STUDI ANALISIS GANGGUAN TRANSFORMATOR DISTRIBUSI PADA JARINGAN DISTRIBUSI 20 KV Di PT. PLN (Persero) Distribusi Jawa Barat dan Banten Area Pelayanan dan Jaringan (APJ) Karawang KARAWANG � JAWA BARAT

Distribution transformer is the heart of the power distribution network of 20 kV. Distribution transformers are expected to work continuously to supply electricity to customers. Interference with the distribution transformer resulting in damage to the transformer and the electrical power supply interruption to customers. Disturbances in the distribution transformer can be caused by the occurrence of an external short circuit, failure of isolation, due to lightning, protection failure, tap changer weakness, lack of maintenance, operational errors, the process of aging, damage or packing leaks, leaks in the bushing and other cause of disorders. A case study on 20 kV distribution network in PT . PLN ( Persero ) Karawang, during the first half of 2013, indicating a high disturbance occurs in distribution transformers. Disorders due to short circuit 6.25 %, due to insulation failure 31.25 %, 37.5 % due to lightning, because of protection failure 4.17 %, due to lack of maintenance 2.08 %, 4.17 % due to operational errors, because of the process aging 10.42 %, 2.08 % due to leakage bushing and 2.08 % from other causes. It is seen that the most disorders are due to lightning, as many as 37.5 %