Investigations on solar water pumping system with extended self boost quasi impedance-source inverter

Abstract

This paper proposes the new quasi impedance source inverter with increased boosting capability for solar water pumping system. The extended self boost quasi impedance source inverter has the advantage of increased boosting potential compared to the Z-source inverter and is expandable. This topology uses the same modulation technique that is adopted for the original ZSI. The proposed self boost inverter boosts the low voltage output of the PV modules used in the water pumping system thus reducing the number of PV panels required for the system. Therefore the system cost and space requirements are reduced considerably. A complete model of the solar water pumping system with the proposed inverter is developed in Matlab/Simulink. The system is analysed with simple boost method and the modulation index to obtain the optimum output is estimated through simulation. The discharge of the pump is analysed for varying solar intensities. The effect of variation in the modulation index is also studied in Simulink environment and the results are presented.