1. The problem statement, all variables and given/known data For the balanced three-phase loads shown in FIGURE 3, ZY = (15 + j15) Ω and ZΔ = (45 + j45) Ω. Determine: Uploaded file C1.png (a) the equivalent single Δ-connected load, (b) the equivalent single Y-connected load obtained from the Δ-Y transformation of (a) above, (c) the equivalent single Y-connected load obtained by transforming the Δ sub-load of FIGURE 3 to a Y and with the star-points of the two Y-sub-circuits connected together, (d) the total power consumed in case (a) above if the line voltage of the three-phase supply is 415 V at 50 Hz. 2. Relevant equations 3. 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 sub-circuit 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.