- #1
orla22
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If the line current is 240V, 400Hz, 3 phase generator supplies a balanced 3 phase star connected load through a long 3 core cable. load phase is a 0.25 ohms resistor in series with a 130 (nano)H inductor. 3 core cable has negligable resistance and a line resistance of 0.1 ohms.
How do hand calculate the real power.
I can work it out but can't get the right answer can someone help...
I know the formula is P=V.I.Cos(ange)
i know to find angle:
Z=R+jX
X=XL-XC
i get X to equal 3.267e-4 ohms.
therefore Z = 0.25 + j3.267e-4
so the angle is 0.0749
i know how to find current:
V=IZ
115/0.25+j3.267e-4
I=460
so real power = 115 x 460 x cos (0.0749) = 52900 W but the answer is 59113 W
How do hand calculate the real power.
I can work it out but can't get the right answer can someone help...
I know the formula is P=V.I.Cos(ange)
i know to find angle:
Z=R+jX
X=XL-XC
i get X to equal 3.267e-4 ohms.
therefore Z = 0.25 + j3.267e-4
so the angle is 0.0749
i know how to find current:
V=IZ
115/0.25+j3.267e-4
I=460
so real power = 115 x 460 x cos (0.0749) = 52900 W but the answer is 59113 W