Fault Location In Distribution Networks Research Articles

A Hybrid scheme for fault location in unbalanced multi-lateral distribution network with distributed generation

Fault location in an unbalancend multi-lateral distribution network having several branches, laterals, load taps and distributed generation is a major challenge. In case of multi-lateral distribution network, the fault location scheme needs to accurately locate the faulted line segment to avoid the problem of multiple fault location candidates. Traditional fault location schemes in such network employs additional measures to filter out the exact fault location out of the multiple candidates. To overcome the above mentioned problem, a new hybrid method combining high-frequency transient method and impedance based method is proposed in this work for fault location in a unbalacened multi-lateral distribution network. This method first identifies the line section with fault after that the impedance based method is utilized to locate the exact fault location. The simulation results obtained demonstrate that the proposed scheme for fault location is capable of locating all shunt fault type with good accuracy.

Reducing multiple estimation for fault location in medium voltage distribution networks

Short circuits are a matter of major concern in the protection of power distribution systems. They can lead to interruptions in energy supply, and consequently affect the quality of power delivered to consumers. In these situations, there is a need to determine a fault location to ensure that a technical crew can reestablish the system as fast as possible. However, in radial distribution networks, fault location is not a trivial task, as the presence of lateral branches will result in multiple estimations. In this context, the present article addresses the problem of multiple estimation, considering the response of an impedance-based fault locator. To validate the proposed analytical approach, the IEEE 34-node test feeder was used. Moreover, the approach was analyzed in terms of: (a) the percentage reduction of the multiple estimation regions (R%); (b) the number of meters allocated in the feeder; and (c) the distance errors estimated by the fault locator. The results demonstrate that the proposed formulation allowed a minor influence of errors deriving from the impedance-based fault locator and a good trade-off between the number of meters (investment) and the R%.

Current Sag and Mismatch Based Earth Fault Location for Distribution Network with Renewable Energy Resources

Fault diagnosis is increasingly becoming more challenging in distribution network due to complicated network topology and coupling disturbances introduced into the systems. This requires a higher level of rapidity and accuracy of fault diagnosis, location and recovery. This paper proposes an earth fault location algorithm for distribution network using current analysis. The fault information can be obtained by those measuring equipment that have already installed in critical nodes and generations. Then, the mechanism model is proposed to illustrate the equilibrium relationship of current flow in distribution network with renewable energy sources. The criterions named current sag and current mismatch are also proposed in this paper for fast fault area location and accurate fault node location. Assessment of this method is carried out using a distribution network model with renewable energy sources in PSCAD. The experimental results confirm the effectiveness and superiority of the proposed method in distribution network fault diagnosis over conventional methods.

Improved Fault Location Algorithm for Radial Distribution Network Based on Power Failure Information

As the scale of the distribution network continues to increase, the importance of distribution network is getting higher and higher. Therefore, it is necessary to achieve fault location and restore it as soon as possible after the fault occurs. This paper proposes a new fault location algorithm for the radial distribution network, which is improved on the basis of traditional matrix algorithm. First, the power failure incidence matrix (PFIM) and power interruption information matrix (PIIM) is constructed based on the topological connection and fault information at each node. The fault location matrix (FLM) is then obtained through PFLM and PIIM to realize the fault location. Second, the accuracy of the proposed algorithm is verified by mathematical derivation. Finally, an 11-node radial distribution network is illustrated to testify the proposed algorithm. Results show that the improved fault location matrix algorithm proposed in this paper can effectively achieve fault location in radial distribution network.

Online tracking of fault location in distribution systems based on PMUs data and iterative support detection

Fast and accurate locating of electrical faults along power networks enhances system reliability and continuity of supply, quick reclamation of the power supply and subsequently decreasing service outage time. This paper introduces a new technique for online tracking of fault location in distribution networks based on system measurements available from Phasor Measurement Units (PMUs) and Iterative Support Detection (ISD) technique. During and prefault, the voltages are measured by PMUs which are optimally located along the network. From the voltage change vector and system impedance matrix, a current change vector involving a nonzero element corresponds to the faulty point is obtained. Since PMUs are not placed at all buses, the acquired system equation is underdetermined. Therefore, ISD technique is used to solve and recover the current vector that is sparse in nature. The proposed method is verified by applying it to an 11-bus system, with and without the presence of Distributed Generation (DG). The method is then implemented on a 104-bus real distribution network in Egypt. Different case studies are presented considering the effect of fault resistance and measurement noises. A comparative study is proceeded to illustrate the performance of the proposed method. Results clarify that this method performs effectively for different network topologies and circumstances.

Block-Sparse Bayesian Learning Method for Fault Location in Active Distribution Networks With Limited Synchronized Measurements

Timely and accurate fault location techniques can reduce power outages and improve power supply reliability. This paper proposes a new fault location method for active distribution networks (ADNs) which utilizes limited synchronized measurements (μPMUs). The proposed method formulates the fault location problem as the estimation of a block-sparse fault injection current signal which can inherently reveal fault types and locations. A modified block-sparse Bayesian learning (BSBL) algorithm is utilized to estimate this block-sparse signal by exploiting its both block structure and intra-block correlation. In addition, the proposed method provides a strategy for the optimal placement of much fewer μPMUs that will not yield a complete observable system. The proposed method is able to pinpoint the fault position accurately, and is applicable to both balanced and unbalanced ADNs. The effectiveness of the proposed method is examined on the IEEE 123-node distribution network with DGs and the results are discussed thoroughly.

Technology and application of high speed fault location,isolation and self-healing in DC distribution network

With the continuous increase of DC load, the research of DC distribution network has been developed rapidly. Compared with the traditional AC distribution network, DC distribution network has the advantages of less conversion times, high efficiency, low cost, simple control structure, no need to consider the frequency and phase and reactive power compensation equipment. Compared with AC distribution network, DC distribution network has more flexible operation mode and less power supply points However, the more flexible operation mode of DC distribution network also brings the problem of fault location and self-healing. The fault location, isolation and self-healing control strategy of AC distribution network can not be applied to DC distribution network. In this paper, a high-speed fault location, isolation and self-healing method for DC distribution network is proposed. Based on high-speed goose communication, a comprehensive evaluation is carried out according to the fault status of the power grid, and the millisecond level fault location, isolation and self-healing of DC distribution network are completed. The coordinated control equipment based on this method is successfully applied in Tongli integrated energy service center. When the fault occurs in this area, uninterrupted power supply is realized in the non fault area, which verifies the correctness and practicability of this method.

Research on Fault Location Method of Distribution Network

Distribution network is an important part of the power system, is the core link of power distribution, and is also the key node in the process of power grid operation. Once the distribution network fails, it is very important to determine the fault location quickly and accurately for the restoration of normal power supply. Aiming at the problem of distribution network fault location, this paper introduces the research status of distribution network fault location method in detail, introduces the existing distribution network fault location method in detail, expounds its application situation, analyzes the advantages and disadvantages of various methods in detail, so as to provide reference for the future research of distribution network fault location method.

A Fully Decentralized Multi-Agent Fault Location and Isolation for Distribution Networks With DGs

The modern distribution automation suggests to enable decentralized self-healing of distribution networks using advance metering and controlling infrastructure. Decentralized fault location and isolation, as an essential and vital component of self-healing, has attracted considerable attention over the years. In this paper, an integrated fault location and isolation strategy based on fully decentralized multi-agents system (FDMAS) is presented for distribution system with distributed generators (DGs) by combining the primary protection with device failure protection (i.e., backup protection). The proposed FDMAS strategy can locate and isolate electrical fault rapidly even under device failures with minimum fault clearance time and range by using expert logical rules, meanwhile can detect and identify device failure adaptively. Furthermore, a unified programming framework is developed for generalization and application of the proposed strategy. The simulation studies are carried out on 22-bus distribution system by using dynamic model test platform. The test results show that the proposed strategy has an excellent performance on fault clearance time, fault isolation range and device failure detection.

Multi-Timescale-Based Fault Section Location in Distribution Networks

To meet the requirements of quickness and accuracy for fault location in smart distribution networks with high penetration of distributed generations, we propose an integrated fault section location method based on multiple timescales. On the millisecond timescale, we present a distributed fault section location method based on fault current polarity value comparison (PVC) using the first half-cycle fault current signal after the fault inception. On the cycle timescale, we implement a distributed fault section location method based on fault current waveform similarity comparison (WSC) using the first one-cycle fault current signal after the fault inception. On the second timescale, we adopt a fault section location method based on a genetic algorithm (GA) using the steady-state fault current signal. Three timescale fault section location methods thus coordinate with each other through constructed reliability functions of the fault section location methods based on PVC and WSC. The simulation results show that the multi-timescale-based fault section location method achieves a fast and accurate fault section location.

Novel Fault Location for High Permeability Active Distribution Networks Based on Improved VMD and S-transform

Aiming at the problem of the inaccurate fault location in high-permeability active distribution network, a novel method of fault location for active distribution network based on improved variational mode decomposition (IVMD) and S-transform is proposed in this paper. Firstly, the judgment method of instantaneous frequency is adopted to determine the value of decomposition layers k . Meanwhile the algorithm of variational mode decomposition (VMD) is utilized to decompose the fault signal of traveling wave. Then, the kurtosis criterion is employed to select the appropriate intrisic mode functions (IMFS) for S-transform in order to obtain the S-matrix with higher resolution. The high-frequency components in the matrix are extracted to determine the arrival time for the head of the fault traveling wave. Finally, the fault distance can be calculated by the special distance formula without considering the velocity of the traveling wave. The simulations show that the proposed method can accurately measure the fault distance for the transmission lines in high permeability active distribution network, and the measurement error is limited within 200m, which verifies the accuracy and effectiveness of the proposed algorithm.

Fault Location in Distribution Networks with the Presence of Distributed Generation Units Based on the Impedance Matrix

The study of “fault rapid detection and resolution” in the power network is particularly important in sensitive areas of the network. Today, the use of distributed generation in the distribution network is increasing. In the event of an accident, if the fault location is quickly identified, the recovery of the faulty network is accelerated and the shutdown time is minimized. Since distributed generation networks do not have the traditional methods of fault location, accurate and efficient performance, so in this paper, for the least interrupted power supply, a new method for locating and identifying the faulted part of the distribution system with the presence of distributed generation is studied. The proposed method is based on the impedance matrix of the distribution network which has high speed and accuracy in fault location and also has high accuracy in simulations considering the asymmetry of loads and network. In this paper, simulations are implemented in OpenDSS software under various fault conditions and the results are processed in MATLAB software.

Research on Fault Location in Distribution Network Based on Fast Fault Transfer Arc Extinguishing Device

In the distribution network equipped with fast fault transfer arc extinguishing device, after a single-phase grounding fault occurs, the fault phase bus is quickly grounded to realize arc extinguishing. At the same time, the traveling wave signal generated during the grounding process of the fault phase bus can realize fault location. The traveling wave signal is subjected to phase-mode transformation, and the time difference of the zero-mode component mutation detected twice at the exit of the fault line is to be recorded. This time difference is the time which it takes for the zero-mode component to go to and fro once between the bus and the fault point. And then the fault distance can be calculated based on it. The integration of arc extinguishing and fault location is realized. The AT P simulation software is used to realize the fault simulation of distribution network. And the accuracy and feasibility of the proposed fault location method are verified.

Fault Location in Active Distribution Networks Containing Distributed Energy Resources (DERs)

This paper presents a simple yet effective method for locating faults in radial distribution networks where impedance-based methods are known to have limitations, especially in the presence of inverter-based power sources (IBPS). The proposed approach utilizes the Discrete Wavelet Transform (DWT) to capture the first arrival times of the fault-generated traveling waves. It is assumed that a digital fault recorder (DFR) exists at the terminal node of every lateral, as well as the beginning and end of the main feeder. The detailed derivation of the fault location method is presented, and illustrative fault scenarios are simulated to experimentally verify the proposed algorithm's performance under very diverse conditions. It is shown that the proposed approach performs successfully irrespective of the unknown fault impedance, inception angle, and type.

Method for fault location in a low-resistance grounded distribution network based on multi-source information fusion

Several uncertain factors, such as the protection and circuit breaker refusing operation and misoperation, make it difficult to obtain accurate results based on a single fault location using the switching quantity. So this study proposes a power grid fault location method via multi-data source information fusion. The compressed sensing algorithm is used to reconstruct the electrical signal twice, and the rough fault range and electrical quantity fault degree are obtained respectively. Subsequently, the Bayesian network is used to obtain the switching fault degree of each element in the rough fault range. Finally, DS evidence theory fuses these two fault degrees to obtain the location result. PSCAD software builds an IEEE 14 node system, and the effectiveness of the proposed method is verified by simulation. Furthermore, it can quickly and accurately locate the fault after its occurrence and has good application prospects with respect to the fault location of a low-resistance grounded distribution network.

Analysis of Distributed Power Access on Distribution Network Fault Location and Voltage Quality

Distributed Generation (DG) has a certain impact on distribution network fault location and voltage quality during the access process, which is worth studying. In this paper, the impact of distributed power on the two is discussed separately, and further technical analysis is carried out with an example.

Research on IACA of distribution network fault location

In power system, the probability of distribution network failure is the highest, which will directly affect the power consumption experience of customers. The timely and accurate fault location of distribution network is very important to improve the reliability of power supply. In this paper, firstly, the switch function and evaluation function of distribution network fault location are discussed. ACA(Ant Colony Algorithm) algorithm has some defects such as premature convergence. In order to solve this problem, the IACA(Improvement Ant Colony Algorithm) method is proposed. Finally, the feasibility and effectiveness of the new method are verified by establishing a simple distribution network model.

Hybrid classifier for fault location in active distribution networks

This paper presents a fast hybrid fault location method for active distribution networks with distributed generation (DG) and microgrids. The method uses the voltage and current data from the measurement points at the main substation, and the connection points of DG and microgrids. The data is used in a single feedforward artificial neural network (ANN) to estimate the distances to fault from all the measuring points. A k-nearest neighbors (KNN) classifier then interprets the ANN outputs and estimates a single fault location. Simulation results validate the accuracy of the fault location method under different fault conditions including fault types, fault points, and fault resistances. The performance is also validated for non-synchronized measurements and measurement errors.

An edge computing method using a novel mode component for power transmission line fault diagnosis in distribution network

The commonly used fault diagnosis method of the power transmission line (PTL) is the traveling wave method which uses the traditional mode components $$\alpha $$ , $$\beta $$ and o to realize the fault type recognizing and the fault location in distribution network. However, the traditional mode components of the traveling wave method may take the value of zero that cannot provide the effective fault feature for the A-phase ground fault, or the A and B double phases short-circuit fault. Moreover, a single traditional mode component cannot recognize all the types of the faults, and the fault recognition has to use the multiple mode components that increases the complexity. To address the aforementioned issues, this paper proposes an edge computing scheme based on a novel mode component $$\gamma $$ for PTL fault diagnosis in distribution network. Firstly, the novel mode component $$\gamma $$ is fused according to the traditional mode components $$\alpha $$ and $$\beta $$ , then the propagation property of the traveling wave- $$\gamma $$ is derived. Secondly, the edge computing scheme and the PTL fault diagnosis method are designed for distribution network by using the only novel mode component $$\gamma $$ . Thirdly, the relationship table of the fault type and the boundary conditions as well as the component $$\gamma $$ expressions is derived for the fault recognition using the only traveling wave- $$\gamma $$ . In addition, the fault distance computing is explored by using the traveling wave- $$\gamma $$ . The computing is composed with the wave- $$\gamma $$ head identification using the optimal Wavelet vanishing moment parameter, and the arrival time determination, and the fault location method. To evaluate the efficiency of the proposed edge computing scheme, the simulation experiment and the laboratory tests are conducted. The simulation experiment results show that, the novel mode component $$\gamma $$ not only provides the effective fault features for all the ten types of the power transmission line faults, but also increases fault locating accuracy by the average 2.08 % compared with the methods using the traditional mode component $$\alpha $$ , $$\beta $$ and o. Meanwhile, the laboratory tests show that the edge computing method is practical.

Deep‐Belief‐Networks Based Fault Classification in Power Distribution Networks

Accurate fault classification is the premise of fault location and management study in a power distribution network. In most of the traditional fault classification methods used in power distribution network, the characteristic quantities are selected by experience, which will increase the uncertainty of fault classification results. A novel fault classification method based on deep belief networks (DBN) is proposed in this paper. Samples of fault current and voltage are preprocessed by min–max standardization and waveform splicing firstly, then they are used to train the DBN together with fault type label. Characteristic quantities of the current and voltage will be automatically extracted by the well‐trained DBN model, and the reliable fault type classification of distribution network can be realized. Simulation and experimental results show that the fault classification method is suitable for distribution network, and it has not only characteristics of obvious fault feature extraction and high fault classification accuracy, but also has good adaptability while the neutral grounding modes changing or used in power distribution network with distributed generator. © 2020 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.