Low Voltage Power Line Research Articles

Influence of Ambient Temperature on the Reliability of Overhead LV Power Lines with Bare Conductors

The article presents a study on the influence of weather factors (ambient temperature) on the operational reliability of overhead low-voltage power lines with bare conductors. A method for determining the average failure intensity, average failure duration, average renewal intensity, and failure rate of overhead low-voltage power lines with bare conductors as a function of ambient temperature is presented. Based on many years of observations of power lines operated in electric power distribution networks in Poland, the empirical values of the above-mentioned reliability indicators were determined. An analysis of empirical distribution compliance with the assumed theoretical model was also carried out. The reliability studies conducted showed that the highest failure intensity of the considered power lines occurred at temperatures commonly found in Poland.

Characterizing MIMO Channels in Low-Voltage Electric Power Line Communication through Impedance and Scattering Parameters Analysis

Characterizing MIMO Channels in Low-Voltage Electric Power Line Communication through Impedance and Scattering Parameters Analysis

ERRATUM: Characterizing MIMO Channels in Low-Voltage Electric Power Line Communication through Impedance and Scattering Parameters Analysis

ERRATUM: Characterizing MIMO Channels in Low-Voltage Electric Power Line Communication through Impedance and Scattering Parameters Analysis

Research on Efficient detection method of low voltage power line based on edge intelligence

Research on Efficient detection method of low voltage power line based on edge intelligence

Evaluation on the method of restoring the complex communication environment in the field based on the complex low pressure platform simulation platform

Abstract In recent years, with the development of smart grids, people have increasingly high requirements for the safety, stability, and reliability of smart grid operation. In actual operation, smart grids require real-time monitoring and control, while for low-voltage power lines, power line carrier communication is required for data transmission. However, in practical applications on site, the low-voltage power line environment is complex, with ground faults, electrical equipment interference, and other situations that can affect communication quality and reliability, leading to a decrease in the effectiveness of real-time monitoring and control. The research in this paper is based on a complex low voltage platform simulation platform to restore the on-site complex substation communication environment. The purpose is to improve the efficiency of automatic meter reading systems by using various communication methods in low-voltage substations, such as wireless public network point-to-point data transmission, optical fiber communication data transmission, power line carrier data transmission, etc. Automatic meter reading systems are an important means of low voltage substation communication. This article experimentally tested the maximum personnel allocation for meter reading using low voltage carrier communication technology, which was 8 people smaller than the maximum personnel allocation for traditional meter reading, and the minimum personnel allocation was 8 people smaller than the traditional meter reading personnel allocation. The electricity accuracy of meter reading using low voltage carrier communication was up to 96 %, while the electricity accuracy of traditional meter reading was 70 %. The maximum accuracy of line loss statistics for low voltage carrier communication technology meter reading was 90 %, while the maximum accuracy of line loss statistics for traditional meter reading was 68 %. The frequency of load anomalies found in low-voltage carrier communication meter readings within a month ranged from 30 to 60 times, while the traditional meter readings concentrated on 10–25 times. From these data, it is clear that communication meter reading in low-voltage station areas has advantages over traditional meter reading.

Research and analysis on noise characteristics of low voltage power lines carrier communication

Noise is one of the most important factors affecting the reliability of low-voltage power line carrier communication. In order to fully grasp the noise characteristics, a channel analysis equipment has been designed to collect and analyze noise. The analysis results show that power line noise is mostly manifested as a combination of colored background noise and pulse noise, mainly concentrated in the frequency band below 700kHz. Compared with the low peak period of electricity consumption, the peak period has stronger time-varying noise, larger amplitude of background noise, richer components of pulse noise, and there is also jitter in the duration of periodic pulse noise.

Low Voltage Power Line Physical Topology Recognition Method Based on Data Drive

The current traditional low-voltage power line physical topology identification method mainly detects the line pulse signal to identify the line topology, leading to poor identification effects due to the lack of correlation analysis of node voltage. A data-driven low-voltage power line physical topology identification method is proposed in this regard. The correlation between the node timing voltages is analyzed by exploring the voltage law to determine the connection between low-voltage power lines. The node resistance values are also calculated to convert the physical topology identification problem into a linear equation problem. In the experiments, the proposed method is verified for identification accuracy. The analysis of the experimental results shows that the proposed method has a low root-mean-square error and better recognition accuracy when recognizing the physical topology of low-voltage power lines.

Method of Calculation the Load Rates and the Unbalance Rates of the Current of the Phases in the MV/LV Network of the Sales and Service Center Lemba in Kinshasa

In this article, we discuss the calculation of load and current imbalance rates, which is a steady-state study of the distribution network that consists of determining, for each subscriber station, the operating rate of the installed power transformer and the current difference between two phases of the MV/LV distribution station. Knowing the allowable currents of each low-voltage phase of the subscriber substations from the busbars as well as the rated current of the substations transformer, we can calculate, secondly, the average currents and load factors of the substations including the differences between the currents and their unbalance factors in the low-voltage distribution power lines. The mathematical equations of the electrical quantities of the power system facilitate the evaluation of the performance of the power transformer. These equations confirm that the variation in load ratio and current imbalance of three phases are closely related to the current draw of the allowable loads at each phase.

Problems Related to Selected Methods and Techniques of as-Built Surveys of Low- and Medium-Voltage Electricity Connectors with a Practical Discussion

Abstract The aim of the paper was to analyse problems related to the inventory (as-built survey) of low and medium voltage power lines. Measurement methods and techniques were analysed as well as the influence of the network type (low and medium voltage) on the as-built survey procedure. For this purpose, information obtained from five as-built survey reports of medium and low voltage using different measurement methods was also used. Three of them were sample as-built survey of low voltage cable lines measured by tacheometric method, one as-built survey of medium and low voltage lines measured by GNSS method and one of low voltage cable made by indirect method using cable locator and measured by GNSS technology. The paper analyses the differences arising from the accuracy of the measurement, the difficulties encountered during the implementation, the time-consuming nature of the work performed, taking into account safety aspects for the persons performing the work.

Design and Research of Channel Circuit Based on Broadband Power Line Carrier

In order to effectively improve the anti-attenuation, anti-noise and anti-impedance change capabilities of the low-voltage narrowband power line carrier communication unit, reduce the carrier signal coupling attenuation, and highly fidelity signal power encoded and modulated by the carrier chip, an improved high-speed power line carrier communication transceiver circuit is designed. Using 303.13kHz~357.81kHz as sub-carrier signal frequency can effectively avoid the random noise generated by high-power power electronic equipment and household appliances below 35kHz. At the same time, to prevent the frequency crosstalk of power line carrier products with 270kHz and 421kHz as the center frequency, the Y-coupling capacitor and sixth order Butterworth band-pass filter circuit are used to design the signal receiving and transmitting circuit of the communication unit to isolate unwanted signals. The experimental simulation of the designed circuit is carried out on the circuit simulation software Multisim 12. The results show that the designed power line carrier communication transceiver circuit can effectively control the signal coupling attenuation within 4dB, and the filtering of unwanted signals can also reach 41.7dB, which has good application value.

Topology Identification of Low-Voltage Power Lines Based on IEC 61850 and the Clustering Method

The large-scale access of distributed power puts forward higher requirements for the monitoring of the distribution networks, and the topology identification of low-voltage power lines can effectively promote the integration of monitoring data and the distribution network information, effectively realizing the rapid identification of faults and ensuring the safety of users. In this paper, the method of graph theory was used to simplify the analysis of low-voltage lines, and the full topology identification strategy was proposed. Based on IEC 61850 SCL topology configuration information, line topology identification within the region was realized, and the correlation between regions was determined by the injection method. According to the configuration information, regional association information, and user’s collection information, the low-voltage station area line topology was divided into known regional topology and unknown regional topology. Aiming for the identification of line topology in the unknown region, according to the similarity of voltage fluctuations over short electrical distances, clustering analysis of user’s voltage data in the unknown region was carried out based on the k-means clustering algorithm. The test results showed that this scheme can realize the identification of topology in the region.

Gabor-YOLONet: A lightweight and efficient detection network for low-voltage power lines from unmanned aerial vehicle images

Maintaining and monitoring low-voltage overhead power lines are of great importance because such lines are the key link between the power system and low-voltage power users. At present, few networks can be detected accurately on intelligent edge identification devices because of the complex backgrounds and limited characteristics in unmanned aerial vehicle images as well as the low computing abilities of hardware. In order to give consideration to accuracy and speed, a novel power line detection method was proposed, denoted by Gabor-YOLONet, used for intelligent edge identification devices available to UAV. Unlike existing methods, the proposed method uses the Gabor algorithm to extract foreground of power lines from cluttered backgrounds automatically and predict power lines and their auxiliary targets such as insulators in the foreground scene. In addition, a new inference method was introduced, which can summarize the average location and orientation of auxiliary targets by clustering to verify the rationality of the predicted results for power lines. The experiment results showed that the proposed method had the higher accuracy and consumed less computing resources; compared with other methods, the mAP of identification for power lines was 86.6% and the running time was only 25 ms, with excellent performance on intelligent edge devices.

Performance Analysis of Power Line Communication System for Massive Indoor IoT Applications

This study explores the utilization of low-voltage indoor power line communication (PLC) technology within the framework of a split centralized radio access network (C-RAN) architecture, aimed at enhancing 5G indoor mobile coverage for the Internet of Things (IoT). A primary focus of this investigation is the comprehensive evaluation of the system’s performance in terms of radio and access latency. Several critical variables come into play, including available bandwidth, the chosen transmission technology, and the number of wireless IoT devices within the network. An analytical model, employing queuing theory, Markovian models, and stochastic geometry, is formulated to assess the radio-access delay spanning the air interface and the innovative PLC-based front-hauling system proposed in our previous study. The precision of this model is validated through simulations, ensuring that the proposed system effectively meets the stringent latency constraints required by eCPRI, thus contributing to the improvement of 5G indoor mobile coverage for the IoT network.

ПЕРЕДУМОВИ СТВОРЕННЯ МЕХАНІЗОВАНИХ ПІДЙОМНИКІВ ДЛЯ ОБСЛУГОВУВАННЯ ПОВІТРЯНИХ ЛІНІЙ ЕЛЕКТРОПЕРЕДАЧ

The article is an overview and the information presented is of an overview nature and is devoted to a very important topic in our time, namely the prerequisites for the creation of mechanized lifts for the maintenance of overhead power lines. The purpose of the work is to create prerequisites for the synthesis of new designs of individual mechanized lifts using the method of differential morphological analysis. The design of the lifts should ensure operation on low-voltage overhead power lines with supports of different cross-sections. The main design and operational requirements for lifts were defined, namely: the lifter must be universal for the power line supports used or be quickly reconfigured in the field and without the use of special tools; the hoist must have a reliable fixation in the working position on the power line support,LEP, which prevents involuntary sliding or falling of the lift, and also does not depend on the state of the power unit, power supply, etc.; the lift must use only the existing structural elements of the power line support for its movement;it is not allowed to equip the supports with addi-tional elements such as hanging cables, guides, etc.; the lift should not damage the structural elements of the supports used for its movement, that is, there should be no damage to the paint, anti-corrosion coating on metal supports, formation of dents and other damage on concrete and wooden supports, this is especially important in climatic conditions, in which Ukraine is located, since such damages become foci of corrosion and destruction of the support structure;the lift must have mass and dimensional characteristics that allow it to be transported in cargo or cargo-passenger vehicles of category "B" and above, as well as on trailers (semi-trailers) to them. We considered the classification of the supports of power lines themselves, the classification of lifts for maintenance of power lines. The classification of elevators in Ukraine was also considered, the shortcomings of existing elevators were determined, and based on the analysis of existing elevators, the closest analogue of the structure of the elevator planned to be developed was proposed.

The application of an integrated monitoring system for power distribution and consumption

In view of the fact that the traditional integrated power distribution and consumption monitoring system and power information acquisition system are independent of each other, and the data between the two systems are not shared and reused, which brings great obstacles to the construction of new power systems, this paper proposes an integrated power distribution and consumption monitoring system. The system can simultaneously collect distribution monitoring data and power consumption information data, and accurately perceive the panoramic data of power systems such as high voltage power line, distribution transformer area, low voltage power line, metering tank and so on. Through big data statistical analysis and accurate prediction of fault events, realize the two-way interaction between distribution side and power consumption side, reduce power maintenance costs, improve power supply quality, it provides a strong guarantee for the safe operation of power distribution and electrical equipment.

Four-Legs D-STATCOM for Current Balancing in Low-Voltage Distribution Grids

The fast deployment of distributed energy resources (DERs) is creating a series of challenges that should be addressed in the coming years. In particular, distribution grids are playing an increasingly important role in the electricity system. Moreover, the three-phase four-wire structure of this network contribute to the appearance of imbalances and a series of problems derived from them. In this context, distribution system operators (DSOs), as the main responsible for the distribution grid, must ensure the quality of supply to consumers. This paper takes advantage of a four-legs D-STATCOM to remove current imbalances in low-voltage power lines. A 35-kVA prototype has been developed and installed in an urban distribution grid. The effect of the D-STATCOM has been analyzed during its first month of operation, studying and measuring the advantages of providing DERs the ability to perform active balancing to the utility grid. The results show a reduction in current imbalances from 21 % to 0 % and neutral current from 10.3 A to 0.4 A. In addition, a 13 % decrease in cable losses has been estimated and a slight improvement in voltage unbalance factor can be noted.

Information Fusion Method of Power Internet of Things Based on Low-Voltage Power Line and Micro-Power Wireless Communication

In order to improve the coverage and reliability of the information perception layer of the power Internet of things, a method of constructing a cross layer fusion network of low-voltage power line and micro-power wireless communication (CPW) is proposed. Firstly, a unified medium access control (MAC) layer model of CPW is established to provide basic support for realizing the integration of CPW network layers; then an improved ant colony algorithm combining Brownian motion and local convergence times control is proposed to complete the networking process of CPW; Distribute the sub-service flow of CPW, and propose the bit error rate requirement factor in the service distribution, and accomplish the cross-layer integration of low-voltage power line and micro-power wireless communication network. The simulation results show that the communication link service quality of the cross-layer fusion network is better than that of the power line and wireless dual-mode or cascaded communication networks. The communication efficiency of CPW is improved to 398.20kbits/s. The coverage of the power line and wireless communication fusion network can be expanded by setting corresponding bit error rate demand factors according to different services. It takes into account the balance of communication link quality and network load.

Vibration-Based Status Identification of Power Transmission Poles

Among the power transmission infrastructures, the low-voltage overhead power lines are specifically critical, due to the complicated roadside environments and the significant number of connections to the end utility users. Maintaining of such a large size grid with mostly wood poles is a challenging task and knowing the operating status and its structural integrity drastically speeds up the routine inspection. Applying a data-driven approach using accelerometer data to analyze the power line-induced vibration to classify different poles within different operational conditions is proposed.Feature creation is the important aspect to improve an accuracy of data-driven algorithms. For this purpose, a time-frequency domain classifier is developed, based on the data collected from two tri-axial accelerometers installed on the wood poles before and after streetlights are on. Data are explored both in time and frequency domain using techniques such as data augmentation and segmentation, averaging, filtering, and principal component analysis. Results of the machine learning classifier clearly shows distinct characteristics among the data collected from different work conditions and different poles. Further exploration of the applied algorithm will be pursued to construct more sophisticated features based on supervised learning to enhance the identification accuracy.

Pulse interference identification and suppression for OFDM signal

The new generation smart meter is the core node of information acquisition and flows in the power Internet of Things (IoT). Because it is powered by the low-voltage power line, various short-time pulse interference signals in the line can be easily coupled to the received signal of the communication module embedded in the meter, resulting in the degradation of communication performance. In view of this situation, an identification-suppression algorithm of the short-time pulse-interference signal is proposed. The core idea is to comprehensively judge the existence of the interference signal and its specific position in the time domain based on the energy ratio of adjacent OFDM symbols and the change of mean square error value between frequency domain amplitude signals. Based on this, an interference energy elimination scheme with an adaptive threshold is realized. Theoretical analysis and simulation results show that the scheme has low computational complexity, high accuracy of pulse interference identification and position judgment, and can effectively reduce the energy of pulse interference signal, and thus improving the decoding performance of OFDM while it receives signals.

Noise Elimination of Low-Voltage Power Line Communication Channel using Time-Frequency Peak Filtering Algorithm

There are a lot of noises in the low-voltage power line communication (LVPLC) channel, which seriously damages the LVPLC system. The noise in the low voltage power line can be divided into general background noise and random pulse noise. These two noises will cause serious interference to the communication process based on LVPLC, reduce the signal-to-noise ratio of LVPLC system, and the communication quality cannot meet the requirements. To ensure the communication quality, this paper uses the time-frequency peak filtering algorithm to eliminate the noise in the LVPLC in the experimental environment. Firstly, this paper studies the noise characteristics based on the measured LVPLC channel noise. Secondly, the memory noise model is established, and the time-frequency peak filtering algorithm is used to eliminate the noise. In order to analyze the denoising effect of time-frequency peak filtering algorithm, the algorithm is simulated. Finally, the application effect of the algorithm is verified by experimental test. The simulation and application results show that the time-frequency peak filtering algorithm can improve the signal-to-noise ratio by about 5 dB in the actual noise environment of LVPLC, which can adapt to the changeable environment of LVPLC channel noise, and has good noise suppression effect and good application value. The application in the solar panel data transmission system shows that the time-frequency peak filtering algorithm can meet the communication performance requirements of the laboratory, reduce the bit error rate by about 2 % under the general background noise interference, and reduce the bit error rate by about 3 % under the pulse interference environment, and improve the transmission quality of LVPLC system.