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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.
21

Implementação do modbus para aplicações de sistemas de controle via rede sem fio / Implementation and evaluation of wireless networked control using modbus

Caldiéri, Marcos Rogério [UNESP] 21 October 2016 (has links)
Submitted by Marcos Rogerio Caldieri null (mrcaldieri@gmail.com) on 2016-12-14T23:11:29Z No. of bitstreams: 1 Marcos-Mestrado.pdf: 2168690 bytes, checksum: 11f237fc5587a57486d006c939b576af (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-12-19T17:40:14Z (GMT) No. of bitstreams: 1 caldieri_mr_me_bauru.pdf: 2168690 bytes, checksum: 11f237fc5587a57486d006c939b576af (MD5) / Made available in DSpace on 2016-12-19T17:40:14Z (GMT). No. of bitstreams: 1 caldieri_mr_me_bauru.pdf: 2168690 bytes, checksum: 11f237fc5587a57486d006c939b576af (MD5) Previous issue date: 2016-10-21 / A recente introdução de transmissores sem fio na indústria provocou um novo interesse em técnicas de medição e controle, porém a maioria das aplicações está restrita a medições de variáveis de processo em malha aberta ou aplicações de monitoramento. O motivo é a falta de confiabilidade devido aos problemas inerentes ao meio de transmissão, que pode ser a perda de pacotes de informação, atrasos de comunicação variantes no tempo, atualização muito lenta e não periódica da medição e vários tipos de interferências. A maior parte dos controladores industriais em controle de processos assumem que o ciclo de controle é executado de forma periódica e que uma nova medição está disponível para ser usada em intervalos de tempo conhecidos. No entanto esta situação não pode ser garantida quando sensores ou transmissores sem fio são usados em aplicações de controle em malha fechada, denominadas de Sistemas de Controle via Redes sem fio (WNCS – Wireless Networked Control Systems). Nesses tipos de aplicações, os transmissores sem fio devem transmitir novas medições de forma não periódica e somente se a medição da variável do processo tiver alterado significativamente. Para tornar esta tecnologia de WNCS mais confiável, muitas técnicas de controle têm sido pesquisadas, entre elas o PIDPlus que representa uma modificação do algoritmo PID para controle via rede sem fio. Este trabalho apresenta a implementação do protocolo Modbus para aplicações de WNCS. O protocolo Modbus TCP foi embarcado em hardware dedicado viabilizando a transmissão de dados via Ethernet TCP/IP e Wi-Fi. Uma comparação e avaliação de controladores PID para aplicação em WNCS sob condições de amostragem e atrasos de comunicações variáveis e de perdas de transmissão de mensagens foi realizada. Os resultados são analisados do ponto de vista de desempenho de controle e robustez. Resultados experimentais numa planta piloto comprovam a eficiência da implementação de uma malha de controle sem fio usando uma rede Wi-Fi com o protocolo Modbus embarcado e um controlador PIDPlus. / The recent introduction of wireless transmitters in the industry has driven a new interest in measuring and control techniques, but most applications are restricted to measurements of process variables in open loop or monitoring applications. The reason is the lack of reliability due to problems inherent to the transmission medium, which may be the packet loss, time varying delay, slow and aperiodic measurement updates and interference. Most industrial process controllers assume that the control cycle is performed periodically and that a new measurement is available to be used at known time intervals. However it cannot be guaranteed when wireless sensors or transmitters are used in closed loop control applications, called Wireless Networked Control Systems (WNCS). In these type of applications, wireless transmitters shall transmit new measurements not periodically and only if the process variable measurement has changed significantly. In order to enable and make this WNCS technology reliable, many control techniques have been researched including the PIDPlus that is a modified PID algorithm for wireless control. This paper presents the implementation of the Modbus protocol for WNCS applications. The Modbus TCP was embedded in dedicated hardware enabling the transmission of data via Ethernet TCP/IP and Wi-Fi. A comparison and evaluation of PID controllers for WNCS were done considering situations of variable sampling and communication delays and packet losses. The results are analyzed from the point of view of control performance and robustness. Experimental results in a pilot plant prove the efficiency of the implementation of a wireless control loop using a Wi-Fi network with embedded Modbus protocol and PIDPlus controller.
22

Improving system integration by standardizing and automating the Modbus protocol

Ågren, David January 2020 (has links)
Communicating devices are on the rise. Fueled by the introduction of Internet-of-Thing (IoT) and Industry 4.0, more and more devices are capable of information sharing. There is a long history of communicating devices in industrial and building management contexts that previously relied on fieldbuses. One of these legacy fieldbuses is the Modbus protocol, originating in serial communication and now adapted for use with Ethernet. It has significant adoption in the fields of industrial automation systems (IAS) and building management systems (BMS) but carries many limitations. Industrial systems often have a long lifespan and fundamental changes are not introduced quickly. This leads to a need for legacy communication protocols to be able to function alongside the new paradigms for the foreseeable future. In order to facilitate this phase, an attempt to improve system integration in the Modbus context is performed in this thesis. By utilizing standardization and automation principles, additional functionality and definitions are proposed to the Modbus protocol to help improve system integration. By using interviews with system integrators and document reviews of available Modbus description documents three iterative development processes are performed to answer the research questions.  A proposed data model is presented, allowing for a standardized way to represent the contents of a Modbus register. Its attributes are clearly defined with descriptions and constraints. A new function code specification (0x47) is defined and presented in the same form as other function codes are described in the current Modbus specification. It allows for Modbus descriptors to be retrieved directly from the slave device. As a proof-of-concept the function code is developed in an existing Modbus implementation (Modbus4J). A client application is created to allow for fully functional demonstrations for a broader audience. The resulting communication is captured in Wireshark and presented as proof-of-concept.
23

Modbuskommunikation mellan PLC och växelriktare : Hantering av register och implementeringsmöjligheter / Modbus communication between PLC and inverter : How to handle registers and possible implementations

Råberg, Andreas January 2020 (has links)
Mätning av elproduktion i solcellsparker och i större installationer sker vanligtvis med separata elmätare inbyggda i respektive växelriktare eller med externa elmätare för grupper av växelriktare. I större installationer kan det även förekomma växelriktare med olika märken. Lösningar för att sammanställa elproduktionsdata från olika växelriktare och märken är ofta kostsamma, vilket har skapat behov av att sammanställa elproduktionsdata på ett effektivare sätt och med färre apparater. Utöver elproduktion finns även en stor mängd data tillgänglig i en växelriktare som kan vara användbar vid driftövervakning och utvärdering av prestanda. I samarbete mellan Karlstads universitet och Rejlers i Göteborg undersöktes möjligheten att använda en PLC (Programmable Logic Controller) för att sammanställa data från en växelriktare. Både PLC och de flesta växelriktare använder Modbus® som protokoll för att kommunicera med andra apparater. Målet med projektet var att skapa en fungerande kommunikation mellan vald PLC och växelriktare för att hämta driftdata från växelriktaren och antingen spara informationen som Rejlers IT division Embriq kan hämta eller skicka direkt till Embriq. I projektet upprättades kommunikation mellan PLC och växelriktare via Modbusprotokollet där vald PLC klarade av att hämta och sammanställa information från vald växelriktare. PLC:n hade även begränsningar som försvårade hanteringen av hämtade driftdata och sändning till Embriq. Rapporten ger förslag på hur hämtade driftdata kan hanteras i PLC:n och alternativ till säker överföring till Embriq. (Modbus® is a registered trademark of Schneider Electric, licensed to the Modbus Organization, Inc.) / Measurement of electricity production in solar parks and in larger installations is usually done with separate electricity meters built into each inverter or with external electricity meters for groups of inverters. In larger installations there may also be inverters with different brands. Solutions for compiling electricity production data from different inverters and brands are often costly, which has created the need to compile electricity production data more efficiently and with fewer devices. In addition to electricity production, a large amount of data is also available in an inverter that can be useful in operation monitoring and performance evaluation. In collaboration between Karlstad University and Rejlers in Gothenburg, the possibility of using a PLC (Programmable Logic Controller) was explored to compile data from an inverter. Both PLC and most inverters use the Modbus® protocol to communicate with other devices. The objective of the project was to create a working communication between the selected PLC and inverter to retrieve operating data from the inverter and either save the information that Rejlers IT division Embriq can retrieve or send directly to Embriq. In the project, communication was established between PLC and inverter via the Modbus protocol where the selected PLC was able to retrieve and compile information from the selected inverter. The PLC also had limitations that made it difficult to handle retrieved operating data and transmission to Embriq. The report provides suggestions on how retrieved operational data can be handled in the PLC and alternatives for secure transfer to Embriq. (Modbus® is a registered trademark of Schneider Electric, licensed to the Modbus Organization, Inc.)
24

Systém pro alokaci a konfiguraci hardwarových zdrojů / System for Allocation and Configuration of Hardware Resources

Slováček, Jan January 2018 (has links)
This master's thesis is about analysis, design and implementation of a system for shared resources reservation and its remote control. Subjects of sharing are test and development prototypes. For remote control are used I/O devices ET-7042 and SITOP PSU8600. The reader is introduced to target environment, REST application interfaces and communication standards Modbus and Profinet. The knowledge gathered is used in design and implementation of the system. The main goal of thesis is to make development and testing in lab more effective.
25

GSM brána pro PLC systémy / GSM gate for PLC systems

Kadaňka, Karel January 2019 (has links)
The master´s thesis describes the initial design of communication module for industrial automation purposes which can transmit short status messages via the GSM network informing about the status of the connected device to a predefined telephone number. In the first part, the communication protocols are describe and a market survey is carried out. Then follows the evaluation of the market survey and the justification of construction of the device. The following chapters are devoted to the description of the device being developed, its individual components and program description and testing prototype.
26

Vhodná strategie pro detekci bezpečnostních incidentů v průmyslových sítích / Appropriate strategy for security incident detection in industrial networks

Kuchař, Karel January 2020 (has links)
This diploma thesis is focused on problematics of the industrial networks and offered security by the industrial protocols. The goal of this thesis is to create specific methods for detection of security incidents. This thesis is mainly focused on protocols Modbus/TCP and DNP3. In the theoretical part, the industrial protocols are described, there are defined vectors of attacks and is described security of each protocol. The practical part is focused on the description and simulation of security incidents. Based on the data gathered from the simulations, there are identified threats by the introduced detection methods. These methods are using for detecting the security incident an abnormality in the network traffic by created formulas or machine learning. Designed methods are implemented to IDS (Intrusion Detection System) of the system Zeek. With the designed methods, it is possible to detect selected security incidents in the destination workstation.
27

Automatizovaný tester bezpečnosti chytrých zařízení v energetice / Automated cyber security tester for smart devices in industry

Dávidík, Roland January 2020 (has links)
This diploma thesis explains the principle of SCADA systems and describes the DLMS/COSEM protocol. In the next part, it shortly describes the Modbus protocol and details the pros and cons of the Modbus protocol in comparison with the DLMS/COSEM protocol. In the next part, an open-source automated scanner was created. This scanner detects devices in a laboratory network. As the next step, the automated scanner finds out open ports and active services, which run on these devices, and tries to attack HTTP, SSH, and Telnet services. Next, the program checks, whether the found device is a smart-meter device and if it is compatible with DLMS/COSEM protocol. If yes, it checks, if the service is vulnerable to DOS attack and breaker disconnection. Scanner’s findings are presented in a newly created web application. NMAP, Masscan, and Metasploit open-source programs are used in the automated scanner. The whole automated scanner is optimized for the HW device Raspberry Pi with the operating system Raspbian Buster Lite installed. This work also describes the testing of the scanner on the laboratory environment and the results are evaluated afterwards.
28

Experimentální aplikace robotické paže využívající průmyslové komunikační protokoly / Experimental application of robotic arm using industrial communication protocols

Kohoutek, Tomáš January 2020 (has links)
This diploma thesis is focused on the analysis of the most well-known industrial protocols and acquaintance with the Dobot Magician robotic arm. The main goal of this thesis is to create an industrial loop, which consists of communication – client and server. The individual components of the industrial loop consist of three robotic arms (including peripherals), their control units (in our case Raspberry PI 3B +), switch, and a server. The control units communicate with the server using two selected industrial protocols, namely Modbus TCP and EtherNET/IP. The result of the work is an endless loop, which tries to resemble the real operation of the assembly and disassembly of the box equipped with dierent items.
29

Inteligentní převodník Ni odporových senzorů s rozhraním Ethernet / Ni sensors to Ethernet convertor

Kubíček, Ondřej January 2010 (has links)
This work deals with hardware and software solution for the temperature converter of the standard rezistance temperature Ni sensors with the output through the Ethernet, driven by the Rabbit microcontroller. First part of this thesis deals with the theory of the temperature measurement. There are introduced basic principles of the temperature sensors. In the next part of the work are introduced communication standard and application protocol Modbus. The rest of the work deals with the hardware concept of the converter, the control program of the converter and the program developed for the PC.
30

Univerzální řídicí jednotka pro testování životnosti motorů / Universal control unit for life test of motors

Ševčík, Šimon January 2016 (has links)
This thesis describes theway of BPM motors control and its use in life testing. Firstly it describes the properties of motors and their differences. Secondly it describes possibilities of motor control and their need for life testing. Finally it describes proposal of the universal control unit, types of controling, programming part and technical documentations.

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