Coordination control and energy management of standalone hybrid AC/DC microgrid

Abstract

An efficient energy management scheme for a standalone hybrid AC/DC microgrid (HMG) has been proposed in this paper. Energy management in a microgrid is a challenging task, because of the involvement of the distributed energy resources (DERs) which are intermittent in nature. The microgrid may therefore, undergo mismatch in demand and supply, when either the generation or load varies. This mismatch in power may result into DC bus voltage deviations and sometimes these deviations may be out of the permissible limits. A coordination control-based strategy (CCS) for DC bus voltage deviation mitigation and efficient energy management of the standalone microgrid is investigated here. The CCS is tested with the help of simulation studies on a test hybrid AC/DC microgrid in MATLAB covering all the scenarios which may arise. The test microgrid consists of a solar photovoltaic (PV) generation, a secondary source of generation, PEM fuel cell, a battery and a super capacitor. Coordination between the various sub-units and energy management of hybrid AC/DC microgrid is done using Fuzzy Logic Control (FLC) and the DC bus voltage deviations are also compared with PI based control system. It is found that the system with FLC has better performance than PI based control system.