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Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community. Observes that computer package implementation theory contributes to clarification. Discusses the areas covered by some of the papers ‐ such as artificial intelligence using fuzzy logic. Includes applications such as permanent magnets and looks at eddy current problems. States the finite element method is currently the most popular method used for field computation. Closes by pointing out the amalgam of topics.

The paper seeks to present a methodology of computer simulation of 3D transient electromagnetic fields, losses and forces due to negative sequence currents in fragments of large synchronous turbogenerator rotors. The methodology allows for the preparation of initial data for further computations of thermal and mechanical behaviour of rotors.

The governing equations for 3D negative sequence transient electromagnetic fields with the Coulomb gauge using magnetic vector potential and scalar electric potential A, V – A are solved by the nodal finite element method in a Cartesian coordinate system moving synchronously with the rotor.

The presented methodology of 3D transient electromagnetic phenomena computation seems to be effective because the electromagnetic field in the rotor of a synchronous generator is generally three dimensional, and therefore 2D field‐computation approaches and software are not able to simulate intrinsically 3D electromagnetic processes in turbogenerator rotors.

Currently it is difficult to carry out accurate numerical simulation of 3D transient electromagnetic fields and therefore losses and forces within the whole structure of the rotor because of the resulting huge computational expenses. This paper is devoted to the finite element analysis of electromagnetic fields, losses and forces in separate structural parts of the rotor. As an example of practical utilization of the developed technique, the computer simulation of electromagnetic phenomena in junctions of nonmagnetic rotor slot wedges of a 300 MVA class synchronous turbogenerator is carried out.

The methodology can successfully be used during the design process of modern large synchronous turbogenerators.

This paper presents numerical analysis of intrinsically 3D transient electromagnetic phenomena in large turbogenerator rotors.

The purpose of this paper is to introduce and investigate a useful and practicable definition of the shielding effectiveness (SE) of enclosures for transient near‐field sources.

The transient SE is defined as the ratio of electromagnetic energies absorbed by an unshielded and by a shielded vanishingly small load. That ratio can be found analytically by means of a suitable spherical‐multipole approach. The SE can be reduced to easily measurable values of frequency‐domain electric and magnetic fields.

Suitable factors are introduced which depend on the frequency and on the distance between the dipole source and the measurement point inside the shield. The proposed definition has been analytically evaluated and validated for the case of a cylindrical shield.

The paper extends a recently proposed definition of the transient SE for plane‐wave incidence to the case of a dipole near‐field source.

System contains units which are the tools for the actuators designs, optimization and steady‐states or transients simulation. Design and optimization process has been based on the equivalent circuit model with “field” procedures for concentrated circuit parameters calculation. For the optimization the penalty function method combined with the conjugate gradients method has been adopted. In the steady‐states simulation, the entirely 2D or 3D field formulation has been employed. Whereas in transients, it is assumed that the field is produced under the time‐varying voltage constraints, so the combined field‐circuit formulation has been applied.

The paper deals with a coupled field‐circuit simulation of transient and dynamic states in a non‐linear axisymmetrical electromagnetic device. The mathematical model of the dynamic phenomena includes: an equation of transient electromagnetic field in a non‐linear conducting and moving medium, equations of the converter electric circuits and the equation of mechanical motion. The numerical implementation of the algorithm is based on the finite element method. The Crank‐Nicholson scheme for time discretization has been applied. In order to include nonlinearity, the Newton‐Raphson process has been adopted. The influence of the saturation effect on the dynamic characteristics of the device has been investigated.

This paper aims to elaborate the method and algorithm for the analysis of the influence of high temperature on electric and thermal properties of the materials, as well as thermal phenomena process.

The paper presents specially author’s software for the transient finite element analysis of coupled electromagnetic-thermal problems in a squirrel cage induction motor. The numerical implementation is based on finite element method and step-by-step algorithm. The nonlinearity of a magnetic circuit, the dependence of electric and thermal parameters on temperature, the movement of a rotor and skewed rotor bars have been taken into account. To verify the developed algorithm and software, the influence of high ambient temperature on selected electromagnetic and thermal parameters of the induction motor was examined.

The results of simulations compared with measurements confirm the adequacy of this approach to the analysis of coupled electromagnetic-thermal problems.

3D effects have only been taken into account when using quasi-3D techniques (e.g. the multi-slice for skewed rotor slots).

The author’s software developed can be useful in the analysis and design of squirrel cage motors, especially motors working in high ambient temperature.

The paper offers appropriate author’s software for the transient and steady-state analysis of coupled electromagnetic and thermal problems in squirrel cage motors with skewed slots.

This paper deals with coupled electromagnetic, hydrodynamic and mechanical motion phenomena in magnetorheological fluid brakes. The governing equations of these phenomena are presented. The numerical implementation of the mathematical model is based on the finite element method and a step‐by‐step algorithm. A computer program based on this algorithm was used to simulate the transients in a prototype of magnetorheological brake. The results of the calculations and measurements are presented.

This paper presents a coupled field‐circuit simulation of transients in a non‐linear electromagnetic device supplied by electronic power converters (inverters, PWM systems). The eddy currents induced in solid cores are considered. The mathematical model of transients includes: equation of electromagnetic field, equations of the electric circuits and equation of motion. Numerical implementation of the algorithm is based on the finite element method. For time‐stepping the Cranck‐Nicholson scheme has been applied.

A finite‐difference‐scheme for axisymmetric transient electromagnetic fields is presented, which also takes into account an arbitrary prescribed motion of a substructure and motion inductive effects arising therefrom. For the arrangement at rest transient effects governed by the consequences of electromagnetic induction, e.g. the skin effect, are also taken into account. The behaviour of lumped external network elements is modelled by additional equations. A remeshing procedure is avoided by a special modelling technique. The method is tested for simple arrangements with axial and radial, i.e. expansive motion of a rectangular ring cross‐section. Comparisons with lumped parameter analysis are carried out.

The aim of the paper is to find the effective methods of power loss reduction in axisymmetric electromagnetic devices and improve their dynamic parameters. As an example the linear tubular motor is considered.

The elaborated algorithm has been applied to analyze the dynamic operation of axisymmetric electromagnetic devices, especially tubular linear induction motors. The mathematical model of transients includes: the equation of electromagnetic field, the equations of electric circuits and the equation of motion. The model is based on the finite element method. For the time‐stepping, the Cranck‐Nicholson scheme is applied. In order to include non‐linearity, the Newton‐Raphson process is adopted.

In order to reduce the influence of eddy currents, it is suggested that the solid core should be equipped with one or several radial slots. In such a case, the radial component of eddy currents occurs near the slot and disturbs the axial symmetry of the system. However, when the width of the slot is small, the fields generated by the radial component of eddy currents on both sides of the slot practically cancel one another and the system can still be considered axisymmetric. Another solution given in the paper consists of replacing the cylindrical core with a system of flat laminated segments. In such a case, saturation of the ferromagnetic parts is greater than in the case of classical axisymmetric core.

In the paper, new quasi‐2D axisymmetrical field‐circuit methodology for electromagnetic device dynamics analysis has been elaborated. Proposed constructional solutions enable one to reduce the power losses in the primary core by half and total losses by 30 percent.