Control Strategy of Hybrid AC/DC Microgrid in Standalone Mode

Abstract

The fluctuation of production of renewable energy resources (RESs) is a big problem for its installation and integration in isolated residential buildings. A hybrid AC/DC microgrid facilitates the good operation of RESs with a storage system in standalone mode and the possibilities of smart energy management. In this paper optimization research of the hybrid ac/dc microgrid in isolated mode of operation is presented. The power system is supplied by various Renewable Energy Resources (RESs), Photovoltaic arrays (PVA), a Wind Turbine Generator (WTG), Diesel Generator (DG) and supported by Batteries Storage System (BSS) for short term storage. The main objective of this study is to optimize power flow within a hybrid ac/dc microgrid with regards to reliability in islanded mode. First a mathematical model optimized by mixed integer linear programming and solved by CPLEX solver with JAVA language is developed for an islanded RES system and then, based on the developed model, the power system control is simulated for different cases of off-grid mode. Simulation results have shown that the management strategy can maintain power balancing while performing optimized control and give a controllable loads and batteries charging/discharging powers, even with unpredictability of RESs powers outputs and arbitrary energy tariffs. Finally, the proposed algorithm respects the optimization in real-time operation under various constraints.%.©2020. CBIORE-IJRED. All rights reserved

Study of power management of standalone DC microgrids with battery supercapacitor hybrid energy storage system

“…The supercapacitor has solved this issue due to having high power density [20], [23], [25]. The ratio of the total energy (Qc) to the rated energy (Q0) is called state of charge SOC% and it can be calculated as (15),…”

“…Controlling microgrids presents numerous challenges, as that they can operate both in isolated mode and connected to the 115 main network, through the point of common coupling (PCC) [11]- [14]. The system control must regulate frequency and voltage in any of the modes of operation, must distribute the load among the different distributed generations (DGs) and the storage, manage the flow with the network main and optimize operating costs [15]. The microgrid will switch to isolated mode in case of serious disturbances or failures and must then provide power to critical loads and the control system must in this case manage frequency and voltage [10]- [16].…”