Logical consensus control for a smart water distribution system

Abstract

Urban water distribution systems (WDS) should be designed not only for the safe provision of services but should also be resilient to unexpected threats that may lead to catastrophic system failure. Outdated facilities, water shortage, limited water resources, global population growth, industrial revolutions, global warming, and climate changes including flash floods and prolonged droughts are the potential challenges to the urban WDS. These challenges urge many countries to strategize and seek innovative ideas to secure a sustainable supply of water. With the emergence of the Internet of Things (IoT), cloud computing, big data analytic, and smart sensors, massive real-time information can be remotely collected and monitored. Capability in utilizing data analytics in real-time operation promises greater efficiency in WDS management. Thus, there is an increasing need to leverage IoT-based technologies to ensure the WDS infrastructure and operation are sustainable and resilient. Therefore, the present study develops an automated real-time decision-making mechanism for a smart WDS. A logical consensus algorithm is developed to coordinate multiple sensors, controllers, and actuators by utilizing real-time information on the overall system. The logical consensus is a binary triggered detection system that is suitable for WDS applications that requires opening and closing valves to optimize the normal operation and to react efficiently upon failure occurrence. The framework proposed is based on the algebraic graph theory, which consists of visibility, communication, and reachability matrices and the iteration rules designed based on the cellular automata (CA). The CA is a dynamic structure of a discrete computation model that is fundamentally based on local interaction and computation. Two different physical WDS layouts are considered; the basic combined configuration and the actual Balok water supply layout which represent multiple combinations of branch and grid configurations. The proposed algorithm is designed and simulated using MATLAB programming and mathematical computing software. To analytically validate the convergence achieved in simulation, the reachability analysis is conducted using Hamiltonian Cycle and full rank matrix. The simulation result shows that the proposed algorithm has a significant advantage in terms of convergence time by converging 45% faster compared to the benchmark algorithm which is more computational demand due to the combination of several rules. Based on the developed algorithm, a large number of devices including valves can be activated and de-activated simultaneously. The implementation of the CA in the logical consensus control algorithm has increased the sustainability of WDS operation, particularly at a partial operation. The results of this study further broaden the application of logical consensus with CA in a control system, and most importantly, the developed algorithm will be useful to the development of the next generation of resilient and efficient WDS.