Yorkshire Water

ABB

United Utilities

EPSRC

NEPTUNE MONITOR

CONTROL

OPTIMISE

Supervisory Pressure Control Report D2.6

by

Hossam AbdelMeguid, Piotr Skworcow and Bogumil Ulanicki Process control - Water Software Systems, De Montfort University

and

Ping Li, Ian Postlethwaite and Emmanuel Prempain Department of Engineering, University of Leicester

Table of Contents

1. Introduction 2. Identification of the hydraulic models for supervisory pressure control 3. Methodology of supervisory pressure control 4. Pressure control off-line study 5. Discussion 6. Hardware implementation considerations 7. Conclusions

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Abstract In this report, applying and developing of supervisory pressure control schemes for Staincliffe area is discussed. Based on the provided schematic diagram of the Staincliffe area, and the available pressure and flow data of 6 DMAs, the aggregated model was developed and the hydraulic model was built in both FINESSE and EPANET software packages. The simulation results of the aggregated model were validated against the real data. As well the pressure control algorithm was applied on the developed aggregated model, to develop steady state pressure control strategies for that area. Also, the possible solutions for supervisory pressure control, hardware implementation and further course of action are proposed. The proposed hardware implementation does not require Technolog to spend any resources neither to disclose any technical details other than normally made available to YWS.

1. Introduction The development of supervisory pressure control schemes covering wide areas, and has a crucial role to play in background leakage reduction, burst reduction and quality of supply; stabilising pressure for customers; reducing the demand for energy and reducing overall water supply costs (Cembrano et al., 2000). The design of pressure control schemes is currently a manual process, with zones being defined using engineering judgement aided by network computer simulation models. Zones are based on existing DMAs, which may be configured in ways that make them ineffective for pressure management. The future performance is critically dependent on zone formation. There is clearly substantial benefit to be gained from a tool that will identify the best zone configuration for any network which can be linked to on-line pressure management and will result in reduced leakage (Vairavamoorthy and Lumbers, 1998; Ulanicki et al., 2000; Almandoz et al., 2005; Marunga et al., 2006). The current industrial approach to pressure control is to use a local control (DMA level) for a single inlet DMA and considers steady-state aspects of the control.

1.1. Aim and Objectives Aim: Introduce a supervisory pressure control system to minimise leakage, energy consumption and customer interruptions. Objectives: • To evaluate and plan enhancement of existing telemetry systems including measurements and actuation • To integrate the supervisory system with the regulatory control level and the decision support system • To develop steady state pressure control strategies

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6.2. Recommendations To develop accurate aggregated model and carry out the off-line study, the following accurate data are required to be provided by YW: •

Time series data (typically on 15 minutes intervals):

•

PRV inlet and outlet pressure (logged by Modulo)

•

Flow into the area (from flowmeter)

•

Pressures and flows at the inlet of each DMA.

•

Pressures at critical points (from Cellos), provided at the same time instances as signals from PRV

•

Metered or aggregated demand information

Other data: •

An overall diagram of the area

•

Elevation of all nodes

•

Any additional information useful for building model from measurements (e.g. interaction between the considered nodes, leakage level, etc).

Above listed data should be provided for at least one week period on 15 minutes intervals base.

6.3. Future Work Subjected to a complete and accurate data provided by YWS, the aggregated hydraulic model will be redeveloped as suggested in the 6.2. Recommendations section. The pressure control algorithm will be applied to estimate the optimal PRV outlet head and assess any potential saving in the imported flow by the leakage reduction.

7. Conclusion Based on the provided schematic diagram of the Staincliffe area, and the available pressure and flow data of 6 DMAs, the aggregated model was developed and the hydraulic model was built in both FINESSE and EPANET software packages. The simulation results of both software packages are the same and produce a negative pressure at some nodes during time period from 06:00 to 07:00 am. During validation of the developed model, by comparing the simulation results with the measured data, a significant difference between the simulation results and measured data is observed, due to several quantitative and qualitative problems in the provided data. It is concluded that the developed model is not accurate and that another data set needs to be provided. Nevertheless, an attempt was made to apply the pressure control algorithm on the developed aggregated model, but the results show that the optimal PRV outlet pressure is always higher than the current operation pressuretherefore no leakage reduction is achieved. As a result, it is not possible to evaluate or assess any potential benefits of applying the supervisory pressure control on the Staincliffe area using the provided data and the developed model.

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Possible solutions for supervisory pressure control hardware implementation and further course of action were proposed. The proposed hardware implementation does not require Technolog to spend any resources neither to disclose any technical details other than normally made available to YWS.

References AbdelMeguid, H., Bounds, P., and Ulanicki, B. (2007). "Pressure Management Report, Supply zone DMA E067-Waterside." NEPTUNE Deliverables, Process Control - Water Software Systems, De Montfort University, Leicester, UK. Almandoz, J., Cabrera, E., Arregui, F., Cabrera, E., and Cobacho, R. (2005). "Leakage Assessment through Water Distribution Network Simulation." Journal of Water Resources Planning and Management, 131(6), 458-466. Bergant, A., Vitkovsky, J., Simpson, A., and Lambert, M. (2001), "Valve induced transients influenced by unsteady pipe flow friction." 10th Int. Meeting of the IAHR Workgroup on the Behaviour of Hydraulic Machinery under Steady Oscillatory Conditions, IAHR, Madrid, Spain. Brdys, M.A., and Ulanicki, B. (1994). Operational Control of Water Systems: Structures, Algorithms, and Applications, Prentice Hall. Brunone, B., and Morelli, L. (1999). "Automatic control valve–induced transients in operative pipe system." Journal of Hydraulic Engineering, 125(5), 534-542. Cembrano, G., Wells, G., Quevedo, J., Pérez, R., and Argelaguet, R. (2000). "Optimal control of a water distribution network in a supervisory control system." Control Engineering Practice, 8(10), 11771188. Marunga, A., Hoko, Z., and Kaseke, E. (2006). "Pressure management as a leakage reduction and water demand management tool: The case of the City of Mutare, Zimbabwe." Physics and Chemistry of the Earth, 31 (15-16), 763-770. Prescott, S., and Ulanicki, B. (2004). "Investigating interaction between pressure reducing valves and transients in water networks." 49th International Scientific Colloquium, O. Sawodny and P. Scharff, eds., Technische University, Ilmenau, Shaker, Aachen, Germany, 49–54. Prescott, S.L., and Ulanicki, B. (2008). "Improved control of pressure reducing valves in water distribution networks." Journal of Hydraulic Engineering, 134(1), 56-65. Ulanicki, B., Bounds, P.L.M., Rance, J.P., and Reynolds, L. (2000). "Open and closed loop pressure control for leakage reduction." Urban Water, 2 (2), 105-114. Ulanicki, B., AbdelMeguid, H., Bounds, P., and Patel, R. (2008). "Pressure control in district metering areas with boundary and internal pressure reducing valves." 10th International Water Distribution System Analysis conference, WDSA2008, 17-20 August, The Kruger National Park, South Africa. Vairavamoorthy, K., and Lumbers, J. (1998). "Leakage reduction in water distribution systems: optimal valve control." Journal of Hydraulic Engineering, 124(11), 1146-1154.

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