Line Communication Technology Research Articles

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.

BPL-PLC Voice Communication System for the Oil and Mining Industry

Application of a high-efficiency voice communication systems based on broadband over power line-power line communication (BPL-PLC) technology in medium voltage networks, including hazardous areas (like the oil and mining industry), as a redundant mean of wired communication (apart from traditional fiber optics and electrical wires) can be beneficial. Due to the possibility of utilizing existing electrical infrastructure, it can significantly reduce deployment costs. Additionally, it can be applied under difficult conditions, thanks to battery-powered devices. During an emergency situation (e.g., after coal dust explosion), the medium voltage cables are resistant to mechanical damage, providing a potentially life-saving communication link between the supervisor, rescue team, paramedics, and the trapped personnel. The assessment of such a system requires a comprehensive and accurate examination, including a number of factors. Therefore, various models were tested, considering: different transmission paths and types of coupling (inductive and capacitive), as well as various lengths of transmitted data packets. Next, a subjective quality evaluation study was carried out, considering speech signals from a number of languages (English, German, and Polish). Based on the obtained results, including both simulations and measurements, appropriate practical conclusions were formulated. Results confirmed the applicability of BPL-PLC technology as an efficient voice communication system for the oil and mining industry.

Monitoring High Voltage Power Lines Using Efficient WSN

The power transmission line is one of most critical components in electrical power system. In order to enhance the reliability of the large power systems, an advanced and efficient Wireless Sensor Network (WSN) must be employed along power transmission line. However, time delay has emerged as one of the most critical issues in the design of WSN-based monitoring network of transmission lines. This paper proposes a new model for WSN for monitoring High Voltage Transmission Line (HVTL) which improves the needed time delay to transmit the measured quantity from transmission line towers to the control center. The proposed design considers the broadband power line communication (BPLC) technologies to transmit the collected data from group of towers to the nearest substation. To evaluate the performance of proposed model, the maximum time delay in data flow for the proposed model is determined in mathematical form and compared with other common models. The results of this paper demonstrate that the maximum time delay of proposed model less than the other common models, especially when advanced wireless communication, such as 4G and 5G, is used between the relay nodes. Based on the simulation results, the proposed WSN-based transmission line monitoring is efficient, powerful, reliable, and applicable to meet the smart grid requirements.

Decrepit Building Monitoring Solution for Zero Energy Building Management Using PLC and Android Application

Since power line communication (PLC) technology has been considered a platform technology for smart metering, this study introduces an analogous system technology for the PLC-based monitoring systems in zero energy building management. This technology allows a system operator or an operation center to monitor, calculate, or manage power use remotely through the existing power line so that individual suppliers will be able to grasp the present condition of power use and respond to any unexpected incidents. As in any country, many old buildings in Korea are repaired to be used for 40–50 years or even longer since constructing new ones is expensive. Because remodeling old buildings is not only expensive but also generates construction waste, repairing is the preferred alternative in many cases. With the expectation that the proposed platform technology will be one of the promising technologies for sustainable building, its uninterrupted power usage monitoring and remote power control/management functions will be quite useful for economizing power with convenience. A system with such a PLC-based design and algorithm can be quite scalable as well. As the major contribution of this study, a solution suitable for decrepit buildings or apartments has been developed by using the PLC technology, and the test bed experiment was conducted for it. The result showed that the solution worked flexibly and efficiently. Since it is impossible to install a new network especially in the case of decrepit buildings, PLC must be used through the existing power line. Thus, a decrepit building monitoring system has been proposed in this study for a sustainable building. The proposed solution was simulated with OPNET simulation first. Following the mounting of the actual PLC product and development of a monitoring application to complete the platform/solution, it is being tested at the test bed in a decrepit building.

The on-line communication in organization of rehabilitation of patients of traumatological orthopedic profile

Medical and sociological study used sampling of 381 patients involved in hip-and-knee joint replacement program before the surgery and in rehabilitation period with the use of specially designed and implemented at the base of the V. I. Razumovsky Research Institute of Traumatology, Orthopedics and Neurosurgery of Saratov State Medical University interactive system of monitoring and feedback (SMF). The implementation of developed criteria of SMF performance confirmed its demand among the patients. It was revealed that more than 91% of them are ready for active rehabilitation after surgery and all the participants of the study consider as acceptable the distant communication with medical specialists. The performed trial test established that for the period of interaction with SMF patients have changed their attitude to the ways of communication preferring those which suppose on line communication. The developed organizational technology being patient-focused provided acceptable quality of informational interaction for health services access at the base of active feedback, interactivity and customization. It is shown that aged but able-bodied patients are impressionable for such practice, so using of on line communication influencing labor and social activity prolongation being both factor and instrument of health services accessibility.

Characteristic Impedance Analysis of Medium-Voltage Underground Cables with Grounded Shields and Armors for Power Line Communication

The characteristic impedance of a power line is an important parameter in power line communication (PLC) technologies. This parameter is helpful for understanding power line impedance characteristics and achieving impedance matching. In this study, we focused on the characteristic impedance matrices (CIMs) of the medium-voltage (MV) cables. The calculation and characteristics of the CIMs were investigated with special consideration of the grounded shields and armors, which are often neglected in current research. The calculation results were validated through the experimental measurements. The results show that the MV underground cables with multiple grounding points have forward and backward CIMs, which are generally not equal unless the whole cable structure is longitudinally symmetrical. Then, the resonance phenomenon in the CIMs was analyzed. We found that the grounding of the shields and armors not only affected their own characteristic impedances but also those of the cores, and the resonance present in the CIMs should be of concern in the impedance matching of the PLC systems. Finally, the effects of the grounding resistances, cable lengths, grounding point numbers, and cable branch numbers on the CIMs of the MV underground cables were discussed through control experiments.

Statistical Learning for Service Quality Estimation in Broadband PLC AMI

In this paper, we propose a method to estimate communication performance for the advanced metering infrastructure that employs the power line communication (PLC) technology. Using bit-per-symbol signals from the PLC network management system, we estimate a PLC model quality in terms of packet success rate based on statistical learning. We also verify the accuracy of the estimations by comparing them with measured communication test results at test sites. Finally, from the packet success rate estimate, the qualities of services, such as meter readings and time-of-use pricing data downloading under several metering protocol sequences, are investigated through a mathematical analysis, and numerical results are provided.

Trasmission amplitude management in power line communications through a fuzzy logic controller: A real case study

The Power Line Communications (PLC) technology allows the use of the power grid in order to ensure the exchange of data among devices. This technology is particularly useful in those environments where wired technologies are preferable, mainly for reasons related to reliability of communications. However, although the PLC technology has been investigated by researchers in several fields, such as communication protocols and impact due to noise, this paper focuses on a little investigated issue: the power consumption of devices. It is shown an approach, based on fuzzy logic, that dynamically manages the amplitude of the signal, with which each node transmits, by processing the master-slave link quality measured and the master-slave distance. The main objective is to reduce the power consumption during transmissions by managing some very important network information related to noise (link quality) and the distance from which derives the channel attenuation. The controller has been implemented on Matlab/Simulink and subsequently integrated into the ADD1010 microcontroller, a power line System on Chip (SoC). The paper described two test-bed scenarios. The first has been realized in laboratory and the second is a real case study represented by a street lighting system in the city of Castellana Sicula, Italy. In both cases, the TH/WL ratio (number of packets received divided by the number of packets sent) and the power consumption of each device were measured. The obtained results show that network information, like noise and distance among devices, can be positively used in order to reduce the power consumption and the overall TH/WL of the network.

Fusing Power Line Communication (PLC)Technologies and Nigerian National Grid Network:Making Sense from Knowledge Management (KM)

This paper presents Power Line Communication (PLC) technology as an efficient means of knowledge sharing among corporate organizations in the power industry. The study considered power system organisational relationship in the conceptual view of knowledge management (KM). National grid system is underutilised in the view of organisational applications in communication system. A designed process could be initiated to address the gap of underutilisation of PLC technology. The integration of PLC technology in Nigeria could unified disjointed knowledge and promote professional efficacies in power system. The study heighted possible challenges and strength of incorporating Power Line Communication (PLC) into the existing power grid in Nigeria.

Battery Management through PLC-CAN Communication

This article presents a new method allowing data exchanges between a Battery Management System (BMS) and the application’s Energy Management System (EMS). The proposed solution is based on the Power Line Communication (PLC) technology and harnesses the versatility of the well-known Controller Area Network (CAN) protocol. This new PLC-CAN communication system is depicted in the context of the management of a distributed battery pack composed of several batteries connected in a star topology. Limits of the system are exposed, arising from the trade-off between the carrier frequency and the length of the power cables. A theoretical approach through simulation is proposed and shows the feasibility of the PLC-CAN system. Measurements realized on an experimental setup confirm the validity of this new physical medium for the CAN protocol.

Comparative Study on Application Performance of PLC of Electric Energy Data Acquisition System

The electric energy data acquisition system is an important part of smart grid construction, and as well it is the essentail platform and core support of intelligent electricity service system. As the “neural network” of electric energy data acquisition system, the communication technology plays a vital role for improving the system performance. In this paper, we performed a comparative test associated with the application performance of electric energy data acquire solution, whilst considing both narrowband power line communication (PLC) and broadband PLC technologies. While comparing the test resuls in both laboratory ideal environment and comprehensive interference environment, it provides an important data support to master the performance of different PLC technologies in electric energy data acquisition system.

Effect of the Power Cable on Data Transmission Over a Pulsewidth-Modulated Network

Power line communication (PLC) technology has proved itself in the last decade as an interesting solution for data transmission and communication in domestic application. Lately, this technology has been considered as a potential solution for monitoring and diagnosis of a motor-fed inverter setup. Information issued from sensors would be sent via power cables back to the controller despite the harsh environment and the switching of the inverter. This paper discusses the use of PLC technology over a pulsewidth modulation network by underlining the effect of the power cable length and the inverter switching on communication. A new approach based on the measurement of scattering parameters is used for this purpose, and the effect of the cable length is analyzed. It is shown that, for long distances, the PLC technology may not be effective, and hence, it is not possible to use power cables for communication.

Research on Broadband Channel Characteristics and Hardware Testbed for Power Line Communication System

With the decision to construct the smart grids around China, the power line communications (PLC) on the low-voltage (LV) distribution networks have become one of the potential technologies to commute the information between the end users and the power provider. Comprehensive and well-founded knowledge of the LV power line channel is the foundation to establish realistic modeling of the channel characteristics. The growing power line communication (PLC) technology is providing new potential for emerging applications such as G3 and Prime. In this paper, we have proposed a OFDM based channel sounding test bed to measure PLC channel within frequency band 100 kHz-2 MHz. A souding signal for the PLC channel is designed and a time-domain measurement method for the time-varying PLC propagation is presented. The experimental results of PLC channel characteristics under different scenarios are and analyzed.

BER Performance of QPSK-Transmitted Signal for Power Line Communication under Nakagami-like Background Noise

Power line communication (PLC) technology is used in various areas of a smart grid. The extensive use of PLC technology has proved its key role in smart grids throughout the world. Despite PLC's advantages, it suffers from a difficulty in modeling and analysis of its power line channel. Many researchers have experimented and proposed channel models for their own defined environments; as a result, a unified model for the power line has not been presented. To overcome this problem partially, we used a Nakagami-m distribution like background noise and analyzed the performance of the binary transmission system in our previous work. In this paper, we compare the analytical and simulated BER (bit error rate) performances of QPSK (quadrature phase shift keying) transmission system with Gray encoding. We verify that the analyzed and simulated performances are well matched for different values of m.

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.