Power Factor

What is power Factor?

• Ratio between real and apparent power is known as power factor.

PF = KW/ KVA

OR

• Cosine of phase angle between Real and apparent powers is known as power factor.

PF = cos θ

Disadvantages of Low power Factor:

• Large KVA rating of equipment:

KVA= KW / cosθ

If equipment has low power factor  then KVA rating of the equipment greater making the equipment larger and expensive

• Greater conductor size.
• Larger copper losses, grater the KVA rating, greater the current, due to large current copper losses also increases
• Poor voltage regulation.
• High energy bill:

Low power factor  increases the KVA demand which in turn increases the energy bill.

Energy bill = KVA demand charges + energy charges