Compatible Control of Power Sharing for Microgrid Systems Based on Inverters

This abstract presents a comprehensive strategy for controlling power sharing in parallel inverters within a single-phase AC microgrid. The strategy integrates continuous variable incline and discrete droop control with different gains to ensure stability. Additionally, proportional-resonant loops are incorporated to suppress harmonic components without impacting the dynamics of droop control. The microgrid system is modeled in a two-time-scale form, with droop control tracking real frequency variations in the slower time scale and power sharing dynamics, voltage regulation, and harmonic compensation operating in the faster one. Despite the presence of mismatches and uncertainties, the tracking error is shown to be asymptotically bounded, and the system remains input-to-state stable around the desired operation point. The relationship between control gain and power sharing performance index is analyzed throughout the experimental work, and a set of optimal gains is determined to ensure the fastest recovery of the power sharing error. It discusses a novel approach to flexible power-sharing control for inverter-based microgrid systems with fuzzification. Key features of the control strategy include advanced forecasting techniques for predicting generation and load patterns, real-time monitoring of system parameters, and the incorporation of a hierarchical control structure. To demonstrate the effectiveness of the proposed control approach, simulation studies were conducted on a representative inverter-based microgrid model with fuzzy logics demonstrating excellent dynamic performance in providing stable, fast, and accurate power sharing control.