WO1998037427A1 - Method and device for detecting and locating irregularities in a dielectric - Google Patents
Method and device for detecting and locating irregularities in a dielectric Download PDFInfo
- Publication number
- WO1998037427A1 WO1998037427A1 PCT/NL1998/000111 NL9800111W WO9837427A1 WO 1998037427 A1 WO1998037427 A1 WO 1998037427A1 NL 9800111 W NL9800111 W NL 9800111W WO 9837427 A1 WO9837427 A1 WO 9837427A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- time
- voltage
- voltage changes
- conductor
- irregularity
- Prior art date
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/08—Locating faults in cables, transmission lines, or networks
- G01R31/081—Locating faults in cables, transmission lines, or networks according to type of conductors
- G01R31/083—Locating faults in cables, transmission lines, or networks according to type of conductors in cables, e.g. underground
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/08—Locating faults in cables, transmission lines, or networks
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
- G01R31/1227—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing of components, parts or materials
- G01R31/1263—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing of components, parts or materials of solid or fluid materials, e.g. insulation films, bulk material; of semiconductors or LV electronic components or parts; of cable, line or wire insulation
- G01R31/1272—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing of components, parts or materials of solid or fluid materials, e.g. insulation films, bulk material; of semiconductors or LV electronic components or parts; of cable, line or wire insulation of cable, line or wire insulation, e.g. using partial discharge measurements
Definitions
- the present invention relates to a method and device for detecting and locating irregularities in the dielectric around a conductor, wherein the conductor is substantially elongate.
- the irregularities in the dielectric around a conductor can cause so-called partial discharges. These can occur for instance in the dielectric material situated between a core and an earth sheath of a cable.
- the partial discharges can result in loss of quality of the cable. Partial discharges are moreover often the precursor of complete discharges, or breakdown, whereby the cable becomes defective.
- WO 94/10579 is a method and device for detecting partial discharges occurring in a cable, in which the earth sheath of the cable has a helical structure, wherein on one side of the cable at least one detection coil is arranged around the cable for detecting electromagnetic voltage changes which displace along the cable.
- the voltage changes which are generated by possible partial discharges and which are propagated in both directions of the conductor from the position of the partial discharge, are detected and analyzed. Use is made herein of so-called end reflections of the voltage changes on the outer ends of the cable.
- the detection coil will first detect the direct voltage change which is transmitted directly from the position of the partial discharge to the detection coil.
- the detection coil will then detect the indirect voltage changes which are transmitted from the position of partial discharge to the detection coil via a reflection against an end of the cable.
- the path length difference between the direct and indirect pulse can be determined.
- the position of the partial discharge can be determined in accurate manner from the computed path length difference and the already known total length of the cable. This method does however have a number of significant drawbacks.
- the indirect voltage change often arrives at the detector in the "tail" of the direct voltage change and moreover the indirect voltage change often has a smaller amplitude than the direct voltage change, the indirect voltage change can often not be recognized, or only with great difficulty.
- analysis of the measurements cannot be automated and that the analysis must be performed by highly qualified and highly trained personnel. This, however, entails high cost.
- the object of the present invention is to provide a method and device with which, either in manual or automated manner, the positions of irregularities in conductors can be simply determined. This object is achieved in the manner described below.
- measuring takes place on both sides of the conductor.
- the direct voltage changes arriving on both sides are analyzed.
- the indirect, i.e. reflected, voltage changes arriving on both sides are not taken into consideration.
- a very accurate time registration is required.
- a plurality of (preferably all) branches of the cable are herein provided with voltage detection means.
- the positions of the irregularities can be determined in a manner wholly analogous to that described above .
- Figure 1 shows a schematic view of the measurement configuration wherein the method of the present invention is used.
- Figure 2 shows the voltage progression measured by the two detectors 6 and 7 before synchronization of the voltage progression using the measured time labels.
- Figure 3 shows the voltage progression measured by the two detectors 6 and 7 after synchronization using the time labels.
- Figure 4 shows a schematic view of the measurement configuration in a branched cable, i.e. a configuration with more than two detection means.
- Figure 5 shows the voltage progression measured by the detectors 9 to 13 after synchronization using the time labels.
- Figure 6 shows a further embodiment of the present invention.
- the method according to the present invention is used to test for irregularities the dielectric of conductors with earth shields or cables .
- Shown by way of example in figure 1 is a high-voltage cable 1, the length of which can vary from 10 m to 10 km and the voltage from 1 kV to 400 kV.
- the high-voltage cable is formed from a core 2 and an earth sheath 3 with a dielectric material 4 therebetween.
- Protective jacket 5 is arranged round earth sheath 3.
- the measurements according to the invention are performed by detecting means 6 and 7, which consist for instance of capacitive dividers (high-ohmic for the power supply, low-ohmic for the discharge signals) and oscilloscopes.
- the cable is connected to a high-voltage source 8.
- the position of the irregularity can be determined on the basis of a correct time labelling, possible correction for the position of the oscilloscopes and the lengths of the (branches) of the cable 1 known beforehand.
- FIG. 6 shows a further embodiment of the method according to the present invention.
- a cable 14 for testing contains three cable cores 15, 16 and 17.
- Cable core 15 is connected to a high-voltage generator 18 which generates a voltage with a voltage level preferably between 1 kV and 41 kV and a frequency preferably between 0 1 and 200 Hertz.
- the cable cores 15, 16 and 17 are connected to a coupling network 19
- the cable cores 15, 16 and 17 are connected to coupling network 29 and at the end of a branch of cable 14 the cable cores are connected to coupling network 24.
- On coupling network 19 are arranged respectively a data communication system 20, an oscilloscope or digitizer 21 and a GPS reception station 22.
- the method for measuring the partial discharge which is based on triggering of the oscilloscope or digitizer on the arrival of a discharge pulse, preferably comprises of:
- Data communication preferably takes place via the other two unused cable cores 16 and 17 or via transmitter-receivers (not shown) provided at the measurement positions;
- the voltage pulses caused by a partial discharge arrive at different points in time at the deployed measuring systems, wherein via coupling networks 19, 24 and 29 the voltage pulses are measured by oscilloscopes 22, 27, 32 and the voltage pulses are preferably stored on computers 23, 28, 33;
- Universal Time Coordinates contain inter alia information about the degree of longitude and latitude, altitude and absolute time.
- An alternative preferred embodiment for performing the method of the invention consists of simultaneously carrying out one or more registrations . Simultaneously is understood to mean that all digitizers or oscilloscopes perform a registration from exactly the same moment. For a pre-determined time period (for instance 0.5 or 2 seconds) measurement data is stored in computers 23, 28 and 33. Performing a registration at exactly the same moment is made possible by reading out the degree of longitude and latitude, altitude and absolute time of GPS reception stations 22, 27, 32 and by control using computers 23, 28 and 33.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Locating Faults (AREA)
- Testing Relating To Insulation (AREA)
- Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
- Position Fixing By Use Of Radio Waves (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
- Paper (AREA)
- Measurement Of Resistance Or Impedance (AREA)
- Length-Measuring Devices Using Wave Or Particle Radiation (AREA)
Abstract
Description
Claims
Priority Applications (11)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
RU99120296/09A RU99120296A (en) | 1997-02-24 | 1998-02-24 | METHOD FOR DETECTING AND DETERMINING THE LOCATION OF INHOMOGENEITIES IN DIELECTRIC AND A DEVICE FOR ITS IMPLEMENTATION |
JP53651598A JP2001513194A (en) | 1997-02-24 | 1998-02-24 | Method and apparatus for detecting and locating irregularities in a dielectric |
US09/380,029 US6366095B1 (en) | 1997-02-24 | 1998-02-24 | Method and device for detecting and locating irregularities in a dielectric |
EP98908311A EP1012612B1 (en) | 1997-02-24 | 1998-02-24 | Method and device for detecting and locating irregularities in a dielectric |
AT98908311T ATE248376T1 (en) | 1997-02-24 | 1998-02-24 | METHOD AND DEVICE FOR DETECTING AND LOCALIZING IRREGULARITIES IN A DILECTRIC |
AU66371/98A AU728299B2 (en) | 1997-02-24 | 1998-02-24 | Method and device for detecting and locating irregularities in a dielectric |
CA002282605A CA2282605A1 (en) | 1997-02-24 | 1998-02-24 | Method and device for detecting and locating irregularities in a dielectric |
IL13157198A IL131571A0 (en) | 1997-02-24 | 1998-02-24 | Method and device for detecting and locating irregularities in a dielectric |
BR9807749-0A BR9807749A (en) | 1997-02-24 | 1998-02-24 | Process and device for detecting and locating irregularities in the dielectric |
DE69817586T DE69817586T2 (en) | 1997-02-24 | 1998-02-24 | METHOD AND DEVICE FOR DETECTING AND LOCALIZING IRREGULARITIES OF A DIELECTRIC |
NO994085A NO994085L (en) | 1997-02-24 | 1999-08-24 | Detection of dielectric defects |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
NL1005349A NL1005349C2 (en) | 1997-02-24 | 1997-02-24 | Method and device for detecting and locating irregularities in a dielectric. |
NL1005349 | 1997-02-24 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1998037427A1 true WO1998037427A1 (en) | 1998-08-27 |
Family
ID=19764473
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/NL1998/000111 WO1998037427A1 (en) | 1997-02-24 | 1998-02-24 | Method and device for detecting and locating irregularities in a dielectric |
Country Status (17)
Country | Link |
---|---|
US (1) | US6366095B1 (en) |
EP (1) | EP1012612B1 (en) |
JP (1) | JP2001513194A (en) |
KR (1) | KR20000075664A (en) |
CN (1) | CN1251654A (en) |
AT (1) | ATE248376T1 (en) |
AU (1) | AU728299B2 (en) |
BR (1) | BR9807749A (en) |
CA (1) | CA2282605A1 (en) |
DE (1) | DE69817586T2 (en) |
ID (1) | ID23651A (en) |
IL (1) | IL131571A0 (en) |
NL (1) | NL1005349C2 (en) |
NO (1) | NO994085L (en) |
PL (1) | PL335326A1 (en) |
RU (1) | RU99120296A (en) |
WO (1) | WO1998037427A1 (en) |
Cited By (7)
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---|---|---|---|---|
CN102901912A (en) * | 2012-10-10 | 2013-01-30 | 国家电网公司 | Local discharge monitoring method for multiple intensively arranged power equipment |
CN102901914A (en) * | 2012-10-10 | 2013-01-30 | 国家电网公司 | Partial discharge monitoring method for distributed arrangement of multiple power equipment |
CN102901913A (en) * | 2012-10-10 | 2013-01-30 | 国家电网公司 | Partial discharge synchronous monitoring method for multiple electrical equipment of substation |
WO2016142205A1 (en) * | 2015-03-11 | 2016-09-15 | Dehn + Söhne Gmbh + Co. Kg | Method for determining states and locating faults in installed isolated down conductors in the external lightning protection means |
EP3106888A1 (en) * | 2015-06-15 | 2016-12-21 | Seitz Instruments AG | Method and system for partial discharge measurement on a power cable |
US11125802B2 (en) | 2017-07-24 | 2021-09-21 | Maschinenfabrik Reinhausen Gmbh | Method and testing device for measuring partial discharge pulses of a shielded cable |
US12007427B2 (en) | 2020-03-31 | 2024-06-11 | Baur Gmbh | Electrical circuit |
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KR20040079050A (en) * | 2003-03-06 | 2004-09-14 | 엘지전선 주식회사 | partial discharge locali -zation system in power cables |
US7952360B2 (en) * | 2007-03-14 | 2011-05-31 | General Electric Company | Method and system for passively detecting and locating wire harness defects |
KR100782602B1 (en) * | 2006-04-07 | 2007-12-06 | 한국원자력연구원 | Measuring apparatus for arc's striking distance using probes and measuring method thereof |
IT1393307B1 (en) | 2009-03-27 | 2012-04-20 | Techimp Technologies S A Ora Techimp Technologies S R L | DEVICE AND PROCEDURE FOR LOCALIZING PARTIAL DISCHARGES. |
IT1393308B1 (en) * | 2009-03-27 | 2012-04-20 | Techimp Technologies S A Ora Techimp Technologies S R L | DEVICE AND PROCEDURE FOR LOCALIZING PARTIAL DISCHARGES. |
EP2579056A4 (en) * | 2010-05-31 | 2017-12-13 | Universidad Politécnica De Madrid (UPM) | Novel method for real time tests and diagnosis of the sources of partial discharge in high voltage equipment and installations, which are in service or not in service, and physical system for the practical use of the method |
US9335150B2 (en) * | 2010-08-23 | 2016-05-10 | Mitsubishi Electric Corporation | Conductor length measurement device and conductor length measurement method |
DE102011009512A1 (en) * | 2011-01-26 | 2012-07-26 | Ms-Technik Mess- Und Regelungstechnik Gmbh & Co. Kg | Device for fault location |
CN102654550A (en) * | 2011-07-18 | 2012-09-05 | 张滕飞 | Method for testing cable faults by using dielectric loss change |
CN103076545B (en) * | 2012-12-31 | 2015-09-23 | 广州供电局有限公司 | The charged linear measure longimetry of high-tension cable and Partial Discharge Detection location simulation system |
CN103207358B (en) * | 2013-04-15 | 2016-02-24 | 广东电网公司佛山供电局 | High-voltage power cable nondestructive detection device |
RU2558745C1 (en) * | 2014-05-22 | 2015-08-10 | Федеральное государственное бюджетное учреждение науки Институт радиотехники и электроники им. В.А. Котельникова Российской академии наук | Method for remote detection of inhomogeneities in optically opaque media |
AT520063A1 (en) | 2017-06-02 | 2018-12-15 | Omicron Energy Solutions Gmbh | Checking a power transmission network and locating a fault in a power transmission cable |
GB2563069B (en) * | 2017-06-02 | 2020-07-01 | Ge Aviat Systems Ltd | Apparatus to detect a fault in a wire |
CN110161353A (en) * | 2019-04-30 | 2019-08-23 | 云南电网有限责任公司电力科学研究院 | A kind of fault locator and method |
CN110161358A (en) * | 2019-04-30 | 2019-08-23 | 云南电网有限责任公司电力科学研究院 | A kind of Earth design method and device |
CN110007196A (en) * | 2019-05-05 | 2019-07-12 | 华北电力大学(保定) | A method of on-line monitoring cable fault position |
DE102020116135A1 (en) | 2020-06-18 | 2021-12-23 | Westnetz Gmbh | Device and method for measuring partial discharges, and servers and methods for localizing partial discharges |
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JPH01161165A (en) * | 1987-12-16 | 1989-06-23 | Nissin Electric Co Ltd | Locating method for power transmission line accident point |
JPH06294839A (en) * | 1993-04-08 | 1994-10-21 | Fujikura Ltd | Partial discharge position detecting method for power cable |
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JP2599613B2 (en) * | 1988-03-24 | 1997-04-09 | 東北電力 株式会社 | Transmission line fault location system using artificial satellites |
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US5682100A (en) * | 1995-09-06 | 1997-10-28 | Electric Power Research Institute Inc. | System and method for locating faults in electric power cables |
US5729144A (en) * | 1996-12-02 | 1998-03-17 | Cummins; Kenneth L. | Systems and methods for determining location of a fault on an electric utility power distribution system |
-
1997
- 1997-02-24 NL NL1005349A patent/NL1005349C2/en not_active IP Right Cessation
-
1998
- 1998-02-24 AT AT98908311T patent/ATE248376T1/en not_active IP Right Cessation
- 1998-02-24 CA CA002282605A patent/CA2282605A1/en not_active Abandoned
- 1998-02-24 KR KR1019997007730A patent/KR20000075664A/en not_active IP Right Cessation
- 1998-02-24 CN CN98803798A patent/CN1251654A/en active Pending
- 1998-02-24 PL PL98335326A patent/PL335326A1/en unknown
- 1998-02-24 BR BR9807749-0A patent/BR9807749A/en not_active Application Discontinuation
- 1998-02-24 JP JP53651598A patent/JP2001513194A/en active Pending
- 1998-02-24 ID IDW991079A patent/ID23651A/en unknown
- 1998-02-24 WO PCT/NL1998/000111 patent/WO1998037427A1/en not_active Application Discontinuation
- 1998-02-24 RU RU99120296/09A patent/RU99120296A/en not_active Application Discontinuation
- 1998-02-24 IL IL13157198A patent/IL131571A0/en unknown
- 1998-02-24 AU AU66371/98A patent/AU728299B2/en not_active Ceased
- 1998-02-24 EP EP98908311A patent/EP1012612B1/en not_active Expired - Lifetime
- 1998-02-24 US US09/380,029 patent/US6366095B1/en not_active Expired - Fee Related
- 1998-02-24 DE DE69817586T patent/DE69817586T2/en not_active Expired - Fee Related
-
1999
- 1999-08-24 NO NO994085A patent/NO994085L/en not_active Application Discontinuation
Patent Citations (2)
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JPH01161165A (en) * | 1987-12-16 | 1989-06-23 | Nissin Electric Co Ltd | Locating method for power transmission line accident point |
JPH06294839A (en) * | 1993-04-08 | 1994-10-21 | Fujikura Ltd | Partial discharge position detecting method for power cable |
Non-Patent Citations (3)
Title |
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OHNO H ET AL: "DEVELOPMENT OF PARTIAL DISCHARGE LOCATOR FOR POWER CABLE", PROCEEDINGS OF THE POWER ENGINEERING SOCIETY TRANSMISSION AND DISTRIBUTION CONFERENCE, DALLAS, SEPT. 22 - 27, 1991, no. -, 22 September 1991 (1991-09-22), INSTITUTE OF ELECTRICAL AND ELECTRONICS ENGINEERS, pages 17 - 22, XP000302422 * |
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Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102901912A (en) * | 2012-10-10 | 2013-01-30 | 国家电网公司 | Local discharge monitoring method for multiple intensively arranged power equipment |
CN102901914A (en) * | 2012-10-10 | 2013-01-30 | 国家电网公司 | Partial discharge monitoring method for distributed arrangement of multiple power equipment |
CN102901913A (en) * | 2012-10-10 | 2013-01-30 | 国家电网公司 | Partial discharge synchronous monitoring method for multiple electrical equipment of substation |
WO2016142205A1 (en) * | 2015-03-11 | 2016-09-15 | Dehn + Söhne Gmbh + Co. Kg | Method for determining states and locating faults in installed isolated down conductors in the external lightning protection means |
EP3106888A1 (en) * | 2015-06-15 | 2016-12-21 | Seitz Instruments AG | Method and system for partial discharge measurement on a power cable |
US11125802B2 (en) | 2017-07-24 | 2021-09-21 | Maschinenfabrik Reinhausen Gmbh | Method and testing device for measuring partial discharge pulses of a shielded cable |
US12007427B2 (en) | 2020-03-31 | 2024-06-11 | Baur Gmbh | Electrical circuit |
Also Published As
Publication number | Publication date |
---|---|
ATE248376T1 (en) | 2003-09-15 |
KR20000075664A (en) | 2000-12-26 |
DE69817586T2 (en) | 2004-06-24 |
CN1251654A (en) | 2000-04-26 |
RU99120296A (en) | 2001-08-27 |
BR9807749A (en) | 2002-01-02 |
US6366095B1 (en) | 2002-04-02 |
AU6637198A (en) | 1998-09-09 |
NO994085L (en) | 1999-10-08 |
NO994085D0 (en) | 1999-08-24 |
AU728299B2 (en) | 2001-01-04 |
DE69817586D1 (en) | 2003-10-02 |
NL1005349C2 (en) | 1998-08-26 |
PL335326A1 (en) | 2000-04-25 |
IL131571A0 (en) | 2001-01-28 |
EP1012612B1 (en) | 2003-08-27 |
ID23651A (en) | 2000-05-11 |
EP1012612A1 (en) | 2000-06-28 |
CA2282605A1 (en) | 1998-08-27 |
JP2001513194A (en) | 2001-08-28 |
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