With trains running at 97% punctuality and 100% availability from day 1, Gautrain has set enviable standards for the South African transportation industry. During the FIFA World Cup, Gautrain exceeded all expectations by ferrying well over 100 000 passenger and on 22 September 2010, the rapid-rail system celebrated carrying its one-millionth train passenger.
Behind the scenes of this impressive achievement, is a Station and Tunnel Management System (STMS) based on Wonderware Technology and implemented by the EPC business unit of engineering and construction solutions provider, Kentz.
The STMS is responsible for the monitoring and control of various subsystems like the ventilation and fire detection systems where it can cope with various scenarios with regard to fires breaking out at various locations. The STMS is also responsible for energy monitoring and control, escalator/lift monitoring and control as well as the management of the heating ventilation and air conditioning (HVAC), fire protection and dewatering systems.
Each of the different subsystems has to be monitored 24/7/365 and alarms and conditions need to be filtered so that only certain information is passed on to the OCC (operational control centre). Each of the stations need to be operated at a very high availability level and this in itself created an opportunity to design redundancy on the overall control room level down to station level should there be any communication failures.
System overview
The ArchestrA servers are located at the Midrand depot with clients situated at each station and connected via a fibre-optic network.
“Because of the distributed nature of Gautrain’s ‘shop floor’, reliable communications and redundancy are of primary importance,” says Sheldon Frade of Kentz. “Therefore the system has two modes of operation. In the OCC mode, everything is controlled from the Midrand depot. If network communication is lost, the system switches over to the station mode and there is no longer any communication with the servers.”
The passenger density at all stations is likely to increase with time, so safety is a primary concern with the early detection of malfunctions and prompt attendance to alarms mandatory. “We have made the HMI displays as readable as possible with services and their corresponding alarms overlaid on the station layouts,” says Frade. “For example, at the Sandton station, service status and alarm conditions are displayed on the backdrop of the side elevation of the facility. As soon as an alarm is detected, the system automatically navigates to its location and displays the plan view of the appropriate level. In this way, fault location is very rapid and guesswork is eliminated. The navigation bar at the bottom of each screen allows operators instant access to the required status and alarm information of each service.”
Challenges
Kentz was required to use a generic template specified by the principal contractors for setting up the individual stations and integrating them all under one umbrella. “The generic template to which we had to conform was new to us and different from any we would normally use with ArchestrA and the Wonderware range of products,” says Carl van Wyk of Kentz. “We also had to design a system that would have more than 99,7% up time.”
System development highlights
“The most compelling aspects of the project were the design and implementation of the newly created redundancy facilities and the flexibility of the ArchestrA technology to enable the design, engineering and installation of this project in a very demanding environment,” says van Wyk.
In addition, Kentz noted other benefits including the possibility of generating unrestricted custom navigation methods, the ability to add another (triple) level of redundancy if needed, the ability to use generic templates to speed up design time and the ease with which existing plants can be upgraded or expanded.
Benefits
* Engineered safety throughout the system – rapid location and display of alarms allows personnel to respond quickly to emergencies.
* Failsafe operation – the system is capable of triple redundancy if required.
* Maintained traffic density – The Gautrain operators have an STMS that meets and exceeds the performance criteria with respect to availability, thereby ensuring continued operation and minimising stoppages.
For more information contact Jaco Markwat, Invensys Operations Management, +27 (0)11 607 8100, [email protected], www.iom.invensys.co.za
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