@thesis{thesis, author={Sirait Yoko Delfierro and Soewono Soetjipto}, title ={ANALISIS TERJADINYA BACKFLASHOVER PENGARUH PENTANAHAN PADA MENARA SALURAN UDARA TEGANGAN TINGGI 150 KV GI DURIKOSAMBI-GI PANTAI INDAH KAPUK}, year={2018}, url={http://156.67.221.169/693/}, abstract={On overhead transmission line, fault often occur caused by lightning strike. One kind of fault is an occurrence of backflashover. Backflashover phenomenon is caused by a direct strike to the ground line and the tower which later affects resistance of the isolator. Backflashover happens when voltage emerging on the isolator is greater or the same as isolatorcritical arcingvoltage. The factor causing the later is high earthing value of the tower base making lightning surge current to be channeled to the ground. in this paper, the occurence of backflashover will be analyzed regarding how backflashover happens from the effect of the tower base grounding using quantitative method. As for the calculation, it is done on 19 towers along the transmission line. There are three towers on which have the potential of backflashover to happen, those three are towers number 27, 30, 32, whose isolator voltage value exceed critical arcing voltage (V50%=1233,23 kV). Tower 27 amounts to 1246,333 kV (2,34?), tower 30amounts to 1621,192 kV (4,93?) andtower 32amounts to 1662,362 kV (5,4?). So then, the high tower base grounding value may result in backflashover. And for the backarcing probability on grounding value of 5,4? is at 0,0276 and for0,1? is at 0,00838. So, the probability of back arcing is lowered when ground resistance value is decreasing.} }