A Droop Based Standalone Microgrid Control with Phase-Locked Loop (PLL) system

This research paper presents an advanced decentralized control approach for an independent AC microgrid with renewable energy-based distributed energy resources (DERs), including two solar PV-BESS systems. The DERs are connected to the microgrid through a three-phase voltage source inverter (VSI) network. The regulation of VSI voltage and frequency utilizes droop control, enhanced by integrating a phase-locked loop (PLL) system for inverter synchronization. The control approach ensures seamless power distribution and maintains voltage and frequency within specified limits across different operational scenarios. The control operations are based on the stationary frame (α−β) established via Clarke’s transformation. Proportional and resonant (PR) controllers are employed to regulate VSI voltage and current, ensuring performance and stability. The proposed control approach is validated through MATLAB/Simulink simulations, covering PV system behavior, load dynamics, and DER connection challenges.