Leveraging existing relays to improve single phase auto-reclosing

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Department of Electrical and Computer Engineering


Single-phase auto-reclosing (SPAR) is used in power systems worldwide. However, many SPAR methods do not present a practical approach for field implementation. Although manufacturers have embedded SPAR functions into their commercial relays, the closed solutions make not trivial the application of new functions/methods. Thus, in this paper, a practical approach is proposed to leverage existing relays structure aiming to improve SPAR applications. A simple and effective phasor-based single-phase auto-reclosing scheme for non-compensated transmission lines is embedded in a commercially available relay equipped with a free-form programming logic. Field recordings of single-line-to-ground (SLG) faults followed by single-phase opening of transmission lines are used in a playback test procedure for validation. The results attest the effectiveness of the implemented SPAR method, as well as the feasibility of the proposed practical approach for real-world applications.

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Electric Power Systems Research