Comparative Performance Analysis of Order based Generalized Integrator type Phase Locked Loops for a polluted Grid

Properly synchronizing the grid connected Renewable Energy Sources (RES) in a three phase utility grid has become a significant consideration in recent times. The accurate alignment of the grid system voltage elements, including frequency, phase angle and amplitude is crucial for ensuring the effective synchronization of the grid interfaced inverter. While the synchronous reference frame phase locked loop (SRF-PLL) achieves this accurately during ideal grid scenario, it’s performance degrades during imbalanced and polluted grid conditions. To address this issue, there is a growing demand for highly effective and precise PLL structures like dual second order generalized integrator PLL (DSOGI-PLL), dual third order generalized integrator PLL (DTOGI-PLL) and dual mixed second and third order generalized integrator PLL (DMSTOGI-PLL) for the synchronization with grid. This study aims to investigate the three PLLs and compare their advantages and disadvantages in terms of adaptive filtering capability and the transient response. The objective is to identify a superior PLL with better performance under adverse grid conditions. The efficiency of these PLL systems has been evaluated through simulations using MATLAB/Simulink, considering abnormal grid scenarios. This research aims to find an effective grid synchronization method for integrating renewable energy into the power grid thereby improving overall stability, reliability and seamless integration.