A Unity Power Factor Rectifier based Dynamic Voltage Restorer for Microgrid Applications

With lesser dependence on fossil fuel, the greener energy policies are focusing on renewable energy sources. Numerous such sources together form the distributed energy resources for micro-grid. Micro-grids can operate in islanding and grid connected mode. Thus, critical loads face higher vulnerability for harmonic disturbances. Dynamic voltage restorers (DVR) are commonly used to protect critical loads by curtailing adverse effects of voltage fluctuations. Energy storageless DVRs tap in power from the transmission line through rectifier. However, rectifiers pose challenge of injecting current harmonics and higher THDs into the system, which will have further adverse effect on the critical loads. Therefore, this paper focuses on the operation of unity power factor rectifier topology for DVR. The use of unity power factor rectifier is analyzed for taping in power from the line so as to maintain the power quality. The analysis is carried out in MATLAB/Simulink and the simulation results are presented.