Characterization of photovoltaic pumping system model without battery storage by MATLAB/Simulink

Under normal operating conditions, the flow rate of a solar pump fed by a photovoltaic array follows the variations of the irradiance. However, the flow rate of a photovoltaic pumping system coupled to a water filtration unit should be constant under a constant pressure. So, the combination of solar batteries with a photovoltaic array is required. This paper presents a specific structure of the P & O algorithm for controlling a boost converter inserted between the photovoltaic array without batteries and the driving motor of a centrifugal pump. The simulation results in MATLAB/SIMULINK with ode23t solver show that blocking of the duty ratio of the control pulses of the boost converter enables to maintain a constant output voltage, even if the irradiance varies. Thus, for a duty ratio locked between 0.79 and 0.9, the output voltage of 236 V is obtained, for a flow rate of 1.08 l/s under a pressure of 5.8 bars.