Use Of Power Line Communication Research Articles

A novel fault monitoring method based on impedance estimation of power line communication equipment

Due to the close relationship between power grid fault and impedance, there is a significant defect in the use of power line communication (PLC) equipment to monitor and locate power grid faults, which is the lack of real-time impedance information. Therefore, this study proposes a new fault monitoring method based on impedance estimation of power line communication equipment. The channel frequency response (CFR) obtained from the PLC receiver is used to estimate the high-frequency input impedance to monitor and locate the ground fault of the power grid in real time. Firstly, based on the multi-conductor transmission line theory, bottom-up channel modeling method and impedance estimation technology, the basic principles of fault monitoring and location methods are clarified. Then, modeling and analysis of cables in different situations are carried out, and the characteristics of the factors affecting the impedance in CFR are extracted by variational modal decomposition (VMD), and the estimation results of impedance are obtained by inversion analysis. Based on this, the impedance change and machine learning algorithm are used to track and identify the abnormal state of the power line to achieve high-sensitivity positioning of the cable fault. The simulation results show that the method has a good identification effect on high and low impedance cable fault, and has a better effect on low resistance fault monitoring. The fault location error is less than 2.13%, and has a good positioning accuracy.

Communication Distance Estimation for Power Line Communication Using Various Differently Constituted Power Cables

The use of PLC (power line communication) is growing as the adoption of IoT technology becomes more widespread. However, the maximum communication distance between PLC modems cannot yet be clearly defined since the communication characteristics of the power lines used for PLC are not formally specified. In this paper, the propagation characteristics in the high‐speed PLC communication band of 2–30 MHz were investigated when equipment is not connected to the power line except both ends. The line constants for five typical types of cables used as single‐phase and two‐wire power lines were measured. Our results showed that different cables have markedly different transmission characteristics. The attenuation constant varied up to fourfold depending on the cable insulator material. We also derived a method of estimating the communication distance for different cables for application of the HD‐PLC system, which is the most commonly used type of high‐speed PLC. The measurement result by using VCT cable was almost agreed with the estimated value. By comparing the estimated distance with the experimental results, we show that the transmission distance can be estimated with sufficient accuracy for practical use. © 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.

Web-Based Toolkit for Performance Simulation and Analysis of Power Line Communication Networks

AMIs (Advanced Metering Infrastructures) present an important role in Smart City environments, especially from the point of view of distribution and customers, offering control and monitoring capabilities. The use of PLC (Power Line Communication) technology offers a wide range of advantages in AMI, including not needing to deploy an additional communication infrastructure. However, the electrical network was not initially designed for communications, as these networks pose problems depending on the connected loads, such as network impedance variation, frequency selectivity or noise. For this reason, the use of simulators is proposed to facilitate the deployments based on PLC networks, and analysis and diagnosis tools for the identification of problems in operating networks are also required. This paper presents a toolkit for evaluating and analyzing the performance of PLC networks. This toolkit is composed of SimPRIME, a simulator for the evaluation of NB-PLC PRIME (PoweR line Intelligent Metering Evolution) networks’ performance; SimBPL, a simulator for the evaluation of MV-BPL (Broadband Power Line over Medium Voltage) cells’ performance; and PRIME Analytics, a forensics tool that allows diagnosis of communication problems in PRIME operational networks based on traffic traces. The toolkit has been developed throughout several research projects in close collaboration with DSOs (Distribution System Operators) and equipment manufacturers, so they provide solutions to actual problems of these industry key players and have been adapted to facilitate their use. As a result, the tools are accessible through web applications to increase their usability, portability, and scalability. These applications represent the first steps in offering PLC simulation and analysis as a service that could benefit the research community, academia, and industry.

Signal Attenuation of Data Transmission by Power Lines

Power Line Communication (PLC) technologies are actively developing and becoming more and more in demand all over the world. They are used in the automation of technological processes, the organization of video surveillance systems and even to control a "smart" home. Research in the field of data transmission using the power grid has been going on for a long time. Once upon a time, the use of PLCs was hampered by low data transfer rates and insufficient immunity from interference. The development of microelectronics and the creation of modern, and most importantly, more efficient processors (chipsets) made it possible to use complex modulation methods for signal processing, which made it possible to significantly advance in the implementation of PLC. However, only a few specialists still know about the real possibilities of communication technology over the power grid. The reliability of data transmission is greatly influenced by interference from various electrical appliances, fluorescent lamps, etc., which interfere with the wires. The strongest influence of impulse noise arising from the operation of electric motors, welding equipment and microwave ovens. However, reliable methods of encoding and encrypting data used in modern PLC technologies provide not only a high level of reliability in the transmission of information, but also its protection from unauthorized access. In addition, when organizing communication, electromagnetic compatibility must be ensured, i.e. it is necessary to reduce the spurious electromagnetic radiation arising from the process of data transmission. Today PLC finds wide practical application. Due to the fact that the technology uses the existing power grid, it can be used in the automation of technological processes for linking automation units via electric wires (for example, city electricity meters). The widespread use of low-voltage electrical networks 0.22 ... 0.38 kV, the absence of the need to carry out expensive work on the construction of trenches and punching walls for laying cables stimulate an increased interest in these networks as a data transmission medium. Often, PLCs are used to create video surveillance systems or a local area network in small offices, where the main requirements for the network are ease of implementation, device mobility and easy scalability. At the same time, both the entire office network and its individual segments can be built using PLC adapters. It is often necessary to connect a remote computer or network printer located in another room or even at the other end of the building to an existing office network - using PLC adapters, this problem can be solved in a few minutes. In addition, PLC technology opens up new opportunities for implementing the idea of a "smart" home, in which all consumer electronics must be tied into a single information network with the possibility of centralized control. The article discusses the basic principles of using power lines as a communication channel, and ways to build such networks. Also, it offers to get acquainted with the main problems of this technology and ways to solve them.

The Use of Power Line Communication in Standalone Microgrids

Standalone microgrids are used in various industrial operations to supply critical loads. The authors have proposed a stable and robust decentralized ac microgrid architecture that provides an automatic and equitable load sharing between distributed generators, without the use of droop control. To deal with faults or real-time changes in the distributed generation levels, a flexible reconfiguration of the microgrid can be advantageous. To achieve that, this article proposes the use of power line communication (PLC). Two PLC strategies are explored in this article: the first is based on using a single and constant PLC frequency, and the second is based on using a variable PLC frequency within a given range. This article details PLC injection, detection, and suppression methods, as well as the overall communication logic. It demonstrates the ability of the microgrid to adapt to changes while minimizing the amount of battery support. Findings of this article are supported by simulations and validated by experiments.

Hybrid Visible Light and Power Line Communication for Indoor Multiuser Downlink

Visible light communication (VLC) turns indoor light-emitting diode (LED)-based illumination devices into high-speed network portals that, for example, operate in tandem with existing Wi-Fi networks. Since in this scenario, multiple VLC-equipped luminaires would serve overlapping service areas, we suggest the use of power line communication (PLC) to coordinate and provide data to the VLC transmitters. In particular, in this paper, we propose a hybrid VLC-PLC (HVP) system architecture for the indoor downlink transmission and present the analytical framework for the data rate analysis of the HVP system. In our solution, spatial optical OFDM (SO-OFDM) is applied across multiple luminaires, for which we propose several subcarrier allocation schemes to exploit the frequency selectivity of the VLC and PLC channels. Different possible and meaningful variations of the HVP system, including the choice of optical OFDM transmission, relay, and multiple access schemes, are investigated and compared. The numerical results establish achievable rates for relevant communication scenarios and highlight the advantages of the proposed subcarrier allocation scheme in terms of rate and reduced peak power of optical OFDM signals.

The Channel Characteristic and AMR Field Trial Results in China Distribution Grid

Power line communication (PLC) has received much attention recently because of the need of reliable and automatic metering, In this paper we present a comprehensive study over the use of PLC in China. We begin with some background including the distribution grid topology, the power line channel environments, and the deployment of PLC network. Then we show some field test results of PLC-based meter-reading in a high frequency band. In addition, a suggestion how to improve G3-PLC is presented which can adapt China grid better.

Development of a PLC modem for data transmission over a PWM power supply

In variable-speed electrical drive and online conditioning monitoring, a feedback loop is required in order to transmit the sensor information from the motor to the controller close to the inverter. Additional cabling is used for signalling. This extra cabling has a significant cost and data transmission may not be reliable. Thus, the use of power line communication (PLC) technology to transmit data in motor drive application is quite interesting. The use of a PLC modem dedicated to the home network in a three-phase inverter-fed motor power cable does not work. Therefore, specific coupling interfaces are developed to transmit data through a pulse-width modulated power supply. Laboratory tests have shown that the couplers are operating properly. They ensure reliable data transmission in a motor drive application.

Power line enhanced cooperative wireless communications

In this paper, we investigate the use of power line communication (PLC) to assist cooperative wireless relaying. We consider a communication scheme that uses the power line to initialize and synchronize wireless amplify-and-forward relays and to broadcast information between the relays. Starting from an analysis of transfer functions and noise measurements of PLC channels in office and residential environments, we propose a power line transmission scheme for the inter-relay-communication and assess the influence of this scheme on wireless relaying. This scheme is based on linear precoded orthogonal frequency-division multiplexing; it is designed to optimally exploit the frequency diversity available on PLC channels. The use of PLC leads to a very flexible way of enhancing wireless communications by plugging in additional relays where they are needed-without additional wiring.