Effect of magnetic field on electrical treeing behavior in silicone rubber under low temperature

This paper presents the study of the relationship between magnetic field (MF) and growth mechanism of electrical tree in silicone rubber (SiR) under low temperature. Needle-plate electrode was employed in this paper to generate electrical tree, and silver needle was employed to avoid stress generated by the MF. Samples were applied pulse voltage of +12 kV. 0 and 400 mT magnetic field density was applied, respectively. The MF was perpendicular to the electric field direction. The morphology of the tree was captured by a digital microscope. The tree length and the accumulated damage were measured. It is observed that the MF promotes the increase of accumulated damage, while the MF inhibits the growing of tree length after 60 minutes. It is suggested that partial discharge activity within the tree channels is affected by the Lorentz force, the treeing behavior will be different as a result.