Research on Under-Voltage Load-Shedding to Prevent Voltage Collapse of Electric Power System

A voltage collapse is defined as the process by which voltage instability leads to a very low voltage profile in a significant part of the system. Under-voltage load-shedding is an efficient scheme to prevent voltage collapse. The paper analyses the mechanism of under-voltage load-shedding preventing voltage collapse, compares distributed load-shedding scheme with centralized scheme, introduces under-voltage load-shedding scheme employment at home and abroad, points out that how to work out a proper plan to efficiently prevent voltage collapse, select the time steps, site and amount of load-shedding lies on the conditions of the special power system itself.