FPGA-Based Fuzzy Logic Controllers Applied to the MPPT of PV Panels—A Systematic Review

Maximum power point tracking (MPPT) is a technique for continuously extracting the largest amount of energy that a source can provide under varying conditions, and it is indispensable for modern photovoltaic (PV) panels. Among several methods to achieve this, fuzzy logic controllers (FLCs) have been a popular choice over the years, incorporating human-like thinking into their design to promote flexibility, robustness, and reliability. In addition, due to its high performance, low power consumption, and high circuit density, a field-programmable gate array (FPGA) may be a suitable choice for implementing these controllers. This study aims to identify the applicability of FPGA-based FLCs for the MPPT of PV panels. A systematic literature review was conducted, focusing on five research questions. The methods proposed in the 14 selected studies were analyzed in terms of their advantages and limitations. Results demonstrate that FLCs are remarkably adequate for MPPT, although they are preferred when used in conjunction with other techniques. By employing FPGAs, fuzzy controllers may achieve significantly faster responses at an overall lower cost. However, this comes with increased complexity and resource usage. The findings highlight the suitability while acknowledging the limitations of FLCs and FPGAs for the MPPT in PV panels. Moreover, some aspects still require further research, such as methods for dealing with partial shading conditions, the analysis of modern techniques not yet explored in FPGAs, and the integration of FPGA-based technologies in large-scale grids.

I. Introduction

In An era of ever-increasing interest toward sustainable energies, efficient photovoltaic (PV) panels are indispensable to properly benefit from solar power. However, these panels inherently have low efficiency, making it crucial to maximize the energy extracted from them. Moreover, environmental conditions, such as irradiance and temperature, significantly influence the maximum power that a PV module can provide at any given moment. To circumvent that, a general approach is to have a controller constantly tracking the maximum power point (MPP) and driving the system to it—this method is typically called maximum power point tracking (MPPT) [1], [2]. Studies in recent years seem to be focusing on further increasing MPPT-based systems' efficiency by integrating multilevel inverters (MLIs) and shunt active power filters (SAPFs) to reduce total harmonic distortion (THD) [3], [4], [5].