In recent years, the power quality of the AC system has become a major concern due to the rapid increase in the number of electronic equipment, power electronics and high voltage system. Most of the commercial and industrial installation in the country has large electrical charges that are alone inductive in nature causing a lagging power factor that gives heavy penalties to the consumer by the power board. This situation is taken care of by PFC. The power factor correction is the ability to absorb the reactive power produced by a load. In the case of fixed loads, this can be done manually by switching capacitors, however in case of rapidly varied and dispersed loads, it is difficult to maintain a high power factor by manually switching on / off the capacitors in proportion to the Load variation within a facility. This inconvenience is overcome by the use of an APFC panel. 

In this document the measurement of the power factor of the load is made by the use of PIC microcontrollers and activate the capacitors necessary to compensate the reactive power and bring the power factor to the unit.

Power factor is the ratio of KW and KVA. KW is the actual load power and KVA is the apparent load power. It is a measure of the effectiveness with which the current becomes a useful work output. Most industrial electrical loads have a low power factor that does not exceed 0.8 and therefore imparts distribution losses. A poor power factor may be the result of a significant phase angle, usually the result of an inductive load such as an induction motor, power transformer or induction furnace. The existing reactive power is not included in the electric bill, however, this probably causes a loss of dissipation power in the load resulting in an increase in the electric bill bill. The penalty charge is just one of the problems however there are more other problems occurs if the power factor is low. They are

A) Additional losses in power cables

B) Significant voltage drop

C) Reduction of effective cable capacity

D) Transformer secondary voltage drop

E) Transformer losses