## 4 Results and Discussion
### Full System Test  
The full system tests were conducted based on the configuration depicted in Figure 2. All the generalised parameters used in both simulation and experimental studies of the full system are presented in Table 6. Due to the usage of an actual PV panel in the test, it was difficult to specify any constant environmental conditions throughout any single test because the irradiance and temperature change over time. As a result, tests were carried out as long as the PV panel produced sufficient power to meet the load demand at a given irradiance and temperature. The boost converter stage was connected to the input V\({}_{2}\) of the inverter. The V\({}_{\text{ref}}\) selected for the POVC operation is presented in the same table. All values were selected to achieve the output peak voltage of 325.27 V, which corresponds to 230 V\({}_{\text{rms}}\). Figure 13 presents the experimentally generated switching signals. Figure 12: I–V and P–V curves of PV panel under the tested MPPT conditions. Efficiency analysis at RL = 258 \(\Omega\), 0.44 H.  
The operation of the system was tested under two types of loads, the purely resistive (R) load of 156 \(\Omega\) and resistive-inductive load (RL) of 168 \(\Omega\), 0.33 H. All measurements were made after the input V\({}_{2}\) achieved its required voltage level from the boost converter. Figure 14 shows the voltage and current waveforms produced by the inverter from both simulation and experiment. Under the R load, both the voltage and current waveforms were observed to be perfectly in phase with identical patterns. They differed only in amplitude. This is due to the fact that a purely resistive load has no filtering effect, and its linearity causes the current to duplicate the voltage waveform in accordance with [PERSON]'s law for every voltage step value and every voltage source combination. As a result, there was only active power present, which is entirely utilised by the load. The voltage and current waveforms were observed to be in phase with unity pf. Under the RL load, since the inductive component of the load acts as a low-pass RL filter, it could be seen that the current waveform was now smoothened and lagged the voltage waveform with the power factor pf of 0.86. The RL filter, in short, prevents high-frequency and allows low-frequency current signals to get through at the cut-off frequency, f\({}_{\text{cut}}\) which can be calculated using R/2\(\pi\)L. Any frequency greater than f\({}_{\text{cut}}\) was filtered, including high-frequency noise. For both \begin{table}
\begin{tabular}{c c} \hline \hline
**Parameters** & **Values** \\ \hline DC Power Supply V\({}_{1}\) (V\({}_{\text{DC}}\)) & 40.66 V \\ \hline POVC Reference Value for V\({}_{2}\) (V\({}_{\text{DC}}\)) & 40.66 V \\ \hline DC Power Supply V\({}_{3}\) (3V\({}_{\text{DC}}\)) & 121.98 V \\ \hline DC Power Supply V\({}_{4}\) (3V\({}_{\text{DC}}\)) & 121.98 V \\ \hline Output Voltage (Peak) & 325.28 V \\ \hline Output Voltage (RMS) & 230 V \\ \hline Output Frequency & 50 Hz \\ \hline Boost Converters Switching Frequency & 20 kHz \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Full system test parameters. Figure 13: Experimental switching signals. types of loads, the FFT analyses are given in Figure 15. Since the waveform shapes were identical, the output voltage and current under R load were found to have similar THD values of 3.87% from simulations. Experimentally, the voltage THD, THDv, and current THD, THDi values were also reasonably close. However, under the RL load, due to the inductive effect, the THDi has a reduced value of 0.38%, while the THDv still maintained an almost identical value of 3.88% as that obtained in the simulation. A similar case was also observed for the THDv measured experimentally. As for the experimental THDi, the value recorded by the power analyser meter was \(\sim\)1.8%.