# A factory draws 100 kW at 0.8 p.f. lagging from a 3-phase, 11 kV supply. It is desired to raise the p.f. to unity using the capacitor bank. The total power rating of the capacitor bank is

A factory draws 100 kW at 0.8 p.f. lagging from a 3-phase, 11 kV supply. It is desired to raise the p.f. to unity using the capacitor bank. The total power rating of the capacitor bank is

### Right Answer is: 75 kVAR

#### SOLUTION

Reactive Power of capacitor bank required for power factor correction is given by

$Q = P\left( {\tan {\phi _1} – \tan {\phi _2}} \right)$

Where, φ1 = power factor angle before compensation

φ2 = power factor angle after compensation

P = Real Power

Given that cos φ1 = 0.8

⇒ φ1 = 36.86 degrees

Cos φ2 = 1

⇒ φ2 = 0 degrees

Now,

Q = P(tan(36.86) − tan(0)) = 74.87 kVAR

Scroll to Top