(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

the circuit values of a 60Hz,20kVA 2400/240V real transformer:

R1=3.0Ω

X1=j6.5Ω

R2=0.03Ω

X2=0.07Ω

Xm,magnetizing reactance=j15kΩ

Rc,core loss resistance=100kΩ

the transformer with rated load is said to be having a lagging power factor of 0.8

compute

1. primary and secondary current

2.primary and secondary voltage

3.source voltage

4.power loss in the transformer

5.power delivered to the load

6.input power

7.power effiency

2. Relevant equations

3. The attempt at a solution

1.I1=20k/2400=8.33A

I2=20k/240=83.33A

2.V1=2400V

V2=240V

3.Is=(2400/100k)+(2400/j15k)+8.33

=8.36 L -1.10°A

Vs=V1+Is(3+j6.5)

=2426.11 L 1.27° V

4. power loss=Pcore+Presistance

=[(2400^2)/100k]+[(8.33^2)3]+[(83.33^2)0.03]

=474.08W

5. Vout=V2-I2(R2+jX2)

=240-(83.33)(0.03+j0.07)

=237.5V

Pout=237.5(83.33)(0.8)

=15832.7W

6.input power=VsxIs

=2426.11x8.36

=20282.28W

7.effiency= 15832.7/(15832.7+474.08)x100%

=97.09%

this is my solution

i think all is wrong

please help me solve

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Real transformer question! help me solve it please!

Can you offer guidance or do you also need help?

Draft saved
Draft deleted

**Physics Forums | Science Articles, Homework Help, Discussion**