Dry DC metallized film capacitor exhibits special “self-healing” properties

allowing the elimination of electrical vulnerabilities through an “empowering” process prior to operation. Compared to foil capacitor

it offers higher operational voltages and greater energy storage density. For this purpose

the in-situ test platform of self-healing properties of metallized film is set up

the evolution of the self-healing of metallized film under the AC/DC superposition is studied

and the mechanism of different AC/DC composite voltage to the self-healing properties of metallized film is analyzed under the action of such stresses as temperature and pressure. At the same time

based on observed phenomena and derived conclusions from temperature experiments

a thermodynamic model for self-healing is set up. It is defined from the point of view of thermodynamic theory that the joule heating is the primary source of self-healing energy. It is found through simulation and calculation that the thermodynamic model exhibits very good fitting effect at low itensity of pressure (0.1 MPa)

but shows notable error at high intensity of pressure (10 MPa).