Thesis (M. Eng.)--Carleton University, 1995. / Includes bibliographical references. Also available in electronic format on the Internet.

Made available in DSpace on 2014-06-11T19:22:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-09-19Bitstream added on 2014-06-13T18:49:34Z : No. of bitstreams: 1 guerreromaldonado_e_me_ilha.pdf: 1070580 bytes, checksum: 467d9e6e4447a40879b63f4afed6ca4d (MD5) / Atualmente, a tecnologia da compensação que utiliza controladores eletrônicos para a flexibilização dos sistemas (controladores FACTS) provê recursos aos sistemas de transmissão de energia elétrica que permitem o controle dinâmico do fluxo de energia desde a geração até o consumo. Para que se torne factível o uso de FACTS no sistema de distribuição, faz-se necessária a implantação de um sistema de comunicação para o monitoramento em tempo real de toda grade de energia até o centro de controle. Com o controle dinâmico e o monitoramento dos diversos equipamentos distribuídos no sistema de energia, tem-se o conceito das Redes Inteligentes ou Smart Grids (SG). Através deste conceito, as tecnologias de informação e comunicação (TIC) terão um papel relevante em todas as fases do ciclo de geração, transporte, comercialização e consumo. A realidade da SG deve transformar o sistema elétrico. Nesse sentido, este trabalho propõe, através da análise teórica, uma solução para comunicação entre o compensador série controlado a tiristores para rede de distribuição (D-TCSC), localizado em uma rede de distribuição na zona rural, com o centro de controle, localizado a centenas de quilômetros de distância. A tecnologia sugerida, de acordo com as características do estudo de caso, foi a GPRS. A sugestão foi feita analisando a relação entre a quantidade de dados a ser transmitida e o tempo de transmissão. Os resultados das análises mostram que a utilização de a tecnologia GPRS, para efetuar a comunicação em aplicações de teleproteção, é factível. Entretanto, para alcançar melhor desempenho, sugere-se a utilização das tecnologias 3G e 4G, quando estas oferecerem cobertura de sinal para ambientes remotos / Nowadays, FACTS controllers are very important for allowing dynamic control of power flow from generation to consumption. The use of FACTS controllers in distribution systems has become more feasible with the implementation of communication system for real-time monitoring. The dynamic control and monitoring of several equipment in distributed power system has arisen the Smart Grids concept. Through this concept, the information and communication technologies (ICT) have important role in all stages of generation, transportation, marketing and consumption. The SG shall transform the electrical system. This work proposes, through theoretical analysis, the communication between a thyristorcontrolled series compensator, located in a distribution network in the countryside, with the control center, located several hundred kilometers away. The suggested technology, according to the characteristics of the study case, was the GPRS. The suggestion was based on the ratio among the distance, the amount of data to be transmitted and the transmission time. The analysis results show that the use of the GPRS-technology to provide communication in a SG is suitable

Thesis (MTech (Quality))--Cape Peninsula University of Technology, 2010. / Eskom is embarking on a project that addresses security of supply initiatives, which are live work, high-voltage underground cabling, strategic spares, network planning and design, change management, technical training and contractor development, to strengthen the security and the reliability of the supply chain. This research investigates the causes of poor quality workmanship by the contractors during the construction of network infrastructure. The impact that the contractors have on the network's performance, and the reliability of the supply chain are very important to evaluate, as it is one of the key performance indicators measured for business performance. The quality of workmanship and the best practices that the contractors provide during the construction phase have an impact on the performance of the network, which is why this research will focus on the development of the contractors to improve the quality of workmanship. In the past few years Eskom Distribution Division has experienced numerous electrical faults in the networks, resulting in a loss of power to the customers and loss of revenue to the organisation. Contractor development is one of the methods used to build positive and mutually benefiting relationships between the buyer and the supplier. The method used in this research was through looking at the current practices, from the selection of contractor to development and maintaining of the supplier database. The objectives of the proposed research are to Improve the quality of workmanship of the contractors, Improve the project lead times during construction and investigate contractor development initiatives.

In this thesis, we present several novel theoretical results in complex networks, most of which benefit from extensions of existing methods of analysis in electrical engineering. These results not only contribute to a better characterisation of the topology and structure of complex networks, but also provide a new way to study complex systems by modelling them as a flow network to determine how nodes nonlocally interact as a function of the adjacent physical laws. We also contribute towards a better understanding of how frequency synchronisation (FS) in coupled phase oscillator networks comes about by revealing the fundamental mechanisms and determinant conditions for nodes to become FS. Moreover, we design a scheme to control explosive synchronisation. Equipped with the theoretical knowledge obtained from the study of phase oscillator networks, we reveal the mechanism behind the onset of FS in realistic models of power grids and the causes behind frequency collapse. Furthermore, we put forward advanced control techniques and novel prediction methods to prevent blackouts from happening in those models. These results might help engineers to construct a stable, economic and efficient smart power grid in the near future. The breakthroughs in this thesis build up a bridge which, on the one hand, promotes the progress of the research in the fields of complex networks and synchronization by borrowing methods from electrical engineering and extending them to the treatment of complex networks, and on the other hand, aids engineers to efficiently solve some specific problems in smart grids based on the knowledge of approaches coming from the area of complex systems. Therefore, this thesis bridges the gap between engineering and physics by identifying, explaining and extending interdisciplinary approaches from these two disciplines to better understand models and networks considered within these fields.

D.Ing. / In this study we consider the application of Reed-Solomon codes on two distinct channels. The first channel is the packet erasure channel, where packets are either received errorfree,or packets are lost. The second channel is the power line channel where additive Gaussian noise,, impulsive noise and narrowband noise are encountered In this thesis we focus on M-FSK modulation for the power line channel. For the packet erasure channel,we develop two new erasures-only decoders .The distinction between the two decoders is that the one is optimized for burst erasure correction, while the second decoder is optimized for random erasure correction.It is found that for single burst erasures, or bursterasures contained within n - k elements (where n is the code length and k is the number of information elements to be encoded), the best performance is obtained with the burst erasure decoder. When used in conjunction with a modified interleaver found in the literature, the developed random erasure decoder yields the best all-round performance. The main contribution to the power line channel is the development of a combined demodulation and decoding strategy to detect narrowband interference When standard Reed-Solomon codes operate in a channel where narrowband interference is present, undetected errors result. With the proposed decoding strategy it is found that wideband noise (a generalization of impulsive noise) affects the performance more negatively than narrowband noise for M-FSK modulation. .

M.Ing. / Line commutated thyristor converters are proven to be natural line harmonic currentgenerating sources regardless of their operating modes. The quality of harmonic current components induced back to the lines is commonly described to be similar under both states of operation. This however does not seem to be quite obvious as far as the aggregate harmonic current contribution to the phase inputs per operating region of thyristor converters. It becomes thus important to examine the degree of association between thyristor converter operating states and the magnitude of current harmonic pollution induced back to the input lines to subsequently establish the most current harmonic polluting region of operation. For the purpose of this study, the Nyquist-Shannon theorem, best known as the sampling theorem, whereby the converter output signal or waveform is sampled by the switching function to reconstruct the input waveform, is numerically applied in conjunction with the MatLab/Simulink 7.0 which enables the simulation of the two-quadrant operation of direct current variable speed drive (DC VSD) and that of high voltage direct current link (HVDC) converter station operation, as well as physical measurements on the twoquadrant operation of the DC VSD (Saftronics DC2L) with the aid of the digital scope meter (DSO)1200 series. However, numerical analysis based on the sampling theorem, practical measurements obtained and the MatLab/Simulink simulations indicate that the converter operating states cause a randomly distributed harmonic current generation trend in the input lines as the firing angle is increased and the most harmonic current contribution cannot be attributed to a specific region of the controlled converter firing angle.

No description available.

The rigorous load-flow analysis of Distribution Networks requires the modeling of mutual coupling, multiphase possibilities and unbalanced loading. The Ladder Load-Flow Method meets these requirements, but is limited to radial systems. The Switch Compensation Method presented here, extends the Ladder Load-Flow Method to solve Distribution Networks. A network analysis program has been developed using the Electric Power Research Distribution Engineering Workstation (DEWorkstation). The program uses the pointers provided by the DEWorkstation to represent the connectivity of the system. The use of these pointers increases the speed of execution while naturally handling the sparsity of the system. The user is also provided with "on line" attribute and topological data maintenance. The extension technique is based on Thevenin's Theorem. This approach allows the accurate determination of the equivalent impedance for networks which contain series and shunt elements. The equivalent impedance can be changed during the iterative solution process. This allows the algorithm to simulate the operation of control devices which significantly alter the impedance of the network. A transformer model for the forward and reverse trace of the Ladder Method is also presented. / Ph. D.

No description available.

The classic problem of achieving high Q, band pass, inductorless filters has been traditionally attacked by applying active RC networks. This approach suffers from the faults of poor economy, lack of stability of performance with time and temperature, and high network performance sensitivity to component changes. The problem is reviewed from the aspect of applying techniques other than operational amplifier RC filters. The techniques presented are those of N-Path (switching) and Digital Filters. The underlying theory of both methods is explored and a design example for each of the techniques is presented. These designs are then compared on the basis of design complexity, parts cost (count) and ease of fabrication. On the basis of the comparison of designs, it is shown which technique is more economical for the problem under discussion.