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Find the fault current (in amps) for a three phase, B-C Phase, and A phase to ground bolted fault under system normal conditions at the location shown. Assume a pre-fault voltage of 1.0 pu, and negligible fault resistance. Note that the fault is in the middle of the line. therefore line impedance from the fault to either transformer is % of the total impedance of the line. Show all work, including sequence networks. Hint: using a MVA base of 20MVA will save a few conversions. X Δ line 1 G2 G1 Fault at 50% of the line G1 Gerw = 14.4kV Gerva 145 MVA X"=-0.15pu X-0.2 pu X-455pu 11 150 MVA X18% X-18% 14.4-63kV line 1 X-X; -7.938 ohms X 23.814 ohmns T2 20 MVA X -10% X -10% 63kV-7.2kV G2 Gene = 7.2k Gen20 MVA X"d=0, 1pu X-0.12pu X-455pu

Draw the sequence network and determine the fault current (in amps) for a Single Line to Ground fault at the location shown. Assume a pre-fault voltage of 1.03 pu, and negligible fault resistance ye System SAM Nominal ky 230V MVA 100 MVA X-0.1 pu X-0.1 pu X-0.2 pu II 100 MVA X-10% X-10% 230-13.8V