Revised load shedding schedule for power system incorporating the effect of transmission line performance

There is a growing trend towards the use of sophisticated relays like frequency trend relays for the purpose of automatic load shedding to avert the major system collapses due to integrated operation of modern power system. Accurate load shedding saves loss of revenue to power utility in addition to avoiding unnecessary disruption of vital feeders. Face values of NW capacities of generation outages are normally used for estimating the system overloading and consequent quantum of load shed to recover the system to safe workable frequency. Inherent dependence of transmission line parameters upon the system frequency affects the line performance in terms of its reduced output during under-frequency condition. The paper has attempted to present a modified load shedding scheme incorporating the relieving effect of transmission network and showed the advantages over the conventional method. (C) 2002 Elsevier Science Ltd. All rights reserved.