“…OPPP solution for 57-bus system using DFS, GTP, SAM, RSNA, and MBBA ,7,9,15,19,21,24,27,30,32,36,38,39,41,46, 50, 52, 54 0.01 GTP 1 21 2, 4, 7, 9, 15, 16, 17, 19, 21, 24, 27, 30, 32, 36, 38, 39, 41, 46, 50, 52, 54 0.02 SAM 1 19 1, 4, 7, 9, 15, 19, 21, 24, 27, 30, 32, 36, 38, 39, 41, 46, 50, 52, 54 13.8 2 18 1, 4, 9, 13, 17, 19, 23, 27, 28, 30, 32, 39, 42, 44, 47, 50, 52, 54 15.3 3 18 1, 6, 12, 15, 16, 19, 23, 29, 30, 33, 34, 43, 44, 49, 50, 53, 55, 56 , 16, 17, 20, 25, 29, 32, 36, 41, 48, 51, 54 1.81 Abbreviations: DFS, depth-first search; GTP, graph-theoretic procedure; MBBA, modified branch-andbound algorithm; OPPP, optimal phasor measurement unit placement problem; PMU, phasor measurement unit; RSNA, recursive security N algorithm; SAM, simulated annealing method.…”