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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.
101

Measurement and characterization of aircraft PLC channels

Camponogara, Ândrei 19 August 2016 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-07-21T13:33:19Z No. of bitstreams: 1 andreicamponogara.pdf: 136426958 bytes, checksum: 46cc006b7976ec02d48cf7b3ce754288 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-08-09T13:17:24Z (GMT) No. of bitstreams: 1 andreicamponogara.pdf: 136426958 bytes, checksum: 46cc006b7976ec02d48cf7b3ce754288 (MD5) / Made available in DSpace on 2017-08-09T13:17:24Z (GMT). No. of bitstreams: 1 andreicamponogara.pdf: 136426958 bytes, checksum: 46cc006b7976ec02d48cf7b3ce754288 (MD5) Previous issue date: 2016-08-19 / Esta dissertação tem como objetivo discutir a caracterização da rede de energia elétrica que alimenta os equipamentos de instrumentação de uma aeronave de ensaios de voo. Para a caracterização desses canais, uma campanha de medição foi realizada dentro da aeronave, de forma que dois arranjos de cabos foram adotados. Um representa a topologia em árvore, típica em aeronaves, enquanto que o segundo refere-se a uma proposta, a qual tem por objetivo compensar os problemas causados pelo modo comum através da redução do efeito de multi-percurso. No intuito de auxiliar o desenvolvimento das novas gerações de tecnologia de comunicação via rede de energia elétrica (power line communication -PLC) para aeronave e levando em conta o padrão aeronáutico RTCA/DO-160G, análises dos canais PLC medidos são realizadas em termos de ganho médio do canal, raiz quadrada do atraso médio de propagação, tempo de coerência, banda de coerência e capacidade do canal. Em relação ao ruído aditivo medido, análises da densidade espectral de potência e informações estatísticas são descritas. Além disso, distribuições de probabilidade são consideradas para modelá-lo e parâmetros do ruído impulsivo são discutidos. Em seguida, análises da impedância de acesso mostram importantes características dos cabos de ener-gia elétrica utilizados para alimentar os equipamentos de instrumentação da aeronave de ensaios de voo. Por fim, comparações entre os canais PLC medidos em residências Brasilei-ras mostram que a tecnologia PLC disponível no mercado (desenvolvida para residências) é útil para aplicações em aeronave. / This dissertation aims to discuss the characterization of the flight test aircraft power line channels related to the 28 Vdc electric power grids designed to supply energy to the in-strumentation equipments. For characterizing these channels, a measurement campaign was carried out aboard an aircraft and two data communication configurations of power lines were taken into account. While one represents a typical aircraft tree-shape topology of cable bundles, the second one is a proposal aiming at compensating the common-mode problems by reducing the multipath effects. In the light of aeronautic standard RTCA/DO-160G, analyses of measured power line communication (PLC) channels in terms of average channel gain, root mean square - delay spread, coherence time, coher-ence bandwidth, and channel capacity gives some directions to design novel generations of PLC technology for aircraft applications. Regarding the measured additive noises, anal-yses based on power spectral density and evaluated statistic information are addressed. Moreover, symmetric statistical distributions are considered to model the measured addi-tive noise. In addition, parameters of impulsive presence in the measured additive noise are discussed, and analysis of the access impedance shows some important characteristics of typical power lines used to supply energy to instrumentation equipments in a flight test aircraft. Finally, a comparison with the Brazilian in-home PLC channels shows that the PLC technology on-the-shelf (designed for in-home PLC) is also useful for aircraft applications.
102

A prototype of a narrowband hybrid PLC/Wireless transceiver

Costa, Vinícius Lagrota Rodrigues da 15 December 2017 (has links)
Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-03-23T12:51:48Z No. of bitstreams: 1 vinciuslagrotarodriguesdacosta.pdf: 1396401 bytes, checksum: cb024a49d0816c8df51709de3243f9be (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-03-23T13:03:30Z (GMT) No. of bitstreams: 1 vinciuslagrotarodriguesdacosta.pdf: 1396401 bytes, checksum: cb024a49d0816c8df51709de3243f9be (MD5) / Made available in DSpace on 2018-03-23T13:03:30Z (GMT). No. of bitstreams: 1 vinciuslagrotarodriguesdacosta.pdf: 1396401 bytes, checksum: cb024a49d0816c8df51709de3243f9be (MD5) Previous issue date: 2017-12-15 / Esta dissertação descreve o protótipo de um transceptor banda estreita (narrowband - NB) hybrid power line communication (PLC)/Wireless (NB hybrid PLC/Wireless), o qual utiliza a rede de energia elétrica e o ar, em paralelo, para transmissão de dados, visando aplicações de redes inteligentes (smart grid - SG) e Internet das Coisas (Internet of Things - IoT). Nesse protótipo é introduzida uma versão aprimorada e adaptada do padrão IEEE 1901.2, contemplando a subcamada de controle de acesso ao meio (medium access control - MAC) e da camada física (physical - PHY) para transmissão de dados por ambos os meios de comunicação. O aprimoramento é baseado no uso da transformada de Hilbert para a recuperação da informação em quadratura em ambos os canais, possibilitando a estimação do desvio de frequência entre os clocks do transmissor e do receptor. Uma das adaptações no padrão IEEE 1901.2 é a introdução do protocolo de roteamento, o qual possibilita o transceptor a se comunicar com nós a dois ou mais saltos de distância entre eles. A outra adaptação é a implementação de uma técnica de correção de pacotes com erro a nível de camada de enlace, a qual combina os pacotes com erros recebidos pelas interfaces PLC e/ou wireless e corrige-os, dentro de uma certa capacidade. Importante ressaltar que o transceptor NB hybrid PLC/Wireless é capaz de interoperar com o transceptor NB PLC baseados no padrão IEEE 1901.2. O protótipo do transceptor NB hybrid PLC/Wireless é implementado usando um dispositivo field-programmable gate array (FPGA) usando uma linguagem descritiva de hardware (hardware description language - HDL), buscando-se a economia de recursos de hardware. Os resultados numéricos discutem o tempo necessário para execução da técnica de correção de pacotes com erros, levando em consideração as restrições de tempo do padrão IEEE 1901.2. Além disso, uma análise de taxa de dados na camada PHY mostra que a implementação está de acordo com o padrão IEEE 1901.2 e pode perfeitamente satisfazer as necessidades de aplicações para SG e IoT. Ademais, a análise do uso de recursos de hardware e do consumo de energia mostram que o protótipo do transceptor NB hybrid PLC/Wireless demanda menos que uma vez e meia os recursos de hardware e o consumo de energia do protótipo do transceptor NB PLC. / This thesis focuses on a prototype of the so-called narrowband (NB) hybrid power line communication (PLC)/Wireless transceiver, which jointly uses power line and wireless channels, in parallel, for data communication related to smart grid (SG) and Internet of Things (IoT) applications. To build the prototype, it is introduced an enhanced and adapted version of the IEEE 1901.2 Standard to implement the medium access control (MAC) sublayer and the physical (PHY) layer to transmit data through both channels. The enhancement is based on the use of the Hilbert transform to recover the quadrature information from both channels, enabling to estimate the frequency deviation between the transmitter and receiver’s clocks. One adaptation in the IEEE 1901.2 Standard is the introduction of a routing protocol, which enables the transceivers to communication with nodes two hops or farther from each other. The other adaptation is the implementation of a packet error correction technique at the link layer level, which combines packets with errors received from PLC and wireless media and correct them, under certain constraint. Moreover, relevant is the fact that the NB hybrid PLC/Wireless transceiver is compatible with the NB PLC transceiver based on the IEEE 1901.2 Standard. The NB hybrid PLC/Wireless transceiver prototype is implemented in a field-programmable gate array (FPGA) device and details about the implementation, using a hardware description language (HDL), are provided, highlighting the pursuit of hardware resource savings. Numeric results discuss the time analysis of the packet error correction technique, calculating its maximum capacity of correction taking into account the IEEE 1901.2 Standard time constraints. Furthermore, a PHY layer data-rate analysis shows that the implementation agree with the IEEE 1901.2 Standard and can perfectly satisfy the needs of SG and IoT applications. In addition, the hardware resource usage and power consumption analysis show that the NB hybrid PLC/Wireless transceiver prototype demands less than one and a half times the hardware resource usage and power consumption of the NB PLC transceiver prototype.
103

The design of a software architectural framework for tunnelling metering protocols over TCP/IP and low bandwidth packet switched networks with support for proprietary addressing

Von Gordon, Albert Fredrich Johannes 25 October 2007 (has links)
This document discusses the concept of drivers implemented within the context of the REMPLI (Real-Time Energy Management over Power line and Internet, see section 1.8.) network. The process image approach and the tunnelling approach are presented and reasoning is given why the tunnelling approach is preferred. Each of the drivers implemented is associated with a specific metering protocol. This document further discusses the general architecture of such a driver structure. The generic software architecture serves as a framework for integrating serial communication based metering protocols over packet-orientated remote networks and meters, by tunnelling the protocol data units to the remote meters. Principally each Protocol Driver consists of three parts, one part situated at the Application Server, one at the Access Point and one at the Node. This document then gives a description of the general driver structure within the REMPLI network and briefly explains the functions of all the modules contained within the driver structure. An example is used to show how these modules, which make up the software architecture of the Protocol Driver, are used to send an application generated request from the Application Server to the Metering Equipment and sending the response back from the remote Metering Equipment to the Application Server. This dissertation further discusses the need for address translation within the REMPLI network and the need to restrict access to meters by using these addresses and an access control list. This document also discusses the need for a “Keep-alive” signalling scheme, if supported by the underlying protocol and gives a general concept as to how it should be implemented. The role of an Optimization Module is also discussed for low bandwidth networks by means of an M-Bus example. Finally the M-Bus protocol driver implementation is discussed. The results achieved are presented, showing that the driver architecture can successfully be used to tunnel the M-Bus protocol to remote meters, provided the underlying network conforms to the quality of service requirements determined by the implemented metering protocol. The work proposed in this document started off as part of the REMPLI project by the REMPLI team but was completed independently. / Dissertation (MEng (Computer Engineering))--University of Pretoria, 2008. / Electrical, Electronic and Computer Engineering / unrestricted
104

Návrh provozu sítě 110 kV napájené z transformovny 400/110kV Čebín / Design of the operation of 110 kV power network powered from 400/110 kV Čebín switching station

Kubizňák, Miroslav January 2008 (has links)
Knowlege of elektric power, power dissipation and voltage conditions in every single segments and elektric power system nodes is necessary for operations control and designing of another elektric power system expansion. In this Thesis, we will handle with steady state of system calculation using PAS-DAISY-OFF LINE software, solving various power network configurations and their verification.
105

Modely distribuční sítě / Distribution network models

Hrabčík, Oldřich January 2011 (has links)
This thesis deals with transmission of data over power-line. There is theoretically described PLC technology and its classification, properties and used modulation techniques. A substantial part is focused on the mathematical description of distribution network using two methods, with multipath propagation and ABCD matrix. These methods are mutually compared. Furthermore, they are examined depending on the transfer functions of the topology and capabilities for unknown topology. Calculations of transfer functions are implemented using Matlab. The results were then processed graphically and evaluated.
106

Parametry silnoproudých vedení / Power line parameters

Kavan, Pavel January 2011 (has links)
At the beginning is diploma thesis focused on a distribute power line parameters measurement and examination changes of this parameters depending on using of various power line cables. On the basis of measurements is made a transmission channel in Matlab & Simulink, where are executed simulations with power transmission line. The simulated power line is based on measured distribute parameters or physical proportions of cabels. By changing different parts of simulated communication channel is a symbol error rate expressed on the lenght of transmission line.
107

Ovládání domácích spotřebičů po silovém rozvodu / Powerline control of home appliances

Letocha, René January 2010 (has links)
The work deals with communication options, the power line and particularly the use of this technology in home automation to control heating and reduction in standby mode for selected domestic appliances. The issue is outlined in detail first and then examined in detail. The publication outlines a possible variant of such a device that can detect movement in the house and on the basis of such information to adjust the energy profile. The device is from its base designed to minimize the consumption of heat and electricity.
108

Model distribuční energetické sítě / Power distribution network model

Bradáč, Lubomír January 2012 (has links)
The thesis is focused on PLC technology issues and thus the data transmission over a power-line. This work describes characteristics of the PLC technology, its usage, functional principles and used modulation techniques. The main part of the work describes individual kinds of interferences in the network. The method of necessary steps against these interferences by using the right modulation and relevant coding is also described in the thesis. On the basis of theoretical knowledge, the models of interferences are realized in Matlab/Simulink. The simulative model of power-lines with random parameters is designed and realized for each elected techniques of modulation (BPSK, QPSK, ASK, FSK). The method of PLC channels modeling is chose as a multipath signal spreading for topology with one and two branching and the dependence of their transmission functions are inquired too. The analysis of interference influence on the data transmission is performed via the created models. All acquired results are compared and evaluated in the conclusion of this thesis.
109

Úzkopásmová PLC komunikace se standardy G3-PLC, PRIME a IEEE-1901.2 / Narrowband PLC communication based on G3-PLC, PRIME and IEEE-1901.2 standards

Skrášek, Tomáš January 2015 (has links)
Diploma thesis is about narrowband PLC communication standards. The theoretical part describes details of all available OFDM standards including G3-PLC, PRIME, IEEE-1901.2 and G.hnem. The practical part deals with PRIME and G3-PLC standards. In this part is also compared OFDM technology with system of single carrier frequency in environment with real interferences. The last part describes developement of two firmwares for PLC modems Texas Instruments TMDSPLCKIT-V3, which allow UART communication and remote data collection. The thesis also includes Windows application developed to display and save collected data.
110

Výpočet ustáleného chodu sítě 110 kV / Calculation of the network steady state on the voltage level 110 kV

Macháč, Petr January 2014 (has links)
This thesis deals with load flow calculation of electrical network 110 kV before and after the connection to the 70MW gas supply and the 58MW steam and gas supply. This grid can be powered from two 400/110kV substations, namely Sokolnice and Otrokovice. The load flow calculation is realized for the power supply either from Otrokovice or Sokolnice. Furthermore, the calculation of the uni-phase and three phase short circuits in the substations of 110kV network is realized in this thesis. The result of the thesis is the assessment of the voltage ratio in the network, current load of the power line and short circuit resistance of the substations.

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