A Study on Varies Temperature and Varies Gap Distance on Mixed Vegetable Oil as a Transformer Oil

Natural ester oil is one of the alternative materials that can be used to increase the supply of transformer oil. This research discloses the investigation of breakdown voltage of mixed oil virgin coconut oil (VCO) with refined, bleached and deodorized palm kernel oil (RBDPKO) under the effect of different temperature and different gap distance. The test was organized based on the guideline in IEC 60156 standard for AC supply under uniform field (sphere-sphere). The ratio of mixed oils in this experiment are 0% VCO, 20% VCO, 40% VCO, 60% VCO, 80% VCO and 100% VCO. The result indicates that, the ratio of 20% VCO was the highest breakdown voltage for mixed oil at different temperature which was 48.7 kV (40°C) and 57.9 kV (80°C). The increasing of the temperature and the distance gap gave impact on the breakdown strength.