Uprating an overhead line. Italian TSO applications to increase system N-1 security

Abstract

This paper analyzes innovative devices to optimize the energy flows transmission on existing overhead lines. Indeed sometimes the structural asset isn’t adequate to manage energy generated by Renewable Energy Source (RES) in particular operating conditions. In addiction the outage of primary substations on the grid and the increase of consumptions have caused growing load currents. In order to satisfy these needs, TSOs have adopted new measures on existing power lines and N-1 criteria to ensures the electrical grid security. These particular devices are Dynamic Rating systems. After introducing thermal resistant conductors and Dynamic Rating (DR) solutions, paper reports two different applications used by TERNA Italian TSO. These systems are already installed on lines and they are contributing to increase power flows thanks to raise by 10-30% of the real time dynamic ratings than the static evaluations. Advantages for electrical systems are many such energy vectors optimizations, congestions reductions, reliability increasing, cross-border power flows increasing, smart grid development.