The Effect of Voltage Polarity Reversal on Space Charge Behavior of Epoxy MgO Nanocomposites

In the present study, the epoxy nanocomposites with different weight percentage of MgO nano filler were prepared. The accumulation of space charge within the bulk of the insulation would distort electric field distribution under polarity reversal voltage condition. In the present study, pulsed electro acoustic (PEA) method was adopted for space charge measurement. The space charge density and electric field were measured during both poling periods. The accumulated space charge cannot dissipate immediately after the polarity reversal, which aids the redistribution of the electric field with in the specimen. The addition of MgO nanoparticles showed suppressed space charge accumulation and reduced the electric field distortion during polarity reversal with 1, 3 and 5 wt% MgO filled epoxy nanocomposites.