Testing Ground Fault Protection of Generating Units With Frequency-Selective Grounding

S. A. Saleh, Razzaqul Ahshan, M. E. Valdes, D. Jewett, C. Mardegan, J. Meng, S. A.R. Panetta

Research output: Contribution to journalArticlepeer-review


This paper experimentally evaluates responses of ground fault protection for synchronous generators, which are grounded using frequency-selective grounding. Frequency-selective grounding is designed to provide a low ground impedance path (similar to solid grounding) for high frequency zero-sequence current components. This grounding system also provides an impedance similar to a low-resistance grounding for low frequency zero-sequence current components. The frequency-dependent equivalent impedance of frequency-selective grounding can affect ground potential and current, which are typically used as inputs for ground fault protective relays. Effects of frequency-selective grounding on ground fault protection are experimentally evaluated using a 7.5 kVA synchronous generator. Experimental tests are conducted for different implementations of ground fault protection, when responding to fault and non-fault events. Evaluation results detailed in this paper demonstrate the negligible effects of frequency-selective grounding on responses of different ground fault protective relays.

Original languageEnglish
Pages (from-to)1-13
Number of pages13
JournalIEEE Transactions on Industry Applications
Publication statusAccepted/In press - 2022


  • and ground fault protection of synchronous generators
  • Frequency-selective grounding
  • Grounding
  • Harmonic analysis
  • Impedance
  • power system faults
  • Power system harmonics
  • Resistance
  • Stator windings
  • Voltage measurement

ASJC Scopus subject areas

  • Control and Systems Engineering
  • Industrial and Manufacturing Engineering
  • Electrical and Electronic Engineering

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