Influence of Infeed Current and Double Circuit Transmission Lines in Distance Protection

Detailed analysis of influence of infeed current and double circuit transmission lines in distance relays is presented in this work. In addition, is investigate the teleprotection scheme that allows the rapid and accurate fault extinction best suited for the system addressed with these complex topologies. The modeling stages of the test system and coordination studies of protection were carried out in commercial software designed to simulate protection studies of power electrical systems, where multiple fault scenarios have been applied, considering influence of infeed current and double circuit transmission lines separately. The results revealed the presence of inaccuracies in the apparent impedance measurements, which should be considered when planning distance protection zones in complex power grid topologies. Furthermore, permissive overreach transfer trip teleprotection scheme proved to be more efficient in relation to the directional comparison blocking teleprotection scheme, since the former lead more accurate and faster faults extinction for the scenarios under study.