Fuzzy Hysteresis Controlled Active Harmonic Filter in Unbalanced Renewable Energy-Integrated Systems

Power quality and system stability are adversely affected by the harmonic distortion commonly introduced by the nonlinear behavior of renewable energy sources (RES) in grid-connected systems. Active Harmonic Filters (AHFs) are widely used to address these distortions, but traditional methods are less effective in unbalanced grid conditions. This paper introduces a novel AHF design employing Fuzzy Hysteresis Control that dynamically adapts harmonic mitigation in imbalanced renewable energy-integrated systems. A fuzzy-based hysteresis control strategy based on adapts to fluctuating load and harmonic conditions, ensuring reliable performance across various operational settings. Simulation and experimental results demonstrate the filter's ability to reduce harmonic distortion under typical grid scenarios. The proposed fuzzy hysteresis control method reduced harmonic distortion from 19.44% to 2.13% with traditional hysteresis control, and further optimization resulted in an impressive 0.34% reduction. These results excel traditional methods and bring harmonic levels within industry regulatory standards, significantly enhancing grid stability. The proposed control strategy offers an innovative power quality enhancement in renewable energy-integrated systems while creating more reliable and stable low-cost grid operations.