*6.1. Case 1: Constant Weather Conditions*

6.1.1. PVW 752 Cell

The proposed HGTO-BWO was employed to determine the parameters of the DDM and TDM for a PVM752 GaAs thin film cell at 25 ◦C and 1000 W/m2; the electric characteristics of the PVM752 cell and the measured *I*-*V* data are presented in [74]. The convergence curves obtained by the considered optimizers for both models are shown in Figure 5. The

RMSE value, statistical analysis, and optimal parameters of the DDM obtained through the proposed HGTO-BWO in comparison to the others are illustrated in Table 5. The least obtained RMSEs for the DDM and TDM were achieved by HGTO-BWO with values of 2.0886 × <sup>10</sup>−<sup>4</sup> and 1.527 × <sup>10</sup>−4, respectively. On the other hand, the GTO approach ranked second, achieving fitness values of 4.6815 × <sup>10</sup>−<sup>4</sup> for the DDM and 2.278 × <sup>10</sup>−<sup>4</sup> for the TDM. The HS algorithm was the worst approach; it provided fitness values of 6.6870 × <sup>10</sup>−<sup>1</sup> for the DDM and 3.738 for the TDM. Figure <sup>6</sup> shows the estimated and measured *P*-*V* and *I*-*V* curves of the DDM and TDM. It is notable that the estimated curves converge closely with the measured data; this means the PV cell/panel performed well and converged with the real one. The statistical parameters including best, worst, mean, and std are shown in Figure 7. The results shown in Table 5 verify the effectiveness of the suggested approach in extracting the parameters with the least fitness values compared to the other algorithms. The values given in bold indicate the best solutions obtained by the proposed HGTO-BWO approach.

**Figure 5.** Convergence curves for PVW 752: (**a**) DDM and (**b**) TDM.

**Figure 6.** Measured and determined *I-V* and *P-V* curves for the PVM752 cell: (**a**) DDM and (**b**) TDM.


**Table 5.** Optimal parameters of PVW752 PV cell DDM and TDM models.

**Figure 7.** Bar chart of statistical analysis for the PVM752 cell: (**a**) DDM and (**b**) TDM.
