PERFORMANCE OF OVERSIZED PUMPS CONTROLLED BY VARIABLE FREQUENCY DRIVES IN WATER SUPPLY SYSTEMS

Abstract

Reducing water and energy consumption is an essential condition for reducing the operational costs of water supply systems (WSS). The use of pumping systems driven by variable frequency drives (VFD) is one of the most suitable alternatives to optimize the pressurization of the distribution networks and, consequently, reduce the consumption of electricity and water losses. This article aims to analyze the performance of oversized pumps, driven with variable frequency drives, from WSS. The work was carried out in two experimental setups that have oversized pumps. The methodology consisted of evaluating data collected in experimental tests using hydraulic and electric meters. Tests were realized for different operating conditions of the systems, with the variation of the rotation of the pumps, in order to obtain the pump efficiency curve according to the VFD output frequency. The results demonstrated that the use of variable frequency drives proved to be an alternative to increase the energy efficiency of the evaluated systems. It was observed that the highest efficiencies were recorded in the lowest frequency bands (30 Hz and 35 Hz), while in the values close to the nominal frequency (45 Hz to 60 Hz) there is little variation in the efficiency values.