Implicit state-estimation technique for water network monitoring

Abstract

This paper presents a new implicit formulation of the standard weighted least squares (WLS) state-estimation problem for water networks with very low measurement redundancy. The formulation is based on the loop equations and the state variables are the unknown nodal demands. The minimisation problem is solved using a Lagrangian approach. It is shown that the method can be applied to weak demand indicators, such as property counts, rather than direct demand information which is often unreliable. Furthermore, a new leak detection scheme is derived from the method. This method is investigated under idealised noise-free conditions in order to demonstrate the principles and to gauge the potential of the scheme. The application of the scheme in more realistic circumstances of uncertainty is also discussed.