Transformer Impedance and kVAr Compensation

For calculating Transformer Impedence compenseting KVAR of 2000KVA Transformer

Transformer rating is 2000 KVA

Impedence of the transformer is : 6.25% (As per the vendor)

Let X be the total load in KW

So total load in KVA = KW/ P.F

Intial P.F is 0.8

Improved P.F should be = 0.99

Can any one let me know what is the base formula for calculating Transformer Impedence compenseting in KVAR

Transformer Impedence

compenseting in KVAR = =Square of loading of trans X %Z X Rating of Trans

Could any one the basic of the formula where it is derived from.

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