The Study On The Development Process And Rule Of Oil Wedge Discharge In Transformer

Partial discharge can be used to evaluate insulating condition.To solve the problem that how to identify the process and rules of oil wedge discharge(PD),the thesis established a model of transformer PD with controlling temperature for testing.Simulation of transformer inner oil wedge discharge used sphere-disk electrode model while studying the process and rules of PD at different voltage level.The partial discharge signals were gathered by a united detective system of UWB method,pulse current method and UHF method.The results indicated that the PD signals had different trends at different voltage level.Besides,the average amplitude,the maximum amplitude,the times of discharges,the average pulse rise time,the average pulse width and the pulse total energy were all can be parameters for researching the development process of partial discharge.The development process of wedgeshaped partial discharge could be divided into two stages in according to the development process analysis.The researches laid the foundation for solving the problem that how to identify the severity grade of partial discharge in PD detection.