A simulation-optimization methodology was used to assess monitoring strategies for a drinking water distribution network. Multiple simulation trials of contamination events were used to create input data for an integer optimization problem. A network model, based on the Blacksburg, VA water distribution system, was used as the basis for a case study of contaminant transport under conditions of uncertainty. The model was not calibrated due to the lack of reliable field data. Optimization of monitoring plans was performed within the context event based simulation trials. This precluded the design of monitoring plans that were directly compatible with requirements of water quality regulations. However, the results of the optimization did provide information that may be of use to the broader problem of compliance monitoring. Optimal plans were assessed in comparison with several alternative plans using a separate set of simulation trials. Optimization of monitoring plans derived from simulated source node contamination events was generally effective at choosing points that provided better detection of source node contamination than alternative plans based on random sampling or judgement sampling. Optimal monitoring plans derived from simulated random node contamination events were ineffective at detecting random node contamination. The results of optimization and the separate analysis of monitoring plan performance indicated that the number of simulation trials may have been inadequate to completely describe the stochastic behavior of the system. Additionally, comparison of these results with those obtained from a previous simulation study indicate that the results of any simulation of distribution system contamination may be very sensitive to the level of contaminant loading and the size and layout of the system. / Master of Science

Power line communications (PLC) as applied to electrical power grid is known since long; however, PLC in microprocessors was recently introduced by VTVT Lab. Since power distribution network (PDN) inside a microprocessor is ubiquitous, therefore, any node inside a microprocessor can be accessed by attaching a simple communication circuit to it. The scheme is extremely attractive as it avoids the routing overhead of the data-path between an internal node and an I/O pin. A number of applications are possible for PLC in microprocessors such as on-line testing, monitoring/control of internal nodes, fault diagnosis etc. Feasibility of the PLC approach has been extensively studied by earlier researchers at VTVT. The feasibility studies investigated the frequency response of a microprocessor's PDN and looked for existence of passbands — frequency bands where signal attenuation through the PDN is small. Two different approaches were followed—the first approach employed analytical modeling of the high frequency characteristics of the PDN, while the second approach conducted measurements on Intel® microprocessors' PDN. Although, differences were observed in the results of the two approaches; both the approaches demonstrated existence of passbands, thus affirming the feasibility of the PLC scheme. This thesis presents a system level study conducted to estimate performance of the PLC scheme. Measurement results were used to model the PDN channel. The study provides useful insights for the design of microprocessor level PLC system. Specifically, the study estimates optimal pulse width required to maximize the system performance and the range of achievable data-rates. The study demonstrates that it is feasible to communicate data through a microprocessor's PDN without inducing large disturbances on the power line. The other work presented in this thesis is the design of low power receiver for microprocessor level PLC, also called data recovery block. The proposed design of data recovery block employs Correlation Detection (CD) receiver architecture. The design has been implemented in IBM 0.13 µm CMOS process and has been verified to operate reliably across Process, Voltage and Temperature variations. The design has a small foot-print of 300 µm x 160 µm and consumes 3.58 mW while operating from 1.2 V power supply. / Master of Science

Asset management and automation are acknowledged by distribution utilities as a useful strategy to improve service quality and reliability. However, the major challenge faced by decision makers in distribution utilities is how to achieve long-term return on the projects while minimising investment and operation costs. Distribution automation (DA) in terms of transformer economic operation (TEO), distribution network reconfiguration (DNR), and sectionalising switch placement (SSP) is recognised as the most effective way for distribution network operators (DNOs) to increase operation efficiency and reliability. Automated tie-switches and sectionalising switches play a fundamental role in distribution networks. A method based on the Monte Carlo simulation is discussed for transformer loss reduction, which comprises of profile generators of residential demand and a distribution network model. The ant colony optimisation (ACO) algorithm is then developed for optimal DNR and TEO to minimise network loss. An ACO algorithm based on a fuzzy multi-objective approach is proposed to solve SSP problem, which considers reliability indices and switch costs. Finally, a multi-objective ant colony optimisation (MOACO) and an artificial immune systems-ant colony optimisation (AIS-ACO) algorithm are developed to solve the reconfiguration problem, which is formulated within a multi-objective framework using the concept of Pareto optimality. The performance of the optimisation techniques has been assessed and illustrated by various case studies on three distribution networks. The obtained optimum network configurations indicate the effectiveness of the proposed methods for optimal DA.

As redes secundárias de distribuição são item de extrema importância no processo de levar a energia produzida de uma fonte até o consumidor final. Dentro de uma Empresa Concessionária de Distribuição de Energia Elétrica o setor de planejamento, juntamente com o grupo técnico, deve realizar o planejamento dos investimentos necessários nos níveis de alta, média e baixa tensão, sendo que para a baixa tensão (redes secundárias de distribuição), normalmente utilizam-se os dados históricos e a média de investimentos dos últimos anos (de três a cinco últimos anos). Em geral não são encontrados nestas Empresas os cadastramentos das redes secundárias de distribuição ou então, quando estes existem, muitas vezes não são confiáveis. Neste ponto, esta dissertação de mestrado apresentará, aplicará e discutirá os resultados de uma metodologia de geração de redes secundárias de distribuição a partir dos dados das redes primárias de distribuição (média tensão) e dos ativos da Empresa, tendo como foco os investimentos necessários para estas dentro do planejamento agregado de investimentos. O trabalho proposto visa criar condições para que as Empresas enquadradas na situação anterior possam realizar o seu planejamento de baixa tensão valendo-se da aplicação de uma metodologia capaz de gerar tais redes. Uma vez criadas, tais redes serão inseridas dentro de um software de planejamento agregado de investimentos que fornecerá o valor total das aplicações necessárias para os próximos dez anos (planejamento decenal – longo prazo). Ao final do processo, poderá ser observado que os resultados obtidos são muito próximos dos valores esperados para as redes secundárias reais e, com isto, a dissertação discutirá como a metodologia foi implementada, os detalhes da aplicação e, até mesmo, todo o processo de planejamento para três Empresas Concessionárias de Distribuição de Energia Elétrica. Já de posse dos resultados, poderá afirmar-se que o processo produziu valores de muito boa aderência e, assim, os investimentos obtidos para as redes secundárias poderão ser aceitos pelo grupo de planejamento da Empresa. Como conseqüência dos valores de investimentos obtidos para os dez anos, poderão ser observados ainda, guardadas algumas considerações especiais, os valores dos custos marginais de baixa tensão, item de grande importância no planejamento de redes de distribuição. / The low voltage distribution networks are an item of extreme importance in the process of delivering the produced energy from a plant (supply) to the final consumer. In an Electric Power Distribution Company the planning group (sector), together with the technical group, must accomplish the planning of the necessary investments in the high voltage, medium voltage and low voltage levels, and for low voltage distribution networks, usually the historical data and the average of investments of the last years are used (from three to last five years). In general the databases of low voltage networks are not found in these Companies or then, when these exist, a lot of times they are not reliable. For this, this article will show, apply and discuss the results of a methodology for generating low voltage distribution networks starting from the database of the medium voltage distribution networks and of the assets of the Company, having as focus the necessary investments for these networks in planning of investments. The proposed work wishes to create conditions so that the Companies that are in the previous situation can accomplish their planning on low voltage distribution networks using a methodology capable to generate such nets. Once created, such nets will be inserted in a software of planning of investments that will supply the total amount of investments for them for the next ten years (long period planning). In the end of the process, it will be observed that the obtained results are very close to the expected values for the real low voltage distribution networks and, with this, the article will discuss how the methodology was implemented, the details of the application and, even, the whole planning process for three Electric Power Distribution Companies. With the results, it will be affirmed that the process produces values of very good adherence and, for this, the investments obtained for low voltage distribution networks can be accepted by the planning group in the Company. As a consequence of the investments values obtained for the ten years, it will be able to be observed, kept some special considerations, the values of the marginal costs of low voltage, item of great importance in the planning of distribution networks.

As redes secundárias de distribuição são item de extrema importância no processo de levar a energia produzida de uma fonte até o consumidor final. Dentro de uma Empresa Concessionária de Distribuição de Energia Elétrica o setor de planejamento, juntamente com o grupo técnico, deve realizar o planejamento dos investimentos necessários nos níveis de alta, média e baixa tensão, sendo que para a baixa tensão (redes secundárias de distribuição), normalmente utilizam-se os dados históricos e a média de investimentos dos últimos anos (de três a cinco últimos anos). Em geral não são encontrados nestas Empresas os cadastramentos das redes secundárias de distribuição ou então, quando estes existem, muitas vezes não são confiáveis. Neste ponto, esta dissertação de mestrado apresentará, aplicará e discutirá os resultados de uma metodologia de geração de redes secundárias de distribuição a partir dos dados das redes primárias de distribuição (média tensão) e dos ativos da Empresa, tendo como foco os investimentos necessários para estas dentro do planejamento agregado de investimentos. O trabalho proposto visa criar condições para que as Empresas enquadradas na situação anterior possam realizar o seu planejamento de baixa tensão valendo-se da aplicação de uma metodologia capaz de gerar tais redes. Uma vez criadas, tais redes serão inseridas dentro de um software de planejamento agregado de investimentos que fornecerá o valor total das aplicações necessárias para os próximos dez anos (planejamento decenal – longo prazo). Ao final do processo, poderá ser observado que os resultados obtidos são muito próximos dos valores esperados para as redes secundárias reais e, com isto, a dissertação discutirá como a metodologia foi implementada, os detalhes da aplicação e, até mesmo, todo o processo de planejamento para três Empresas Concessionárias de Distribuição de Energia Elétrica. Já de posse dos resultados, poderá afirmar-se que o processo produziu valores de muito boa aderência e, assim, os investimentos obtidos para as redes secundárias poderão ser aceitos pelo grupo de planejamento da Empresa. Como conseqüência dos valores de investimentos obtidos para os dez anos, poderão ser observados ainda, guardadas algumas considerações especiais, os valores dos custos marginais de baixa tensão, item de grande importância no planejamento de redes de distribuição. / The low voltage distribution networks are an item of extreme importance in the process of delivering the produced energy from a plant (supply) to the final consumer. In an Electric Power Distribution Company the planning group (sector), together with the technical group, must accomplish the planning of the necessary investments in the high voltage, medium voltage and low voltage levels, and for low voltage distribution networks, usually the historical data and the average of investments of the last years are used (from three to last five years). In general the databases of low voltage networks are not found in these Companies or then, when these exist, a lot of times they are not reliable. For this, this article will show, apply and discuss the results of a methodology for generating low voltage distribution networks starting from the database of the medium voltage distribution networks and of the assets of the Company, having as focus the necessary investments for these networks in planning of investments. The proposed work wishes to create conditions so that the Companies that are in the previous situation can accomplish their planning on low voltage distribution networks using a methodology capable to generate such nets. Once created, such nets will be inserted in a software of planning of investments that will supply the total amount of investments for them for the next ten years (long period planning). In the end of the process, it will be observed that the obtained results are very close to the expected values for the real low voltage distribution networks and, with this, the article will discuss how the methodology was implemented, the details of the application and, even, the whole planning process for three Electric Power Distribution Companies. With the results, it will be affirmed that the process produces values of very good adherence and, for this, the investments obtained for low voltage distribution networks can be accepted by the planning group in the Company. As a consequence of the investments values obtained for the ten years, it will be able to be observed, kept some special considerations, the values of the marginal costs of low voltage, item of great importance in the planning of distribution networks.

The theme of this master‘s thesis is distribution network development and configuration in the part of Brno – Trnitá. There is expected to be investments there in the next few years. The thesis consists of two parts. For better understanding of this problem, the first theoretical part concerns with the description of electrical network (subdivision in accordance with voltage levels, conductor types, network types and other electrical network parts), solution of grid’s steady state (as a linear task and also non-linear task, elimination of the balancing node, the iterative method) and Brno distribution network characteristics. The second part concerns with distribution network development and configuration depending on anticipated load development in Trnitá. The result is proposal for transformer station construction Opuštěná fitted with three transformers of nominal output SN = 40 MVA and network configuration change required both for providing new consumption supply as well as sustaining current one.

Liberalized electricity markets, increased awareness of clean energy resources and theirdecreasing costs have resulted in large numbers of distributed power generators beinginstalled on distribution network. Installation of distributed generation has altered thepassive nature of distribution grid. A concept of Active Distribution Network is proposedwhich will enable present day infrastructure to host renewable energy resources reliably.Fault management that includes fault localization, isolation and service restoration ispart of active management of distribution networks.This thesis aims to introduce a distributed protection methodology for fault localizationand isolation. The objective is to enhance reliability of the network. Faults are identifiedbased on root mean square values of current measurements and by comparing thesevalues with preset thresholds. The method based on multi-agent concept can be usedto locate the faulty section of a distribution network and for selection of faulty phases.The nodal Bus Agent controls breakers that are associated with it. Based on indicationof fault, adjacent bus Agents communicate with each other to identify location of fault.A trip signal is then issued to corresponding Breakers in adjacent Bus Agents, isolatingthe faulty section of line. A case study was carried out to verify suitability of the proposedmethod. A meshed network model and multi-agent based protection scheme wassimulated in Simulink SimPowerSystems. Considering nature of Distribution Network,separate breakers for each phase are considered. The distribution network protectionsystem identified fault introduced in the network correctly along with interrupting thefault current.Keywords

Mathematical analyses indicated that significant possibilities exist for load shifting projects on a Large Potable Water Utility (LPWU) in South Africa. A primary concern remained, i.e. whether the load variation would have an effect on the water quality. Extensive simulation and testing were initiated in order to prove that the load shift will not affect the water quality. In South Africa, the highest standard for drinking water is the Blue Drop award. The LPWU has received this award multiple times and strives to maintain it. An investigation was launched to determine if this load shifting project would have an effect on the quality standards to which the utility holds (SANS 241 (2011)). The LPWU has over 3000 km of pipelines to supply potable water to the industrial heartland of the country as well as millions of domestic users. The LPWU network is the longest pumping network in the world and is still expanding. The investigation included a simulation of a pumping simulation package to determine how the system would react to the changes. In this simulation, the load reduction in terms of Mega litre per day (Ml/day) was established. Results were compared to the normal operating parameters of the Water Treatment Works (WTW). The mathematical analysis in this investigation concluded that an evening peak load shift of 24.5 MW is achievable. This dissertation will emphasise the necessity of a detailed investigation. The investigations and simulation will determine that the volume of water is well within the operating parameters of the WTW. Studies were done on each area of the plant. In-depth conversations with WTW personnel revealed that the reduction of the volume of water in question will not have an effect on the water quality. Further, it was established that it would be possible to use the sumps of the water treatment works to achieve the desired load shift. By using the sumps of the WTW, a load shift can be done without stopping any process in the WTW with the exception of disinfection at the Booster Pump Stations (BPS), where the balancing reservoirs were used as buffer capacity. The investigation shifted to establish whether stagnant water and a change in dosage would have an effect on the water quality in regard to the reduction and recovery load. As expected, the water never became stagnant at any moment due to the fact that only a small portion of the load was reduced. The water quality and dosage report of the water utility was used and compared to normal operations. The planned load shift had no effect on any aspects of the water quality. The project is feasible and will reach the set targets without affecting the water quality. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2015

Mathematical analyses indicated that significant possibilities exist for load shifting projects on a Large Potable Water Utility (LPWU) in South Africa. A primary concern remained, i.e. whether the load variation would have an effect on the water quality. Extensive simulation and testing were initiated in order to prove that the load shift will not affect the water quality. In South Africa, the highest standard for drinking water is the Blue Drop award. The LPWU has received this award multiple times and strives to maintain it. An investigation was launched to determine if this load shifting project would have an effect on the quality standards to which the utility holds (SANS 241 (2011)). The LPWU has over 3000 km of pipelines to supply potable water to the industrial heartland of the country as well as millions of domestic users. The LPWU network is the longest pumping network in the world and is still expanding. The investigation included a simulation of a pumping simulation package to determine how the system would react to the changes. In this simulation, the load reduction in terms of Mega litre per day (Ml/day) was established. Results were compared to the normal operating parameters of the Water Treatment Works (WTW). The mathematical analysis in this investigation concluded that an evening peak load shift of 24.5 MW is achievable. This dissertation will emphasise the necessity of a detailed investigation. The investigations and simulation will determine that the volume of water is well within the operating parameters of the WTW. Studies were done on each area of the plant. In-depth conversations with WTW personnel revealed that the reduction of the volume of water in question will not have an effect on the water quality. Further, it was established that it would be possible to use the sumps of the water treatment works to achieve the desired load shift. By using the sumps of the WTW, a load shift can be done without stopping any process in the WTW with the exception of disinfection at the Booster Pump Stations (BPS), where the balancing reservoirs were used as buffer capacity. The investigation shifted to establish whether stagnant water and a change in dosage would have an effect on the water quality in regard to the reduction and recovery load. As expected, the water never became stagnant at any moment due to the fact that only a small portion of the load was reduced. The water quality and dosage report of the water utility was used and compared to normal operations. The planned load shift had no effect on any aspects of the water quality. The project is feasible and will reach the set targets without affecting the water quality. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2015

Hyper-heuristics is a new field of optimisation which has recently emerged and is receiving growing exposure in the research community and literature. Hyper-heuristics are optimisation methods which are designed with a high level of abstraction from any one specific problem or class of problems and therefore are more generally applicable than specialised meta-heuristic and heuristic methods. Instead of being designed to solve a specific real-world problem, hyper-heuristics are designed to solve the problem of heuristic generation and selection. As such, hyper-heuristics can be thought of as methods for optimising the operations of an optimisation process which finds good solutions to a problem as a by-product. This approach has been shown to be very effective and in some cases provides improvement in search performance as well as reducing the burden associated with tailoring meta-heuristics which is often required when solving new problems. In this thesis, the hypothesis that hyper-heuristics can be competitively applied to real-world multi-objective optimisation problems such as the water distribution design problem is tested. Although many single-objective hyper-heuristics have been proposed in the literature, only a few multi-objective methods have been proposed. This thesis explores two different novel multi-objective hyper-heuristics: one designed for generating new specialised heuristics; and one designed for solving the online selection of heuristics. Firstly, the behaviour of a set of heuristics is explored to create a base understanding of different heuristic behavioural traits in order to better understand the hyper-heuristic behaviours and dynamics later in the study. Both approaches are tested on a range of benchmark optimisation problems and finally applied to real-world instances of the water distribution network design problem where the selective hyper-heuristics is demonstrated as being very effective at solving this difficult problem. Furthermore, the thesis demonstrates how heuristic selection can be improved by incorporating a greater level of information about heuristic performance, namely the historical joint performance of different heuristics, and shows that exploiting this sequencing information in heuristic selection can produce highly competitive results.