Analysis of the Possibilities of Selective Detection of a Single Line-to-Ground Fault in a Medium Voltage Network with Isolated Neutral

The paper analyses how the characteristics of the medium-voltage network with insulated neutral and the conditions under which the single line-to-ground fault occurs (insulation condition and value of the fault resistance) influence the zero-sequence components of the voltage of the transformer stat...

Full description

Saved in:
Bibliographic Details
Published in:Energies (Basel) 2021-11, Vol.14 (21), p.7019
Main Authors: Toader, Dumitru, Vintan, Maria, Solea, Claudiu, Vesa, Daniela, Greconici, Marian
Format: Article
Language:English
Subjects:
Distortion
Electric potential
Insulation
Mathematical models
networks with isolated neutral
Nondestructive testing
power distribution systems
Power lines
single line-to-ground faults
symmetrical components
Voltage
Waveforms
Wavelet transforms
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The paper analyses how the characteristics of the medium-voltage network with insulated neutral and the conditions under which the single line-to-ground fault occurs (insulation condition and value of the fault resistance) influence the zero-sequence components of the voltage of the transformer station medium-voltage bus bar, the fault current, the currents of the faulted line and the currents of the other non-faulted power lines connected to the transformer station bus bars. Assuming the waveform of the medium voltage bus voltages in the transformer station is known, the influence of the fault resistance on the total distortion coefficient of the fault current is analysed. This establishes the conditions under which a single line-to-ground fault can be detected by controlling the total distortion coefficient of the fault current and the currents of the fault-free lines. It also examines the conditions under which a single line-to-ground fault can be selectively detected by checking the effective value and direction of flow of the zero-sequence currents of the medium-voltage lines during the fault. The results obtained by the calculation were verified experimentally in the medium voltage network considered in the study. The acceptable differences, considering the degree of accuracy with which the parameters of a medium voltage network are known, between the results obtained by calculation and those obtained experimentally show that the simplifying assumptions accepted for the mathematical models used in the calculation are correct.
ISSN:1996-1073
1996-1073
DOI:10.3390/en14217019