Field Verification of Secondary Arc Extinction Logic.

Single-phase trip and high-speed reclose (SPTR) schemes applied on extra-high-voltage (EHV) lines offer significant benefits over three-phase schemes as they help maintain synchronism and stability in sparse transmission networks. However, a secondary arc may persist and prevent timely recovery of the air insulation. In this situation, high-speed reclosing will attempt to re-energize the still-faulted line, adding stress to the system instead of benefiting the system from the SPTR scheme. Using staged fault and fault disturbance data recorded from several 500 kV lines, this paper presents validation of an enhanced hybrid scheme incorporating secondary arc extinction detection logic designed to avoid high-speed reclosing onto faults while also allowing single-phase reclose in cases where it would be successful. The new logic is now being applied to several 500 kV lines in BC Hydro to improve transmission system reliability. [ABSTRACT FROM PUBLISHER]