What is Power Factor Correction?

To get the concept of power factor correction, we must know the basic concept of electrical power factor. The electric power is developed in plants, and after that it is distributed among the consumer loads. That is the electrical energy is converted into other forms of energy. In general, power factor is a measure which tells that how efficiently the electric power is utilized to produced other kinds of energy (such as mechanical energy in motor). In fact, it is the ratio of Real or working power to apparent power. Ideally the power factor should be unity. But the consumer loads are mostly inductive in nature, which affects the overall power factor, and also affects the economy of power generation companies. So the power generation companies compensate this inductive power, by means of adding some capacitor element into the network.
They intentionally put some series of capacitor (arrangement is called as capacitor bank) into the circuit. Being capacitive load the capacitor leads the circuit current and compensate the inductive current, drawn by the consumers. In this way, a balanced condition is arises where the power factor becomes more or less unity. Capacitors are actually acts like reactive power generator. Power factor correction units are also necessary for small power applications. Low voltage power factor correction units shapes the input current, which will maximize the real power available from the source. These units are also makes a combination with regulatory elements and used in many low voltage applications such as SMPS. LV power factor correction circuits also use the capacitors. It ensures that the load circuit becomes the linear combination of resistive, inductive and capacitive element, which will maximizes the overall efficiency of the system.