1,463 research outputs found
Communications for smart grid substation monitoring using WIMAX protocol
The SMARTGRID is a general term for a series of infrastructural changes applied to the
electric transmission and distribution systems. By using the latest communication and
computing technology, additional options such as Condition Monitoring can now be
implemented to further improve and optimise complex electricity supply grid operation.
Lifecycle optimisation of high voltage assets and other system components in the utility
provide a case in point. Today Utility experts agree that application of scheduled
maintenance is not the effective use of resources. To reduce maintenance expenses and
unnecessary outages and repairs of equipment due to scheduled maintenance, utilities are
adopting condition based approaches. Real time online monitoring of substation
parameters can be achieved by retrofitting the existing substation with SMARTGRID
technology. The IEC 61850 is a common protocol meant for Substation Automation
Systems, designed for the purpose of establishing interoperability, one that all
manufacturers of all different assets must comply with. This thesis advocates the estimation
of bandwidth required for monitoring a substation after retrofitting the existing substation
with smart communication technologies. This includes establishing a latest wireless
communication infrastructure from the substation to the control centre and evaluating the
performance modelling and simulating the physical layer of communication technologies
such as WIMAX (IEEE802.16) and MICROWAVE point to point using MATLAB
SIMULINK and RADIO mobile online simulation software. Also, link budget of the
satellite communication for the same application is calculated. Satellite communication in
this case is considered as a redundant or back up technology to ensure that the
communication between entities is continuous. On performing the simulation on different
environments the results prove that the selected protocols are best suited for condition
monitoring. The measured Latency could be the best approximated value which complies
with the current objective. However the white noise that exists in the substation has
significant hazard with respect to the security of the wireless network. To compensate this
constraint whole substation is hard wired by means of plastic fibre optics and the data sent
to the base station located near the substation
FTTx Access Networks: Technical Developments and Standardization
This chapter provides a review of factors driving technical development of broadband access networks, mostly toward higher bit rates and symmetrical services, together with a review of “fiber to the x” (FTTx) technologies for fixed access networks, including development and performance limitations of digital subscriber line (DSL) systems using twisted-pair copper cables, as well as fiber to the home systems. Characteristics and standardization of these systems are presented, together with a review of the two main competing broadband technologies: Data over cable service interface specification (DOCSIS) in coaxial cable TV networks and the 4G and 5G wireless networks. Additionally, a short list of recent developments in passive technologies (fibers, cables, and connectors) is included. Finally, the issues related to dismantling of the traditional copper telephone network and ensuring continuity of voice services in emergency situations are analyzed
A Survey on Communication Networks for Electric System Automation
Published in Computer Networks 50 (2006) 877–897, an Elsevier journal. The definitive version of this publication is available from Science Direct. Digital Object Identifier:10.1016/j.comnet.2006.01.005In today’s competitive electric utility marketplace, reliable and real-time information become the key factor for reliable delivery of power to the end-users, profitability of the electric utility and customer satisfaction. The operational and commercial demands of electric utilities require a high-performance data communication network that supports both existing functionalities and future operational requirements. In this respect, since such a communication network constitutes the core of the electric system automation applications, the design of a cost-effective and reliable network architecture is crucial.
In this paper, the opportunities and challenges of a hybrid network architecture are discussed for electric system automation.
More specifically, Internet based Virtual Private Networks, power line communications, satellite communications and wireless communications (wireless sensor networks, WiMAX and wireless mesh networks) are described in detail. The motivation of this paper is to provide a better understanding of the hybrid network architecture that can provide heterogeneous electric system automation application requirements. In this regard, our aim is to present a structured framework for electric utilities who plan to utilize new communication technologies for automation and hence, to make the decision making process more effective and direct.This work was supported by NEETRAC under
Project #04-157
Non-Terrestrial Networks in the 6G Era: Challenges and Opportunities
Many organizations recognize non-terrestrial networks (NTNs) as a key
component to provide cost-effective and high-capacity connectivity in future
6th generation (6G) wireless networks. Despite this premise, there are still
many questions to be answered for proper network design, including those
associated to latency and coverage constraints. In this paper, after reviewing
research activities on NTNs, we present the characteristics and enabling
technologies of NTNs in the 6G landscape and shed light on the challenges in
the field that are still open for future research. As a case study, we evaluate
the performance of an NTN scenario in which satellites use millimeter wave
(mmWave) frequencies to provide access connectivity to on-the-ground mobile
terminals as a function of different networking configurations.Comment: 8 pages, 4 figures, 2 tables, submitted for publication to the IEE
Smart PIN: performance and cost-oriented context-aware personal information network
The next generation of networks will involve interconnection of heterogeneous individual
networks such as WPAN, WLAN, WMAN and Cellular network, adopting the IP as common infrastructural protocol and providing virtually always-connected network. Furthermore,
there are many devices which enable easy acquisition and storage of information as pictures, movies, emails, etc. Therefore, the information overload and divergent content’s
characteristics make it difficult for users to handle their data in manual way. Consequently, there is a need for personalised automatic services which would enable data exchange across heterogeneous network and devices. To support these personalised services, user centric approaches
for data delivery across the heterogeneous network are also required.
In this context, this thesis proposes Smart PIN - a novel performance and cost-oriented context-aware Personal Information Network. Smart PIN's architecture is detailed including its network, service and management components. Within the service component, two novel schemes for efficient delivery of context and content data are proposed:
Multimedia Data Replication Scheme (MDRS) and Quality-oriented Algorithm for Multiple-source Multimedia Delivery (QAMMD).
MDRS supports efficient data accessibility among distributed devices using data replication which is based on a utility function and a minimum data set. QAMMD employs a buffer underflow avoidance scheme for streaming, which achieves high multimedia quality without content adaptation to network conditions. Simulation models for MDRS and
QAMMD were built which are based on various heterogeneous network scenarios. Additionally a multiple-source streaming based on QAMMS was implemented as a prototype and tested in an emulated network environment. Comparative tests show that MDRS and QAMMD perform significantly better than other approaches
EXTRACTION OF PICTORIAL ENERGY INFORMATION FROM CAMPUS UNMETERED BUILDINGS USING IMAGE PROCESSING TECHNIQUES
In recent years, advanced metering infrastructure (AMI) has been the main research focus due to the traditional power grid has been restricted to meet development requirements. There has been an ongoing effort to increase the number of AMI devices that provide real-time data readings to improve system observability. Deployed AMI across distribution secondary networks provides load and consumption information for individual households which can improve grid management. Significant upgrade costs associated with retrofitting existing meters with network-capable sensing can be made more economical by using image processing methods to extract usage information from images of the existing meters. This thesis presents a new solution that uses online data exchange of power consumption information to a cloud server without modifying the existing electromechanical analog meters. In this framework, application of a systematic approach to extract energy data from images replaces the manual reading process. One case study illustrates the digital imaging approach is compared to the averages determined by visual readings over a one-month period
System for acquisition, processing and presentation of energy consumption
Tese de mestrado integrado. Engenharia Electrotécnica e de Computadores (Major Telecomunicações). Faculdade de Engenharia. Universidade do Porto. 200
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