Data Reconciliation on the Complex Hydraulic System of Canal de Provence

A data reconciliation module, based on the measurements from the hydraulic network, has been recently developed and implemented in the supervisory system of the Societe du Canal de Provence (SCP). The software has initially been used daily to check the measured flow on the main canal. The data reconciliation occurs just after the measurement process. The measurement network on the hydraulic system includes many sensors subject to failure or deviation and is spread over a huge area. In addition, discharge and volume measurements in open-channel hydraulic networks are characterized by large uncertainties. The objective of the data reconciliation is to take advantage of information redundancy on a system to make a cross-check of real-time measurements. By using this information redundancy, a data reconciliation module allows detection of inconsistent measurements and measurement deviations and provides corrected values whether the initial measurements are valid, biased, or invalid. A derived consequence is better scheduling of the maintenance of sensors. The results are corrected values for measured variables and proposed values for nonmeasured quantities. A statistical analysis of the results is performed. This analysis allows evaluation of the uncertainties attached to the estimated flows and volume values. It allows also detecting invalid measurements and drift of sensors and making decisions about which maintenance operations to perform.