Contribution to the improvement of a solar pumping system based on asynchronous machine

Abstract

Irrigation based on photovoltaic power is competitively priced compared to fossil fuel. Thus, a lot of articles present and study different photovoltaic pumping systems structures. In fact, this paper revolves around sizing and simulating a three phase photovoltaic pumping system based on photovoltaic array, DC-DC step up converter, three phase inverter, filter, induction motor and a submersible pump of 1.1KW. Solar array power is sized to 1.2KW includes the losses of the system. The system productivity is optimized by disturb and observe maximum power point tracking control programmed in Matlab software. It tracks the maximum power generated by a photovoltaic array at different irradiance and temperature value and controls the boost to work at the optimum point. The boost converter is designed to boost the photovoltaic voltage at the output. The DC-AC inverter is controlled by sinusoidal pulse width modulation. It drives the output voltage harmonics to higher frequencies and facilitates filtering. The LC filter produces a sinusoidal signal of reduced ripples. The performances of the sized system are evaluated by simulation under Simulink software. Simulation results prove that the system seeks and reaches the maximum power that can be supplied by a photovoltaic array. Furthermore the motor speed gets to the nominal value under optimal climatic conditions. A change of climatic conditions affects the motor speed and torque to move from the nominal values.