Application of pulse based power line carrier permissive (PLCP) in distribution system islanding detection

Power line carrier permissive (PLCP) is a promising communications-based islanding detection scheme that could provide reliable detection of unintentional islands for any combination or penetration level of distributed generation on a feeder. National Grid is conducting demonstration activities of this new technology to assess how well the reality aligns with the promise. One candidate demonstration site has been selected, but before the demonstration could proceed, the site had to be studied to assess: a) the existing risk of formation of an unintentional island; b) the fault current contribution expected from the new proposed distributed generator; c) the possibility that the PLCP signal may create power quality issues, especially flicker; and d) whether the proposed PLCP signal will be visible at all DG sites on the candidate feeder. A simulation study was conducted to make these assessments, and this paper reports on the results of that study, and the applicability of PLCP to this feeder.