A new pump selection method for large-power PV irrigation systems at a variable frequency

Abstract

This paper presents a new method for selecting a pump for large-power PV irrigation systems working at a variable frequency. This can have a significant impact since the traditional way of selecting the pump is based on maximizing the efficiency of pump in the duty point at a certain single operating frequency, which is not useful for PV irrigation systems working at a variable frequency. The proposed method starts by considering the pumps with H-Q curves with a high slope and the duty point in the right-hand third of the curve to assure a wide range of operating frequencies. Then, the efficiency within the whole range of frequencies is evaluated. An example of a performance comparison between the pumps selected with the new and traditional methods has been carried out. Results show that by using the new method, the yearly volume of water pumped increases by 7.2-21.0%) and the pump efficiency by 4.3-5.3%). Finally, it is important to mention that the proposed method has already been implemented in the SISIFO tool, able to simúlate PV irrigation systems.

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Multiobjective Optimization Design and Experimental Investigation on the Axial Flow Pump with Orthogonal Test Approach

“…Pump is a kind of widely used machinery with universal applications which accounts for almost 22% of the world's energy consumed by electric motors [1][2][3][4]. Axial ow pumps, as the main pump type applied in low-lift and large-ow pumping stations, have attracted increasing attention in eld irrigation and water diversion projects [5][6][7].…”

Optimisation of the distribution of power from a photovoltaic generator between two pumps working in parallel

“…In practice, the selection of the pump of a photovoltaic pumping facility must be carried out taking into account that it works at a variable frequency. Almeida et al (2018b) proposed a method for selecting pumps suitable for PV pumping applications based on considering not only the efficiency at the maximum operating frequency but in the whole range of operating frequencies.…”

“…These solutions were developed to overcome the PV peak power due to the passing clouds and to the imbalance between PV production and water needs. Almeida et al (2018b) reduced power threshold to start pumping achieving longer periods of pumping. They proposed a pump selection method based on considering the efficiency in the whole range of operating frequencies.…”