This article proposes designing and dissection of the distribution Static compensator (D-STATCOM) to mitigate power quality problem like voltage swelling and sagging that happens due to symmetric and asymmetric faults. The DSTATCOM system presents comparison between two models the first was designed for three phases together to measure voltage of three phases and the second dealing with the every phase to measure voltage of single phase separately. D-Stacom model is designed to study its effect in the case of symmetric three phase faults and asymmetric faults like single line to ground (SLG) fault, line to line (LL), and double line to ground (DLG). The control system is carried out utilizing the Pulse Width Modulation technique and PID controller to reduce voltage swelling and sagging. Ant Colony Optimization (ACO) was used to adjust mechanism of the PID controller. ACO was applied to find the optimum gain parameter of PID controller. The performance of D-STATCOM in mitigation voltage sags and swells are showed with the aid of MATLAB Simulink. Results of D-STATCOM showed excellent and effective performance in mitigation voltage sags and swells.