An Economical Solar Water Pump With Grid and Battery Backup for Continuous Operation

In this article, the design and control of an efficient solar-powered, reduced-stage water supply system with both grid and battery backup for enhanced reliability are presented. The water pumps with permanent magnet and induction motors have demagnetization and reliability issues under harsh environments. Therefore, a reduced-component four-phase switched reluctance motor drive is utilized to improve the cost-effectiveness and reliability of the system. The back-up battery together with the grid supply will contribute to the uninterruptable power supply of the standalone solar water pump. The provision to feed the solar power back into the grid can offer an additional benefit to the consumers: to earn revenue. A single-phase voltage source converter is employed to preserve the desired power quality at the grid side. In the proposed structure, an intermediate maximum power point tracking dc–dc converter for the solar panel is removed to make the system more compact and efficient. Based on the converter's absence, a new control scheme is developed and presented. MATLAB/Simulink-based simulation is carried out first to validate the developed system and control strategy. The simulation results are further validated through experimental results obtained via a developed prototype.