Effective transient stability assessment based on composite indices

This paper presents a new composite index to analyze power system transientstability. contingency ranking in power system transient stability is a complicated and timeconsuming task. to prevail over this difficulty, various indices are used. these indices arebased on the concept of coherency, transient energy conversion between kinetic andpotential energy and three dot products of the system variables. it is well known that someindices work better than others for a particular power system. this paper along with testresults using two practical 230 kv sistan and 400 kv khorasan power system in iran, and 9bus ieee test system demonstrates that combination of indices provides better ranking thana single one. in this paper two composite indices ( ci ) is presented and compared. onecomposite index is based on least mean square algorithm (lms) and other based onsumming indices by equal weights. numerical simulations of the developed index,demonstrate that composite index is more effective than other indices.