Application of Dynamic Voltage Restorer in microgrid for voltage sag/swell mitigation

Microgrids are becoming increasingly attractive to consumers as it allows utilization of freely available renewable energy sources. They are usually installed at consumer´s sites i.e the distribution end. Due to high penetration of distributed generation units with different types of loads, microgrids can cause power quality and power control issues. Some of them are voltage swells and sags, and low power factor which further require reactive power compensation. This paper presents the utilization of the custom power device specifically Dynamic Voltage Restorer (DVR) in mitigating the problem of voltage sags and swells occurring in microgrid. A microgrid is modeled and simulated with different loading conditions causing power quality problems. The performance of DVR, installed in microgrid, is analyzed for reactive power compensation to overcome these concerned issues. The control logic of DVR is designed using phase locked loop (PLL) technique and its effectiveness is observed in Matlab/Simulink.