Water Journal : Water Journal November 2013
WATER NOVEMBER 2013 52 Feature Article start. However, the automatic start of the second pump was suppressed during this initial commissioning test. MODELLING SUPPORT DURING SYSTEM COMMISSIONING The Southern System is complex and can be operated in numerous con gurations of sources, supply points and ow directions for the water. In order to commission the integration works for the new desalination plant within the allotted time, system con gurations were divided into shortlists of Priority 1, 2 and 3 system con gurations. The priority of the system con gurations was based on how critical a particular con guration is to the day-to-day operation of the system. The reduced lists of system con gurations still consisted of seven Priority 1 con gurations, 17 Priority 2 con gurations and 29 Priority 3 con gurations. Although commissioning tests had to be conducted on the real system for a number of con gurations, the agreement between the model results and the SCADA data was so close that a signi cant number of tests could be conducted with the validated model. This greatly reduced the time and effort, and hence overall cost, required to complete the system commissioning. The validated model of the Southern System and Ravenswood Pump Station's control systems was also used to simulate commissioning tests with the model rst, before undertaking the tests on the real system. This gave commissioning personnel insight into the expected performance of the system and reduced the risks of conducting the commissioning tests on a live system with customers connected. CONCLUSION This article describes the bene ts of the use of control system modelling as a tool in the design and commissioning of pump station control systems. In the early design stages control system modelling provides the means to explore the dynamic behaviour of a water transfer system and to compare the performance of different control strategies. During detailed design, the control logic for pump station control systems can be developed and tested in detail on the model of the water transfer system and pump station control system. This reduces the risk of delays and last minute design changes to the control logic due to unexpected issues in the commissioning stage. In the commissioning stage, a validated control system model can play a vital role by reducing both the risk and the number of commissioning tests conducted on the real system. In the case of the integration works for the Southern Seawater Desalination Plant, the control system model for Ravenswood Pump Station contributed to getting the integration works commissioned on time and within budget. As such, the use of control system modelling can greatly reduce the time and effort, and hence overall cost, required to complete system commissioning. ACKNOWLEDGEMENTS The Authors wish to acknowledge the Water Corporation and GHD for their permission to publish this paper. Ravenswood Pump Station was planned by the Water Corporation, designed by GHD and commissioned by the Water Corporation with support from One Stone Consulting. The Authors also wish to acknowledge Chengchao Xu, Anthony McLaughlin, Mark Holmes, Wayne Keenan and Angelmo Shanmuganathan, and all other personnel involved in the planning, design and commissioning of the SSDP Integration Works. WJ THE AUTHORS Eelko Van Der Vaart (email: eelko@ onestoneconsulting.com.au) is the Director and Principal Consultant of One Stone Consulting. He is a Civil Engineer with 13 years of experience in the water industry, both in Australia and in the Netherlands. Faris Hernich (email: faris.hernich@watercorporation. com.au) is a Civil Engineer with over 24 years of experience in the water industry. He provides leadership of an infrastructure planning function and manages the Operational Modelling Group in the Water Corporation. REFERENCES Bequette B (1957): Process Control, Modelling, Design and Simulation, Prentice Hall International Series in the Physical and Chemical Engineering Sciences. Deltares (2008): Wanda 3 Help -- User Manual. Deuerlein J, Simpson AR & Gross E (2008): The Never Ending Story of Modelling Control Devices in Hydraulic Systems. 10th Annual Symposium on Water Distribution Systems Analysis, American Society of Civil Engineers. GHD (2009): Southern Sources Transfer System Modelling -- Control System Analysis Ravenswood Pump Station. System Modelling Report for Water Corporation. Infrastructure Planning Branch (IPB) (2009): IWSS Southern Source System -- Southern Seawater Desalination Plant Stage 1 (50 GL.a) 2011. Water Corporation Planning Report. Van Der Vaart E, Holmes M, Hernich F, McLaughlin A & Xu C (2010): Dealing With The Complexities Of Integrating Perth's Second Desalination Plant. Ozwater'10, Brisbane. Van Der Vaart E, Xu C & Hernich F (2012): Control System Modelling for a Large Scale Pumping Station. 14th Annual Symposium on Water Distribution Systems Analysis, American Society of Civil Engineers. Figure 7. Model validation -- Dandalup Bank delivery head and suction head. Figure 8. Model validation -- Dandalup Bank transient duty point.
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