Importance of power factor:
The lower the power factor of an installation, the higher will be the amount of current drawn from the source for the same kW rating.
The majority of AC electrical machines and equipments draw from the supply power (kVA) which exceeds the required useful power (kW).
This is due to reactive power (KVAR) necessary for alternating magnetic field.
The ratio of useful power (kW) to apparent power (kVA) is termed as the power factor of the load.
The reactive power is indispensable and constitutes an additional demand on the system.
The power factor indicates the portion of the current in the system performing useful work
A power factor of unity (100 percent) denotes 100 percent utilization of the total current for useful work where as a power factor of 0.70 shows that only 70 percent of the current is performing useful work.
