Normally the term Power Factor correction implies the following :

1. Measure the current power factor ( which will be influenced by the loads currently on line )

2. Decide the amount of correction to be done.

3. Based on pre-calibrated data, switch IN or OUT the required amount of capacitance into the power grid entering your premises.

4. Go back to Step 1.

Or that is what some companies claim they do.

Maybe some of our members have attempted it.

Raghu