Three-phase Transmission Line Research Articles

Phasor Measurement Unit-Driven Estimation of Transmission Line Parameters Using Variable Noise Model

Accurate parameters are crucial in modern energy systems to ensure the reliable operation of all components. Given the substantial volume of data in monitored systems, high-performance methods are necessary. This paper proposes a new Bayesian multi-output regressor for estimating the parameters of a three-phase transmission line. The presented approach achieves acceptable accuracy in parameter estimation using only one end of the line. The Bayesian regressor is developed using information derived from the data themselves, eliminating the need to explicitly model the system. This capability allows the method to estimate parameters while accommodating different noise models, even in the presence of systematic errors and non-Gaussian random noise. The methodology was validated on various systems, including a two-bus system, IEEE 14-bus, IEEE 39-bus, and IEEE 118-bus, under diverse conditions such as varying sample sizes, loads, and noise levels. These tests demonstrate the robustness of the proposed approach.

A grid fault diagnosis framework based on adaptive integrated decomposition and cross-modal attention fusion

In large-scale power systems, accurately detecting and diagnosing the type of faults when they occur in the grid is a challenging problem. The classification performance of most existing grid fault diagnosis methods depends on the richness and reliability of the data, in addition, it is difficult to obtain sufficient feature information from unimodal circuit signals. To address these issues, we propose a deep residual convolutional neural network (DRCNN)-based framework for grid fault diagnosis. First, we design a comprehensive information entropy value (CIEV) evaluation metric that combines fuzzy entropy (FuzEn) and mutual approximation entropy (MutEn) to integrate multiple decomposition subsequences. Then, DRCNN and heterogeneous graph transformer (HGT) are constructed for extracting multimodal features and considering modal variability. In addition, to obtain the implicit information of multimodal features and control the degree of their performance, we propose to incorporate the cross-modal attention fusion (CMAF) mechanism in the synthesis framework. We validate the proposed method on the three-phase transmission line dataset and VSB power line dataset with accuracies of 99.4 % and 99.0 %, respectively. The proposed method also achieves superior performance compared to classical and state-of-the-art methods.

Using the Exact Equivalent π-Circuit Model for Representing Three-Phase Transmission Lines Directly in the Time Domain

This paper presents a novel three-phase transmission line model for electromagnetic transient simulations that are executed directly within the time domain. This model relies on distributed and frequency-dependent parameters, as well as employs modal transformation for its implementation. The single-phase model of the exact equivalent π-circuit is utilized for each propagation mode. This model combines discrete components, such as resistors, inductors, and capacitors, to accurately emulate the transmission line behavior via linear circuit elements. This model can be seamlessly integrated into various electrical circuit simulation software, thus allowing easy utilization and incorporating time-varying elements to analyze transmission lines. The JMarti model, which comes by default in the Alternative Transient Program, and the numerical Laplace transform method implemented in MATLAB were utilized to validate the proposed solution across various scenarios. An advantage of this model is its independence from the prior calculation of travel time and its exemption from convolutions, inverse Laplace transforms, and Fourier transforms, thus streamlining the simulation process.

Convolutional Neural Network for Transmission Line Fault Diagnosis Based on Signal Segmentation Approach

Convolutional Neural Network (CNN) is a Deep Learning algorithm that can take in an input signal, assign importance (learnable weights and biases) to various aspects of the signals and distinguish between them. The CNN algorithm trains a sample and obtains a CNN model capable of identifying different fault types to analyse transmission line faults. Fault analysis methods typically require feature extraction to synthesise the relevant and non-redundant information from the raw signals. However, these traditional methods are time-consuming and inconsistent, and they can produce biased results due to the reliance on human expertise and experience. Hence, this research focused on developing an intelligent system for fault detection in a three-phase transmission line using CNN. This research aims to develop a CNN model for automatic fault detection in a three-phase transmission line and evaluate the performance of the CNN model for analysing transmission line faults. The three-phase transmission line model was developed using MATLAB-Simulink. CNN was implemented to detect transmission line faults. The performance of CNN based on the signal segmentation approach was evaluated through three different types of data: ideal and noise-added signal data. The simulation result shows good performance accuracy of 99.11% for the ideal case, 99.36%, and 99.39% for 20 dB and 30 dB noise-added cases, respectively. The result shows that a higher noise value in transmission line fault current could increase the performance of CNN. In conclusion, the utilisation of CNN based on a signal segmentation approach for transmission line fault analysis has showed promising performance.

Alternative method to include the frequency-effect on transmission line parameters via state-space representation

This article describes an alternative method and investigates its performance on the transient responses considering a frequency-dependent lumped parameter model (FDLPM) to represent the transmission line (TL) in the literature. This model includes the fundamental behavior of the frequency dependency on longitudinal parameters, and it is developed directly in the time domain (without the use of frequency-to-time conversion tools). The alternative method individually solves a system of state-space equations for each π circuit of the LPM. Consequently, this method reduces the order of the state-space matrices, providing excellent performance associated with lower computational efforts (faster speed) compared to that obtained with the classical method. The alternative method was used to calculate the electromagnetic transients (current and voltages) in the single- and three-phase transmission lines subjected to energization maneuver and lightning strike for several scenarios at the receiving end. All responses are calculated using a programming code in MATLAB®. Results demonstrated that the alternative method closely follows the responses calculated with the classical, indicating its excellent accuracy. Besides, the smaller dimension of state-space matrices lead to low computational times, varying from 230 to 300 times smaller, depending on the line configuration compared to the other method, assuming the same fixed time step.

Examination of Gas Active Arc Extinguishing and Lightning Protection for Transmission Lines

The study investigated the gas active arc extinguishing and lightning protection for transmission lines. Lightning is one of the most significant sources of over voltages in overhead transmission lines. The lightning over voltages could lead to failure of the devices connected to the transmission line. Fundamental constraint on the reliability of an electrical power transmission system is the effectiveness of its protective system. The role of the protective system is to safeguard transmission system components from the effects of electrical overstress. Shield wire and surge arresters are an important means of lightning protection in transmission and distribution systems. Therefore, it is necessary to analyze the influence of over voltages caused due to lighting. The requirements of system security for lightning protection technology reach the high standard that lightning strike tripping and wire breakage are not allowed. Both the power supply side and the demand side have very high requirements for lightning protection of transmission lines, but the lightning accident rate remains high. This situation poses a great threat to the reliability and safety of power network, it is urgent to solve this problem. The gas active interrupter principle is put forward. From two latitudes of lightning overvoltage and power frequency over current, the effective control of lightning accident rate caused by large probability and multiple lightning strike is realized. This paper is aimed at evaluation of protection level of transmission line by using gas active arc extinguishing, shield wire and line surge arresters against lightning overvoltage. When lightning strikes, the internal short gap of the main body and the air gap break down, and the lightning arc enters the arc-extinguishing body through the breakdown channel. Arc is compressed by force to form internal and external gradients temperature in order to produce jet airflow. Jet airflow acts on the subsequent power frequency follow current arc, a model coupling an arc and a compressed jet airflow in a multi-fracture compression airflow arc-extinguishing structure is established and simulated. The increase in voltage due to lightning are investigated by using the MATLAB software. Direct and induced, types of lightning strokes are considered. The model of a 33kV three-phase overhead power transmission line is developed considering the RL circuit. The simulations are performed based on time domain analysis. Also, numerical analysis is made for 133kV tower structure transmitting power over 220km from 132 KV Sub-transmission Lines in port Harcourt region. Based on the simulation study this research study gas active arc extinguishing and lightning protection for transmission lines, are very important in computer application like Electromagnetic Transient Propagation (EMTP) and Power System Computer Aided Design (PSCAD) which are used in future study. These soft wares provide an alternative way to bring the precise result in study of lightning protection level of high voltage transmission line.

Transmission Line Voltage Measurement Utilizing a Calibrated Suspension Grounding Voltage Sensor.

The accurate voltage measurement of distribution networks is of great significance in power dispatching and fault diagnosis. Voltage sensors based on the spatial electric field effect do not require grounding, which provides the possibility for the distributed measurement of transmission line voltages. However, the divider ratio of suspension grounding voltage sensors is affected by the height between the sensor and the ground, as well as the distance between the sensor and the telegraph pole. In this paper, a self-calibration method based on internal capacitance transformation is proposed to realize the on-line calibration of suspension grounding voltage sensors. The calibration is accomplished by switching different parameters in the conditioning circuit, and the calibration process does not require power failure or known input excitation. In addition, the impact of electric fields in the other two phases of three-phase transmission lines on measurement through simulation research is quantified in this paper. In order to reduce the impact of interference electric fields, an equipotential shielding structure is designed. The circuit topology and probe prototype have been developed and testing has been conducted in laboratory conditions; the experimental results show that the maximum relative error of voltage amplitude is 1.65%, and the phase relative error is 0.94%. The measurement accuracy is not limited by the height to ground or the distance to the telegraph pole. In addition, in the application of an equipotential shielding probe, the maximum deviation of measured voltage is 0.7% with and without interference electric fields.

Research on simulation and detection of space electric field distribution of deteriorated insulators in three-phase over-head transmission lines

Operation accidents caused by deteriorated insulators occur from time to time, which poses a direct threat to the safe and stable operation of transmission lines. Much research has been done at home and abroad on the degradation mechanism of deteriorated insulators, the electric field distribution characteristics of insulator strings and the influence of deteriorated insulators on the space electric field, but there is little research on the influence of three-phase electrification on the space electric field of insulator strings. Therefore, this paper studies the simulation and detection of electric field distribution of deteriorated insulators in three-phase transmission lines. First, the difference between three-phase electrification and single-phase electrification on the space electric field of insulator strings is simulated and analyzed, and the influence of deteriorated insulators on the space electric field distribution of insulator strings under three-phase electrification is studied. Second, based on simulation results, a detection method for deteriorated insulators in three-phase overhead trans-mission lines is proposed, and a non-contact space electric field measurement device based on Unmanned Aerial Vehicle (UAV) is developed. Finally, a Unmanned Aerial Vehicle inspection system is used to test the transmission lines in combination with an electric power department, and the simulation results and the effectiveness of the proposed detection method are verified. Results show the electric field distribution of insulator strings is obviously different between three-phase electrification and single-phase electrification, and when the detection distance is 300 mm, the proposed detection method and device can effectively identify deteriorated insulators in three-phase transmission lines.

Shunt faults detection and classification in electrical power transmission line systems based on artificial neural networks

PurposeThis study aims to focus on an adaptive method for fault detection and classification of fault types that trigger in three-phase transmission lines using artificial neural networks (ANNs). The proposed scheme can detect and classify several types of faults, including line-to-ground, line-to-line, double-line-to-ground, triple-line and triple-line-to-ground faults.Design/methodology/approachThe fundamental components of three-phase current and voltage were used as inputs in the ANNs. An analysis of the impact of variations in the fault resistance, fault type and fault inception time was conducted to evaluate the ANNs performance. The survey compares the performance of the multi-layer perceptron neural network (MLPNN) and Elman recurrent neural network trained with the backpropagation learning technique to improve each of the three phases of the fault detection and classification process. A detailed analysis validates the choice of the ANNs architecture based on the variation in the number of hidden neurons in each step.FindingsThe mean square error, root mean square error, mean absolute error and linear regression are measured to improve the efficiency of the ANN models for both fault detection and classification. The results indicate that the MLPNN can detect and classify faults with a satisfactory performance.Originality/valueThe smart adaptive scheme is fast and accurate for fault detection and classification in a single circuit transmission line when faced with different conditions and can be useful for transmission line protection schemes.

Strategies of Energy-Efficient Active Filtering in the Two Wattmeter Reference Frame

Such basic concepts of power theory as apparent power, active current and minimum power losses in the transmission line are defined for a three-phase three-wire system in the shortened two wattmeter reference frame. On the basis of these concepts, two energy-efficient active filtration strategies were developed and verified by virtual experiments. The first of them minimizes the power losses of a three-phase three-wire transmission line with different values of its resistances and ensures a unit value of the power factor. The second strategy follows the recommendation of IEEE Std. 1459-2010 ensures the minimum power loss of the transmission line with symmetrical sinusoidal currents of a three-phase source.

Innovative method to identify the impedance parameters of a three-phase electric power medium-size transmission line

Innovative method to identify the impedance parameters of a three-phase electric power medium-size transmission line

The use of artificial neural network for low latency of fault detection and localisation in transmission line

One of the most critical concerns in power system reliability is the timely and accurate detection of transmission line faults. Therefore, accurate detection and localisation of these faults are necessary to avert system collapse. This paper focuses on using Artificial Neural Networks in faults detection and localisation to attain accuracy, precision and speed of execution. A 330 kV, 500 km three-phase transmission line was modelled to extract faulty current and voltage data from the line. The Artificial Neural Network technique was used to train this data, and an accuracy of 100% was attained for fault detection and about 99.5% for fault localisation at different distances with 0.0017 μs of detection and an average error of 0%–0.5%. This model performs better than Support Vector Machine and Principal Component Analysis with a higher fault detection time. This proposed model serves as the basis for transmission line fault protection and management system.

Two Terminal Instantaneous Power-Based Fault Classification and Location Techniques for Transmission Lines

Transmission lines are an important part of the power system, as they are the carriers of power from one end to another. In the event of a fault, the power transferring process is disturbed and can even damage the equipment, which is attached to the generation end as well as the user end. Most of the power systems are connected to the transmission lines, so it is very important to make the transmission lines secure. For protection purposes, relays are used, but relays only trip in the event of a fault and do not tell us about the location of the fault. The power system requires a speedy protection system. For a speedy protection system, quick and fast fault analysis and classification are required. An effective approach for the analysis of the transmission line with three sources is proposed. This method is quite effective and accurate for locating the fault and classifying its types. This technique needs power measurement from both ends simultaneously for fault diagnosis. Instantaneous power and sign power values are used for fault detection and classification. A voltage profile is used to identify the fault location. For three-phase transmission lines, voltage profiles are built up at different segment points to locate the fault. The IEEE-9 bus system is simulated for this technique. MATLAB is employed for simulation purposes. The test system is simulated with different types of faults at different locations. Relay operation has not affected the accuracy of the system. This technique has an accuracy of more than 97%. This method is quite effective for the analysis of power transmission lines. It can discriminate the fault type, identify the faulty phase of the line, and locate the point of the fault. Faults are located with errors not more than 0.45%. Moreover, the time difference between the actual fault and the calculated fault obtained from the estimated location is not more than 0.004 s. Simulations are claimed to be executed in less computational time, ensuring effective and rapid protection against faults.

Identification Method for Pulse Wave Resulted From Fault Transient of Overhead Transmission Line

This paper presents a simple and effective method to extract the identification quantity of transient pulse waveform produced by the overhead transmission line short-circuit fault. This method employs the second-order time harmonic equation of the power frequency component to convert the fault full-wave data. After the conversion, only the identification quantity remains. This method can amplify high-frequency spectral content by the times of the square of the angular frequency, and hence improve the sensitivity of identifying fault transient. Using the identification quantity, one can clearly observe the arrival time and relative intensity of fault transient. A three-phase half wavelength transmission line of 50Hz/3000km is simulated with PSCAD to illuminate the effectiveness of this method. The effects of fault type, soil resistivity, fault resistance, power frequency fluctuation, sampling rate, transposition length,fault inception angle and white noise are analyzed. Calculated results show that this method can distinguish different fault type and can work effectively at low sampling rate down to 10kHz. This method is helpful for improving the performance of the traveling-wave based fault location method.

РЕЗОНАНСНЫЕ ЯВЛЕНИЯ В ТРЕХФАЗНЫХ ЛИНИЯХ ЭЛЕКТРОПЕРЕДАЧИ, ПИТАЮЩИХ НЕТЯГОВЫХ ПОТРЕБИТЕЛЕЙ ЖЕЛЕЗНОДОРОЖНОГО ТРАНСПОРТА

The article is devoted to the analysis of the quality of electrical energy in three-phase power supply systems for 10 kV non-traction consumers receiving power from traction substations, taking into account resonance phenomena. Emphasis is placed on high-order harmonics, which negatively affect the operation of modern electrical equipment. The prediction of voltage and current resonances in three-phase power transmission lines feeding the non-traction consumers was carried out on the basis of calculations in MathCAD. SimInTech simulations were performed to study electromagnetic processes, including estimation of the higher voltage harmonics values taking into account resonance phenomena in consumers.

Implementation of an Alternative Frequency-Dependent Three-Phase Transmission Line Model Based on the Folded Line Equivalent Model in MatLab-Simulink

This paper proposes an alternative multiconductor transmission line model that combines the folded line equivalent with the modal transformation. The folded line equivalent decomposes the nodal admittance matrix of a transmission line into its open-circuit and short-circuit contributions. These contributions are fitted to rational functions, which are associated with Norton equivalent circuits based on their state space models. The proposed model uses an orthogonal matrix to transform voltages and currents from the phase domain to the folded line equivalent domain and vice versa. Because the transformation matrix is orthogonal, we represent it using ideal transformers in simulation software. First, we use a circuit representation of Clarke’s matrix to decompose a transmission line into its modes. Then, each mode is decomposed into its open-circuit and short-circuit contributions using a circuit implementation of the proposed matrix. The proposed approach can accurately represent short lines in simulations with time steps equal to or greater than the propagation time of the transmission line. We compare the results obtained with the proposed approach to those obtained with power systems computer-aided design/electromagnetic transients including the DC universal line model.

가공지선 불평형전류를 이용한 부하동작 전원용 변류기 제작 및 특성평가에 관한 연구

In this paper, the design, manufacture, and characteristic evaluation of the current transformer as a power source were discussed to use unbalanced currents flowing through the overhead ground line due to load imbalance in the three-phase four-wire transmission line. In the theoretical calculations on the output characteristics of a current transformer, approx. 30A of the unbalanced current show to produce enough power about 14.7W. And it is confirmed that the battery can be stably charged at 29.7W for the load operation even if the imbalanced current is about 20A. Therefore, it was shown that the current transformer and power supplies developed in this study can be sufficiently used as operating power sources for various loads installed in the transmission line.

Research on UAV Safety Distance Warning Technology Based on Electric Field Ring Rate of Change

With the increasing scale of transmission lines, drone inspection has become a major method of transmission line inspection. In the process of UAV inspection, the safety distance warning of UAV and transmission lines is crucial, and the existing UAV safety distance warning methods have difficulties, such as high cost, low environmental adaptability, and data processing. In this paper, we propose a safety distance warning method based on the rate of change of electric field ring ratio, which can be applied to the inspection process of transmission lines of different voltage levels. In order to accurately measure the electric field strength around the transmission lines, a three-dimensional electric field measurement system for measuring the electric field in space is designed in this paper. Finally, a 10 kV three-phase transmission line experimental platform was built to verify the feasibility of the method proposed in this paper.

A modified implementation of the Folded Line Equivalent transmission line model in the Alternative Transient Program

This paper proposes a modified implementation of the Folded Line Equivalent transmission line model to represent three-phase transmission lines. The Folded line equivalent decomposes a line into its open circuit and short circuit contributions. We propose an alternative orthogonal matrix to transform single-phase transmission line parameters, voltages, and currents to the Folded Line Equivalent domain. Because the proposed matrix is orthogonal, it can directly represent bidirectional transformations using circuit components in simulation software, such as the ATP-EMTP. First, the circuit implementation of Clarke’s matrix decouples a three-phase transmission line into its modes. Then, the circuit implementation of the proposed matrix decouples each mode into its open circuit and short circuit contributions. This paper proves that the proposed approach outputs similar results as those obtained by the Universal Line Model and the JMarti model in the simulation of transmission lines under open-circuit, energization, and fault conditions. However, because the proposed model does not derive from the method of characteristics, it can run with simulation times greater than the propagation delay of the transmission line. It is shown that the proposed approach outputs accurate results for time steps that are 10%, 100%, 200%, and 400% of the propagation delay of the transmission line. Thus, one major advantage of the proposed approach is that it can be used to reduce runtimes in the representation of short transmission lines in large complex networks by increasing time steps without compromising accuracy.

Fault Detection in Three-Phase Transmission Line by Using IoT

Abstract: The electrical energy device is cut up into many special sections. One in all is the transmission mechanism, wherein Power is transmitted from producing stations and substations through transmission strains to customers. Both strategies Should numerous kinds of malfunctions are generally stated as a "Fault" Fault is described as a number of unwanted however Unavoidable incidents can temporarily disturb the strong circumstance of the power system that occurs while the insulation of the System fails at any factor. Furthermore, if a carrying out object comes in contact with a bare power conductor, a quick circuit, or Fault. The causes of faults are, lighting stroke, human error, wind damage, timber falling or wines plants throughout transmission Strains, aircraft crash on the transmission line, birds shorting traces, or vandalism. At some point in this study, the causes and consequences of faults Within the overhead transmission strains have been the maximum target of the research. A variety of the numerous reasons for faults and some Detection strategies are going to be mentioned. Those faults cause goodsized damage to the power system equipment. In India It's ordinary, the faults might be LG (Line to ground), LL (Line to Line), or 3L (3 lines) inside the availability structures and those faults in 3 phase delivery can affect the strength plant. Keywords: Three-phase Fault, Node MCU, Transmission line, Line to Lind fault, Line to Ground Fault, IoT based.