Modelling and performance analysis of a PV system with lithium-ion battery for autonomous micro-grids

The dynamic performance of a stand-alone photovoltaic (PV) system designated to supply a micro-grid is strongly influenced by sunlight and temperature. The variable nature of irradiation and temperature affects energy production especially when associated with unpredictable variations of the load. To compensate for these load and production fluctuations, a stand-by energy storage system is required. This work focuses on the modeling and performance analysis of a hybrid PV-battery system (lithium ion) connected to a direct current (DC) micro-grid. Maximum power point tracking (MPPT) and proportional integral (PI) controls are used to extract and stabilize the maximum power of the photovoltaic generator at any time. The study discusses the performance of each autonomous hybrid subsystem validated by simulations and performed under severe weather conditions and a variable DC load. The obtained results show the importance that can have a SS by ion-lithium battery in an autonomous micro-grid of solar energy production.