Study on Factors Influencing Self-healing Energy of Metallized Film Capacitors

Metallized film capacitors are widely used as low-voltage reactive power compensation devices in power systems. However, frequent self-healing breakdown seriously affects the insulation performance and life of capacitors. In order to study the self-healing characteristics of metallized film capacitors, an experimental platform was established to study the effects of voltage, temperature, shunt capacitance, film thickness, and interlayer pressure on the self-healing energy of metallized film capacitors. The results show that, the self-healing energy increases by 58.59% with increasing voltage in the range of 950–1150 V; in the range of 30–90 °C, the self-healing energy decreases by 36.08% with increasing temperature; in the range of 10–160 μF, the parallel capacitance has little effect on the self-healing energy; in the range of 6–10 μm, the self-healing energy increases by 246% with increasing film thickness and in the range of 20–800 kPa, the self-healing energy decreases by 47.11% with the increase of interlayer pressure. The results of the study can provide guidance for the optimal design of metalized film capacitors.