Answer Happy

Give all your answers correct to 4 d.p. Part of a power system is illustrated in the figure below. Three synchronous generators are connected in parallel to the same 6.6 kV bus bars (G12 MVA, 0.08 pu; G2:5 MVA, 0.12 pu, 63.7 MVA, 0.16 pu) The feeder has reactance of 0.125 km and is 16 km long. The remote end of the feeder is connected to the primary of a 250 KVA, 6600/415 VN transformer, with reactance of 0.05 pu Select the common power base as 100 MVA G1 Feeder G2 Yyo G3 '9 Part a) Determine the generator X per unit reactance for the given common power base [3 marks] pu Xt' = Number X2= Number pu X;' = Numer pu Calculate the per unit and absolute values of the fault level and fault current if a three-phase short circuit takes place on the 66 KV bus-bars (point 1 in the figure above) [4 marks) locomo pu Sic = PU KA Soc MVA
Part b) Calculate the feeder and transformer per unit reactance (using the base voltage and base power of 6.6 kV and 100 MVA) [3 marks] Xc = Number p.u. (feeder) Xu Number p.u. (transformer) Calculate the per-unit and absolute values of the fault level and fault current if a three-phase short circuit takes place on the secondary of the transformer (point 2 in the figure above) [4 marks] Isc = Number pu Ssc = Number pu KA Isc = Number Ssc = Number MVA Part c) Using the text box below, discuss the method of analysis that has to be used in the case of asymmetrical faults which are the most important asymmetrical faults (150 words max)? [6 marks) (This question is manually graded) @a ESSE A. ATBIUS X, X Ω ΣΕ Editor Styles Font Size