As two items of electronic components that are widely used in electronic equipment, capacitors and electrolytic capacitors are widely used in the circuit of direct alternating, coupling, bypass, filtering, tuning loop, and play a pivotal role. What are the differences between the functions of capacitors and power capacitors?

Capacitor: 'electrically charged vessel', a device that holds electrical charge. It is composed of two metal electrodes sandwiching a layer of insulating dielectric. When a voltage is applied between two metal electrodes, a charge is stored on the electrodes, so a capacitor is an energy storage element. Any two conductors that are insulated and close to each other form a capacitor. The parallel plate capacitor consists of the electrode plate of the capacitor and the dielectric.

Power capacitors: Capacitors used in power systems and electrical equipment. Is a kind of capacitor, metal foil for the positive electrode (aluminum or tantalum), and the positive electrode close to the metal oxide film (aluminum oxide or tantalum penoxide) is the dielectric, the cathode is composed of conductive materials, electrolyte (electrolyte can be liquid or solid) and other materials, because the electrolyte is the main part of the cathode, electrolytic capacitor so named. At the same time, the electrolytic capacitor can not be connected to the wrong.

The role of a capacitor can be graphically described by a water tower connected to a water pipe. The water tower is used to "store" water pressure - when the water supply system pumps supply more water than the town needs, the excess water is stored in the water tower. Then, when the water demand is high, the excess water will flow out of the water tower to maintain the water pressure. The capacitor stores electrons in the same way and can release them later.

Shunt capacitor is a kind of reactive power compensation device. Usually (centralized compensation type) is connected to the low voltage bus of the substation, its main role is to compensate the reactive power of the system, improve the power factor, thereby reducing the energy loss, improve the voltage quality and equipment utilization. It is often used with on-load voltage regulating transformer.

The above is the difference between the function of capacitors and power capacitors.