power factor correction using capacitor bank

inductive loads requires two kind of powers

1) Active Power: power to perform work
2) reactive Power : power to create and maintain electro-magnetic field.

the ratio of active power(kw) to apparent power(kva) is called power factor.

major loads in industries ,factories are inductive loads like A.C. motors ,transformers ,induction furnaces etc., so power supplied by electrical board is utilised for both doing some work and creating electromagnetic field.

Hence actual load on distribution system is vector sum of active power and reactive power. i.e., apparent power.

kva=(kw² + kvar²)^1/2
therefore for industries and for commercial purpose electricity bills are based on  kvah , unlike for domestic purpose bills are based on kwh .
so if reactive power consumption  is high apparent power consumption is high and bill will be high .
we need to adopt some methods to reduce reactive power consumption so capacitors are installed near loads which will generate some reactive power which will compensate reactive power developed by inductive loads.
consider following example

if we are not using capacitor bank for same kw PF is reduced and kva increased but if we are using capacitor bank 410 kvar for same power PF improved and kva reduced.

capacitors used for PF correction

inside of capacitor bank panel board in a factory.