Estimation of Line Zero Sequence Impedance using Real Field Fault Data for Fault Location Application

Author(s):  
Marian Dragomir ◽  
Anamaria Iamandi ◽  
Marcel Istrate ◽  
Alin Dragomir ◽  
Dragos Machidon
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.


Energies ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1293 ◽  
Author(s):  
Krzysztof Lowczowski ◽  
Jozef Lorenc ◽  
Jozef Zawodniak ◽  
Grzegorz Dombek

The paper analyzes the utilization of cable screen currents for earth fault identification and location. Attention is paid on cable and mixed feeders—cable and overhead lines. The principle of operation is based on utilization of 3 criterion values: Ratio of cable screen earthing current and zero sequence cable core current—RF110/15, phase shift between cable screen earthing current and zero sequence cable core current—α and cable screen admittance defined as a ratio of cable screen earthing current and zero sequence voltage—Y0cs. Earth fault location is possible thanks to discovered relation between RF110/15 and α, whereas Y0cs allows for reliable detection of earth faults. Detection and identification are very important because it allows to increase the reliability of supply—reduce downtime and number of consumers affected by the fault. The article presents a phase to ground fault current flow for different power system configurations. At the end solution, which improves location capabilities is proposed. The solution is analyzed in PSCAD software and verified by network experiment.


2014 ◽  
Vol 602-605 ◽  
pp. 2110-2113
Author(s):  
Dan Lu ◽  
Jun Qiang Liu ◽  
Xiu Gang Yin

In allusion to the low reliability and sensitivity of existing single-phase earth fault location method, this article proposed a new location method based on WAMS in mine non-effectively grounded network. It analyzed the logical relationship of zero-sequence current of each branch when single-phase earth fault occurred and deduced zero-sequence current formulae of each branch. The detailed description is given to calculating differential variable of zero-sequence current and explicating principle and realization of fault section location. The coal mine power supply model based on WAMS is introduced and the scheme was verified by simulation via MATLAB and calculation via Fast Fourier Transform. The results indicate that it avoids influences by load capacity and the voltage initial phase angle, then effectively enhances fault location reliability and sensitivity.


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