Mechanism Analysis of Capacitor Failure(I)

     Effect of moisture on deterioration of Electrical parameters

    When the humidity in the air is too high, the water film is condensed on the surface of the capacitor shell, which can reduce the surface insulation resistance of the capacitor. Here, for a semi-sealed structure capacitor, moisture can also penetrate into the capacitor medium, so as to reduce the insulation resistance insulation ability of the capacitor dielectric.Therefore, the effects of high temperature and high humidity on the deterioration of capacitor parameters are very significant. The electrical properties of capacitors can be improved after drying and dehumidifying, but the consequence of water molecule electrolysis cannot be eradicated.For example, when capacitors work at high temperature, water molecules are electrolyzed to H + + and OH-O + + under the effect of electric field, and electrochemical corrosion occurs at the root of the lead. Even when drying and dehumidifying, it is not possible to restore the lead.