Use of Rod Compactors for High Voltage Overhead Power Lines Magnetic Field Mitigation

Abstract

Abstract:In the last decades, strengthening the high voltage transmission system through the installation of new overhead power lines has become critical, especially in highly developed areas. Present laws concerning the human exposure to electric and magnetic fields introduce constraints to be considered in both new line construction and existing systems. In the paper, a technique for passive magnetic field mitigation in areas close to overhead power lines is introduced, fully modelled and discussed through a parametric analysis. The investigated solution, which basically consists in approaching line conductors along the span making use of rod insulators, is applicable on both existing and under-design overhead lines as an alternative to other mitigating actions. Making use of a 3-dimensional representation, the procedure computes both positions of phase conductors and forces acting on insulators, towers, conductors and compactors, with the aim of evaluating the additional mechanical stress introduced by the compactors. Finally, a real case study is reported to demonstrate and quantify the benefits in terms of ground magnetic field reduction achievable by applying the proposed solution, in comparison to a traditional configuration. Furthermore, using compactors to passively reduce the magnetic field is simple to be applied, minimally invasive and quite inexpensive as regards to alternative mitigating actions.

The Influence of the Mixed Electric Line Poles on the Distribution of Magnetic Field

“…In many rural and suburban areas, in order to distribute electricity more economically, electricity is distributed using mixed overhead lines [5]. The World Health Organization (WHO) is making significant efforts and resources to establish a causal link between the effects of electromagnetic (EM) fields and potential diseases in people living or permanently residing in areas around power plants [6].…”

A Survey on Optimization Techniques Applied to Magnetic Field Mitigation in Power Systems

“…A further MF reduction can be obtained by reducing the phase-to-phase clearance (compaction). For example, by installing compactors along overhead line spans (realized through rod insulators forming equilateral triangles), a 56% reduction of the maximum ground-level MF is achievable, in comparison to an overhead transmission line realized with compacted towers (the solution that, at present, minimizes the magnetic field without compactors) [14]. However, this solution also entails a new problem, which includes higher voltage gradients on conductors and insulators, resulting in higher audible noise, radio interference, and increased hardware corona [15][16][17][18].…”

“…overhead transmission line realized with compacted towers (the solution that, at present, minimizes the magnetic field without compactors) [14]. However, this solution also entails a new problem, which includes higher voltage gradients on conductors and insulators, resulting in higher audible noise, radio interference, and increased hardware corona [15][16][17][18].…”