A solution for frequency control in islanded three-phase micro-grids supplied by Renewable Energy Sources

This paper studies the frequency control in an islanded micro-grid (MG) supplied by Renewable Energy Sources (RES). The MG contains two generators, a synchronous generator, an induction one, and loads. Frequency stabilization is obtained by using a hybrid solution with a dump load (DL) and an energy storage system (ESS) based on a battery bank. The generators available power and the loads demand gives the power unbalance, which lead to frequency deviation. To reestablish the initial power balance a power sharing algorithm it is used between DL and ESS. The system dynamic behavior is studied, under variable load and variable generated power. Also, the ESS battery state of charge is taken into account. Simulation of the system using Matlab/Simulink software was performed to illustrate the advantages and limitations of this control strategy.