# Practical Transformer

A practical Transformer is a type of transformer in which the input power is not equal to the output power. it means there are copper loss and iron loss appearing in the practical transformer.

Input power ≠ output power

## Equivalent Resistance

We know that an ideal transformer is a type of transformer in which the input power is equal to the output power which means no losses occur in the transformer. Still, the practical transformer is different to an ideal transformer because the input power is not equal to the output power in the practical transformer due to copper losses and iron losses.

primary and secondary windings have some value of resistance that causes the voltage drop in the practical transformer.

The primary winding resistance is R1 and the Secondary winding resistance is R₂.you can easily transfer one resistance to another.

If we need to transfer the secondary winding resistance R₂ toward the primary side simply divide it with K² and it represents R'₂.

R'₂=R₂/k² =equivalent Secondary Resistance

The copper losses of secondary are equal to  I²R.

I1²R' = I²R

R'= {I2:I1}²R

if we Neglect No load current Io

I:I1=1:k

R'=R₂/K²

Same we transfer Equivalent primary resistance toward secondary

R'=RK²: equivalent primary Resistance

## Equivalent Circuit of an Electrical Transformer

Let's Suppose The transformer Resistance and Leakage reactance are outside the windings and No load Current Io flows in the pure inductance Xo and Non-Inductive resistance Ro.

Xo = E1/Io

Ro = E1/Io

We know that

E2/E1 = N2/N1 = K

To make the calculations easy we simply transfer voltage, and current on one side.

E'₂ = E₂/k=E₁

The output voltage of the primary equivalent

V'₂ = V₂/K

Primary Equivalent of secondary current
I'₂=KI

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