Preface

The special issue is devoted to the papers that were presented at the International Symposium on Electromagnetic Fields in Electrical Engineering ISEF’05. It was organized this time by the University of Vigo, Spain, thus the city of Vigo is the reference city for the conference. But the venue of the conference was the Royal Village of Baiona, which lies just on the Atlantic shore. The Spanish province, Galicia, which Vigo and Baiona belong to, is the place which is devoted to God for its beauty, people, good environment, wine and cuisine and its cultural heritage. It was all of ISEF’05 participants’ privilege to be invited to that place.

The ISEF travel through Europe, held many times in Poland, where it was initiated in 1985 in Warsaw, after visiting very interesting cities, like Pavia(twice), Southampton, Thessalonica, Maribor celebrated its 20th anniversary just in Vigo and Baiona. No place seems to be more adequate for such event.

After the selection process 211 papers have been accepted for the presentation at the Symposium and almost all of them were presented at the conference both orally and in the poster sessions. The papers have been divided into the following groups:

• Computational Electromagnetics

• Electromagnetic Engineering

• Coupled Field and Special Applications

• Micro- and Special-Devices

• Bioelectromagnetics and Electromagnetic Hazards

• Magnetic Material Modelling

It is the tradition of the ISEF meetings that they comprise quite a vast area of computational and applied electromagnetics. Moreover, the ISEF symposia aim at joining theory and practice, thus the majority of papers are deeply rooted in engineering problems, being simultaneously of high theoretical level. Bearing this tradition we hope to touch the heart of the matter in electromagnetism.

The present issue of COMPEL contains 26 papers which have been selected by the editors on the basis of the reviewing process done by the chairmen of the sessions. This selection, however, gave the number of papers much bigger than the number imposed by the COMPEL. Thus, going to the number required we also took into account some special factor, namely the specific character of COMPEL, its differentia specifica. The selected papers deal rather with computer modelling and computations while the remaining part of high-qualified papers concern rather measurement, physics and design problems. Finally, the papers directed to COMPEL have been refereed by the ISEF Editorial Board with regard to COMPEL requirements. The remained contributions will be published as a book in IOS Press series: Studies in Applied Electromagnetics and Mechanics.

To introduce a prospective reader into a volume contents, we decided to present in a very short way the topics which are considered throughout the journal. The topics are ordered in the sequence as the papers appear in the volume. Thus, in particular the contributions deal with:

• most famous Einstein’s works, published exactly in 1905, showing their essence and how Enstein’s concept of physical world contradicts or follows the Faraday concept of electromagnetic field,

• mostly used requirements in computational electromagnetism – three useful computer tools are proposed,

• nonlinear magnetostatic field problems being solved with the integral equation method and different indirect formulations – the improved computational accuracy is demonstrated with some numerical examples,

• 3D multi-objective approach regarding both magnetic and thermal characteristics associated with design of actuators, particularly of a C-core actuator and a single-phase induction motor,

• network models of an electromagnetic field containing both eddy and displacement currents and consisting of magnetic and electric networks coupled via sources – the analogy between the finite element method and the loop and nodal formulations of electric circuits is emphasised,

• effective methods for computing electromagnetic field sensitivity in the time domain versus conductivity perturbations in finite elements,

• a fast evolutionary-deterministic algorithm to solve constrained multimodal optimization problems, especially various current field problems to find the dangerous values of touch voltages generated by various grounding systems,

• an approach to be used with different models for anisotropy in the finite element method, and how it can be integrated in its formulation – the approach can be applied to determine the parameters of grain-oriented steel sheets which are usually used in power transformers,

• algorithm used for identifying the profile of cracks. This typical NDT inverse problem is solved by direct method based on Fuzzy Logic system,

• a methodology using the Schwarz-Christoffel transformation in order to extract a sub-domain with suitable boundary conditions from a simply-connected source-free two-dimensional field domain,

• application of the integro-differential approach – the theoretical background of the method as well as numerical examples are presented,

• dual finite element formulations are developed for modelling both inductive and capacitive effects in massive inductors. Mixed finite elements are used to satisfy each chosen conformity level for the unknown fields and to naturally define the global quantities involved in the inductive and capacitive circuit relations, to be used in circuit coupling,

• new open boundary condition to be used in conjunction with the finite integration technique for the modelling of passive on-chip components,

• finite element analysis of a broad band loop antenna, emphasizing the calculation of the impedance of the antenna over a wide frequency band –results were compared those obtained by boundary element method,

• evaluation of the crosstalk models developed for a shareware version of SPICE, the transmission line model is compared with π lumped circuit models by varying the number of cells,

• optimisation of 3D EMC structures formed by composite left-handed metamaterials through a new frequency-dependent ADI-FDTD method,

• analysis of SAR coefficient both numerically and experimentally by FDTD method and waveguide mode, respectively,

• the numerical modelling of 3D structure of surface micromachined (MEMS)accelerometers leading to final structure design, defined as a basic structure for stress analysis,

• an approach of calculation “high frequency surface loss” in a 6-phase induction machine supplied by fundamental and 3rd harmonics of current course,

• an analysis of a new outer-rotor permanent magnet brushless DC motor by means of the Finite Element Method, with special attention to cogging torque level,magnetic field and performance characteristics,

• the comparison between the performances of the exterior-rotor permanent magnet synchronous motors with distributed windings and the performances of the exterior-rotor permanent magnet synchronous motors with concentrated windings,

• a low-cost and easy to use measurement method for characterizing magnetic material B(H) relation up to medium frequencies providing an acceptable overall accuracy of the acquired data,

• a design of a planar motor with six degrees of freedom is introduced in this paper. This planar motor is magnetically levitated in four degrees of freedom and magnetically driven in the other two,

• state of art in finite element analysis solvers for accurate modelling of the magnetisation of hard magnetic material sections,

• the analysis of eddy current loss in permanent magnets of IPM motors using the 3D finite element method, investigating the effects of the input current phase on the eddy current loss are quantitatively clarified, and

• a software application for simulating and calculating the magnetic field during the design of domestic/industrial electrical installations in order to predict the magnetic field that may be obtained within the structure, preventing any anomalous value of the magnetic field that might affect any inhabitant of the building.

We, the Editors of the special issue, would like to express our thanks to COMPEL for giving us the opportunity to present something which is untouchable, namely the flavour of the ISEF meeting. We also thank our colleagues for their help, efficient work and valuable contribution to reviewing process of the papers accepted to this issue.

Finally, we would like to wish the prospective readers of the issue to find within it the subjects they are particularly interested in.

Slawomir WiakGuest editor

Xose Lopez M. Fernandez and Andrzej KrawczykCo-editors