Single line to ground-fault locations method developed and tested in simulation
Challenge and objective
Unlike short circuit faults, there has not been a well-established method for detecting and locating single line to ground (earth) faults in isolated systems.
A method for earth fault locationin unground distribution networks is needed. The method should be cost effective, simple to implement and its accuracy should not be affected by variation in measurement inaccuracy, load situation, fault resistance etc.
Work performed
Two novel current based methods for locating earth faults in isolated closed ring operating MV networks were developed.
The methods are based on utilising zero and negative sequence current during fault on ring connected feeders.
The performance of the methods was investigated by conducting multiple simulation tests considering variation in measurement inaccuracies, load, fault resistance, and other parameters.
Significant results
During the simulation tests, both methods showed good accuracy. The maximum distance error was in the range of a few hundred meters.
The impact of measurement inaccuracy, load asymmetry and fault resistance were minimal.
Impact for distribution system innovation
The simulation results were promising and strengthens the prospect of further testing of the methods in real networks and adoption of the methods for a real-world implementation.
