Lightning current field measurement on a transmission line , comparison with electromagnetic transient calculations

A lightning experiment is conducted on the 123 kV single-circuit transmission line Ston – Komolac located in the area of Dubrovnik (Croatia), which has a very high lightning ground flash density. This line is equipped with ga pless line arresters. This experiment has been operational for 6 years and presently includes, after several upgrades, the fol l wing elements: On two towers the shape of the transient currents circulating through the 3 line surge arresters are measured with Pearson’s sensors; in addition a specially develope d Rogowski coil has been installed around both towers to measu re the lightning current circulating through them. These sensors are connected to a real time monitoring system, energiz ed by a solar panel, with a communication system making use of a mobile phone network to transmit the measurement data to a remote server, in order to avoid the burden of on-site vis its to get the measurements. This monitoring system had been prese nt d in previous papers [1][2]. At the line remote end subs tations some Rogowski coils measure the lightning current through the station arresters, and measurements of currents and voltage at the secondary side of the measuring transformers are ma de too. All the lightning measurements are compared with the data obtained from the lightning detection system coveri ng Croatia (LINET). It was shown that the consistency of these 2 sources of information is quite satisfactory. Since the beginning of the experiment many measurem ents have been obtained, some of them corresponding to v ery strong lightning strokes. In this paper we are presenting examples of measurements, some statistics of the transient curr ents circulating through the line arresters and some comparisons between measurements and EMTP-like calculations.