Fault location in a transmission line

Patent metadata

Field	Value
Publication number	US-11079422-B2
Application number	US-201716082322-A
Country	US
Kind code	B2
Filing date	Mar 17, 2017
Priority date	Mar 17, 2016
Publication date	Aug 3, 2021
Grant date	Aug 3, 2021

Abstract

System and method for locating a fault on a line comprises a sampler that samples a pulse from the fault, the sampling being carried out at a predetermined sampling rate. A differentiator produces a differential or derivative of the pulse, and an analyzer obtains timing information from the derivative, from which it is possible to locate the fault knowing the total length of the line and the wave propagation rate.

First claim

What is claimed is:

1. System for locating a fault on a line, the line having a first end and a second end and a first direction being from said first end to said second end, the system comprising:
a first sampler configured to sample a pulse, the pulse emanating from a fault, the pulse being in a second direction opposite said first direction, the sampling being at a predetermined sampling rate;
a differentiator configured to produce a differential of said sampled pulse;
an analyzer configured to analyze said differential to obtain a timing, therefrom to determine a location of said fault.

2. The system of claim 1 further comprising a second sampler at said second end, configured to sample said pulse at said second end.

3. The system of claim 2 , configured to find a location of said fault as a proportion based on half of a time taken by said pulse to arrive at said first sampler compared with a time taken by the pulse to arrive at said second sampler.

4. The system of claim 1 , wherein said predetermined sampling rate is in the gigahertz range.

5. The system of claim 2 , wherein a distance from said first end to said second end, d, is known, a distance d 1 from said first end to a fault is unknown and a distance from said fault to said second end, being d 2 =d−d 1 , is also unknown, a time of arrival of said pulse is t 1 , a time of arrival of said pulse at said second end is t 2 , and a propagation velocity of said pulse over said line v is known, the analyzer being configured to calculate Δt=t 2 −t 1 and d 1 =½(d−νΔt) thereby to locate said fault.

6. The system of claim 1 , wherein a distance from said first end to said second end, d, is known, a distance d 1 from said first end to a fault is unknown and a distance from said fault to said second end, being d 2 =d−d 1 , is also unknown, a time of arrival of said pulse is t 1 relating to distance d 1 , a time of arrival of an echo of said pulse from said second end is t 2 relating to a distance (d 1 +2d 2 ), and a propagation velocity of said pulse over said line v is known, the analyzer being configured to locate said fault.

7. The system of claim 1 , wherein a distance from said first end to said second end, d, is known, said fault being at said first end, a distance d 1 from said fault at said first end to said sensor is unknown, a distance d 2 from said sensor to said second end is known, a time of arrival of said pulse is t 1 relating to distance d 1 , a time of arrival of a first echo of said pulse from said fault is t 2 relating to a distance (d 1 +2d 2 ), and a propagation velocity of said pulse over said line v is known, the analyzer being configured to locate said fault.

8. The system of claim 5 , wherein said predetermined inter sampling duration is 2/v and said sampling rate is v/2.

9. The system of claim 1 , wherein said first sampler is configured to sample one member of the group consisting of current and voltage.

10. The system of claim 1 wherein the line is one member of the group consisting of:
an electrical transmission line, the fault being a short circuit;
a transverse electromagnetic wave (TEM) transmission line;
an optical line wherein the fault is a break in the optical line;
a pipe, said pulse being an acoustic pulse and said fault being a break in the pipe.

11. The system of claim 1 , wherein said first sampler is configured to obtain a plurality of successive samples.

12. The system of claim 11 , wherein said plurality of successive samples are placed in a fixed size buffer with oldest samples being deleted to make way for new samples.

13. The system of claim 1 comprising a control center, the control center having links to a plurality of sources and a plurality of samplers on a plurality of lines.

14. Method for locating a fault on a line, the line having a first end and a second end and a first direction being from said first end to said second end, the method comprising:
sampling a pulse, in a second direction opposite said first direction, the pulse issuing from said fault, the sampling being at a predetermined sampling rate;
obtaining a differential of said sampled pulse;
analyzing said differential to obtain a timing, therefrom to determine a location of said fault.

15. The method of claim 14 , further comprising sampling said pulse at said second end.

16. The method of claim 15 , further comprising finding a location of said fault as a proportion based on half of a time taken by said pulse to arrive at said first end compared with a time taken by the pulse to arrive at said second end.

17. The method of claim 15 , wherein a distance from said first end to said second end, d, is known, a distance d 1 from said first end to a fault is unknown, a distance from said fault to said second end is d−d 1 and also is unknown, a time of arrival of said reflection is t 1 , a time of arrival at said pulse at said second end is t 2 , and a propagation velocity of said pulse over said line, v, is known, the analyzer being configured to calculate Δt=t 2 −t 1 and d 1 =½(d−νΔt) thereby to locate said fault.

18. The method of claim 14 , wherein a distance from said first end to said second end, d, is known, a distance d 1 from said first end to a fault is unknown and a distance from said fault to said second end, being d 2 =d−d 1 , is also unknown, a time of arrival of said pulse is t 1 relating to distance d 1 , a time of arrival of an echo of said pulse from said second end is t 2 relating to a distance (d 1 +2d 2 ), and a propagation velocity of said pulse over said line v is known, the method thereby locating said fault.

19. The method of claim 14 , wherein a distance from said first end to said second end, d, is known, a distance d 1 from a fault at said first end to said sensor is unknown, and a distance d 2 from said sensor to said second end is known, a time of arrival of said pulse is t 1 relating to distance d 1 , a time of arrival of a first echo of said pulse from said fault is t 2 relating to a distance (d 1 +2d 2 ), and a propagation velocity of said pulse over said line v is known, the method thereby locating said fault.

20. The method of claim 14 , wherein a predetermined inter-sampling duration is 2/v and said sampling rate is v/2.

21. The method of claim 14 , wherein the line is one member of the group consisting of:
an electrical transmission line and the fault comprises a short circuit;
an optical line and the fault is a break in the optical line;
a pipe, said pulse being an acoustic pulse and said fault being a break in the pipe.

22. The method of claim 14 , comprising sampling one member of the group consisting of current and voltage.

23. The method of claim 14 , comprising controlling a plurality of lines from a control center, by sending pulses and sampling on any of said lines where a fault needs to be identified.

Assignees

• Ariel Scient Innovations Ltd

Inventors

• Pinhasi Yosef
• Yahalom Asher

Classifications

• H04B17/00

  Monitoring; Testing (of line transmission systems H04B3/46; arrangements for monitoring or testing transmission systems employing electromagnetic waves other than radio waves H04B10/07) · CPC title

• H04B3/46

  Monitoring; Testing · CPC title

• G01R31/08 Primary

  Locating faults in cables, transmission lines, or networks · CPC title

• G01R31/088 Primary

  Aspects of digital computing · CPC title

• G01R31/085

  in power transmission or distribution lines, e.g. overhead · CPC title