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.
Fig. 1. Equivalent circuit diagram of the PV cell.
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.
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.
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
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:
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:
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:
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
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:
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).
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.
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
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:
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.
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
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.
Fig. 6. Output power waveforms for scenario II. (a) INC. (b) GWO. (c) GWO-INC. (d)
GA-GWO-INC.
Fig. 7. Output power waveforms for scenario III. (a) INC. (b) GWO. (c) GWO-INC. (d)
GA-GWO-INC.
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
|
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.
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
|
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.