Effect of pulsed discharge current on lifetime performance of metallized polypropylene film capacitors

Metallized polypropylene film capacitors (MPPFCs) are the key components in pulsed power systems. The self-healing property guarantees MPPFCs' application under high electric fields. This paper mainly concentrates on the effect of the pulsed discharge current on the lifetime performance. The end connection peak current density (Id) and reversal coefficient (β) are two critical parameters which affect the lifetime. Experiments are designed to investigate the lifetime under different Id and β. The results indicate that the lifetime is sensitive to β. Empirically derived lifetime-scaling equation is given to predict the lifetime under different β. When Id is higher than 13 A/m, the electrode fracture might occur in the MPPFCs and the probability of the sudden capacitance drop will increase. Therefore, this phenomenon results in lifetime reduction.