## 5 Experimental Data Analysis of the Isolated PVPS (Acquisition and Log)  
Figure 4 illustrates the data acquisition and calculation flow within the analytical framework of the PV-powered pumping system (PVPS). The PV generator power was estimated based on global irradiance and the average temperature of the photovoltaic cells, measured using a PV-calibrated reference cell. The DC bus voltage was monitored via a voltage transducer capable of detecting electrical shocks [35]. Motor electrical parameters, including active power and frequency, were acquired from the variable-frequency drive (VFD). Based on the electrical frequency of the motor, the start/stop events were counted [36]. The pump pressure was measured using a pressure transducer capable of detecting hydraulic shocks [37]. The pump flow rate was monitored with a flow meter to compute the cumulative pumped volume. The monitored, isolated, high-power, photovoltaic pumping system irrigated five sectors whose pressure reference was preset. In Table 2 are presented the nominal values (steady state) of the key parameters for each sector (operation points), obtained by analyzing the data collected during the monitoring campaign. Figure 4: Flow diagram of data acquisition and calculation within the analytical framework of the PVPS. From the entire monitoring campaign (the data collected every second during an entire irrigation campaign performed from March 2021 to November 2021), four representative days, each characterized by distinct cloud coverage conditions, were selected for detailed analysis:  
1. a clear day of sky, without any clouds;
2. a day where a big (large) and dense cloud passed slowly over the PV generator during the day;
3. a day with multiple small clouds that passed quickly and sequentially over the PV generator;
4. a fully cloudy day. These days were selected not for their frequency but for the distinct operational conditions they represent in terms of system demand. Figures 5-12 use a consistent color scheme to represent data from the four distinct days, each characterized by different sky conditions. Measurements from the clear-sky day are shown in blue, those from the day with a big (large) and dense cloud in green, those from the day with multiple small and fast-moving clouds in red, and those from the fully cloudy day in purple. Theoretical values are plotted in black and shocks (shown on the right axis, where appropriate) are highlighted in yellow. Figure 5 illustrates the global irradiance \(G_{PV}\) of the photovoltaic generator [W/m\({}^{2}\)] during the five types of representative days, calculated using Equation (1) based on the short circuit current \(I_{CPVSc}\) measured with the calibrated photovoltaic cell [A]:  
\[G_{PV}=\frac{I_{CPVSc}\cdot G_{PVPtc}}{I_{PVPcstc}} \tag{1}\]  
where \(G_{PVPtSc}\) represents the photovoltaic panel irradiance at standard conditions [1000 W/m\({}^{2}\)] and \(I_{PVPcstc}\) represents the photovoltaic panel short circuit current measured under standard conditions [9.45 A]. Analyzing Figure 5, it is evident that all four representative days occurred within a similar seasonal period, characterized by sunrise slightly after 06:00 and sunset shortly before 18:00. The recorded peak global irradiance was 937 W/m\({}^{2}\) for the clear-sky day (Figure 5a), 1058 W/m\({}^{2}\) on the day partially obstructed by a large cloud (Figure 5b), 1022 W/m\({}^{2}\) on the day with frequent small clouds (Figure 5c) and 1014 W/m\({}^{2}\) on the fully cloudy day (Figure 5d).