A Novel Steepest Descent Least Mean Square Control for Smooth Mode Transfer of a Single-Stage SPVA-BES Hybrid Microgrid

This study introduces a single-stage, three-phase hybrid microgrid (MG) that effectively utilizes distributed energy resources (DERs), including battery energy storage (BES) and solar photovoltaic array (SPVA). A novel filtering method, the steepest descent least mean square (NSDLMS) technique based on Al-Alaoui digital differentiator, is implemented. This technique is integral to voltage source converter (VSC), ensuring rapid convergence and clean grid current outputs. In instances of polluted grid conditions, a dual-modified generalized integrator (DMGI) is employed as a pre-filter to mitigate issues and maintain power quality. This system demonstrates seamless transition capabilities between grid-connected mode (GCM) and standalone mode (SAM). The proposed system architecture, featuring a robust VSC control and pre-filter, aims to deliver continuous and dependable power to local nonlinear loads amid various challenges such as fluctuating solar exposure, imbalanced and polluted grid conditions, grid failures, and realignment procedures. Operational results in both GCM and SAM indicate that VSC fulfils a multi-objective role by ensuring uninterrupted power to the load with a unity power factor (UPF) and total harmonic distortions (THDs) within the 5% limit accepted by the IEEE 519 and 1547 Standards. The efficacy and effectiveness of proposed NSDLMS filtering technique and DMGI pre-filter are rigorously tested on a MATLAB platform and further substantiated through a hardware prototype developed and examined in a laboratory setting.