Upgrade of instrumentation Information from Invensys

SSE, the operators of the The power station, needed to address the obsolescence of its existing DCS and to provide an expandable solution to extend the working service life of the power station. The vendor needed to deliver the total upgrade solution in time for a planned major shutdown and in parallel with other plant projects, with minimal commissioning time

The has a history of changing familiarisation and the facility now has a maintenance activities as well as other course over the ages, with mention of its rigorous test-bed for process testing. expansion projects. Furthermore, site meanderings even in the works of William works needed to take place with minimal Challenges Shakespeare. Once a major commercial disruption to the outage programme. A waterway marking the traditional boundary These included incomplete loop drawings, risk assessment of the project requirement between Northern and Southern England, faded conductor identity and the risk of identified two key areas of concern: the the river is relatively stable today and is the human error during I/O change-out, which I/O upgrade and application software were considered significant upgrade migration. For the I/O upgrade, plant source of recreation and drinking water, as obstacles. Limited documentation engineers at Keadby cited challenges well as cooling water for a large number available on existing software applications such as faded conductor identification of and gas fired electrical power presented software migration and testing labels, incomplete loop drawings, human plants along its route. One of those plants, dilemmas for the project team. error risks and the potential impact on the Keadby Power Station at in outage programme associated with on- North Lincolnshire, is operated by SSE, one Shining the light on a new infrastructure site rewiring and testing of approximately of the largest energy companies in the approach 6000 loops. United Kingdom. The Keadby plant, which Before the upgrade, the majority of the Although the existing system had began commercial operation in 1996, is plant was operated by a site-wide Emerson been reliable in the past, problems a 720 MW combined-cycle WDPF (Westinghouse distributed process were emerging. according to Hugh generating facility. family) DCS system. A moderate-sized Ferguson, C&I engineer at Keadby Power control system, this included 26 fault- The plant includes two General Electric Station and project manager for the DCS tolerant controllers, 12 HMI workstations, frame 9FA gas turbines, one Alstom steam upgrade project. An increasing number including one historian and comprising of components were either no longer turbine, two Babcock three-pressure waste 6046 hardwired I/O, eight control level heat recovery boilers and a Siemens data links (Modbus, Allen-Bradley DH+, available or no longer repairable. Plus, GT10B auxiliary gas turbine. It is maintained GE-GSM); three supervisory level data controller memory was near capacity and and operated by a staff of 53 including links (Modbus-TCP, ODBC, OSI-PI); and 190 most of the data highway bandwidth was managers, engineers and technicians. process screens, including approximately already utilised. When SSE management realised the 130 overlays and 48 sequences. Migration of the application software was facility's distributed control system was SSE engineers initially identified 7 key also considered a potential problem area. approaching plant-wide obsolescence, criteria for the DCS upgrade project. Top Documentation was limited and there were the company chose Invensys operations of the list was that the upgrade had to be no control narratives available. This meant management to upgrade the plant to a completed in time for a scheduled major that the application software itself had to more flexible, scalable and supportable plant outage and the system migrated be used as the source for the migration solution. with minimal site commissioning time. process raising concerns over the potential In addition, the new DCS system had to for human error, the skill-sets required and Solutions and products address the pressing obsolescence issues the functional acceptance test criteria. Solutions included : and remain current for the remainder of the plant's expected service life. Sufficient Based on the potential obstacles, it was not  InFusion Enterprise control system (the expandability in terms of controller clear whether there was an alternative to first major InFusion solution in the UK) memory, I/O capacity and network upgrading to Ovation, the next generation of the WDPF platform. However, because  Foxboro I/A series distributed control bandwidth together with simplified online of concerns over software acceptance system configuration was also considered a key requirement. Because of the potential testing and continued support for the  SimSci-Esscor ROMeo online impact on operating procedures and other existing I/O hardware, SSE decided to performance suite human factors, engineers also specified go out to Tender for the project. Six DCS  SimSci-Esscor dynamic simulation suite that the new plant solution should maintain vendors pre-qualified for the proposed results the existing control strategies and HMI migration project, with four vendors asked interface standards. to present formal technical evaluations of The Invensys solution was delivered on time their proposed solutions. for the planned outage and within the Upgrading systems in harmony with SSE budget for the project. The upgrade Invensys operations management was existing operations and upgrades addressed both the obsolescence and ultimately selected by SSE because of their expandability issues. Plant personnel As planning progressed, it became proven plug-in I/O card migration solution realised major benefits of simulation, clear that the DCS upgrade had to be for WDPF, WDPF migration expertise, in- including improved operator training and conducted in parallel with essential major house simulation capabilities and the

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incorporation of a model-based plant an alternative to the existing system start-up, steady-state operation and simulator for application software testing was a viable option. Simulation is also shutdown by an experienced Keadby and operator training. proving particularly useful at resolving operator. Once it had been demonstrated hard-to-replicate problems and was that it was possible to operate the plant Mastery of the migration process invaluable in leveraging the experience in accordance with existing operating Invensys WDPF migration-style FBMs are of plant operators during migration of the procedures, SSE gave the "green light" to a plug-in replacement for WDPF Q-Line application software. proceed with the site installation phase of I/O cards which allow the existing WDPF the DCS upgrade. I/O racks, power-supplies and field wiring Initially, migration of the DCS application to be retained and re-used by the new software and development of the OTS A plan well-devised is a plan Foxboro IA system. From an IA system plant model were undertaken as separate, well-executed parallel activities by separate project perspective, these modules appear The project was delivered in time for teams. Once completed, these two identical to standard Foxboro 200-series Keadby's planned shutdown and within FBMs. elements were then combined to allow SSE budget parameters. The equipment functional testing in the factory, prior to Semi-automated tools were offered to upgrade was completed in less than 13 installation at site. days, compared with the 18 days that migrate the Westinghouse application to were scheduled. There was only one minor the InFusion environment. InFusion is the Once the system architecture and two-hour delay to the return-to-service Invensys delivery mechanism for enterprise hardware and been specified, the DCS programme attributable to the migration control and consists of the hardware and team began by developing migration to the new DCS. The unique Invensys tools and carrying out code analyses; software components necessary to provide migration solution with plug-in I/O modules a true aggregated view of information breaking the application down into allowed for unparalleled minimal plant across an organisation, enabling a robust HMI components, interlock/protection downtime for the project. foundation for collaboration between logic, sequences, unique strategies and people, processes and systems. typicals. Migrated DCS components were In addition, the expandability issue has then tested on a modular basis via a been resolved as the new DCS now The SimSci-Esscor dynamic simulation combination of code reviews and basic supports up to 2000 nodes and the central suite provides both model-based plant I/A series functional testing. processor loading is less than 25% of simulation and a platform for enabling a capacity. Keadby also enjoys simplified complete operator training simulator (OTS) The OTS team's first task was to mark up on-line configuration. solution comprising virtualised DCS control plant piping and instrumentation diagrams Invensys also successfully delivered processors, interfaces to third-party virtual (P&IDs) in order to clarify the required a model-based OTS system, DCS controllers and a feature-rich training scope and topology of the processing sequence enhancements, process environment. This solution provides the model. Once the model had been interlock diagnostics/overrides, an on-line full power of rigorous dynamic simulation constructed, this was followed by model heat balance reconciled performance and control system emulation for process acceptance testing to demonstrate the package via the automated rigorous engineers, plant engineers, operators validity of the resulting process simulation. performance monitoring product that and managers to improve plant design, The DCS and OTS teams joined together is part of the ROMeo suite and alarm check out controls, train operators and performance analysis via the third-party for the integration and testing phase. The improve plant performance. It also offers a PAS PlantState suite. modern alternative to dated, fragmented, DCS controls and third-party gas turbine empirical and hard-to-use products with controls (GE-Mark-Vie) were loaded and The project has satisfied all of the technical objectives and we now have which many engineering firms and plants I/O cross-references between these and a supportable system with the capacity currently struggle. the process model were built and verified. we need to proceed with a number of Plant simulation greatly assisted the Invensys also demonstrated an extensive control improvements which were being software migration process and allowed us track record for supporting the Foxboro held-up by the limitations of the previous to catch a number of software integration I/A series distributed control system, a system" said Hugh Ferguson. "Not only was issues before the system was accepted the migration completed with minimal key component of the enterprise control for installation on site. Without it, the plant impact on routine plant operations, it system and were able to offer a number would not have returned to service as has been possible to retain much of the of products to further enhancement the smoothly as it did and would certainly look and feel of the previous system but system including sequential function charts have required much more commissioning at the same time making improvements for DCS sequences and the ROMeo online time. If a simulator is used for software to consistency, operability and system performance suite for plant performance configurability. Furthermore, we now have acceptance testing, it is necessary to metrics. a number of new tools in our toolbox. For avoid integrating DCS code too early example not only did the simulator play an since (just like on the real plant), control This is an advanced, unified modelling important role in the migration project, is it environment delivering online optimisation updates often take time, particularly if they now proving particularly beneficial both for applications to help users obtain peak require additional (virtual) plant run-ups to staff training and as a rigorous test-bed for performance from their operating units. The install or test. control and process changes." suite offers process optimisation across an Virtual plant commissioning was The extensive migration upgrade at the entire enterprise with online modelling and implemented on a plant area-by-area Keadby Power Station resulted in several equation-based optimisation capabilities basis; balance of plant 1, balance of gains for the plant and SSE acknowledged providing more accurate, current operating plant 2, gas turbines, waste heat recovery Invensys for providing a standardised and information to better manage changing boilers and the . Virtual plant successful migration solution. market pressures, product values, energy commissioning on the simulator mimicked Contact Jaco Markwat, Invensys, costs and equipment performance. that which would have occurred on the Tel 011 607-8100, The migration approach showed that real plant and included plant pre-start, [email protected]

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