Technical assessment of power interface to utilize untapped power of decentralized solar pumps for positive impact in livelihoods

Abstract

Abstract This paper proposes the implementation of a power electronics interface for driving agricultural loads. The interface would utilize the untapped power generated by pre-installed solar-photovoltaic (SPV) based pumping systems during non-pumping periods. This architecture is used to increase the percentage utilization of the SPV pumping system, which is currently at around 50 %. The implemented system includes a dual stage converter, consisting of a boost converter and an H-bridge inverter, to facilitate the interface between low-voltage (LV) SPV systems and single-phase AC agricultural loads, while maintaining the desired voltage level. The key advantage of this system is its transformer less operation to boost SPV output from 90 V DC to 220 V AC, resulting in reduced size and cost. This paper presents an analysis of the operating modes, system modeling, validation in simulation, and experimental implementation of 1 kW system. Additionally, an improved step-size perturb and observe (P&O) technique is employed in the implemented interface to extract optimum power from a SPV. This interface is suitable for incorporating an off-grid SPV pump to power other loads during non-pumping and sunny hours. Furthermore, a comparison of the proposed interface with existing structures demonstrates operational superiority. Furthermore, the system can be efficiently used to drive various single-phase agrarian loads for farmers’ use in unelectrified remote areas.