Question

A 2000 V/200 V, 20 kVA, two winding single-phase transformer is reconnected as a step up auto-transformer having 200 V/2200 V ratings. Then the power rating for the auto transformer will be

Answer 1

2000 V/200 V, 20 kVA, two winding T/F
Reconnected as Auto T/F$\to 200/2200V$


For current distribution...
$V_1{I}_1=V_2{I}_2$
$\Rightarrow 200\times I_1=110A$

$\therefore$ Auto transformer rating should be
$V_1{I}_{1}or{V}_2{I}_2$

$\Rightarrow 200\times 110\left(or\right)2200\times 10$
$=22000\left(or\right)22kVA$