Subsea oil production technology has developed markedly I recent years. Operator are actively Seeking to increase yields from fields by smart production management, use of long step-out from on shore facilities of floating platforms and in general to manage subsea production as an integral part of the overall process control system. Several key technologies are required to enable this level of advancement open topside systems using common communication protocols, high speed robust modems transmitting on either copper and fibre media, new power transmission systems suitable for ultra-long umbilical and subsea network. In this work, subsea network topologies are describe and analysed strategies for communication accros the umbilical to opebn topside systems are discussed, with emphasis being given ti the application of fibre based systems for date rich applications. The use of available industrial standard as a basis for subsea control systems architechtures are examined and optimal solution sought. The advantage of close integration between subsea and topsides process historians and optimiser are discussed. The use of commercial software components and object-based standard(such as OPC) within the subsea control system are noted as a means of ensuring reliable and secure inter- and intra-net based interfaces. Finally, power transmission systems are discussed and the options for the use of alternating and direct currant power analysed in terms of the step-out distance and field loading.


Major changes in technology occur through serendipitous invention of a radical new concept or through ordered development work aimed at satisfied a well defined market need. In the case of the former, a product may be quickly realised but market up take will follow almost immediately. In term of subsea technology, development of the first subsea electro-hydraulic controls sytems (SPCS) was radical in concept. Painstakingly targeted development of that concept has lead us to the current level of technology deployed today.

In comparison, chemical process technology has been subjected to many more radical changes in the time taken to complete the development cycle of SPCS. These advances include process intensification, process optimization and ultimately on-line time operational analyses of overall asset performance. The goal of such development have been to reduce the operating expense, OPEX and capital expense, CAPEX and minimize spend on OPEX been most aggressively pursued in the petroleum business and especially in the are of hydrocarbon extraction and subsea extraction in particular.

Capital and operating expense associated with the development and operation of subsea hydrocarbon production assets have been the subject of constant review by their operators. Optimisation has focused on maximising return on net assets used whilst ensuring the longevity of these assets at minimum OPEX. The balance to be struck between constraints result in an ongoing need to control process parameters to a level beyond that considered the norm, avoidance of process need to control process parameters to a level beyond that considered the norm, avoidance of process excursations that cause damage to equipment or reservoir structure is essential. Historically such optimisation and process control has concentrated almost solely on topside equipment and process. It is only in recent years that subsea process have been considered and by and large these consideration have focused on the simpler aspects of process control choke positioning, chemical injection for the amelioration of corrosion, hydrate, scale and wax formation and basic flow assurance based on simple metering and state po

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