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2025

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  1. School of Electrical Engineering, Chuzhou University, Chuzhou 239000, Anhui, China. playjoy@163.com
  2. Cardiology Department II, The First People’s Hospital of ChuZhou, Chuzhou 239000, Anhui, China



Partial shading, Photovoltaic array, MPPT, GA-GWO-INC hybrid algorithm

1. Introduction

1.1. Motivation

The global energy sector is confronted with a lot of challenges, including an increase in the demand for electricity, the necessity to reduce carbon emissions, and the need to take Sustainable Development into account [1, 2]. Consequently, many countries are turning to the use of clean energy sources, including solar PV power. According to the International Renewable Energy Agency, the share of electricity generated from Renewable Energy Sources (RES) worldwide will be 90% of the total by 2050 [3, 4]. Solar energy is the main reason behind these predictions. Despite the rapid growth in the implementation of solar PV power designs, solar PV's efficiency drops due to environmental factors like partial shading of solar panels that create various Maximum Power Points (MPP) besides the Global MPP (GMPP) [5, 6]. The problem gets aggravated as a result of rapidly varying solar irradiances. In such conditions, classic MPPT techniques, including the Perturb and Observe (P&O) technique and the INC Method, face difficulties in distinguishing MPPs from the GMPP [7, 8].

To overcome these issues, intelligent optimization algorithms like metaheuristics have been used to boost the efficacy of the MPPT system. Swarm intelligence algorithms like Particle Swarm Optimization (PSO) [9, 10], Whale Optimization Algorithm (WOA), and GWO [11, 12], have been found promising as far as improving the tracking error and the execution speed with lesser complexity. The above algorithms perform well under complex environmental scenarios where traditional algorithms are not able to find optimal solutions. Although there are many strengths in algorithms like adaptive moment estimation and stochastic gradient descent that apply to this scenario, some limitations exist in achieving a balance between tracking accuracy and implementation ability under dynamic shading scenarios [13, 14].

The study regarding the hybridization of MPPT techniques that benefit from the strengths of different optimizing methods has gained extensive attention [15, 16]. In this regard, some studies in which GA is hybridized with the GWO and INC methods have demonstrated encouraging results in improving the accuracy of global searches as well as localized optima to boost the reliability of an MPPT system. The hybrid approaches demonstrated potential to handle changes in environmental dynamics and exhibited superior tracking abilities under partially shaded conditions. However, there are still challenges in its convergence speed and stability in environmental dynamics that represent a significant R&D field [17, 18].

1.2. Literature review

The reason for the growing demand for the adoption of photovoltaic (PV) systems is the need for more sustainable energy sources [19]. There remain challenges in tracing GMPP in the presence of partial shading. Variations in the incidence of solar energy can cause the presence of harmonics in the system. Moreover, connecting a PV system to a power grid increases concerns associated with Total Harmonic Distortion (THD) in the system. The need for addressing all these concerns and identifying innovative ways for efficient monitoring of GMPP and enhanced performance of a PV system has been stressed in a study conducted by Sharma and Mishra [20]. The study focused on various AI-based MPPT techniques and their features and limitations. It has even reasoned upon techniques for lessening THD in a PV system and recommended Adaptive Filters (AF) as a successful technique for eliminating noise and interference. The review article has brought out fresh aspects of identifying superior AI-based MPPT techniques for making optimizations in PV systems.

Due to the need for optimized MPPT techniques, Bhukya and Shanmugasundaram recommended a study on the performance analysis of a solar-based PV system through a conventional MPPT technique in [21]. The researchers evaluated the current-voltage curve and power-voltage curve for a solar-based PV system. The researchers applied a Perturb and Observe technique to validate MPPT in a different environmental setting. The study concluded that a theoretical comparison of MPPT techniques is required to validate the applicability of a Perturb and Observe MPPT technique in a real-time setting for a solar-based PV system. Et-Torabi et al. in [22] recommended a comparison between ANN and a Perturb and Observe MPPT technique in a solar-based PV system that consisted of a solar-based PV generator and a boost DC-DC converter with a resistive load. The research mainly studied the difference of MPPT methods in a solar-powered system under unchanging and changing environmental conditions. To verify the results of MATLAB Simulink modeled MPPTs, a real-world setup with LAUNCHPAD-XL 28F379D and a C2000 embedded coder was used. It has been found by the researchers that an ANN-based MPPT technique yields more power in a stable environment as well as in a varying one. The ANN-based MPPT method can easily accommodate a change in situation, and simultaneously, it is capable of producing a steady power output.

Moving on to the future of MPPT, Gopalakrishnan et al. introduced a new idea to enhance the performance of PSO based MPPT in the PV systems, which are partially shaded [23]. The authors embraced the foundational principle of a meticulous study of bird flocking behavior for their invention. The research finding was that in bird flocking behavior, the individual birds initially fly in random patterns, but ultimately they turn to the central point. Hence, there was a creation of a modified PSO method that allows particles to continue their random search in the solution space for a longer time, but finally, they come to a global optimal point. The recommended technique significantly improved the MPPT locus-tracking capabilities of a flock and can therefore be applied to improve MPPT in partially shaded PV systems. Both calculated and experimental MPPT curves were given to validate this technique.

Zhou and Zhang in [24] developed a high-precision engineering mathematical (HPEM) model for a PV array to overcome limitations in traditional mathematical models that are unable to simulate some MPPs accurately in a shading situation. The HPEM mathematical model, developed for a single-diode model with a compensation coefficient ($\beta$), ranging between 0.5 and 1.2, is a substantial improvement over traditional methods where a fixed value of $\beta = 0.5$ is considered. The model is more efficient and more accurate for MPPT. To represent multiple peaks in a PV output curve, the scientists created a piecewise mathematical model grounded on series-parallel circuit theory for shaded areas. According to the HPEM simulation, the model gets very close to zero-error MPPT MPP and power values when temperature and irradiation vary from 25◦C to 80◦C and 200-1000 W/m2, respectively, with the relative errors being 0.08% and 0.07%. It is very close to traditional MPPT in that it accurately predicts multimodal distributions with less than 1% extremum localization error and thus overcomes the common problem of local trapping. These theoretical concepts and models constitute a milestone framework for comprehending complex photovoltaic behavior under extreme lighting and the design of large-scale array configurations.

To address the multi-peak characteristics of the P-V curve under partial-shading scenarios, Hao Wu et al. in [13] developed a new MPPT control tactic combining a chaos-based grey wolf optimizer (CGWO) and a variable step INC (VINC) algorithm. The CGWO optimizes traditional random numbers in GWO to improve diversification capabilities in searching for better positions. The incorporation of VINC within this novel strategy increases MPPT accuracy. Comparisons between this strategy and traditional MPPT approaches like INC-GWO, Cuckoo Search (CS), PSO, and Perturb & Observe (P&O) revealed better performance. The efficiency and accuracy were improved in this strategy as it minimized average computation time for convergence by 53.30% and boosted accuracy by 1.37% in comparison to traditional strategies. The strategy optimized total solar utilization steadily and efficiently in a PV system when operated under different partial-shading scenarios.

In conclusion, an optimized MPPT control strategy has recently been recommended by Bian et al. [25] to overcome a deficiency that traditional MPPT control strategies have in failing to track the global MPPT when a partial shading scenario exists. The optimized strategy relies on an improved bacterial foraging algorithm (BFA), in which a leader approach is added to promote improvements in chemotaxis. In addition to this, a similar triangle assignment strategy has also been recommended to improve the elimination-dispersal process according to the optimal individual. The parameters of the optimization model, including its initial location and restart strategy, have been designed according to its characteristics in relation to generating a maximum power output in a photovoltaic array. The simulation and real-world experiments have proved that this optimized BFA-based MPPT strategy performs well in rapidly identifying and locating the global MPPT while simultaneously greatly improving the efficiency of a photovoltaic array.

Despite the promising performance of existing hybrid MPPT strategies, several limitations remain. Most GA-GWO or GWO-INC methods rely on fixed parameter settings, which limits their adaptability under rapidly changing environmental conditions. In addition, many approaches adopt a loosely coupled or sequential structure, where global and local optimization stages operate independently, resulting in insufficient interaction and suboptimal performance. Furthermore, the lack of a clear coordination mechanism between exploration and exploitation may lead to premature convergence or oscillatory behavior near the MPP. These limitations motivate the development of a more tightly integrated and adaptive hybrid optimization framework.

1.3. Research Gap and Contribution

To address the limitations of existing hybrid MPPT methods, this paper proposes a GA-GWO-INC cooperative optimization framework with tightly coupled global-local interaction and dynamic parameter adaptation. Compared with existing GA-GWO, GWO-INC, and other hybrid strategies, the main contributions of this work are summarized as follows:

(1) Dynamic parameter adaptation mechanism: A time-varying crossover probability and mutation factor are introduced, enabling the algorithm to maintain strong exploration ability in early stages while ensuring convergence stability in later stages.

(2) Embedded GA-GWO interaction mechanism: Unlike conventional cascade structures, GA operators (crossover and mutation) are directly embedded into each GWO iteration, forming a deeply coupled population evolution process, which effectively prevents premature convergence.

(3) Two-stage coordinated optimization framework: A structured global-local optimization strategy is developed, where the GA-GWO hybrid performs global exploration, and the INC method is adaptively activated for monotonic local refinement near the MPP, improving tracking accuracy.

(4) Mechanism-level convergence synergy: The proposed method integrates the contractive convergence of GWO, the diversity enhancement of GA, and the monotonic adjustment property of INC into a unified optimization framework.

These features distinguish the proposed method from existing hybrid MPPT approaches and provide a more robust solution under dynamic partial shading conditions.

2. Mathematical Scheme of the Photovoltaic (PV) System

Fig. 1 displays the equivalent mathematical scheme of the PV cell and provides its output characteristic equation [26], displayed as Eq. (1). Explanations of the parameters are given in Table 1.

(1)
$I_L = I_{ph} - I_D - I_{sh} = I_{ph} - I_o \left[ \exp\left( \frac{q(U_{oc} + I_L R_S)}{A K T} \right) - 1 \right] - \frac{U_{oc} + I_L R_S}{R_{sh}}.$

Fig. 1. Equivalent circuit diagram of the PV cell.

../../Resources/ieie/IEIESPC.2026.15.5.741/fig1.png

Table 1. Description of PV cell parameters.

Symbol Definition
$K$ Boltzmann constant, valued at $1.38 \times 10^{-23}$ J/K
$I_{ph}$, $I_D$ Photogenerated current, reverse saturation current
$U_{OC}$, $I_L$ Solar cell output voltage, solar cell output current
$q$, $A$, $T$ Electric charge, PN-junction factor, PV cell temperature
$R_S$, $R_{Sh}$, $I_{sh}$ Equivalent series resistance, equivalent shunt resistance, and equivalent parallel current of the cell

A PV array is constructed by connecting multiple PV cells in series or parallel. Fig. 2 presents the MATLAB/Simulink scheme of the PV array, while Table 2 details the parameters of the PV cells.

Fig. 2. Simulation scheme of the PV array.

../../Resources/ieie/IEIESPC.2026.15.5.741/fig2.png

Table 2. Photovoltaic (PV) panel parameters.

Symbol Definition Reference value
$G_R$ Maximum irradiation under standard conditions 1000.00 W/m2
$T_R$ Temperature under standard conditions 25.00◦C
$U_{oc}$ Open-circuit voltage at standard conditions 36.30 V
$I_{sc}$ Short-circuit current at standard conditions 7.84 A
$V_{mpp}$ MPP voltage at standard conditions 29.00 V
$I_{mpp}$ MPP is current at standard conditions 7.35 A

Table 3 presents three different irradiance conditions and the corresponding MPP values derived from Fig. 3.

Table 3. Irradiance configurations and MPP values for three different operating conditions.

Scenario $S_1$/(W/m2) $S_2$/(W/m2) $S_3$/(W/m2) MPP value/W
I 1000 1000 1000 8518.24
II 1000 500 1000 6791.11
III 1000 500 500 5062.97

Fig. 3. Power-voltage (P-V) characteristic curve.

../../Resources/ieie/IEIESPC.2026.15.5.741/fig3.png

3. Design of the GA-GWO-INC Hybrid Algorithm

3.1. Application of GA in MPPT Optima

In MPPT for PV systems, GA employs three fundamental genetic operations: selection-replication, crossover, and mutation to optimize the population fitness. This approach facilitates the swift identification of the MPP while effectively mitigating the challenges associated with local optima.

3.1.1 Selection and replication

In a population $S$ of size $N$, chromosome $X_i \in S$ is selected to reproduce according to its probability of selection $P(X_i)$. In total, within $N$ iterations, $N$ chromosomes are selected at random to reproduce from $S$. The equation for $P(X_i)$ is given as

(2)
$P(X_i) = \frac{f(X_i)}{\sum_{j=1}^{N} f(X_j)}.$

3.1.2 Crossover

Crossover combines beneficial properties from each of the parental chromosomes to generate a new child chromosome. The whole procedure is controlled by a crossover probability as defined in Eq. (3), below:

(3)
$p_c(t) = p_{c,\max} - \frac{(p_{c,\max} - p_{c,\min})}{T_{\max}} \times t.$

In Eq. (3), $p_c(t)$ and $p_{c,\max}$ are denoted as the initial and maximum crossover probability, respectively. The variables $t$ and $T_{\max}$ symbolize the current cycle and the maximum count of cycles.

3.1.3 Mutation

Mutation brings new genetic information to improve the diversification of the population and therefore avoids a local optimum. The variable for dynamic mutation is given below:

(4)
$F(t) = F_{\min} + \frac{(F_{\max} - F_{\min})}{T_{\max}} \times t.$

In Eq. (4), $F_{\min}$ represents the lower dynamic factor, and $F_{\max}$ represents the upper dynamic factor.

3.2. Application of the Grey Wolf Optimizer (GWO) in MPPT

In MPPT for a PV system using GWO, a leadership hierarchy is created among four kinds of GWs: alpha ($\alpha$), beta ($\beta$), delta ($\delta$), and omega ($\omega$). The alpha has generally better fitness and is known as the leader of the group. The level of fitness for a beta is second to that of the alpha and is considered to aid in some decisions made in conjunction with the alpha. The fitness level for a delta is third and is known to support alpha and beta. The rest of its group is known as omega and follows alpha, beta, and delta when they are out for a hunt.

3.2.1 Searching for prey

The process in which the grey wolves find their prey involves first diverging depending on the location of the alpha, beta, and delta wolves and then reassembling to launch a joint attack on their target. Mathematically describing this deviation to their strategy in finding prey, in the GWO algorithm, a random variable named ‘A’ is used with $|A| > 1$. The role of ‘C,’ a random value in between 0 and 2, is vital. The value of ‘C’ is a random weight given to the location of ‘prey.’ If ‘C’ is greater than 1, its impact increases. Conversely, if ‘C’ is less than 1, its impact is reduced.

3.2.2 Encircling the prey

The following equations are introduced to mathematically describe how grey wolves (GWs) encircle their prey during hunting:

(5)
$D = |C X_p(t) - X(t)|,$
(6)
$X(t + 1) = X_p(t) - A D.$

In Eqs. (5) and (6), $t$ displays the current cycle index, $D$ displays the distance vector between a wolf and its prey, $X_p(t)$ is the prey’s movement vector, $X$ is the wolf’s movement vector, $A$ and $C$ signify cooperation vectors given by

(7)
$A = 2 a r_1 - a,$
(8)
$C = 2 r_2.$

In Eq. (7), $r_1$ and $r_2$ signify random vectors in [0,1], and $a$ implies the convergence factor that declines linearly from 0.5 to 0 as cycles proceed.

3.2.3 Attacking the prey

GWs can locate prey and carry out encirclement, with the alpha wolf typically leading the hunt while the beta and delta wolves may also participate. Treating the alpha wolf as the desired resolution and the beta and delta wolves as the second and third-best solutions, the pack’s positions are updated according to the expressions below:

(9)
$\begin{cases} D_\alpha = |C_1 X_\alpha - X|, \\ D_\beta = |C_2 X_\beta - X|, \\ D_\delta = |C_3 X_\delta - X|, \end{cases}$
(10)
$\begin{cases} X_1 = |X_\alpha - A_1(D_\alpha)|, \\ X_2 = |X_\beta - A_2(D_\beta)|, \\ X_3 = |X_\delta - A_3(D_\delta)|, \end{cases}$
(11)
$X(t+1) = \frac{X_1 + X_2 + X_3}{3}.$

In Eqs. (9), (10), and (11), $D_\alpha$, $D_\beta$, and $D_\delta$ are the distance vectors from the prey to the alpha, beta, and delta wolves, respectively. $C_1$, $C_2$, and $C_3$ signify constant vectors; $X_\alpha$, $X_\beta$, and $X_\delta$ display the position vectors of the alpha, beta, and delta wolves; and $A_1$, $A_2$, and $A_3$ are coefficient vectors.

3.3. The Application of INC in MPPT

In the MPPT of photovoltaic systems, the INC method determines the operating point more precisely by calculating the incremental relationship between power and voltage in real time. This power-voltage incremental relationship is derived using Eq. (12).

(12)
$\frac{\Delta P}{\Delta U} = \frac{P_{new} - P_{old}}{U_{new} - U_{old}}.$

In Eq. (12), $P_{new}$ is the power value after the position update, $P_{old}$ is the power value before the update, $U_{new}$ is the voltage after the update, and $U_{old}$ is the voltage before the update.

Next, by substituting Eq. (12) into Eq. (13), we obtain the updated duty cycle.

(13)
$D(t + 1) = D(t) + k \times \text{sign}\left(\frac{\Delta P}{\Delta U}\right).$

In Eq. (13), $D(t + 1)$ is the duty cycle after the update, $D(t)$ is the duty cycle before the update, $k$ is the step size for adjusting the duty cycle, $\text{sign}\left(\frac{\Delta P}{\Delta U}\right)$ denotes the sign function.

3.4. Design of the GA-GWO-INC Hybrid Algorithm for MPPT

In this work, the proposed GA-GWO-INC algorithm is not a simple sequential hybridization, but a deeply integrated cooperative optimization framework. Specifically, GA-based crossover and mutation operators are embedded within each GWO iteration, enabling continuous population diversification during the global search process. This design allows the algorithm to dynamically balance exploration and exploitation, rather than relying on fixed-stage switching. Specifically, after the fitness evaluation and leader ($\alpha, \beta, \delta$) updating in each GWO iteration, GA-based crossover and mutation are applied to the candidate positions to generate a diversified population for the next GWO update. The dynamic mutation factor (see Eq. (4)) helps adjust the search strategy, making it more exploratory at the beginning of the cycles, while Eq. (3) gradually weakens the crossover operation in later stages to enhance convergence stability. By substituting Eqs. (4) and (3) into Eqs. (7) and (9), we get

(14)
$A^* = 2 \times F(t) \times r_1 - F(t),$
(15)
$\begin{cases} D_\alpha^* = |P_c(t) X_\alpha - X|, \\ D_\beta^* = |P_c(t) X_\beta - X|, \\ D_\delta^* = |P_c(t) X_\delta - X|. \end{cases}$

By substituting Eqs. (14) and (15) into Eq. (10), the new vector values of $X_1^*$, $X_2^*$, and $X_3^*$ (as displayed in Eq. (16)) are obtained. From these, an update strategy (Eq. (17)) is derived that effectively integrates the advantages of multiple solutions. Eq. (17) is expressed as follows:

(16)
$\begin{cases} X_1^* = |X_\alpha - A_1^*(D_\alpha^*)|, \\ X_2^* = |X_\beta - A_2^*(D_\beta^*)|, \\ X_3^* = |X_\delta - A_3^*(D_\delta^*)|, \end{cases}$
(17)
$X_c = \begin{cases} \frac{X_1^* + X_2^* + X_3^*}{3}, & r < X_c, \\ \frac{X_1^* + X_2^*}{2}, & r > X_c. \end{cases}$

In Eqs. (16) and (17), $r$ is a random number, and $X_c$ is the updated position vector.

To strengthen the theoretical rigor of the proposed hybrid GA-GWO-INC algorithm, an explanation of its convergence characteristics is provided as follows. In the GWO component, the convergence factor $\alpha$ decreases linearly from its initial value to zero, causing the coefficient vector $A = 2\alpha r - \alpha$ to satisfy $|A| < 1$ in later iterations. This ensures that the position update of each wolf becomes a contractive mapping toward the leader positions, forming the theoretical basis for global convergence.

In addition, the genetic crossover mechanism integrated into the position update employs a bounded and gradually decreasing crossover probability. This design provides stronger exploration during the early iterations while reducing the perturbation effect in the later stage, ensuring that the genetic operator remains stable and does not disrupt the contractive behavior of the GWO search. Furthermore, the INC refinement step monotonically adjusts the duty cycle based on the sign of $\Delta P/\Delta U$. Convergence occurs when $\Delta P/\Delta U = 0$, corresponding exactly to the MPP condition. Therefore, the INC stage operates as a monotonic local refinement mechanism capable of correcting small deviations that may arise during global search.

By combining the contractive global search of GWO, the bounded and decreasing perturbation of the genetic operator, and the monotonic refinement of the INC adjustment, the overall iterative update satisfies $\|X(t + 1) - X(t)\| \to 0$. This indicates that the hybrid method converges toward a stable region around the global MPP. The simulation results in Tables 6 and 7 further confirm this conclusion by demonstrating fast convergence, strong tracking accuracy, and reliable performance under both static and dynamic partial shading conditions.

From a computational perspective, the proposed GA-GWO-INC algorithm maintains relatively low complexity because it employs a small population size and a limited number of iterations in the global search stage. The computational complexity of the GWO-based search is approximately $O(NT)$, where $N$ represents the population size and $T$ denotes the number of iterations. In this study, $N = 10$ and $T = 5$, resulting in a very small computational burden. After global exploration, the INC method performs lightweight local refinement with minimal arithmetic operations. Therefore, the overall computational load remains suitable for real-time implementation in embedded photovoltaic controllers.

In addition, the proposed algorithm does not require large-scale matrix operations, deep neural network inference, or high-dimensional optimization calculations. Most computations involve basic arithmetic operations and iterative position updates, which can be efficiently executed on commonly used DSP, MCU, or FPGA-based photovoltaic control platforms. Due to the small iteration count and low memory occupancy, the proposed method demonstrates favorable real-time implementation potential for practical photovoltaic energy conversion systems under dynamic partial shading conditions.

4. MATLAB Simulation Analysis

The recommended GA-GWO-INC algorithm in this exploration has made use of the strengths and advantages of all three methods in making a stable, quick, and accurate MPP tracker for a PV system. The step-by-step procedure for how this recommended GA-GWO-INC algorithm works is as follows:

(1) Firstly, initialize the positions of a group of wolves. Define parameters for cycles in an algorithm and constants. Subsequently, define fitness for an individual.

(2) Arrange all individuals according to their fitness. Then, update all positions related to alpha, beta, and delta.

(3) GA algorithm execution. Update $F(t)$ based on Eq. (4), and then update all position vectors for all wolves based on Eq. (17).

(4) The algorithm approaches nearer to the value of the global optima, which is an MPP, through cycles.

(5) The final step is to apply INC in Eqs. (13) and (14) to control the duty cycle to track MPP.

As described in the above procedure for the cited hybrid algorithm, simulations are conducted in MATLAB/Simulink for a $5 \times 8$ array of series-connected PV cells. The output circuit structure for this array is given in Fig. 4.

Fig. 4. Output circuit topology of the photovoltaic array.

../../Resources/ieie/IEIESPC.2026.15.5.741/fig4.png

The GA-GWO-INC hybrid algorithm presented in this article uses the strengths and advantages of each method, thereby enabling the fast, stable, and precise tracking of a PV system’s MPP. To clearly report the optimizer settings and improve reproducibility, Table 4 summarizes all parameters used in the proposed GA-GWO-INC algorithm. These values correspond directly to the MATLAB implementation used in the simulations. The pseudocode for this paper is shown in Algorithm 1.

Table 4. Parameters used in the GA-GWO-INC hybrid optimizer.

Parameter category Parameter name Value/Range Description
GWO parameters Population size 10 wolves Corresponds to 10 initial duty-cycle candidates uniformly distributed in [0, 0.7].
Convergence factor $\alpha$ Linearly decreases from $0.5 \to 0$ within 5 iterations Ensures contractive behavior in the GWO update.
GA Parameters Dynamic crossover probability $0.8 - 0.1 \cdot t$, where $t =$ iteration index High exploration in early cycles, reduced perturbation in later cycles.
Mutation factor range Determined by Eq. (4), bounded within the defined upper and lower limits Provides controlled diversity without destabilizing GWO.
INC Parameters Step-size $k$ 0.0005 Fine-grained local refinement near the MPP.
Stability/Smoothing Damping factor 0.05 Smooths the duty-cycle update to avoid sudden changes.
Dynamic environment handling Irradiance-change threshold 0.02 of the previous power Triggers reset under rapid shading variation.
Duty ratio constraints Bounds $0 \le D \le 0.95$ Prevents invalid or unstable converter operation.

Algorithm 1. Pseudo-code of the algorithm

../../Resources/ieie/IEIESPC.2026.15.5.741/al1.png

4.1. Power Tracking Test Under Static Shading

The comparison between INC, GWO, GWO-INC, and GA-GWO-INC approaches under partial shading (PS) is done through simulation. The corresponding graphs for the output power waveform under static shading are given in Figs. 5-7.

Fig. 5. Output power waveforms for scenario I. (a) INC. (b) GWO. (c) GWO-INC. (d) GA-GWO-INC.

../../Resources/ieie/IEIESPC.2026.15.5.741/fig5.png

Fig. 6. Output power waveforms for scenario II. (a) INC. (b) GWO. (c) GWO-INC. (d) GA-GWO-INC.

../../Resources/ieie/IEIESPC.2026.15.5.741/fig6.png

Fig. 7. Output power waveforms for scenario III. (a) INC. (b) GWO. (c) GWO-INC. (d) GA-GWO-INC.

../../Resources/ieie/IEIESPC.2026.15.5.741/fig7.png

The convergence time is defined as the time instant when the tracked power first reaches and remains at or above 95% ($\ge 95\%$) of the final steady-state maximum power. The corresponding values for time and accuracy are displayed below in Table 5.

Table 5. Tracking time and accuracy results for different algorithms under static shading conditions.

Scenario Algorithm Power (W) Accuracy (%) Convergence (s)
I INC * * 0.025
GWO 8506.60 99.857 0.101
GWO-INC 8517.60 99.992 0.104
GA-GWO-INC 8517.82 99.995 0.092
II INC * * 0.015
GWO 6771.16 99.706 0.099
GWO-INC 6790.07 99.985 0.083
GA-GWO-INC 6790.36 99.989 0.055
III INC ** ** ***
GWO 4761.02 94.036 0.100
GWO-INC 5062.62 99.993 0.110
GA-GWO-INC 5062.88 99.998 0.104

Note: * indicates large power oscillation, ** indicates being trapped in a local optimum, and *** indicates no measurable convergence time.

As shown in Table 5, in tracing accuracy, GA-GWO-INC has always demonstrated a superior accuracy above 99.989% for Scenarios II and III. In comparison to the INC, GWO, and GWO-INC algorithms, there exist possibilities of stability problems and even occurrences of entrapment in a local optimum. As for convergence time, GA-GWO-INC has not only demonstrated superior accuracy but has also optimized tracing time. In tracing times for Scenarios I and II in comparison to other methods, GA-GWO-INC has reduced tracing times between 9.4% and 34%, thus significantly improving system response times.

4.2. Power Tracking under Dynamic Shading

The simulation is done for validating power tracking in a scenario that has a time-varying lighting condition. The process operates in Scenario I for $t=0$ to 0.5 seconds. Later, for $t=0.5$ to 1 second, it operates in Scenario II. Furthermore, for $t=1$ to 1.5 seconds, it operates in Scenario III. The output power of all four algorithms is displayed in Fig. 8.

Fig. 8. Power output waveforms under dynamic shading. (a) INC. (b) GWO. (c) GWO-INC. (d) GA-GWO-INC.

../../Resources/ieie/IEIESPC.2026.15.5.741/fig8.png

The settling time is defined as the time required for the tracked power to reach and remain at or above 95% ($\ge 95\%$) of its final steady-state peak value. The table below shows a summary of experimental track time and accuracy for all algorithms.

Table 6. Tracking time and accuracy results under dynamic shading.

Scenario Algorithm Power (W) Accuracy (%) Convergence (s)
I INC * * 0.030
GWO 8506.58 99.863 0.101
GWO-INC 8517.58 99.992 0.105
GA-GWO-INC 8517.80 99.995 0.099
II INC * * 0.015
GWO 6788.87 99.967 0.144
GWO-INC 6790.10 99.985 0.171
GA-GWO-INC 6790.35 99.989 0.094
III INC ** ** ***
GWO 5055.58 99.854 0.159
GWO-INC 5062.20 99.985 0.153
GA-GWO-INC 5062.87 99.998 0.118

Note: * represents drastic fluctuation of power, ** represents getting trapped in a local optimum, and *** represents no measurable convergent time.

As Table 6 reveals, the GA-GWO-INC hybrid algorithm achieves the highest accuracy under all test conditions. Here, particularly in Scenario III, it achieves 99.998%, which is much higher compared to GWO (99.854%) and GWO-INC (99.985%). Contrarily, the INC algorithm indicates extremely high accuracy oscillations and gets trapped in a local optimum in Condition III, and indicates extremely low precision.

As far as time tracing is concerned, GA-GWO-INC provides superior accuracy and involves considerable time savings. In Scenario II, for instance, tracing time is reduced by about 45% compared to GWO-INC, demonstrating excellent responsiveness. Meanwhile, the proposed method maintains tracking accuracy above 99.989% under all tested conditions, indicating a favorable balance between steady-state precision and transient response performance.

4.3. Discussion

A PV system has huge potential and has immense promise to meet the growing energy demand and address some environmental issues to a large extent. However, there remain some concerns about effectively implementing it in a situation where partial shading is involved. The presence of more than one point in the power-voltage curve in a scenario where partial shading is involved makes it a very challenging task for the traditional MPPT technique to track the Global MPP. In this exploration, a fresh GA-GWO-INC MPPT tactic has been recommended to address this challenging scenario. The recommended technique is a combination of GA, GWO, and INC methods.

The recommended method is a combination of GA crossover and mutation methods and optimized methods in GWO, and has additional exploitation capabilities in the vicinity through INC. The adaptive cross probability and step size in INC are added to this optimized method to ensure that this optimized method has better search capability and exploitation in the vicinity. The recommended optimized method has been developed in a simulation scheme for a PV system for different scenarios to analyze its better performance in comparison to traditional methods like INC, GWO, and GWO-INC.

The results mentioned earlier have clearly proved that for GA-GWO-INC, there is a huge improvement regarding other techniques in MPPT for MPP. In all scenarios that were considered for testing, GA-GWO-INC has maintained its accuracy to 99.998%, wherein there is a decrease of 45% in convergence time. In all scenarios that contain dynamic shades, GA-GWO-INC has proved its better capability and ability to resist and track the global MPP without entrapment in a local optimum. The above results indicate that GA-GWO-INC can assist in boosting the efficiency of a PV system even in a complex scenario. From a practical application perspective, the proposed method not only improves tracking accuracy, but also reduces transient power loss during rapid irradiance variation. In practical photovoltaic systems, environmental conditions such as moving clouds and partial shading frequently cause operating-point deviations. Faster convergence enables the PV array to return more quickly to the global maximum power point, thereby improving dynamic energy capture capability. In addition, the proposed method maintains tracking accuracy above 99.989% under all tested shading conditions while reducing convergence time by up to 45%, demonstrating favorable real-time performance for photovoltaic MPPT applications.

Although it has some promising results, some limitations are associated with this work. Firstly, it can easily be concluded that this algorithm is still heavily dependent on variables like probability and step size. But in the near future, this issue can easily be resolved in more in-depth works related to either optimizing this existing algorithm or using adaptive techniques. The scalability of this hybrid technique for large-scale scenarios in relation to PV and complex shading patterns may provide some valuable information. In a nutshell, it can easily be concluded that even though this recommended technique has brought iconic development in accuracy and efficiency in solar path-tracking techniques, its computational complexity remains moderate and suitable for real-time implementation. Moreover, because the proposed algorithm only requires a small population size, limited iteration cycles, and simple arithmetic operations during the local refinement stage, it can be implemented on practical embedded photovoltaic controllers with relatively low processor and memory requirements. This characteristic further improves its engineering applicability for real-time MPPT control under dynamic partial shading environments. But its development in relation to stability and efficiency in partial-shading patterns for a photovoltaic system has supreme significance in solar technology advancement.

5. Conclusion

The reason for carrying out this research work is to develop a novel GA-GWO-INC MPPT technique that will handle partial shading and peak power/voltage points. The novel GA-GWO-INC MPPT technique is a combination of a GA, GWO, and INC for better accuracy and reliability. Compared with conventional hybrid MPPT methods, the proposed approach introduces a dynamic and tightly coupled optimization mechanism, which fundamentally enhances both convergence reliability and tracking accuracy.

In addition to that, GA's capability for global search, GWO's optimization capability, and INC's adaptive step size are all incorporated. The above-mentioned recommended algorithm is explained in detail below. The recommended algorithm is evaluated for its efficiency in different scenarios of shading in a simulation process. The recommended scheme is programmed in MATLAB.

The key mathematical and analytical results are:

• The GA-GWO-INC produced a tracking accuracy of 99.998% in comparison to other traditional methods.

• The time required to reach a state of convergence has reduced by 9.4% to 34% to become more responsive to changes in shading.

• The recommended algorithm demonstrated improvement in dynamic shading environments with a high level of accuracy and a lower chance of reaching local optima.

• The partial shading condition helped in achieving a stable power output for GA-GWO-INC that improved efficiency and reliability in relation to the PV system.

In this scenario, it has been observed that the recommended GA-GWO-INC algorithm is highly effective for MPPT in a PV system, especially in a complex partial shading scenario. In this context, future works can focus on optimizing parameters to apply this algorithm in a real-time system and verifying its scalability for a large-scale scenario in a PV system. Moreover, in a real-world scenario for a PV system, more concrete results can be derived related to this recommended algorithm.

Acknowledgments

This exploration is backed by the Program for Science and Technology Innovative Research Team of Chuzhou University and the Open Project of the State Key Laboratory of Luminescence and Applications (SKLA-2023-20) and the Innovative Talent Training Project for Electrical Engineering and Automation under the "6 Excellence & 1 Top Talent" Program (2023zybj041) and the Anhui Province University Natural Science Research Key Project 2025AHGXZK30280.

Competing of Interests

The authors declare no competing of interests.

Authorship Contribution Statement

Jin Peng: Writing-Original draft preparation, Conceptualization, Supervision, Project administration.

Yang Zhou: Methodology, Software, Validation.

Yangyi Zhang: Formal analysis, Language review.

Data Availability

On Request

Declarations

Not applicable

Conflicts of Interest

The authors declare that there is no conflict of interest regarding the publication of this paper.

Author Statement

The manuscript has been read and approved by all the authors, the requirements for authorship, as stated earlier in this document, have been met, and each author believes that the manuscript represents honest work.

Ethical Approval

All authors have been personally and actively involved in substantial work leading to the paper, and will take public responsibility for its content.

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Jin Peng
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Jin Peng was born in Anhui province, AH, China in 1981. He received the B.S. degree in electronic information from the Northeastern University, China, in 2003 and the M.S. degree in electronic information from the Northeastern University, China, in 2007. Since 2007, he has been an associate professor with the Department of Electrical Engineering, Chuzhou University, Anhui province. His research interests include Electronic and electrical engineering, more than 10 papers published and 2 book published.

Yang Zhou
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Yang Zhou was born in Anhui province, AH, China in 1981. She received the B.M. degree in clinical medicine from Anhui Medical University in 2004 and the M.M. degree in clinical medicine from Nanjing University in 2014. Since 2004, she has been a chief physician in the Department of Cardiology, the First People’s Hospital of Chuzhou, Anhui province. Her research interests include ECG signal processing, more than 4 papers published.

Yangyi Zhang
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Yangyi Zhang was born in Anhui province, AH, China in 1983. He received the Ph.D. degree in electronic science and technology from Nanjing University, Jiangsu, China, in 2021. Since 2025, he has been an professor with the Department of Electrical Engineering, Chuzhou University, Anhui, China. His research interests include microelectronics and semiconductor materials.