Working principle of film capacitor in AC circuit(I)

With the development of science and technology and the advantages of film capacitors instead of electrolytic capacitors, the frequency of using thin-film capacitors is higher and higher. Today, Xiaobian will share with you the principles of thin film capacitors in AC circuits. In middle school, there is a saying that goes through the exchange, blocking DC, that is, the nature of capacitance. In DC circuits, film capacitors are equivalent to circuit breakers.

We can start with the structure of the film capacitor. The simplest capacitance is made of insulating dielectric. After electrification, the polar plate is electrified to form a voltage (potential difference), but the intermediate is not conductive because of the insulating substance. However, this situation is not in excess of the critical voltage (breakdown voltage) of the capacitor.