Improved Control of Pressure Reducing Valves in Water Distribution Networks
Publication: Journal of Hydraulic Engineering
Volume 134, Issue 1
Abstract
The behavior of transients in water pipe networks is well understood but the influence of modulating control valves on this behavior is less well known. Experimental work on networks supplied through pressure reducing valves (PRVs) has demonstrated that, in certain conditions, undesirable phenomena such as sustained or slowly decaying oscillation and large pressure overshoot can occur. This paper presents results from modeling studies to investigate interaction between PRVs and water network transients. Transient pipe network models incorporating random demand are combined with a behavioral PRV model to demonstrate how the response of the system to changes in demand can produce large or persistent pressure variations, similar to those seen in practical experiments. A proportional-integral-derivative (PID) control mechanism, to replace the existing PRV hydraulic controller, is proposed and this alternative controller is shown to significantly improve the network response. PID controllers are commonly used in industrial settings and the methods described are easy to implement in practice.
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Acknowledgments
This work was kindly supported by the EPSRC under Grant Reference No. GR/S25715/01.
References
Åström, K., and Hägglund, T. (1994). PID controllers: Theory, design, and tuning, 2nd Ed., ISA International, Research Triangle Park, N.C.
Bergant, A., Simpson, A., and Vitkovsky, J. (1999). “Review of unsteady friction models in transient pipe flow.” Proc., 9th Int. Meeting of the IAHR Workgroup on the Behaviour of Hydraulic Machinery under Steady Oscillatory Conditions, IAHR, Madrid, Spain.
Bergant, A., Vitkovsky, J., Simpson, A., and Lambert, M. (2001). “Valve induced transients influenced by unsteady pipe flow friction.” Proc., 10th Int. Meeting of the IAHR Workgroup on the Behaviour of Hydraulic Machinery under Steady Oscillatory Conditions, IAHR, Madrid, Spain.
Brunone, B., Golia, U., and Greco, M. (1991). “Some remarks on the momentum equation for fast transients.” Proc., Int. Meeting on Hydraulic Transients with Column Separation, 9th Round Table, IAHR, Madrid, Spain, 140–148.
Brunone, B., and Morelli, L. (1999). “Automatic control valve-induced transients in operative pipe system.” J. Hydraul. Eng., 125(5), 534–542.
Buchberger, S. G., and Wells, G. J. (1996). “Intensity, duration, and frequency of residential water demands.” J. Water Resour. Plann. Manage., 122(1), 11–19.
Chaudhry, M. (1987). Applied hydraulic transients, Van Nostrand Reinhold, New York.
Driels, M. (1975). “Design of pressure transient control system.” J. Hydr. Div., 101(5), 437–448.
Garcia, V., Cabrera, E., Garcia-Serra, J., Arregui, F., and Almandoz, J. (2003). “Stochastic prediction of the minimum night flow demand in district metered area.” CCWI2003—Water supply management, C. Maksimović, D. Butler, and F. Memon, eds., Balkema, Rotterdam, The Netherlands, 665–672.
Karney, B. W., and McInnis, D. (1992). “Efficient calculation of transient flow in simple pipe networks.” J. Hydraul. Eng., 118(7), 1014–1030.
Prescott, S., and Ulanicki, B. (2004). “Investigating interaction between pressure reducing valves and transients in water networks.” Proc., 49th Int. Scientific Colloquium, O. Sawodny and P. Scharff, eds., Technische Univ. Ilmenau, Shaker, Aachen, Germany, 49–54.
Prescott, S., Ulanicki, B., and Renshaw, J. (2005). “Dynamic behavior of water networks controlled by pressure reducing valves.” CCWI2005—Water management for the 21st century, Vol. 1, D. Savic, G. Walters, R. King, and S. Khu, eds., Centre for Water Systems, Univ. of Exeter, Devon, U.K., 239–244.
Prescott, S. L., and Ulanicki, B. (2003). “Dynamic modeling of pressure reducing valves.” J. Hydraul. Eng., 129(10), 804–812.
Streeter, V., Wylie, E. B. W., and Bedford, K. W. (1998). Fluid mechanics, 9th Ed., McGraw-Hill, New York.
Unar, M., Murray-Smith, D., and Shah, S. (1996). “Design and tuning of fixed structure PID controllers—A survey.” Technical Rep.csc-96016, Faculty of Engineering, Univ. of Glasgow, Glasgow, U.K.
Zeigler, J., and Nichols, N. (1942). “Optimum settings for automatic controllers.” Trans. ASME, 64, 759–768.
Zeigler, J., and Nichols, N. (1943). “Process lags in automatic control circuits.” Trans. ASME, 65(5), 433–444.
Zhuang, M., and Atherton, D. (1994). “PID controller design for a TITO system.” IEE Proc.: Control Theory Appl., 141(2), 111–120.
Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 134 • Issue 1 • January 2008
Pages: 56 - 65
Copyright
© 2008 ASCE.
History
Received: Nov 22, 2005
Accepted: Mar 27, 2007
Published online: Jan 1, 2008
Published in print: Jan 2008
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