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Integrated full electric propulsion systems are being introduced across both civil and military marine sectors. Standard power system analysis packages cover electrical and electromagnetic components but have limited models of mechanical subsystems and their controllers. Hence, electromechanical system interactions between the prime movers, power network, and driven loads are poorly understood. This paper reviews available models of the propulsion drive system components: the power converter, motor, propeller, and ship. Due to the wide range of time constants in the system, reduced-order models of the power converter are required. A new model using state-averaged models of the inverter and a hybrid model of the rectifier is developed to give an effective solution combining accuracy with speed of simulation and an appropriate interface to the electrical network model. Simulation results for a typical ship maneuver are presented. Index Terms--Electromechanical interactions, marine, propulsion, rectifier models.

There is a growing need for accurate and time efficient modelling of electrical distribution networks within the aerospace industry, for which power electronic converters are an integral part. Simplifying converter models is necessary to improve simulation execution times, however many existing techniques do not necessarily give accurate results for all types of system level studies. This paper describes an alternative modelling approach to these, which provides accurate results and reduced simulation times for studies of electrical fault analyses.

Online diagnostics and online condition monitoring are important functions within the operation and maintenance of a power plant. When there is knowledge of the relationships between the raw data and the underlying phenomena within the plant item, typical intelligent system-based interpretation algorithms can be implemented. Increasingly, health data is captured without any underlying knowledge concerning the link between the data and their relationship to physical and electrical phenomena within the plant item. This leads to the requirement for dynamic and learning condition monitoring systems that are able to determine the expected and normal plant behavior over time. This paper describes how multi-agent system technology can be used as the underpinning platform for such condition monitoring systems. This is demonstrated through a prototype multi-agent anomaly detection system applied to a 2.5-MW diesel engine driven alternator system. Index Terms--Cooperative systems, decision support systems, generators, intelligent systems, monitoring, multi-agent systems.

UK government's schemes like levy exemptions, capital grants and renewable obligation certificates designed to achieve the renewable energy targets by 2010 are discussed. Suggestions are offered to ensure that small-scale and community based profit oriented renewable energy schemes too are focused towards achieving these targets.

Initial steps for various proposed decomposition mechanisms of 5-nitro-2,4-dihydro-3H-1,2,4-triazol-3-one (NTO) were investigated theoretically to determine the energies of different reaction intermediates. Harmonic vibrational frequencies were calculated to characterize the species of the stationary points. On the basis of the energetics of the different schemes, the calculations showed that C-NO2 bond homolysis is the most probable initial step for unimolecular decomposition of NTO.

There is now considerable pressure on electric utilities to operate their systems in the most efficient manner possible and to provide increased quality of service to customers. This pressure, coupled with the decreasing availability of reserve margins dictates that there is a requirement for comprehensive system operation support through, among other things, the provision of quality information relating to the behaviour of the primary and secondary systems. This paper will show how the data available within modern substation control and management systems can be exploited in a cost-effective manner, through the implementation of advanced substation functions in an open systems environment. Certain functions which are presently carried out at the control centre could be distributed (or partially distributed) to the substation. These functions may provide the utility staff with quality information, which can in turn be used to satisfy the objectives of increasing quality and security of supply, in addition to optimising the utility's information, maintenance and asset management functions.

This paper discusses model based reasoning applied to protection system performance analysis. Appropriate modelling and reasoning methodologies are indicated, and their advantages considered. The necessity of incorporating protection system performance analysis within a decision support system (DSS), designed for utility protection engineers, is presented. Alarm processing and fault diagnosis are demonstrated as further requirements of the DSS for protection engineers, within which knowledge based reasoning and model based reasoning are combined to provide the overall functionality required.

Significant improvements have been taking place in the power and extent of the monitoring and control systems employed by electrical power utilities, with the result that strategic decisions are having to be made concerning the use of the increased data now available. The evolutionary changes being made to power systems are introducing increased expectations of the performance of system management and control. However, more effective system control can only be exercised if the increased volume of data is matched by an increased capacity to interpret system conditions from the control room. The decision support system described in this paper makes use of expert system techniques in order to provide intelligent reasoning based on the incoming alarm data. Both the readily available benefits, and the advance towards the next generation of power systems which this type of system will afford shall be presented along with a description of the decision support system.

This paper describes novel designs for magneto-optic and electro-optic crystal sensors providing potentially separate and combined current and voltage measurement. The results of testing programmes are presented and details of the work associated with field trials given.

This paper presents two expert system developments which are each concerned with utilizing, to the best effect, the increasing volume of SCADA (Supervisory Control And Data Acquisition) system data available to power system control staff. The systems presented, APEX and RESPONDD, are aimed at the two related fields of alarm processing, and fault diagnosis respectively. The areas of commonality between these systems are discussed as well as details specific to each separate system, including a case study of practical operation of each.

Expert evaluation models with fuzzy theory are necessary to understand the uncertainties related to the forced outage rates (FOR) of generating units. The calculation of fuzzy FOR helps understand the conditions of operation and maintenance of the units more realistically. Constant failure and repair rates are inadequate models for complex problems like power generation. The evaluation of correct distribution is difficult for complex systems.

This paper discusses a novel approach to model integration applied within electrical power engineering. A model integration methodology, exploiting the novel approach developed and underpinned by agent technology, is proposed. Index Terms--Artificial intelligence, intelligent agents, power systems modeling, simulation.