METHOD OF DETECTING GROUND FAULTS IN A NETWORK FOR DISTRIBUTION OF ELECTRIC POWER AND A DEVICE FOR CARRYING OUT THE METHOD

摘要

ABSTRACTA method and a device for detecting ground faults in a networkfor distribution of electric power from a power station from which anumber of lines, included in the network, emanate and where theground fault current IJ of each line is measured. According tothis method, that line is selected (10) which shows the greatestactive ground fault current IJR (8), alternatively the greatestground fault current IJ, or the greatest change in the groundfault current .DELTA.IJ. Thereafter, the measured ground fault current,or the change thereof, in the selected line is compared (12) withat least one predetermined reference value (11). A fault indica-tion is obtained (13) at a level exceeding the reference value.(Figure 1.)