| Summary: | Pri.or to 1990, and the advent of deregulation in the UK, the Electricity Supply Industry (ESI) was a state-owned, vertically integrated monopoly. For the first time the way was opened for the introduction of competitiveness into the many and varied aspects ofthe market. This brought with it diversity and additional requirements for customer and engineering services. This new business-driven, customer-orientated environment led to the re~assessment of the utility's customer communication systems. In order to take full advantage of this new environment, an integrated communications and information systems infrastructure is required. This thesis addresses the design and development of an efficient and reliable communications system for the collection and distribution of data within the ESI. Although the communications architecture proposed focuses on meeting the requirements of a specific Regional Electricity Company, SWEB, it is generic and hence may be used in any electric utility. This architecture, based on an open systems approach, provides bearer services to existing and emerging engineering and business applications. The open system aspect permits the deferred design of system components, thereby providing maximum system flexibility and simplicity. An overview ofthe operational systems in the ESI as they existed in 1997 is given. This review considers the power engineering and distribution networks, metering and tariffs, together with SWEB's specific IT and data communication systems. There then follows a review ofthe business and technical environments in the industry, in terms ofthe potential benefits of value-added services and the emerging applications, together with a brief analysis of the post-privatisation growth ofthe telecommunications industry in the UK. A review was carried out on the media used for different communication services involving Power Line Carrier technology (PLC), Telephony, Fibre Optic Cable (FOC), Twisted Pair and Coaxial cable. These media are examined as to their suitability for data communications for the electric utility industry. Various modulation techniques including AM, FM and Spread Spectrum systems were investigated with respect to their transmission characteristics, and a comparison made ofthe modulation techniques used in PLC systems. The 1990s saw considerable interest in utility communications resulting in many trials being carried out throughout the world. A number ofthese are reviewed in this thesis in support of the proposed architecture. The cardinal factor in the design and development of any modern communication system is the compliance with internationally agreed standards and recommendations. The Open Systems Interconnection model is introduced. together with the standards, protocols and profiles particularly relevant to utility communications. The Utility Communications Architecture (UCA) profile, developed by the Electric Power Research Institute (EPRI) is also introduced. The programme ofwork outlined in this thesis was driven by two objectives. The first of these was the aim of utilising the considerable copper infrastructure in the ESI distribution systems for communication purposes. The second was to investigate the feasibility of the provision ofvalue-added services. The generic architecture presented here, based on powerline carrier and other media technology, clearly satisfies the first ofthe above objectives. However PLC inherently lacks the bandwidth for some ofthe value-added services considered, and this may lead slow data transfer rates for certain applications such as downloading large text, image and audio files from internet websites.The second objective was pragmatically modified to address the problems of Remote Metre Reading. To this end a protocol is proposed which requires a minimum data rate transfer thereby conserving network bandwidth.
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