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Single phase transformer

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Member level 5
Dec 11, 2010
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i were facing a problem on single phase transformer on calculation part.
i been sketches out the single phase transformer equivalent circuit.
and some information given
f = 60hz
s = 20kVA
V1 = 2400v
V2 = 240v
R1 = 3Ω
R2 = 0.03Ω
X1 = 6.5Ω
X2 = 0.07Ω
Xm = 15kΩ
Rc = 100kΩ
lagging P.F. = 0.8

and here the problem come. i were trying to solve the problem.
which is
i got Xeq1 = R1 + a^2R2 = 13.5Ω, and Req1 = X1 +a^2X2 = 6Ω
i got primary voltage is V1 = 2400V and V2' = aV2 = 2400V
how do i calculate the primary current and secondary current?
and also the source voltage.

thank you and much appreciate with your help to solve the problem

...i got Xeq1 = R1 + a^2R2 = 13.5Ω, and Req1 = X1 +a^2X2 = 6Ω...

should be as?

Req1 = R1 + a^2R2 = 13.5Ω, and Xeq1 = X1 +a^2X2 = 6Ω

is it ?

sorry, is a typo error. shud be the same as u say

shall i need to include Xm and Rc into the formula to calculate the Ip or Is?
the source voltage got any formula?

I would assume Source Voltage as 2400V (equal to V1, in specifications mentioned by you)
Yes, you need to include Xm & Rc into current calculations Ip. Ip=Io + Secondary (or load ) current reflected in primary; here Ip is current drawn from source

how could i get voltage load, it do not gave any resistance load in circuits

how could i get voltage load, it do not gave any resistance load in circuits
You didn't tell the exact exercise text, but you're asking for a secondary current, so there should be a load, isn't it? The only hint for the load I found is the P.F. number, but I think you'll need more information about the load, I think.

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