Question

The single-line diagram of a three-phase power system is shown. Equipment ratings are given as follows: 

The inductor connected to generator 3 neutral has a reactance of \(0.05\) pu using generator 3 ratings as a base.

1. Draw the zero-, positive-, and negative -sequence  reactance diagrams using a \(1000 \mathrm{MVA}, 765 \mathrm{kV}\) base in the zone of line \(1-2\).

2. Faults at bus 2 are of interest. Determine the Thevenin equivalent of each sequence network as viewed from the fault bus. Prefault voltage is \(1.0\) pu. Prefault load currents are neglected.

3. Determine the subtransient fault current in pu and kA during a bolted three-phase fault at the fault bus \(2 .\)

4. Determine the subtransient fault current in pu and kA during a bolted single line-to-ground fault at the fault bus \(2 .\)

5. Determine the subtransient fault current in pu and kA during a bolted line-to-line fault at the fault bus \(2 .\)

6. Determine the subtransient fault current in pu and kA during a bolted double line-to- ground fault at the fault bus \(2 .\)

7. Verify the results of calculations by performing computer simulation using ETAP software.

8. Present a written repot with the results of all calculations and simulation. Make conclusions.

Answer 1

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