194 research outputs found
Influence of LED tubes on the throughput of an indoor broadband PLC channel
Abstract: This paper shows how Light Emitting Diode (LED) Tubes negatively influence the data rate throughput of an indoor broadband Power Line Communications (PLC) channel. This negative influence on the data rate is due to noise being generated by the lamps. Differential Mode measurements were done with two PLC modems communicating and then introducing LED lamps that add noise to the channel. Drops in data throughput rates were measured and compared to a clean (no noise) channel. A significant decrease (up to 50%) in throughput was observed which can have important implications for applications of PLC in the presence of LED Tubes
Impact of modern lighting technology on the power line communications channel
Abstract: In this study, we look at the impact of modern lighting technology on Power Line Communications (PLC). Power Line Communications has become important due to the Smart Grid and Internet of Things (IoT) development. Modern lighting technology has been developed to make efficient use of electric energy. This technology uses power converters to enable the use of different lighting sources. A byproduct of this conversion process is electronic noise. This noise can interfere with the PLC channel. In this study, different lighting technologies are investigated from a noise standpoint and compared to PLC signal levels. Both narrowband and broadband PLC frequency ranges are investigated. This study shows that the influence of noise on the PLC channel depends predominantly on the conversion topology as well as whether filters have been used. The measurement results show that the influence on data communication system can vary in impact from low to severe. Results were obtained for low energy, high energy, indoor and outdoor lighting sources. A common front end topology encounted is the bridge rectifier and high frequency DC-DC converter combination. These topologies are investigated in details. The study presented here shows that lighting technology (causing interference) needs special consideration when designing PLC systems. Of particular importance is the use of filters which ensure compliance with interference standards and limit the noise effects on the PLC signal.D.Ing. (Electrical and Electronic Engineering Science
Širokopojasni prijenos podataka elektroenergetskom mrežom
The paper presents an overview to broadband over powe lines. Over the past few years advances in signal processing technology have enabled the advent of modem chips that are able to overcome the transmission difficulties associated with sending communications signals over electrical power lines. There are two predominant types of BPL communications configurations: Access BPL and In-Home BPL. One of the largest commercial markets for BPL is the ability to provide Internet Services by means of the Transmission Control Protocol/Internet Protocol (TCP/IP) protocols. Another significant benefit of BPL is the ability to employ “intelligent” power line networks that make use of SCADA devices.U radu je opisan pregled širokopojasnog prijenosa podataka elektroenergetskom mrežom. Razvoj tehnologije prijenosa signala omogućio je prevladavanje problema prijenosa komunikacijskih signala putem elektroenergetske mreže. Time je omogućen širokopojasni prijenos podataka kojim se osigurava pristup Internetu koristeći postojeću infrastrukturu. Ovakva komunikacija dijeli se na: pristupnu i kućnu. Najveći ekonomski značaj ove tehnologije je mogućnost pružanja pristupa Internetu TCP/IP protokolom. Osim pristupa Internetu omogućava i implementaciju pametne elektroenergetske mreže (SCADA)
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Performance Evaluation of Powerline Technology on Low Voltage Distribution Networks
Powerline technology (PLT) employs the electrical distribution network to transmit data in addition to supplying power. PLT is currently employed to provide data networking in many domestic environments, and is expected to play a major part in the development of the forthcoming Smart Grid.
Given that the electrical distribution network was not designed with data transmission in mind, electromagnetic radiation from the network can give rise to interference. Regulators and researchers have considered the impact of such widespread radiation, and investigations of the various aspects of powerline have been conducted over the last decade. Despite this prolonged period, however, there remains a lack of agreement on the typical performance of such networks or the implications for regulation policy.
An accurate model of the radio frequency (RF) properties of the typical electrical distribution network would be extremely valuable in developing standards and informing policy. The aim of this thesis is to provide a cohesive approach to determining the RF characteristics of a typical domestic property and applying such parameters to model the performance of PLT.
The thesis reviews the recent development of broadband PLT, the progress made by the more prominent regulators, and the trials undertaken to define the key parameters affecting propagation. A detailed experimental programme carried out both in the laboratory and at typical sites is described.
An empirical model of the RF performance of a UK domestic low voltage distribution network (LVDN) is developed from analysis of the experimental results. It is shown via this analysis that discrete measurements of the conducted and radiated parameters can be related and that the RF performance of the LVDN can be described by Conversion and Radiated Loss. The radiated field is shown to comprise the combined common mode current to the LVDN and common bonding network (CBN).
The thesis concludes with consideration of the future development of powerline technology, particularly in support of the Smart Grid development
Powerline Kommunikation: Wesentliche Technologien um PLC in CE-Geräte zu integrieren
In-house PLT (Powerline Telecommunication) enables new and highly convenient networking
functions without the need for additional cables on mains-powered devices. Since wireless
networks are not able to reach sufficient throughput between different rooms or even floors,
PLC is considered to be the ideal backbone home network medium, providing complementary
and seamless interaction with wireless networks.
The need to communicate information is not new. The historical overview of this thesis
compares the development of PLT to radio broadcast technologies. The consumer expects
technologies to operate without interferences. Today, there are coexistence problems between
these two technologies. Why does this happens, and how the problems can be resolved are the
main issues of this thesis.
Initial calculations of the channel capacity provide encouraging results for using the mains
cabling as a communication medium. Chapter 3 forecasts how PLT modems could develop in
the future. The usage of frequencies above 30 MHz will increase the throughput rate. Next, the
utilization of the 3rd wire (the protective earth) for communication enhances the coverage and
the reliability of powerline transmissions. The reception of common mode signals and the usage
of MIMO technologies enable 8 transmission paths between one pair of outlets, which
improves the performance of the bad, strongly attenuated channels.
Today, the main challenge for the mass deployment of PLT is the lack of harmonized international
standards on interoperability and electromagnetic interference. The absence of a standard
results in the undesirable situation of PLT modems interfering with technologies from
different vendors and also with radio applications. Solutions for solving these problems are
given in chapter 4 and chapter 5.
The approach of ‘Smart Notching’ - monitoring the existence of receivable radio broadcast
stations at the time and location where a PLT modem is operating, received wide resonance in
the PLT and radio broadcast communities. ‘Smart Notching’, also called ‘Dynamic Notching’
or ‘Adaptive Notching’ is considered to be the key factor in solving the endless discussions
about the interferences to HF radio broadcast. Details on the creation of ETSI TS 102 578 and
the implementation of a demonstrator system is documented in chapter 5. Field tests conducted
together with the EBU verified the efficiency of the concept. The jointly executed tests by representatives
from the radio broadcast and the PLT communities became a historical event
which brought the two technologies, radio receivers and PLT modems, back into one house.
Finally, a vision of the future coordination of EMC and conclusions are presented.Heutige Modems zur Powerline Telekommunikation (PLT) können im Betrieb den Empfang
von Kurzwellen-Rundfunk beeinträchtigen, wenn Modem und Rundfunk-Empfänger in
unmittelbarer Nachbarschaft betrieben werden. Eine neue Generation von PLT Modems, in
denen das Konzept von 'Smart Notching' - dem intelligenten Einfügen von Lücken in das
Kommunikationsspektrum - implementiert ist, zeigt keine Interferenzen mit dem Empfang von
Rundfunkdiensten.
Das Rauschen auf der Niederspannungsinstallation enthält neben sonstigen Signalen - durch
andere Geräte hervorgerufen - aufgrund der Antennenwirkung Information über Rundfunksender.
Beim ‚Smart Notching’ erkennen PLT Modems am Betriebsort die Existenz von Rundfunksignalen,
indem sie das Signalspektrum auf der Netzleitung messen. Die Echtzeit-
Bewertung der aktuellen Situation am Betriebsort ermöglicht eine Adaption des PLT Systems.
Damit wird die Elektromagnetische Verträglichkeit nicht a priori (zum Herstellungs-Zeitpunkt)
durch Schirmung oder eine globale Reduktion des Sendepegels, sondern durch Design des
Verfahrens (welches während des Betriebs angewendet wird) hergestellt.
Diese Doktorarbeit beschreibt nach einem kurzen Überblick zur Historie des Rundfunks
und der Datenübertragung über das Energieverteilnetz Messungen zur Ermittlung der theoretischen
Kanalkapazität. Anschließend wird ein Ausblick gegeben, wohin sich zukünftige PLT
Modems entwickeln werden. Dies sind vor allem der Frequenzbereich oberhalb von 30 MHz
sowie die Nutzung der dritten Kupferader in den Netzleitungen: der Schutzerde. Die Verwendung
von MIMO-Algorithmen (aus der kabellosen Funkübertragung (z.B. WiFi) bereits bekannt)
verbessert vor allem die Wahrscheinlichkeit, eine hohe Datenrate im Gebäude sicher zu
verteilen.
Sorge bereitet bei PLT ebenfalls die Koexistenz mit weiteren PLT-Systemen, sowie zu
xDSL. Hierfür wird ein Vorschlag gemacht, um die Interferenzen zu nicht kompatiblen PLToder
DSL-Systemen zu vermeiden, ohne dass die Systeme sich gegenseitig gezielt Informationen
zusenden.
Das bereits oben erwähnte Konzept des ‚Smart Notching’ wird detailliert erläutert und die
Implementierung eines Demonstrators auf FPGA-Basis dokumentiert. Abschließend wird noch
beschrieben, wie ‚Smart Notching’ gemeinsam mit der EBU getestet wurde und wie es seinen
Weg in die Welt der Standardisierung gefunden hat. Der Veröffentlichung des Standards ETSI
TS 102 578 wurde im Juli 2008 einstimmig von ETSI PLT zugestimmt
A modern teaching environment for process automation
Emergence of the new technological trends such as Open Platform Communications Unified Architecture (OPC UA), Industrial Ethernet, cloud computing and the 5th wireless network (5G) enabled the implementation of Cyber-physical System (CPS) with flexible, configurable, scalable and interoperable business models. This provides new opportunities for the process automation systems. On the other hand, the constant urge of industries for cost and material efficient processes demands a new automation paradigm with the latest tools and technologies which should be taken into account while teaching future automation engineers.
In this thesis, the modern teaching environment for process automation is designed, implemented and described. This work explains the connections, configurations and the test of three mini plants including the Multiple Heat Exchanger, the Three-tank system and the Mixing Tank. In addition, OPC UA communication between the server and its clients has been tested. The plants are a part of the state of the art of the architecture that provides the access of ABB 800xA to the cloud services via OPC UA over the 5G test wireless network. This new paradigm changes the old automation hierarchy and enables the cross layered communication in the old architecture.
This modern teaching environment prepares the students for the future automation challenges with the latest tools and merges data analytics, cloud computing and wireless network studies with process automation. It also provides the unique chance of testing the future trends together in this unique process automation setup
Energy Efficiency
This book is one of the most comprehensive and up-to-date books written on Energy Efficiency. The readers will learn about different technologies for energy efficiency policies and programs to reduce the amount of energy. The book provides some studies and specific sets of policies and programs that are implemented in order to maximize the potential for energy efficiency improvement. It contains unique insights from scientists with academic and industrial expertise in the field of energy efficiency collected in this multi-disciplinary forum
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