Static electrification properties of transformer oil

Abstract

In recent years much attention has been given to oil flow in power transformers with cellulosic insulation, due to the failure of some field units from discharges resulting from charge accumulation. Charge separation is a function of several factors: nature of oil, flow velocity, type of solid insulation, surface conditions, duct space, insulation geometry, temperature, and the presence of ionic impurities and charge producing species in the oil. This paper focuses on the role of transformer oil in the charge separation process.