CN105676079B - Cable local discharge source positioning based on on-line decision rule - Google Patents

Cable local discharge source positioning based on on-line decision rule Download PDF

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CN105676079B
CN105676079B CN201510960848.3A CN201510960848A CN105676079B CN 105676079 B CN105676079 B CN 105676079B CN 201510960848 A CN201510960848 A CN 201510960848A CN 105676079 B CN105676079 B CN 105676079B
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cable
cut
temperature
source
section
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CN105676079A (en
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夏向阳
杜荣林
杨超
黄润知
贺运九
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Changsha University of Science and Technology
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Changsha University of Science and Technology
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/12Testing 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
    • G01R31/1227Testing 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
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/08Locating faults in cables, transmission lines, or networks

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Locating Faults (AREA)

Abstract

This application discloses a kind of source cable local discharge (PD) localization method based on on-line decision rule, for positioning single source PD or double sources PD in single-core cable network.PD signal energy after this method selection wavelet transformation is signal characteristic, and the Energy distribution situation at each cable connector is obtained according to this feature;And real-time monitoring is carried out to the temperature of all joints, obtain the profiling temperatures at cable connector.Then comprehensive analysis is carried out to resulting joint Energy distribution and temperature variations with three-dimensional system of coordinate, and directly determines out the position section in the source PD according to on-line decision rule.Herein described method has enough versatilities for the positioning list source PD or double sources PD, is not required to establish special database, without the relevant parameter for characteristic (position in flaw size, thickness and insulation) and cable system for considering the source PD.Even if this method is only applicable to the positioning that there is the list source PD or double sources PD cut cable, but its accuracy is very high, without synchronizing measurement to cable system.

Description

Cable local discharge source positioning based on on-line decision rule
Technical field
The present invention relates to, to a kind of localization method of Partial Discharge Sources, belong to technical field of electric power in cable system.
Background technique
In the installation process of cable system, especially medium and high pressure cable system, Condition assessment of insulation become to get over Come more important.Insulation assessment in cable system is not only to assess its operating status, and needs to assess no clear index Electric signal, such as shelf depreciation (PD), it is the dielectric level that is generated by defect and will gradually be destroyed cable.Furthermore PD can also make Generate heat at cable intermediate joint, the considerations of real-time monitoring Joint Temperature situation is also Condition assessment of insulation factor.PD phenomenon There are mainly two types of state evaluating methods for detection: online and offline.And supervisor is interested in online method, but online side Method, which will receive some factors, to be influenced, including more in noise, the interference of outer partial discharge source, 1 cut cable or multiple cut cables Influence of the melange effect, sensor in a source PD to measuring signal, partial discharge pulse are propagated and the influence of reflection.
In order to research and solve these problems in line method, the first having to do for cable system of the task is that the source PD is fixed Position, this positioning are not the accurate positioning in the source PD to be carried out for a certain section of cable, but there are the sources PD to entire cable system Cut cable positioned.Currently, most of sources PD localization method contributes to the positioning in the single source PD in individual cable section, Less the case where considering multiple sources PD.Therefore, find cable system in the localization method in the list source PD or double sources PD to cable Status assessment has a very important significance.
Summary of the invention
In order to position the single source PD or double sources PD in two sides earth single-core cable network, the present invention proposes a kind of based on online The Partial Discharge Sources localization method of decision rule.PD signal energy after this method selection wavelet transformation is signal characteristic, according to This feature obtains the Energy distribution situation at each cable connector;And real-time monitoring is carried out to the temperature of all joints, it obtains Profiling temperatures at cable connector caused by PD phenomenon.Then according to on-line decision rule to Energy distribution at cable connector Comprehensive analysis is carried out with temperature variations, directly determines out the position section in the source PD.
Technical solution provided by the invention is as follows:
The cable system, it is assumed that share m cable connector, Mk indicates connector, is divided into m-1 sections, E is indicated at cable connector Energy value, T indicate cable connector at temperature value.Each joint is measured particular by High Frequency Current Sensor (HFCT) Current signal, through wavelet transformation extract signal energy feature, obtain the Energy distribution feelings of each joint of entire cable system Condition, while measuring by temperature sensor the temperature variations of each joint.The both ends of cut cable where Partial Discharge Sources Connector has higher signal energy and temperature compared to other connectors, and considers insulation defect and transient fault to single source PD Two kinds of situations, connector temperature increases very little when transient fault.
After the Energy distribution and profiling temperatures for obtaining joint, for application on-line decision rule, first to cable In network the list source PD or double sources PD may where cut cable classify, can be divided into 4 kinds of situations: 1. two PD cut cables be separated by compared with Far (intermediate more than 1 normal reach) 2. two PD cut cables are separated by adjacent compared with nearly (only every 1 normal reach) 3. two PD cut cables 4. only 1 PD cut cable (insulation defect section or transient fault section).
Decision rule is listed to above 4 kinds of situations:
Regular 1 (two PD cut cables are relatively far apart): it if there are the larger value for the energy indexes at two pairs of separating joints, connects Head is Mn, Mn+1, Mj and Mj+1, while the temperature T of corresponding joint also has different degrees of raising, then cable system n- (n + 1) section and j- (j+1) section are cut cable where double sources PD.Otherwise next rule is used.
Rule 2 (two PD cut cables are separated by relatively close): it if there are the larger value for the energy indexes two pairs of adjacent joints, connects Head is Mn, Mn+1, Mn+2, Mn+3, while the temperature T of corresponding joint also has different degrees of raising, then cable system n- (n+1) section and the source (n+2)-(n+3) Duan Weishuan PD place cut cable.Otherwise next rule is used.
Regular 3 (two PD cut cables are adjacent): if only there are the larger value, connectors for the energy indexes 3 adjacent joints Temperature T for n, n+1, n+2, while corresponding joint also has different degrees of raising, then cable system n- (n+1) section and (n + 1)-(n+2) cut cable where the source Duan Weishuan PD.Otherwise next rule is used.
Regular 4 (single PD cut cables): if only there are the larger value, piece-ups n, n for the energy indexes 1 pair of adjacent joint + 1, while the temperature T of corresponding joint also has different degrees of raising, then cable system n- (n+1) section is defective cable Section;The temperature T of corresponding joint only has minimum raising simultaneously, then cable system n- (n+1) section is transient fault electricity Cable section.
Cut cable where positioning the list source PD or double sources PD using this method has enough versatilities, is not required to establish special Database, without consider the source PD characteristic (flaw size, thickness and position) and cable system relevant parameter.Even if should Method is only applicable to the positioning in single source PD or double sources PD cut cable, but its accuracy is very high, without synchronizing to cable system Measurement.
Detailed description of the invention
Fig. 1 is cable system benchmark model
Fig. 2 (1) and 2 (2) are signal energy at three-dimensional system of coordinate lower cable connector and temperature conditions schematic diagram wherein Fig. 2 It (1) is double sources PD and normal condition, Fig. 2 (2) is the list source PD situation (comparison of insulation defect and transient fault)
Fig. 3 is the flow chart that the source PD is positioned using on-line decision rule
Specific embodiment
The invention will be further described with specific implementation process with reference to the accompanying drawing.
Referring to Fig. 1, single-core cable grid reference model shares m cable connector as shown, setting, and is divided into m-1 electricity Cable section, and every section of cable two sides earth.Applying voltage to cable system both ends from substation runs cable system, at every section High Frequency Current Sensor and temperature sensor are installed at cable connector, wavelet transform process is carried out to current signal detected, Signal energy feature after treatment obtains Energy distribution situation, while the situation of change of real-time monitoring temperature.Wherein small echo The morther wavelet of transformation is selected as db7, and signal characteristic chooses the energy content of the 9th decomposition level, because it is by noise effect very little.
Above-mentioned resulting energy and temperature conditions are analyzed, referring to fig. 2, which is three-dimensional system of coordinate lower cable connector The signal energy and temperature conditions schematic diagram at place, wherein Fig. 2 (1) is double sources PD and normal connector situation, and Fig. 2 (2) is the list source PD Situation.Fig. 2 (1) it can be concluded that, the two end connectors energy with higher of PD cut cable occurs, and temperature becomes in higher range Change;Normal joint energy is very low, and temperature is maintained at normal value.Fig. 2 (2) it can be concluded that exist the list source PD when, joint energy Amount is higher, is the PD as caused by cable built-in electrical insulation defect if temperature is also higher;If temperature increase it is minimum, be due to PD caused by transient fault.This is because transient fault time-continuing process is very of short duration just to occur self-cleaning in insulating inner, And joint temperature could not be caused to have greatly changed.
According to the analysis of joint Energy distribution and profiling temperatures, referring to Fig. 3, it is fixed that the source PD is carried out using mentioned method Position.Detailed process are as follows: first find out compared to other higher connectors of connector energy, and comprehensive corresponding joints temperature conditions, meet Otherwise rule 1 carries out rule 2 then cable system n- (n+1) section and j- (j+1) section are double sources PD cut cable;Meet rule 2, then cable system n- (n+1) section and the source (n+2)-(n+3) Duan Weishuan PD cut cable, otherwise carry out then 3;Meet rule 3, that Otherwise cable system n- (n+1) section and the source (n+1)-(n+2) Duan Weishuan PD cut cable carry out rule 4;Meet rule 4, then Cable system n- (n+1) section is the list source PD cut cable, if connector temperature is higher, for PD caused by insulation defect;If connector Temperature rises seldom, then is PD caused by transient fault.

Claims (5)

1. a kind of cable local discharge source localization method based on on-line decision rule, which is characterized in that for positioning single electricity Single source PD or double sources PD in cable network;PD signal energy after this method selection wavelet transformation is signal characteristic, according to the spy Obtain the Energy distribution situation at each cable connector;And real-time monitoring is carried out to the temperature of all joints, it is existing to obtain PD As the profiling temperatures at caused cable connector;With three-dimensional system of coordinate to resulting joint Energy distribution and temperature point Cloth situation carries out comprehensive analysis, further in accordance with the process of on-line decision rule, directly determines out the position section in the source PD.
2. a kind of cable local discharge source localization method based on on-line decision rule according to claim 1, feature It is, every section of cable in the single-core cable network all passes through two sides earth, it is assumed that share m cable connector, Mk indicates tool Body connector, is divided into m-1 cut cable, and E indicates that the energy value at cable connector, T indicate the temperature value at cable connector;Pass through height Frequency current sensor measures the current signal of each joint, and then obtains energy value, and is measured by temperature sensor each The temperature value of joint.
3. a kind of cable local discharge source localization method based on on-line decision rule according to claim 2, feature Be, cut cable where the list source PD or the combination of double sources PD has 4 kinds of situations in single-core cable network: 1. two PD cut cables be separated by compared with Far, intermediate more than 1 normal reach;2. two PD cut cables are separated by relatively closely, only every 1 normal reach;3. two PD cut cables are adjacent; 4. only 1 PD cut cable.
4. a kind of cable local discharge source localization method based on on-line decision rule according to claim 3, feature It is, the on-line decision rule:
Relatively far apart, the case where centre is more than 1 normal reach, is using regular 1: if at two pairs of separating joints for two PD cut cables Energy indexes there are the larger value, connector Mn, Mn+1, Mj and Mj+1, while the temperature T of corresponding joint also has in various degree Raising, then single-core cable network n- (n+1) section and j- (j+1) section are cut cables where double sources PD;
Two PD cut cables are separated by relatively close, and the case where being only separated with 1 normal reach is using rule 2: if two pairs of adjacent joints There are the larger value, connector Mn, Mn+1, Mn+2 and Mn+3 for energy indexes, while the temperature T of corresponding joint also has in various degree Raising, then cut cable where single-core cable network n- (n+1) section and the source (n+2)-(n+3) Duan Weishuan PD;
The adjacent situation of two PD cut cables is using rule 3: if only 3 adjacent joints energy indexes there are the larger value, Connector is Mn, Mn+1, Mn+2, while the temperature T of corresponding joint also has different degrees of raising, then single-core cable network n- (n+1) section and the source (n+1)-(n+2) Duan Weishuan PD place cut cable;
The case where only 1 PD cut cable, is using rule 4: if only there are the larger value for the energy indexes 1 pair of adjacent joint, connecing Head is Mn, Mn+1, while the temperature T of corresponding joint also has different degrees of raising, then single-core cable network n- (n+1) section As defective cable section;The temperature T of corresponding joint only has minimum raising simultaneously, then single-core cable network n- (n+1) section As transient fault cut cable.
5. a kind of cable local discharge source localization method based on on-line decision rule according to claim 1, feature It is, the signal characteristic is PD signal by wavelet transform process, and morther wavelet is selected as db7, extracts the energy of the 9th decomposition level Measure content.
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CN109406963A (en) * 2018-11-16 2019-03-01 国网江苏省电力有限公司盐城供电分公司 A kind of the cable system Partial Discharge Detection positioning system and its detection localization method of more cut cables
CN109406964A (en) * 2018-11-16 2019-03-01 国网江苏省电力有限公司盐城供电分公司 A kind of cable system partial discharge positioning method of more cut cables

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102590716A (en) * 2012-02-11 2012-07-18 广东电网公司电力科学研究院 Power cable partial discharge signal denoising method based on wavelet analysis
CN103558517A (en) * 2013-10-29 2014-02-05 云南电网公司楚雄供电局 Method for positioning high-voltage apparatus electro-discharge source based on energy change
CN103675616A (en) * 2013-11-15 2014-03-26 华南理工大学 Online partial discharge detection signal recognition method of cable
CN104502820A (en) * 2014-12-25 2015-04-08 国家电网公司 Two-dimensional wavelet transformation based transformer partial discharge spectrum denoising method
CN104730424A (en) * 2015-03-02 2015-06-24 国家电网公司 Cable partial discharging positioning method based on self-correlation-wavelet modulus maximum analysis
CN104765971A (en) * 2015-04-23 2015-07-08 东北电力大学 Crosslinked polyethylene high-voltage cable partial discharge feature extraction method
CN104808122A (en) * 2015-04-20 2015-07-29 国家电网公司 XLPE (Cross Linked Polyethylene) cable partial discharging signal estimation method based on statistical learning theory

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000339577A (en) * 1999-05-25 2000-12-08 Sumitomo Electric Ind Ltd Method for detecting partial discharge of power cable connection part
GB0504600D0 (en) * 2005-03-04 2005-04-13 Univ Strathclyde Detecting partial discharge in high voltage cables
JP2007292700A (en) * 2006-04-27 2007-11-08 Toshiba Corp Partial discharge position specifying method of stationary induction apparatus

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102590716A (en) * 2012-02-11 2012-07-18 广东电网公司电力科学研究院 Power cable partial discharge signal denoising method based on wavelet analysis
CN103558517A (en) * 2013-10-29 2014-02-05 云南电网公司楚雄供电局 Method for positioning high-voltage apparatus electro-discharge source based on energy change
CN103675616A (en) * 2013-11-15 2014-03-26 华南理工大学 Online partial discharge detection signal recognition method of cable
CN104502820A (en) * 2014-12-25 2015-04-08 国家电网公司 Two-dimensional wavelet transformation based transformer partial discharge spectrum denoising method
CN104730424A (en) * 2015-03-02 2015-06-24 国家电网公司 Cable partial discharging positioning method based on self-correlation-wavelet modulus maximum analysis
CN104808122A (en) * 2015-04-20 2015-07-29 国家电网公司 XLPE (Cross Linked Polyethylene) cable partial discharging signal estimation method based on statistical learning theory
CN104765971A (en) * 2015-04-23 2015-07-08 东北电力大学 Crosslinked polyethylene high-voltage cable partial discharge feature extraction method

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
The study on the partial discharge and insulation aging detection of cable based on the chaotic characteristic parameter;Tao Liu et al.;《2015 5th International Conference on Electric Utility Deregulation and Restructuring and Power Technologies (DRPT)》;20151129;第1637-1642页

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