An overview of various grid synchronization techniques for single-phase grid integration of renewable distributed power generation systems

Due to the increasing penetration of single-phase distributed generations into the utility grid the need of an improved and efficient controller to control the distributed power generating systems (DGs) is also increasing. Therefore the grid synchronization techniques plays a major role in order to maintain the grid requirements in terms of power quality and the frequency of the grid voltage. The informations of grid voltage frequency, amplitude and the phase are the basic requirements for single-phase grid integration. For efficient estimation of these, various synchronization techniques have been proposed. The focus of this paper is to review the different synchronization techniques particularly for grid integration of single-phase renewable DGs based on Phase Locked Loops (PLL) and Non-PLL method.