Leakage location in pipelines by minimal order nonlinear observer

Introduces a method to locate the leakage position in a pipeline estimating flows deviations with minimal order nonlinear observers when only measurements at the extremes of the duct are available, and calculating the leakage position using a set of nonlinear equations at the leak point. Taking into a account that the fluid model in the duct is given by a set of partial differential equations, a finite dimension nonlinear model of minimal order for FDI is obtained assuming that flows can be measured at the end points of the line, pressions are the control variables, and require the uniform observability condition for each of the outputs. The system properties of uniform observability and affinity in the control allows us to improve the residuals generator response previously reported in the literature by linear observers. Moreover, the residuals generator design problem is simplified, since two independent simple nonlinear estimators for flows deviations which are sensitive to any leak can be designed using either fixed or varying gain observers. For the leakage position estimation a set of three nonlinear equations must be on-line solved in which the unknowns are leak rate, its position and pressure at the leak position. The performance of the approach is demonstrated using simulated and experimental data taken from a water pilot pipeline