A method of single-ended fault location in hvdc transmission lines

Patent metadata

Field	Value
Publication number	US-2016266192-A1
Application number	US-201415030116-A
Country	US
Kind code	A1
Filing date	Oct 7, 2014
Priority date	Nov 15, 2013
Publication date	Sep 15, 2016
Grant date	—

Abstract

The invention concerns a method of fault location in HVDC (High Voltage Direct Current) transmission lines, especially in mixed lines, where part of the line is overhead line and part is a cable line. The fault location is based on estimation arrival times of travelling waves induced by fault in transmission line that are propagating along the line from faulted point to the measurement point, which is located at one end of the transmission line.

First claim

What is claimed is:

1 . A method of fault location in transmission lines especially in mixed lines, where part of the line is overhead line and part is a cable line or their combination, using measurement taken from one end of the transmission line, where after a detection a fault, times of arrival of a traveling waves pulses propagated from faulted point to the measurement point are determined in a computer device, comprises the steps:
Creation a reference database, comprising theoretical time schemes for at least first, second and third theoretical traveling wave pulses P 1 ′, P 2 ′, P 3 ′ generated in theoretical faulted points (S 3 ′) for theoretical distances (X 1 ) established by user for known line parameters and arrival times T 1 ′, T 2 ′, T 3 ′ of such pulses are calculated in the measuring point (S 1 ), Detection the presence of a traveling wave pulses from unknown real point (S 3 ) of the line for an unknown distance (X) through measuring traveling wave pulses P 1 , P 2 , P 3 in one end of the faulted line and calculation of arrival times of first T 1 , second T 2 and third T 3 of traveling wave pulses P 1 , P 2 , P 3 in a computer device for unknown distance (X) for faulted line, when a magnitude of the first pulse P 1 has a value bigger than a threshold (Th) given by the user then T 1 is equal 0, and creation a real time scheme with T 1 , T 2 , T 3 of pulses P 1 , P 2 , P 3 measured in point S 1 , comparing a real time scheme of pulses P 1 , P 2 , P 3 for unknown faulted point with all theoretical time scheme of pulses P 1 , P 2 ′, P 3 ′ for known theoretical faulted points and matching by polarity checking of real time scheme for unknown point with all theoretical time schemes, indication the known distance (X 1 ) by selecting the best matching theoretical time scheme for known distance with the real time scheme for unknown distance (X), Indication the unknown distance (X) as a value equal to the known distance (X 1 ) what determines the location of faulted point.

2 . A method according to claim 1 , characterized in that theoretical time schemes for first, second and third theoretical faulted pulses P 1 , P 2 ′, P 3 ′ generated in theoretical faulted points are based on Bewley lattice diagrams for such pulses and theoretical arrival times T 1 ′, T 2 ′, T 3 ′ calculated for theoretical known distances (X 1 ) given by user, are taken for creation theoretical time schemes.

3 . A method according to claim 1 , characterized in that the process of matching real time scheme for unknown faulted point with theoretical time schemes is based on calculating a difference (ΔT 2 k ) between the real arrival times T 2 and theoretical arrival time T 2 ′ for traveling wave of second pulses P 2 and P 2 ′, and a difference (ΔT 3 k ) between the real arrival times T 3 and theoretical arrival time T 3 ′ for traveling wave of third pulses P 3 and P 3 ′.

4 . A method according to claim 3 , characterized in that a sum (Σ(k)) of absolute values of time differences (ΔT 2 ) and (ΔT 3 ) is calculated, where (k) is an order number in the reference database.

5 . A method according to claim 4 , characterized in that the unknown distance (X) is determined by selection of a minimum value of an sum of absolute time differences (Σ(k)).

6 . A method according to claim 1 , characterized in that after the determination the unknown distance (X) an alarm is triggering for faulted point.

Assignees

• Abb Technology Ag

Inventors

• Burek Arkadiusz
• Sikorski Tomasz
• Rezmer Jacek

Classifications

• G01R31/11

  using pulse reflection methods · CPC title

• H02H7/265

  making use of travelling wave theory · CPC title

• G01R31/088

  Aspects of digital computing · CPC title

• G01R31/085 Primary

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