US 12,461,171 B2
Single phase broken conductor detection
Yanfeng Gong, Dublin, OH (US); Normann Fischer, Colfax, WA (US); Gandhali P Juvekar, Mountlake Terrace, WA (US); and Kanchanrao Gangadhar Dase, Pullman, WA (US)
Assigned to Schweitzer Engineering Laboratories, Inc., Pullman, WA (US)
Filed by Schweitzer Engineering Laboratories, Inc., Pullman, WA (US)
Filed on Nov. 7, 2023, as Appl. No. 18/503,273.
Prior Publication US 2025/0147123 A1, May 8, 2025
Int. Cl. H02H 7/00 (2006.01); G01R 31/54 (2020.01); H02H 1/00 (2006.01); H02H 6/00 (2006.01)
CPC G01R 31/54 (2020.01) [H02H 1/0007 (2013.01); H02H 6/00 (2013.01)] 24 Claims
OG exemplary drawing
 
1. A system to detect a fault in an electric power system, the system comprising:
an intelligent electronic device (IED) to receive a plurality of measurements over time of a current through an electrical conductor in the electric power system;
a fault detection subsystem to monitor for a broken conductor condition and configured to:
determine a zero-sequence current based on the measurements of the current;
determine a negative-sequence current based on the measurements of the current;
determine a positive-sequence current based on the measurements of the current;
determine a ratio of the zero-sequence current, the negative-sequence current, and the positive-sequence current;
monitor the ratio over a time; and
identify the broken conductor condition based on the ratio; and
a protective action subsystem to implement a protective action based on identification of the broken conductor condition.