Measurements and Computations of Fault Current Distribution on Overhead Transmission Lines

Improved analytical methods for assessing the effects of a ground fault on a transmission line are discussed. Both simplified and more complex calculation techniques are shown and compared with staged fault tests. The simplified approach provides approximate results for the calculation of the fault current in the structure as a fraction of the total single phase to ground fault current. The complex calculation provides results for single, double, and three phase to ground faults at any structure with variable structure resistance along the transmission line. The simple formula lends to calculator use whereas the complex calculation is geared for a computer.