Study on the characteristics of palm oil and it´s derivatives as liquid insulating materials

Insulation is one of the most important parts in a high voltage apparatus. Petroleum-based mineral oils have been used as insulation for power transformer since long time ago. Recently, peoples pay attention on the environmental aspects of the oils. Researchers are now searching new types of insulating materials, which are friendly to environment. We have investigated the dielectrics-short term characteristics of Palm Oil and its derivatives in attempt to find the environmental friendly insulating materials. The samples used including CPKO (Crude Palm Kernel Oil, CCO (Crude Coconut Oil, RCO (Refined Coconut Oil) and RBDPO (Refined, Bleached and Deodorized Palm Oil). The losses factors and breakdown voltages of the oils as function of temperature were investigated. The values of flash point, viscosity, specific heat and pour point are presented. The comparison of the properties of the oils with that of mineral and silicone oils is also done. According to the existing standard such as IEC, ASTM or British Standard, some of the oils such as RCO and RBDPO may be used as alternatives for liquid insulating materials in the future. However, long-term performances of the oils have to be investigated.