# Equivalent circuit of transformer

Equivalent circuit of transformer

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Equivalent circuit of transformer:

Let V1 is the AC supply given to primary winding of transformer.

Ris the resistance of primary winding.

X1 is the leakage reactance of primary winding.

I1 is primary current.

Ic is core loss current.

Rc is core loss resistance. Core loss is also called as iron loss, which is hysteresis loss and Eddy current loss.

Im is the magnetizing current.

Xm is the magnetizing reactance.

I1' is the current through primary winding.

E1 is the primary induced EMF.

N1 is the number of turns at primary winding.

N2 is the number of turns at secondary winding.

E2 is the secondary induced EMF.

R2 is the resistance of secondary winding.

X2 is the leakage reactance of secondary winding.

I2 is the secondary current.

V2 is the output voltage.

Equivalent Circuit Diagram of Transformer Referred to Primary:

V1 -Primary Input voltage

I1 - Input Current

I0- Exciting current/ No load current

Im- Magnetizing component of no load current

Iw-Working component of no load current

R0- Core loss resistance

X0- magnetizing reactance

R1 -Primary winding resistance

X1 - Primary winding reactance

E1 –Induced emf in Primary winding

R2′ - Secondary winding resistance referred to primary

X2′- Secondary winding reactance referred to primary

I2-Secondary winding current

I2′– Primary equivalent of secondary current

K- Transformation ratio

V2- Secondary terminal voltage

V2′- Primary equivalent of secondary terminal voltage

ZL ′- Primary equivalent of load impedance

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