Controle vetorial de velocidade de uma máquina de indução sem mancais trifásica com bobinado dividido utilizando estimação neural de fluxo

This work describes the study and the implementation of the vector speed control for a three-phase Bearingless induction machine with divided winding of 4 poles and 1,1 kW using the neural rotor flux estimation. The vector speed control operates together with the radial positioning controllers and with the winding currents controllers of the stator phases. For the radial positioning, the forces controlled by the internal machine magnetic fields are used. For the radial forces optimization , a special rotor winding with independent circuits which allows a low rotational torque influence was used. The neural flux estimation applied to the vector speed controls has the objective of compensating the parameter dependences of the conventional estimators in relation to the parameter machine s variations due to the temperature increases or due to the rotor magnetic saturation. The implemented control system allows a direct comparison between the respective responses of the speed and radial positioning controllers to the machine oriented by the neural rotor flux estimator in relation to the conventional flux estimator. All the system control is executed by a program developed in the ANSI C language. The DSP resources used by the system are: the Analog/Digital channels converters, the PWM outputs and the parallel and RS-232 serial interfaces, which are responsible, respectively, by the DSP programming and the data capture through the supervisory system

Controle vetorial de velocidade de um motor de indução trifásico com estimação neural de fluxo

This work describes the study and the implementation of the speed control for a three-phase induction motor of 1,1 kW and 4 poles using the neural rotor flux estimation. The vector speed control operates together with the winding currents controller of the stator phasis. The neural flux estimation applied to the vector speed controls has the objective of compensating the parameter dependences of the conventional estimators in relation to the parameter machine s variations due to the temperature increases or due to the rotor magnetic saturation. The implemented control system allows a direct comparison between the respective responses of the speed controls to the machine oriented by the neural rotor flux estimator in relation to the conventional flux estimator. All the system control is executed by a program developed in the ANSI C language. The main DSP recources used by the system are, respectively, the Analog/Digital channels converters, the PWM outputs and the parallel and RS-232 serial interfaces, which are responsible, respectively, by the DSP programming and the data capture through the supervisory system

Proposta de integração das redes de comunicação da COSERN como uma solução de contigêncvia em caso de falhas nos enlaces do backbone de automação

T'his dissertation proposes alternative models to allow the interconnectioin of the data communication networks of COSERN Companhia Energética do Rio Grande do Norte. These networks comprise the oorporative data network, based on TCP/IP architecture, and the automation system linking remote electric energy distribution substations to the main Operatin Centre, based on digital radio links and using the IEC 60870-5-101 protoco1s. The envisaged interconnection aims to provide automation data originated from substations with a contingent route to the Operation Center, in moments of failure or maintenance of the digital radio links. Among the presented models, the one chosen for development consists of a computational prototype based on a standard personal computer, working under LINUX operational system and running na application, developesd in C language, wich functions as a Gateway between the protocols of the TCP/IP stack and the IEC 60870-5-101 suite. So, it is described this model analysis, implementation and tests of functionality and performance. During the test phase it was basically verified the delay introduced by the TCP/IP network when transporting automation data, in order to guarantee that it was cionsistent with the time periods present on the automation network. Besides , additional modules are suggested to the prototype, in order to handle other issues such as security and prioriz\ation of the automation system data, whenever they are travesing the TCP/IP network. Finally, a study hás been done aiming to integrate, in more complete way, the two considered networks. It uses IP platform as a solution of convergence to the communication subsystem of na unified network, as the most recente market tendencies for supervisory and other automation systems indicate

Uma proposta de regulador nebuloso para geradores eólicos de indução

This work presents a proposal for a voltage and frequency control system for a wind power induction generator. It has been developed na experimental structure composes basically by a three phase induction machine, a three phase capacitor and a reactive static Power compensator controlled by histeresys. lt has been developed control algorithms using conventional methods (Pl control) and linguistic methods (using concepts of logic and fuzzy control), to compare their performances in the variable speed generator system. The control loop was projected using the ADJDA PCL 818 model board into a Pentium 200 MHz compu ter. The induction generator mathematical model was studied throught Park transformation. It has been realized simulations in the Pspice@ software, to verify the system characteristics in transient and steady-state situations. The real time control program was developed in C language, possibilish verify the algorithm performance in the 2,2kW didatic experimental system

Técnica de controle adaptativo robusto aplicada a filtros ativos de potência e paralelo

The Methods for compensation of harmonic currents and voltages have been widely used since these methods allow to reduce to acceptable levels the harmonic distortion in the voltages or currents in a power system, and also compensate reactive. The reduction of harmonics and reactive contributes to the reduction of losses in transmission lines and electrical machinery, increasing the power factor, reduce the occurrence of overvoltage and overcurrent. The active power filter is the most efficient method for compensation of harmonic currents and voltages. The active power filter is necessary to use current and voltage controllers loop. Conventionally, the current and voltage control loop of active filter has been done by proportional controllers integrative. This work, investigated the use of a robust adaptive control technique on the shunt active power filter current and voltage control loop to increase robustness and improve the performance of active filter to compensate for harmonics. The proposed control scheme is based on a combination of techniques for adaptive control pole placement and variable structure. The advantages of the proposed method over conventional ones are: lower total harmonic distortion, more flexibility, adaptability and robustness to the system. Moreover, the proposed control scheme improves the performance and improves the transient of active filter. The validation of the proposed technique was verified initially by a simulation program implemented in C++ language and then experimental results were obtained using a prototype three-phase active filter of 1 kVA

Estudo e implementação em plantas físicas de um controlador preditivo generalizado com restrições

This work shows a study about the Generalized Predictive Controllers with Restrictions and their implementation in physical plants. Three types of restrictions will be discussed: restrictions in the variation rate of the signal control, restrictions in the amplitude of the signal control and restrictions in the amplitude of the Out signal (plant response). At the predictive control, the control law is obtained by the minimization of an objective function. To consider the restrictions, this minimization of the objective function is done by the use of a method to solve optimizing problems with restrictions. The chosen method was the Rosen Algorithm (based on the Gradient-projection). The physical plants in this study are two didactical systems of water level control. The first order one (a simple tank) and another of second order, which is formed by two tanks connected in cascade. The codes are implemented in C++ language and the communication with the system to be done through using a data acquisition panel offered by the system producer

Arquitetura de Software para Barcos Robóticos

We propose in this work a software architecture for robotic boats intended to act in diverse aquatic environments, fully autonomously, performing telemetry to a base station and getting this mission to be accomplished. This proposal aims to apply within the project N-Boat Lab NatalNet DCA, which aims to empower a sailboat navigating autonomously. The constituent components of this architecture are the memory modules, strategy, communication, sensing, actuation, energy, security and surveillance, making these systems the boat and base station. To validate the simulator was developed in C language and implemented using the graphics API OpenGL resources, whose main results were obtained in the implementation of memory, performance and strategy modules, more specifically data sharing, control of sails and rudder and planning short routes based on an algorithm for navigation, respectively. The experimental results, shown in this study indicate the feasibility of the actual use of the software architecture developed and their application in the area of autonomous mobile robotics

Otimização de um sistema de distribuição predial de água fria: estudo de caso

This dissertation presents a methodology to the optimization of a predial system of cold water distribution. It s about a study of a case applied to the Tropical Buzios Residential Condominium, located in the Búzio s Beach, Nísia Floresta city, the east coast of the Rio Grande do Norte state, twenty kilometers far from Natal. The design of cold water distribution networks according to Norm NBR 5626 of the ABNT - Brazilian Association of Techniques Norms, does not guarantee that the joined solution is the optimal solution of less cost. It s necessary the use of an optimization methodology, that supplies us, between all the possible solutions, the minimum cost solution. In the optimization process of the predial system of water distribution of the Tropical Búzios Condominium, is used Method Granados, that is an iterative algorithm of optimization, based on the Dynamic Programming, that supplies the minimum cost s network, in function of the piezometric quota of the reservoir. For the application of this Method in ramifies networks, is used a program of computer in C language. This process is divided in two stages: attainment of the previous solution and reduction of the piezometric quota of headboard. In the attainment of the previous solution, the minors possible diameters are used that guarantee the limit of maximum speed and the requirements of minimum pressures. The piezometric quota of headboard is raised to guarantee these requirements. In the second stage of the Granados Method, an iterative process is used and it objective is to reduce the quota of headboard gradually, considering the substitution of stretches of the network pipes for the subsequent diameters, considering a minimum addition of the network cost. The diameter change is made in the optimal stretch that presents the lesser Exchange Gradient. The process is locked up when the headboard quota of desired is reached. The optimized network s material costs are calculated, and is made the analysis of the same ones, through the comparison with the conventional network s costs

Automação residencial microcontrolada para transmissão de dados via rede elétrica

This work deals with the specification and the implementation of a protocol for controlling communication between two programmable interface microcontrollers (PIC), using power line communication (PLC), making communication more secure and economically viable. The Protocol was implemented in C language, with reference to some protocols developed for automotive use. A circuit to test the communication between the PLC and the Protocol was also implemented.

O ritual simbólico do Ctrl+C (copiar ) e Ctrl+V (colar) no ensino médio

Nowadays, technology has a direct influence on the relationship student and teacher have with language. The internet is a powerful tool in helping work with the language and, through it, the knowledge comes to the student easily and intensely. Furthermore, this facility has enhanced and made visible what has been called, within the University community, "plagiarism generation." This work assumes that this generation has, in their written texts, symbolic movements similar to those of "copy and paste" applied to research work carried out by high school students. Taking this as starting point, this dissertation aims to analyze how high school students of the 1st year from a school in Natal (RN) construct texts, under the movements known as "Ctrl + c" and "Ctrl + v", with reference to the text of the "other". More specific issues are behind the general objective, namely: 1. how the student appropriates the source-text when he copies and pastes? 2. What are the categories of analysis that allow us to look analytically and theoretically for the "ctrl + c / ctrl + v" practice made by the student? 2. how the studies developed in the fields of "Genetic Criticism" (Grésillon, 1987), the "school manuscripts" (Calil, 2004) and "paraphrase" (Fuchs, 1982) may help in working with writing in the classroom standing as a possible way to minimize the copy and paste effects in the students texts? Thus, we observe the categories of analysis that allow us to look, theoretically and analytically, for the symbolic ritual of the "ctrl + c" (copy) and "ctrl + v" (paste) in high school. Our study shows that the student text is a "hybrid body" whose writing is a drawing entanglement because of the presence of the foreign text, verbatim, and the presence of linguistic elements to paraphrase the original text.This textual embodiment has, behind it, certain operations, namely: replacing, moving, adding and deleting statements. Given the specificity of the data and the research objectives, this study aligns with qualitative research methods (SILVERMAN, 2009) and falls within the knowledge field of Applied Linguistics, which is characterized especially by investigating problems, phenomena in which language in a real situation is taken as central (BRUMFIT, 1995).Theoretically, our work follows the approach of studies on the paraphrase (Fuchs, 1982, 1994a, 1994b; DAUNAY, 1997, 1999, 2002a, 2002b), the studies developed in the field of Genetic Criticism (Grésillon, 1987, 1994, 1992, 2008 ) and those developed by Eduardo Calil (2004) on "school manuscripts"

Consumo c(l)iente: abordagem do gênero anúncio publicitário em livros didáticos de língua portuguesa do ensino médio

Portuguese language textbooks, according to what has been preconized on the official document to education, have been configured on discursive genres imported from diverse spheres of human activity. Adverts, genre of ample social circulation, spread from the Advertising sphere to the schools and started being approached by these collectaneas as an object and a tool for teaching. Therefore, this research deals with the approach of ads in Portugese textbooks. These discursive practices matter for the impact or appeal they exert over the (new) consumers, among which High School students; for their representation in the capitalist system, which guides us on our relationships and social practices; and for the mix of languages that end up at their composition, once they encapsulate the spirit of our time, par excellence, the one from the verbal-visual genres. To understand the treatment given to these advertising pieces, from questions/commentaries related to them, two collections were selected by the Programa Nacional do Livro Didático – Textbook National Program (PNLD 2012) among the ones more used by public High Schools in Natal/RN. From Applied Linguistics, from mestizo, nomadic and inter/transdisciplinary identity (MOITA LOPES, 2009), this study falls within the discursive chain of the interpretive tradition of historical-cultural approach (FREITAS, 2010) and names the Bakhtin Circle and its language‟s dialogical conception as inescapable partners. The data of the colletaneas show that the genre approach can happen as concrete utterance, as linguistic artifact and as hybrid, at work with questions and without questions, with the predominance of its occurrence in the portion of the volume devoted to the study of grammar. In the literature chapters and production/interpretation of compositions, it insert is incipient or it doesn‟t happen in the volume. Such a provision has implications for multiliteracies (ROJO, 2012) of the citizen student, once the lack or the abundance of critical reading proposals for this genre, that demand from the student the exercise of knowledge that is necessary to the construction of linguistic and social meanings, can be responsible for guide to a more conscious consumerism (material and cultural) by the chief customers of the work under review. The approaches of the genres seems to indicate a gradual transition that such material have undergone, which means, from the focus on clauses to the focus on utterances, or even the approach as linguistic artifact to hybrid and the concrete utterance, in search of overcoming the traditional tendency of taking advantage of formal aspects of the language, to the detriment of enunciative ones, and for coming into harmony with the guidelines and parameters of teaching in contemporary times, bringing the school duties close to the rights in life.