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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.
51

Contribution à la modélisation du réseau électrique domestique en vue de la caractérisation du canal de propagation CPL / Contribution to the indoor power line grid modeling to characterize the PLC propagation channels

Guezgouz, Djamel 13 December 2010 (has links)
Le réseau électrique s'utilise aujourd'hui comme support de transmission des signaux Ethernet. C’est le concept des courants porteurs en ligne. Cette technique de transmission permet d’obtenir des débits supérieurs au Wifi. Cependant, la complexité des réseaux électriques et l'environnement électromagnétique domestique peuvent dégrader les performances de cette technologie. L’environnement électrique de l'habitat avec ses appareils électroménagers divers en font un milieu difficilement maitrisable. L’objectif est d’appréhender et de modéliser cet environnement et le comportement des équipements qui y sont déployés. Pour cela, ce mémoire présente plusieurs méthodes pour modéliser les lignes électriques dans l'habitat. Les modélisations existantes sont difficilement généralisables à un réseau électrique quelconque. Nous proposons une modélisation de type circuit électrique.Son intérêt réside dans la simplicité de l'outil de simulation d'un réseau électrique, réalisé parla mise en cascade de plusieurs blocs intégrés à la librairie SPICE. Les blocs SPICE proposés prennent en compte la dépendance fréquentielle des paramètres des quadripôles. Une étape de caractérisation expérimentale est développée pour implémenter ces blocs. Un réseau expérimental de test, constitué de différentes technologies de câble, a été caractérisé en termes de bruit, d'impédance et de pertes d'insertion. Le rayonnement émis lors d'une transmission CPL a également été mesuré. / The power line grid is used for data transmission by means of the broad band powerline communication systems (BPLC) The main advantage of this technology consists in providing an existing infrastructure of wires and wall sockets that are easy to access throughout a building and offering physical data rates comparable with other existing communication technologies such as Wi-Fi. Nevertheless, the power line grid complexity, the various connected household appliances and the housing electromagnetic environment,impact the PLC transmission performances. As results the housing environment is not a controllable medium. The objective of the current thesis is to study the electromagnetic environment of the Indoor power line network, and to model the potential impacts of both the power line grid topology and the household devices on the PLC physical layer. The existing modeling approaches require a deduction of theirs parameters from the measurements and cannot be generally applied. We propose a new model based on circuitry approach. Its main interest consists in the simplicity of the simulation tool of power line grid which is based on series symmetric SPICE circuit integrated to SPICE library. To this aim, the characterization of the power cable, of the electrical accessories and household devices is necessary. The impedance of powered household devices is measured according to simple measurement protocol. The proposed model takes into account the variation of the whole primary parameters of the electrical cable as function of frequency. An experimental characterizationof the so called PLC READY test bench was carried out in terms of noise, impedance and insertion loss. The radiated electromagnetic field during a PLC communication is measured.
52

Design, modelling and control of a brachiating power line inspection robot

Patel, Javaad January 2016 (has links)
The inspection of power lines and associated hardware is vital to ensuring the reliability of the transmission and distribution network. The repetitive nature of the inspection tasks present a unique opportunity for the introduction of robotic platforms, which offer the ability to perform more systematic and detailed inspection than traditional methods. This lends itself to improved asset management automation, cost-effectiveness and safety for the operating crew. This dissertation presents the development of a prototype industrial brachiating robot. The robot is mechanically simple and capable of dynamically negotiating obstacles by brachiating. This is an improvement over current robotic platforms, which employ slow, high power static schemes for obstacle negotiation. Mathematical models of the robot were derived to understand the underlying dynamics of the system. These models were then used in the generation of optimal trajectories, using nonlinear optimisation techniques, for brachiating past line hardware. A physical robot was designed and manufactured to validate the brachiation manoeuvre. The robot was designed following classic mechanical design principles, with emphasis on functional design and robustness. System identification was used to capture the plant uncertainty and a feedback controller was designed to track the reference trajectory allowing for energy optimal brachiation swings. Finally, the robot was tested, starting with sub-system testing and ending with testing of a brachiation manoeuvre proving the prospective viability of the robot in an industrial environment.
53

Detekcia prechodu nulou pre účely synchronizácie hodín v prostredí PLC komunikácie / Zero-Cross Detection for Time Synchronization in the Environment of PLC Communication

Šťastný, Ladislav January 2018 (has links)
The doctoral thesis proposes a synchronization event detection method suitable for establishing a common time base across devices using power-line communication. The technique facilitates the creation of a synchronization procedure for smart grid terminal devices, thus bringing to the low-voltage segment new functionalities already known from the higher voltage levels of the distribution network. High-precision, zero-cross line voltage detection was employed as the synchronization event. The use of the PLL (phase-locked loop) was considered and analyzed as a potentially applicable option; however, such a solution proved to be insufficiently robust against interference. Further, an FFT-based approach was designed and reviewed. The technique performs zero-cross detection, but only for the fundamental harmonic component that remains the same across the entire network. The influence of incoherent sampling on the FFT, too, was tested during the development of the method; in this context, coherent sampling was found to constitute an essential prerequisite for accurate detection as it allows us to eliminate the spectral leakage error. The impact of an AD converter on the detection accuracy was also evaluated. The proposed approach ensures the accuracy required for all common measurements and operations to improve the production, distribution, and consumption of electricity through smart grids.
54

Powerline komunikace pro řízení LED světel / PowerLine Communication for LED unit control

Šebesta, Ondřej January 2020 (has links)
This diploma thesis deals with the design and testing of a system for powerline communication, enabling control of LED lights. The work first describes the basic principles of powerline communication, specifies the communication bands and summarizes the basic functional requirements for communication within the system for LED lighting control. It also describes the method of selecting a modem for powerline communication, the design of a test module with this modem and also the method of testing real communication between two test modules, including test results. The most comprehensive part of the work describes the design of hardware and software of the universal PLC module and how to use it. In addition, it referes to the development tools used as an example of implementation in LED lighting. At the end of the work are summarized the results of testing the proposed system.
55

Network Voice Message Box / Network Voice Message Box

Dítě, Miroslav January 2009 (has links)
In this Master's thesis a power line communication is shortly described and the scheme of the communication system is realized. The communication device is called NVMB. This abbreviation means Network Voice Message Box. It should be used for transfer of the voice message via power line. It enables its recording, playback and sending. A process of the scheme design is created, functionality of the device is realized and reviewed in the main part of the Master's thesis. The other chapter of the thesis is devoted to the software communication system.
56

Návrh a realizace domácí sítě LAN technologií PLC / Design and implementation of LAN home network using PLC technology

Pataj, Jiří January 2010 (has links)
Master’s thesis deals with possibilities of data communication on low voltage power lines, so-called PLC. This technology allows data transfer on power lines. According frequency band the PLC can be subdivide into narrowband or broadband class. Given are theoretical knowledge’s of data communication on power lines and describes technical solutions. Consequently is suggestion of LAN, which is accessible for commercial usage made by DS2 and his suitable for home use. The main acquisition is implementing and measuring this experimentally created LAN in family house. The results are real bitrates depending on distance and quality of specific connection.
57

Datová komunikace v distribučních systémech / Data communication in distribution systems

Sirotný, Miroslav January 2011 (has links)
This project includes a basic overview of concepts as is communication, data communication and distributed to systems. Further focuses on the technology use for remote data collection. Part is dedicated PLC technologies, which use systems for remote data collection. The thesis is also mentioned the concept of quality of electrical energy and standard ČSN EN 50160. The main part is focused on the design, implementation and measurement of the PLC network.
58

Senzorická síť po silových rozvodech / Sensor network over power line systems

Plachý, Martin January 2012 (has links)
This semestral thesis contains information about a construction of a senzor network over power line systems. Those are divided with the reference to bandwidth. After the general description of the network there is the whole realisation of a drive unit and a sensor unit described and the design of data and power circuits is solved separately. The description of both units programs written in the ANSI C language is presented in the next chapter. The description of the network control by PC and a quantitative evaluation of the network reliability are also included.
59

Generátor přenosových funkcí silnoproudých vedení / Power line transfer function generator

Šenk, Marek January 2013 (has links)
The aim of this thesis is to create a power line transfer function generator in Matlab. Work on introduction explains the concept of power line and describes the different types of topologies and types of cables that power line are the most widely used today. It is also discussed PLC technology, its structure, characteristics of the transmission channel and interferences. The following are approach the types of the modeling of power line. More details are described generally modeling in the frequency (two-port network model), which is used in the created generator. The next section provides a power line model, whose principle is used in the generator. The following is a description of created the generator and comparison with FTW PLC Simulator. In conclusion, the thesis presents the results of simulations the transfer function, which show the magnitude and phase frequency characteristics of different topologies and parameters.
60

Simulátor přenosových funkcí silnoproudého vedení / Power line channel simulator

Jedlička, Tomáš January 2014 (has links)
The master’s thesis is focused on the analysis and modeling of power line communication with aim to implement power line channel simulator in the programming environment Matlab. At the beginning of the thesis are summarized basic information about the PLC communication, its basic distribution in terms of frequency bands and are also mentioned advantages and disadvantages. The emphasis on the meaning and importance of modeling with the aim to analyze PLC communication channel is specified further. The following is a detailed description of the current power lines communication models. Power line channel simulator was created on the basis of mathematical analysis for low-voltage (LV) distribution networks. The created simulator uses a model of cascaded two-ports and works in random or fixed mode. Input parameters are real topologies, different types of loads and cables. RLC resonant circuit as a frequency selective impedance is also included in impedance models. Based on the obtained results was performed the analysis, determined the critical parameters and extreme values. Comparison of effectiveness of created simulator was processed on the basis of available simulators from other authors. Two versions of simulator were created using the results obtained under comparison of effectiveness. For comparison was also performed real measurement on a simple topology. The experimental measurements results have been implemented in the simulator.

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