A new method of grounding performance evaluation of multigrounded power systems by ground current measurement

Measurement of ground resistance is one of the most popular method of evaluating grounding electrode performance. Even though the deterioration of grounding performance caused by corrosion or accidental loss of electrodes can be partially detected by regular measurement of ground resistance, it is difficult to conduct the periodic measurement in case of an energized power substation with multigrounded overhead ground wires and/or distribution line neutrals interconnected with substation grounding grid. In this paper, an alternative method for grounding performance evaluation of multigrounded systems without removal of interconnections between grounding systems has been proposed. A field test result has shown the validity of the proposed test method.