A three-phase generator is connected to a strong grid with line-to-line voltage 14 kV and frequency 50 Hz. The generator is rated at 15 kV and 180 kVA. The resistance in the windings is 2 Ohm/phase and the reactance is j3 Ohm/phase. The current in one phase was measured to be: I= 1500 / -25º A.

What is the line-to-neutral voltage of the generator, |Ei|=____ kV.

Hi, I've got issues understanding what I should calculate and what "Ei" actually means?

I tried to calculate the I(phase)*Z(polar) to get the Ei(line-to-neutral), which gave me 5408,32V. Which is wrong. Then I tried to take the V(line-to-line)/sqrt(3) to get Ei, which gave me 8082V which is also wrong. How am I supposed to do it?

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    \$\begingroup\$ Show how you calculated those values and also explain what the correct answer is. \$\endgroup\$ – Andy aka Feb 9 at 12:35
  • \$\begingroup\$ @Andyaka, I did explain how I calculated? I took the phase current multiplied with the impedance's polar form, which should give me the phase voltage. This was, however, incorrect. Then I attempted to take the line to line voltage divided with sqrt(3) to get the line to neutral voltage, which was also wrong. I can't give you the correct answer because I don't know what it is. \$\endgroup\$ – gripen Feb 9 at 13:17
  • \$\begingroup\$ I’m voting to close this question because it's homework without an attempt at a solution \$\endgroup\$ – Voltage Spike Feb 9 at 14:32
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    \$\begingroup\$ @VoltageSpike I've attempted to solve it twice, with two different approaches?! I have written every step of both processes. \$\endgroup\$ – gripen Feb 9 at 14:52
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    \$\begingroup\$ @gripen saying "I've tried this" isn't the same as showing your work. What if you applied it wrong or missed a step? Am I reading your current correctly to be 1500A at 25 degrees lag? That seems impossibly high if the generator is putting out ~14kV and is only rated at 180kVA. \$\endgroup\$ – K H Feb 10 at 7:24

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