Voltage sag/swell compensation using Z-source inverter DVR based on FUZZY controller

The power quality requirement is one of the major issues for power companies and their customers. The analysis of power disturbance characteristics and finding solution to the power quality problems have resulted in an increased interest for power quality. The most concerning disturbances affecting the quality of the power in the distribution system are voltage sag/swell. The DVR is used to mitigate the voltage sag/swell on sensitive load. In this paper Z-source inverter (ZSI) based DVR is proposed to enhance the voltage restoration property of the system. The ZSI uses an LC impedance grid to couple power source to inverter circuit and prepares the possibility of voltage buck and boost by short circuiting the inverter legs. Additionally a fuzzy logic control scheme for Z-source inverter based DVR is proposed to obtain desired injecting voltage. Modelling and simulation of the proposed DVR is implemented in MATLAB/SIMULINK platform.