The effect of fault resistance on the earth fault characteristics in unearthed and compensated neutral medium voltage networks

2012 ◽  
Author(s):  
M. F. Abdel-Fattah ◽  
M. Lehtonen
Keyword(s):  
Neutral Medium ◽  
Medium Voltage ◽  
Earth Fault ◽  
Fault Resistance ◽  
The Earth

scholarly journals Evaluation of earth fault location algorithm in medium voltage distribution network with correction technique

2019 ◽  
Vol 9 (3) ◽  
pp. 1987
Author(s):  
N. S. B. Jamili ◽  
M. R. Adzman ◽  
S. R. A. Rahim ◽  
S. M. Zali ◽  
M. Isa ◽  
...  
Keyword(s):  
Fault Location ◽  
Distribution Network ◽  
Distance Estimation ◽  
Voltage Distribution ◽  
Medium Voltage ◽  
Earth Fault ◽  
Ground Fault ◽  
The Earth ◽  
Correction Technique ◽  
Location Algorithm

This paper focused on studying an algorithm of earth fault location in the medium voltage distribution network. In power system network, most of the earth fault occurs is a single line to ground fault. A medium voltage distribution network with resistance earthing at the main substation and an earth fault attached along the distribution network is modeled in ATP Draw. The generated earth fault is simulated, and the voltage and current signal produced is recorded. The earth fault location algorithm is simulated and tested in MATLAB. The accuracy of the earth fault location algorithm is tested at several locations and fault resistances. A possible correction technique is explained to minimize the error. The results show an improvement fault location distance estimation with minimum error.

scholarly journals Modeling Features of a Single Phase-to-Earth Fault in a Medium Voltage Overhead Transmission Line

2020 ◽  
Vol 4 (2) ◽  
pp. 127-138
Author(s):  
Ismael Saeed ◽  
Kamal Sheikhyounis
Keyword(s):  
Transmission Line ◽  
Transmission Lines ◽  
Single Phase ◽  
Single Frequency ◽  
Mathematical Representation ◽  
Medium Voltage ◽  
Overhead Transmission Line ◽  
Earth Fault ◽  
Distributed Parameters ◽  
Selection Of

The modeling and calculation of a single phase-to-earth fault of 6 to 35 kV have specific features when compared with circuits with higher nominal voltages. In this paper, a mathematical analysis and modeling of a 3-phase overhead transmission line with distributed parameters consisting of several nominal T-shaped, 3-phase links with concentrated parameters replaced by 1 nominal T-shaped link were carried out. Further analysis showed that not accounting for the distributed nature of the line parameters did not cause significant errors in the assessment of the maximum overvoltage in the arc suppression in single phase-to-earth faults, and that sufficient accuracy insures the representation of the line by only 1 nominal T-shaped, 3-phase link. Such a modeling technique makes it impossible to identify the location of single-phase faults, which is the property of higher harmonic amplification of individual frequencies. Chain equivalent schemas with constant parameters are valid for a single frequency, thereby providing an opportunity to study the nature of the wave process by the discrete selection of parameters. Next in the mathematical representation, we consider the overhead transmission lines as lines with distributed parameters.

scholarly journals Investigation of the Effects of the Arc Fault Resistance and Transient Resistance on the Overcurrent Ground Relay Protection Setting in Medium Voltage Electrical Power Lines

2020 ◽  
Vol 4 (1) ◽  
pp. 67-72
Author(s):  
Plamen Antonov Stanchev ◽  
Mediha Enver Mehmed-Hamza
Keyword(s):  
Power Transformer ◽  
Electrical Power ◽  
Relay Protection ◽  
Power Grids ◽  
Power Lines ◽  
Medium Voltage ◽  
Fault Resistance ◽  
Ground Fault ◽  
Determining Factors ◽  
Transient Voltages

In the medium voltage electrical power lines, the most common fault is the phase to ground fault. The determining factors for selection of the neutral grounding mode of the medium voltage electrical power lines are the selectivity of the relay protection, the transient voltages during phase to ground fault, the magnitude of the fault currents, etc. The paper studies the influence of the transient resistance of phase to ground fault on the selectivity and sensitivity of the earth fault protection when the neutral of the power transformer is grounded through active resistance in medium voltage power grids.

scholarly journals The influence of the network asymmetry on the settings and sensitivity of an earth fault protection using higher harmonics

2019 ◽  
Vol 84 ◽  
pp. 02008
Author(s):  
Lubomir Marciniak ◽  
Mateusz Piątek
Keyword(s):  
Reactive Power ◽  
Higher Harmonics ◽  
Medium Voltage ◽  
Earth Fault ◽  
Power Setting ◽  
Zero Sequence ◽  
The Asymmetry ◽  
Supply Voltages ◽  
Zero Sequence Voltage

Detection of high resistance earth faults in medium voltage networks is an important problem due to ineffectiveness of traditional earth fault protections. Such short circuits can be detected by the criterion of a reactive power of higher harmonics for zero sequence current and voltage. The main problem is determination of the power setting value in the protection, which depends on the asymmetry of phase-to-earth capacitances and higher harmonics in supply voltages, which are generated by non-linear loads. The intensive tests of the asymmetry of the zero sequence currents and voltages for harmonics and their reactive power have been carried out in 15 kV compensated network as a function of all relevant parameters, i.e.: maximum capacitance deviation of the network and protected line, percentage content of harmonics in supply voltages, capacitive current of the network and the line. It has been shown that third harmonics of the zero sequence voltage and current are the best suited for practical use, since the asymmetry reactive power of these components is the smallest among the considered harmonics and the protection sensitivity will be the highest.

Analysis of the Earth Fault Distance Measuring Units Algorithms Operation

2019 ◽  
Author(s):  
Tatjana Lomane ◽  
Kristina Berzina ◽  
Inga Zicmane ◽  
Sergejs Rubcovs ◽  
Renata Varfolomejeva ◽  
...  
Keyword(s):  
Earth Fault ◽  
The Earth ◽  
Distance Measuring
Sign in / Sign up

Export Citation Format

Share Document