Identification on Vulnerable Lines of Power Grid in View of Voltage Grade and Running State
Xin Lü · Guangdong Electric Power · 2014
For reasonable evaluation on vulnerability of power grid,concept of flow entropy for measuring imbalance distribution of flow was introduced and index for identifying vulnerable lines by means of change of flow entropy was proposed in the case of considering real-time running state of the power grid.On the basis of complex network theory and in view of characteristics of topology structure of the power grid,node importance index was established and vulnerability correction factor was proposed by combining voltage grades and geographic position of lines.By synthesizing change of flow entropy,node voltage excursion,node importance and correction factor,method for identifying vulnerable lines of city power grid was proposed.Taking heavy load running mode in summer in 2011 of some city power grid as an example,analysis on vulnerability of lines and time-domain simulation verification was carried out.Simulation result indicated that this method was able to well identify vulnerable lines in city power grid especially those important connecting lines undertaking few power which was identical to practical running state of the power grid.Identification on vulnerable lines of IEEE-39 node system stated reasonability and universality of the proposed method.