Effects of oil palm empty fruit bunch filler on electrical tree propagation in Epoxy resin

Epoxy resin is a kind of polymer which has advantages such as good thermal characteristics, excellent adhesion, good water repellent and resistance to pollution. During operation, field enhancement sites such as in void and protrusion may exist within the polymeric insulation. Degradation of the insulation may start from these parts and electrical treeing will grow. The appearance of an electrical treeing is a sign of degradation that develops in insulation. In view of this there have been numerous studies on various types of fillers which serve as treeing retardants. This paper presents investigation on the effect of a new organic filler, Oil Palm Empty Fruit Bunch (OPEFB), on the electrical tree propagation in Epoxy resin It was found that the tree propagation time for the sample containing 1 wt % OPEFB was 50 minutes with tree length of 0.64 mm while the non-filled sample exhibited a tree length of 1.7 mm at 30 minutes implying the tree length of filled sample was shorter than tree length of non-filled sample and the tree propagation time for filled sample was longer than non-filled sample. It was also observed that the electrical tree in filled sample appeared in the form of bush-type tree whereas electrical tree in non-filled sample grew in a straight manner in the form of branch-type tree. This finding suggests that the OPEFB used in this study as organic filler has helped to slow down the tree propagation time and increased the insulation lifetime.