Multi-objective optimization of electromagnetic fields from urban overhead power lines

This work presents a multi-objective and multicriteria optimization methodology of low frequency electromagnetic fields for urban overhead power line projects. The mathematical modeling considers the conductors as catenaries, and the optimization objectives are the electric and the magnetic field at the ground level, as the structure cost index. The formulation considers predefined limits to mechanical strains caused by the wind and its influence over conductors and insulators, land use and electromagnetic field limits. The results obtained by applying the Non Dominated Genetic Algorithm (NSGA-II) are ranked by the technique of Analytic Hierarchy Process (AHP) with its parameters set by the designer to choose the most appropriate solutions for the detailed engineering phase and subsequent implementation. Simulations were performed under the environmental conditions and legislations of five countries in an urban area case study. The results show that the compaction of the phase-to-phase distance and the choice of the correct conductors help to reduce the right of way and the electromagnetic emission and also reduce the transmission tower's height, consequently decreasing the global project cost.