The cause of the breakdown of the capacitor

The concept of Capacitor Breakdown

The electric field strength of capacitance dielectric is limited. When the bound charge is separated from the atom or molecule to take part in the electric conduction, the insulation property is destroyed. This phenomenon is called dielectric breakdown.

The reason of Capacitor Breakdown

The fundamental reason of capacitor breakdown is that its dielectric insulation is destroyed, which leads to polarization. The reasons for the breakdown of dielectric insulation are:

(1) the working voltage exceeds the voltage of the capacitor;

(2) the quality of the capacitor is not good, the leakage current is large, the temperature is rising gradually, and the insulation strength is decreasing;

3 the capacitor is connected or connected to the AC power supply.

Methods of avoiding dielectric breakdown

adopt materials with high insulation strength;

Insulation material has a certain thickness, and does not contain impurity, such as bubble or moisture;

 try to distribute the electric field according to the requirement and avoid the power line being too dense in some places.

Can recover after breakdown

（1 ）dielectric is gas or liquid, are self-recovery insulating medium, breakdown reversible;

（2 ）dielectric is a solid, breakdown irreversibly, is the only breakdown after the insulation can not be restored.