ABSTRACT
The fault calculation process is the same for any other voltage and system arrangements, which would vary only the system constants and sequence network configurations. Faults at other locations in the system involve a repeat of the calculations. To satisfy Kirchhoff's law, all the currents throughout the system add or subtract correctly. Thus the currents up the several grounded transformer neutrals must equal the fault current to ground. In a radial-type system, typical of many distribution and industrial systems, the power source and grounded transformer are at the same end without a power or zero-sequence source at the other end. The per unit voltages can be determined from the sequence networks from the fundamental equations through, and the phase voltages from the fundamental equations through. In a power system with balanced voltages but unbalanced impedances, it is possible for the neutral to fall outside the voltage triangle.
