Under Frequency Load Shedding in Inverter Based Microgrids by Using Droop Characteristic

In this article, a new Under Frequency Load Shedding (UFLS) method for Inverter-Based Microgrids (IBMs) is presented. The proposed strategy uses frequency variations to estimate the power deficit in IBMs without using wide communication platform and calculating system inertia time constant. Variations of power generation are considered during the load shedding process. The shortage of power is also compensated by the load shedding during several stages. Estimated droop coefficient is updated in each load shedding stage, enabling the proposed method to have a reliable performance in the case of the microgrid's parameters changes which could happen during the load shedding process. The proposed method is simulated and implemented in an IBM by using MATLAB\Simulink software package; the obtained results show the effectiveness and the correctness of the proposed scheme to recognize power deficit and to compensate power shortage.