Implementation of Photovoltaic water pumping system with optimization controls

Abstract

To increase the output efficiency of a photovoltaic (PV) generation system, it is important to have an efficient maximum power point tracking (MPPT) technique. This paper describes the analysis, design and implementation of efficient tracking methods for a stand-alone PV generation system, using two approaches: The constant voltage (CV) method is based on the optimum voltage that is considered as a reference value; and the Increment Conductance (Inc-Cond) MPPT control. The output controller can adjust the duty ratio of DC/DC boost converter where its output feeds a set of Moto- pump via a DC/AC inverter. This paper presents a detailed experiment of the two implementation techniques, based on system performance characteristics, and energy utilization for standalone PV pumping systems. Contributions are made in several aspects of the whole system, including converter design, system simulation, controller programming, and experimental setup. The resultant system is capable of tracking MPPs accurately and rapidly without steady-state oscillation, and its dynamic performance is also satisfactory. MATLAB / Simulink and dSpace DS1104 are used to carry out studies and implement algorithms. The two proposed methods have been validated by implementation the performance of the PV pumping systems installed in the reach laboratory in Tunisia. Experimental results indicate the feasibility and the improved functionality of the system.