Energy Management of PV-Grid-Integrated Microgrid with Hybrid Energy Storage System

Abstract

The short-term variability in power produced by grid-integrated photovoltaic (PV) plants can adversely affect the power quality and reliability of the system. Hence, the variability of the generated power is one of the major challenges to integrating this solar resource into the electricity grid. The irregular nature of renewable sources and unpredictable load changes require high-energy and high-power density storage devices in the current microgrid (MG) environment. In this paper, an energy management scheme (EMS) is proposed for the control of solar PV fluctuations using ramp-rate control with a hybrid energy storage system (HESS). The ramp-rate control in the system mitigates fluctuating PV power and improves system reliability. The proposed EMS has the following key advantages: effective power-sharing between energy storage devices (ESSs), faster regulation of DC-link voltage to generation and load uncertainties, effective power distribution between battery and grid-based on the battery charge state, and reduced charging/discharging rate for battery current during steady and transient state power fluctuations. The performance of the system was validated using the MATLAB/Simulink environment.