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Electric Drives Mach

QUESTIONNO. $4[25$ marks$]$

Short circuit and open$-$circuit tests were performed on a single $-$ phase transformer which is rated at $50$kVA,$6360\frac{V}{240}V.$ The results obtained from the tests are provided in Table $2$ below.

Table $2$: Open$-$Circuit and Short$-$Circuit Data

$\backslash$table$[[$Type of Test,$\backslash$table$[[$Primary$],[$Voltage$],[($Volts$)]],\backslash$table$[[$Primary$],[$Carrent $($A$)]],$Power $($W$),\backslash$table$[[$Secondary$],[$Current $($A$)]]],[$Open$-$Circuit,$6360,1\mathrm{.}0,2000,],[$Short$-$Circuit,$180,,2000,175]]$

You are required to calculate:

i$.$ The core$-$loss resistance.

ii$.$ The magnetizing reactance.

iii. The rated priunary curreat.

iv$.$ The rated secondary current.

v$.$ The percentage of rated load at which the short$-$circuit test was carried out.

vi$.$ The equivalent winding resistance.

vii. The total power loss at full load.

viii. The per unit efficiency of the transformer when supplying full load at a power factor of $0\mathrm{.}8$ lagging.