Fuzzy adaptive selfish herd optimization based optimal sliding mode controller for frequency stability enhancement of a microgrid

Abstract

In recent power system, the quality of power is highly influenced by the imbalance between generation and load demand. Automatic Generation Control (AGC) is an imperative control strategy to minimize the frequency or power deviation by regulating the generation. In this work, a centralized Sliding Mode Control (SMC) is employed as AGC to achieve reliable performance of a Microgrid (MG). Due to existence of some poor inertia sources in MG, a knowledgeable and reliable controller is very indispensable. Wind turbine, photovoltaic unit, fuel cell, aqua-electrolyser, fly-wheel, ultra capacitor, battery energy storage units reside in MG with nonlinearities such as Generation Rate Constraint (GRC), communication delay and anomalous load. Further, a Small Hydro Power Plant (SHPP) is integrated with MG to enhance the performance response. The performance of the controller is enhanced by Selfish Herd Optimization (SHO) and a novel fuzzy adaptive SHO (FASHO). The decisive parameters of SHO are decided by fuzzy logic control by which the efficacy of algorithm is improved. The proposed FASHO based SMC controller is substantiated over SHO/FASHO based PID, FOPID and FOPID-(1 + PI) controllers. The proposed FASHO-SMC controller and integration of SHPP are wrapped up as superior approaches to enhance the performance of MG.

Keywords

• Fuzzy adaptive Selfish Herd Optimization
• Microgrid
• Sliding mode control
• Small hydro power plant
• Fractional order PID controller