \(\nu\)\(_{3}\) combination mode of C\(_{3}\) in Ar and Kr matrices: Evidence for a bent structure'' [J. Chem. Phys. 99, 7371 (1993)]
The Journal of Chemical Physics, 101 (6) :5413-5413
1994528.
Almlöf, Jan; Jensen, Per; Northrup, F. J.; Rohlfing, Celeste Michael; Rohlfing, E. A.; Sears, T. J.
Comment on "The ν1 + ν3 combination mode of C3 in Ar and Kr matrices: Evidence for a bent structure" [J. Chem. Phys. 99, 7371 (1993)]
The Journal of Chemical Physics, 101 (6) :5413-5413
1994527.
Denk, Georg; Selting, Petra A
Efficient numerical methods in electronic circuit simulation
Report TUM-M9413
1994
Herausgeber: Technische Universität München526.
Denk, Georg; Selting, Petra A
Efficient numerical methods in electronic circuit simulation
1994525.
Tausch, Michael W.; Wambach, H.
Entropie - was ist wissenschaftlich vertretbar und didaktisch sinnvoll?
Praxis der Naturwissenschaften (Chemie), 43 (2) :35
1994524.
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
1994523.
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
1994522.
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
1994521.
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 Press520.
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 Press519.
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 Press518.
Fink, Ewald H.; Setzer, Klaus-Dieter; Ramsay, D. A.; Zhu, Q.-S.
High-resolution study of the emission system of \(^{80}\)Se\(_{2}\) in the near infrared
Canadian Journal of Physics, 72 (11-12) :919-924
1994
Herausgeber: NRC Research Press Ottawa, Canada