Analysis of Grid-Following and Grid-Forming Control Strategies for Grid-Connected Inverters in Weak Grid Conditions

This thesis presents a comprehensive study of the control techniques applied to grid-tied inverters, driven by their increasing deployment alongside the massive integration of renewable energy sources. The manuscript outlines a design methodology for the various control loops that make up grid-following and grid-forming architectures, specifically addressing both current source inverter and voltage source inverter implementations for the grid-forming approach. The core of this research focuses on assessing the stability limits and performance quality of these systems operating under weak grid conditions. This comparative analysis is supported by time-domain simulations and independently developed mathematical models that provide theoretical foundation for the observed phenomena. Finally, the thesis details an experimental setup designed to provide an initial hardware validation of the investigated control strategies.