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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.
1

Information Management of Intelligent Electronic Devices

Lo, Jinqin January 2013 (has links)
The advent of cheaper, more powerful substation relays, now commonly known as Intelligent Electronic Devices (IEDs), will have a substantial impact on Powerco information systems. Their impact is two-fold; the sheer volume of information associated with modern relays will require a more capable relay management system than the one currently being used. The second effect is the amount of data that can be gathered and used for network improvement. Improper management of both types of information will lead to worse outcomes for Powerco reliability performance, and ultimately its financial performance. This report details two projects concerned with the management of IED information.The first project is concerned with a proposed upgrade of the Powerco relay management system. This involved requirements engineering, investigation of database systems and a commercial tendering process. It was found that the data schema had a large effect on efficiency and efficacy of relay management systems. The optimal solution would be to procure a proven relay management system from an established vendor, given resource constraints and proven-for-purpose data schema. The second project is focused on the deployment of automated event report collection software. The impetus of this project was the inefficiencies that arise from manual collection and processing of network event data from substation relays. These hamper the network improvement process, negatively affecting Powerco network reliability. A Cost-Benefit Analysis was performed to determine if such functionality was worth deploying across the network. It was found that automated event report collection produced operational savings from reduced technician dispatch frequency. Other benefits include greater data captured, faster fault response time, and a transformation of the existing reactive network improvement engineering process to one that is proactive. This will require additional engineering resources to be dedicated to event analysis. A deployment schedule was formulated based on historical reliability and agreed service levels. The larger implications of this report are that additional resourcing, and careful consideration of the information management processes are required to take advantage of the greater volume of data generated by IEDs.
2

PROPOSTA DE PLANO DE INSPEÇÃO PROATIVO PARA DISPOSITIVOS ELETRÔNICOS INTELIGENTES NA SEGURANÇA OPERATIVA DE SISTEMAS DE ENERGIA ELÉTRICA. / PROPOSAL FOR A PROACTIVE INSPECTION PLAN FOR INTELLIGENT ELECTRONIC SECURITY DEVICES IN SECURITY OPERATION OF ELECTRICAL ENERGY SYSTEMS.

GERUDE, Bruno Gomes 21 June 2017 (has links)
Submitted by Maria Aparecida (cidazen@gmail.com) on 2017-08-01T13:14:59Z No. of bitstreams: 1 Bruno Gomes Gerude.pdf: 3290960 bytes, checksum: 9bdd883476a85e1e8d0adcf47fa16ba2 (MD5) / Made available in DSpace on 2017-08-01T13:16:59Z (GMT). No. of bitstreams: 1 Bruno Gomes Gerude.pdf: 3290960 bytes, checksum: 9bdd883476a85e1e8d0adcf47fa16ba2 (MD5) Previous issue date: 2017-06-21 / As society's dependence on energy increases, the regulatory agencies' demands grow with the electric power concessionaires for quality and continuity. On the other hand, in particular, the Brazilian electrical system is much more complex due to the increase in other transmission lines, substations, direct current systems and the use of generation plants from different sources, which imposes on energy companies the adoption Strategies and procedures that guarantee greater reliability to these assets. The use of Intelligent Electronic Devices (IEDs) allows the operation of electric power systems to make faster and more assertive decisions, however, the maintenance and inspection strategies in these equipments are not even among the companies in the sector, and this has led to some professionals to abandon the idea of proactive inspection. In this work a broad approach is taken on the subject, from the perspective of manufacturers' manuals, Reliability Centered Maintenance theory (RCM) and under international norms and guidelines. It is presented a research with eight companies of the Brazilian electrical sector and a survey of information in two substations of the National Interconnected System, with evaluation of the performance of the installed IEDs which includes the construction of failure curves, stratification of defects by subsystems and comparison between the families of IEDs in these facilities. At the end, a plan of periodic inspection is proposed in these devices using a methodology based on multicriteria analysis to define periodicities. / À medida que a dependência de energia pela sociedade aumenta, crescem as exigências das agências reguladoras junto às concessionárias de energia elétrica por qualidade e continuidade. Por outro lado, em particular, o sistema elétrico brasileiro está muito mais complexo devido ao incremento de outras linhas de transmissão, subestações, sistemas de corrente contínua e a utilização de usinas de geração de diferentes fontes, o qual impõe às empresas de energia a adoção de estratégias e procedimentos que garantam maior confiabilidade a esses ativos. A utilização de Dispositivos Eletrônicos Inteligentes (IEDs) permite que a operação dos sistemas de energia elétrica possa tomar decisões mais rápidas e assertivas, no entanto, as estratégias de manutenções e inspeções nestes equipamentos não estão niveladas entre as empresas do setor, e isto tem levado alguns profissionais a abandonarem a ideia de inspeção proativa. Neste trabalho faz-se uma ampla abordagem sobre o tema, sob a ótica dos manuais de fabricantes, da teoria de Manutenção Centrada em Confiabilidade (RCM) e sob as normas e guias internacionais. É apresentada uma pesquisa com oito empresas do setor elétrico brasileiro e um levantamento de informações em duas subestações do Sistema Interligado Nacional, com avaliação do desempenho dos IEDs instalados a qual inclui a construção das curvas de falha, estratificação de defeitos por subsistemas e comparação entre as famílias de IEDs existentes nestas instalações. Ao final é proposto um plano de inspeção periódico nestes dispositivos utilizando uma metodologia baseada em análise multicritério para definição das periodicidades.
3

Detecting Suspicious Behavior with Low-Cost Sensors

Reed, Ahren Alexander 01 November 2011 (has links) (PDF)
A proof of concept is created that demonstrates how low-cost sensors and a simple software solution can be used to proactively detect IED placement. The main goal is to detect suspicious behavior; Specifically we derive requirements that loitering, meandering, improper location and object placement shall be detected. Current methods being used to detect Improvised Explosive Devices (IEDs) are costly in terms of equipment and risk to life, and many are retroactive; IED detection occurs long after explosives are placed. A prototype system is explored with the quality attributes of being low-cost, proactive and using simple software methods. A wireless sensor network of simple sensors may alert authorities to people in the act of placing IEDs. Previous work with Crossbow Motes showed that a network of infrared motion sensors can be used to detect loitering. In this prototype nine other sensors are reverse engineered to determine their true operating specifications. Then a prototype sensor network is developed to explore which low-cost sensors can be used to detect suspicious behavior. The results indicate that five low-cost sensors are effective in detecting suspicious behavior: infrared motion, infrared distance, light, force sensors and pressure sensors meet our requirements.
4

Fatores de sucesso dos Investimentos Externos Diretos - IEDs através de fusões e aquisições cross border / Success factors of Foreign Investment Direct - FDIs through mergers and acquisitions cross border

Romaro, Paulo 04 October 2016 (has links)
Submitted by Filipe dos Santos (fsantos@pucsp.br) on 2016-11-25T13:16:04Z No. of bitstreams: 1 Paulo Romaro.pdf: 3519262 bytes, checksum: b83fc63680a9b54602cf7fc9a0e8701d (MD5) / Made available in DSpace on 2016-11-25T13:16:04Z (GMT). No. of bitstreams: 1 Paulo Romaro.pdf: 3519262 bytes, checksum: b83fc63680a9b54602cf7fc9a0e8701d (MD5) Previous issue date: 2016-08-04 / Pontifícia Universidade Católica de São Paulo / This thesis aims to investigate the acquisitions carried out by national companies from fifteen countries abroad during the period 2002-2015 have increased the financial performance of these companies. The chosen countries seek to characterize different stages of economic development and confirmation of these different stages it has been ratified by a cluster analysis. In addition, based on extensive economic literature and management is carried out an empirical analysis of determinants of that success. The results indicate that, in fact, invested cross border national companies improve performance. Which is positively impacted when there is existence of financial resources in abundance in the market and the size of the companies. The number of fusions made by companies generate apparently results in form of an inverted U, that is, there is a congestion from a given amount of the fusions. States seem to be benefited from mergers and acquisitions cross border by domestic companies / Esta tese tem como objetivo investigar se as aquisições realizadas por empresas nacionais de quinze países no exterior durante o período de 2002 a 2015 têm aumentado o desempenho financeiro dessas empresas. Os países escolhidos procuram caracterizar estágios diferentes de desenvolvimento econômico e a confirmação destes estágios diferenciados foi ratificada por uma análise de clusters. Além disso, baseando-se em ampla literatura econômica e de gestão é realizada uma análise empírica de fatores determinantes desse sucesso. Os resultados indicam que, de fato, as investidas cross border de companhias nacionais melhoram o desempenho. Que é positivamente impactado quando há existencia de recursos financeiros em abundância no mercado e pelo tamanho das empresas. O volume de fusões realizados pelas empresas aparentemente geram resultados em forma de u invertido, ou seja, há uma congestão a partir de uma determinada quantidade de fusões. Os Estados parecem ser beneficiados com as fusões e aquisições cross border realizadas pelas empresas nacionais
5

Histological Characterization of Inter Ictal Epileptiform Discharges Generating Brain Regions using a Preclinical Model of Focal Cortical Dysplasia

Deshmukh, Abhay S 13 November 2015 (has links)
Current clinical practice of resective surgery in focal epilepsy involves electroencephalogram (EEG) brain source imaging to localize irritative brain areas from where Inter-ictal epileptiform discharges (IEDs) emerge, useful to localize the seizures-onset zones. Unfortunately, there are no previous systematic studies to characterize the pathophysiological mechanisms and abnormal cellular substrates in these irritative areas since histological data are available only from the final resective zones. To address this issue we applied a combination of EEG brain imaging described by Bae et al. (2015) using cutting-edge technology for high-density scalp EEG in rodents and histological analysis on a chronic rat model of focal cortical dysplasia. Post-mortem brain sections were stained for anatomical, functional and inflammatory biomarkers. Abnormal anatomical structures and increased expression of inflammatory biomarkers were found in the irritative regions. We conclude that IED-based brain source imaging can help to localize abnormal tissues highly prospective for epileptogenesis.
6

Virtualization of a sensor node to enable the simulation of IEC 61850-based sampled value messages

Luwaca, Emmanuel January 2014 (has links)
Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Electrical Engineering in the Faculty of Engineering at the Cape Peninsula University of Technology 2014 / The IEC 61850 standard, “Communication networks and systems in substations” was promulgated to accommodate the need for a common communication platform within substations for devices from different vendors. The IEC 61850 standard proposes a substation automation architecture that is Ethernet-based, with a “station-bus” for protection devices within the substation and a “process bus” where raw data from the voltage and current transformers are published onto the data network using a device known as a Merging Unit. To date, most of the standardization efforts were focused at the station bus level where event-triggered messages are exchanged between the substation automation devices, commonly referred to as Intelligent Electronic Devices (IEDs). These messages are known as Generic Object Oriented Substation Event messages. Equipment from vendors to accommodate the “process bus” paradigm, however is still limited at present. The Centre for Substation Automation and Energy Management Systems was established within the Electrical Engineering Department at the Cape Peninsula University of Technology with one of its objectives being the development of equipment either for simulation or real-time purposes in compliance with the IEC 61850 standard. In order to fulfil this long-term objective of the Centre, an in-depth understanding of the IEC 61850 standard is required. This document details the efforts at acquiring the requisite knowledge base in support of the educational objectives of the Centre and the research project implements a simulation of a merging unit which is compliant with the functional behavior as stipulated by the standard. This limited functional implementation (i.e. non-real-time) of the merging unit, is achieved through the development of a virtualized data acquisition node capable of synthetic generation of waveforms, encoding of the data and publishing the data in a format compliant with the IEC 61850-9-2 sampled value message structure. This functional behavior of the virtual sensor node which was implemented has been validated against the behavior of a commercial device and the sampled value message structure is validated against the standard. The temporal behavior of the proposed device is commented upon. This research project forms the basis for future real-time implementation of a merging unit.
7

Producing Pacification: The Disciplinary Technologies of Smart Bombs and National Anti-War Organizing

Culp, Andrew Curtis 08 September 2009 (has links)
No description available.
8

Investigation of the application of IEC61850 standard in distribution busbar protection schemes

Mnguni, Mkhululi Elvis Siyanda January 2013 (has links)
Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Electrical Engineering in the Faculty of Engineering at the Cape Peninsula University of Technology Supervisor: Prof. R. Tzoneva Co-supervisor: Prof. P. Petev 2013 / Busbars are the most important components in the distribution networks. Faults on the busbar are uncommon, however an occurrence of a busbar fault can lead to a major loss of power. Busbars are the areas in a substation where the levels of current are high and therefore the protective relay application is very critical. In order for the protection scheme to be successful it is important to carry out the following specifications: Selectivity, Stability, Sensitivity, and Speed. To meet all of the above requirements protection must be reliable, meaning that the protection scheme must trip when called up to do so (dependability) and it must not trip when it’s not supposed to (security). The thesis focuses on the reverse blocking busbar protection scheme with aim to improve the speed of its operation and at the same time to increase operational reliability, flexibility and stability of the protection during external and internal faults by implementation of the extended functionality provided by the IEC61850 standard-based protective IEDs. The practical implementation of the scheme by the use of IEC 61850 standard communication protocol is investigated. The research analyzes in detail the reverse blocking busbar protection scheme that is used at the moment in the power systems and it develops an improved IEC 61850 based reverse blocking busbar protection scheme for a distribution network. The proposed scheme is designed for a radial type of a distribution network and is modeled and simulated in the DigSILENT software environment for various faults on the busbar and its outgoing feeders. The results from the simulations are used further for implementation of the designed protection scheme. A laboratory test bench is build using three compliant with the IEC 61850 standard ABB IEDs 670 series, CMC 356 Omicron test injection device, PC, MOXA switch, and a DC power supplier. Two ways of the reverse blocking signals between the IEDs implementation are considered: hard wired and Ethernet communication by using IEC 61850 standard GOOSE messages. Comparative experimental study of the operational trip response speed of the two implementation shows that the performance of the protection scheme for the case of Ethernet communication is better The thesis findings and deliverables will be used for postgraduate studies of other students, research, short courses, and solution of industrial problems. Keywords: Busbar, Power system, reverse busbar blocking scheme; IEC61850; Distribution, Protection relays, IEDs, GOOSE message, laboratory test bench
9

Development of an embedded system actuator node for intergration into an IEC 61850 based substation automation application

Retonda-Modiya, John-Charly January 2012 (has links)
Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Electrical Engineering in the Faculty of Engineering at the Cape Peninsula University of Technology, 2012 / The introduction of the IEC 61850 standard in substations for communication networks and systems by the International Electrotechnical Commission (IEC) in 2003 provided the possibility for communication between devices of different manufacturers. However, the advent of this standard also brought about many challenges associated with it. The challenges introduced by this fairly recent standard of communications in Substation Automation Systems (SAS), and the need for the development of cost effective IEC 61850- compliant devices, motivated the decision of the Centre for Substation and Energy Management Systems within the Electrical Engineering Department of the Cape Peninsula University of Technology to focus on the implementation of the IEC 61850 standard using an embedded hardware platform. The development of an IEC 61850 embedded application requires substantial knowledge in multiple domains such as data networking, software modelling and development of Intelligent Electronic Devices (IEDs), protection of the electrical system, system simulation and testing methods, etc. Currently knowledge about the implementation of the IEC 61850 standard usually resides with vendors and is not in the public domain. The IEC 61850 standard allows for two groups of communication services between entities within the substation automation system. One group utilizes a client-server model accommodating services such as Reporting and Remote Switching. The second group utilizes a peer-to-peer model for Generic Substation Event (GSE) services associated with time-critical activities such as fast and reliable communication between Intelligent Electronic Devices (IEDs) used for protection of the power network. The messages associated with the GSE services are the Generic Object Oriented Substation Event (GOOSE) messages. The use of GOOSE messages for protection of the electrical system is very important in modern substations. Detailed knowledge of the structure of these messages is important in instances requiring fault diagnosis to determine the cause of mal– operation or to address interoperability concerns or when developing custom IEC 61850- compliant devices with limited functionality. A practical protection application (overcurrent) case study is presented where GOOSE messages are exchanged between a commercial IED and an IEC 61850-compliant controller based on an embedded platform. The basic data model and software development of an actuator node for a circuit breaker is proposed using an IEC 61850 communication stack on an embedded platform. The performance of the GOOSE messages is confirmed to be as per the functional behaviour specified, and per the IEC 68150 standard in terms of the temporal behaviour required. This thesis document tables the methods, software programs, hardware interfacing and system integration techniques that allow for the development and implementation of a low cost IEC 61850-compliant controller unit on an embedded systems platform for the substation automation system. The overcurrent case study distributed between a commercial IED (SIEMENS Siprotec device) and the actuator application developed on an embedded platform for this project (DK60 board) is in compliance with the IEC 61850 standard and utilizing GOOSE messaging is successfully completed both in terms of functional and temporal behaviour. This novel research work contributes not only to the academic community, but to the international Power Systems community as a whole. Keywords: IEC 61850 standard, IEDs, GOOSE message, software modelling, software development, substation automation systems, communication stack, embedded systems, actuator.

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