We know that power factor is defined as the ratio of KW to KVA and low power factor results when KW is small in comparison to KVA. This would occur when KVAR power is large. Major causes for large KVAR is inductive loads present in our electrical system, some of the equipment which are having large KVAR is as below:
a) Transformers
b) Inductive Motors
c) Inductive Generators
d) High intensity discharge lighting
Reactive power (KVAR) required by inductive loads increases the amount of apparent power (KVA) in distribution system. This increase in reactive and apparent power results in a large angle θ (measured between KW and KVA. As θ increases, cosine θ (or power factor) decreases, so inductive loads (with large KVAR) result in low power factor.
NEED OF IMPROVING POWER FACTOR:
a) To avoid the penalty imposed by distribution utilities for poor power factors.
b) Now utilities have been started the billing in KVAH instead of KWH, so improved power factor helps in reducing our electricity charges.
c) Reducing demand
d) Increased voltage level in electrical system due to which efficiency level of motor gets better as well as life span also gets increased.
IMPROVING POWER FACTOR:
We have seen from above that power factor got decreased due to inductive loads, to improve the power factor equipment like capacitors & synchronous generators could be installed.
a) Installing Capacitors: Installing capacitors decreases the magnitude of reactive power (KVAR) and increases power factor. Reactive power (KVARS), caused by inductive loads always acts at a 90 Degree angle to working power (KW)
Inductance and capacitance react 180 Degrees to each other. Capacitor store KVAR and release energy oppose the reactive energy caused by the inductor present in electrical system, the presence of both i.e. capacitor and inductor in the same circuit results in the continuous alternating transfer of energy between the two. Thus, when the circuit is balance, all the energy released by the inductor is absorbed by the capacitor. In this way power factor can be improved in an electrical system.
b) Minimizing Operation of Idling or Lightly Loaded Motors: As we know low power factor is caused by the presence of induction motors, but more specifically, low power factor is also caused by running induction motors which are lightly loaded, so avoid these type of operation.
c) Avoiding Operation of Equipment above its Rated Voltage
d) Replacing Standard Motors as they Burnt Out with Energy Efficient Motors.
So with the help of above we can improve the power factor of our electrical system and able to reduce power loss, and our electricity charges due to poor power factor.
In case any enquiry feel free to contact us at info@saielectricals.com