At present it is claimed that all electrical energy systems operate with high values of efficiency and reliability. In electric power systems (EPS), electrical power and distribution transformers are responsible for transferring the electrical energy from power stations up to the load centers. Consequently, it is mandatory to design transformers that possess the highest efficiency and reliability possible. Considerable power losses and hotspots may exist in the bushing region of a transformer, where conductors pass through the tank. Most transformer tanks are made of low-carbon steel, for economical reasons, causing the induction of high eddy currents in the bushing regions. Using a non-magnetic insert in the transformer tank can reduce the eddy currents in the region and as a consequence avoid overheating. In this work, analytical formulations were developed to calculate the magnetic field distribution and the stray losses in the transformer region where bushings are mounted, considering a stainless steel insert (SSI) in the transformer tank. Previously, this problem had only been tackled with numerical models. Several cases were analyzed considering different non-magnetic insert sizes. Additionally, a numerical study using a two dimensional (2D) finite element (FE) axisymmetric model was carried out in order to validate the analytical results. The solved cases show a great concordance between models, obtaining relative errors between the solutions of less than two percent.

A finite-element formulation in terms of the magnetic field intensity is developed for 2-D eddy current problems, such that the current density lies in a plane, whereas the magnetic field is normal to such a plane. This type of configuration arises in the analysis of nondestructive testing of pipes, evaluation of transformer tank wall losses, and other applications. By conserving the displacement current, even for low-frequency cases, multiply connected domains and regions with very low conductivity are easily handled. Procedures for loss evaluation, mesh adaptation, and consideration of ferromagnetic materials have been developed.

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Fundamental parts of an electrical system are radial systems, which may be operating at different voltage levels, where an unwanted event such as ferroresonance is possible to occur. The conditions for the presence of a ferroresonance in an electrical system can present high overvoltages that can result in damage to critical equipment, high costs of corrective maintenance and plant shutdowns. These impacts mentioned justify the importance of analyzing, predicting and being able to establish strategies that avoid ferroresonance. In the present work simulations of radial feeders are shown where the ferroresonance event is presented as well as strategies to mitigate it by observing the behavior of voltage signals through simulations in the ATPDraw software.

Computational electromagnetism spans a wide variety of techniques for the solution of Maxwell's equations. Some applications of such methods to the solution of problems arising in electric power engineering are reviewed in this paper, drawing from the experience accumulated in the development of a finite element code with modules for electrostatic, magnetostatic and magnetodynamic (eddy current) cases.

A finite element formulation in terms of the magnetic field intensity is developed for two-dimensional eddy current problems, such that the current density lies in a plane whereas the magnetic field is normal to such plane. This type of configuration arises in the analysis of nondestructive testing of pipes, evaluation of transformer tank wall losses and other applications. By conserving the displacement current, even for low frequency cases, multiply-connected domains and regions with very low conductivity are easily handled.