1. Introduction
In recent decades, interest in renewable energy sources has become very large due to environmental concerns resulting from fossil fuel pollution, global warming, solid waste, the dangers of burning coal, and the instability of fossil fuel prices. Many alternative energy sources have been found to avoid this, such as wind, water, solar energy, and others. Moreover, solar energy is considered one of the most important energy sources for generating electricity due to its high availability, safe and pollution-free manufacturing methods, and noise-free manufacturing methods. In addition, the price of solar cells has decreased in recent years.
The popularity of solar photovoltaic (PV) systems has increased nowadays because of their use of solar cells [
1]. These technologies’ ability to convert solar energy into electricity is impressive. In order to regulate and optimize PV systems, it is crucial to build a precise model that incorporates observed current-voltage data, as this enables the evaluation of the PV array’s actual behavior. Several mathematical models have been developed to shed light on the performance and nonlinear features of PV systems [
2], with single-diode and double-diode setups being the most common and commonly used.
The reliability of the parameters is intrinsically tied to the accuracy of the photovoltaic (PV) models. However, environmental variables such as temperature, global irradiation, material flaws, and shifting operational conditions make it difficult to consistently achieve these requirements. Therefore, accurate models that outline the complex relationship between current and voltage are required for the optimization and control of PV systems [
3]. In recent years, numerous parameter identification approaches have been developed to meet this pressing requirement [
4].
Recently, numerous strategies for finding the parameters of photovoltaic (PV) models have been put forward as potential solutions. They can generally be divided into the following three categories: (1) analytical methods, which are mainly based on the short circuit point, open circuit point, and maximum power point; these methods are fast, simple, and unique, but they are not accurate [
5,
6,
7,
8,
9,
10,
11]. (2) Deterministic methods. These methods are sensitive to the initial values and require a level of calculus and convexity. However, they are still not precise enough in the same manner as Newton’s approach [
12], the Newton–Raphson approach [
13], or the method of the nonlinear algorithm [
14]. (3) Meta-heuristic methods are a promising and powerful solution to extract the parameters of the photovoltaic model, and because they are easy to implement and most of them are inspired by the phenomena of nature, they do not need convexity conditions or the derivation of the objective function. Despite developing a set of optimization algorithms, they fail to provide satisfactory results, so meta-heuristic algorithms have been used to solve difficult and complex problems [
15].
Consequently, many metaheuristic algorithms have been developed and applied in many fields and to extract the parameters of photoelectric models. The parameters of the diode model of a polycrystalline solar module cell were extracted using the moth optimization algorithm [
16], the genetic algorithm (GA), which was derived from Darwin’s development theory [
17], particle swarm optimization (PSO) [
18], simulated annealing algorithm (SA) [
19], artificial bee colony (ABC) [
20], anarchic asexual reproduction (CARO) [
21], multiple learning backtracking search (MLBSA) [
22], cuckoo search algorithm (CS) [
23], biogeography optimization (BBO) [
24], MBO algorithm [
25], sunflower optimization algorithm (SFO) [
26], coyote optimization algorithm (COA) [
27], Bacterial Foraging Optimization (BFO) [
28], Harris haws optimization (HHO) [
29], and modified flower algorithm (MFA) [
30].
As a direct consequence of this, efforts are currently being undertaken to create more effective optimization algorithms to calculate the parameters of solar photovoltaic cells [
31,
32]. In the next parts, an in-depth discussion on optimizing photovoltaic systems will be held, focusing on previously developed and evaluated methods.
The algorithms discussed earlier have been applied to various topics, and their results have been found to be satisfactory. However, according to the No Free Lunch theorem [
33], there is not yet a superior method of optimization in all circumstances. Furthermore, many optimization methods have benefits and drawbacks that are comparable to one another [
34,
35]. These approaches, for instance, have a substantial benefit in that they can handle a diverse range of systems with nonlinear fitness functions and restrictions [
36]. This is just one example. The primary drawbacks include difficulty adjusting their parameters, the potential for early convergence, the inability to find global optimal solutions, the lack of diversity, and the instability in balancing exploration and exploitation in the solution space [
37,
38]. These drawbacks can be overcome, however, by using alternative approaches. These methods, if developed with care, have the potential to provide extraordinary performance and versatility for solving difficult optimization problems in the real world [
39,
40].
As per the No Free Lunch theory, existing optimization algorithms have limitations and weaknesses [
41,
42,
43,
44] and may not be suitable for all types of problems. Thus, there is still potential for improvement in algorithm efficiency. Recent studies have focused on developing new ways to improve fundamental optimization procedures by integrating a variety of initial design strategies [
45,
46,
47], hybridizing optimization procedures [
48,
49], and altering search patterns [
50,
51,
52,
53,
54]. The Gradient-based Algorithm (GBO), a population-based optimization technique, is an exciting new discovery made very recently. This technique has demonstrated that it is effective and precise in its optimization outcomes. During the phase of exploration and exploitation, GBO uses the information that is available to find optimal or near-optimal solutions by randomly selecting two solutions from the population to predict future relocation and direction based on the best search options. This helps GBO find the best possible options. However, it has been discovered that the new optimization method of GBO has significant drawbacks in high-dimensional and multimodal problems. These drawbacks include getting stuck in local solutions as the size of the search space increases and having poor convergence performance in difficult problems [
55,
56].
Additionally, the characteristics of the objective function have the potential to have a negative impact on the performance of the algorithm in specific contexts. Particularly when dealing with issues that include many modes of communication, the search method may be hampered. It is well known that the objective function for Solar Photovoltaic Parameter Estimation problems is multimodal and nonlinear with multiple local minimums. Because of this, it is challenging to develop new robust optimization techniques that can produce more accurate and faster convergence results.
This study aims to find the best values for the parameters of Photovoltaic systems. To achieve this, this study proposes a modified gradient search rule (MGSR) based on the quasi-Newton method, derives the MGSR factor that controls vector motion to improve its local and global capabilities, and enhances exploration to improve the search in the selected area. In addition, a new refresh operator (NRO) has been proposed to enhance the algorithm’s solution quality and exploration abilities, as well as a strong crossover mechanism to balance exploitation and increase population diversity. The proposed method, MAGBO, is tested for its performance on CEC2021 benchmark functions and a complex Photovoltaic system. The results are compared with various optimization methods such as Gradient-based Algorithm (GBO), Gradient-based optimization with ranking mechanisms (EGBO), Slime mould algorithm (SMA), Self-adaptive differential evolution algorithm (SADE), Equilibrium optimizer (EO), new self-organizing hierarchical PSO with jumping time-varying acceleration coefficients (HPSO_TVAC), comprehensive learning particle swarm optimizer (CL-PSO), Improved Jaya Algorithm (IJAYA), performance-guided JAYA algorithm (PGJAYA), and multiple learning backtracking search MLBSAs, which shows that MAGBO outperforms the other methods in this context. The Wilcoxon rank-sum and Friedman statistical tests are used to confirm the validity of MAGBO.
The heart of this research revolves around the advanced development and meticulous validation of the MAGBO technique, tailored for photovoltaic system parameter identification. Specifically:
Modified Gradient Search Rule (MGSR): utilizes the quasi-Newton method to bolster both local and global optimization.
Crossover Mechanism: introduced to ensure greater agent diversity and prevent premature convergence.
Novel Refresh Operator (NRO): enhances solution quality and strategic exploration, balancing exploration and exploitation.
Rigorous Validation: comprehensive evaluation of various SDMs, DDMs, and PV modules, showcasing MAGBO’s superiority over older methods.
To organize the remainder of this paper, the second section focuses on MAGBO’s related work. The original GBO and problem statement are presented in
Section 3.
Section 4 explains the details of the proposed MAGBO. In
Section 5, experimental results and comparisons are presented.
Section 6 discusses the problematic constraints and difficulties, and finally,
Section 7 concludes with the conclusions and future work.
5. Computer Results and Simulations
In this section, the primary objective centers around an in-depth examination of the newly proposed MAGBO algorithm. To ensure a comprehensive analysis, we juxtapose MAGBO against several state-of-the-art algorithms, utilizing the challenging functions from the IEEE CEC 2021 test suite. This rigorous benchmarking offers a solid foundation for assessing MAGBO’s optimization capabilities. To supplement the numerical findings, the Wilcoxon signed-rank test, a robust statistical method, is incorporated, lending further weight to the comparative performance claims. Additionally, a qualitative review delves into the intricacies and unique advantages inherent in the MAGBO algorithm. Further fortifying our analysis, MAGBO is applied to the practical task of solar photovoltaic model parameter identification, the results of which are scrutinized through statistical outputs and convergence curve presentations. In the subsequent
Section 6, we transition to an introspective reflection on potential challenges and limitations faced during our research, ensuring that the reader is provided a balanced and holistic view of our work, while also hinting at avenues for future improvements.
All of the evaluations for this investigation were carried out on a personal computer operating under the Windows operating system and including a 2.50 GHz Intel Core i5-7300U processor along with 8 gigabytes of random-access memory (RAM). Python was utilized in the implementation of both MAGBO and its rivals.
MAGBO’s efficiency was evaluated concerning shifted, rotated, and biased functions using the IEEE CEC 2021 test suite in 20 dimensions. This was done so that MAGBO’s performance could be thoroughly investigated by comparing it experimentally to that of rival algorithms. Additional details on the IEEE CEC 2021 test suite may be found in [
76].
The experimental data used for the statistical analysis were obtained by carrying out 30 sets of replicated runs, each consisting of 2500 iterations. The MAGBO algorithm will terminate once the maximum number of iterations has been completed. We evaluate the algorithm’s performance by comparing the average solution (Avg), the median solution (Med), and the standard deviation. All of this is done without compromising generality (std).
In order to investigate the results of both the MAGBO and the competitors, a pair of non-parametric statistical hypothesis tests called the Friedman test and the Wilcoxon signed-rank test are utilized. The Wilcoxon signed-rank test is used to compare the performance of MAGBO and its competitors across several different metrics, such as how effectively they handle specific tasks, to draw conclusions about which of the two is the superior option. In addition, the Friedman test’s final rankings for algorithms on all functions can be used to examine the substantial differences in overall performance between different algorithms.
The effectiveness of the MAGBO is analyzed and compared to that of eight other algorithms throughout the course of this research project. These techniques include GBO [
17], EGBO [
77], SMA [
78], PSO [
79], EO [
80], SADE [
81], CL-PSO [
82], and HPSO_TVAC [
83]. In this section, we have decided to adhere to the suggestions made by the authors of those other publications concerning the important aspects of competition, and we have outlined them in
Table 3.
5.1. Comparison of MAGBO with State-of-the-Art Competitors Using the IEEE CEC 2021 Test Suite
MAGBO was thoroughly evaluated using the IEEE CEC 2021 test suite, and its results were compared to those of eight other algorithms. The results, shown in
Table 4, indicate that MAGBO performed well in terms of average values for most of the test functions, except for f5, f7, and f10. In terms of standard deviation, MAGBO performed significantly better than the other algorithms in almost all cases. These results suggest that MAGBO is a stable, robust, and scalable optimization algorithm that performs well compared to the other algorithms included in the comparison.
The results of the Wilcoxon signed-rank test, which was conducted with a significance level of 0.05, are summarized in
Table 5. These results show that MAGBO outperformed several other algorithms, including HPSO_TVAC, CL-PSO, and PSO, in all CEC 2021 test functions. In addition, MAGBO outperformed EGBO, GBO, SMA, and EO on nine functions and SADE on seven functions. These results suggest that MAGBO is a strong performer among the algorithms included in the comparison.
According to
Table 4, the convergence rate of the algorithm is improved by using a GBO with a crossover mechanism, the NRO local search technique, and a modified gradient search rule based on the quasi-Newton. Together, the presented methods enable the MAGBO algorithm to generate novel solutions by fusing the properties of two or more existing solutions. This increases the likelihood of finding superior solutions by introducing variety into the solution pool. Keeping the algorithm from settling on a locally optimal solution also facilitates exploration and exploitation. Crossover also makes it easier to probe a wider region of the search space. This is of utmost significance in optimization problems involving complicated and rough landscapes, in which the global optimum may be hidden in a previously undiscovered region. Additionally, the MAGBO algorithm seeks to find a middle ground between exploitation (enhancing the best-known solutions) and exploration (looking for new and perhaps superior answers). While some operators, such as mutation, aid in exploitation, the suggested NRO aids exploration by producing more candidate solutions. In addition, the MAGBO algorithm’s convergence can be hastened with the help of a modified gradient search rule based on the quasi-Newton, which may ultimately lead to the generation of superior solutions.
The Wilcoxon signed-rank test showed that MAGBO is a highly reliable optimization technique compared to eight other algorithms.
Figure 6 illustrates the convergence behaviors of MAGBO and its competitors on the CEC 2021 test functions. It can be observed that MAGBO significantly outperforms the other algorithms in both initial and final iterations, indicating that it has strong exploration (using swarm intelligence) and exploitation (using quadratic functions) capabilities. In addition, as shown in
Figure 6, MAGBO can find the global optimal solution and avoid getting stuck in local optima thanks to its new local search feature. This feature allows the algorithm to explore the solution space more thoroughly and find the best possible solution.
5.2. Qualitative Analysis of MAGBO
The researchers in this article combined a multi-strategy—the modified gradient search rule (MGSR) derived from the quasi-Newton method to improve its local and global capabilities, a new refresh operator (NRO) to enhance solution quality and algorithm exploration abilities, and a crossover mechanism to balance exploitation and boost the population’s variety—to create a novel approach (MAGBO) that overcomes the shortcomings of the standard GBO.
MAGBO is a new method for dealing with GBO-related problems such as uneven exploration and exploitation, premature convergence, and population heterogeneity. Functions 1, 2, 3, 8, and 9 are chosen as exemplary examples from the CEC 2021 set for this study. These procedures were picked because they effectively demonstrate both unimodal and multimodal features.
As part of a qualitative study of the system’s performance,
Figure 7 gives an in-depth look at how MAGBO acts when looking for solutions in unimodal and multimodal functions. The graph makes it easy to see where MAGBO stands and how fit it is at any given time during the search. This shows the average global fitness level of MAGBO over the exploration and exploitation phases. MAGBO’s location in the first dimension is also shown on the graph, along with its evolution through time. The variations in MAGBO’s global best fitness (mean) throughout the iterations show how its normal fitness level varies. This visual depiction accurately depicts the research and development stages of MAGBO throughout the entire refinement process.
MAGBO’s primary purpose of exploration is best illustrated by the fact that its first-dimensional trajectory can represent multiple regions of the search space. The MAGBO particle can quickly and correctly find the optimal solution thanks to its rapid oscillation during the prophase and moderate oscillation during the anaphase.
Figure 7b shows that MAGBO’s location curve has a fairly large amplitude early on, which could cover as much as half of the exploration zone. The position amplitude of a MAGBO particle diminishes with time if the function is smooth. However, the position amplitude also shows substantial changes when the function amplitudes are in flux. This exemplifies the flexibility and dependability of MAGBO in many contexts. Depending on the point of view, the changes in amplitude can seem either spectacular or subtle. MAGBO’s substantial early fluctuations attest to the strength of its search skills, while the subtle alterations later on attest to the persistence with which it seeks to locate the ideal solution.
Figure 7c is a graphical representation of MAGBO’s discovery and development processes. The graph has two curves, one blue for the exploration phase and one orange for the exploitation phase of the method. Due to a smaller percentage of exploration relative to exploitation, the initial MAGBO displays a larger exploration ratio, as illustrated in
Figure 7c. However, as the iteration count rises, the algorithm begins to shift its attention from exploration to exploitation for the vast majority of the chosen functions. This continuous pattern guarantees that MAGBO always keeps the right balance between exploration and exploitation.
Figure 7d, which depicts an average global fitness curve, shows that MAGBO’s fitness varies when using the iterative method. The curve has a lot of wiggle room, as can be seen by looking at it closely. The average fitness value drops monotonically with increasing iterations, as does the frequency of oscillation. This indicates that MAGBO searches exhaustively during the anaphase and quickly converges on a solid solution.
The outcomes of diversity analysis on the CEC2021 dataset using the MAGBO algorithm are presented in
Figure 7e. The depicted graph illustrates the relationship between the number of iterations and the diversity measure, with the horizontal axis representing the former and the vertical axis representing the latter. The process commences by initializing the population with a random generation, leading to increased levels of diversity during the initial phases. As the iterations go, diversity gradually decreases. It is important to acknowledge that the CEC2021 dataset has a wide range of functions, including unimodal, multimodal, hybrid, and composition functions.
The visual representation presented in
Figure 7e clearly demonstrates that MAGBO regularly displays a more pronounced decrease in average diversity across different functions. The aforementioned finding indicates the overall accelerated convergence rate of the MAGBO algorithm. Moreover, the findings highlight the general dominance of MAGBO in terms of its performance, making it a viable option for a diverse range of purposes. The primary cause of this phenomenon can be traced to the integration of a “Crossover mechanism” as outlined in Equation (54) within the MAGBO algorithm.
The inclusion of this mechanism in the MAGBO algorithm grants it the capacity to produce innovative solutions through the amalgamation of attributes derived from two or more parent solutions. As a result, the introduction of variation within the population of solutions serves to prevent early convergence and increases the likelihood of finding superior solutions. Furthermore, the integration of crossover facilitates a thorough investigation of the solution space. This characteristic is of great importance in optimization issues that are characterized by complex and uneven terrains, where the global optimum solution may be located in a distant and unexplored area.
However, it is crucial to emphasize that the effectiveness of crossover depends on the particular problem being addressed and the design of the crossover operator. In specific cases, the use of unsuitable crossover operators or parameter settings can hinder the effectiveness of bio-inspired algorithms. Therefore, it is crucial to carefully design and refine every aspect of the algorithm, such as the crossover mechanism, to correspond with the unique characteristics of the optimization problem being addressed.
5.3. The Suggested Approach for Identification of Solar Photovoltaic Model Parameters
In this study, MAGBO is applied to three different models to show its efficiency: the single, double, and PV models. The benchmark data used in this study from [
84] were collected from 36 polycrystalline PV cells and a monocrystalline STM6-40/36 module, both under conditions of 1000 W/m2 irradiation and at different temperatures. These data have been widely used to evaluate different methods for estimating PV model parameters. In previous research, the parameter ranges for PV cells and modules have been kept constant across all studies to ensure a consistent search space. As shown in
Table 6, the parameter ranges for PV cells and modules are provided. Eight algorithms were selected for comparison; the population size N is 30, the maximum frequency is 600 (18,000 maximum evaluation), and the number of independent runs is 30.
5.3.1. The Single-Diode Model
The single-diode module’s current-voltage (I-V) and voltage-current (P-V) curves are displayed.
Figure 8 illustrates the MAGBO mistake that was present on the diode. As shown in
Table 7, MAGBO achieved the best results compared to other algorithms; therefore, it is reasonable to conclude that MAGBO possesses the potential to be an effective instrument for the identification of SDM. In addition,
Figure 9 illustrates the absolute and relative differences in current value that are shown by making a comparison between the data that were simulated and the data that were observed.
The values of five parameters and the RME are presented in
Table 8, demonstrating that the suggested method generates superior results compared to other algorithms already in use. The findings above suggest that the proposed method could be utilized as an efficient approach to the localization of single-diode models (SDM).
5.3.2. Double-Diode Module Results (DDM)
Figure 10 compares the actual observed data and the estimated model properties that MAGBO provided.
Figure 11 presents a graphical representation of a double-diode module’s RE and IAE values. The simulated current-voltage (I-V) and power-voltage (P-V) characteristic curves are an excellent match for the experimental data collected. The simulation results are presented in
Table 9, which includes the current, power, IAE, and RE numbers. The results presented in
Table 9 demonstrate that MAGBO’s double-diode module successfully reproduces the primary properties of solar cells.
Table 10 presents the results of comparisons between the performance of MAGBO and that of alternative algorithms.
Table 10 presents the RMSE comparison findings and the values of the seven extracted parameters taken out of the model. Compared to the other seven methods, the Root Mean Square Error (RMSE) for the suggested MAGBO is as low as possible.
Table 10 presents the results of comparisons between the performance of MAGBO and that of alternative algorithms.
Table 10 presents the RMSE comparison findings and the values of the seven extracted parameters taken out of the model. When contrasted with the other seven approaches, the RMSE for the proposed MAGBO is the lowest it can be.
5.3.3. PV Module (PV)
Figure 12 illustrates the high degree of consistency between the simulated and collected data, with I-V and P-V curves that are realistic approximations of the properties of the Photowatt-PWP 201 module model.
Figure 13 displays the experimentally gathered and computer-generated representations of observed currents for the IAE and RE of the PV module model.
Table 11 presents the findings of this experiment, including the current, power, IAR, and RE values, which support the idea that the values proposed by MAGBO for the model parameters of the PV modules are reliable.
Table 12 lists the best RMSE score and the five extracted parameter values from each of the seven techniques’ total of 30 tests. In conclusion, the proposed MAGBO performs better than other methods in forecasting the parameters of PV module models compared to other methods.
5.3.4. Statistical Results and Convergence Curves
Table 13 provides a summary of the statistical information on competing algorithms. (after carrying out 30 separate runs, each of which consisted of 600 iterations) The statistical data are presented in
Table 13 as best, worst, Avg, std, and Rank values. By examining these numbers, we can deduce that MAGBO achieves the best results within 30 independent trials with a Rank (Friedman test) of 1. On a single-diode module, a double-diode module, and a PV module, MAGBO performs at a generally competitive level with the most recent robust algorithm.
Figure 14 displays the convergence curves of the MAGBO method and those of its competitors.
5.4. Tests MAGBO on a Wide Selection of Solar Cells and Modules
Data from the PVM 752 GaAs thin-film cell at 25 °C and total irradiation (1000 W/m
2) and the STP6-40/36 module are used to prove the validity and reliability of MAGBO, a method for detecting the properties of both the SDM and DDM of photovoltaic modules. The simulation parameters were determined using 44 pairs of I-V points from the PVM 752 cell [
85] and data from the STP6-40/36 module, which consisted of 36 series-connected polycrystalline cells and were tested at temperatures of 51 °C and 55 °C, along with measurements at varying temperatures and irradiance levels.
Table 6 details how we used actual data from STM6-40/36 and PVM 752 GaAs thin-film modules to determine the simulation experiment’s settings. The parameters of the compared algorithms are listed in
Table 3. Each issue runs using the same maximum number of iterations (600) across all methods.
5.4.1. Results Obtained Using the STM6-40/36 Simulation Model
In order to evaluate how well the proposed method compares to preexisting algorithms, we publish the results from the STM6-40/36 model [
86].
Figure 15 shows that the I-V and P-V curves generated by the simulation and the observations are highly consistent with one another. This supports the idea that MAGBO’s projections about the STM6-40/36 model’s characteristics are accurate. The STM6-40/36 model’s IAE and RE are also depicted in
Figure 16. The complete experimental results, including current, power, and corresponding IAR and RE values, are shown in
Table 14. It was found that IAE is less than 6.08803600
, which verifies that MAGBO’s determination of the STM6-40/36 model’s parameters is accurate.
Table 15 displays the best RMSE values for each of the seven approaches and the five most significant extracted parameter values based on a total of 30 tests.
Table 15 provides the RMSE values that are the most accurate, in addition to the five extracted parameter values that are the most significant, for each of the seven methods evaluated using a total of 30 tests.
Table 15 shows that MAGBO produces the best results with an RMSE value of 1.72981457
, the lowest possible value. Compared to other methods, the proposed MAGBO method is superior in terms of its performance when estimating the parameters of the STM6-40/36 model.
5.4.2. Results Obtained Using the PVM 752 GaAs Thin-Film Simulation Model
Using the SDM, we analyzed the suggested MAGBO technique to learn more about the characteristics of a PVM 752 GaAs thin-film cell.
Table 16 and
Table 17 detail the experiment outcomes, such as the current, power, IAE, and RE measured values.
Table 17 displays the simulated current data alongside the IAE and RE error measurements. The optimization method was found to be more challenging when applied to calculating the parameters of the PVM 752 thin-film cell than the RTC France solar cell.
Table 16 shows that despite this, the MAGBO approach is effective.
Table 17 displays the outcomes of different algorithms’ attempts to estimate the SDM parameters, and it can be observed that MAGBO fared best, with the lowest RMSE value.
Figure 17 shows the IAE and RE currents, both experimentally and as measured, for the PVM 752 thin-film cell model.
Figure 18 demonstrates that the I-V and P-V curves generated by the simulation and the measurements are highly consistent with one another, proving that MAGBO’s predictions for the PVM 752 thin-film model are correct.