A new control method for Dynamic Voltage Restorer with asymmetrical inverter legs based on fuzzy logic controller

Dynamic Voltage Restorer (DVR) is used in power distribution system to protect sensitive loads in voltage disturbances. The performance of DVR is related to the adopted configuration and control strategy used for inverters. In this paper, an asymmetrical voltage-source inverter controlled with fuzzy logic method based on hysteresis controller, is used to improve operation of DVR to compensate voltage sag/swell. Simulation results using MATLAB/Simulink are presented to demonstrate the feasibility and the practicality of the proposed novel Dynamic Voltage Restorer topology. Total Harmonic Distortion (THD) is calculated. The simulation results of new DVR presented in this paper, are found quite satisfactory to eliminate voltage sag/swell.