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Within today's privatised electricity industry, post-fault disturbance analysis is becoming an increasingly challenging prospect for protection engineers. Not only must they be proficient at operating a diverse range of data gathering tools but they must also be able to spend the time necessary to interpret the large volumes of data generated by modern network monitoring devices. Although a degree of automated assistance is provided by existing intelligent decision support tools, it remains for the protection engineer to manually collate and interpret the output of each system in order to compile a comprehensive understanding of each disturbance. As detailed in this thesis, the requirement for manual intervention has been eliminated through the development of the Protection Engineering Diagnostic Agents (PEDA) decision support architecture capable of automating all aspects of post-fault disturbance analysis. An essential component within this architecture is an alarm processor developed specifically to assist protection engineers with the early stages of post-fault disturbance analysis. The novel reasoning methodology employed emulates a protection engineer's approach to alarm analysis, providing automatic identification of transmission system disturbances and events. PEDA achieves fully automated post-fault disturbance analysis through the novel use of Multi-Agent Systems (MAS) to integrate the alarm processor with other automated systems for fault record retrieval, fault record interpretation and protection validation. As will be described in the thesis, achieving systems integration using MAS provides for levels of architecture flexibility and extensibility not previously realised within existing integrated decision support architectures. The PEDA architecture was developed following a comprehensive eleven stage methodology created as part of the reported research to assist with the specification of MAS for decision support within the power industry. Each stage of the PEDA specification process is detailed together with its implementation. Finally, the implemented architecture has been shown to offer automated retrieval, interpretation, collation and archiving of disturbance information within five minutes of a disturbance occurring. The beneficiaries of this near real-time provision of disturbance information need not be limited to protection engineers.

The increased use of the Internet and web technology has introduced various web based applications and strategies for businesses such as the e-Business developments. The move to an information-based economy where information has become an important value added resource, has also helped to accelerate the e-Business adoption process. In this research, e-Business is regarded as more than just technology; it encompasses a concept, ideas, and strategies to integrate individual information systems in order to create knowledge management systems for an organisation's internal processes and their activities in the supply chain. The impact and strategic significance of e-Business has been discussed widely for industries such as finance, advertising, entertainment, and travel. However, its impact on large traditional, hierarchical, monopolistic enterprises that were formerly owned by government, such as electricity, gas, and postal companies, has only had limited analysis. In order to investigate the effects of e-Business on these types of enterprises, this research has chosen the electricity industry as its focus. This research discusses the background, models, and theories of e-Business in general. Subsequently, it looks at the current structure and dynamics of the electricity industry, in particular deregulation, and analyses how industry players have adapted to the new deregulated environment. This research then investigates e-Business opportunities within the electricity industry by exploring current e-Business perceptions, approaches, barriers to implementation, and strategies of the companies operating in both the deregulated and regulated electricity environment. Using a mainly qualitative method, this research presents the findings from five UK case companies (representing electricity companies operating in a deregulated environment) and one case company from Malaysia (representing a traditional and monopolistic electricity company operating in a regulated environment). This research then provides a framework for current e-Business implementation in the electricity industry and its future potentials based on the UK and Malaysian experiences. It also provides a point of reference for other companies planning to implement e-Business as one of the ways to compete successfully in the deregulated environment.

This thesis examines the effect of geomagnetic disturbances on the UK power system. This is done in two parts. The characteristics of the ground magnetic field across the UK during frequent disturbances are determined. Using the UK Sub-Auroral Magnetometer Network, data are used from substorms during 2000-2003 encompassing solar maximum. Results are compared to a study at higher latitudes during solar minimum and using different substorm detection methods. Similar results are seen, for example mean magnetic variation increases with latitude even in the mid-latitude range and values are approximately double during storm time substorms than those in non- storm time. The results also demonstrate that the difference in substorm detection techniques produces different results when examining characteristics with respect to substorm onset time. Geomagnetic disturbances are a hazard to ground based technology and the second part of this thesis involves the development of a model that computes Geomagnetically Induced Currents in the National Grid arising from geomagnetic disturbances. The model is used with test uniform electric fields to ascertain the effect of the configuration of a power network representative of the UK National I Grid. The model is then combined with magnetometer data and a resistivity model of the UK (constructed by the British Geological Survey) to compute an equivalent electric field during geomagnetic disturbances known to produce GIC at four monitored sites in the National Grid. Modelled GIC are compared to measured data, results identify particular nodes such as In~~t:-Jl..Rueens as areas in the network at risk should a large geomagnetic storm occur. They also show that the simplifications of the modelled grid cause the GIC amplitudes to be larger than recorded. Suggestions of how future work could improve the model are given.

Feedback and goal-setting interventions were used in two separate studies to reduce residential electricity use in households in Northern Ireland. In Study 1 feedback was provided via a pre-payment keypad electricity meter, and the goal commitment was to reduce electricity use by 20%. Electricity use during a one-month intervention was compared to that during the same period in the previous year. The ten households who received feedback reduced their use by a mean 17.13% (p< .0 I, r = 0.69), and the nine households who signed a goal-setting commitment reduced their use by a mean 7.12% (p < .05, r = .067). Study 2 used wireless energy monitors to provide feedback, in combination with a 20% goal-setting commitment for all participants, but also used alternating orders of presentation of intervention and baseline to explore the longer-term effect of feedback on conservation performance. Group 1 received five months of feedback followed by five months of baseline, Group 2 underwent five months of baseline followed by five months of intervention, and Group 3 experienced alternating two-month periods of intervention and baseline over ten months, using a reversal design. Group 1 saved a mean 9.54% of electricity during the intervention, but Group 2 increased their use by a mean 14.24%. Group 2's increase in electricity use is explained in terms of a potential 'compensation effect', whereby lower level users increase use when given feedback. Group 3 showed a pattern of cumulative reductions over successive interventions, with a mean reduction in electricity use of 33% from the first to the third intervention period. Participants in Group 3 did not show a return to baseline levels of electricity use when the intervention was removed; this was interpreted as supportive of conceptions of feedback as a learning tool, with potential to provide long lasting conservation effects.

The thesis is essentially concerned with some theoretical aspects of the economic and stability studies of power systems with great penetration levels of renewable energy. In part I, firstly, the process of incorporation of VSC MTDC model in ACIDC state estimation is described in detail. The proposed approach simultaneously upgrades the estimated values of the state variables, for a unified solution in a single reference frame. The effectiveness of the proposed ACIMTDC state estimation algorithm and the bad data identification process is demonstrated and validated in modified IEEE test system. Secondly, the optimal power flow (OPF) of a meshed ACIDC power transmission network with Voltage Source Converter based Multi-terminal DC (VSC-MTDC) networks is presented in the thesis. The OPF problem is formulated to minimize the transmission loss of the whole ACIDC network with two different VSC control strategies considered. In addition, Grid Code compliance of wind farms is also embedded in the OPF formulation. The results of the proposed OPF demonstrate that the power losses of the meshed ACIDC power systems can be greatly reduced. In part Il, a novel emergency damping control (EDC) is proposed to suppress inter-area oscillations occurred as anticipated low-probability cases in power system operations. The proposed EDC combines the event-driven and response-based control strategy. It is tested and evaluated in a standard power system and a real large-scale power system in China to compute the optimal location, amount and applying time of generator decreasing and load shedding in order to suppress inter-area oscillations.

Electricity supply security has received increased attention in both academic literature and relevant policy debate. There is, however, limited discussion about the role of the key actors of the electricity sector and their engagement with security concepts. This research explores the security performance of individual fuel and technology options, focusing on the perceptions of energy policy makers and electricity incumbents towards these options and their main drivers. Energy policy makers and electricity industry experts from incumbent companies in Greece and Poland were interviewed using Multi Criteria Mapping (MCM) to rank options against specific criteria based on quantitative and qualitative input. In addition a new index was developed to quantify electricity supply security as a measure of supply independence. Established energy diversity indices (Shannon- Wiener and Herfindahl- Hirschman) were also calculated. Recent trends in diversity and independence were contrasted with results from the interviews. It was found that low carbon energy options, wind energy, nuclear, hydro and biomass were considered the most secure options by interviewees in Greece. In Poland the first options included the dominant solid fuels, and renewable energy options such as wind energy, hydro power and biomass. However, in Greece, wind was followed by other low-carbon energy options: hydropower, biomass and nuclear. Interviewees did not use analytical frameworks when appraising options and were reluctant to suggest specific criteria for the MCM design. However, when using criteria their training background influenced their choices significantly. The significant differences between the two countries were that: Polish interviewees valued affordability higher than Greek interviewees; diversity was more important to Greek experts; and independence was more important to Polish experts. The findings in Poland suggesting that the status quo was not challenged are consistent with the expectation that the policy preferences serve incumbent interests. It was recommended that the .potential benefits of analytical methods for evaluating energy supply security should be explored further. Finally, fuel mix influencing decisions should be informed by experts of varied backgrounds in order to include all (often mutually contrasting) perspectives. d

Rural electrification has centred mainly on the extension of grid supplies. However, grid extensions are not always viable for some communities due to either their smals size or location. Developments in renewable energy systems have lead to increased of renewable-diesel hybrid systems to provide power to small remote communities where grid connections are not viable. The selection of the rural hybrid energy system is influenced by the load, availability of renewable resources and system operating costs.

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