A detailed introduction to thin film capacitors(II)

Usually, thin film capacitors are made by using aluminum and other metal foil as electrodes and then winding them together. But there is also a method of making thin film capacitors, called metallized films, in which a thin layer of metal is evaporated on a plastic film as an electrode. This can save the thickness of the electrode foil, reduce the volume of capacitor unit capacity, so thin film capacitors are easier to make into small, large capacitors. Common MKP capacitors, for example, are synonymous with metallized polypropylene film capacitors, while MKT are synonymous with metallized poly (ethylene glycol) capacitors.

The films used in metallized thin film capacitors are polyethyllum, polypropylene, polycarbonate, and so on. In addition to the winding type, there are also stacked types. The metallized film capacitor of this type has a so-called self restoring effect, that is, if the tiny part of the electrode is short-circuited because of the weakness of the electrical boundary, it causes the metal of the electrode around the short-circuit part. Because of the electrostatic energy or short-circuit current of the capacitor at that time, it will cause a larger area of melting and evaporation and restore the insulation, so that the capacitor will return to the role of the capacitor.