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In the system shown in Figure 1, the transformer is connected star-star with both star points grounded and the generator is connected in star with its star point grounded. The per unit sequence reactances of each element on a {SBASE} MVA base are given in Table 1 and the voltage levels are given in Table 2.

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{image('resources/question-resources/FA3Bus.png')}

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Figure 1: A section of the distribution system

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G1

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T1

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L

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X1

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{G12}

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{T120}

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{L12}

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X2

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{G12}

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{T120}

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{L12}

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X0

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{G0}

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{T120}

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{L0}

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 Table 1: Sequence reactances (p.u. on {SBASE} MVA base)

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G1

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T1

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L

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BASE

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{VG}

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{VG}/{VL}

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{VL}

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Table 1: Voltage bases (kV)

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If a line-line fault occurs at bus 3 with zero fault impedance, calculate the magnitude of the fault current flowing between phases at the fault point (in p.u.).

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$ I $ =  [[0]]  p.u.

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What is the fault current at the fault point in kA?

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$ I $ =  [[0]] kA

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What is the fault current flowing from the generator in kA?

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$ I $ =  [[0]] kA

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