Frequency Regulation and optimization of Microgrid System with Multi PV-VSG using Advanced Droop Controller

The future of the machine-controlled power system is advancing to an inverter-based power system with a huge integration of renewable energy sources (RES) like photovoltaic (PV) and wind energy. The penetration of RES leads to instability of frequency due to the lack of inertia. Recent development has been made in inverter’s based virtual inertia control for frequency regulation in virtual synchronous generator-based systems. Inverters connecting to the microgrid are provided with virtual inertia and droop control by the virtual synchronous generator (VSG) system. In this study, three parallel VSGs based PV systems are used to investigate the frequency response and voltage stability. An advanced genetic algorithm (GA) optimization method is utilized to attain the optimum parameters of the droop control used in the VSGs. Furthermore, two different case studies with respect to load change are analyzed in detail with comparisons with the classical droop controller. The simulation results observed many improvements of the proposed controller over the classical controller.