The Effect Of Power Transformer Oil Temperature Rises On Potential Distribution In Transformer Windings Under The VFTO

Multi-conductor Transmission Line (MTL) model based on the representation of the windings by its individual turns is used to analyze the transient response of transformer windings under Very Fast Transient Over-voltage (VFTO).In this paper we get the permittivity of transformer oil through the experiment under the different temperature. A very efficient method, the simplified finite element method is used to compute the elementary capacitance parameters of transformer windings. By the capacitance parameters we compute the inductance, conductance and resistance parameters of transformer windings under the different temperature. In this paper we get the potential distribution in transformer windings under the different temperature. Thus we obtain the effects of power transformer oil temperature rises on potential distribution in transformer windings under the very fast transient over-voltage. In order to facilitate the engineer designers, this paper also study the simple wave of VFTO input waveform. For validation, the calculated results are compared with the quondam results on a transformer winding model and the result is satisfactory.