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
- 2014
2975.
Ehrhardt, Matthias; Sánchez, Lucas Jódar; Villanueva Micó, Rafael Jacinto
Advanced computational engineering
20142974.
Ehrhardt, Matthias; Sánchez, Lucas Jódar; Villanueva Micó, Rafael Jacinto
Advanced computational engineering
International Journal of Computer Mathematics, 91 (1) :1–3
2014
Herausgeber: Taylor & Francis2973.
Ehrhardt, Matthias; Sánchez, Lucas Jódar; Villanueva Micó, Rafael Jacinto
Advanced computational engineering
International Journal of Computer Mathematics, 91 (1) :1–3
2014
Herausgeber: Taylor & Francis2972.
Advanced Mathematical Models and Numerical Techniques for Multiband Effective Mass Approximations
In M. Ehrhardt and Th. Koprucki, Editor, Band 94 aus LNCSE
Herausgeber: Springer, Heidelberg
20142971.
Jacob, Birgit; Partington, Jonathan R.; Pott, Sandra
Applications of {L}aplace-{C}arleson embeddings to admissibility and controllability
SIAM J. Control Optim., 52 (2) :1299--1313
20142970.
Jacob, Birgit; Partington, Jonathan R.; Pott, Sandra
Applications of Laplace-Carleson embeddings to admissibility and controllability
SIAM J. Control Optim., 52 (2) :1299--1313
20142969.
Klee, Sonja; Derpmann, Valerie; Wissdorf, Walter; Klopotowski, Sebastian; Kersten, Hendrik; Brockmann, Klaus Josef; Benter, Thorsten; Albrecht, Sascha; Bruins, Andries P.; Dousty, Faezeh; Kauppila, Tiina J.; Kostiainen, Risto; O'Brien, Rob; Robb, Damon B.; Syage, Jack A.
Are Clusters Important in Understanding the Mechanisms in Atmospheric Pressure Ionization? Part 1: Reagent Ion Generation and Chemical Control of Ion Populations
Journal of The American Society for Mass Spectrometry, 25 (8) :1310-1321
20142968.
Klee, Sonja; Derpmann, Valerie; Wissdorf, Walter; Klopotowski, Sebastian; Kersten, Hendrik; Brockmann, Klaus Josef; Benter, Thorsten; Albrecht, Sascha; Bruins, Andries P.; Dousty, Faezeh; Kauppila, Tiina J.; Kostiainen, Risto; O'Brien, Rob; Robb, Damon B.; Syage, Jack A.
Are Clusters Important in Understanding the Mechanisms in Atmospheric Pressure Ionization? Part 1: Reagent Ion Generation and Chemical Control of Ion Populations
Journal of The American Society for Mass Spectrometry, 25 (8) :1310-1321
20142967.
Klee, Sonja; Derpmann, Valerie; Wißdorf, Walter; Klopotowski, Sebastian; Kersten, Hendrik; Brockmann, Klaus Josef; Benter, Thorsten; Albrecht, Sascha; Bruins, Andries P.; Dousty, Faezeh; Kauppila, Tiina J.; Kostiainen, Risto; O'Brien, Rob; Robb, Damon B.; Syage, Jack A.
Are Clusters Important in Understanding the Mechanisms in Atmospheric Pressure Ionization? Part 1: Reagent Ion Generation and Chemical Control of Ion Populations
Journal of The American Society for Mass Spectrometry, 25 (8) :1310-1321
20142966.
Linnhoff, Luisa
Biodiversität und Naturverjüngung auf Kyrill-Sturmflächen
20142965.
Ankirchner, Stefan; Jeanblanc, Monique; Kruse, Thomas
BSDEs with singular terminal condition and a control problem with constraints
SIAM Journal on Control and Optimization, 52 (2) :893--913
2014
Herausgeber: SIAM2964.
Ankirchner, Stefan; Jeanblanc, Monique; Kruse, Thomas
BSDEs with singular terminal condition and a control problem with constraints
SIAM Journal on Control and Optimization, 52 (2) :893–913
2014
Herausgeber: Society for Industrial and Applied Mathematics2963.
Klee, Sonja; Thinius, Marco; Brockmann, Klaus Josef; Benter, Thorsten
Capillary atmospheric pressure chemical ionization using liquid point electrodes
Rapid Communications in Mass Spectrometry, 28 (14) :1591-1600
20142962.
Klee, Sonja; Thinius, Marco; Brockmann, Klaus Josef; Benter, Thorsten
Capillary atmospheric pressure chemical ionization using liquid point electrodes
Rapid Communications in Mass Spectrometry, 28 (14) :1591-1600
20142961.
Klee, Sonja; Thinius, Marco; Brockmann, Klaus Josef; Benter, Thorsten
Capillary atmospheric pressure chemical ionization using liquid point electrodes
Rapid Communications in Mass Spectrometry, 28 (14) :1591-1600
20142960.
Derpmann, Valerie; Müller, David; Bejan, Iustinian; Sonderfeld, Hannah; Wilberscheid, Sonja; Koppmann, Ralf; Brockmann, Klaus Josef; Benter, Thorsten
Capillary Atmospheric Pressure Electron Capture Ionization (cAPECI): A Highly Efficient Ionization Method for Nitroaromatic Compounds
Journal of The American Society for Mass Spectrometry, 25 (3) :329-342
20142959.
Derpmann, Valerie; M{ü}ller, David; Bejan, Iustinian; Sonderfeld, Hannah; Wilberscheid, Sonja; Koppmann, Ralf; Brockmann, Klaus Josef; Benter, Thorsten
Capillary Atmospheric Pressure Electron Capture Ionization (cAPECI): A Highly Efficient Ionization Method for Nitroaromatic Compounds
Journal of The American Society for Mass Spectrometry, 25 (3) :329-342
20142958.
Derpmann, Valerie; M{ü}ller, David; Bejan, Iustinian; Sonderfeld, Hannah; Wilberscheid, Sonja; Koppmann, Ralf; Brockmann, Klaus Josef; Benter, Thorsten
Capillary Atmospheric Pressure Electron Capture Ionization (cAPECI): A Highly Efficient Ionization Method for Nitroaromatic Compounds
Journal of The American Society for Mass Spectrometry, 25 (3) :329-342
20142957.
Bartel, Andreas; Ehrhardt, Matthias
Characteristic boundary conditions in the lattice Boltzmann method for fluid and gas dynamics
Journal of Computational and Applied Mathematics, 262 :51–61
2014
Herausgeber: North-Holland2956.
Bartel, Andreas; Ehrhardt, Matthias
Characteristic boundary conditions in the lattice Boltzmann method for fluid and gas dynamics
Journal of Computational and Applied Mathematics, 262 :51–61
2014
Herausgeber: North-Holland2955.
Tausch, Michael W.; Wachtendonk, M.; Bohrmann-Linde, Claudia; Krees, Simone; Buric, Ralf; Krollmann, Patrick; Schmitz, Wolfgang; Schulze, Ilona; Wambach, Heinz
CHEMIE 2000+ Lehrerband zur Einführungsphase
Herausgeber: C.C.Buchner, Bamberg
20142954.
Tausch, Michael W.; Wachtendonk, M.; Bohrmann-Linde, Claudia; Krees, Simone
CHEMIE 2000+ Qualifikationsphase
Herausgeber: C.C.Buchner, Bamberg
20142953.
Tausch, Michael W.; Flint, Alfred
Chemiedidaktik 2013 - Experimentell konzeptionelle Forschung in der Chemiedidaktik
Nachrichten aus der Chemie, 62 (3) :359
2014
Herausgeber: Wiley2952.
Ehrhardt, Matthias
Classical and quasi-newton methods for a meteorological parameters prediction boundary value problem
Applied Mathematics & Information Sciences, 8 (6) :2683–2693
2014
Herausgeber: Natural Sciences Publishing2951.
Ehrhardt, Matthias
Classical and quasi-newton methods for a meteorological parameters prediction boundary value problem
Applied Mathematics & Information Sciences, 8 (6) :2683–2693
2014
Herausgeber: Natural Sciences Publishing