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.

Oddbjørn Gjerde

WP2 Lead
+47 99 730 027
Oddbjørn Gjerde
WP2 Lead


Reference in CINELDI