A Novel Coordinated Control of Renewable Energy Sources and Energy Storage System in Islanded Microgrid

A novel coordinated control for energy storage system (ESS) and renewable energy source (RES) units is proposed in islanded AC microgrids without a phase-locked loop system. We use a proportional-resonant control technique for the ESS, which fixes the voltage and frequency of the microgrid. Moreover, we use a voltage-modulated direct power control (VM-DPC) technique, which has not only a good tracking performance but also a good steady-state behavior, for the RESs that generate their maximum power in the normal operation. To ensure the stability of the microgrid, we use the passivity property for RESs when the VM-DPC is sued. Hence, the whole system is still stable and passive after integrating the heterogeneous RESs into the microgrid. To validate the proposed coordinated control architecture, we use MATLAB/Simulink, SimPowerSystems to simulate a microgrid consisting of one ESS, one wind turbine, one photovoltaic and two controllable loads. Simulation results show that the islanded microgrid is operating well and the plug-and-play capability of the RESs is enhanced.