Energy-efficient local control strategies for pumping stations with variable-speed pumps: A practical model-based approach

Pumping activities in water distribution systems are one of the major energy-consuming processes in water supply systems. As such, optimal control strategies are developed to optimize the energy consumption of these systems. In this study, we propose a novel model-based local control strategy for pumping station operation that includes multiple variable-speed pumps. Unlike the state-of-the-art, which primarily focused on centralized control schemes, the proposed local control schemes were developed while highlighting the practicality and ease of implementation that does not necessitate infrastructure investment from the end-users. Firstly, we formulated a control algorithm that simulates the current practice. Next, an optimization algorithm was developed to achieve minimum energy operation considering the head and efficiency curves of the pumps. Unlike current practice, the salient feature of the developed algorithm is that it utilizes the physical properties of the systems to ensure hydraulic feasibility while sustaining the required pressure setpoint. Furthermore, the developed approach can account for practical operational constraints such as bounds constraints on the speeds, pump availability constraints, and time gap constraints to prevent frequent pump changes. The methodology was demonstrated using a realistic case study, showing a reduction of energy consumption of about 10% compared to the current practice.