Impact of battery storage on micro-grid transient performance

The increasing penetration of distributed generation (DG) into the electrical network presents new challenges to reliable operation of the system due to the special characteristics of DG units and their low inertia. This paper investigates the dynamic behavior of the system with multiple DGs. The main aim is to study the transient caused by the sudden integration of DG. The impact of the size of the storage device used is also considered in the paper. The simulation is carried out in DIgSILENT Power Factory 14.1 and a micro-grid setup in the laboratory is used for experimental validation. The results show that it is difficult for the micro-grid to maintain stability under a disturbance in islanding mode without any battery storage. The application of battery storage will considerably improve the micro-grid transient performance and the level of the DG integrated into the system is the critical factor that will determine the appropriate capacity of the battery.