“…Among them, when V o = 0.0650, the optimal clustering result can be obtained for the AFR control (as shown in Figure 8), and the number of the coherent groups is six. 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29} 0.0767 4 {1}, {2, 3,4,5,6,7,8,9,10,12,13,14,15,17,18,19,20,21,22,24,25,26,27,28 When the number of the coherent groups of the generator buses on the 500-kV grid structure of the Henan power grid is six, the AFR control effects with and without the clustering control are shown in Figure 9. As demonstrated in the simulation results, under the AFR control, if the clustering control is not adopted, the frequency nadir and the transient maximum frequency of the Henan power grid are 49.5093 Hz and 50.2918 Hz, respectively.…”