A Line Fault Analysis Algorithm Based on the TDR Test Algorithm

2014 ◽  
Vol 686 ◽  
pp. 371-376
Author(s):  
Hai Ye Qiao ◽  
Guang Ling Liang

The use of TDR for a single test to analyze the state of communication lines is not accurate to fault location, It also can cause the confusion of fault type and other drawbacks. This paper proposes a analysis algorithm. It can comprehensive analysis TDR test circuit fault pattern and low-frequency circuit parameters of tested line, then it determines the type and position of faults. During a time period, It tests the circuit impedance with 5-element DC model, records the values of line impedance at different times. Combining Curves of the line impedance and TDR waveforms, It accurately determines fault type of the line through the TDR test and Position of fault. By the trying It can increase the accuracy of judging failure , reduce time of repairing.

Author(s):  
Congshan Li ◽  
Ping He ◽  
Feng Wang ◽  
Cunxiang Yang ◽  
Yukun Tao ◽  
...  

Background: A novel fault location method of HVDC transmission line based on a concentric relaxation principle is proposed in this paper. Methods: Due to the different position of fault, the instantaneous energy measured from rectifier and inverter are different, and the ratio k between them is the relationship to the fault location d. Through the analysis of amplitude-frequency characteristics, we found that the wave attenuation characteristic of low frequency in the traveling wave is stable, and the amplitude of energy is larger, so we get the instantaneous energy ratio by using the low-frequency data. By using the method of wavelet packet decomposition, the voltage traveling wave signal was decomposed. Results: Finally, calculate the value k. By using the data fitting, the relative function of k and d can be got, that is the fault location function. Conclusion: After an exhaustive evaluation process considering different fault locations, fault resistances, and noise on the unipolar DC transmission system, four-machine two-area AC/DC parallel system, and an actual complex grid, the method presented here showed a very accurate and robust behavior.


2020 ◽  
Vol 10 (4) ◽  
pp. 1203 ◽  
Author(s):  
Chaichan Pothisarn ◽  
Jittiphong Klomjit ◽  
Atthapol Ngaopitakkul ◽  
Chaiyan Jettanasen ◽  
Dimas Anton Asfani ◽  
...  

This paper presents a comparative study on mother wavelets using a fault type classification algorithm in a power system. The study aims to evaluate the performance of the protection algorithm by implementing different mother wavelets for signal analysis and determines a suitable mother wavelet for power system protection applications. The factors that influence the fault signal, such as the fault location, fault type, and inception angle, have been considered during testing. The algorithm operates by applying the discrete wavelet transform (DWT) to the three-phase current and zero-sequence signal obtained from the experimental setup. The DWT extracts high-frequency components from the signals during both the normal and fault states. The coefficients at scales 1–3 have been decomposed using different mother wavelets, such as Daubechies (db), symlets (sym), biorthogonal (bior), and Coiflets (coif). The results reveal different coefficient values for the different mother wavelets even though the behaviors are similar. The coefficient for any mother wavelet has the same behavior but does not have the same value. Therefore, this finding has shown that the mother wavelet has a significant impact on the accuracy of the fault classification algorithm.


2013 ◽  
Vol 60 (9) ◽  
pp. 3784-3795 ◽  
Author(s):  
Ye Zhao ◽  
Jean-Francois De Palma ◽  
Jerry Mosesian ◽  
Robert Lyons ◽  
Brad Lehman

Fault analysis in solar photovoltaic (PV) arrays is a fundamental task to protect PV modules from damage and to eliminate risks of safety hazards. This paper focuses on line-line faults in PV arrays that may be caused by short-circuit faults or double ground faults. The effect on fault current from a maximum-power-point tracking of a PV inverter is discussed and shown to, at times, prevent overcurrent protection devices (OCPDs) to operate properly. Furthermore, fault behavior of PV arrays is highly related to the fault location, fault impedance, irradiance level, and use of blocking diodes. Particularly, this paper examines the challenges to OCPD in a PV array brought by unique faults: One is a fault that occurs under low-irradiance conditions, and the other is a fault that occurs at night and evolves during “night-to-day” transition. In both circumstances, the faults might remain hidden in the PV system, no matter how irradiance changes afterward. These unique faults may subsequently lead to unexpected safety hazards, reduced system efficiency, and reduced reliability. A small-scale experimental PV system has been developed to further validate the conclusions.


2017 ◽  
Vol 29 (13) ◽  
pp. 1116-1119 ◽  
Author(s):  
Gustavo C. Amaral ◽  
Joaquim D. Garcia ◽  
Bruno Fanzeres ◽  
Patryk J. Urban ◽  
Jean Pierre von der Weid
Keyword(s):  

Energies ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 4081 ◽  
Author(s):  
Zhengqing Han ◽  
Shuai Li ◽  
Shuping Liu ◽  
Shibin Gao

The existing fault location methods for all-parallel autotransformer railway systems (AARS) have limitations because they are generally designed for several given feeding conditions. In alternate feeding conditions, the existing fault location methods do not work well and may have large errors. To solve this problem, we have proposed a generalized fault location scheme for AARS in this paper. After analyzing the fault characteristics of AARS, we classified the feeding conditions of the faulted section of AARS into three types and introduced the corresponding fault location methods. In order to identify the faulted section and its feeding condition, we first formed a switch state matrix based on the adjacency matrix and mapped the fault current distribution into a current state matrix, then we unified the two matrices into a fault state matrix to reflect the fault state of the AARS. Finally, a generalized fault location scheme was proposed based on a fault state matrix. The proposed scheme effectively eliminates the negative influence of feeding conditions on the fault location, and it can identify the fault type and locate faults in different feeding conditions. Several simulation cases verified the effectiveness of the proposed scheme.


2014 ◽  
Vol 984-985 ◽  
pp. 996-1004
Author(s):  
D. Miruthula ◽  
Ramachandran Rajeswari

This paper presents a new method to classify transmission line shunt faults and determine the fault location using phasor data of the transmission system. Most algorithms employed for analyzing fault data require that the fault type to be classified. The older fault-type classification algorithms are inefficient because they are not effective under certain operating conditions of the power system and may not be able to accurately select the faulted transmission line if the same fault recorder monitors multiple lines. An intelligent techniques described in this paper is used to precisely detect all ten types of shunt faults that may occur in an electric power transmission system (double-circuit transmission lines) with the help of data obtained from phasor measurement unit. This method is virtually independent of the mutual coupling effect caused by the adjacent parallel circuit and insensitive to the variation of source impedance. Thousands of fault simulations by MATLAB have proved the accuracy and effectiveness of the proposed algorithm. This paper includes the analysis of fault identification techniques using Artificial Neural Network and Adaptive Neuro-Fuzzy Inference System based protection schemes. The performances of the techniques are examined for different faults on the parallel transmission line and compared with the conventional relay scheme. The results obtained shows that ANFIS based fault identification gives better performance than other techniques.


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