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

1985

135.

Holstein, K. J.; Fink, Ewald H.; Wildt, Jürgen; Zabel, Friedhelm
A~2A' → X~2A" emission spectrum of the HS2 radical
Chemical Physics Letters, 113 (1) :1-7
1985

DOI: 10.1016/0009-2614(85)85001-6

134.

Tausch, Michael W.
Aktivierungsenergie - was ist das?
Praxis der Naturwissenschaften (Chemie), 34 :33
1985

133.

Phillips, R.A.; Buenker, Robert J.; Beardsworth, R.; Bunker, Philip R.; Jensen, Per; Kraemer, Wolfgang P.
An ab initio study of the rotation-vibration energy levels of GeH\(_{2}\) in the a\verb=~=\(^{3}\)B\(_{1}\) state
Chemical Physics Letters, 118 (1) :60-63
1985

DOI: 10.1016/0009-2614(85)85266-0

132.

Phillips, R.A.; Buenker, Robert J.; Beardsworth, R.; Bunker, Philip R.; Jensen, Per; Kraemer, Wolfgang P.
An ab initio study of the rotation-vibration energy levels of GeH\(_{2}\) in the a\verb=~=\(^{3}\)B\(_{1}\) state
Chemical Physics Letters, 118 (1) :60-63
1985

DOI: 10.1016/0009-2614(85)85266-0

131.

Phillips, R.A.; Buenker, Robert J.; Beardsworth, R.; Bunker, Philip R.; Jensen, Per; Kraemer, Wolfgang P.
An ab initio study of the rotation-vibration energy levels of GeH2 in the a~3B1 state
Chemical Physics Letters, 118 (1) :60-63
1985

DOI: 10.1016/0009-2614(85)85266-0

130.

Kling, H.-W.; Hartkamp, H.; Buchholz, N.
Matrixunabhängige kontinuierliche Dampfraum-Gas-Chromatographie
Fresenius' Journal of Analytical Chemistry, 320 (4) :341--346
1985

129.

Winkler, R.
Path-following for two-point boundary value problems
, Seminarbericht 78 der Sektion MathematikBand78
Humboldt-Universität zu Berlin
1985

128.

Spirko, Vladim{í}r; Jensen, Per; Bunker, Philip R.; Cejchan, A.
The development of a new Morse-oscillator based rotation-vibration Hamiltonian for H\(_{3}\)\(^{+}\)
Journal of Molecular Spectroscopy, 112 (1) :183-202
1985

DOI: 10.1016/0022-2852(85)90203-6

127.

Spirko, Vladim{í}r; Jensen, Per; Bunker, Philip R.; Cejchan, A.
The development of a new Morse-oscillator based rotation-vibration Hamiltonian for H\(_{3}\)\(^{+}\)
Journal of Molecular Spectroscopy, 112 (1) :183-202
1985

DOI: 10.1016/0022-2852(85)90203-6

126.

Spirko, Vladimír; Jensen, Per; Bunker, Philip R.; Cejchan, A.
The development of a new Morse-oscillator based rotation-vibration Hamiltonian for H3+
Journal of Molecular Spectroscopy, 112 (1) :183-202
1985

DOI: 10.1016/0022-2852(85)90203-6

125.

Lamour, R.; Hanke, M.; Winkler, R.
The program system ‘RWA’ (version 2) for the solution of TPBVP - fundamentals and algorithms
, Seminarbericht 67 der Sektion MathematikBand67
Humboldt-Universität zu Berlin
1985
1984

124.

Morillon-Chapey, M.; Guelachvili, Guy; Jensen, Per
Analysis of the high resolution spectrum of the \(\nu\)\(_{2}\) and \(\nu\)\(_{5}\) absorption bands of methyl chloride
Canadian Journal of Physics, 62 (3) :247-253
1984
Herausgeber: NRC Research Press Ottawa, Canada

DOI: 10.1139/p84-039

123.

Morillon-Chapey, M.; Guelachvili, Guy; Jensen, Per
Analysis of the high resolution spectrum of the \(\nu\)\(_{2}\) and \(\nu\)\(_{5}\) absorption bands of methyl chloride
Canadian Journal of Physics, 62 (3) :247-253
1984
Herausgeber: NRC Research Press Ottawa, Canada

DOI: 10.1139/p84-039

122.

Morillon-Chapey, M.; Guelachvili, Guy; Jensen, Per
Analysis of the high resolution spectrum of the ν2 and ν5 absorption bands of methyl chloride
Canadian Journal of Physics, 62 (3) :247-253
1984
Herausgeber: NRC Research Press Ottawa, Canada

DOI: 10.1139/p84-039

121.

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\(_{2}\)1 band systems of AsCl and AsBr
Chemical Physics Letters, 111 (1-2) :100-104
1984

DOI: 10.1016/0009-2614(84)80444-3

120.

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\(_{2}\)1 band systems of AsCl and AsBr
Chemical Physics Letters, 111 (1-2) :100-104
1984

DOI: 10.1016/0009-2614(84)80444-3

119.

Winter, R.; Kruse, H.; Fink, Ewald H.; Wildt, J{ü}rgen; Zabel, Friedhelm
b\(^{1}\)\(\Sigma\)\(^{+}\) Emissions from group V-VII diatomic molecules. b0\(^{+}\) → X\(_{1}\)0\(^{+}\), X\(_{2}\)1 emissions of AsI and SbI
Chemical Physics Letters, 104 (4) :383-388
1984

DOI: 10.1016/0009-2614(84)80084-6

118.

Winter, R.; Kruse, H.; Fink, Ewald H.; Wildt, J{ü}rgen; Zabel, Friedhelm
b\(^{1}\)\(\Sigma\)\(^{+}\) Emissions from group V-VII diatomic molecules. b0\(^{+}\) → X\(_{1}\)0\(^{+}\), X\(_{2}\)1 emissions of AsI and SbI
Chemical Physics Letters, 104 (4) :383-388
1984

DOI: 10.1016/0009-2614(84)80084-6

117.

Kruse, H.; Winter, R.; Fink, Ewald H.; Wildt, Jürgen; Zabel, Friedhelm
b1Σ+ Emissions from group V-VII diatomic molecules. b0+ → X10+, X21 band systems of AsCl and AsBr
Chemical Physics Letters, 111 (1-2) :100-104
1984

DOI: 10.1016/0009-2614(84)80444-3

116.

Winter, R.; Kruse, H.; Fink, Ewald H.; Wildt, Jürgen; Zabel, Friedhelm
b1Σ+ Emissions from group V-VII diatomic molecules. b0+ → X10+, X21 emissions of AsI and SbI
Chemical Physics Letters, 104 (4) :383-388
1984

DOI: 10.1016/0009-2614(84)80084-6

115.

Jensen, Per
C\(_{3}\)O\(_{2}\) as a semirigid bender: The degenerate \(\nu\)\(_{5}\) state
Journal of Molecular Spectroscopy, 104 (1) :59-71
1984

DOI: 10.1016/0022-2852(84)90245-5

114.

Jensen, Per
C\(_{3}\)O\(_{2}\) as a semirigid bender: The degenerate \(\nu\)\(_{5}\) state
Journal of Molecular Spectroscopy, 104 (1) :59-71
1984

DOI: 10.1016/0022-2852(84)90245-5

113.

Jensen, Per
C3O2 as a semirigid bender: The degenerate ν5 state
Journal of Molecular Spectroscopy, 104 (1) :59-71
1984

DOI: 10.1016/0022-2852(84)90245-5

112.

Kreglewski, Marek; Jensen, Per
Determination of the skeletal bending potential function for SiH\(_{3}\)NCO from the microwave spectrum
Journal of Molecular Spectroscopy, 103 (2) :312-320
1984

DOI: 10.1016/0022-2852(84)90058-4

111.

Kreglewski, Marek; Jensen, Per
Determination of the skeletal bending potential function for SiH\(_{3}\)NCO from the microwave spectrum
Journal of Molecular Spectroscopy, 103 (2) :312-320
1984

DOI: 10.1016/0022-2852(84)90058-4