A New Load Frequency Control Strategy for an AC Micro-grid: PSO-based Fuzzy Logic Controlling Approach

Lack of sufficient synchronous generators (SG) and high integration of renewable energy sources (RES) raise several challenges in micro-grid (MG) operation, especially in terms of system stability. In fact, MG suffers from low-inertia condition which results in high risk of frequency instability following disturbances. Therefore, it is mandatory to compensate the lack of sufficient frequency control ancillary services (FCAS) by alternative solutions. This paper presents an optimal Fuzzy-logic based secondary frequency control in order to improve MG frequency stability through management of system active power. The proposed Fuzzy-logic controller benefits from robustness and simplicity in order to ameliorate frequency deviations. To improve the efficiency of the method, Fuzzy membership function parameters are optimized based on a multi-objective function using Particle Swarm Optimization (PSO) algorithm. Finally, the proposed strategy is assessed in various scenarios.