Location of Single Phase to Ground Faults in Distribution Networks Based on Synchronous Transients Energy Analysis

Abstract

As a result of small fault current, high level of noise and a large penetration of distributed generators (DG), in the neutral non-effectively grounded medium-voltage (MV) distribution networks, it is quite difficult to locate the faulted line section for single phase to ground faults. In this paper, using a technique based on synchronized measurements in distribution networks, a fault location method based on the analysis of the energy of the transient zero-sequence current in the selected frequency band (SFB) is proposed. The equivalent impedance of the distribution network with lateral branches is studied with an equivalent network, and the phase-frequency characteristics of the equivalent impedance are analyzed. The SFB, within which the transient energy of the faulty line section is larger than that of the healthy line sections is determined. A combined fault-section location criterion is proposed and the implementation scheme is illustrated with the distribution level phasor measurement units. Numerical simulations of the IEEE 34 node system and the field experiments of a 10kV distribution network validate the feasibility and effectiveness of the proposed method.Index Terms--Active distribution networks, fault location, neutral non-effectively grounded system, single phase to ground faults, transient zero-sequence current.

Single-Line-to-Ground Fault Location in Resonant Grounded Systems Based on Fault Distortions

“…In [2], the Peterson coil was adjusted after faults to make the zero-sequence current (ZSC) on faulty feeder upstream (FFU) exceed a threshold, so as to locate the faults. In [3], a method based on instantaneous ZSC energy was proposed, which detects the faulty feeder according to the feature of maximum instantaneous ZSC energy in the selected frequency band on the faulty feeder. In [4], the average data distribution deviation of instantaneous ZSC was used to detect the faulty feeder.…”

Clarke Transformation Solution of Asymmetrical Transients in Three-Phase Circuits

“…whereas by eliminating I a in Equation (25) and by taking into account that from Equation (24), we have…”

“…A comparable analytical contribution is not available in the relevant literature, whereas the literature concerning the numerical simulation of transients in three-phase systems is vast (e.g., see [7,[18][19][20][21][22]). In particular, time-domain and frequency-domain analysis of asymmetrical transients has proved to be effective in the characterization of faults in electrical machines, power lines, and power electronics systems [23][24][25][26][27][28][29][30][31][32]. Therefore, the analytical results derived in this paper can provide theoretical support to both existing and new methodologies for fault characterization.…”

Principle of Flexible Ground-Fault Arc Suppression Device Based on Zero-Sequence Voltage Regulation

“…Additionally, the grounded electrified wire will threaten livestock and human-beings' safety, or ignite the shrubs, which may endanger public and personnel safety, causing serious social impacts and economic losses [2]. To constrain the SLG fault current, resonant grounded systems have been adopted in China and Europe [3][4], and the ability of total fault current elimination is emphasized in practice [5].…”