During No load why the power factor of the transformer is very low ?

During No load why the power factor of the transformer is very low ?
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1 Answer

Answer :

A. Current flowing through the transformer consists of two components. Magnetizing current (Im) which is in quadrature (900) to the applied voltage and in phase current which is in phase to the applied voltage. During no load condition most of the excitation current drawn by the transformer from the primary winding is to magnetize the path. Hence excitation current drawn by the transformer during no load condition mostly consists of magnetizing component of current which is used to provide magnetic field in transformer circuits (Inductive nature). Therefore as the nature of the load is inductive, hence the power factor of transformer during no load condition will by in the order of 0.1 to 0.2
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