Page 125 - IJEEE-2022-Vol18-ISSUE-1

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Fig.17: Voltages and frequencies of Bus-600V and PCC with phase difference in first case

Fig.18: Percentage of negative sequence in first case.

B. In second case study, the grid-following and grid- The solar irradiation is constant at 650 W/m2 and also
forming are demonstrated. To reconnect the M-grid with the the boost duty ratio is near 0.35 with boost output voltage,
PV voltage and current are shown in Fig.20. In Fig.21 the
distribution system, a resynchronization to the grid is microgrid's frequency is kept constant at 50Hz, with a phase
difference depicted in the same figure. The microgrid
undertaken. The adopted system functions in grid following reconnects to the main grid at time point (9 seconds), and the
frequency is exactly 50Hz, with no phase difference. Fig.22
mode for the first 1 second, then in islanded mode after that shows the negative sequence value in the second case study.

as shown in Figs 19-21. Figure 19 shows that the main grid
power at PCC is zero (M-grid in islanded mode) in the time

interval [1-5] sec. Otherwise its operates in grid following

mode.