Tests on self-healing metallized polypropylene capacitors for power applications

Results of research carried out at the Institute of Industrial Electrical Engineering of the University of Bologna on self-healing metallized polypropylene (MPP) power capacitors are presented. The aim of the tests is to characterize the degradation of these capacitors when employed in automatic power factor correction systems or in power electronic applications with special reference to the disconnection of the `sprayed ends´ from the electrode-edges, one of the main reasons for failure of MPP capacitors employed in the above systems. The research is carried out also in view of the definition of adequate type-test standards, presently not yet available for this kind of application