The proliferation of nonlinear loads in modern power systems has introduced significant power quality challenges. Among these loads, rectifiers commonly used in various applications are notable for generating harmonics and causing power disturbances. To address these issues, this chapter presents a novel design of a three-phase, three-wire shunt active power filter (SAPF) aimed at mitigating harmonic distortions and improving power quality. The proposed SAPF operates in parallel with the nonlinear loads and employs the synchronous reference frame (SRF) technique for reference current calculation. Pulse width modulation (PWM) is utilized to control the voltage source inverter (VSI), ensuring precise harmonic compensation. The performance of the SAPF is evaluated through MATLAB simulations, which demonstrate a significant reduction in total harmonic distortion (THD) from 27.99 to 4.65%. The results underscore the effectiveness of the SAPF design in enhancing power quality and mitigating harmonic disturbances caused by rectifiers.