Grid-connected PV system modelling based on grid-forming inverters

Abstract

This study investigates the design optimization and control strategies of grid-connected inverters, along with their interactions with the electrical grid. It establishes that the stability of grid-connected inverters is intricately linked to their performance, emphasizing that enhancements in overload capacity and protective mechanisms through hardware design are vital to ensure robustness. The thesis contends that inverters must demonstrate considerable robustness and adaptability to effectively manage varying grid and load conditions. To enhance response times and tracking capabilities, this thesis harnesses sophisticated control theories like Model Predictive Control (MPC), adaptive control, and fuzzy control. The design optimization process encompasses adjustments in circuit layout, thermal management, component selection, and the flexibility of control strategies. Furthermore, the study underscores the importance of inverters' capabilities for frequency regulation, phase synchronization, and voltage control in maintaining grid stability and operational efficiency. It also addresses the opportunities and challenges presented by high-capacity inverters in optimizing energy utilization, underscoring the necessity of judicious capacity selection to achieve a balance between efficiency, start-up latency, and component longevity. Ultimately, this thesis concludes that fine-tuning the design and control strategies for grid-connected inverters is paramount to heighten the utilization efficiency of renewable energy, fortify grid stability, and promote environmental sustainability.