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Ohmic value and per unit calculations?
For the circuit attached, calculate the required sending end voltage (Vs), when a load of 1MVA, 0.8 power factor is supplied at 400V. Use both the ohmic value and per unit methods.
1 Answer
- 1 decade agoFavorite Answer
Are you asking somebody to do the problem for you, or just have one question about something? Why don't you try it and upload your work, then we can check it...or maybe come back with a more specific question.... To get you started:
The load can be transfered into an impedence, since you have the Voltage at the load bus, and the S value (VA plus a power factor):
The equation is:
Z = mag(V)^2 / conj(S)
And remember, your S needs to include the power factor information. i.e.: angle(S) = inverse_cos(PowerFactor) ....and the angle is determined by leading or lagging information. In the case you listed, there is no information as to if it is a leading or lagging load, so we can assume lagging - as it is almost ALWAYS lagging. So, the angle on S will be positive. finishing up, S = 1MVA @ 36.87 degrees.
This should get you started, I hope!
