## 5 Simulation Experiments, Verification, and Comparative Analysis
It implies that the overall architecture takes the form as shown in Figure 3b. * An important point can be noted from the \(I_{pv}\) curves that in the moderate shading case, i.e., the MS-case in Figure 8b, the mismatch between \(I_{M2}\) and \(I_{string}\) is lower compared to the strong shading case, i.e., the SS-case in Figure 9b. As a result, the controller sets the higher \(D\) and lower \(D\) values for the MS-case and SS-case, respectively, as can  
Figure 7: Three different shading cases: (**a**) single module moderate (15%) shading level, i.e., M2 at 850 W/m\({}^{2}\)–20 \({}^{\circ}\)C, (**b**) single module strong (50%) shading level, i.e., M2 at 500 W/m\({}^{2}\)–15 \({}^{\circ}\)C, and (**c**) double module extreme (75%) and moderate (25%) shading levels, i.e., M2 at 250 W/m\({}^{2}\)–10 \({}^{\circ}\)C and M1 at 750 W/m\({}^{2}\)–20 \({}^{\circ}\)C.  
be seen from the graphs of both Figures 8d and 9d. Naturally, the \(V_{M2\_buck}\) curve of the MS-case is in close proximity to the \(V_{M1}\) and \(V_{M3}\) voltage curves of modules M1 and M3, respectively, as shown in Figure 8c. Because of this, the inverter makes only a minor adjustment in its DC-link voltage, as indicated in Figure 8e. In contrast, the \(V_{M2\_buck}\) curve of the SS-case is at quite an offset from the \(V_{M1}\) and \(V_{M3}\) voltage curves of modules M1 and M3, respectively, as illustrated in Figure 9c. Naturally, the buck converter operates at quite a different \(D\) value to bridge the gap. Therefore, the inverter also makes more adjustments in its DC-link voltage, as shown in Figure 9e. These two simulation results, i.e., Figures 8 and 9, depict excellent resemblance to the theoretical study that is presented in Figure 4a,b, respectively. Importantly, these results clearly highlight the correct and efficient operation of the proposed architecture. Figure 10 displays the response of the proposed architecture when two modules (M1 and M2) of PV string are under the influence of partial shading, i.e., the extreme shading case, as shown in Figure 7c. The timeline is set as follows: (1) from 0 to 30 ms, all modules are under STC; (2) from 30 ms to 50 ms, only M2 is under the influence of 250 W/m\({}^{2}\)-10 \({}^{\circ}\)C; and (3) from 50 ms onward, M1 and M2 are under the influence of 750 W/m\({}^{2}\)-15 \({}^{\circ}\)C and 250 W/m\({}^{2}\)-10 \({}^{\circ}\)C, respectively. Figure 10d shows that the current equalizer manager of the  
Figure 8: Response of the proposed architecture when a PV array is under the influence of the Figure 7a shading case, with sub-graphs: (**a**) \(P_{pv}\) curves of all modules, (**b**) \(I_{pv}\) curves of all modules and output current curve of the M2 buck converter, (**c**) \(V_{pv}\) curves of all modules and output voltage curve of the M2 buck converter, (**d**) \(D\) signals of the buck converters of all modules, and (**e**) DC-link voltage controlled by the centralized MPPT inverter. proposed architecture activates the duty cycle operation of the buck converters of M2 and M1 one-by-one after 30 ms and 50 ms, respectively. The \(D\) values are different as M2 and M1 are under different shading conditions. It can be confirmed from Figure 10b that even under this extreme shading case, the proposed architecture manages to make the output current of M2 (pink color) and output current of M1 (brown color) of the buck converters equivalent to \(I_{string}\). However, because of extreme shading, the centralized inverter makes a considerable adjustment in \(V_{DC\_link}\) voltage as shown in Figure 10e. The proposed architecture contains a converter for each module. The appropriate fabrication and operational management of each converter in terms of its thermal management, devices operation, and high efficiency are critical. Additionally, for large-scale PV plants, the effective management of multiple converters also poses a sizable challenge. Finally, the advanced control schemes can be utilized for the optimized control of converters [31].