Hybrid Energy Storage System in Standalone DC Microgrid with Ramp Rate Limitation for Extending the Lifespan of Battery

The one problem in standalone microgrid with photovoltaic (PV) and wind energy systems is the fluctuation of power output. The battery energy storage system (BESS) is used to improve reliable operation of microgrid by managing the power output. However, the intermittent power charge/discharge of BESS is the one factor that harmful effect to its lifespan. In recent years, the hybrid energy storage system (HESS) with BESS and supercapacitor (SC) has been proposed for increase performance of the system and extend BESS's lifespan. The SC has high power density and longtime life cycle but low energy density. Presently, the SC is developing and may fully use in microgrid in the future. This paper studied the HESS topology of BESS and SC by considering the ramp rate power limitation to control the operation of HESS. The results showed the significantly improved for extending the lifespan of BESS by smooth of power exchanged and increased efficiency in the microgrid. The simulation is carried out in MATLAB-Simulink program.