TRANSFORMER THEORY
Transformers
Summary
The important information covered in this chapter is summarized below.
Transformer Theory Summary
The induction of an EMF in a coil by magnetic flux lines generated in
another coil is called mutual induction.
The turns ratio is defined as the ratio of turns of wire in the primary
winding to the number of turns of wire in the secondary winding.
The ratio between the primary and secondary impedances is referred to as
the impedance ratio.
Efficiency of a transformer is the ratio of the power output to the power
input.
In a delta connection, all three phases are connected in series to form a
closed loop.
In a wye connection, three common ends of each phase are connected
together at a common terminal, and the other three ends are connected to a
three-phase line.
In a D connected transformer:
VL
Vf
IL
3 If
In a Y connected transformer:
IL
3 Vf
IL
If
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