Voltage Sag/Swell and Harmonics Compensation for Sensitive Loads: A Dynamic Voltage Restorer Approach with PI-Fuzzy Controller

The growth in the use of power electronics has caused a greater awareness of power quality. Voltage sags/swells, and harmonics can cause equipment to fail, shut down, as well as create huge current imbalances that could blow fuses or trip breakers. These consequences, which might range from small quality variances to production halts and equipment damage, can be quite costly for the consumer. In this paper, a PI-fuzzy logic controlled DVR to mitigate the voltage sag, voltage swell, and harmonics in different loads and conditions is presented. PI-fuzzy Controller gave a better performance with THD generated only 0.90% while with PI controller 1.74% THD is generated. Also, the magnitudes of both voltage sag and voltage swell are restored back to the nominal value. The results are compared with the conventional PI controller and simulated offline using MATLABT/Simulink software.