Tag: shunt capacitor

We often hear shunt capacitors and series capacitors in circuit devices. So what is the difference between them? Today, we will introduce the differences between series capacitors and shunt capacitors.

A series capacitor is a reactive power compensation device. Usually series capacitors are used in EHV lines of 330kV and above. Its main function is to improve the system voltage from the perspective of compensating reactance, so as to reduce the power loss and improve the stability of the system. Capacitors must be able to withstand external forces due to short circuits, wind, snow and earthquakes. These mechanical forces are calculated through precise component analysis.

For wirings of three phase shunt capacitors or three phase capacitor banks composed of three single phase shunt capacitors, the most commonly used are star and triangle wirings. Star wiring includes single star wiring and double star wiring while triangle wiring includes single triangle wiring and double triangle wiring. The double triangle wiring is gradually eliminated due to complicated wiring and high cost. Low voltage shunt capacitors mostly use triangular wiring and high voltage shunt capacitors, especially for high voltage shunt capacitors with large capacity, mostly use star wiring.

Self-healing type low voltage shunt capacitor is suitable for the AC power system with working frequency 50Hz or 60Hz, rated voltage 1000V and below and is connected in parallel with load, in order to improve the power factor of system and reduce line loss, improving the voltage quality. It is widely used to improve the efficiency of power supply equipment, local compensation of the inductive equipment such as motor and transformer and electric furnace, electric traction engine, UPS systems and power system harmonic filtration and other aspects.