The Effect of Resistive Leakage Current on The Reliability of Lighting Arrester in PLN UPT Bogor Area

Abstract

The biggest cause of transmission disruptions in the Bogor Technical Implementation Unit (UPT) working area is natural disturbances caused by lightning. Lightning arresters (LA) are substation equipment that function as safety devices for installations from overvoltage disturbances caused by lightning strikes (lightning surges) and switching surges. LA are installed to cut off surge voltages by diverting surge currents to the ground. Given the critical role of LA, corrective maintenance is necessary to ensure their reliability. The test commonly performed is the measurement of resistive leakage current in the LA. The purpose is to determine the condition of the LA, whether it is still in good condition or not. Factors that affect the results of leakage current measurements are the position of the field probe, fluctuations in the arrester voltage level, and the influence of ambient temperature and humidity. The LA in the UPT Bogor system currently uses arresters with technology that utilises gapless Metal Oxide blocks, better known as MOSA (Metal Oxide Surge Arrester) type. This thesis discusses the impact of damage based on the analysis of Resistive Leakage Current Measurements of MOSA Type Lightning Arresters.