The objective of the proposed research is to analyze automated residential energy management technology using primary energy source utilization. A residential energy management system (REMS) is an amalgamation of hardware and software that performs residential energy usage monitoring, planning, and control. Primary energy source utilization quantifies power system levels impacts on power generation cost, fuel utilization, and environmental air pollution; based on power system generating constraints and electric load. Automated residential energy management technology performance is quantified through a physically-based REMS simulation. This simulation includes individual appliance operation and accounts for consumer behavior by stochastically varying appliance usage and repeating multiple simulation iterations for each simulated scenario. The effect of the automated REMS under varying levels of control will be considered. Aggregate REMS power system impacts are quantified using primary energy source utilization. This analysis uses a probabilistic economic dispatch algorithm. The economic dispatch algorithm quantifies: fuel usage and subsequent environmental air pollution (EAP) generated; based on power system generating constraints and electric load (no transmission constraints are considered). The analysis will comprehensively explore multiple residential energy management options to achieve demand response. The physically-based REMS simulation will consider the following control options: programmable thermostat, direct load control, smart appliance scheduling, and smart appliance scheduling with a stationary battery. The ability to compare multiple automated residential energy management technology options on an equal basis will guide utility technology investment strategies.

Thesis (M. En.)--Miami University, Institute of Environmental Sciences, 2004. / Title from first page of PDF document. Includes bibliographical references (p. 31).

Power distribution network (PDN) design was a non-existent entity during the early days of microprocessors due to the low frequency of operation. Once the switching frequencies of the microprocessors started moving towards and beyond MHz regions, the parasitic inductance of the PCB tracks and planes started playing an important role in determining the maximum voltage on a PDN. Voltage regulator module (VRM) sup-plies only the DC power for microprocessors. When the MOSFETs inside a processor switches, it consumes currents during transition time. If this current is not provided, the voltage on the supply rails can go below the specifications of the processor. For lower MHz processors few ceramic-capacitors known as ‘decoupling capacitors’ were connected between power and ground to provide this transient current demand. When the processor frequency increased beyond MHz, the number of capacitors also increased from few numbers to hundreds of them. Nowadays, the PDN is said to be comprising all components from VRM till the die location. It includes VRM, bulk capacitors, PCB power planes, capacitor mounting pads and vias, mount for the electronic package, package capacitors, die mount and internal die capacitance. So, the PDN has evolved into a very complex system over the years. A PDN should provide three distinct roles; 1) provide transient current required by the processor 2) act as a stable reference voltage for processor 3) filter out the noise currents injected by the processor. The first two are required for the correct operation of the processor. Third one is a requirement from analog or other sensitive circuits connected to the same PDN. If the noise exits the printed circuit board (PCB), it can result in conducted and radiated EMI, which can in turn result in failure of a product in EMC testing. Every PDN design starts with the calculation of a target impedance which is given as the ratio of maximum allowed ripple voltage to the maximum transient current required by the processor. The transient current is usually taken as half the average input current. The definition of target impedance assumes that the PDN is flat over the entire frequency of operation, which is true only for a resistive network. This is seldom true for a practical PDN, since it contains inductances and capacitances. Because of this, a practical PDN has an uneven impedance versus frequency envelope. Whenever two capacitors with different self resonant frequencies are connected in parallel, their equivalent impedance produces a pole between the self resonant frequencies known as antiresonance peaks. Because of this, a PDN will have phase angles associated with them. Also, these antiresonance peaks are energy reservoirs which will be excited during the normal operation of a processor by the varying currents. The transient current of a microprocessor is modeled as a gamma function, but for practical cases it can be approximated as triangular waveforms during the transition time which is normally 10% of the time period. Depending upon the micro-operations running inside the processor, the peak value of this waveform varies. This is filtered by the on-chip capacitors, package inductance and package capacitors. Due to power gating, clock gating, IO operations, matrix multiplications and magnetic memory readings the waveforms at the board will be like pulse type, and their widths are determined by these operations. In literatures, these two types of waveforms are used for PDN analysis, depending upon at which point the study is conducted. Chapter 1 introduces the need for PDN design and the main roles of a PDN. The issue of antiresonance is introduced from a PDN perspective. Different types of capacitors used on a PDN are discussed with their strengths and limitations. The general nature of the switching noise injected by a microprocessor is also discussed. This chapter discusses the thesis contributions, and the existing work related to the field. Chapter 2 introduces a new method to calculate the target impedance (Zt ) by including the phase angles of a PDN which is based on a maximum voltage calculation. This new Zt equals to conventional Zt for symmetrical triangular switching current waveforms. The value of new Zt is less than the conventional Zt for trapezoidal excitation patterns. By adding the resonance effects into this, a maximum voltage value is obtained in this chapter. The new method includes the maximum voltage produced on a PDN when multiple antiresonance peaks are present. Example simulations are provided for triangular and pulse type excitations. A measured input current wave-form for PIC16F677 microcontroller driving eight IO ports is provided to prove the assumption of pulse type waveforms. For triangular excitation waveform, the maximum voltage predicted based on the expression was ¡0.6153 V, and the simulated maximum voltage was found to be at ¡0.5412 V which is less than the predicted value. But the predicted value based on Zt method was 1.9845 V. This shows that the conventional as well as the new target impedance method leads to over estimating the maximum voltage in certain cases. This is because most of the harmonics are falling on the minimum impedance values on a PDN. If the PDN envelope is changed by temperature and component tolerances, the maximum voltage can vary. So the best option is to design with the target impedance method. When pulse current excitation was studied for a particular PDN, the maximum voltage produced was -139.39 mV. The target impedance method produced a value of -100.24 mV. The maximum voltage predicted by the equation was -237 mV. So this shows that some times the conventional target impedance method leads to under estimating the PDN voltage. From the studies, it is shown that the time domain analysis is as important as frequency domain analysis. Another important observation is that the antiresonance peaks on a PDN should be damped both in number and peak value. Chapter 3 studies the antiresonance peak suppression methods for general cases. As discussed earlier, the antiresonance peaks are produced when two capacitors with different self resonant frequencies are connected in parallel. This chapter studies the effect of magnetic coupling between the mounting loops of two capacitors in parallel. The mounting loop area contribute to the parasitic inductance of a capacitor, and it is the major contributing factor to it. Other contributing factors are equivalent series inductance (ESL) and plane spreading inductance. The ESL depends on the size and on how the internal plates of the capacitors are formed. The spreading inductance is the inductance contributed by the parts of the planes connecting the capacitor connector vias to the die connections or to other capacitor vias. If the power and ground planes are closer, the spreading inductance is lower. On one/two layer boards dedicated power/ground planes are absent. So the spreading inductance is replaced by PCB track inductances. The inductance contributed by the mounted area of the capacitor is known as mounting inductance. On one/two layer boards dedicated power/ground planes are absent. So the spreading inductance is replaced by PCB track inductances. The dependencies of various circuit parameters on antiresonance peak are studied using circuit theory. A general condition for damping the antiresonance is formulated. The antiresonance peak reduces with Q factor. The conventional critical condition for antiresonance peak damping needs modification when magnetic coupling is present between the mounting loops of two parallel unequal value capacitors. By varying the connection geometry it is possible to obtain negative and positive coupling coefficients. The connection geometries to obtain these two are shown. An example is shown for positive and negative coupling coefficient cases with simulation and experimental results. For the example discussed, RC Æ 32 - for k Æ Å0.6 and RC Æ 64 - for k Æ ¡0.6, where RC is the critical damping value and k is the magnetic coupling coefficient between the two mounting loops. The reason for this is that, the antiresonance peak impedance value is higher for negative coupling coefficient case than that for positive coupling coefficient case. Above the self resonant frequencies of both the capacitors, the equivalent impedance of the parallel capacitors become inductive. This case is studied with two equal value capacitors in parallel. It is shown that the equivalent inductance is lower for negative coupling coefficient case as compared to positive coupling coefficient case. An example is provided with simulation and experimental results. In the experimental results, parasitic inductance is observed to be 2.6 times lower for negative coupling coefficient case than that for positive coupling coefficient case. When equal value capacitors are connected in parallel, it is advantageous to use a negative coupling geometry due to this. Chapter 4 introduces a new method to damp the antiresonance peak using a magnet-ically coupled resistive loop. Reducing the Q factor is an option to suppress the peak. In this new method, the Q factor reduction is achieved by introducing losses by mag-netically coupling a resistive loop. The proposed circuit is analyzed with circuit-theory, and governing equations are obtained. The optimum value of resistance for achieving maximum damping is obtained through analysis. Simulation and experimental results are shown to validate the theory. From the experimental results approximately 247 times reduction in antiresonance peak is observed with the proposed method. Effectiveness of the new method is limited by the magnetic coupling coefficient between the two mounting loops of capacitors. The method can be further improved if the coupling coefficient can be increased at the antiresonance frequency. Chapter 5 focuses on the third objective of a PDN, that is to reduce the noise injected by the microprocessor. A new method is proposed to reduce the conducted noise from a microprocessor with switched super capacitors. The conventional switched capacitor filters are based on the concept that the flying capacitor switching at high frequency looks like a resistor at low frequency. So for using at audio frequencies the flying capacitors were switching at MHz frequencies. In this chapter the opposite of this scenario is studied; the flying capacitors are the energy storage elements of a switched capacitor converter and they switch at lower frequencies as compared to the noise frequencies. Two basic circuits (1:1 voltage conversion ratio) providing noise isolation were discussed. They have distinct steady state input current waveforms and are explained with PSPICE simulations. The inrush current through switches are capable of destroying them in a practical implementation. A practical solution was proposed using PMOS-PNP pair. The self introduced switching noise of the converter is lower when switching frequency is low and turn ON-OFF time is higher. If power metal oxide semiconductor field effect transistor (MOSFET)s are used, the turn ON and turn OFF are slow. The switching frequency can be lowered based on the voltage drop power loss. The governing equations were formulated and simulated. It is found that the switching frequency can be lowered by increasing the capacitance value without affecting the voltage drop and power loss. From the equations, it is found that the design parameters have a cyclic dependency. Noise can short through the parasitic capacitance of the switches. Two circuits were proposed to improve the noise isolation: 1) T switch 2) ¦ switch. Of these, the ¦ switch has the higher measured transfer impedance. Experimental results showed a noise reduction of (40-20) dB for the conducted frequency range of 150 kHz - 30 MHz with the proposed 1:1 switched capacitor converter. One possible improvement of this method is to combine the noise isolation with an existing switched capacitor converter (SCC) topology. The discussed example had a switching frequency of 700 Hz, and it is shown that this can isolate the switching noise in kHz and MHz regions. In a PDN there are antiresonance peaks in kHz regions. If the proposed circuit is kept close to a microprocessor, it can reduce the excitation currents of these low frequency antiresonance peaks. Chapter 6 concludes the thesis by stating the major contributions and applications of the concepts introduced in the thesis. This chapter also discusses the future scope of these concepts.

In power utilities the subject reliability is a permanent worry. In this new context, some solutions have been developed and researched to an alternative to improve the performance on service restoration when there are consumers without power supply. Among possible solutions the installation of remotely-controlled switches represents a solution that has been adopted by many companies due its cost benefit. The allocation of these devices is essential to assess the different criterions and characteristics, so the use of multi-criteria decision making to evaluate these characteristics and especially to allow the measurement of expert s opinion in power distribution systems is essential. Therefore, the objective of this work is to propose a new methodology for the allocation of these devices in electric distribution systems based on AHP - Analytic Hierarchy Process decision making for validation of the best locations to install theses device. The contribution and innovation of this work consist in adding to the allocation methodology a validation of expert opinion, discarding those that present a very low consistency and thus making the final answer more exact and in accordance with the proposal, through a variation of the AHP methodology. / Em empresas de sistemas de potência a confiabilidade é uma preocupação constante. Nesse novo contexto, algumas soluções têm sido desenvolvidas e pesquisadas como alternativa para melhorar sua performance em propiciar um retorno do fornecimento de energia elétrica aos seus consumidores quando estes estão desenergizados. Dentre as soluções possíveis, a instalação de chaves telecomandadas tem representado uma solução cada vez mais adotada por várias empresas de energia devido ao seu custo benefício. Na alocação desses equipamentos é essencial considerar diferentes critérios e características, desta maneira o uso de uma metodologia de decisão multicriterial é necessário e especialmente para permitir a mensuração da opinião de especialistas do setor de sistemas de distribuição. Então, o objetivo desse trabalho é propor uma nova metodologia de alocação desses dispositivos em sistemas de distribuição de energia baseado na metodologia de tomada de decisão AHP - Analytic Hierarchy Process para validação das melhores localizações para instalar esses equipamentos. A grande contribuição e inovação desse trabalho consiste apresentar uma metodologia de alocação desses equipamentos, uma validação da opinião dos especialistas, descartando aquelas que apresentam uma baixa consistência e desta forma tornando a resposta final mais exata e de acordo com o proposto, através de uma variação da metodologia AHP.

A silicon interposer platform with microfluidic cooling is proposed for high-performance computing systems. The key components and technologies for the proposed platform, including electrical and fluidic microbumps, microfluidic vias and heat sinks, and simultaneous flip-chip bonding of the electrical and fluidic microbumps, are developed and demonstrated. Fine-pitch electrical microbumps of 25 µm diameter and 50 µm pitch, fluidic vias of 100 µm diameter, and annular-shaped fluidic microbumps of 150 µm inner diameter and 210 µm outer diameter were fabricated and bonded. Electrical and fluidic tests were conducted to verify the bonding results. Moreover, the thermal and signaling benefits of the proposed platform were evaluated based on thermal measurements and simulations, and signaling simulations. Compared to the conventional air cooling, significant reductions in system temperature and thermal coupling are achieved with the proposed platform. Moreover, the signaling performance is improved due to the reduced temperature, especially for long interconnects on the silicon interposer. A numerical power distribution network (PDN) simulator is developed based on distributed circuit models for on-die power/ground grids, package- and board- level power/ground planes, and the finite difference method. The simulator enables power supply noise simulation, including IR-drop and simultaneous switching noise, for a full chip with multiple blocks of different power, decoupling capacitor, and power/ground pad densities. The distributed circuit model is further extended to include TSVs to enable simulations for 3D PDN. The integration of package- and board- level power/ground planes enables co-simulation of die-package-board PDN and exploration of new PDN configurations.

Dissertation (PhD)--University of Stellenbosch, 2000. / ENGLISH ABSTRACT: The purpose of this dissertation is to provide methods for designing and managing low voltage residential feeders. These methods can be applied to the problem of planning residential networks under uncertainty while ensuring least life-cycle costs. By analysing collected load data from various communities in South Africa, a new probabilistic model for representing the load uncertainty of residential consumers was derived. This model uses the beta probability distribution to describe individual consumer loads over a period of time. Methods for combining the loads in linear combinations were used to derive a new probabilistic voltage regulation calculation procedure. This new method is different from previously developed voltage calculation methods in that it can be used to estimate the probable voltage performance of a feeder over a period of time. A simplification of the method is proposed which allows it to be implemented in any commercial spreadsheet program. The new probabilistic load model was also applied to the problem of calculating resistive losses in residential low voltage feeders. A new probabilistic method was formulated and this method can be used to estimate the probable range of resistive loss in a feeder for a period of time. This method is simple enough to implement in a commercial spreadsheet program. Probabilistic information about network and load parameter uncertainty is seldom available and these uncertainties are best modelled using fuzzy numbers. The probabilistic calculation methods cannot represent these uncertainties and only after applying a fuzzy-probabilistic approach can both types of uncertainties be used. This is a significant enhancement to the current methods and ensures that the uncertainty about the calculated results is realistically represented. The specification of load parameters for the methods was significantly simplified following a regression analysis of collected load data from South African communities. By specifying the distribution of the consumption of individual consumers in a community, the other load parameters can be estimated using a set of fitted linear regression equations. This greatly reduces the burden of specifying the load parameters and makes it possible for the proposed calculation methods to be applied to the design of new feeders in practice. The distribution of the consumption of individual consumers can be specified using the average and the standard deviation of the consumptions of individual consumers. Accurate estimates of these parameters can be obtained from sales information and can be used to manage existing networks effectively. Using the sales information with the proposed methods enables more cost-effective upgrades of existing feeders low voltage feeders. The identification of potential problems in existing low voltage networks is also possible if the layout of the feeders in a community is known. The use of the proposed methods is illustrated in step-by-step fashion. Typical input parameters are used and all the required calculations with intermediate results are presented. / AFRIKAANSE OPSOMMING: Die doel van hierdie proefskrif is die daarstelling van residensiële laagspanningsnetwerk ontwerp- en bestuursmetodes. Hierdie metodes kan toegepas word vir die beplanning van residensiële laagspanningsnetwerke waar onsekerheid bestaan oor toekomstige kragverbruik en die spesifikasie van die netwerkparameters. Lasdata, wat versamel is in verskeie Suid Afrikaanse gemeenskappe, is geanaliseer en 'n nuwe probabilistiese modellering van die onsekerheid oor die kragverbruik van residensiële verbruikers is ontwikkel. Gebruik is gemaak van die beta waarskynlikheidsdightheidsfunksie om die tydsgebonde kragverbruik van die verbruikers voor te stel. 'n Nuwe probabilistiese spanningsvalberekeningsmetode is ontwikkel en die metode maak gebruik van liniêre kombinasies van die lasstrome van die verbruikers. Die verskil tussen hierdie metode en bestaande metodes is dat dit die tydsgebonde waarskynlikheid van die spanningsregulasie van 'n kabel kan bereken. 'n Vereenvoudiging van die metode is ook verkry en dit kan in enige kommersiële sigblad geïmplementeer word. Die probabilistiese lasstroommodel is ook gebruik om 'n nuwe probabilistiese energieverliesberekeningsmetode te ontwikkel. Hierdie metode kan gebruik word om die tydsgebonde waarskynlikhede van 'n reeks van moontlike energieverlieswaardes te bereken. Die metode is eenvoudig genoeg om in enige kommersiële sigblad te implementeer. Onsekerheid oor die spesifikasie van die parameters van die nuwe metodes asook die netwerkparameters kan nie met probabilistiese metodes voorgestel word nie, aangesien inligting oor die waarskynlikhede van parameters selde beskikbaar is. Hierdie onsekerhede kan beter voorgestel word deur die gebruik van sogenaamde "fuzzy"-metodes. Die voorgestelde probabilistiese metodes is aangepas om hierdie tipe onsekerhede ook in ag te neem. "Fuzzy-probabilistic" metodes is gebruik vir dié aanpassings en word beskou as 'n noemenswaardige verbetering van die metodes. Die verbeterde metodes verkaf meer realistiese voorstellings van die onsekerheid oor berekende resultate. 'n Statisitiese analise van Suid Afrikaanse lasdata het 'n vereenvoudiging van die spesifisering van die parameters van die nuwe metodes tot gevolg gehad. Die waarskynlikheidsverspreiding van die energieverbruik van huishoudelike verbruikers kan gebruik word om akkurate skattings van die ander parameters te verkry. Hierdie vereenvoudiging het tot gevolg dat die nuwe metodes vir praktiese netwerkontwerp gebruik kan word. Die waarskynlikheidsverpreiding van die energieverbruik van verbuikers is beskikbaar in die vorm van energieverkope en kan gebruik word vir die effektiewe bestuur en opgradering van bestaande netwerke. As die uitleg van die bestaande netwerke in 'n gemeenskap beskikbaar is, kan die inligting wat bevat is in die energieverkope gebruik word om probleme in bestaande netwerke te identifiseer. Al die voorgestelde metodes is stap vir stap uiteengesit met voorbeelde van al die berekeninge met tipiese waardes.

Thesis (PhD)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: Accurate load models are required for the computation of load flows in MV distribution networks. Modem microprocessors in recent times enable researchers to sample and log domestic loads. The findings show that they are stochastic in nature and are best described by a beta probability distribution. . In rural areas two different load types may be present. Such loads are domestic and pump loads, the latter may be modelled as constant P - Q loads. An analytical tool for computing voltage regulation on MV distribution networks for rural areas feeding the mentioned loads is therefore required. The statistical evaluation of the consumer voltages requires a description of load currents at the time of the system maximum demand. To obtain overall consumer voltages at any specified risk for the two types of the loads, the principle of superposition is adopted. The present work deals with conventional 22kV three-phase distribution (te:. - te:.) connected networks as used by ESKOM, South Africa. As the result of the connected load, MV networks can experience poor voltage regulation. To solve the problem of voltage regulation, voltage regulators are employed. The voltage regulators considered are step-voltage regulators, capacitors and USE (Universal Semiconductor Electrification) devices. USE devices can compensate for the voltage drops of up to 35% along the MV distribution network, thus the criteria for the application of the USE devices is also investigated. The load currents are treated as signals when assessing the cost of distribution system over a period of time due to power losses. The individual load current signal is modelled by its mean and standard deviation. The analytical work for developing general expressions of the total real and total imaginary components of branch voltage drops and line power losses in single and three-phase networks without branches are presented. To deal with beta-distributed currents on MV distribution networks, new scaling factors are evaluated at each node. These new scaling factors are derived from the distribution transformer turns ratio and the deterministic component of the statistically distributed load currents treated as constant real power loads. In the case of an individual load current signal, the transformation ratio is evaluated from the distribution transformer turns ratio and the average value of the· signal treated as constant real power load. The evaluation of the consumer voltage percentile values can be accurately evaluated up to 35% voltage drop. This is possible by the application of the expanded Taylor series, using the first three terms. The coefficients of these three terms were obtained using a search engine imbedded in the probabilistic load flow. The general expressions for evaluating the overall consumer voltages due to statistical and non-statistical loads currents are also given. These non-statistical currents may be due to constant P - Q loads, line capacitance and the modeling of voltage regulators. The Newton-Raphson algorithm is applied to perform a deterministic load flow on singlephase networks. A backward and forward sweep algorithm is applied to perform a deterministic load flow on single and three-phase systems. A new procedure for modelling step-voltage regulators in three-phase (te:. - te:.) connected networks is outlined. Specifying a transformation ratio of 1.1 and 1.15 respectively, identifies the open-delta or closed-delta configuration for three-phase networks. The algorithms and the developed general expressions for single and three-phase networks without branches are presented in this work. A new algorithm is developed to enable the developed general expressions to be applied to practical MV distribution networks. The algorithms were tested for their accuracy by comparing the analytical results with Monte Carlo simulation and they compared well. An illustrative example to show the application of the present work on a practical MY distribution networks is presented. A criterion for the application of the USE devices is outlined. It is anticipated that, the work presented in this thesis will be invaluable to those involved in the design of MY distribution systems in developing countries. / AFRIKAANSE OPSOMMING: Akkurate lasrnodelle word benodig vir drywingsvloei analises in MV distribusiestelsels. As gevolg van nuwe digitale verwerkers is dit deesdae moontlik om huishoudelike laste te monitor. Die lasdata dui daarop dat laste stochasties is en kan met behulp van die Beta verdeling beskryf word. In landelike gebiede is daar twee tipes laste. Hulle is eendersyds huishoudelike laste en andersyds pomp-tipe laste wat as konstante P-Q laste beskou kan word. Dit is dus belangrik om toepaslike analitiese metodes te gebruik om die spanningsvalle by hierdie laste te bereken met inagname van die las-tipes. By die statistiese berekening van die verbruiker se spanning moet 'n statistiese model van die lasstroom verskaf word op die tydstip van maksimum aanvraag. Daarna moet die prinsiep van superposissie gebruik word om die spannings by verskeie nodes by 'n gespesifiseerde vertrouensinterval te bepaal. Hierdie proefskrif is gebaseer op konvensionele 22kV, drie fase distribusie (delta na delta) netwerke, soos deur Eskom, Suid Afrika gebruik. Hierdie stelsels ondervind dikwels nadelige spanningsvlakke en spanningsreëlaars word derhalwe aangewend. Hierdie reëlaars is gewoonlik van tap-tipe of daar kan ook gebruik gemaak word van kapasitore en ook elektroniese reëlaars soos die USE tipe toestelle. Laasgenoemde kan op LV vir spanningsvalle tot 35% kompenseer. In hierdie werk word die werkdrywing verliese in die geleiers bereken met behulp 'n seinmodel van die lasstrome. Die individuele lasstrome word by wyse van gemiddeldes en variasies beskryf. Om die algemene algoritmes vir die berekening van die reële en imaginêre spanningsvalle, asook die verliese in enkelfase en driefase stelsels daar te stel word aanvanklik gebruik gemaak van stelsels sonder vertakkings. Om die statistiese lasbeskrywing op die laagspanningskant na die MV vlak oor te dra word van nuwe skaalfaktore gebruik gemaak. Hierdie faktore word bereken op die basis van die transformator se verhouding en die deterministiese komponent van die statistiese verspreide lasstrome, as konstante reële drywingslaste beskou. Met die ontwikkelde metode kan die verbruiker se spanning by 'n gegewe vertrouensinterval akkuraat bereken word vir spanningsvalle tot 35%. Dit word moontlik gemaak deur die Taylor-reeks tot drie terme toe te pas. Daar moet egter gebruik gemaak word van toepaslike koëffisiënte wat bepaal word deur 'n geprogrammeerde soektog. 'n Algemene stel vergelykings om die spanning by enige verbruiker te bereken, ongeag die topologie van die netwerk, word ook gegee. Die Newton-Raphson metode word aangewend om die deterministiese drywingsvloei op enkelfase stelsels te bereken. A truwaartse-voorwaartse metode is gebruik om die drywingsvloei te bepaal vir driefase stelsels. 'n Nuwe prosedure is ontwikkel vir die modellering van die spanningsreëlaars in driefase, delta-delta netwerke. Deur gebruik te maak van 'n transformatorverhouding van 1.1 of 1.15 kan die oop-delta of toe-delta netwerke voorgestel word. 'n Nuwe algoritme is ontwikkelom multi-vertakkings in 'n netwerk te hanteer. Al die prosedures is deeglik met behulp van Monte Carlo simulasies getoets en die resultate is heel bevredigend. Om die metodes te illustreer word 'n gevallestudie ingesluit waar die metodes gebruik word om 'n netwerk te evalueer met en sonder die sogenaamde USE toestelle. Kriteria vir die aanwending van hierdie toerusting word voorgestel. Daar word verwag dat die werk soos in hierdie proefskrifuiteengesit is die ontwerp van MV distribusiestelsels, veral in ontwikkelende lande, heelwat sal verbeter.

published_or_final_version / abstract / Electrical and Electronic Engineering / Master / Master of Philosophy

The main purpose of this thesis was to develop a printed circuit board for Autoliv Electronics AB. This circuit board should be placed in their test equipment to support some of their camera vision systems used in cars. The main task was to combine the existing hardware into one module. To be able to achieve this, the most important factors in designing a printed circuit board was considered. A satisfying power distribution network is the most crucial one. This was accomplished by using decoupling capacitors to achieve low enough impedance for all circuits. Calculations and simulations were executed for all integrated circuits to find the correct size and numbers of capacitors. The impedance of the circuit board was tested with a network analyzer to confirm that the impedance were low enough, which was the case. System functionality was never tested completely, due to delivery problems with some external equipment.

Doctor of Philosophy / Department of Computing and Information Sciences / Scott A. DeLoach / Coalition formation is a key cooperative behavior of a system of multiple autonomous agents. When the capabilities of individual agents are not su fficient for the improvement of well-being of the individual agents or of the entire system, the agents can bene t by joining forces together in coalitions. Coalition formation is a technique for finding coalitions that are best fi tted to achieve individual or group goals. This is a computationally expensive task because often all combinations of agents have to be considered in order to find the best assignments of agents to coalitions. Previous research has therefore focused mainly on small-scale or otherwise restricted systems. In this thesis we study coalition formation in large-scale multi-agent systems. We propose an approach for coalition formation based on multi-agent simulation. This approach allows us to find coalitions in systems with thousands of agents. It also lets us modify behaviors of individual agents in order to better match a specific coalition formation application. Finally, our approach can consider both social welfare of the multi-agent system and well-being of individual self-interested agents. Power distribution systems are used to deliver electric energy from the transmission system to households. Because of the increased availability of distributed generation using renewable resources, push towards higher use of renewable energy, and increasing use of electric vehicles, the power distribution systems are undergoing signi ficant changes towards active consumers who participate in both supply and demand sides of the electricity market and the underlying power grid. In this thesis we address the ongoing change in power distribution systems by studying how the use of renewable energy can be increased with the help of coalition formation. We propose an approach that lets renewable generators, which face uncertainty in generation prediction, to form coalitions with energy stores, which on the other hand are always able to deliver the committed power. These coalitions help decrease the uncertainty of the power generation of renewable generators, consequently allowing the generators to increase their use of renewable energy while at the same time increasing their pro fits. Energy stores also bene t from participating in coalitions with renewable generators, because they receive payments from the generators for the availability of their power at speci fic time slots. We first study this problem assuming no physical constraints of the underlying power grid. Then we analyze how coalition formation of renewable generators and energy stores in a power grid with physical constraints impacts the state of the grid, and we propose agent behavior that leads to increase in use of renewable energy as well as maintains stability of the grid.