Hybrid Energy Storage For Microgrid Performance Improvement Under unbalanced load Conditions

Energy storage system (ESS) is generally used to manage the intermittency of the renewable energy sources (RESs). One of the important issues in microgrids is to supply high quality powers to consumers. This paper proposes the use of hybrid energy storages to improve the power quality under unbalanced load conditions for microgrids applications. Battery and SC are used as hybrid energy storages systems (HESSs) that provide low and high power frequency respectively. The proportional resonance(PR) and fuzzy controllers are, respectively, used to regulate the AC load voltage and DC bus voltage controller. The main advantages of the proposed energy management scheme are to reduce battery power fluctuations, better DC bus voltage regulation for generation and load disturbances, improvement system performance under unbalanced load conditions, reduced rate of charge/discharge of battery current, improved power quality feature under unbalanced load and transition conditions. The performance of the proposed method and control strategy is verified by using simulation studies in the MATLAB software environment.