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SCEE-2000
Scientific Computing in Electrical Engineering
August 20 - 23, 2000
Warnemünde, Germany

 
 
Andreas Blaszczyk, (ABB, Heidelberg)
Computational Electromagnetism in Transformer and Switchgear Design. Current Trends

   Computation of electromagnetic fields has a long tradition in design of high voltage equipment like transformers and switchgear.  In particular 2D analysis became an important part of the industrial design process. Since mid 90s a new design technology based on 3D solid modeling has been widely introduced. Designers develop virtual prototypes using efficient 3D modeling systems. These prototypes are used for creation of technical drawings and in some cases are directly applied in manufacturing. A designer experienced in 3D CAD modeling is able to create a virtual prototype of new components within few hours. Even a complex assembly representing the whole product can be accomplished within few days. Since the models are now precisely defined in a computer the designers naturally ask for simulation. The efficiency of 3D simulation is however strongly limited. The main barriers we would like to discuss are as follows: 

(1) Complexity of simulated phenomena. Three basic analysis types including dielectric, electromechanical and thermal design require the computation of electrostatic fields, electromagnetic forces and losses respectively. But this is only the first step in the analysis. For example, the goal of dielectric design is prediction of the withstand voltage that cannot be obtained directly from the standard analysis. Usually empirical rules specific for oil and gases are applied in evaluation of electrostatic results. In case of the electromechanical and thermal analyses the material stresses and temperature rise are of interest. They can be obtained by employing mechanical and thermal solvers that use the previously calculated electromagnetic forces and losses as loads.

(2) Discretization of complex 3D geometries. In particular the generation of volume mesh in the space outside of solid parts (usually required by finite element method) seems to be a significant barrier in industrial applications. Therefore the use of the boundary element method is preferable. It requires mainly discretization of surfaces that is much easier for standard mesh generators.

(3) Access to resources. The expensive simulation tools are used in many medium size companies just few times a year. Furthermore, the education of people and maintenance of the expertise are also expensive. Consequently, very attractive is access to centrally installed and maintained resources over Intranet. Included is access to: floating software licenses, compute servers with installed solvers, Web servers with updated description of simulation procedures and technical standards for dimensioning criteria, interactive hot-line support. In particular large but decentralized companies can efficiently implement this kind of access using Web/Java technology. 

Based on selected examples from the transformer and switchgear design we will show our approach in organizing an efficient simulation environment that removes the described barriers.
 

 

SCEE-2000
last updated 14.06.2000