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QUESTION 5 (CO1,PO2,C5) A 3 phase synchronous generator is connected to an infinite busbar via a transformer and double circuit line (Fig. Q 5). The gener&or transient reactance is 0.25 p.u. on its rating of 500 MVA, the transformer reactance is 0.18 p.u. on its rating of 750 MVA and each 275 kV overhead circuit has a reactance of 50 2. The infinite busbar has a voltage of 1 p.u. and it may be assumed that the internal transient voltage of the generator is 1.25 p.u. A 3-ph fault occurs on one of the circuits close to the transformer busbar when the generator is producing 450 MW. The fault is cleared by isolation of the faulted circuit. Using a base of 500 MVA, Sketch the power angle curves after calculating the pre-fault, fault, post-fault conditions and mark the equal area criterion. [ 15 Marks] FX- Fig. Q 5 infinite bus bar