Why Is The Efficiency Of A Three-phase Induction Motor Is Less Than That Of A Three-phase transformer ?

Why Is The Efficiency Of A Three-phase Induction Motor Is Less Than That Of A Three-phase transformer ?
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1 Answer

Answer :

Three phase Induction motor is nothing but a rotating transformer .

Due to rotating nature, there are friction and windage losses associated with it.
On the other hand, the three-phase transformer is a static device, thus there are no rotational losses.
Thus the efficiency of three-phase induction motor is less than that of a three-phase transformer .
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