Power Factor Improvement

To understand power factor improvement, it's required that we have to understand about power triangle. This concept is very important to support our sharing today. let's look at figure below.

From the figure above, we can know that power factor or cos pi is comparison of active power (P) to apperent power (S). To improve cos pi of electric power system is required reactive power (Q) supplied to the electrical system. How much is Q required? It depends on the cos pi to be achieved. So, how to determine Q ? look at figure below.

Q or Q (C) can be calculated by knowing active power (P) and initial cos pi and final cos pi to be achieved.
Let's learn an example below.

Suppose we wish to increase power factor from 0,8 to 0,9 in a tree phase system (V= 400 Volt) absorbing an active power of 100 kW.

• The absorbed current shall be :
• I   = P/(1,732*V*Cos pi) = 100*1000/(1,732*400*0,8) = 180 A
• Q = P*(tan pi0-tan pi1) kVar = 100*(0,75-0,48) = 26 kVar

Due to power factor improvement, the absorbed current decreases from 180 A to 160 A.

•  I   = P/(1,732*V*Cos pi) = 100*1000/(1,732*400*0,9) = 160 A

From the example above, there are several adventages by improving power factor :

•  Reduction of losses
•  Reduction of voltage drops
•  Increase the performance of electrical equipment and line

Please comment after reading my posting.
Thank you

Regards,
HI