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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Controle Robusto Aplicado a Conversor Buck-Boost em Sistemas Fotovoltaicos

Carvalho Neto, Jo?o Teixeira de 30 July 2012 (has links)
Made available in DSpace on 2014-12-17T14:56:09Z (GMT). No. of bitstreams: 1 JoaoTCN_DISSERT.pdf: 3199747 bytes, checksum: e80bdfe5ca1e9afb305fbbd4d3a99259 (MD5) Previous issue date: 2012-07-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The need to implement a software architecture that promotes the development of a SCADA supervisory system for monitoring industrial processes simulated with the flexibility of adding intelligent modules and devices such as CLP, according to the specifications of the problem, it was the motivation for this work. In the present study, we developed an intelligent supervisory system on a simulation of a distillation column modeled with Unisim. Furthermore, OLE Automation was used as communication between the supervisory and simulation software, which, with the use of the database, promoted an architecture both scalable and easy to maintain. Moreover, intelligent modules have been developed for preprocessing, data characteristics extraction, and variables inference. These modules were fundamentally based on the Encog software / A necessidade de desenvolver uma arquitetura de software que promovesse o desenvolvimento de supervis?rio SCADA para monitora??o de processos industriais simulados, com flexibilidade de agregar m?dulos inteligentes e equipamentos como CLP, de acordo com as especifica??es do problema, foi a for?a motriz desse trabalho. No presente estudo foi desenvolvido um supervis?rio inteligente sobre uma simula??o de uma coluna de destila??o modelada no Unisim. Foi utilizado como comunica??o entre o supervis?rio e o software de simula??o o OLE Automation, o qual, junto ao uso de banco de dados, promoveu uma arquitetura de f?cil manuten??o e escal?vel. Foram desenvolvidos ainda m?dulos inteligentes para pr?processamento, extra??o de caracter?sticas dos dados e infer?ncia de vari?veis. Estes m?dulos tiveram como base principal o software Encog
82

IntegraÃÃo de um sistema de recomposiÃÃo automÃtico via OPC para automaÃÃo da rede elÃtrica de distribuiÃÃo em mÃdia tensÃo do campus do Pici da Universidade Federal do Cearà / Integration of an automatic restoration system via OPC to automation of the medium voltage power distribution system of the Pici Campus of the Federal University of CearÃ

LucÃlia Alves dos Santos 29 September 2015 (has links)
Durante muito tempo a manutenÃÃo do sistema de distribuiÃÃo do campus do Pici da Universidade Federal do Cearà - UFC foi de responsabilidade da Companhia EnergÃtica do Cearà â Coelce, pela parceria entre os governos federal e estadual. No entanto, com a privatizaÃÃo da Coelce no ano de 1998, a UFC assumiu essa demanda e por muitos anos, por falta de recursos e planejamento, fez-se apenas intervenÃÃes corretivas emergenciais na infraestrutura existente, resultando em vÃrios problemas na continuidade de suprimento. Felizmente, os Ãltimos gestores atentaram para o problema e muitos investimentos na rede de distribuiÃÃo em mÃdia tensÃo estÃo sendo realizados, visando à modernizaÃÃo e melhoria da seguranÃa, disponibilidade e continuidade do suprimento de energia elÃtrica do campus do Pici. Estas aÃÃes tÃm embasamento tÃcnico nos estudos realizados pelo Departamento de Engenharia ElÃtrica em parceria com o setor de engenharia da UFC (UFC-Infra). Nesse contexto, foi idealizada e està em fase de implantaÃÃo uma subestaÃÃo de 69-13,8 kV, composta de dois transformadores de 5/6,25 MVA, sendo um de reserva, trÃs saÃdas de alimentadores e nove religadores distribuÃdos ao longo da rede de mÃdia tensÃo em 13,8 kV do campus. Este sistema serà operado, supervisionado e controlado por um sistema SCADA (Supervisory Control and Data Aquisition), desenvolvido na plataforma comercial Elipse Power, utilizando o banco de dados Microsoft SQL Server 2012 â versÃo Express. No Ãmbito da automaÃÃo, foi desenvolvida e integrada ao SCADA, via comunicaÃÃo OPC (Open Platform Communications), uma funÃÃo avanÃada denominada, Sistema de RecomposiÃÃo AutomÃtica (SRA-PICI). O SRA-PICI foi desenvolvido em linguagem C#, utilizando o programa Microsoft Visual Studio 2010, modelado em Redes de Petri Coloridas, e testado usando a ferramenta de anÃlise CPN Tools. Para integraÃÃo dos aplicativos SCADA e SRA foi utilizado o protocolo aberto OPC que especifica a comunicaÃÃo de dados em tempo real entre um elemento fonte e um elemento receptor de diferentes fabricantes. Testes de validaÃÃo do SRA e da comunicaÃÃo entre os aplicativos foram realizados em laboratÃrio, que atestam o sucesso da implementaÃÃo e abrem perspectivas importantes para avanÃar na direÃÃo de uma rede elÃtrica inteligente para o campus do Pici. / For a long time the maintenance of the power distribution system of the Pici Campus of the Federal University of Cearà - UFC was the responsibility of the Energy Company of Cearà - Coelce, by the partnership between the federal and state governments. However, with the privatization of Coelce in 1998, the UFC assumed that demand and for many years, due to lack of resources and planning, only the emergency and corrective interventions have taken place, thereby have emerged several problems in continuous supply. Fortunately, the last managers have paid attention to the problem and many investments in the medium voltage distribution network are being carried out, aimed at modernizing and improving security, availability and continuity of energy supply of Pici campus. These actions were based on technical studies conducted by the Department of Electrical Engineering in partnership with the engineering sector of the UFC (UFC-Infra). In this context, was designed and is being implemented a power substation of 69 to 13.8 kV, with two transformers of 5 / 6.25 MVA, , three outputs feeders and nine reclosers distributed throughout the medium voltage distribution network of the campus. This system will be operated, supervised and controlled by a SCADA system (Supervisory Control and Data Acquisition), developed in the commercial platform Elipse Power using the Microsoft SQL Server 2012 database - Express version. In the field of automation, it was developed and integrated into the SCADA via OPC (Open Communications Platform), an advanced function called Automatic Restoration System (ARS-PICI). The ARS-PICI was developed in C # using Microsoft Visual Studio 2010 program, modelled on Colored Petri Nets, and tested using the CPN Tools analysis program. For integration of the SCADA and the ARS application software was used the OPC open protocol that specifies the real time data communication between a source element and a receiving element from different manufacturers. Validation tests of the ARS and communication between the software SCADA-ARS were performed in the laboratory, attesting to the successful implementation and opening important perspectives to advance toward a smart grid to the campus of the Pici.
83

Observabilité et reconstitution d'état des réseaux de distribution du futur / Observability and state reconstitution of the distribution networks of the future

Biserica, Monica Ionela 16 September 2011 (has links)
Dans le futur, les réseaux de distribution deviendront intelligents et actifs et seront utilisés au plus près de leurs limites car l'avènement de la dérégulation avec l'introduction massive de la production décentralisée induira une optimisation des infrastructures de l'énergie pour des besoins environnementaux d'une part, mais aussi par l'introduction de la concurrence dans un secteur autrefois monopolistique. Si on veut utiliser pleinement le potentiel des productions décentralisées dans les réseaux de distribution, on devra rendre ces réseaux observables au moyen de mesures qui seront intégrées dans les systèmes de supervision et de contrôle car sans observabilité et reconstruction d’état du réseau, le contrôle du réseau est impossible. Pour un grand réseau de distribution (quelques milliers de nœuds), avec un taux d’insertion important de productions décentralisées, l’observabilité en temps-réel devient très difficile. Dans la littérature scientifique, on ne trouve pas de travaux prenant en compte les réseaux intelligents et reconfigurables de demain avec production décentralisée massive. L'enjeu du projet sera donc de développer des algorithmes de reconstruction d'état prenant en compte les spécificités des réseaux du futur, à les valider et à les intégrer dans les outils de gestion des réseaux du distributeur. La reconstruction d'état permettra d'aider à l'automatisation et donc à l'introduction d'intelligence dans les réseaux de distribution du futur ainsi qu'à l'insertion massive de productions décentralisées.________________________________________ / In the future, distribution networks will become intelligent and active and will be operated as close as possible to their limits, with the advent of deregulation and with the introduction of mass production that will lead to a decentralized infrastructure, this will guide to an optimization of energy for environmental issues in one side, but also to the introduction of competition in a sector once monopolistic. If the potential of distributed generation in the distribution networks is to be fully exploited, we will make these networks observable through measures which will be integrated into supervision systems and control, because without observability and reconstruction of network status, control network is impossible. For a large distribution network (a few thousand nodes), with an important quantity of distributed generation, real-time observability becomes very difficult. In the scientific literature, there is no work taking into consideration intelligent networks and reconfigurable of the future with decentralized mass power generation. The challenge of the project will be to develop algorithms of reconstruction of the state of the network, taking into account the characteristics of the networks of the future, to validate and integrate them into management tools distribution networks. The reconstruction of the state will assist in the automation and hence the introduction of intelligence in the distribution networks of the future and the insertion massive distributed generation.
84

Návrh propojení a programových modulů pro řízení robotické buňky pro zakládání dílů / Design of interconnections and program modules for robotic cell control for parts creation

Fursov, Ihor January 2019 (has links)
This diploma thesis describes design of interconnections and program modules for robotic cell control for parts creation. Research of this work is focused on industrial comunication protocols. The next part analyzes separate parts of the cell and their ways of connection. Futhermore, control structures of the cell are proposed and after comparison of them SCADA system structure was chosen. Project of connecting separate devices is done in Wonderware Systém Platform. The next step describes procedure of interconection of parts of the cell with each other. Then was designed visualization to operate robotic cell and to illustrate its state. Whole visualization was created using Wonderware InTouch program. In conclusion thesis is reviewed.
85

Správa a automatizace systému vytápění podniku / Management and Automation of Enterprise Facility Heating System

Hartmann, Jiří January 2021 (has links)
The aim of this work is to create a unified control and supervision system, SCADA, for controlling the heating and cooling of the company. The system is controlled by UniPi PLC units. Node-RED is used as control software. The user interface is created by an extension "dashboard". For communication between elements using the MQTT protocol. The InfluxDB database is used for data storage. The Grafana tool is used to visualize historical data. The majority of the created system consists of open software. The system is universal, expandable and it is possible to connect it with another system. The system can be used or adapted to similar problems of advanced heating control.
86

Vätskekylaggregat : Optimering med Advanced Process Control

Rehnholm, Mats January 2020 (has links)
Den pågående globala klimatförändringen innebär att vi behöver minska utsläppen av växthusgaser till atmosfären för att inte äventyra kommande generationers möjlighet att leva på jorden. Där har energieffektivisering blivit allt viktigare för företag för att minska utsläppen av växthusgaser vilket även innebär att man blir konkurrens­kraftig på marknaden.  Genom energieffektivisering minskar man sin förbrukning, vilket också innebär att man spar på förlusterna för transport av energin från produktion till förbrukning, det innebär vinning för miljön, samhäller och företaget. Berendsen är ett företag där effektivisering av sina processer är en ständigt pågående arbete för att spara på miljön och ekonomin. Ett område där det finns förbättringar och besparingar att göra är att undersöka ventilations- och kylsystemet som finns i anläggningen. Kylsystemet används för att kyla tilluften under sommarhalvåret, för att få en bra arbetsmiljö för de anställda. Under den andra halvan av året används kylmaskinen som värmepump för att spara energi. Målet med denna undersökning har varit att besvara frågorna om Advanced process control kan användas för att bestämma om vätskekylaggregatet i ventilationssystemet gör nytta i återvinnings­driften samt om det går att optimera driften av återvinningssystemet. Undersökningen genomfördes med hjälp av linjär regressionsanalys som är ett av flera verktyg i APC. Vidare har studien visat att verktyget i APC är användbar för att optimera driften av en process. / The ongoing global climate change means that we need to reduce greenhouse gas emissions to the atmosphere in order not to jeopardize the ability of future generations to live on earth. There, energy efficiency has become increasingly important for companies to reduce greenhouse gas emissions, which also means becoming competitive in the market. By improving energy efficiency, you reduce your energy consumption, which also means saving on the loss of energy transport from the product to the consumer, which means benefits for the environment, communities and the company. Berendsen is a company in which the efficiency of its processes is an ongoing work to save the environment and the economy. One area where there are improvements and savings to be made is to investigate the ventilation and cooling system that is in the plant. The liquid cooling unit is used to cool the supply air during the summer months, to provide a good working environment for the employees. During the second half of the year, the cooling machine is used as a heat pump to save energy. The aim of this study has been to answer the questions if Advanced process control can be used to determine whether the liquid cooling unit in the ventilation system is useful in the recovery operation and whether it is possible to optimize the operation of the recycling system. The study was conducted using linear regression analysis, which is one of several tools in APC. Furthermore, the study has shown that the tool in APC is useful for optimizing the operation of a process
87

Automatic wind turbine operation analysis through neural networks / Automatisk driftanalys av vindturbiner medels neurala nätverk

Boley, Alexander January 2017 (has links)
This master thesis handles the development of an automatic benchmarking program for wind turbines and the thesis works as the theoretical basis for this program. The program is created at the request of the power company OX2 who wanted this potential to be investigated. The mission given by the company is to: 1. to find a good key point indicator for the efficiency of a wind turbine, 2. to find an efficient way to assess this and 3. to write a program that does this automatically and continuously. The thesis determines with a study of previous research that the best method to utilize for these kinds of continuous analyses are artificial neural networks which can train themselves on historical data and then assess if the wind turbine is working better or worse than it should with regards to its history. This comparison between the neural network predicted operation and the actual operation works as the measurement of the efficiency, the key point indicator for how the turbine work compared to how it historically should operate. The program is based on this principle and is completely written in MATLAB. Further testing of the program found that the best variables to use are wind speed and the blade pitch angle as input variables for the neural network and active power as the target used as the variable to predict and assess the operation. The final program was able to be fully automated and integrated into the OX2 system thanks to the possibility to continuously import wind turbine data through APIs. In the final testing was the program able to identify 75% of the anomalies manually found in the half year and in the five turbines used for this thesis, the small anomalies not found manually but identified by the program excluded. / Den här masteruppsatsen hanterar utvecklandet av ett automatiskt driftanalyseringsprogram för vindkraftverk och fungerar som det teoretiska underlaget för detta program. Programmet utvecklades på uppdrag av kraftbolaget OX2 som ville undersöka potentialen för ett sådant analysprogram i deras verksamhet. Uppdraget givet var att: 1. ta fram en bra indikator när det gäller den faktiska effektiviteten av ett vindkraftverk, 2. att hitta ett effektivt sätt att använda detta måttet i en analys där målet är att hitta avvikelser, och 3. skriva ett program som automatiskt kan använda måttet och metoden över tiden. Rapporten kommer via litteraturstudie fram till att tidigare forskning visar på att neurala nätverk är den mest lovande metoden för att genomföra sådan här analys. Dessa nätverk kan träna sig själva på historiska data och sedan analysera om vindturbinen arbetar bättre eller sämre än historiskt. Den här jämförelsen mellan den historiskt grundade förutspådda kraften ut och den faktiska kraften ut fungerar som kvalitetsmåttet på hur bra turbinen fungerar. Programmet är baserat på den här principen och är helt skriven i MATLAB. Vidare tester av programmet visar att de bästa variablerna att använda för att förutspå kraften ut är vindhastigheten och bladens vinkel mot vinden. Slutprogrammet var kapabelt att fullt automatiskt och integrerat i OX2s system identifiera 75% av alla avvikelser som manuellt hittats i ett halvårs data på de fem turbinerna använda för rapporten, småfel hittade av programmet men inte manuellt exkluderat.
88

Wide area monitoring and control systems - application communication requirements and simulation

Chenine, Moustafa January 2009 (has links)
<p>Today’s electrical transmission & distribution systems, are facing a number of challenges related to changing environmental, technical and business factors. Among these factors are, increased environmental restrictions leading to higher share of production from renewable and uncontrollable sources as well as local environmental concerns regarding construction of new transmission and distribution lines. The re-regulation of the electricity market has created a dynamic environment in which multiple organizations have to coordinate and cooperate in the operation and control of the power system. Finally, the high rate of devel-opment within the ICT field is creating many new opportunities for power system opera-tion and control, thanks to introduction of new technologies for measurement, communi-cation and automation.</p><p>As a result of these factors, Wide Area Monitoring and Control (WAMC) systems have been proposed. WAMC systems utilize new ICT based technologies to offer more accurate and timely data on the state of the power system. WAMC systems utilize Phasor Measure-ment Units (PMUs) that have higher data rates and are time synchronised using, GPS satel-lites. This allows synchronized observation of the dynamics of the power system, making it possible to manage the system at a more efficient and responsive level and apply wide area control and protection schemes. The success WAMC systems, on the other hand, are largely dependent on the performance of the Information and Communication Technology (ICT) infrastructure that would support them.</p><p>This thesis investigates the requirements on, and suitability of the ICT systems that support WAMC systems. This was done by identifying WAMC applications and the elicitation of their requirements. Furthermore, a set of simulation projects were carried out to determine the communication system characteristics such as delay and the impact of this delay on the WAMC system.</p><p>This thesis has several contributions. First, it provides summary and analysis of WAMC application priorities and requirements in the Nordic region. Secondly it provides simula-tion based comparison and evaluation of communication paradigms for WAMC systems. The research documented in this thesis addresses these paradigms by providing a compari-son and evaluation through simulation. Thirdly, the thesis provides insight to the possible sources of delay in WAMC architecture and the impact of these delays on data quality specifically data incompleteness. This provides insight on what applications are important to practitioners and what is the expected performance of these applications, as seen from the power system control and operation point of view.</p>
89

A latency comparison of IoT protocols in MES

Lindén, Erik January 2017 (has links)
Many industries are now moving several of their processes into the cloud computing sphere. One important process is to collect machine data in an effective way. Moving signal collection processes to the cloud instead of on premise raises many questions about performance, scalability, security and cost.This thesis focuses on some of the market leading and cutting edge protocols appropriate for industrial production data collection. It investigates and compares the pros and cons of the protocols with respect to the demands of industrial systems. The thesis also presents examples of how the protocols can be used to collect data all the way to a higher-level system such as ERP or MES.The protocols focused on are MQTT and AMQP (in OPC-UA). The possibilities of OPC-UA in cloud computing is of extra interest to investigate in this thesis due to its increasing usage and development.
90

Plataforma de Comunicaciones para la complementación del sistema scada en los centros de control de operaciones de las empresas de distribución eléctrica Norte-Centro

Rojas Rosales, Luis Enrique January 2012 (has links)
El presente documento es el resultado de la ejecución del Proyecto “Implementación del Sistema SCADA en los Centros de Control de Operaciones de las Empresas Eléctricas del Norte – Centro”, Obra “Plataforma de Comunicaciones para el Sistema SCADA” realizada en el área de concesión de las empresas eléctricas: HIDRANDINA S.A., ELECTRONOROESTE S.A., ELECTRONORTE S.A. Y ELECTROCENTRO S.A., que permita transmitir la información del sistema de teleprotección, del sistema SCADA y del sistema de telefonía privada en tiempo real hacía el COES – SEIN y los Centros de Control. El contenido de este proyecto incluye los requisitos indispensables para implementar un SCADA en Distribuidoras Eléctricas que parten de la Concepción y Alcances, Sedes de las DD.EE., Normas de un SCADA, Estándares aplicados, Descripción de los Sistemas Eléctricos de las DD.EE., Sistemas de Información Existentes, Contadores, Relés, Subestaciones a ser Supervisadas, Desempeño, Tiempos de Respuesta, Disponibilidad del Sistema, Requisitos Generales del SCADA, Requisitos de Adquisición de Datos, Protocolos de Comunicación, Procesamientos de Datos, Códigos de Calidad, Registro de Secuenciador de Eventos, Colocación de Etiquetas, Procesamiento de Alarmas, Coloreado de la Red, Interfaz Gráfica con el Usuario, Reportes, Seguridad de la Base de Datos, Requisitos de Hardware, Requisitos de Software, Requisitos de los Concentradores de Datos, Tipos de Entradas y Salidas Lógicas, Almacenamiento, Comunicación de Datos, Algoritmos, Integración con IED´s, Sistemas de Comunicaciones, Enlaces Vía Fibra Óptica, Enlaces Inalámbricos y Enlaces Vía Onda Portadora. Se concluye que el presente proyecto es integral, debido a que involucra la implementación del Sistema SCADA y la plataforma de Comunicaciones con nivel de confiabilidad al 99.8% para transportar la información de las subestaciones eléctricas hacía los Centros de Control y COES – SEIN que monitorea las operaciones en tiempo real. Debido a que las cuatro empresas eléctricas antes mencionadas tienen áreas de concesiones muy extensas, el presente trabajo se limita a exponer la implementación del SCADA y Plataforma de Comunicaciones de la empresa eléctrica ELECTROCENTRO S.A., cuya sede principal se encuentra en la ciudad de Huancayo.

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