Energy Management Strategy for an Optimum Control of a Standalone Photovoltaic-Batteries Water Pumping System for Agriculture Applications

Pumping water using multiple energy sources is the ideal solution for supplying potable water in isolated or arid areas where there is no supply of grid power. In this paper, an effective control, and energy management strategy for a stand-alone photovoltaic-batteries water pumping system for agriculture applications is presented. The system is composed of solar photovoltaic panels as a primary energy source, and Lead-Acid batteries as a seconder energy source to supply the BLDC motor that drives the centrifugal pump. The energy management strategy uses an intelligent algorithm to satisfy the energy demanded by the motor, also to maintain the state-of-charge of the battery between safe margins in order to eliminate the full discharge and the destruction of the batteries. Drift is a major problem in photovoltaic systems; this phenomenon occurs when solar irradiation changes rapidly. Classical power maximization algorithms do not solve this problem, for this reason, a Modified Perturb & Observe (MP&O) has been implemented. The obtained results show a fast convergence performance to the maximum power point compared to the conventional Perturb & Observe (P&O). Computer simulation results confirm the effectiveness of the proposed energy management algorithm under random meteorological conditions.