... the form eljt and e(lkþll)t:xi(t) ¼Xnj¼1uijzj0eljtþXnj¼1uijXnk¼1Xnl¼1Cjkllkþ llÀ ljzk0zl0e(lkþll)t"# (9 :2)lk, ll, and ljare the ... J., and Fortin, S., A minimal realization approach to reduced-ordermodeling and modal analysis for power system response signals, IEEE Trans. Power Systems, 8(3 ),1020–1029, 1993.Kundur, P., Power ... design of FACTS controllers to damp power swings, IEEE Trans. Power Systems, 1 0(2 ), 948–956, May 1995.Lee, D.C. and Kundur, P., Advanced excitation controls for power system stability enhancement,...