A Comprehensive Analysis of Three-Phase PLL-Based Grid Synchronization Methods

Grid synchronization is essential for maintaining efficient and reliable operation of power systems. Over the last few years, there has been a remarkable increase in the adoption of renewable energy sources and distributed sources to the grid. The large-scale renewable energy penetration and increase in the non-linear loads heightened the complexity of grid synchronization. In recent years, the Phase Lock Loop (PLL) based grid synchronization approaches gained significant attention in addressing these challenges. This paper is structured in two main sections. The first part provides a comprehensive analysis of various PLL-based algorithms. It delves into an in-depth analysis of various PLL methodologies, mathematical modelling, working principles, advantages, limitations, and their applications. The review scrutinizes classical PLLs, such as Synchronous Reference Frame PLL (SRF PLL), Double Second Order Generalized Integrator PLL (DSOGI PLL), Enhanced PLL (EPLL), Multiple Delayed Signal Cancellation PLL (MDSC PLL), Harmonic Inter Harmonic and DC Offset PLL (HIHDO PLL), Hybrid PLLs, etc. The review is also extended to advanced Digital Signal Processing (DSP) methods like Sliding Goertzal Discrete Fourier Transform PLL (SGDFT) and Sliding Fourier Transform PLL (SFT). Additionally, the recent developments in grid synchronization using the PLL-less approach are also discussed. The second section of the paper discusses the modeling of three-phase PLL using the Symmetrical Optimum (SO) method. It elaborates on the design of the model and its performance under various ideal and non-ideal cases.