What is the principle of insulator

The principle of insulators is that their internal molecular structure tightly binds positive and negative charges, thereby limiting the number of freely moving charged particles. These charged particles are mainly electrons or ions, which are not easy to move freely under normal circumstances, so the resistivity of the insulator is very large, usually above 10^7 ohm·meter.

This means that under normal conditions, insulators are insensitive to the effects of external electric fields and do not form macroscopic currents, so they can be considered non-conductive substances.

However, under the action of a strong electric field, the charges inside the insulator may break free and form free charges. This phenomenon is called dielectric breakdown, and the performance of the insulator will be destroyed.

In an insulator, even under the action of an external electric field, charges will undergo microscopic displacement and produce polarized charges, which is a manifestation of dielectric polarization.The polarization mechanism of insulators can be divided into two types: non-polar molecules and polar molecules.