A single-phase 300-kVA, 220/4400 V, 60 Hz transformer yielded the following information when tested: High voltage...

A single-phase 300-kVA, 220/4400 V, 60 Hz transformer yielded the following information when tested: High voltage winding open: Voltage=220 V, Current=40 A Power=l 000W Low voltage terminal shorted: Voltage= 195 V, Current=68.18A Power=4000W Find the equivalent circuit of the transformer as viewed from the high voltage Calculate the .efficiency of the transformer when it delivers its rated load at rated terminal voltage and 8 power factor lagging.

Solutions

Expert Solution

Open circuit test gives (i) the core loss at rated voltage and frequency (ii) the shunt branch parameters of the equivalent circuit and (iii) turns ratio of the transformer.

Short circuit test gives (i) ohmic loss at rated current and frequency and (ii) the equivalent resistance and equivalent leakage reactance.

Manojponduru answered 2 hours ago

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