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

1993

429.

Kozin, Igor N.; Klee, Stefan; Jensen, Per; Polyansky, Oleg L.; Pavlichenkov, I. M.
The Far-Infrared Fourier Transform Spectrum of H2Se
Journal of Molecular Spectroscopy, 158 (2) :409-422
1993
Herausgeber: Academic Press

DOI: 10.1006/JMSP.1993.1085

428.

Biggs, P.; Canosa-Mas, Carlos E.; Monks, P. S.; Wayne, Richard P.; Benter, Thorsten; Schindler, Ralph N.
The kinetics of the nitrate radical self-reaction
International Journal of Chemical Kinetics, 25 (10) :805-817
1993

DOI: 10.1002/kin.550251002

427.

Biggs, P.; Canosa-Mas, Carlos E.; Monks, P. S.; Wayne, Richard P.; Benter, Thorsten; Schindler, Ralph N.
The kinetics of the nitrate radical self-reaction
International Journal of Chemical Kinetics, 25 (10) :805-817
1993

DOI: 10.1002/kin.550251002

426.

Biggs, P.; Canosa-Mas, Carlos E.; Monks, P. S.; Wayne, Richard P.; Benter, Thorsten; Schindler, Ralph N.
The kinetics of the nitrate radical self-reaction
International Journal of Chemical Kinetics, 25 (10) :805-817
1993

DOI: 10.1002/kin.550251002

425.

Jensen, Per; Kozin, Igor N.
The Potential Energy Surface for the Electronic Ground State of H\(_{2}\)Se Derived from Experiment
Journal of Molecular Spectroscopy, 160 (1) :39-57
1993
Herausgeber: Academic Press

DOI: 10.1006/jmsp.1993.1155

424.

Jensen, Per; Kozin, Igor N.
The Potential Energy Surface for the Electronic Ground State of H\(_{2}\)Se Derived from Experiment
Journal of Molecular Spectroscopy, 160 (1) :39-57
1993
Herausgeber: Academic Press

DOI: 10.1006/jmsp.1993.1155

423.

Jensen, Per; Kozin, Igor N.
The Potential Energy Surface for the Electronic Ground State of H2Se Derived from Experiment
Journal of Molecular Spectroscopy, 160 (1) :39-57
1993
Herausgeber: Academic Press

DOI: 10.1006/jmsp.1993.1155

422.

Chong, Delano P.; Papousek, Dusan; Chen, Yit-Tsong; Jensen, Per
Theoretical vibrational and rotational energies and intensities of the HNSi and DNSi molecules
The Journal of Chemical Physics, 98 (2) :1352-1357
1993

DOI: 10.1063/1.464302

421.

Chong, Delano P.; Papousek, Dusan; Chen, Yit-Tsong; Jensen, Per
Theoretical vibrational and rotational energies and intensities of the HNSi and DNSi molecules
The Journal of Chemical Physics, 98 (2) :1352-1357
1993

DOI: 10.1063/1.464302

420.

Chong, Delano P.; Papousek, Dusan; Chen, Yit-Tsong; Jensen, Per
Theoretical vibrational and rotational energies and intensities of the HNSi and DNSi molecules
The Journal of Chemical Physics, 98 (2) :1352-1357
1993

DOI: 10.1063/1.464302

419.

Günther, Michael; Rentrop, R
TUM
1993

418.

Tausch, Michael W.
Unterrichtsmodell Ozon
FWU Magazin (3-4) :20
1993

417.

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

416.

Barclay, V. J.; Hamilton, I. P.; Jensen, Per
Vibrational levels for the lowest-lying triplet and singlet states of CH\(_{2}\) and NH\(_{2}\)\(^{+}\)
The Journal of Chemical Physics, 99 (12) :9709-9719
1993

DOI: 10.1063/1.465453

415.

Barclay, V. J.; Hamilton, I. P.; Jensen, Per
Vibrational levels for the lowest-lying triplet and singlet states of CH\(_{2}\) and NH\(_{2}\)\(^{+}\)
The Journal of Chemical Physics, 99 (12) :9709-9719
1993

DOI: 10.1063/1.465453

414.

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

1992

413.

Maten, E. J. W.; Melissen, J. B. M.
Simulation of inductive heating
{IEEE} Transactions on Magnetics, 28 (2) :1287--1290
März 1992
Herausgeber: Institute of Electrical and Electronics Engineers ({IEEE})

DOI: 10.1109/20.123925

412.

Kraemer, Wolfgang P.; Jensen, Per; Roos, B. O.; Bunker, Philip R.
Ab initio rotation-vibration energies and intensities for the HNC\(^{+}\) molecule
Journal of Molecular Spectroscopy, 153 (1-2) :240-254
1992

DOI: 10.1016/0022-2852(92)90472-Z

411.

Kraemer, Wolfgang P.; Jensen, Per; Roos, B. O.; Bunker, Philip R.
Ab initio rotation-vibration energies and intensities for the HNC\(^{+}\) molecule
Journal of Molecular Spectroscopy, 153 (1-2) :240-254
1992

DOI: 10.1016/0022-2852(92)90472-Z

410.

Kraemer, Wolfgang P.; Jensen, Per; Roos, B. O.; Bunker, Philip R.
Ab initio rotation-vibration energies and intensities for the HNC+ molecule
Journal of Molecular Spectroscopy, 153 (1-2) :240-254
1992

DOI: 10.1016/0022-2852(92)90472-Z

409.

Jensen, Per; Bunker, Philip R.; Epa, V. C.; Karpfen, Alfred
An ab initio calculation of the fundamental and overtone HCl stretching vibrations for the HCl dimer
Journal of Molecular Spectroscopy, 151 (2) :384-395
1992

DOI: 10.1016/0022-2852(92)90574-8

408.

Jensen, Per; Bunker, Philip R.; Epa, V. C.; Karpfen, Alfred
An ab initio calculation of the fundamental and overtone HCl stretching vibrations for the HCl dimer
Journal of Molecular Spectroscopy, 151 (2) :384-395
1992

DOI: 10.1016/0022-2852(92)90574-8

407.

Jensen, Per; Bunker, Philip R.; Epa, V. C.; Karpfen, Alfred
An ab initio calculation of the fundamental and overtone HCl stretching vibrations for the HCl dimer
Journal of Molecular Spectroscopy, 151 (2) :384-395
1992

DOI: 10.1016/0022-2852(92)90574-8

406.

Jensen, Per; Rohlfing, Celeste Michael; Alml{ö}f, Jan
Calculation of the complete-active-space self-consistent-field potential-energy surface, the dipole moment surfaces, the rotation-vibration energies, and the vibrational transition moments for C\(_{3}\)(X\verb=~= \(^{1}\)\(\Sigma\)\(_{g}\)\(^{+}\))
The Journal of Chemical Physics, 97 (5) :3399-3411
1992

DOI: 10.1063/1.462976

405.

Jensen, Per; Rohlfing, Celeste Michael; Alml{ö}f, Jan
Calculation of the complete-active-space self-consistent-field potential-energy surface, the dipole moment surfaces, the rotation-vibration energies, and the vibrational transition moments for C\(_{3}\)(X\verb=~= \(^{1}\)\(\Sigma\)\(_{g}\)\(^{+}\))
The Journal of Chemical Physics, 97 (5) :3399-3411
1992

DOI: 10.1063/1.462976