Project overview
We reviewed the options available for long-term support for three industrial gas turbine control systems located offshore in the inhospitable North Sea. The installation was one of the client’s headline facilities and the obsolescence of control systems was already identified as a risk for the long-term safety operation of the asset.
Our experience in non-OEM based gas turbine support and control systems retrofits enabled us to provide a complete integration service package. We brought together legacy turbines with new control systems, based on our bespoke IP, to provide a single procurement interface for a complete solution.
The challenge
The existing turbine control systems were original Rustronic and the detailed survey identified a solution to supply pre-assembled panels to be installed within the existing steelwork. The design sought to replace the existing Rustronic Mk II, HMI, BN3300 VMS and CCC 3+ hardware within the turbine control module enclosure and use the existing field cabling and wiring. This represented a significant saving in resources, materials and time.
Scope of work
We supported the client through site visits, offshore surveys and multinational meetings to develop a suitable solution within the timeframe and budget constraints.
The project scope included the replacement turbine control systems for the three SGT-200 gas turbines complete with a new fuel control train and compressor load control.
We provided gas turbine control solutions based on Siemens and Rockwell platforms, including standard control and safety upgrades for most aero or industrial GT engine types for mechanical and electrical drive applications.
The selected control solution provided was based on a Rockwell ControlLogix PLC system with a replacement HMI for integration into the existing platform DSCS systems architecture. The turbine control system also included the upgrade of the vibration monitoring system to utilise the Bently Nevada BN3500 with an upgrade of the CCC load and anti-surge control system to CCC 3++. A separate HIMA safety controller provided independent overspeed and machinery protection logic.
We worked closely with the client’s site team to accommodate a challenging installation programme, which resulted in the client opting to have the control packages pre-installed in new panels to reduce the offshore workload, simplifying storage and increasing the available installation windows.
The entire retrofit control systems were manufactured at our facilities in Norfolk.
The local HMI workstation provided control and diagnostics of the gas turbine with application software based on the graphics from the original control system. New screens and functionality were added to support the new functions, diagnostics and live monitoring of the BN 3500.
The HMI displayed the typical information as shown on the image.
Turbine package overview
- Turbine control
- Fuel system overview
- Main lube oil system
- GG lube oil system
- EGT thermocouples
- Sequence flow charts
- Cooling systems
- Governor overview
- Vibration monitoring
- MCC
- Surge control
- Alarms
- Real time and historical trending
Conclusion
The non-OEM turbine control package was based on our proven control algorithms running on standard PLC platforms, This has been honed with years of experience in retrofitting a range of engine types.
We supplied the client with:
- A complete integrated gas turbine control system including governor, EGT and sequencer with independent safety controller and vibration monitoring system
- Compressor load control system
- Fuel system upgrade kit for the gas turbine including intelligent gas fuel metering valve, shut-off valves and spool pieces
- Desktop remote access PC to integrate with and monitor all three gas turbines
- Engineering laptop with pre-installed engineering and support software
- Supply of comprehensive project documentation pack including quality plan, project plan, electrical schematics and FDS, BOM, GA, O&M, MRB etc.
- Complete assembly and testing of the integrated system at our premises in Norwich, UK
- Offshore installation and commissioning services
- Spare parts for commissioning and 2-year operation
The client has now formed a larger formal arrangement with us for further projects on their expanding ageing assets onshore and offshore.
