Citation :

Rampalli Jagan, Bhaskar Kanna, "Fuzzy MPPT Enabled PV Integration to Grid Through a GFL Asymmetrical 31-Level Inverter Without an LC Filter," International Journal of Electrical and Electronics Engineering, vol. 13, no. 5, pp. 161-172, 2026. Crossref, https://doi.org/10.14445/23488379/IJEEE-V13I5P113

Abstract

Integration of renewable sources into the grid is a critical task, as the renewable sources generate power mostly in DC. The grid to which it is connected is a three-phase AC grid, where the renewable source needs to be synchronized to the grid voltage magnitude and frequency. In order to achieve this, a GFL asymmetrical 31-level inverter is employed. The inverter is connected to multiple Fuzzy MPPT-based PV units with asymmetrical voltage levels for the generation of multi-level voltages. Each phase comprises four PV units, which generate voltage levels at Vdc, 2Vdc, 4Vdc, and 8Vdc. The Fuzzy MPPT-enabled PV-integrated asymmetrical 31-level three-phase inverter is connected to the grid without an LC filter. This reduces the power losses and the cost of the converter, as a high-rated LC filter module needs to be integrated. The inverter needs a feedback signal for synchronizing with the grid, which is generated by the GFL controller. A simulation analysis is carried out on the proposed PV-grid connected system, presenting all the parameters of the system. The THD of the PCC voltages and inverter currents is maintained as per the IEEE standards (below 5%) even without the LC filter. The power loss is ensured to be maintained at a low level, increasing the efficiency of the system. The complete analysis is done by using the MATLAB Simulink tool with graphs of the measured parameters plotted with time as reference.

Keywords

GFL (Grid Following), MPPT (Maximum Power Point Tracking), PV (Photo Voltaic), THD (Total Harmonic Distortion), PCC (Point of Common Coupling), MATLAB.

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