Molecular Insights into the Effects of Voltage Ramp Rate on the Self-Healing Properties of Metallized Film Capacitors

Metalized film capacitors(MFCs), with the high energy density and low loss characteristics, have become core energy storage components in fields like new energy gridconnected inverters and pulsed power devices. As the most important feature of MFCs, self-healing enhances the voltage withstand capability and operational reliability of devices. But there is still a lack of systematic theoretical explanation for the microscopic mechanism of the electric field parameters on the self-healing process. In this study, we analyzed the self-healing properties of MFCs under different voltage ramp rate. Combined with density functional theory(DFT), the reasons for the difference in self-healing properties of MFCs were further analyzed, and the relationship between the change of microscopic properties and macroscopic self-healing properties was also established. These findings will be helpful to better understand and regulate the self-healing properties of MFCs.