BFC237022334

Due to market price fluctuations, if you need to purchase or consult the price. You can contact us or emial to us:   sales@allicdata.com

BFC237022334 Application Field and Working Principle

Film capacitors, or film dielectric capacitors, are capacitors with a dielectric material that is composed of a thin plastic film. These dielectric materials are usually polyester (PET), polypropylene (PP), or nylon (PA). They are named film capacitors due to the use of a thin plastic film as the dielectric material. Film capacitors can be divided into three types by dielectric material: polyester film capacitors, polypropylene film capacitors, and high-voltage film capacitors. Applications for these capacitors include analog and digital circuits, signal processing, power supply smoothing, filter systems, and motor start-up.

Working Principle of Film Capacitors

Film capacitors are based on the principle of electrostatic induction. A three-layer structure is utilized in the design of the capacitor, consisting of two metal plates, and a dielectric film in between. The two metal plates act as the electrodes that create an electric field that affects the electrons of the dielectric film, resulting in the formation of electric dipoles. These electric dipoles then interact with one another, resulting in an increase in the capacitance of the capacitor.

As the applied voltage increases, the electric field between the metal plates and the dielectric film increases. This electric field, along with the increased polarizability of the film, leads to an increase in capacitance. As the electric field strengthens, the size of the dipoles increases, resulting in an increase in the capacitance of the capacitor. A similar effect is seen when AC signals are applied to the capacitor, as the changing electric field\'s associated with the AC signals cause the size of the dipoles to vary, leading to varying levels of capacitance.

Advantages of Film Capacitors

Film capacitors offer several advantages compared to other forms of capacitors. They are highly resistant to climatic influences, reliably exhibiting low capacitance change and low insulation resistance even in high humidity. Some of these capacitors are rated for use up to 125°C, making them suitable for use in high-temperature applications. Film capacitors can also be constructed to have a very high dielectric strength, making them ideal for applications that require high voltage protection.

Applications of Film Capacitors

Film capacitors find use in a variety of applications, such as power supply smoothing, filter systems, motor start-up, signal processing, and analog and digital circuits. They are particularly suitable for high-frequency and high-voltage applications, where their superior dielectric properties provide increased safety and reliability. In addition, film capacitors are suitable for use in hostile environments and for applications that require extremely small sizes. Film capacitors are used widely in motor start and other applications that require frequent switching in low-voltage circuits.

Conclusion

Film capacitors are used in a variety of applications, such as power supply smoothing, filter systems, motor start-up, signal processing, and analog and digital circuits. They provide a number of advantages, such as increased reliability, robustness, and superior dielectric properties compared to other capacitor types. Film capacitors are particularly suitable for use in hostile environments and for applications that require small sizes.

The specific data is subject to PDF, and the above content is for reference