The Leakage Current Analysis on 20 kV Suspension Porcelain Insulator Contaminated By Salt Moisture And Cement Dust in Padang Area

Suspension porcelain insulator plays an important part in Indonesian power system delivery. Most of the installed insulator consists of this kind of insulator especially in Sumatra in this case Padang 20 kV power distribution system. Due to the geographical position, which is located near to the shore and affected by local cement industrial dust, some insulator experiences with failed and cause the line interruption. To analyze this phenomenon, a research work was conducted to see how the both salty moisture and cement dust affect the insulator performance. During these research activities, mimic moisture system is developed to moisturizing the insulator during the experiment. Testing was done for three conditions. First is for clean insulator in dry and wet condition second is for salty moisture in dry and wet condition and the last is for cement dust in dry and wet condition. During the experiment, the leakage current data were noted according to the any condition and then analyzed. The analysis shows that, for equivalent salt deposit density (ESDD) 1.8times10^-3 mg/cm ² indicates that 0.89 mA leakage current in magnitude flows in with the total harmonic distortion (THD)=19.96 % and for ESDD 0.08 mg/cm² indicate 23.3 mA leakage current magnitude, THD=34.56 %. In conclusion, this research shows that the both salty moisture together with cement dust have a significant impact to the suspension insulator performance rather then the moisture alone or the cement dust alone