Internal Model-Based Dynamic Power Control of Grid-Following Voltage-Source Inverters

This study proposes a robust control strategy to improve the stability and reliability of grid-following inverters with LCL filters, particularly under varying disturbances and instability conditions. A detailed survey of existing control strategies is presented to identify their limitations and highlight the advantages of Internal Model-Based Control (IMC). The analytical representation of IMC has been examined by demonstrating its inherent robustness against system uncertainties and external disturbances. The research focuses on a control method for grid-following inverters operating under challenging conditions such as grid disturbances, nonlinearities, and parameter variations. The effect of these factors on inverter performance is analyzed, and corresponding mitigation strategies such as advanced filtering and adaptive control mechanisms are discussed. A simulation framework is developed to assess the effectiveness of the proposed IMC-based control approach under various grid conditions. The results confirm that IMC enhances system stability, reduces harmonic distortion, and improves dynamic response. Moreover, the outcomes highlight the potential of IMC as a robust and adaptive control solution by providing valuable evaluations for advancing inverter technologies in weak grid environments and optimizing filter designs to achieve improved power quality.