*1.1. Literature Review*

The paper is a survey of the most recent research publications with the goal of identifying important research gaps. [10–31]. We examined several PV array topologies for consistency, stability and easy implementation.

The authors in [10] observed the effects of PV faults on the power grid under various faulty conditions using the MATLAB/Simulink-based study. A comprehensive analysis is investigated in terms of power at GMPP with selected SP, BL, TCT and reconfigured methodology (RM) configurations as 3.99 kW, 4.01 kW, 4.6 kW and 5.02 kW. In [11], an auto-reconfiguration approach is performed through switching-based PV array electrical connections from SP to TCT under PSCs. For shading pattern-1, the power at GMPP of conventional setups (SP and TCT) is 25.22 W and 26.19 W, respectively. In addition, PL values are observed for SP and TCT configurations under similar shadowing conditions as 3.75 W and 2.78 W. In [12], a detailed study is carried out with various PV array interconnections, including SP, HC and TCT. In the adopted PV array interconnections, power at GMPP of existing setups (SP, HC and TCT) is found as 4.39 kW, 4.44 kW and 4.72 kW, respectively. It is observed that the TCT configuration has a higher rating compared to conventional configurations. The authors of [13] presented a comprehensive study to mitigate shading effects, a novel LS-puzzle-based configuration compared to the TCT configuration. Locations of GMPP for shading pattern-1 exist as 1976 W and 2279 W. During all shading cases, Latin square—TCT (LS-TCT) has the best performance compared to TCT configuration. The Futoshiki puzzle (FP) is investigated in [14] and obtained results show that the power produced by the FP configuration is highest and minimized ML under various shading instances. Power generated as 40.07 W, 53.93 W and 53.93 W in TCT, EAR and Futoshiki configurations for a short wide (SW) shading scenario. For a long narrow (LN) shading condition, the generated power at GMPP is 59.41 W, 60.56 W and 60.56 W. In [15], the authors developed a novel method to reconfigure the PV module's interconnection and compared it to the TCT configuration. The behavior of the P-V characteristic generated from the reconfigured PV array is found to be smoother than that of TCT-configured PV arrays under-considered PSCs. The half-reconfigured PV array (HRPVA) and full-reconfigured PV array (FRPVA) have increased the coherence between the obtained GMPP. With a performance ratio of 0.93, the generated power increased by 14.75% in HRPVA. Furthermore, with a unity performance ratio, FRPVA enhanced generated power by 23.3%. The proposed MS configuration in [16] is tested using a 3 × 3 PV array coupled to the TCT pattern under SN, LW, LN and SW shadowed conditions. TCT and MS configurations are investigated under SN shading scenarios, with GMPP locations of 1.8576 kW and 2.3734 kW being observed, respectively. For the shading pattern subjected to LN, the GMPP locations are assessed as 2.4278 kW and 2.8849 kW, respectively. The authors of [17] investigated the PV array arrangements, e.g., SP, TCT, BL, HC and hybrid series parallel-total cross tied (SP–TCT) and BL–TCT, and game-puzzle-based configurations such as nonsymmetrical-1, 2 (NS-1 and NS-2) are reported. The shading pattern-3 subjected to TCT array configuration has power at GMPP as 5260 W, 4545 W, 4332 W, 4182 W for four distinguished shading cases, respectively. In a similar shading scenario, the NS-2 configuration has power levels at GMPP locations of 5260 W, 5013 W, 4811 W and 4182 W, which are higher than conventional methods.

In [18], the performance of PV array designs of 4 × 4 sizes, i.e., MATLAB/Simulink is used to investigate TCT, hybrid SP-TCT, BL-TCT, BL-HC and MS, RSP-TCT, RBL-TCT and RBL-HC. The power at GMPP is observed as 2279 W, 1976 W, 2279 W, 1976 W, 2197 W, 1976 W, 2233 W, 1976 W and 2255 W for the respective topologies. The authors of [19] analyzed TCT configuration for performance improvement under PSCs. The power at GMPP under shading case-4 is observed as 377.2 W, 468.9 W and 468.9 W for TCT, Optimal TCT and Novel TCT configurations, respectively. Performance indices such as FF are observed at 40.46%, 60.26% and 60.28%, respectively. The authors of [20] discussed the result and test conducted on a 4 × 5 size PV array configuration with distinguishing shading scenarios. The power at GMPP for shading scenarios is observed as 797.24 W, 823.75 W, 819.22 W, 850.25 W, 851.57 W for SP, BL, HC, TCT and Novel PV array topologies. Furthermore, the calculated PL are found as 1.88%, 4.13%, 2.32%, 2.59% and 1.30%, respectively. The authors of [21] proposed a shade dispersion scheme (SDS) arrangement compared to other conventional PV module interconnections such as SP, BL and TCT under realistic shading patterns. The power at GMPP of PV array for SP, BL, TCT and SDS configurations is 1644.36 W, 1689.84 W, 1721.55 W and 1746.33 W, respectively. Also, results in PL for the same are 301.40 W, 256.12 W, 224.41 W and 199.63 W. The SDS configuration has a higher performance among all the PV array configurations. In [22], the recently developed cross diagonal view (CDV) configuration is proposed and compared to the conventional SP and TCT configuration for a 9 × 9 size PV array module. The power at GMPP is observed for SP, SDK, TCT and TCT-CDV as 6307.5 W, 6307.5 W, 4861.2 W and 7492.5 W. In [23], new physical PV array setups are introduced to reduce the shading impact and generated power at GMPP for SP, TCT and modified TCT (M-TCT) configurations under the considered shading conditions 174.60 W, 185.33 W, 215.74 W and 523.80 W, respectively.

Interconnection methods are proposed in [24] to reduce PL during PSCs. The TCT and proposed configurations have increased the power output by 7.8% and 6.9% compared to the conventional SP arrangement. The GMPP locations are found as 4065.3 W, 4419.3 W and 4393.1 W for SP, TCT and proposed topologies, respectively. The authors of [25] calculated the comparative result in terms of maximum power for parallel and series configurations under distinguished shading effects as 544.2 W, 492.45 W, 381.1 W and 446.5 W. For minimizing the shadowing effect, the parallel configuration is convenient. In [26], SDK arrangement was compared to TCT and validated experimentally on a 5 × 5 size array. Power of 266.4 W and 280.2 W was generated for the proposed Su-Do-Ku and TCT configuration subjected to two types of PSCs. People who came up with this idea say it makes P-V curves more even and eliminates the MPPT algorithm as well as the financial risk. In [27], the authors proposed a column-index-based topology for PV reconfiguration scheme. The generated power at GMPP for PV array topologies was such as proposed, DS, TCT and SP are 5338 W, 5101 W, 5066 W and 4815 W under LN-based shading pattern. The proposed technique was tested on a 9 × 9 size PV array and the results showed that it increased the global maximum power when compared to DS, TCT and SP array configurations.

In [28], the I-SDK arrangement enhanced the global power peaks (28.6%, 22.1%, 22.8%, 17.2%, 6.2% and 5.2%) compared to conventional (SP, BL, HC, TCT) and puzzle-based (SDK and optimal SDK) PV array setups under a realistic shading scenario. The authors of [29] designed 6 × 4 size PV array setups for performance investigation under shading scenarios. The SP, TCT, BL, HC, BL-HC, BL-TCT and SP-TCT arrangements were adopted for performance investigation and the generated power at GMPP was observed as 2177 W, 2394 W, 235.2 W, 2235 W, 2187 W, 2389 W, 2306 W and 2298 W, respectively. Moreover, TCT and BL-TCT configurations have shown a better response in terms of the highest power at GMPP, minimum PL and improved FF. The authors of [30] reviewed the performance of the proposed SRBL-TCT configuration compared to SP, TCT, BL, HC and BL-TCT results obtained under the realistic moving clouds phenomenon. At each of the five shading instants, the obtained GMPP location of the SRBL-TCT configuration was found to be superior to the SP, TCT, BL, HC and BL-TCT configurations. The obtained power at GMPP for the BL-TCT PV array configuration subjected to all five shading scenarios was 39.57 W, 23.89 W, 38.85 W, 38.05 W, 26.5 W. In the SRBL-TCT PV array configuration, the power at GMPP for all five considered shading scenarios as 44.31 W, 38.63 W, 42.44 W, 41.04 W and 40.93 W, respectively. The skyscraper methodology was simulated along with its application to a 9 × 9 size PV array and was matched to the TCT, DS and SDK arrangement using MATLAB/Simulink in [31]. Under PSCs, the PL for skyscraper, TCT, DS and SDK was 0.305%, 0.35%, 0.325% and 0.316%.
