ON SOME ASPECTS OF GRID SYNCHRONIZATION FOR SINGLE PHASE AND THREE PHASE SYSTEMS

Abstract

This thesis discusses the design, modeling and performance evaluation of various synchronization techniques. The techniques discussed in the thesis comprises phase locked loop (PLL) techniques applicable to single phase and three phase systems. Additionally, frequency locked loop (FLL) techniques applicable to single phase and three phase systems have also been studied and their performance has been compared. Moreover, experimental results have been obtained for a few single phase PLL techniques. Grid synchronization is a challenging task especially when the utility signal is polluted with disturbances such as harmonics or distorted frequency. Design, modeling and simulation of the complete system along with the controller have been carried out in MATLAB/SIMULINK environment. The focus of this thesis is to review these synchronizing techniques on the basis of frequency variations, voltage amplitude variations, phase angle variations and harmonics particularly for grid integration of renewable distributed power generating systems based on phase locked loop (PLL) and FLL.