Harmonic distortion is a significant issue in modern power systems, particularly for single-phase inverters used in motor drives, uninterruptible power supplies, and renewable energy integration. The non-linear switching of inverters introduces high-order harmonics that can shorten equipment lifespan, increase losses, and degrade power quality. This study focuses on designing and optimizing a passive RLC filter for harmonic mitigation in a MATLAB Simulink-modeled single-phase inverter system. A full-bridge inverter with sinusoidal pulse-width modulation (SPWM) was developed to assess distortion levels using Total Harmonic Distortion (THD). The unfiltered inverter output demonstrated a THD of about 25-30%, making it unsuitable for sensitive loads. With the optimized RLC filter, THD levels dropped below 5%, yielding a near-pure sinusoidal output and complying with IEEE-519 power quality standards. The results also showed that RLC filters enhance stability across various load impedances and improve efficiency to 96%, outperforming standard LC filters. Overall, this study presents a practical and cost-effective solution to enhance power quality in inverter-based renewable energy applications, while also paving the way for future experimental validation and hybrid filter development.
Keywords: Harmonic Distortion, Single-Phase Inverter, RLC Filter Design, Total Harmonic Distortion (THD), MATLAB Simulink Simulation
05-Sep-2026
