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



1983

75.

Holstein, K. J.; Fink, Ewald H.; Zabel, Friedhelm
The \(\nu\)\(_{3}\) vibration of electronically excited HO\(_{2}\)(A\(^{2}\)A')
Journal of Molecular Spectroscopy, 99 (1) :231-234
1983

74.

Jensen, Per; Bunker, Philip R.
The application of the nonrigid bender Hamiltonian to a quasilinear molecule
Journal of Molecular Spectroscopy, 99 (2) :348-356
1983

73.

Jensen, Per; Bunker, Philip R.
The application of the nonrigid bender Hamiltonian to a quasilinear molecule
Journal of Molecular Spectroscopy, 99 (2) :348-356
1983

72.

Jensen, Per; Bunker, Philip R.
The application of the nonrigid bender Hamiltonian to a quasilinear molecule
Journal of Molecular Spectroscopy, 99 (2) :348-356
1983

71.

Winnewisser, Brenda P.; Jensen, Per
The infrared spectrum of fulminic acid, HCNO, in the \(\nu\)\(_{4}\) fundamental region
Journal of Molecular Spectroscopy, 101 (2) :408-421
1983

70.

Winnewisser, Brenda P.; Jensen, Per
The infrared spectrum of fulminic acid, HCNO, in the \(\nu\)\(_{4}\) fundamental region
Journal of Molecular Spectroscopy, 101 (2) :408-421
1983

69.

Winnewisser, Brenda P.; Jensen, Per
The infrared spectrum of fulminic acid, HCNO, in the ν4 fundamental region
Journal of Molecular Spectroscopy, 101 (2) :408-421
1983

68.

Jensen, Per
The nonrigid bender Hamiltonian for calculating the rotation-vibration energy levels of a triatomic molecule
Computer Physics Reports, 1 (1) :1-55
1983

67.

Jensen, Per
The nonrigid bender Hamiltonian for calculating the rotation-vibration energy levels of a triatomic molecule
Computer Physics Reports, 1 (1) :1-55
1983

66.

Jensen, Per
The nonrigid bender Hamiltonian for calculating the rotation-vibration energy levels of a triatomic molecule
Computer Physics Reports, 1 (1) :1-55
1983

65.

Holstein, K. J.; Fink, Ewald H.; Zabel, Friedhelm
The ν3 vibration of electronically excited HO2(A2A')
Journal of Molecular Spectroscopy, 99 (1) :231-234
1983
1982

64.

Winter, R.; Barnes, Ian; Fink, Ewald H.; Wildt, J{ü}rgen; Zabel, Friedhelm
b\(^{1}\)\(\Sigma\)\(^{+}\) and a\(^{1}\)\(\Delta\) emissions from group VI-VI diatomic molecules b0\(_{g}\)\(^{+}\) → X\(^{2}\)1\(_{g}\) emissions of Se\(_{2}\) and Te\(_{2}\)
Chemical Physics Letters, 86 (2) :118-122
1982

63.

Winter, R.; Barnes, Ian; Fink, Ewald H.; Wildt, J{ü}rgen; Zabel, Friedhelm
b\(^{1}\)\(\Sigma\)\(^{+}\) and a\(^{1}\)\(\Delta\) emissions from group VI-VI diatomic molecules b0\(_{g}\)\(^{+}\) → X\(^{2}\)1\(_{g}\) emissions of Se\(_{2}\) and Te\(_{2}\)
Chemical Physics Letters, 86 (2) :118-122
1982

62.

Winter, R.; Barnes, Ian; Fink, Ewald H.; Wildt, J{ü}rgen; Zabel, Friedhelm
b\(^{1}\)\(\Sigma\)\(^{+}\) and a\(^{1}\)\(\Delta\) emissions from group VI-VI diatomic molecules: b0\(^{+}\) → X\(_{1}\)0\(^{+}\), X\(_{2}\)1 emissions of TeO and TeS
Journal of Molecular Structure, 80 :75-82
1982

61.

Winter, R.; Barnes, Ian; Fink, Ewald H.; Wildt, J{ü}rgen; Zabel, Friedhelm
b\(^{1}\)\(\Sigma\)\(^{+}\) and a\(^{1}\)\(\Delta\) emissions from group VI-VI diatomic molecules: b0\(^{+}\) → X\(_{1}\)0\(^{+}\), X\(_{2}\)1 emissions of TeO and TeS
Journal of Molecular Structure, 80 :75-82
1982

60.

Kruse, H.; Winter, R.; Fink, Ewald H.; Wildt, J{ü}rgen; Zabel, Friedhelm
b\(^{1}\)\(\Sigma\)\(^{+}\) emissions from group V-VII diatomic molecules: b0\(^{+}\) → X\(_{1}\)0\(^{+}\), X\(_{2}\)0\(^{+}\) emissions of SbBr
Chemical Physics Letters, 93 (5) :475-479
1982

59.

Kruse, H.; Winter, R.; Fink, Ewald H.; Wildt, J{ü}rgen; Zabel, Friedhelm
b\(^{1}\)\(\Sigma\)\(^{+}\) emissions from group V-VII diatomic molecules: b0\(^{+}\) → X\(_{1}\)0\(^{+}\), X\(_{2}\)0\(^{+}\) emissions of SbBr
Chemical Physics Letters, 93 (5) :475-479
1982

58.

Winter, R.; Barnes, Ian; Fink, Ewald H.; Wildt, Jürgen; Zabel, Friedhelm
b1Σ+ and a1Δ emissions from group VI-VI diatomic molecules b0g+ → X21g emissions of Se2 and Te2
Chemical Physics Letters, 86 (2) :118-122
1982

57.

Winter, R.; Barnes, Ian; Fink, Ewald H.; Wildt, Jürgen; Zabel, Friedhelm
b1Σ+ and a1Δ emissions from group VI-VI diatomic molecules: b0+ → X10+, X21 emissions of TeO and TeS
Journal of Molecular Structure, 80 :75-82
1982

56.

Kruse, H.; Winter, R.; Fink, Ewald H.; Wildt, Jürgen; Zabel, Friedhelm
b1Σ+ emissions from group V-VII diatomic molecules: b0+ → X10+, X20+ emissions of SbBr
Chemical Physics Letters, 93 (5) :475-479
1982

55.

Tausch, Michael W.
Modelle im Chemieunterricht
Der mathematische und naturwissenschaftliche Unterricht (MNU), 35 :226
1982

54.

Becker, Karl Heinz; Horie, O.; Schmidt, V. H.; Wiesen, Peter
Spectroscopic identification of C\(_{2}\)O radicals in the C\(_{3}\)O\(_{2}\) + O flame system by laser-induced fluorescence
Chemical Physics Letters, 90 (1) :64-68
1982

53.

Becker, Karl Heinz; Horie, O.; Schmidt, V. H.; Wiesen, Peter
Spectroscopic identification of C\(_{2}\)O radicals in the C\(_{3}\)O\(_{2}\) + O flame system by laser-induced fluorescence
Chemical Physics Letters, 90 (1) :64-68
1982

52.

Becker, Karl Heinz; Horie, O.; Schmidt, V. H.; Wiesen, Peter
Spectroscopic identification of C2O radicals in the C3O2 + O flame system by laser-induced fluorescence
Chemical Physics Letters, 90 (1) :64-68
1982

51.

Jensen, Per; Brodersen, Svend
The \(\nu\)\(_{5}\) Raman band of CH\(_{3}\)CD\(_{3}\)
Journal of Raman Spectroscopy, 12 (3) :295-299
1982