Chapter: Electrical Engineering and Instrumentation : Transformer
Transformer on No-Load
Transformer on No-Load
When the
primary of a transformer is connected to the source of an ac supply and the
secondary is open circuited as shown below, the transformer is said to be on no
load. The Transformer on no load alternating applied voltage will cause flow of
an alternating current I0 in the primary winding, which will create
alternating flux Ф. No-load current I0, also known as excitation or
exciting current, has two components the magnetizing component Im and the
energy component Ie as shown in phasor diagram .Im is
used to create the flux in the core and Ie is used to overcome the hysteresis
and e ddy current losses occurring in the core in addition to small amount of
copper losses occurring in the primary only (no copper loss occurs in the
secondary, because it carries no current, being open circuited.)
Related Topics