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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
261

Disaggregation of residential electric loads using smart metered data

Holcomb, Chris L. 15 July 2011 (has links)
The ability of typical utility meters and advanced meters including sub-circuit metering to disaggregate residential electric loads and determine what appliances a homeowner is using at a given time in investigated. The basics of residential electricity systems, instrumentation options, and characteristics of selected residential loads are presented. This information informs a discussion on present and future disaggregation algorithms. The conclusions highlight the importance of reactive power and current harmonics in determining power consumed and identifying modern electrical devices, and raise concerns related to the ability of typical 15 minute interval utility smart meters to disaggregate loads. / text
262

Implementation of a multi-agent based power market simulator

劉紅進, Liu, Hongjin. January 2001 (has links)
published_or_final_version / Electrical and Electronic Engineering / Master / Master of Philosophy
263

Agent based simulation of energy trends : a study of smart metering technology diffusion in the electricity market via a complexity science approach

Zhang, Tao January 2011 (has links)
No description available.
264

State regulation of railroad and electric rates in Arizona to 1925; a study of the origin and activities of the Arizona corporation commission

Griffith, Victor Sydney January 1931 (has links)
No description available.
265

Long-term supply mix planning of power systems accounting for greenhouse gas emissions

Momen, Mustafa. January 2008 (has links)
Recent scientific findings have generated considerable concern about the adverse effect of greenhouse gas (GHG) emissions on the world's climate in general and global warming in particular. In Canada and many other countries, this concern has led to the adoption of legal and political steps with the aim of curbing GHG emissions. The first part of this thesis describes the steps taken by Canada in this regard. / Such steps provide a strong incentive to Canadian power systems to incorporate reduction of GHG emissions in their planning process. Thus, in the second part of the thesis, a long-term supply mix planning model is developed. Since significant decrease in GHG emissions is unlikely to occur without removal of highly polluting power plants, this model allows for decommissioning these power plants. / Finally, the supply mix planning model is applied to evaluate the strategy of joint planning (as opposed to separate planning) of the power systems of Quebec and Ontario. Results obtained from the model leads to the conclusion that joint planning is preferable from the point of view of overall social and financial cost.
266

Aktyviosios ir reaktyviosios galių režimų valdymas restruktūrizuotoje elektros energetikos sistemoje / Active and reactive power control in restructured electrical energy system

Šulga, Dalius 25 July 2005 (has links)
The main objective of the Thesis is to work out the methodology aimed to develop a closely integrated electricity network model to be used for real time calculations, and afterwards, based on this methodology, to develop a model of a closely integrated electricity network, which would be applicable in real time calculations of active and reactive power.
267

Consumer response to power conservation program.

Ramnarain, Veer Nishaan. January 2009 (has links)
In January 2008 the South African power grid operated by Eskom became severely constrained because electricity demand exceeded supply. Following the immediate measure of load shedding, Eskom implemented a medium term strategy of Power Conservation to encourage consumers to reduce their power usage so that overall demand could be managed. Despite the extensive campaigns the 10% electricity savings target was not met in 2008. The aim of this study was to review the experiences of other countries that had successfully implemented Power Conservation Programmes and to research the different approaches that were taken in other countries to encourage behaviour change. A survey and quantitative analysis was undertaken on a sample of electricity consumers within the eThekwini Municipality Central Region to gauge the response of consumers to the power conservation campaigns conducted within the municipality. The analysis was done to determine how the response had varied among the various groups by taking into account demographic factors like age, gender and income level. The population of the sample frame was estimated at 15 000 customers. Two hundred and eighty responses were received and analysed. A salient finding of the study was that the majority of respondents were aware of the reasons for power conservation and the campaigns undertaken, but that there was a preference for Government to lead the initiative and subsidise the required savings measures. A second important finding was that different demographic groups implemented different savings measures, for different reasons and preferred different strategies to encourage savings. The main recommendations made were that Government should lead the savings drive, with customised campaigns for different demographic groups. The campaigns should place greater emphasis on the financial benefits to be gained. It was necessary for new and different savings measures to be communicated. Further, the was a need for Government to introduce legislation to enforce electricity savings. / Thesis (MBA)-University of KwaZulu-Natal, Westville, 2009.
268

Advanced classification and identification of plugged-in electric loads

Du, Liang 13 January 2014 (has links)
The total electricity consumption of plugged-in electric loads (PELs) currently accounts for more usage than any other single end-use service in residential and commercial buildings. Compared with other categories of electric loads, PELs possess significant potential to be efficiently controlled and managed in buildings. Therefore, accurate and reliable PEL identification methods that are used to collect identity and performance information are desired for many purposes. However, few existing electric load identification methods are designed for PELs to handle unique challenges such as the diversity within each type of PEL and similarity between different types of PELs equipped by similar front-end power supply units. The objective of this dissertation is to develop non-intrusive, accurate, robust, and applicable PEL identification algorithms utilizing voltage and current measurements. Based on the literature review of almost all existing features that describe electric loads and five types of existing methods for electric load identification, a two-level framework for PELs classification and identification is proposed. First, the supervised self-organizing map (SSOM) is adopted to classify a large number of PELs of different models and brands into several groups by their inherent similarities. Therefore, PELs with similar front-end power supply units or characteristics fall into the same group. The partitioned groups are verified by their power supply unit topology. That is, different groups should have different topologies. This dissertation proposes a novel combination of the SSOM framework and the Bayesian framework. Such a hybrid identifier can provide the probability of an unknown PEL belonging to a specific type of load. Within each classified group by the SSOM, both static and dynamic methods are proposed to distinguish PELs with similar characteristics. Static methods extract steady-state features from the voltage and current waveforms to train different computational intelligence algorithms such as the SSOM itself and the support vector machine (SVM). An unknown PEL is then presented to the trained algorithm for identification. In contrast to static methods, dynamic methods take into consideration the dynamics of long-term (minutes instead of milliseconds) waveforms of PELs and extract elements such as spikes, oscillations, steady-state operations, as well as similarly repeated patterns.
269

The impact of supplier quality management on Eskom's Eastern Region power network operations.

Asmal, Riaz. January 2011 (has links)
South Africa’s national power utility, Eskom, procures products and services from a multitude of suppliers for its operations. Annually, Eskom’s Eastern Region spends approximately two billion rand on the procurement of products and services for its power network operations. Considering the expenditure, what is the effect of supplier quality management on Eskom’s operations? The aim of this study was to determine the impact of supplier quality management on Eskom’s Eastern Region’s power network operations. A multi methods approach was used for this study which included quantitative data and phenomenological interviews. For the past two financial years, Eskom’s Eastern Region procured R2.7billion worth of products and services from 187 suppliers for its operations. A probability sample of 82 suppliers was drawn from this population. The sample was composed of 58% electrical construction companies, 20% product manufacturers, 17% consulting engineers and 5% electrical hardware distributors. Data was collected using an email questionnaire developed by the researcher. Structured phenomenological interviews on supplier quality management were conducted with 41 employees of Eskom’s Field Services Department. These employees were chosen as they are directly accountable for managing network operations and are end-users of suppliers’ products and services. Significantly, the statistical analysis and the outcome of the phenomenological interviews revealed points of convergence and divergence between the stated positions of the suppliers and the actual experience of Eskom’s employees on quality of products and services. By combining the quantitative and qualitative dimensions of this study, the analysis illustrated the existence of cavernous gaps between suppliers and actual experience of Eskom employees on quality management areas such as suppliers’ commitment to product and service quality, focus on customer satisfaction, effective quality control and network operations. Several elements of the suppliers’ quality management programmes don’t meet Eskom’s expectations. The results of the study can benefit both suppliers and Eskom in identifying aspects of quality management that are negatively impacting operations and recommends areas of improvement. / Thesis (MBA)-University of KwaZulu-Natal, Durban, 2011.
270

The potential contribution of small hydroelectric generation to meeting electrical demand on Vancouver Island.

Schuett, Matthew T. 31 October 2008 (has links)
This work focuses on the electrical contribution small hydro generation can make to meeting Vancouver Island's electrical demand, today, and as further development proceeds. A hydrologic assessment of Vancouver Island was undertaken for the period of 1999 to 2005. Eight regional areas were identified that exhibited temporally similar specific discharge runoff patterns, termed flow area curves (FACs). A small hydro generation MATLab model was developed and the FACs used as input to represent available generation flow. The model was used to calculate temporally accurate generation values from 175 small hydro facilities under four development scenarios for the seven year period. Generation results from each scenario were compared to electrical demand on Vancouver Island during that time period to determine the contribution provided by small hydro facilities. Results demonstrated that small hydro facilities are unable to offer dependable capacity, but are capable of meeting a portion of Vancouver Island's electrical demand.

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