Showing 8 results for Fault Location
E. Kamyab, M. Javidi, J. Sadeh,
Volume 5, Issue 1 (4-2008)
Abstract
Conventional fault location methods using voltages and currents of one terminal are not applicable to multiterminal transmission lines. So far some techniques have been presented to solve fault location problem for multi-terminal transmission lines. In these methods, lumped or distributed frequency domain models of transmission lines have been used. In multi terminal lines, faulty section should be detected before fault location estimation. In this paper, a method based on time domain model of transmission line is presented to identify the faulty section and to determine the location of faults for three-terminal transmission lines. In the suggested method, samples of voltages and currents at all three terminals are used for calculating the location of the fault. The proposed algorithm is independent of fault resistance, insensitive to load current and fault inception angle. Furthermore, in the method neither any knowledge about source impedance nor the fault type classification is required. Filtering of dc and high frequency components of voltages and currents signals are not necessary. The simulation results, using EMTP/ATP and MATLAB software, confirm the accuracy and precision of the proposed method.
Dr. R. Dashti, Mr. S. M. Salehizadeh,
Volume 14, Issue 1 (6-2017)
Abstract
Power distribution feeders contains many laterals, sub-laterals, different number of circuit line, load taps, balanced and unbalanced load, different type of lines (cable or overhead), different cross-sections and numerous distribution transformers with different capacities. Moreover, the voltage and current are measured only at the beginning of the feeder. Thus, fault location is very complex. Because of lack of public electrical MV line corridors and load increasing cause to increase the double circuit lines. Consequently, locating faults in a double circuit line need to special fault-location algorithms. In this article a new method for fault location in double circuited MV power distribution lines is proposed. In this method the impedance based method is improved for locating fault in double circuit distribution networks using the precise line model. This method is tested in a 13 bus IEEE network in different conditions such as various fault resistances and different fault start angles in various distances. The results from the Matlab’s simulation show high accuracy and validity of the proposed method.
Dr. M. Ghazizadeh,
Volume 14, Issue 1 (6-2017)
Abstract
In this paper, a new method is proposed for fault location estimation in overhead-cable multi-section transmission lines. This method takes advantage of synchronized samples gathered from both terminals of the line in the time domain. Because of this, it does not need a filter to extract fundamental frequency of the voltages and currents. Thus, it shows a higher accuracy, since it is not influenced by frequency response of the filter and decaying DC component. On the other hand, this algorithm uses distributed parameter line model and consists of K+1 stages for fault location determination (K: the number of the line sections), and unlike the other methods, it does not require a recognizer to determine the faulty section of the line. The accuracy of the algorithm has been investigated by various tests, which show the high accuracy of the proposed method while different fault types occur on various locations with a variety of incidence angles.
R. Dashti, M. Ghasemi,
Volume 14, Issue 3 (12-2017)
Abstract
In this paper, an improved impedance based method has been proposed for fault location in power distribution network with presence of photovoltaic distributed generation resources. Within this method, current and voltage are measured at the beginning of feeder and at the location of distributed generation resources. The π line model is used for improving the accuracy of the suggested method. To evaluate the accuracy of the proposed method, the modified 11 node test Feeder is simulated in the Matlab software and sensitivity of the suggested method was investigated against the different fault distances fault types, fault resistances and fault inception angles. The results indicate the high accuracy of the algorithm.
M. Ghazizadeh,
Volume 14, Issue 3 (12-2017)
Abstract
In this paper, a new algorithm has been proposed for determining accurate fault distance on multi-terminal transmission lines. This method is based on genetic algorithm, and uses synchronous data recorded at all terminals, and includes two steps. In the first step, employing a comparing method, the faulty section is identified. In the second step, precise distance of the fault is found utilizing genetic algorithm. This method is more accurate compared to the previously proposed algorithms for multi-terminal transmission lines, Since it utilizes the distributed parameter line model in the time domain which fully models the capacitive characteristic of the line, and also because of employing the recorded samples at the terminals, presented harmonics in the waveforms of the terminals do not influence on the performance of the algorithm. Simulation results show high accuracy of the proposed method compared to the previously algorithms.
J. Barati, A. Droudi,
Volume 14, Issue 3 (12-2017)
Abstract
Fault location is an interesting subject in power grids. On the other hand, the application of fault current limiter (FCL) has been increasing in power network and causes some problems in operation of protection systems. This paper studies the application of FCL in power system and its effect on one-ended simple reactance fault location methods. In these methods, only voltages and currents of transmission line sending-end terminal which equipped with measuring equipment are used to estimate the fault location. Presence of FCL in the time of fault occurrence makes the existing reactance methods inaccurate and causes malfunction of fault location devices. In this paper, a new method has been proposed to improve fault location in transmission lines equipped with FCL. To evaluate the effectiveness of the proposed method, various faults on different locations of transmission lines have been applied to the simulated power grid. This method implies an irritation process to calculate the remote terminal impedance and subsequently, fault current and location. The accuracy and effectiveness of the proposed method have been proved through simulations.
Asra Izadiefar, Dr. Javad Sadeh,
Volume 21, Issue 2 (5-2024)
Abstract
The increasing development of multi-terminal high-voltage direct current (MTDC) lines due to the advantages of this type of network over the AC network, especially in long distances, has drawn more attention to providing a solution to protect and estimate the fault location in this type of network. In this paper, a method based on distributed parameters line equations is presented for fault location in an MTDC network. In the proposed method, it is assumed that the measuring instruments are installed only on the terminals connected to the converter. The proposed algorithm includes three parts: identifying the faulty pole, detecting the faulty line and estimating the fault location. To identify the faulty pole, the voltage change index is proposed. Identifying the faulty pole leads to reducing the number of times the algorithm is executed and speeding up the entire process of estimating the fault location. Faulty line detection algorithm is also divided into offline and online subsections. In the offline section, a concept called hypothetical lines is introduced according to the network structure. In the online section, using hypothetical lines and applying line equations, a method is proposed to identify faulty lines. Then using a two-ended method, the location of fault is estimated in this line. If the data is not available on at least one side of the line, it is estimated using the distributed parameter line equations. The studied network includes overhead and cable lines and radial and ring structures so that the accuracy of the proposed method can be checked in all cases. The results of the simulations show the proper performance of the proposed method for various faults, including faults near the end of long lines and faults with high resistance.
Mohammad Daisy, Dr. Hosseini Aliabadi Hosseini Aliabadi, Dr. Javadi Javadi, Dr. Hasan Meyar Naimi,
Volume 21, Issue 2 (5-2024)
Abstract
Fault location is always one of the protection requirements in direct current microgrids. The variable characteristics of currents, bi-direction load flow, and output power fluctuations in renewable sources, which cause problems for protection devices with fixed regulation, are among the challenges of these methods. Today, real-time data access in microgrids and recent developments in high-precision measurement units have become a new research milestone. In this paper, a fault location method in direct current microgrids in grid-connected mode is proposed using voltage and current measurements at the beginning and end of the section and the presence of photovoltaic and energy storage systems. In this method, using the direct current components of voltage and current and considering the π line model, in addition to the fault distance, the fault section has also been determined. Different resistances and fault locations have little effect on the performance of this algorithm. In addition, changes in line parameters and resource productions do not affect the accuracy of this method. The performance of this method was investigated using a microgrid with 8 nodes in MATLAB software and the results show the acceptable accuracy of this method.
