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Introduces papers from this area of expertise from the ISEF 1999 Proceedings. States the goal herein is one of identifying devices or systems able to provide prescribed performance. Notes that 18 papers from the Symposium are grouped in the area of automated optimal design. Describes the main challenges that condition computational electromagnetism’s future development. Concludes by itemizing the range of applications from small activators to optimization of induction heating systems in this third chapter.

A bi‐scalar boundary‐integral approach to the static and monoharmonic electromagnetic field

Discusses the 27 papers in ISEF 1999 Proceedings on the subject of electromagnetisms. States the groups of papers cover such subjects within the discipline as: induction machines; reluctance motors; PM motors; transformers and reactors; and special problems and applications. Debates all of these in great detail and itemizes each with greater in‐depth discussion of the various technical applications and areas. Concludes that the recommendations made should be adhered to.

Stationary and quasi‐stationary boundary‐integral models for magnetic and electromagnetic fields in 3D arrangements composed of coils, cores and screens are given. The test results obtained with the use of the authors' test program BIMS are presented.

In the paper the boundary‐integral model of the stationary magnetic field in a 3‐D linear region is presented. The region is bounded from inside or from outside by metallic materials of different permeability. Current sources of the field are represented by the filaments coinciding with axes of the conductors, and the magnetic field is described in terms of a scalar magnetic potential. Surface densities of the magnetic charge in monopole and dipole form are used as the variables in the boundary‐integral equations. The calculation of magnetic field distribution in the end region of an electrical machine may be effectively performed with the use of the proposed approach. Some results of computation of boundary quantities are presented.

The current pulse magnetizing process of permanent magnets is considered. General conditions for the design of a pulse magnetizer are given for the case when the magnetizing process is effected on the magnet put in free space. The boundary‐integral analysis of the magnetic field inside the magnet is presented. It concerns both the state corresponding to the maximum value of the magnetizing current pulse and the magnetized state after the full magnetizing.

Metallic elements placed in the vicinity of coils and conducting rings exert an influence on the inductance of them. Authors' BIMS package based on the boundary‐integral approach leads up to determine the monopole and/or dipole surface densities of the ‘magnetic charge’ on the walls of simple metallic boxes. The special considerations have been performed in order to study the influence of these boundary magnetic charge densities on the magnetic flux of the coils. The general algorithms for computing the magnetic flux is presented.

Magnetic field analysis of a permanent magnet put in free space can be effectively performed by a boundary‐integral technique completed with an iterative procedure following a non‐linear magnetic curve of magnetic material. The general idea of the boundary‐integral model of the permanent magnet is presented, the iterative algorithm and test software are described and the results of test computations are shown.

Introduces the fourth and final chapter of the ISEF 1999 Proceedings by stating electric and magnetic fields are influenced, in a reciprocal way, by thermal and mechanical fields. Looks at the coupling of fields in a device or a system as a prescribed effect. Points out that there are 12 contributions included ‐ covering magnetic levitation or induction heating, superconducting devices and possible effects to the human body due to electric impressed fields.

Recent progress in the development of electromagnetic field theory and sophisticated software for solution of complicated, non‐linear, 3‐D structures is not always accompanied with relatively cheap and simply presented engineering instructions, easy to use for regular industrial design. In the paper some theoretical and practical examples are given as to how one can get over a excessive calculating difficulties to obtain quickly simple design directions and reduce complicated theory to simple practical conclusions. The fast and cheap package RNM‐3D is validated by comparison with industrial test data and with the interactive graphics system is the final illustration of the effectiveness of such an approach. RNM‐3D is used successfully in many transformer works the world over.