What is the difference between the functions of thin film capacitors in different circuits?

Thin film capacitor is a capacitor made of metal foil as electrodes and plastic film such as polyethyl ester, polypropylene or polystyrene which are wound sensitively or sensitively after overlapping from both ends. It is also known as a plastic film capacitor because it is made from plastic films such as polyethyl ester, polypropylene or polystyrene as dielectric.

Because of its high insulation impedance, good frequency characteristics, no polarity and small dielectric loss, thin film capacitors are used in many industries such as electronics, household appliances, communications, power, etc. They are also used in high frequency filtering, high frequency bypass, analog circuits. So what role does the film capacitance play in different circuits?

(1) Parallel thin-film capacitors, also known as moving thin-film capacitors, are mainly used to compensate the reactive power of the inductive load of the power system, to improve the power factor, to improve the voltage quality, and to reduce line loss in the circuit.

(2) Series thin-film capacitors, which are connected in series in power frequency and high voltage transmission and distribution lines, are used to compensate the distributed reactance of the lines, improve the static and dynamic stability of the system, improve the voltage quality of the lines, greatly increase the transmission distance and improve the transmission power.

(3) Electric heat film capacitor, used in the system of electric heating equipment with frequencies between 40 and 24000 Hz, to improve the power factor and the voltage or frequency of the circuit.

(4) Coupled film capacitors are mainly used for high frequency communication, measurement, control and protection of high voltage power lines.

(5) Circuit breaker film capacitor, formerly called piezoelectric equalizing capacitor, plays a role of equalizing voltage on the breaks of high voltage circuit breakers by parallel connection, so that the voltage between the breaks of high voltage circuit breakers is even during the process of segmentation and disconnection, which can improve the ARC-BREAKING characteristics of circuit breakers and enhance the breaking capacity.