Performance Analysis of Dual Third Order Generalized Integrator based Phase Locked Loop for Three Phase Distorted Grid Condition

The growing integration of Distributed power generation systems (DPGS) with the three phase power systems especially through power electronics-based voltage source converters (VSCs) is recently receiving considerable attention. To this end, a typical synchronous reference frame phase locked loop (SRF PLL) used for synchronization of the VSCs with the electric power network ensures in obtaining the amplitude, phase angle and frequency information same as the grid. The SRF PLL due to it's limited filtering ability is practically unsuitable for most of the applications. Dealing with this only SRF PLL's drawback, a large amount of advanced three phase PLLs have been suggested in the literature. Among them, Dual Third Order Generalized Integrator (DTOGI) PLL is an appropriate synchronization method for precise and quick determination of the utility voltage phase angle. In this paper, the DTOGI PLL is analysed and simulated in MATLAB/Simulink with respect to the most widely used Dual Second Order Generalized Integrator (DSOGI) PLL under various distorted grid conditions like sag with harmonics and variable frequency showing DTOGI PLL as an effective solution for synchronizing the interactive inverter of three phase grid with DPGS.