Abstract: Because of increasing complexity in the power system, voltage sag is getting to be a standout amongst the most critical power quality issues. Voltage sag is a short decrease voltage from nominal voltage, happens in a brief timeframe. On the off chance that the voltage sags surpass a few cycles, and then manufacturing systems making utilization of delicate electronic types of equipments are prone to be influenced prompting real issues. It at last prompts wastage of assets (both material and human) and in addition money related misfortunes. This is conceivable just by guaranteeing that continuous stream of power is kept up at legitimate voltage levels. This project tends take a solution at the using so as to take care of the sag issues custom power gadgets, for example, Distribution Static compensator (D-STATCOM).Proposed plan takes after another calculation to create reference voltage for a distributed static compensator (DSTATCOM) working in voltage-control mode. The proposed plan guarantees that unity power factor (UPF) is accomplished at the heap terminal amid ostensible operation, which is unrealistic in the conventional technique. Likewise, the compensator infuses lower streams in this manner, diminishes misfortunes in the feeder and voltage-source inverter. Further, a sparing in the rating of DSTATCOM is accomplished which expands its ability to alleviate voltage sag. About UPF is kept up, while directing voltage at the heap terminal, amid burden change. The state-space model of DSTATCOM is joined with the miscreant prescient controller for quick load voltage regulation amid voltage unsettling influences. With these elements, this plan permits DSTATCOM to handle power-quality issues by giving power factor redress, consonant end, load adjusting, and voltage regulation in light of the heap necessity. The performance of the proposed system can be improved by adding Dynamic Voltage Restorer(DVR).
Keywords: DSTATCOM, Dynamic Voltage Restorer(DVR), Voltage Source Converter (VSC).