1.1 Write a computer program to calculate the three-phase fault current for a fault at F in Figure 1.16, with the network normal, and with one line at a time removed from service.

The positive-sequence impedance data are given in the accompanying table.

Use the commonly made assumption that all prefault resistance values are (1.0 + j0.0) pu, and neglect all resistance values.

Calculate the contribution to the fault flowing through the CB B1, and the voltage at that bus.

For each calculated case, consider the two possibilities: CB B2 closed or open. The latter is known as the stub-end fault.

6 Figure 1.16 Problem 1.1 System data for Figure 1.16 Positive sequence impedance From To 0.0+j0.1 0.05 + j0.15 0.04 + j0.2 0.01 + j0.1 0.015 + j0.15 0.01 + j0.19 0.01 + j0.19 0.03 + j0.1 0.0 +j0.08 6 Figure 1.16 Problem 1.1 System data for Figure 1.16 Positive sequence impedance From To 0.0+j0.1 0.05 + j0.15 0.04 + j0.2 0.01 + j0.1 0.015 + j0.15 0.01 + j0.19 0.01 + j0.19 0.03 + j0.1 0.0 +j0.08