## 4 Simulation Results and Analyses
### Results and Analyses
#### 4.2.3 Simulation Results and Analyses for 8:00 to 17:00  
Figure 12 shows the results of the period 8:00-17:00 taken from Figure 7. During 8:00-17:00 the PV generated power is variable according to the solar irradiation. The PV generated power is less than the load demand power from 8:00 to 9:30 and then it severely changes around the load demand power until 14:10. From 14:10 to 17:00, the PV generated power is often greater than the load demand power. Sub-flowchart a operates when the PV generated power is less than the load demand power. The BS has the higher priority to supply the \(\Delta p\) to keep the power balance of the microgrid; then, when the BS has no more power, the DG is turned on because the public grid is predetermined with a low limitation, and the PV cannot support 80% of the load demand power. Otherwise, when the PV generated power is greater than the load demand power, the BS recharges until the \(soc_{BS}\) reaches the \(SOC_{BS}\_MAX\) and the excess power is sold to the public grid under the fixed limitation of \(p_{G}\_MAX\); if PV sources generate too much power, the PV shedding occurs to keep the power balance in the microgrid. During the period 8:00-17:00, the DG is also turned on at 9:58, 11:18, and 12:27 and shows the same results as those depicted above at 6:27. Figure 13 shows the curve of the common DC bus voltage and the SOC curves of the SC and BS, and Figure 13 shows the power curves when the load starts shedding at 10:42. In Figure 13, the load starts shedding at 10:42 according to case 7 of sub-flowchart a because the microgrid generated power cannot supply the load demand, and the load can be shed less than its non-critical load. Due to load optimization, the optimal load combination result can be such that \(p_{G}\) is under \(-p_{G}\_MAX\), meaning that the public grid cannot supply its maximal power to the microgrid. Figure 12: Curves of common DC bus voltage and SOC of storage (**a**) and curves of power (**b**) during the period 8:00–17:00. For an easy reading of Figure 13a,b, the same points are marked in both figures and the given numerical values only reserve the integer part. These values show that the DC bus voltage is stable, the PV is working in MPPT mode, the load works in its load shedding mode, the BS is not working because the \(soc_{BS}\) reaches the \(SOC_{BS\_MIN}\), and the public grid supplies power to the microgrid. The DG and SC are not working because the load power shedding does not reach its critical limit. Figure 14a shows the curve of the common DC bus voltage and the SOC curves of the SC and BS, and Figure 14b shows the power curves when the PV starts shedding at 12:45. Figure 14: Curves of common DC Bus voltage and SOC of storage (**a**) and curves of power (**b**) during PV shedding. Figure 13: Curves of common DC bus voltage and SOC of storage (**a**) and curves of power (**b**) during load shedding. Because the PV sources generate more excess power than the microgrid needs, in Figure 14, the PV generator is shedding in five periods noted as Period 1, Period 2, Period 3, Period 4, and Period 5 according to case 1. The DC bus voltage fluctuation is caused by the dynamic response of the PV shedding control loop. For an easy reading of Figure 14a,b, the same points are marked in both figures and the given numerical values only reserve the integer part. The marked values show that the PV works in the PV shedding mode, the load works at its load demand, the BS is not working because the \(soc_{BS}\) reaches the \(SOC_{BS\_MAX}\) meaning the BS is full, and the microgrid sells the excess PV power to the public grid at \(p_{G\_MAX}\). One notes that the DG and SC are not working because the PV power covers enough of the load demand. During the period 8:00-17:00, PV shedding also happens at 14:51, and 15:44 and shows the same results as those depicted above at 12:45. Figure 15a shows the curve of the common DC bus voltage and the SOC curves of the SC and BS, and Figure 15b shows the power curves when the SC starts recharging at 9:33.