Operation Analysis of an Islanded Microgrid with a Single Wind Power/BESS Generation Unit

Generation and load demand disparities that may occur during the islanding of a microgrid result in voltage and frequency fluctuations that cannot be mitigated by the generation if it is converter-interfaced to the loads. Existing literature describes strategies aimed at improving the ability of microgrids to regulate voltage and frequency, relying primarily on Battery Energy Storage Systems (BESS). These BESS systems can provide or absorb energy during imbalances, helping to reduce voltage and frequency fluctuations. When a hybrid unit is composed by PMSG-based wind turbine and BESS, the control system for the rectifier and boost converter connected to PMSG operates with Maximum Power Point Tracking (MPPT), while the bidirectional BESS converter controls power via power balance between wind generation and the microgrid's load; the Voltage Source Inverter (VSI) with droop control handles the grid interface with a grid-forming strategy in islanded mode. In this paper it analyzes the overall system performance, focusing mainly on the BESS drive system's ability to adapt power to unbalances between wind turbine and loads, thus encompassing test variations in wind speed and load. The simulations were performed in the MATLAB/Simulink environment, and the results indicate that this control approach effectively regulates the voltage and frequency levels.