# Impedance of a Transformer circuit

#### mazzi

Joined Dec 29, 2011
3
Hello all,
Given a transformer equivalent circuit shown on the attached document of
R1 = 2.1Ω, R2 = 5.2Ω, X1= 4.1Ω, X2= 3.25Ω, N1 = 800, N2 = 1250, R0 = 122Ω,
X0 = 107Ω, RL = 20.5Ω, V2 = 22V.

I need to calculate the impedance of the circuit.
How do I calculate the impedance Z of the circuit taking account of the magnetizing branch.

Thanks

#### jegues

Joined Sep 13, 2010
733
Hello all,
Given a transformer equivalent circuit shown on the attached document of
R1 = 2.1Ω, R2 = 5.2Ω, X1= 4.1Ω, X2= 3.25Ω, N1 = 800, N2 = 1250, R0 = 122Ω,
X0 = 107Ω, RL = 20.5Ω, V2 = 22V.

I need to calculate the impedance of the circuit.
How do I calculate the impedance Z of the circuit taking account of the magnetizing branch.

Thanks
First you need to tell me whether or not the values you've given for each parameter given is referenced at the LV side or HV side.

If they aren't they must first be reflected.

The equivalent impedance should be as simple as a series/parallel combination of impedances provided the appropriate parameters are found.

#### mazzi

Joined Dec 29, 2011
3
The voltage is applied to the primary winding and the parameters are the values of the exact equivalent circuit.

thanks

#### jegues

Joined Sep 13, 2010
733
The voltage is applied to the primary winding and the parameters are the values of the exact equivalent circuit.

thanks
Okay so to reduce everything down to one impedance simply preformed series/parallel impedance combinations.

Are you still confused?

What are you having difficulties with?

#### MossyIRL

Joined Dec 29, 2011
3
Your diagram is a little confusing as V1 would normally indicate Vprimary.
But you also have Rload which is on the secondary??

Also if this was say, the primary side, should R2 and X2 not be represented by R2' and X2'..?