Indiana University-Purdue University Indianapolis (IUPUI) / Lithium-ion battery is one kind of rechargeable battery, and also renewable, sustainable and portable. With the merits of high density, slow loss of charge when spare and no memory effect, lithium-ion battery is widely used in portable electronics and hybrid vehicles. Apart from its advantages, safety is a major concern for Lithium-ion batteries due to devastating incidents with laptop and cell phone batteries. Overcharge and over-discharge are two of the most common electrical abuses a lithium-ion battery suffers. In this thesis, a fuzzy-rule-based system is proposed to detect the over-charge and over-discharge failure in early time. The preliminary results for the failure signatures of overcharged and over-discharged lithium-ion are listed based on the experimental results under both room temperature and high temperature. A fuzzy-rule-based model utilizing these failure signatures is developed and validated. For over-charge case, the abnormal increase of the surface temperature and decrease of the voltage are captured. While for over discharge case, unusual temperature increase during overcharge phases and abnormal current decrease during overcharge phases are obtained. The inference engine for fuzzy-rule-based system is designed based on these failure signatures. An early warning signal will be given by this algorithm before the failure occurs. This failure detection and early warning system is verified to be effective through experimental validation. In the validation test, the proposed methods are successfully implemented in a real-time system for failure detection and early warning. The result of validation is compatible with the design expectation. Finally an accurate failure detection and early warning system is built and tested successfully.

Indiana University-Purdue University Indianapolis (IUPUI) / Reliability of the wide-area power system is becoming a greater concern as the power grid is growing. Delivering electric power from the most economical source through fewest and shortest transmission lines to customers frequently increases the stress on the system and prevents it from maintaining its stability. Events like loss of transmission equipment and phase to ground faults can force the system to cross its stability limits by causing the generators to lose their synchronism. Therefore, a helpful solution is detection of these dynamic events and prediction of instability. Decision Trees (DTs) were used as a pattern recognition tool in this thesis. Based on training data, DT generated rules for detecting event, predicting loss of synchronism, and selecting stabilizing control. To evaluate the accuracy of these rules, they were applied to testing data sets. To train DTs of this thesis, direct system measurements like generator rotor angles and bus voltage angles as well as calculated indices such as the rate of change of bus angles, the Integral Square Bus Angle (ISBA) and the gradient of ISBA were used. The initial method of this thesis included a response based DT only for instability prediction. In this method, time and location of the events were unknown and the one shot control was applied when the instability was predicted. The control applied was in the form of fast power changes on four different buses. Further, an event detection DT was combined with the instability prediction such that the data samples of each case was checked with event detection DT rules. In cases that an event was detected, control was applied upon prediction of instability. Later in the research, it was investigated that different control cases could behave differently in terms of the number of cases they stabilize. Therefore, a third DT was trained to select between two different control cases to improve the effectiveness of the methodology. It was learned through internship at Midwest Independent Transmission Operators (MISO) that post-event steady-state analysis is necessary for better understanding the effect of the faults on the power system. Hence, this study was included in this research.

Cette thèse est consacrée au développement de techniques de commande avancées pour des classes de systèmes non linéaires en général et pour des applications automobiles en particulier.Pour répondre au besoin du contrôle moteur, la première partie propose des nouveaux résultats théoriques sur la technique de commande non linéaire à base de modèles de type Takagi-Sugeno soumis à la saturation de la commande. La saturation de la commande est traitée en utilisant sa représentation polytopique ou une stratégie anti-windup.La deuxième partie porte sur la commande du système d'air d'un moteur turbocompressé à allumage commandé. Deux approches originales sont proposées. Dans la première, l'outil théorique concernant les modèles Takagi-Sugeno à commutation développé dans la première partie est directement appliqué. La seconde approche est basée sur une commande linéarisante robuste. L'originalité de ces approches multivariables consiste dans sa simplicité de mise en œuvre et son efficacité par rapport à celles qui existent dans la littérature.La dernière partie vise à développer des stratégies pour la gestion énergétique des systèmes électriques d'un véhicule obtenues en se basant sur le Principe du Minimum de Pontryagin. À cet effet, deux approches sont considérées : l'approche hors ligne d'optimisation utilisant les informations du futur concernant les conditions de roulage et l'approche en ligne qui est adaptée de la précédente. Ensuite, ces deux approches sont implémentées et évaluées dans un simulateur avancé. / This thesis addresses the development of some advanced control design tools for a class of nonlinear systems in general and for automotive systems in particular.Motivated by automotive applications, Part I proposes some novel theoretical results on control design for nonlinear systems under Takagi-Sugeno form subject to the control input saturation. The input saturation is dealt with by using its polytopic representation or an anti-windup strategy.Part II deals with our automotive application concerning the control of a turbocharged air system of a spark ignition engine. To this end, two novel control approaches are proposed in this part. For the first one, the theoretical design tool on switching Takagi-Sugeno controller developed in Part I is directly applied. The second one is based on a robust feedback linearization control technique. The originality of these MIMO approaches consist in their simplicity and effectiveness compared to other ones existing in the literature.Part III aims at developing the strategies, which are based on the Pontryagin's Minimum Principle in optimal control theory, for the energy management of the vehicular electric power systems in a hybrid engine configuration. To this end, both offline optimization approach using the future information of driving conditions and online implementable one have been developed and evaluated in an advanced simulator.

The objective of an Energy Control Center (ECC) is to ensure secure and economic operation of power system. The challenge to optimize power system operation, while maintaining system security and quality of power supply to customers, is increasing. Growing demand without matching expansion of generation and transmission facilities and more tightly interconnected power systems contribute to the increased complexity of system operation. Rising costs due to inflation and increased environmental concerns has made transmission, as well as generation systems to be operated closure to design limits, with smaller safety margins and hence greater exposure to unsatisfactory operating conditions following a disturbance. Investigations of recent blackouts indicate that the root cause of most of these major power system disturbances is voltage collapse. Information gathered and preliminary analysis, from the most recent blackout incident in North America on 14th August 2003, is pointing the finger on voltage instability due to some unexpected contingency. In this incident, reports indicate that approximately 50 million people were affected interruption from continuous supply for more than 15 hours. Most of the incidents are related to heavily stressed system where large amounts of real and reactive power are transported over long transmission lines while appropriate real and reactive power resources are not available to maintain normal system conditions. Hence, the problem of voltage stability and voltage collapse has become a major concern in power system planning and operation. Reliable operation of large scale electric power networks requires that system voltages and currents stay within design limits. Operation beyond those limits can lead to equipment failures and blackouts. In the last few decades, the problem of reactive power control for improving economy and security of power system operation has received much attention. Generally, the load bus voltages can be maintained within their permissible limits by reallocating reactive power generations in the system. This can be achieved by adjusting transformer taps, generator voltages, and switchable Ar sources. In addition, the system losses can be minimized via redistribution of reactive power in the system. Therefore, the problem of the reactive power dispatch can be optimized to improve the voltage profile and minimize the system losses as well. The Instability in power system could be relieved or at least minimized with the help of most recent developed devices called Flexible AC Transmission System (FACTS) controllers. The use of Flexible AC Transmission System (FACTS) controllers in power transmission system have led to many applications of these controllers not only to improve the stability of the existing power network resources but also provide operating flexibility to the power system. In the past, transmission systems were owned by regulated, vertically integrated utility companies. They have been designed and operated so that conditions in close proximity to security boundaries are not frequently encountered. However, in the new open access environment, operating conditions tend to be much closer to security boundaries, as transmission use is increasing in sudden and unpredictable directions. Transmission unbundling, coupled with other regulatory requirements, has made new transmission facility construction more difficult. In fact, there are numerous technical challenges emerging from the new market structure. There is an acute need for research work in the new market structure, especially in the areas of voltage security, reactive power support and congestion management. In the last few decades more attention was paid to optimal reactive power dispatch. Since the problem of reactive power optimization is non-linear in nature, nonlinear programming methods have been used to solve it. These methods work quite well for small power systems but may develop convergence problems as system size increases. Linear programming techniques with iterative schemes are certainly the most promising tools for solving these types of problems. The thesis presents efficient algorithms with different objectives for reactive power optimization. The approach adopted is an iterative scheme with successive power-flow analysis using decoupled technique, formulation and solution of the linear-programmingproblem with only upper-bound limits on the state variables. Further the thesispresents critical analysis of the three following objectives, Viz., •Minimization of the sum of the squares of the voltage deviations (Vdesired) •Minimization of sum of the squares of the voltage stability L indices (Vstability) •Minimization of real power losses (Ploss) Voltage stability problems normally occur in heavily stressed systems. While the disturbance leading to voltage collapse may be initiated by a variety of causes, the underlying problem is an inherent weakness in the power system. The factors contributing to voltage collapse are the generator reactive power /voltage control limits, load characteristics, characteristics of reactive compensation devices, and the action of the voltage control devices such as transformer On Load Tap Changers (OLTCs). Power system experiences abnormal operating conditions following a disturbance, and subsequently a reduction in the EHV level voltages at load centers will be reflected on the distribution system. The OLTCs of distribution transformers would restore distribution voltages. With each tap change operation, the MW and MVAR loading on the EHV lines would increase, thereby causing great voltage drops in EHV levels and increasing the losses. As a result, with each tap changing operation, the reactive output of generators throughout the system would increase gradually and the generators may hit their reactive power capability limits, causing voltage instability problems. Thus, the operation of certain OLTCs has a significant influence on voltage instability under some operating conditions. These transformers can be made manual to avoid possible voltage instability due to their operation during heavy load conditions. Tap blocking, based on local measurement of high voltage side of load tap changers, is a common practice of power utilities to prevent voltage collapse. The great advantage of this method is that it can be easily implemented, but does not guarantee voltage stability. So a proper approach for identification of critical OLTC s based on voltage stability criteria is essential to guide the operator in ECC, which has been proposed in this thesis. It discusses the effect of OLTCs with different objectives of reactive power dispatch and proposes a technique to identify critical OLTCs based on voltage stability criteria. The fast development of power electronics based on new and powerful semiconductor devices has led to innovative technologies, such as High Voltage DC transmission (HVDC) and Flexible AC Transmission System (FACTS), which can be applied in transmission and distribution systems. The technical and economicalBenefits of these technologies represent an alternative to the application in AC systems. Deregulation in the power industry and opening of the market for delivery of cheaper energy to the customers is creating additional requirements for the operation of power systems. HVDC and FACTS offer major advantages in meeting these requirements. .A method for co-ordinated optimum allocation of reactive power in AC/DC power systems by including FACTS controller UPFC, with an objective of minimization of the sum of the squares of the voltage deviations of all the load buses has been proposed in this thesis. The study results show that under contingency conditions, the presence of FACTS controllers has considerable impact on over all system voltage stability and also on power loss minimization.minimization of the sum of the squares of the voltage deviations of all the load buses has been proposed in this thesis. The study results show that under contingency conditions, the presence of FACTS controllers has considerable impact on over all system voltage stability and also on power loss minimization. As power systems grow in their size and interconnections, their complexity increases. For secure operation and control of power systems under normal and contingency conditions, it is essential to provide solutions in real time to the operator in ECC. For real time control of power systems, the conventional algorithmic software available in ECC are found to be inadequate as they are computationally very intensive and not organized to guide the operator during contingency conditions. Artificial Intelligence (AI) techniques such as, Expert systems, Neural Networks, Fuzzy systems are emerging decision support system tools which give fast, though approximate, but acceptable right solutions in real time as they mostly use symbolic processing with a minimum number of numeric computations. The solution thus obtained can be used as a guide by the operator in ECC for power system control. Optimum real and reactive power dispatch play an important role in the day-to-day operation of power systems. Existing conventional Optimal Power Flow (OPF) methods use all of the controls in solving the optimization problem. The operators can not move so many control devices within a reasonable time. In this context an algorithm using fuzzy-expert approach has been proposed in this thesis to curtail the number of control actions, in order to realize real time objectives in voltage/reactive power control. The technique is formulated using membership functions of linguistic variables such as voltage deviations at all the load buses and the voltage deviation sensitivity to control variables. Voltage deviations and controlling variables are translated into fuzzy set notations to formulate the relation between voltage deviations and controlling ability of controlling devices. Control variables considered are switchable VAR compensators, OLTC transformers and generator excitations. A fuzzy rule based system is formed to select the critical controllers, their movement direction and step size. Results show that the proposed approach is effective for improving voltage security to acceptable levels with fewer numbers of controllers. So, under emergency conditions the operator need not move all the controllers to different settings and the solution obtained is fast with significant speedups. Hence, the proposed method has the potential to be integrated for on-line implementation in energy management systems to achieve the goals of secure power system operation. In a deregulated electricity market, it may not be always possible to dispatch all of the contracted power transactions due to congestion of the transmission corridors. System operators try to manage congestion, which otherwise increases the cost of the electricity and also threatens the system security and stability. An approach for alleviation of network over loads in the day-to-day operation of power systems under deregulated environment is presented in this thesis. The control used for overload alleviation is real power generation rescheduling based on Relative Electrical Distance (RED) concept. The method estimates the relative location of load nodes with respect to the generator nodes. The contribution of each generator for a particular over loaded line is first identified , then based on RED concept the desired proportions of generations for the desired overload relieving is obtained, so that the system will have minimum transmission losses and more stability margins with respect to voltage profiles, bus angles and better transmission tariff. The results obtained reveal that the proposed method is not only effective for overload relieving but also reduces the system power loss and improves the voltage stability margin. The presented concepts are better suited for finding the utilization of resources generation/load and network by various players involved in the day-to-day operation of the system under normal and contingency conditions. This will help in finding the contribution by various players involved in the congestion management and the deviations can be used for proper tariff purposes. Suitable computer programs have been developed based on the algorithms presented in various chapters and thoroughly tested. Studies have been carried out on various equivalent systems of practical real life Indian power networks and also on some standard IEEE systems under simulated conditions. Results obtained on a modified IEEE 30 bus system, IEEE 39 bus New England system and four Indian power networks of EHV 24 bus real life equivalent power network, an equivalent of 36 bus EHV Indian western grid, Uttar Pradesh 96 bus AC/DC system and 205 Bus real life interconnected grid system of Indian southern region are presented for illustration purposes.

Devido à alta demanda energética e a grande complexidade dos atuais Sistemas Elétricos de Potência (SEPs), altamente interligados, torna-se cada vez mais importante para o operador do sistema, conhecer o estado atual do SEP. Além disso, dispor de ferramentas que permitam prever situações que venham a comprometer o bom funcionamento do sistema. Como um bom funcionamento, enquadra-se a continuidade do suprimento e perfis adequados de tensão elétrica, mesmo após a ocorrência de perturbações, o que pode ser afetado pelo fenômeno de instabilidade de tensão (ou colapso de tensão). Por isso, o objetivo deste trabalho é desenvolver uma metodologia de análise do colapso de tensão em tempo real considerando limites de potência ativa e reativa de geradores, a qual visa auxiliar o operador do sistema. Esta metodologia é dividida em cinco etapas. A primeira delas consiste em uma análise do caso base dos SEPs considerados, utilizando um algoritmo que permite estimar a margem de estabilidade de tensão do sistema, considerando os limites de potência ativa e reativa dos geradores. Esta primeira etapa utiliza a metodologia de fluxo de potência continuado, utilizando a carga e a tensão como parâmetros de continuação. A segunda etapa apresenta uma análise de contingências rápida considerando contingências simples de linhas de transmissão, seguindo o critério N-1. Nesta segunda etapa, foi utilizado o método de Look Ahead Modificado. A terceira etapa é uma análise apurada das contingências mais críticas, identificadas na etapa dois, a fim de verificar a presença de bifurcações induzidas por limites. Nesta terceira etapa, também se utilizou a metodologia de fluxo de potência continuado. Na quarta etapa, são aplicados todos os controle disponíveis no sistema, como inserção de banco de capacitores e ajuste do TAP dos transformadores, a fim de verificar qual seria o impacto dessas ações de controle no limite de operação segura do sistema, utilizando o método de Look Ahead Modificado. Essas quatro etapas possibilitam uma análise da estabilidade de tensão do sistema em tempo real. Por fim, é proposta uma quinta etapa de análise de contingências Offline, sendo uma análise mais precisa de todas as contingências, utilizando a metodologia de fluxo de potência continuado. Os SEPs analisados nesta dissertação foram o sistema de cinco barras Stagg, o sistema de quatorze barras padrão do Institute of Electrical and Electronics Engineers (IEEE) e o sistema de trinta barras padrão IEEE. / Due to the high energy demand and the high complexity of today's interconnected Electrical Power Systems (SEPs), it is becoming increasingly important for the system operator to know the current state of the SEP. In addition, have the tools to predict situations that may compromise the smooth operation of the system. As a good operation, the continuity of the supply and adequate voltage profiles are correct, even after the occurrence of disturbances, which can be affected by the phenomenon of voltage instability (or voltage collapse). Therefore, the objective of this work is to develop a methodology for the analysis of voltage collapse in real time considering the limits of active and reactive power of generators, which aims to assist the system operator. This methodology is divided into five steps. The first one consists of an analysis of the base case of the considered SEPs, using an algorithm that allows estimating the voltage stability margin of the system considering the limits of active and reactive power of the generators. This first step uses the continuous power flow methodology, using load and voltage as continuation parameters. The second stage presents a fast contingency analysis considering simple contingencies of transmission lines, following the criterion N-1. In this second step, the Modified Look Ahead method was used. The third step is an accurate analysis of the most critical contingencies, identified in step two, in order to verify the presence of limits-induced bifurcations. In this third step, we also used the continuous power flow methodology. In the fourth step, all available system controls, such as capacitor bank insertion and TAP adjustment of the transformers, are applied in order to verify the impact of these control actions on the safe operation limit of the system, using the Look Ahead Modified. These four steps enable a real-time analysis of the voltage stability of the system. Finally, a fifth stage of analysis of Offline contingencies is proposed, and a more precise analysis of all the contingencies using the methodology of continuous power flow is proposed. The SEPs analyzed in this dissertation were the Stagg five-bar system, the Institute of Electrical and Electronics Engineers (IEEE) standard fourteen bar system and the IEEE standard thirty-bar system.

Neste trabalho é apresentado um estudo de controladores aplicados a retificadores boost pré reguladores de alto fator de potência. A estratégia convencional, mais utilizada, é o controle por valores médios instantâneos que apresenta uma malha de corrente rápida e uma malha de tensão lenta. A frequência de corte desta última malha é baixa devido a ondulação de tensão de saída no dobro da frequência da rede que deve existir para apresentar uma corrente de entrada com baixa distorção harmônica. Esses controles apresentam um sobressinal elevado e transição lenta durante transitórios de carga, levando a elevação da tensão dos capacitores de saída. A técnica apresentada é um controlador digital com feedforward de potência de saída associado a uma malha de realimentação direta, também conhecido como autocontrole. Essa estratégia possibilita melhores resultados nos transitórios de carga possibilitando redução do capacitor de saída com reduzido sobressinal no transitório de carga. / In this work a study applied in controlled boost rectifiers with high power factor is presented. A most widely used conventional control strategy is the instant average current control, this kind of control have a fast current loop and a slow voltage loop.The cutoff frequency of the voltage loop is low because the output voltage ripple must be twice the frequency of the input network, that need to exist to provide an input current with low harmonic distortion. These controllers feature a high overshoot and a slow transition during the transient load what leads a high voltage in the output capacitors. The developed technique is a digital controller that operate with a feedforward output power associated with one cycle control. This strategy provides better results in the load transient, reducing the overshoot and alloying a reduction of the output capacitor.

Neste trabalho é apresentado um estudo de controladores aplicados a retificadores boost pré reguladores de alto fator de potência. A estratégia convencional, mais utilizada, é o controle por valores médios instantâneos que apresenta uma malha de corrente rápida e uma malha de tensão lenta. A frequência de corte desta última malha é baixa devido a ondulação de tensão de saída no dobro da frequência da rede que deve existir para apresentar uma corrente de entrada com baixa distorção harmônica. Esses controles apresentam um sobressinal elevado e transição lenta durante transitórios de carga, levando a elevação da tensão dos capacitores de saída. A técnica apresentada é um controlador digital com feedforward de potência de saída associado a uma malha de realimentação direta, também conhecido como autocontrole. Essa estratégia possibilita melhores resultados nos transitórios de carga possibilitando redução do capacitor de saída com reduzido sobressinal no transitório de carga. / In this work a study applied in controlled boost rectifiers with high power factor is presented. A most widely used conventional control strategy is the instant average current control, this kind of control have a fast current loop and a slow voltage loop.The cutoff frequency of the voltage loop is low because the output voltage ripple must be twice the frequency of the input network, that need to exist to provide an input current with low harmonic distortion. These controllers feature a high overshoot and a slow transition during the transient load what leads a high voltage in the output capacitors. The developed technique is a digital controller that operate with a feedforward output power associated with one cycle control. This strategy provides better results in the load transient, reducing the overshoot and alloying a reduction of the output capacitor.

Continued increase in system load leading to a reduction in operating margins, as well as the tendency to move towards a deregulated grid with renewable energy sources has increased the vulnerability of the grid to blackouts. Advanced intelligent techniques are therefore required to design new monitoring schemes that enable smart grid operation in a secure and robust manner. As the grid is highly interconnected, monitoring of transmission and distribution systems is increasingly relying on digital communication. Conventional security assessment techniques are slow, hampering real-time decision making. Hence, there is a need to develop fast and accurate security monitoring techniques. Intelligent techniques that are capable of processing large amounts of captured data are finding increasing scope as essential enablers for the smart grid. The research work presented in this thesis has evolved from the need for enhanced monitoring in transmission and distribution grids. The potential of intelligent techniques for enhanced system monitoring has been demonstrated for disturbed scenarios in an integrated power system. In transmission grids, one of the challenging problems is network partitioning, also known as network area-decomposition. In this thesis, an approach based on relative electrical distance (RED) has been devised to construct zonal dynamic equivalents such that the dynamic characteristics of the original system are retained in the equivalent system within the desired accuracy. Identification of coherent generators is another key aspect in power system dynamics. In this thesis, a support vector clustering-based coherency identification technique is proposed for large interconnected multi-machine power systems. The clustering technique is based on coherency measure which is formulated using the generator rotor measurements. These rotor measurements can be obtained with the help of Phasor Measurement Units (PMUs). In distribution grids, accurate and fast fault identification of faults is a key challenge. Hence, an automated fault diagnosis technique based on multi class support vector machines (SVMs) has been developed in this thesis. The proposed fault location scheme is capable of accurately identify the fault type, location of faulted line section and the fault impedance in the distributed generation (DG) systems. The proposed approach is based on the three phase voltage and current measurements available at all the sources i.e. substation and at the connection points of DGs. An approach for voltage instability monitoring in 3-phase distribution systems has also been proposed in this thesis. The conventional single phase L-index measure has been extended to a 3-phase system to incorporate information pertaining to unbalance in the distribution system. All the approaches proposed in this thesis have been validated using standard IEEE test systems and also on practical Indian systems.

In the modern generation, Electric Power has become one of the fundamental needs for humans to survive. This is due to the dependence of continuous availability of power. However, for electric power to be available to the society, it has to pass through a number of complex stages. Through each stage power quality problems are experienced on the grid. Under-voltages and over-voltages are the most common electric problems experienced on the grid, causing industries and business firms losses of Billions of dollars each year. Researchers from different regions are attracted by an idea that will overcome all the electrical issues experienced in the traditional grid using Artificial Intelligence (AI). The idea is said to provide electric power that is sustainable, economical, reliable and efficient to the society based on Evolutionary Algorithms (EAs). The idea is Smart Grid. The research focused on Power Quality Optimization in Smart Grid based on improved Differential Evolution (DE), with the objective functions to minimize voltage swells, counterbalance voltage sags and eliminate voltage surges or spikes, while maximizing the power quality. During Differential Evolution improvement research, elimination of stagnation, better and fast convergence speed were achieved based on modification of DE’s mutation schemes and parameter control selection. DE/Modi/2 and DE/Modi/3 modified mutation schemes proved to be the excellent improvement for DE algorithm by achieving excellent optimization results with regards to convergence speed and elimination of stagnation during simulations. The improved DE was used to optimize Power Quality in smart grid in combination with the reconfigured and modified Dynamic Voltage Restorer (DVR). Excellent convergence results of voltage swells and voltage sags minimization were achieved based on application of multi-objective parallel operation strategy during simulations. MATLAB was used to model the proposed solution and experimental simulations. / Electrical and Mining Engineering / M. Tech. (Electrical Engineering)

Indiana University-Purdue University Indianapolis (IUPUI) / Hydraulic wind power transfer systems deliver the captured energy by the blades to the generators differently. In the conventional systems this task is carried out by a gearbox or an intermediate medium. New generation of wind power systems transfer the captured energy by means of high-pressure hydraulic fluids. A hydraulic pump is connected to the blades shaft at a high distance from the ground, in nacelle, to pressurize a hydraulic flow down to ground level equipment through hoses. Multiple wind turbines can also pressurize a flow sending to a single hose toward the generator. The pressurized flow carries a large amount of energy which will be transferred to the mechanical energy by a hydraulic motor. Finally, a generator is connected to the hydraulic motor to generate electrical power. This hydraulic system runs under two main disturbances, wind speed fluctuations and load variations. Intermittent nature of the wind applies a fluctuating torque on the hydraulic pump shaft. Also, variations of the consumed electrical power by the grid cause a considerable load disturbance on the system. This thesis studies the hydraulic wind power transfer systems. To get a better understanding, a mathematical model of the system is developed and studied utilizing the governing equations for every single hydraulic component in the system. The mathematical model embodies nonlinearities which are inherited from the hydraulic components such as check valves, proportional valves, pressure relief valves, etc. An experimental prototype of the hydraulic wind power transfer systems is designed and implemented to study the dynamic behavior and operation of the system. The provided nonlinear mathematical model is then validated by experimental result from the prototype. Moreover, this thesis develops a control system for the hydraulic wind power transfer systems. To maintain a fixed frequency electrical voltage by the system, the generator should remain at a constant rotational speed. The fluctuating wind speed from the upstream, and the load variations from the downstream apply considerable disturbances on the system. A controller is designed and implemented to regulate the flow in the proportional valve and as a consequence the generator maintains its constant speed compensating for load and wind turbine disturbances. The control system is applied to the mathematical model as well as the experimental prototype by utilizing MATLAB/Simulink and dSPACE 1104 fast prototyping hardware and the results are compared.