In this thesis the eigenstructure (eigenvalues and eigenvectors) assignment technique based algorithm has been developed for the design of controllers for power system applications. The application of the algorithm is demonstrated by designing power system stabilizers (PSSs) that are extensively used to address the small-signal rotor angle stability problems in power systems. In the eigenstructure assignment technique, the critical eigenvalues can be relocated as well as their associated eigenvectors can be modified. This method is superior and yield better dynamical performance compared to the widely used frequency domain design method, in which only the critical eigenvalues are relocated and no attempt is made to modify the eigenvectors. The reviewed published research has demonstrated successful application of the eigenstructure assignment technique in the design of controllers for small control systems. However, the application of this technique in the design of controllers for power systems has not been investigated rigorously. In contrast to a small system, a power system has a very large number state variables compared to the combined number of system inputs and outputs. Therefore, the eigenstructure assignment technique that has been successfully applied in the design of controllers for small systems could not be applied as is in the design of power system controllers. This thesis proposes a novel approach to the application of the eigenstructure assignment technique in the design of power system controllers. In this new approach, a multi-objective nonlinear optimization problem (MONLOP) is formulated by quantifying different design objectives as a function of free parametric vectors. Then the MONLOP is solved for the free parametric vectors using a nonlinear optimization technique. Finally, the solution of the controller parameters is obtained using the solved free parametric vectors. The superiority of the proposed method over the conventional frequency domain method is demonstrated by designing controllers for three different systems and validating the controllers through nonlinear transient simulations. One of the cases includes design of a PSS for the Manitoba Hydro system having about 29,000 states variables, which demonstrates the applicability of the proposed algorithm for a practical real-world system.

The possible benefits of employing inerters in automotive suspensions are explored for passenger comfort and handling. Different suspension strut designs in terms of the relative arrangement of springs, dampers and inerters have been considered and their performance compared with that of a conventional system. An alternate method of electrically realizing complex mechanical circuits by using a linear motor (or a rotary motor with an appropriate mechanism) and a shunt circuit is then proposed and evaluated for performance. However, the performance improvement is shown from simulations to be significant only for very stiff suspensions, unlike those in passenger vehicles. Hence, the concept is not taken up for prototyping. Variable damping can be implemented in suspension systems in various ways, for example, using magneto-rheological (MR) fluids, proportional valves, or variable shunt resistance with a linear electromagnetic motor. Hence for a generic variable damping system, a control algorithm is developed which can provide more comfort and better handling simultaneously compared to a passive system. After establishing through simulations that the proposed adaptive control algorithm can demonstrate a performance better than some controllers in prior-art, it is implemented on an actual vehicle (Cadillac STS) which is equipped with MR dampers and several sensors. In order to maintain the controller economical so that it is practically viable, an estimator is developed for variables which require expensive sensors to measure. The characteristic of the MR damper installed in the vehicle is obtained through tests as a 3-dimensional map relating suspension speed, input current and damping force and then used as a look-up table in the controller. Experiments to compare the performance of different controllers are carried out on smooth and rough roads and over speed bumps.

In this thesis the eigenstructure (eigenvalues and eigenvectors) assignment technique based algorithm has been developed for the design of controllers for power system applications. The application of the algorithm is demonstrated by designing power system stabilizers (PSSs) that are extensively used to address the small-signal rotor angle stability problems in power systems. In the eigenstructure assignment technique, the critical eigenvalues can be relocated as well as their associated eigenvectors can be modified. This method is superior and yield better dynamical performance compared to the widely used frequency domain design method, in which only the critical eigenvalues are relocated and no attempt is made to modify the eigenvectors. The reviewed published research has demonstrated successful application of the eigenstructure assignment technique in the design of controllers for small control systems. However, the application of this technique in the design of controllers for power systems has not been investigated rigorously. In contrast to a small system, a power system has a very large number state variables compared to the combined number of system inputs and outputs. Therefore, the eigenstructure assignment technique that has been successfully applied in the design of controllers for small systems could not be applied as is in the design of power system controllers. This thesis proposes a novel approach to the application of the eigenstructure assignment technique in the design of power system controllers. In this new approach, a multi-objective nonlinear optimization problem (MONLOP) is formulated by quantifying different design objectives as a function of free parametric vectors. Then the MONLOP is solved for the free parametric vectors using a nonlinear optimization technique. Finally, the solution of the controller parameters is obtained using the solved free parametric vectors. The superiority of the proposed method over the conventional frequency domain method is demonstrated by designing controllers for three different systems and validating the controllers through nonlinear transient simulations. One of the cases includes design of a PSS for the Manitoba Hydro system having about 29,000 states variables, which demonstrates the applicability of the proposed algorithm for a practical real-world system.

Functional electrical stimulation (FES) systems have been developed to help restore various neuromuscular functions in individuals with neurological disorders leading to paralysis. Most of the current FES systems are designed for specific neuroprosthesis applications (i.e., walking, grasping, bladder voiding, coughing, etc.) and when one intends to use them in other custom made applications they are very limited due to a lack of functionality and flexibility in hardware and programmability. This prevents effective and efficient development of customized neuroprostheses. Research and development efforts at the Rehabilitation Engineering Laboratory at the University of Toronto were being carried out with an objective to produce a new, fully programmable and portable FES system. This thesis presents a novel proof-of-concept prototype controller for use in the new FES system. The controller subsystem manages and controls the overall FES system including the real-time decoding and execution of stimulation, data acquisition, external systems interfaces and user interface.

Government regulations and growing concerns regarding global warming has lead to an increasing number of passenger vehicles on the roads today that are not powered by the conventional internal combustion (IC) engine. Automotive manufacturers have introduced electric powertrains over the last 10 years which have introduced new challenges regarding powering accessory loads historically reliant on the mechanical energy of the IC engine. High density batteries are used to store the electrical energy required by an electric powertrain and due to their relatively narrow acceptable temperature range, require liquid cooling. The cooling system in place currently utilizes the A/C compressor for cooling and a separate electric element for heating which is energy expensive when the source of energy is electricity. The proposed solution is a thermoelectric heat pump for both heating and cooling. A model predictive controller (MPC) is designed, implemented and tested to optimize the operation of the thermoelectric heat pump. The model predictive controller is chosen due to its ability to accept multiple constrained inputs and outputs as well as optimize the system according to a cost function which may consist of any parameters the designer chooses. The system is highly non-linear and complex therefore both physical modelling and system identi cation were used to derive an accurate model of the system. A steepest descent algorithm was used for optimization of the cost function. The controller was tested in a test bench environment. The results show the thermoelectric heat pump does hold the battery at the speci ed set point however more optimization was expected from the controller. The controller fell short of expectation due to operational restriction enforced during design meant to simplify the problem. The MPC controller is capable of much better performance through adding more detail to the model, an improved optimization algorithm and allowing more flexibility in set point selection.

The speed of fuzzy controllers implemented on dedicated hardware is adequate for control of any physical process, but too slow for todays high-complexity data networks. Defuzzification has been the bottleneck for fast implementations due to the large number of computationally expensive multiplication and division operations. In this thesis, we propose a high-speed fuzzy inferential system based on log-domain arithmetic, which only requires addition and subtraction operations. The system is implemented on a Xilinx Virtex-II FPGA with a processing speed of 67.6 MFLIPS having a maximum combinational path delay of 4.2 ns. It is a clear speedup compared to the reported fastest 50 MFLIPS implementation. A pipelined version of the controller is also implemented, which achieves a speed of 248.7 MFLIPS. Although a small approximation error is introduced, software simulation and hardware implementation on FPGA confirm high similarity of the outputs for control surfaces and a number of second-order plants. / Software Engineering and Intelligent Systems

Thesis (D. Mus. Arts)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [65]-73).

A origem da controladoria no Brasil está relacionada a instalação das primeiras empresas multinacionais norte-americanas no país. Na época a função do profissional da controladoria estava ligada à área financeira ou da contabilidade, devido à habilidade de trabalhar com informações econômico-financeiras, bem como, pelo conhecimento sistêmico da organização. Do surgimento da controladoria no Brasil até os dias atuais, o país passou por grandes transformações, especialmente nos aspectos econômicos e sociais, pois o mundo se globalizou, reduzindo as fronteiras entre os países. Para que o país pudesse se inserir neste contexto globalizado foi necessário que o brasileiro se adaptasse a uma nova forma de fazer negócios a nível mundial. Além do que, para se manterem competitivas, as organizações brasileiras passaram a demandar, cada vez mais melhorias em seus processos e controles. Diante disso, este trabalho tem como objetivo evidenciar como ocorreu a evolução da controladoria no Brasil, através do estudo da sua origem, evolução do perfil, atribuições do controller e identificação das principais atribuições da controladoria no país. Quanto ao método classifica-se esta pesquisa como descritiva, sendo conduzida através de pesquisa bibliográfica. Os resultados demonstram que a evolução da controladoria no Brasil, acompanhou a evolução da controladoria a nível mundial, uma vez que ocorreu a partir das necessidades de informações e controles que acompanharam a evolução natural da economia brasileira. Neste contexto, a controladoria passou a ser um importante player da gestão empresarial, pois auxilia os gestores durante todo o processo decisório a fim, de garantir a eficácia do negócio. Entretanto no campo semântico conclui-se que a controladoria ainda precisa evoluir, pois não existe consenso entre os pesquisadores sobre o que é a controladoria, sobre as suas funções e atribuições. / The origin of controllership in Brazil is connected to the settlement of the first US multinational companies in the country. Back then, the function of a controller was linked to finance or accounting, because of the ability to work with economic and financial pieces of information as well as the systemic knowledge of the company. From the beginning of controllership in Brazil to nowadays the country has gone through major changes, especially economic and social aspects as the world has globalized, reducing the boundaries between countries. For the country to enter this globalized context it was necessary for the Brazilian one to adapt to a new way of doing business globally. Moreover, to remain competitive Brazilian companies began demanding more and more improvements in their processes and controls. Thus, this work aims to show how the evolution of controllership was in Brazil, through the controllership origin study, profile evolution checking and the controller assignments and identifying the main tasks of controllership in the country. As for the method this research is descriptive, driven by bibliographic search. The results show that the evolution of controllership in Brazil followed the global controllership evolution once it occurred from the information requirements and controls that followed natural Brazilian economy evolution. In this context, controllership has become a major player in business management, as it assists managers throughout the decision-making process in order to ensure business effectiveness. However, in the semantic field controllership still needs to evolve as there is no consensus among researchers about what controllership is, on its functions and tasks.

A origem da controladoria no Brasil está relacionada a instalação das primeiras empresas multinacionais norte-americanas no país. Na época a função do profissional da controladoria estava ligada à área financeira ou da contabilidade, devido à habilidade de trabalhar com informações econômico-financeiras, bem como, pelo conhecimento sistêmico da organização. Do surgimento da controladoria no Brasil até os dias atuais, o país passou por grandes transformações, especialmente nos aspectos econômicos e sociais, pois o mundo se globalizou, reduzindo as fronteiras entre os países. Para que o país pudesse se inserir neste contexto globalizado foi necessário que o brasileiro se adaptasse a uma nova forma de fazer negócios a nível mundial. Além do que, para se manterem competitivas, as organizações brasileiras passaram a demandar, cada vez mais melhorias em seus processos e controles. Diante disso, este trabalho tem como objetivo evidenciar como ocorreu a evolução da controladoria no Brasil, através do estudo da sua origem, evolução do perfil, atribuições do controller e identificação das principais atribuições da controladoria no país. Quanto ao método classifica-se esta pesquisa como descritiva, sendo conduzida através de pesquisa bibliográfica. Os resultados demonstram que a evolução da controladoria no Brasil, acompanhou a evolução da controladoria a nível mundial, uma vez que ocorreu a partir das necessidades de informações e controles que acompanharam a evolução natural da economia brasileira. Neste contexto, a controladoria passou a ser um importante player da gestão empresarial, pois auxilia os gestores durante todo o processo decisório a fim, de garantir a eficácia do negócio. Entretanto no campo semântico conclui-se que a controladoria ainda precisa evoluir, pois não existe consenso entre os pesquisadores sobre o que é a controladoria, sobre as suas funções e atribuições. / The origin of controllership in Brazil is connected to the settlement of the first US multinational companies in the country. Back then, the function of a controller was linked to finance or accounting, because of the ability to work with economic and financial pieces of information as well as the systemic knowledge of the company. From the beginning of controllership in Brazil to nowadays the country has gone through major changes, especially economic and social aspects as the world has globalized, reducing the boundaries between countries. For the country to enter this globalized context it was necessary for the Brazilian one to adapt to a new way of doing business globally. Moreover, to remain competitive Brazilian companies began demanding more and more improvements in their processes and controls. Thus, this work aims to show how the evolution of controllership was in Brazil, through the controllership origin study, profile evolution checking and the controller assignments and identifying the main tasks of controllership in the country. As for the method this research is descriptive, driven by bibliographic search. The results show that the evolution of controllership in Brazil followed the global controllership evolution once it occurred from the information requirements and controls that followed natural Brazilian economy evolution. In this context, controllership has become a major player in business management, as it assists managers throughout the decision-making process in order to ensure business effectiveness. However, in the semantic field controllership still needs to evolve as there is no consensus among researchers about what controllership is, on its functions and tasks.

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