A eletricidade é um insumo cujo impacto nos custos dos serviços públicos municipais varia de acordo com a maneira como ela é utilizada e a forma como é adquirida da empresa fornecedora. A gestão de seu uso resulta em economia e em aprimoramento da eficiência e da qualidade na prestação dos serviços, incluindo a iluminação pública, além de mitigar impactos ambientais e desenvolver ações de orientação da sociedade sobre padrões de consumo eficientes de energia. O setor público representa parcela significativa do consumo final de eletricidade no Brasil, com tendência de aumento, mas identifica-se nas prefeituras municipais potencial de redução do consumo e aumento da eficiência energética. O objetivo deste trabalho é identificar conceitos e estabelecer diretrizes que possam servir de bases para uma política pública de gestão da energia elétrica no âmbito da administração municipal. Este documento relata o desenvolvimento de estudos teóricos e pesquisas empíricas sobre o uso eficiente da energia elétrica em serviços públicos em cidades de diferentes países e analisa os resultados da aplicação de modelos que vão sucessivamente se aprimorando na realidade de municípios da região metropolitana de São Paulo. Conclui que cabe à municipalidade um papel muito mais relevante que o de um mero consumidor institucional de eletricidade, propondo bases para uma intervenção na realidade do município. / Electricity is an input whose impact on the costs of the municipal public services varies according to the manner it is used and to the way it is obtained from the supplying company. The management of its use results in savings and in greater efficiency and quality of the delivered services - including the public lighting - besides, it softens environmental impacts and develops actions to orientate society towards energy-efficient consumption habits. The public sector has a significant share in the electricity final consumption in Brazil, trending to increase, but a room for consumption reduction and increase in energy efficiency can be seen in the municipalities. The purpose of this thesis is to identify concepts and set parameters that can be the basis of a public policy on electrical power management at the ambit of municipality. This paper reports a series of theoretical studies and empirical researches concerning the efficient use of electrical power in public services in cities of different countries and analyses the results reached from the application of models that successively work in the reality of cities from the Sao Paulo metropolitan area. It concludes that the municipality must play a role much more relevant than being a simple institutional electricity consumer, by proposing the basis for an intervention in the municipal reality.

A eletricidade é um insumo cujo impacto nos custos dos serviços públicos municipais varia de acordo com a maneira como ela é utilizada e a forma como é adquirida da empresa fornecedora. A gestão de seu uso resulta em economia e em aprimoramento da eficiência e da qualidade na prestação dos serviços, incluindo a iluminação pública, além de mitigar impactos ambientais e desenvolver ações de orientação da sociedade sobre padrões de consumo eficientes de energia. O setor público representa parcela significativa do consumo final de eletricidade no Brasil, com tendência de aumento, mas identifica-se nas prefeituras municipais potencial de redução do consumo e aumento da eficiência energética. O objetivo deste trabalho é identificar conceitos e estabelecer diretrizes que possam servir de bases para uma política pública de gestão da energia elétrica no âmbito da administração municipal. Este documento relata o desenvolvimento de estudos teóricos e pesquisas empíricas sobre o uso eficiente da energia elétrica em serviços públicos em cidades de diferentes países e analisa os resultados da aplicação de modelos que vão sucessivamente se aprimorando na realidade de municípios da região metropolitana de São Paulo. Conclui que cabe à municipalidade um papel muito mais relevante que o de um mero consumidor institucional de eletricidade, propondo bases para uma intervenção na realidade do município. / Electricity is an input whose impact on the costs of the municipal public services varies according to the manner it is used and to the way it is obtained from the supplying company. The management of its use results in savings and in greater efficiency and quality of the delivered services - including the public lighting - besides, it softens environmental impacts and develops actions to orientate society towards energy-efficient consumption habits. The public sector has a significant share in the electricity final consumption in Brazil, trending to increase, but a room for consumption reduction and increase in energy efficiency can be seen in the municipalities. The purpose of this thesis is to identify concepts and set parameters that can be the basis of a public policy on electrical power management at the ambit of municipality. This paper reports a series of theoretical studies and empirical researches concerning the efficient use of electrical power in public services in cities of different countries and analyses the results reached from the application of models that successively work in the reality of cities from the Sao Paulo metropolitan area. It concludes that the municipality must play a role much more relevant than being a simple institutional electricity consumer, by proposing the basis for an intervention in the municipal reality.

With the rapid growth of servers and applications spurred by the Internet economy, power consumption in today's data centers is reaching unsustainable limits. This has led to an imminent financial, technical and environmental crisis that is impacting the society at large. Hence, it has become critically important that power consumption be efficiently managed in these computing power-houses of today. In this work, we revisit the issue of adaptive power and performance management of data center server platforms. Traditional data center servers are statically configured and always over-provisioned to be able to handle peak load. We transform these statically configured data center servers to clairvoyant entities that can sense changes in the workload and dynamically scale in capacity to adapt to the requirements of the workload. The over-provisioned server capacity is transitioned to low-power states and they remain in those states for as long as the performance remains within given acceptable thresholds. The platform power expenditure is minimized subject to performance constraints. This is formulated as a performance-per-watt optimization problem and solved using analytical power and performance models. Coarse-grained optimizations at the platform-level are refined by local optimizations at the devices-level namely - the processor & memory subsystems. Our adaptive interleaving technique for memory power management yielded about 48.8% (26.7 kJ) energy savings compared to traditional techniques measured at 4.5%. Our adaptive platform power and performance management technique demonstrated 56.25% energy savings for memory-intensive workload, 63.75% savings for processor-intensive workload and 47.5% savings for a mixed workload while maintaining platform performance within given acceptable thresholds.

Published Article / This paper will discuss the final implementation of an Improved OPC data logging system and its improvements over the original. The improved solution focused on the hardware, software and administrative components of the system; taking the reliability and performance of each component into consideration. The software components include the database, the data acquisition and logging client application (DALC) and the various OPC servers; the hardware component includes the servers that will run the software components, power management and Redundant Array of Independents Disks (RAID) technologies; and the administrative component includes implementing automated routines to backup the important data and archive old logs.

Environmental awareness, production costs and operating expenses have provided a large incentive for the investigation of novel and more efficient fluid power technologies for decades. In the earth-moving sector, hydraulic hybrids have emerged as a highly efficient and affordable choice for the next generation hydraulic systems. Displacementcontrolled (DC) actuation has demonstrated that, when coupled with hydraulic hybrids, the engine power can be downsized by up to 50% leading to substantial savings. This concept has been realized by the authors‘ group on an excavator prototype where a secondary-controlled hydraulic hybrid drive was implemented on the swing. Actuatorlevel controls have been formulated by the authors‘ group but the challenge remains to effectively manage the system on the supervisory-level. In this paper, a power management controller is proposed to minimize fuel consumption while taking into account performance. The algorithm, a feedforward and cost-function combination considers operator commands, the DC actuators‘ power consumption and the power available from the engine and hydraulic hybrid as metrics. The developed strategy brings the technology closer to the predicted savings while achieving superior operability.

The Smartphone revolution and the Internet of Things (IoTs) have triggered rapid advances in complex system-on-chips (SoCs) that increasing provide more functionality within a tight power budget. Highly power efficient on die switched-capacitor voltage regulators suffer from large output voltage ripple preventing their widespread use in modern integrated circuits. With technology scaling and increasing architectural complexity, the number of transistors switching in a power domain is growing rapidly leading to major issues with respect to voltage noise. The large voltage and frequency guard-bands present in current microprocessor designs to combat voltage noise both degrade the performance and erode the energy efficiency of the design. In an effort to reduce guard-bands, adaptive clocking based systems combat the problem of voltage noise by adjusting the clock frequency during a voltage droop to avoid timing failure. This thesis presents an integrated power management and clocking scheme that utilizes clock-data compensation to achieve adaptive clocking. The design is capable of automatically con figuring the supply voltage given a target clock frequency for the load circuit. Furthermore, during a voltage droop the design adjusts clock frequency to meet critical path timing margins while simultaneously increasing the current delivered to the load to recover from the droop. The design was implemented in IBM's 130nm technology and simulation results show that the design is able to clock the load circuit from 30 MHz to 800 Mhz with current efficiencies as high as 97%.

Electric powered Unmanned Aerial Vehicles (UAVs) have emerged as a promi- nent aviation concept due to the advantageous such as stealth operation and zero emission. In addition, fuel cell powered electric UAVs are more attrac- tive as a result of the long endurance capability of the propulsion system. This dissertation investigates novel power management architecture for fuel cell and battery powered unmanned aerial vehicle propulsion application. The research work focused on the development of a power management system to control the hybrid electric propulsion system whilst optimizing the fuel cell air supplying system performances. The multiple power sources hybridization is a control challenge associated with the power management decisions and their implementation in the power electronic interface. In most applications, the propulsion power distribu- tion is controlled by using the regulated power converting devices such as unidirectional and bidirectional converters. The amount of power shared with the each power source is depended on the power and energy capacities of the device. In this research, a power management system is developed for polymer exchange membrane fuel cell and Lithium-Ion battery based hybrid electric propulsion system for an UAV propulsion application. Ini- tially, the UAV propulsion power requirements during the take-off, climb, endurance, cruising and maximum velocity are determined. A power man- agement algorithm is developed based on the UAV propulsion power re- quirement and the battery power capacity. Three power states are intro- duced in the power management system called Start-up power state, High power state and Charging power state. The each power state consists of the power management sequences to distribute the load power between the battery and the fuel cell system. A power electronic interface is developed Electric powered Unmanned Aerial Vehicles (UAVs) have emerged as a promi- nent aviation concept due to the advantageous such as stealth operation and zero emission. In addition, fuel cell powered electric UAVs are more attrac- tive as a result of the long endurance capability of the propulsion system. This dissertation investigates novel power management architecture for fuel cell and battery powered unmanned aerial vehicle propulsion application. The research work focused on the development of a power management system to control the hybrid electric propulsion system whilst optimizing the fuel cell air supplying system performances. The multiple power sources hybridization is a control challenge associated with the power management decisions and their implementation in the power electronic interface. In most applications, the propulsion power distribu- tion is controlled by using the regulated power converting devices such as unidirectional and bidirectional converters. The amount of power shared with the each power source is depended on the power and energy capacities of the device. In this research, a power management system is developed for polymer exchange membrane fuel cell and Lithium-Ion battery based hybrid electric propulsion system for an UAV propulsion application. Ini- tially, the UAV propulsion power requirements during the take-off, climb, endurance, cruising and maximum velocity are determined. A power man- agement algorithm is developed based on the UAV propulsion power re- quirement and the battery power capacity. Three power states are intro- duced in the power management system called Start-up power state, High power state and Charging power state. The each power state consists of the power management sequences to distribute the load power between the battery and the fuel cell system. A power electronic interface is developed with a unidirectional converter and a bidirectional converter to integrate the fuel cell system and the battery into the propulsion motor drive. The main objective of the power management system is to obtain the controlled fuel cell current profile as a performance variable. The relationship between the fuel cell current and the fuel cell air supplying system compressor power is investigated and a referenced model is developed to obtain the optimum compressor power as a function of the fuel cell current. An adaptive controller is introduced to optimize the fuel cell air supplying system performances based on the referenced model. The adaptive neuro-fuzzy inference system based controller dynamically adapts the actual compressor operating power into the optimum value defined in the reference model. The online learning and training capabilities of the adaptive controller identify the nonlinear variations of the fuel cell current and generate a control signal for the compressor motor voltage to optimize the fuel cell air supplying system performances. The hybrid electric power system and the power management system were developed in real time environment and practical tests were conducted to validate the simulation results.

Master of Science / Department of Electrical and Computer Engineering / Balasubramaniam Natarajan / Noel Schulz / With increasing costs for fuel there is a growing interest in improving fuel efficiency and performance of military vehicles by employing (1) hybrid drive train architecture; (2) reliable vehicle power system structure, and (3) effective power management strategies of multiple power sources (engine, battery and ultracapacitor) and vehicle electrical loads. However, current ruled-based power management strategies that focus primarily on traction fail to meet the rapidly increasing requirements of military vehicles, including: (1) better fuel economy; (2) the ability to support pulsed power weapon loads; (3) maintaining battery SOC for power offloading applications, and (4) the ability to perform load scheduling of vehicle non-traction electrical loads to save energy. In this thesis, we propose an optimal control based algorithm in conjunction with a rule-based control strategy to optimally manage three power sources (engine, battery and pulsed power supply module) and an effective power management solution for vehicle non-traction electrical loads such that: (1) all traction, non-traction and pulsed power needs are met; (2) power drawn from the engine for specific mission is minimized; (3) a certain desired battery SOC is guaranteed for offloading power, and (4) the ability to perform load scheduling based on different mission requirements. The proposed approach is validated using simulation of a mission specific profile and is compared with two other popular control strategies. The improvements in power efficiency, desired SOC level and ability to perform optimal load scheduling are demonstrated.

<p>The increasing amounts of vehicle emissions and vehicle energy consumption are major problems for the environment and energy conservation. Hybrid vehicles, which have less emissions and energy consumption, play more and more important roles in energy efficiency and sustainable development.</p> <p> </p> <p>The power management strategies of a parallel-through-the-road hybrid architecture vehicle are different from traditional hybrid electric vehicles since one additional dimension is added. To study power management strategies, a simplified model of the vehicle is developed. Four types of power management strategies have been discovered previously based on the simplified model, including dynamic programming model, equivalent consumption minimization strategy, proportional state-of-charge algorithm, and regression model. A new power management strategy, which is artificial neural network model, is developed. All these five power management strategies are compared, and the artificial neural network model is proven to have the best results among the implementable strategies.</p>

The portable electronics market is rapidly migrating towards more compact devices with multiple functionalities. Form factor, performance, cost and efficiency of these devices constitute the factors of merit of devices like cell phones, MP3 players and PDA's. With advancement in technology and more intelligent processors being used, there is a need for multiple high integrity voltage supplies for empowering the systems in portable electronic devices. Switched mode power supplies (SMPS's) are used to regulate the battery voltage. In an SMPS, maximum area is taken by the passive components such as the inductor and the capacitor. This work demonstrates a single inductor used in a buck converter with two output voltages from an input battery with voltage of value 3V. The main focus areas are low cross regulation between the outputs and supply of completely independent load current levels while maintaining desired values (1.2V,1.5V) within well controlled ripple levels. Dynamic hysteresis control is used for the single inductor dual output buck converter in this work. Results of schematic and post layout simulations performed in CADENCE prove the merits of this control method, such as nil cross regulation and excellent transient response.