O. Vogel, and J. Ulm
Proportional solenoids are well-known and used in a wide range of applications today. This paper is about methods of influencing the characteristic force-stroke-curves of magnetic actuators by means of different pole geometries. The conical design of the stator pole which is mostly used to accomplish proportional solenoids is analyzed by both a simple analytic reluctance model and a FEM model ...
Multiphysics Simulation of Thermoelectric Systems - Modeling of Peltier-Cooling and Thermoelectric Generation
Fraunhofer-Institute for Physical Measurement-Techniques (IPM), Freiburg, Germany
Electro-thermal interaction is commonly considered only as a matter of joule heating. In addition, the Seebeck-, Peltier- and Thompson-Effects are significant in materials with high thermoelectric figure of merit Z. These thermoelectric materials have a high Seebeck-coefficient α, a good electric conductivity σ, and a poor thermal conductivity λ. They have widespread areas of ...
V. Bhatt, R.S Rautela, P. Sharma, D.C. Tiwari, and S. Khushu
Institute of Nuclear Medicine & Allied Sciences (DRDO), Delhi, India
The Helmholtz Coil generates a uniform magnetic field. The commercially available large-size Helmholtz coils prove to be very expensive. This paper describes the economical method of designing and construction of a Helmholtz coil. COMSOL Multiphysics AC/DC Module simulated results and actual results were compared in this study. The coil serves as a component in the system for Hyperpolarisation ...
P.A. Wallace, M. Alsharif, D.M. Hepburn, and C. Zhou
Department of Energy Systems Engineering, Glasgow Caledonian University, Glasgow, United Kingdom
Two simulations of the performance of a Paper Insulated Lead Covered (PILC) Medium Voltage (MV) underground cable are presented. The first presents the thermal response of a cable, over seven days, to a realistic load with a diurnal variation. The second concentrates on the variation of the electric field stress within the cable over a single AC cycle. The effects of a void defect within the ...
Dr., ABB Corporate Research, Sweden
Outline of presentation: In electromagnetic technology applications the finite element method is very well suited for a wide range of problem types For many cases, in particular when inhomogeneous materials having complex properties are involved as well as when multiphysics couplings are essential, it is the only option available The somewhat unfavourable performance scaling with problem ...
U. N. Mughal, M. S. Virk
Narvik University College, Narvik, Norway
Atmospheric ice is a very complex material with varying electrical properties due to different polymorphs of ice itself. Also, if the medium to be considered is snow, then density becomes an additional parameter because it is a mixture of three dielectrics water, ice and air. The permittivity and loss tangent of naturally occurring ice and snow shows lot of variation at different conditions ...
H. Lorenzen, J. Timmerberg, and S. Mylvaganam
Department of Electrical Engineering, UAS OOW, Wilhelmshaven, Germany
Department Technology/Engineering, Telemark University College, Porsgrunn, Norway
Efforts involving simulation of transmission line networks necessitate the accurate values of the parameters of the lines. In this paper, as an attempt in estimating such parameters, the parameters of high voltage asymmetric power lines are calculated. In the process of estimation, the three phase equivalent circuit model is used. The resistance and inductance of such lines are dependent ...
Modelling the Effects of Temperature and Moisture Ingress on Capacitance and Dissipation Factor Measurements within Oil Impregnated Paper Transformer Bushings
D. Smith, S.G. McMeekin, B.G. Stewart, and P.A. Wallace
Glasgow Caledonian University, Glasgow, Scotland, United Kingdom
The majority of power transformer high voltage bushings today are of the condenser oil impregnated paper (OIP) type. The ingress of moisture, through the deterioration of the bushing over time, can result in a significant reduction in life and is a major failure mode of these bushings. Currently, the measurement of capacitance and dissipation factor is the most common method used to assess the ...
Transient Electromagnetic-Thermal FE-Model of a SPICE-Coupled Transformer Including Eddy Currents with COMSOL Multiphysics 4.2
H. Neubert, R. Disselnkötter, and T. Bödrich
Technische Universität Dresden, Institute of Electromechanical and Electronic Design, Dresden, Germany
ABB AG, Forschungszentrum Deutschland, Ladenburg, Germany
Current transformers are used to measure currents in power grid systems. They are characterized by strong interactions between external electrical sources and loads respectively and the magnetic subsystem. Self-heating due to losses has to be considered because of the temperature-dependent material behaviour. The paper presents a transient 3D FEA transformer model which includes a H(|B|) ...
Wenger Engineering, Ulm, Germany
The ampacity of a cable depends on the cross section of its conductor. When selecting a cable design for a specific application it is of interest to choose the lowest possible conductor cross section in order to reduce material costs. Therefore an exact calculation of the ampacity is necessary (it is usually limited by the thermal resistance of the insulating cable materials). Commonly the ...