Online Non-Intrusive Efficiency Monitoring of Pumping Systems

Moving toward a sustainable energy future requires improving the efficiency of energy systems. The fact that about 22% of industrial electricity is consumed by induction-motor-driven centrifugal pumps, highlights the importance of continuous monitoring of such systems to ensure they are operating at their best efficiency points. This results in the overall reduction of energy consumption and consequently lowers the carbon footprint of pumping systems. This paper presents a non-intrusive approach towards estimating the efficiency of the whole motor pump chain. The motor efficiency is calculated using only motor electrical signals along with the nameplate information. To estimate the pump efficiency, a hybrid method is adopted which uses the pump characteristic curve, impeller speed, and affinity laws. Both estimation algorithms are based on electrical signature analysis (ESA) which requires only motor terminal quantities i.e. current and voltage. The proposed methods are tested on laboratory setups and the experimental results show their accuracy in estimating the efficiency of induction-motor-driven pumps. Given the non-intrusive nature of the proposed method, a simple data acquisition system to acquire motor current and voltage signals along with a microprocessor to implement the algorithms discussed here can be integrated into a single affordable board to be used in utilities for continuous efficiency monitoring purposes.