It comprises a photovoltaic generator (PV) that supplies power to a solar pumping system, driven by a

permanent magnet direct current motor (PMDC) via a DC-DC Buck converter. Consequently, the objective is

to maintain steady operation with continuous power supply despite changes in two environmental parameters,

including solar irradiation and absolute temperature. The maximal power extraction of the PV panel using the

usual perturbation and observation (P&O) technique achieves this objective. This method must provide

appropriate duty cycle control for the DC-DC buck converter when the user-selected Fixed-Step Size (FSS) is

used, unfortunately, selecting an insufficient fixed-step size led to a power ripple issue with the PV panel.

Incorporating a new Variable Step-Size (VSS) into the traditional P&O algorithm shows the occurrence of the

enhanced P&O-MPPT control approach. The proposed technique is validated by utilizing the PROTEUS/ISIS

software. For various climatic situations, the results demonstrate that the proposed control technique is

As Algeria is a developing nation, water supply and

accessibility in various locations are hampered by

the presence of numerous rural areas and variable

weather conditions. In such situations, a solar water

pumping system is an excellent alternative for

build, [2].

environmentally clean, unlike hydrocarbon fuels

(oil, gas, and coal), making them the focus of social

and industrial sectors, [3]. Solar photovoltaics, one

of the renewable energies, are abundant on the

planet's surface, simple to convert to direct power,

adaptable, and do not require sophisticated

mechanical parts that create noise during

production, [4], [5]. To increase the performance of

among which the P&O control is the most prevalent.

However, its effectiveness is modest, and its

oscillations around the MPP are significant, [8].

the investigation of water pumping from the primary

hand pump to high-efficiency electric pumps with

less effort and energy. Diesel pumping is

extensively investigated in remote locations without

access to the electrical grid. However, this technique

demands an expensive and environmentally

mounting structure, [12] .

designed to harvest the most power feasible from

the PV module can reduce the total system cost,

[13], [14]. Numerous approaches for MPPTs have

been consistently developed and enhanced. These

techniques include perturb and observe (P&O) [15] ,

incremental conductance [16], hill climbing [17],

[18], fractional open-circuit voltage, fractional

short-circuit current, neural network, fuzzy logic

fixed step size) is routinely employed in PV field

applications, [7], [23], [24] because of its ease of

implementation. The latter is determined by

perturbing the PV output voltage and watching the

output voltage on the PV array's power, [25], [26].

Multiple sensors are required for measuring the PV

current and voltage. In addition to failing the peak

power test, [27], [28], it exhibits instability in the

steady-state regime, making it less precise and

potentially causing energy loss when there are

frequent and rapid variations in light. A small step

size may be selected to prevent oscillations, even

though this decision leads to a lengthy response

time, [29]. Therefore, when selecting the increment,

between the reference and actual torque speed when

these techniques are supported by speed control.

Our work aims to describe the design characteristics

system using Proteus/Isis software. Additionally,

this paper proposes a modified P&O MPPT

algorithm to address the shortcomings of the

standard P&O method when operating under

varying weather conditions, thereby significantly

improving the accuracy of the control system.

Figure 1 depicts the connection layout of the

analyzed system. The modified water pumping

system includes a DC-DC buck converter fed by a

PV source, an MPPT-controlled PMDC motor, and

Fig. 1: Simplified diagram of the global system

The permanent magnet DC motor (PMDC motor)

has been modeled in terms of both torque and rotor

angle, [32], [33]. The PMDC motor model is

developed using Proteus/ISIS software, as illustrated

in Figure 2. The characteristic equations of a PMDC

load and electromagnetic torques, respectively. The

model, however, is constructed using Equations (1),

(2), and (3). Additionally, the PMDC motor block

can be consolidated into a single block through

simulation with the Proteus/Isis software.

Where Ipv, Iph, Ish, Id, and Isd denote the currents

of: output, PV panel, shunt resistor, diode, and

environmental inputs have been examined. Figure

(5a) illustrates the Ppv (Vpv) curves for solar

radiation ranging from 500 to 800 W/m² at a

constant 25°C. Figure (5b) depicts the Ppv (Vpv)

curves for temperatures ranging from 20 to 40°C

and constant solar radiation of 1 kW/m².

Fig. 5: Ppv (VPV) curves of the simulated module

A PV array is designed by connecting 4 PV

modules in series and 2 modules in parallel.

been included in the proposed study because it has

corresponding connection points on the adapter for

increased lift, [39]. The duty cycle for the Buck

converter is set at 100% conversion, a feature not

achievable when using the boost converter.

Fig. 6: DC-DC Buck Converter

The bidirectional converter runs in Buck mode

With u1 = 1 if Q1 is closed and 0 otherwise.

PV systems are recognized for their low efficiency

and nonlinear nature, [40]. Additionally, PVs have a

unique maximum power point (MPP). Due to the

has a basic structure and is easy to implement;

hence, it is recognized among the most popular

MPPT algorithms. Its central concept is based on

the zero dP/dV values at the peak of the power-

voltage curve. The P&O operates by perturbing

(decreasing or increasing) the current or voltage of

the PV array based on a comparison between the

actual output power P(n) and that of the preceding

perturbation P(n-1). Figure 7 depicts the

recommended algorithmic flowchart for tracking the

can be used to find the system reference speed that

corresponds to output power maximization.

This section will discuss the proposed supervision

scheme for the solar pumping system. Any silicon

device, such as a CPU or digital signal processor,

can monitor the PV panel depicted in Proteus

software, [46]. The combination of Arduino MEGA

and ISIS Proteus software creates a compatible and

effective photovoltaic pumping system. Figure 8

demonstrates that this system is also feasible in

with fixed and variable step sizes).

The Arduino board is used to calculate the

proper duty cycle, which is then sent to the

MOSFET of the buck converter for control. In

addition, the LCD screen is utilized to display

Fig. 8: Arduino-based control unit structure

with manual switching is modified.

board transmits the PWM (duty cycle) control signal

to the Buck converter (simulated in Proteus).

Additionally, the LCD panel will display the

measurements (voltage, current, power, and duty

cycle (%)). Moreover, all technical data will be

transmitted to the Proteus software for real-time

curve display.

A comparison of two MPPT techniques is

conducted to validate the suggested method. In a

photovoltaic pumping system, these strategies have

been implemented. The latter does not require an

the steady state more quickly, but the oscillations

therein are substantially higher. It takes 0.05 s to

reach the MPP. However, the 0.005 step P&O takes

1 s to reach the MPP. A more significant step can

further improve the P&O algorithm's dynamic

performance. Despite this, static performance will

suffer as a result. A P&O method with varying steps

can prevent or mitigate these performance

deficiencies (in both dynamic and steady-state

regimes). Our method has eradicated the steady-

maximum power reference (1.5174 kW, 0.9336 kW,

and 0.7387 kW).

Fig. 11: Comparison of PV output power (Proposed

VSS-P&O and FSS P&O)

The simulations were conducted under constant

temperature (25°C) and illumination (800 W/m²).

Additionally, distinct perturb steps (δω) have been

When the step size is increased, the FSS P&O

P&O are superior to those of competing techniques.

Table 3. Comparison between P&O fixed &

variable step-size techniques

Moreover, it achieves a significant efficiency of

99.60% and a tiny relative error in all examined

circumstances. On the other hand, steady-state

power oscillations are large, with a relative

inaccuracy reaching 3.86 percent when using the

classical method.

temperature and incident solar energy, vary

throughout the day. These variations differ

significantly based on the examined zone.

PV system's power. As depicted in Figure 12, the

value of solar irradiation decreases in the intervals

[0 sec, 6 sec] and [8 sec, 10 sec], and increases in

sensitivity. During periods of transitional irradiance,

the PV system's power closely follows the MPP.

irradiation.

In this instance, a sudden temperature change from

20°C to 40°C is applied. Figure 13 depicts the

temperature-dependent simulation findings. In this

simulation, a constant solar radiation parameter of

0.8 kW/m² has been employed. The switching

frequency of buck converters is inversely related to

temperature. Additionally, when this value drops,

the motor's rotational speed increases. In contrast, as

evident that the latter offers a dynamic performance

that is relatively adequate; it can swiftly converge to

the steady-state regime, albeit with more significant

oscillations. The two examples above demonstrate

that our methodology is more advantageous to the

water pumping system than the conventional

method. These scenarios replicate the natural

findings demonstrate that our method can identify

the optimal performance for each environmental

change by modifying the MPP search. Additionally,

by using speed-based P&O, the performance in

terms of rotor speed stability is significantly

enhanced, mainly due to the elimination of voltage

modeling flaws. Table 4 outlines the primary

characteristics of the various MPPT algorithms.

These algorithms were assessed and compared

based on their technical knowledge of PV panel