Understanding inception and propagation of electrical tree discharge characteristics in xlpe nano-composites

Failure of underground cables due to electrical treeing phenomena in the polymeric insulating material is a major threat for the safe and reliable operation of power system network. Hence many research works are being carried out in the development of high performance insulating materials for underground cables. Nano-composites are emerging as a new class of insulating materials for demanding application in all electrical equipment used in the electric power network. Both electrical and thermal properties are improved with the addition of nano fillers in the polymeric materials. In this work, the electrical tree inception and propagation were studied in the cable insulation material at different nano filler concentrations. SiO2 nano-filler was used in the XLPE base material. Nano-fillers were added at different concentrations such as 1% and 3% by weight in the base material. Laboratory experiments were conducted as per IEC procedures at AC voltage magnitudes of 12 kV. Influence of filler concentration on the inception and propagation of electrical treeing were studied. Analysis of time to failure of XLPE materials at different nano-filler concentrations were carried out.