Electromechanical dynamics of overhead electric power line conductors analysed through the Modelica language models

In the last years the use of high temperature low sag conductors has become more and more frequent in electric power system. Such conductors have an inner layer in polymeric and/or fibre material, with reduced thermal coefficient and weight with respect to conventional ones. For this reason, under short circuit conditions they can experience large displacements due to the electromagnetic forces induced by the fault currents. Such displacements can influence phase-to-ground or phase-to-phase clearances, thus reducing the system security. In this paper, a possible way to model the dynamic electromechanical behaviour of overhead electric power lines conductors is presented and discussed, using lumped parameter models implemented through Modelica language.