Improvement of Lightning Protection System for Transmission and Distribution Lines in High Lightning Density Area

Transmission and Distribution lines of an oil company play an important role to supply power to the pumping station at the wide area in central Sumatra. The operational area of this oil company located along the equator line and has a very high lightning density. The failure of the supply power due to lightning strikes caused high loss of daily oil production. Research on lightning detection system improvement was carried out at Sumatera Oil Company. Lightning characteristic data for the evaluation and improvement of the lightning performance of the distribution lines were derived from this Indonesian Lightning Detection Network called Jaringan Deteksi Petir Nasional (Jadpen) using Time of Arrival Technology called TOA system. Jadpen is supported with 5 sensors. The improvement of overhead lines lightning performance was carried out in two ways; one is conventional way, and the other is free standing mast (FSM) with extended mast at the existing high structure known as extended mast terminal (EMT). It is an improvement lightning protection system which is installed at the tower top equipped with air terminal connected to the grounding system using double insulated down conductor cable. This arrangement prevents the ground wire and poles being hit directly by lightning. No line parameters will be "read" by the lightning current and back flashover and shielding failures on the line will be minimized. The use of data derived from lightning detection network is helpfull to determine the suitable location for FSM and EMT installation.