Comparative Analysis of Passive, Active, and Hybrid Active Filters for Power Quality Improvement in Grid-Connected Photovoltaic System

The use of photovoltaic (PV) systems to generate electricity is expanding, making it more crucial than ever to ensure the quality of the power sent to the grid. In this paper, a grid-connected 50 kW PV system with load is considered. The comparative analysis of passive power filters (PPF), active power filters (APF), and hybrid active power filters (HAPF) for power quality improvement in grid-connected PV systems is demonstrated in this work. These filtering techniques aim to reduce Total Harmonic Distortion (THD) and improve the quality of power injected into the grid. PPFs, the simplest form of harmonic mitigation, employ passive components such as inductors and capacitors to attenuate specific harmonic frequencies. However, the performance of PPFs is limited, especially at low frequencies, and they may not be effective in reducing higher-order harmonics. APFs, on the other hand, offer greater flexibility and dynamic response compared to PPFs. However, a higher rating of active filter is considered a drawback of this filter. A HAPF has been proposed to combine the benefits of both active and passive filters. The HAPF offers better performance and a more affordable way to reduce harmonics for power quality improvement. The study is conducted through simulations in MATLAB/Simulink using a grid-connected PV system model. The performance of these filters is evaluated in terms of harmonic distortion reduction. The outcomes of this study will aid in determining the most effective type of filter to use while enhancing power quality in grid-connected PV systems.