Engineering Shady data from a transformer’s short-circuit test

[Kamakiri]

Homework Statement

Data from the short-circuit test of a 60-Hz, 100-kVA, 4600–230-V transformer are:

V_SC = 172.3 V
I_SC = 20.2 A
P_SC = 1046 W

Get the per-unit parameters.

2. Relevant equations

I_SC ≠ I_rated, so how will I solve the problem?

The problem is from the book with ISBN 0130612103.

 

[Hesch]

I_(SC) is unequal to the rated current, so how will I solve the problem?

Rated current is about 100 kVA / 4.6 kV = 21.7 A, so the error-ratio is 21.7 A / 20.2 A = 1.076

So you multiply V_sc and I_sc by 1.076.

Multiply P_sc by 1.076². ( P = R * I². )

 

[Kamakiri]

The per-unit parameters are the same whether or not I multiplied the data by 1.076 or 1.076².