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Electromagnetic field problems arising in electrical machinery and devices are in general truly three dimensional in nature. In many devices natural excitation is the voltage excitation, for example: relays and electrical motor. Several research papers have been published on the subject of three dimensional field solutions. Many different formulations of the 3D electromagnetic problems are possible. They involve differential or integral formulations in terms of scalar or vector unknowns. The aim of this paper is to present a method capable of solving general 3D eddy currents with voltage excitation in nonlinear magnetic field using the A, A‐V formulation. The method of the finite difference equations formulation based on minimising of the energy functional has been given.

Presents 3D method for the computation of the winding current distribution and power losses of the electromagnetic gear. For a prescribed current obtained from measurement, the transient eddy current field is defined in terms of a magnetic vector potential and an electric scalar potential. From numerically obtained potentials the power losses are determined. The winding power losses calculation of an electromagnetic gear shows that a given course of the current generates skin effect and significantly changes the windings resistances. Also presents the designing method for reducing power losses.

To present modelling and control technique of an electromagnetic actuator.

A 3D modelling technique of voltage‐forced electromechanical actuator takes into account: motion, magnetic non‐linearity and eddy current phenomena. Control problem of closed loop system is described by coupled electro‐magneto‐mechanical equations and non‐linear PID controller equations.

Presented methodology offers a powerful tool for analysis of control systems with distributed parameters models and may contribute to the improvement of the electromechanical performance of electrodynamic devices.

As original contribution a position feedback control using conventional PID controller is applied for iterative determining inverse dynamic problem, that is finding input voltage for a given position of an actuator.

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.