Hello,(adsbygoogle = window.adsbygoogle || []).push({});

I just got a small question.

If a 50Hz grid line is carried underground for a distance of 10km. And it is also known that the capacitance is 400nF per phase per km. What is the total reactive power generated in the 10km length?

Then I could say that we have a total of 400nF * 10 = 4000nF per phase.

[tex] Power = \frac{V^2}{X_c} = \frac{400k^2}{\frac{1}{2 * \pi * 50 * 4000nF}} = 127MVAr. [/tex]

1. However, this is the power per phase isn't it? From my lecture notes it is the total reactive power however I can't figure out why.

2. Also, I'm trying to find the charging current in each phase of the line.

According to my lecturer power in each phase is the power I got earlier divided by 3, but the same capacitance is used if the formula I^2Xc is used.

Please help, this is really confusing me!

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# Homework Help: Underground cables

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