Harnessing Maximum Power from Solar PV Panel for Water Pumping Application

Abstract

The problem of fast depleting fossil fuels is triggering exploration of alternate sources of electricity. Among such sources, Solar Photo Voltaic (PV) energy is gaining prominence due to its plentiful availability. Water pumping is an important application of solar PV power. However people are not opting for it in large numbers as the ‘cost per watt’ for solar pumping systems is high. The cost component can be reduced by harnessing more power per unit installed capacity of the solar panel. One method of realising this is by Maximum Power Point Tracking (MPPT) wherein a Power Electronic (PE) converter is used to match pump with the PV panel. Present paper deals with the MATLAB based simulation study of solar PV driven Permanent Magnet (PM) DC motor (brushed) Pump System. Two cases are considered: a) System without MPPT b) System with MPPT. It is shown that by varying duty cycle of the converter at different radiation levels, the pump speed and hence the useful mechanical output can be enhanced with MPPT. The simulation study reveals that the output power becomes the maximum when the motor voltage becomes the maximum. Hence it is proposed that the motor voltage can be used as a control parameter for varying the duty cycle of the converter in achieving maximum output.