Corona discharge within organic oil insulations

Presented experiment consists of laboratory testing of partial discharges activity in liquid insulating fluids. Corona discharges within different insulation fluids were measured accordingly. The trends of partial discharge main parameters are studied and described in dependence on liquid type and aging time. The studied oils were thermally aged at 90°C for 3000 hours in air atmosphere within special climatic oven. Corona discharges measurement was realized using a point/plane electrode configuration where the whole test set-up was completely immersed in tested oil to suppress ambient conditions.