AC MACHINES-1 (66761) Theory
4. Understand equivalent circuit of transformer, magnetic leakage and leakage reactance of transformer.
4.1. Draw the equivalent circuit and vector diagram of a transformer.
What is the equivalent circuit of a transformer?
Equivalent Circuit diagram of single phase Transformer
Equivalent circuit diagram of a transformer is basically a diagram which can be resolved into an equivalent circuit in which the resistance and leakage reactance of the transformer are imagined to be external to the winding.
The equivalent circuit diagram of transformer is given below:-
Where,
R1 = Primary Winding Resistance.
R2= Secondary winding Resistance.
I0= No-load current.
Iµ = Magnetizing Component,
Iw = Working Component,
This Iµ & Iw are connected in parallel across the primary circuit. The value of E1 ( Primary e.m.f ) is obtained by subtracting vectorially I1 Z1 from V1 . The value of X0 = E1 / I0 and R0 = E1 /Iw. We know that the relation of E1 and E2 is E2 /E1 = N2 /N1 = K , ( transformation Ratio )
From the equivalent circuit , we can easily calculate the total impedance of to transfer voltage, current, and impedance either to the primary or the secondary.
