ABSTRACT: The increasing demand for high-efficiency and power-quality improvement in AC-DC converters necessitates advanced techniques to minimize Total Harmonic Distortion (THD). This research focuses on the implementation of a Switching Capacitor Technique (SCT) to optimize the performance of a three-phase AC-DC converter by effectively reducing THD. The proposed method leverages controlled capacitor switching to shape the input current waveform, thereby improving power factor and reducing harmonic distortion without the need for complex active filtering. A comparative analysis with conventional PWM-based rectifiers and passive filtering techniques demonstrates the effectiveness of the SCT approach in achieving lower THD, higher efficiency, and improved voltage regulation. The system is designed and simulated in MATLAB/Simulink, and the results validate the significant reduction in harmonic content while maintaining stable output voltage. The findings suggest that the proposed technique can be a cost-effective and efficient solution for industrial applications requiring high power quality.