Lightning Protection System for High Voltage Transmission Line in Indonesia

Based on the outage data released by Indonesia Electricity Company (PLN), the line-outages occurred at trnasmission line in Indonesia is very high, 49% occured at 150 kV line and almost 69% in 70 kV lines all over Indonesia. This reserch was carried out at 70kV transmission line in Malang, an area located at south part of east Java, Indonesia which is mostly suffered due to lightning strikes. Transmission towers in this arew were being the easy target of lightning strikes due to their height of more than 30 meter, have only one erth wire and most of them are located on the open area. Lightning strikes to towers produced back flashover on the insulator and lead to the blackouts on the system. This research analyzes the performance of the 70kV high voltage transmission line against lightning strikes based on installed lightning protection devices. A protedction system is introduced to improve the performance of the transmission line against lightning strikes by installing Extended Mast Terminal (EMT) on the transmission tower. EMT is a lightning protection system equipped with Early Streamer Emission (ESE) as an Air Terminal to attract the lightning strikes, low inductance lightning down conductors, integrated grounding system and a panel at the bottom of the cable to record the number of lightning strikes and the peak current of lightnuing detector.