Effects of Fabrication Conditions on the Partial Discharge Mitigation Performance of Electrets for Power Electronic Driven Systems

In our previous studies, we have shown that electrets can be designed to mitigate partial discharge (PD) in power electronic converter (PEC)-driven systems by neutralizing locally enhanced harmful electric fields. Surface charge density is one of the main factors that determines the PD mitigation performance of electrets. In this study, we fabricate electrets from polyvinylidene fluoride films under various charging conditions including voltage magnitude, charging duration, voltage polarity, and temperature using triode-corona discharge method. The surface charge density and PD mitigation performance of the fabricated electret films are assessed by surface potential measurements and PD experiments. The effects of fabrication temperature on electret surface charge stability, and the impacts of atmospheric conditions on electret surface charge density and PD magnitude are discussed. This study provides knowledge that is essential for establishing the fabrication conditions of electrets that can effectively mitigate PD in PEC-driven systems.