Energy Management of PV-Batteries System for a Rural Micro-Grid Application in Guinea

Integration of solar energy in stand-alone microgrid applications is an attractive solution for improving access to electrification in remote rural areas and reducing dependence on the main power grid. This paper proposes a control strategy to manage the energy of a hybrid system comprising photovoltaic (PV) solar panels and energy storage batteries. The aim is to maximize the use of PV solar energy by using a PV voltage model that considers the variations of the series resistance as a function of solar irradiance and operating temperature. This ensures optimum operations of the microgrid and improves energy efficiency. The strategy adopted is based on a dual approach that combines a maximum power point tracking algorithm with incremental conductance to extract the maximum power from the solar panels, and an energy management system based on rules control. The proportional-integral controller regulates the batteries power flow to maintain a stable DC-bus voltage within the micro-grid. System performance is evaluated in the Matlab/Simulink software environment for different load profiles and sunlight conditions. The simulations results show a significant efficiency of the control system with PVs power fluctuations mitigating by the batteries to reduce the current stress for the load.