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Homework Statement
For the balanced threephase loads shown in FIGURE 3,
ZY = (15 + j15) Ω and ZΔ = (45 + j45) Ω. Determine:
Uploaded file C1.png
(a) the equivalent single Δconnected load,
(b) the equivalent single Yconnected load obtained from the ΔY transformation of (a) above,
(c) the equivalent single Yconnected load obtained by transforming the Δ subload of FIGURE 3 to a Y and with the starpoints of the two Ysubcircuits connected together,
(d) the total power consumed in case (a) above if the line voltage of the threephase supply is 415 V at 50 Hz.
Homework Equations
The Attempt at a Solution
For (a) P=Q=R=(15+15i)
Star "PQR" >Delta "ABC" equivelant =
A=PQ+QR+RP/R
Since the loads QPR are all the same value and same equation form then A=B=C, ((15+15i)*(15+15i)+(15+15i)*(15+15i)+(15+15i)*(15+15i))/(15+15i)=45+i45
Delta equivelant is A=45+i45, B=45+i45, C=45+i45
For(b) The reverse of (a) I assume; Delta > Star =
Q=AC/A+B+C
P=AB/A+B+C
R=BC/A+B+C
Q=P=R= 15+i15
Questions seems deceptively easy for my liking
(c) Is the diagram C2.png how the transformation and two Y subcircuit connected star points should look like?
I need a hint on how to form the equations for this if it is correct(im sure its obvious but im not sure.)
Any help greatly appreciated.
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