Keeping the Power Clean: Harmonic Mitigation Strategies for High Solar PV Penetration in Distribution Networks

Abstract

The rapid growth of solar Photovoltaic (PV) integration in distribution networks is transforming modern power systems, but also raising significant concerns related to power quality. Among these challenges, harmonic distortion has emerged as a critical issue, caused by inverter-based generation and nonlinear interactions within the grid. Excessive harmonics can lead to equipment overheating, reduced efficiency, malfunctioning of sensitive devices, and overall grid instability. This study explores strategies for mitigating harmonics under high PV penetration, categorizing solutions into passive filters, active power filters (APFs), hybrid filter systems, and advanced smart inverter control. Additional engineering practices, such as load balancing, transformer phase-shifting, detuned capacitor banks, and network upgrades, are also reviewed. Furthermore, the importance of regulatory compliance with standards such as IEEE 519-2022 is emphasized to ensure uniform power quality across interconnected systems. By comparing these strategies in terms of cost, complexity, and effectiveness, the study highlights that a multi-layered approach, combining technological, regulatory, and engineering measures, offers the most effective pathway toward cleaner power and more resilient distribution networks in the era of renewable energy expansion.