CN106841890A - A kind of cross interconnected case internal fault diagnostic method based on earth current - Google Patents
A kind of cross interconnected case internal fault diagnostic method based on earth current Download PDFInfo
- Publication number
- CN106841890A CN106841890A CN201611091585.8A CN201611091585A CN106841890A CN 106841890 A CN106841890 A CN 106841890A CN 201611091585 A CN201611091585 A CN 201611091585A CN 106841890 A CN106841890 A CN 106841890A
- Authority
- CN
- China
- Prior art keywords
- unit
- current
- unbalance factor
- coefficient
- standard
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
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
- G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/10—Measuring sum, difference or ratio
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R29/00—Arrangements for measuring or indicating electric quantities not covered by groups G01R19/00 - G01R27/00
- G01R29/16—Measuring asymmetry of polyphase networks
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
- Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
- Y04S10/00—Systems supporting electrical power generation, transmission or distribution
- Y04S10/50—Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications
- Y04S10/52—Outage or fault management, e.g. fault detection or location
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
- Locating Faults (AREA)
Abstract
A kind of cross interconnected case internal fault diagnostic method based on earth current, including data acquisition unit, current coefficient K computing units, unbalance factor J computing units, Diagnostic parameters K, J synthesis obtain fault type unit.The data acquisition unit is made up of earth current collecting unit, earth current bandpass filtering unit, information recording unit.The current coefficient K computing units are made up of current data information memory cell, calculating current coefficient elements.The unbalance factor J computing units are made up of current coefficient memory cell, calculating unbalance factor unit.Described Diagnostic parameters K, J parameter list unit that comprehensively acquisition fault type unit is made up of Diagnostic parameters K, J nominal situation value, fault value, the specific fault type unit of Comprehensive Evaluation are constituted.A kind of cross interconnected case internal fault diagnostic method based on earth current of the present invention, realize three kinds of purposes of typical fault in the cross interconnected case of efficient diagnosis, external interference is small, low cost, can preferably be applied to different voltage class circuits, extends to multiloop long transmission line.
Description
Technical field
The present invention relates to field of fault detection, specifically a kind of base in power cable metal sheath cross connection grounding circuit
In the cross interconnected case internal fault diagnostic method of earth current.
Background technology
With the quickening of Chinese Urbanization pace of construction, electric power negative demand is sharply increased, underground power network lays electric power electricity
Cable road is more and more, and it is more and more long that cable run becomes, and to effectively reduce circulating current in sheath, current long cable circuit is using friendship
Fork interconnection earthed system.
Cross interconnected case easily meets with nature or human factor causing trouble in circuit, according to In Guangzhou Area fault case statistical form
It is bright, annual cross interconnected case internal fault account for cross interconnected line fault sum more than half, such as, cross interconnected case internal wiring
Mistake, coaxial cable fracture, water inlet etc. in case, after such failure occurs, it is whole cross interconnected big section in circuit equivalent circuit hair
It is raw to change, cause to flow to the earth earth current appearance exception through protective metal shell, may trigger serious if taking measures not in time
Accident.For example, the administrative 110kV cable metal jacket of certain power supply station, failure is there occurs after putting into operation 2 years, cable is checked immediately
Circuit, finds cable Main Corridor road 520m place, and cross interconnected case sheath protector punctures and burns, fault point puncture and surrounding sternly
Reheating is burnt.Ex-post analysis shows, the main protection of this cable run configuration：Current limliting quick-break；Back is protected：Composite voltage excessively stream.
Show according to operating experience and fault case, traditional protection fails effectively to avoid accident to occur in advance, normal conditions can only be for event
Barrier makes corresponding protection act.
With such rate of breakdown more and more higher, fault diagnosis is increasingly widely used in systems, around diagnosis
The research of technology is also more and more.More research at present stresses on-line monitoring system, by monitoring circulation, induced voltage on-line
Deng, it is proposed that a set of measure for grasping whole cross interconnected circuit ruuning situation, but, circulation size receives earth resistance, load
The factors such as electric current, system of laying are influenceed, and on-Line Monitor Device reliability is unstable, and easily by external interference, and whole circuit is installed
Package unit slightly shows complexity, and line cost is higher.Therefore, study a set of with avoiding external environmental interference, prevent different operating modes
The diagnostic method that change impacted, reduced line cost feature is significant.
The content of the invention
It is an object of the invention to provide a kind of cross interconnected case internal fault diagnostic method based on earth current, realize
Three kinds of purposes of typical fault in the cross interconnected case of efficient diagnosis, external interference is small, low cost, can preferably be applied to different electricity
Pressure grade circuit, extends to multiloop long transmission line.
The technical scheme that the present invention takes is；
A kind of cross interconnected case internal fault diagnostic method based on earth current, including data acquisition unit, current coefficient K
Computing unit, unbalance factor J computing units, Diagnostic parameters K, J comprehensively obtain fault type unit.
The data acquisition unit is by earth current collecting unit, earth current bandpass filtering unit, information recording unit
Composition.
The current coefficient K computing units are made up of current data information memory cell, calculating current coefficient elements.
The unbalance factor J computing units are made up of current coefficient memory cell, calculating unbalance factor unit.
Described Diagnostic parameters K, J comprehensively obtain fault type unit and are made up of Diagnostic parameters K, J nominal situation value, fault value
Parameter list unit, Comprehensive Evaluation specific fault type unit composition.
Diagnosis algorithm is as follows：
Step 1：Earth current information on earth current collecting unit collection ground wire, earth current bandpass filtering unit is born
Duty filters other harmonic components, leaves behind fundametal compoment；Information recording unit records specific line information and three-phase current data
Information；Step 2：Current data information memory cell receives the current data from information recording unit；Calculating current coefficient list
First calculating current coefficient；Current coefficient computing formula is KAB=IA/IB、KBC=IB/IC、KCA=IC/IA, IA、IB、ICConnect for three
Earth-current fundamental wave value；
Step 3：Current coefficient memory cell is except receiving three current coefficients obtained from calculating current coefficient elements
In addition, normalized current COEFFICIENT K can be in advance input into additionStandard(KStandard=1) and unbalance factor JStandard(JStandard=0), calculate uneven
Coefficient elements calculate unbalance factor, and unbalance factor computing formula is JAB=(KAB-KStandard)/KStandard、JBC=(KBC-KStandard)/
KStandard、JCA=(KCA-KStandard)/KStandard；Standard value is exactly reference value, and the data equivalent to collection are calculated and this standard value ratio
Compared with.
Step 4：Current coefficient memory cell is except receiving three current coefficients obtained from calculating current coefficient elements
In addition, normalized current COEFFICIENT K can be in advance input into additionStandard(KStandard=1) and unbalance factor JStandard(JStandard=0), calculate uneven
Coefficient elements 3.2 calculate unbalance factor；
Step 5：Diagnostic parameters K, J nominal situation value, the parameter list unit of fault value composition incorporate calculating current coefficient
Diagnostic parameters K, J that unit and calculating unbalance factor unit are obtained, and K, J value under normal circumstances, by normal value and event
Barrier value is compared, and the assessment for carrying out Diagnostic parameters is compared；
Step 6：Diagnostic parameters K, J normal value, fault value composition parameter table are integrally formed, and judge fault type；
Step 7：Specific fault type is known according to specific failure situation.
A kind of cross interconnected case internal fault diagnostic method based on earth current of the present invention, it is cross interconnected by direct measurement
Circuit two ends are directly grounded earth current on line and judge fault type, and the Diagnostic parameters that the diagnostic method is proposed can be avoided by loading
The influence that the change of the factors such as electric current, earth resistance is caused, diagnostic method is simple, workable, the degree of accuracy is high, may extend to length
Circuit, and avoid tradition on-line monitoring by big, the with high costs problem of external interference, there is the actual directive significance of stronger engineering.
A kind of cross interconnected case internal fault diagnostic method based on earth current of the present invention, realizes efficient diagnosis and intersects mutually
Three kinds of purposes of typical fault in header, external interference is small, low cost, can preferably be applied to different voltage class circuits, can
It is generalized to multiloop long transmission line.
Brief description of the drawings
Fig. 1 is schematic flow sheet of the invention.
Fig. 2 is the circuit design drawing of double loop 110kV described in embodiment.
Specific embodiment
Principle of the invention is：The cross interconnected circuit two ends of direct measurement are directly grounded earth current on line, calculate diagnosis
Two critical parameters of current coefficient and unbalance factor proposed in method, Diagnostic parameters effectively prevent load current, ground connection
Influence of the difference working conditions change such as resistance to judge accuracy, result of calculation is compared with nominal situation value, last comprehensively to comment
Sentence specific fault type.
A kind of cross interconnected case internal fault diagnostic method based on earth current, including data acquisition unit 1, current coefficient
K computing units 2, unbalance factor J computing units 3, Diagnostic parameters K, J comprehensively obtain fault type unit 4.
The data acquisition unit 1 is remembered by earth current collecting unit 1.1, earth current bandpass filtering unit 1.2, information
Record unit 1.3 is constituted.Wherein earth current collecting unit 1.1 is made up of model LZCT2-10 zero sequence current mutual inductors, ground connection
Current strap pass filtering unit 1.2 is made up of Pasternack radio frequency low pass filters, and information recording unit 1.3 is information Store list
Unit, is made up of model ZLKCFM100 data memory modules.
The current coefficient K computing units 2 are by 2.2 groups of current data information memory cell 2.1, calculating current coefficient elements
Into.Current data information memory cell 2.1 is made up of model ZLKCFM100 data memory modules, calculating current coefficient elements
2.2 is the excel forms of the built-in treatment current data of computer.
The unbalance factor J computing units 3 are by current coefficient memory cell 3.1,3.2 groups of calculating unbalance factor unit
Into.Current coefficient memory cell 3.1 is constituted using the data memory module with information recording unit 1.3, model
ZLKCFM100, calculates the excel forms that unbalance factor unit 3.2 is the built-in treatment current data of computer
Described Diagnostic parameters K, J comprehensively obtain fault type unit 4 by Diagnostic parameters K, J nominal situation value, fault value group
Into the specific fault type unit 4.2 of parameter list unit 4.1, Comprehensive Evaluation constitute.Diagnostic parameters K, J nominal situation value, failure
The parameter list unit 4.1 of value composition is made up of data memory module, model ZLKCFM100, the specific fault type of Comprehensive Evaluation
Unit 4.2 can write size of data comparison module by Simulink, and the calculated value of measured data and standard value are compared, and sentence
Disconnected fault type.
As shown in figure 1, a kind of cross interconnected case internal fault diagnostic method based on earth current, comprises the following steps：
Earth current information on the collection of earth current collecting unit 1.1 ground wire in B1.
Earth current bandpass filtering unit 1.2 is responsible for filtering other harmonic components in B2, leaves behind fundametal compoment and information
Recording unit 1.3 records specific line information and three-phase current data message.
Current data information memory cell 2.1 receives the current data from information recording unit 1.3 and calculates electricity in B3
The stream calculating current coefficient of coefficient elements 2.2.
Current coefficient memory cell 3.1 is except receiving three electric currents obtained from calculating current coefficient elements 2.2 in B4
Beyond coefficient, normalized current COEFFICIENT K can be in advance input into additionStandard(KStandard=1) and unbalance factor JStandard(JStandard=0), calculate not
Coefficient of balance unit 3.2 calculates unbalance factor.
Diagnostic parameters K, J nominal situations value, the parameter list unit 4.1 of fault value composition incorporate calculating current coefficient in B5
Diagnostic parameters K, J that unit 2.2 and calculating unbalance factor unit 3.2 are obtained, and K, J value under normal circumstances, will be normal
Value is compared with fault value, and the assessment for carrying out Diagnostic parameters is compared.
Diagnostic parameters K, J normal value, fault value composition parameter table are integrally formed in B6, and judge fault type.
Specific fault type is known according to specific failure situation in B7.
Earth current information on the collection ground wire of step B1 earth currents collecting unit 1.1；Earth current bandpass filtering list
Unit 1.2 is responsible for filtering other harmonic components, leaves behind fundametal compoment；Information recording unit 1.3 records specific line information and three
Phase current data message.
Step B2 current datas information memory cell 2.1 receives the current data from information recording unit 1.3；Calculate electricity
The stream calculating current coefficient of coefficient elements 2.2, current coefficient computing formula is KAB=IA/IB、KBC=IB/IC、KCA=IC/IA, IA、
IB、ICIt is three-phase ground current first harmonics value.
Step B3 current coefficients memory cell 3.1 is except receiving three electricity obtained from calculating current coefficient elements 2.2
Beyond stream coefficient, normalized current COEFFICIENT K can be in advance input into additionStandard(KStandard=1)；Unbalance factor unit 3.2 is calculated to calculate not
Coefficient of balance J, unbalance factor computing formula is JAB=(KAB-KStandard)/KStandard、JBC=(KBC-KStandard)/KStandard、JCA=(KCA-
KStandard)/KStandard。
Current coefficient memory cell 3.1 is except receiving three obtained from calculating current coefficient elements 2.2 in step B4
Beyond current coefficient, normalized current COEFFICIENT K can be in advance input into additionStandard(KStandard=1) and unbalance factor JStandard(JStandard=0), meter
Calculate unbalance factor unit 3.2 and calculate unbalance factor.
Diagnostic parameters K, J nominal situations value, the parameter list unit 4.1 of fault value composition incorporate calculating current coefficient in B5
Diagnostic parameters K, J that unit 2.2 and calculating unbalance factor unit 3.2 are obtained, and K, J value under normal circumstances, will be normal
Value is compared with fault value, and the assessment for carrying out Diagnostic parameters is compared.
B6 is integrally formed Diagnostic parameters K, J normal value, fault value composition parameter table, and judges fault type.
B7 knows specific fault type according to specific failure situation.
Table 1
By table 1, current coefficient K can effectively differentiate coaxial cable fracture defect, and determine failure phase, failure phase
Current coefficient is 0；Transposition failure, shows that three-phase current coefficient difference is larger, and biphase current coefficient is smaller, and less than 1, a phase
Current coefficient is larger, more than 2；Water inlet in case, current coefficient is in 1 or so, one case three current coefficient difference of water inlet failure
It is big compared with two casees water inlet failures.In view of current coefficient not necessarily effectively careful can distinguish cross interconnected case flooded condition, with K standards
On the basis of, propose that unbalance factor is diagnosed to fault type.Found by the unbalance factor J in table 1, one case J of water inlet
More than two casees water inlets, J values difference is larger.Effectively careful differentiation in cross interconnected case can be intake by unbalance factor.Set up
Judgment criteria can judge three kinds of failures in case.
As a example by with reference to certain power supply administration's actual motion double loop 110kV circuit, line condition is as shown in Figure 2.With reference to upper
Mask body implementation steps 1-7 is described in detail.
Whole line condition is as follows：Four cross interconnected casees are installed in center section altogether, and circuit two ends are directly grounded, pass through
Four cross interconnected case ground connection electric currents in PMS Condition Monitoring Units monitoring A1, A2, A3, A4 joint well.Table 2 provides portion
Divide Monitoring Data.
Table 2 surveys earth current
Whole southern area May continues a large amount of rainfalls, and each regional large area is disaster-stricken serious, power transmission state monitoring
Center operator on duty has found that 110kV circuit A3 well cable sheath circulation on-Line Monitor Device is alerted by PMS Condition Monitoring Units.
Through examining on the spot discovery, mutual header major part has been submerged by water in the well, and casing outside has obvious rusty stain, is in other wells
Normal condition.The circuit two-terminal-grounding line current broken down using tong ammeter field monitoring, data such as table 3.
Table 3 surveys earth current
Learnt by table 2, table 3, electric current maintains essentially in 5A or so under nominal situation, current coefficient and unbalance factor are distinguished
It is 1 and 0.Once broken down in case, one case all water inlet in such as this example, now three current coefficient sizes are left 1
The right side, and unbalance factor, more than 20%, unbalance factor difference is larger.By it is proposed by the present invention with current coefficient and not
Coefficient of balance can judge the failure by head end earth current in time for the diagnostic method of criterion.
Claims (1)
1. a kind of cross interconnected case internal fault diagnostic method based on earth current, it is characterised in that：Including data acquisition unit
（1）, current coefficient K computing units（2）, unbalance factor J computing units（3）, Diagnostic parameters K, J comprehensively obtain fault type list
Unit（4）；The data acquisition unit（1）By earth current collecting unit（1.1）, earth current bandpass filtering unit（1.2）, letter
Breath recording unit（1.3）Composition；The current coefficient K computing units（2）By current data information memory cell（2.1）, calculate
Current coefficient unit（2.2）Composition；The unbalance factor J computing units（3）By current coefficient memory cell（3.1）, calculate
Unbalance factor unit（3.2）Composition；Described Diagnostic parameters K, J comprehensively obtain fault type unit（4）By Diagnostic parameters K, J just
Normal operating mode value, the parameter list unit of fault value composition（4.1）, the specific fault type unit of Comprehensive Evaluation（4.2）Composition；
Diagnosis algorithm is as follows：
Step 1：Earth current collecting unit（1.1）Earth current information, earth current bandpass filtering unit on collection ground wire
（1.2）Duty filters other harmonic components, leaves behind fundametal compoment；Information recording unit（1.3）Record specific line information and three
Phase current data message；
Step 2：Current data information memory cell（2.1）Receive and come from information recording unit（1.3）Current data；Calculate electricity
Stream coefficient elements（2.2）Calculating current coefficient；Current coefficient computing formula is KAB=IA/IB、KBC=IB/IC、KCA=IC/IA, IA、IB、
ICIt is three-phase ground current first harmonics value；
Step 3：Current coefficient memory cell（3.1）Calculating current coefficient elements are come from except receiving（2.2）Three electricity for obtaining
Beyond stream coefficient, normalized current COEFFICIENT K can be in advance input into additionStandardWith unbalance factor JStandard, calculate unbalance factor unit
（3.2）Unbalance factor is calculated, unbalance factor computing formula is JAB=（KAB-KStandard）/KStandard、JBC=（KBC-KStandard）/KStandard、JCA=
（KCA-KStandard）/KStandard；
Step 4：Current coefficient memory cell（3.1）Calculating current coefficient elements are come from except receiving（2.2）Three electricity for obtaining
Beyond stream coefficient, normalized current COEFFICIENT K can be in advance input into additionStandardWith unbalance factor JStandard, calculate unbalance factor unit
（3.2）Calculate unbalance factor；
Step 5：The parameter list unit of Diagnostic parameters K, J nominal situation value, fault value composition（4.1）Incorporate calculating current coefficient
Unit（2.2）With calculating unbalance factor unit（3.2）Diagnostic parameters K, the J for obtaining, and K, J value under normal circumstances, will
Normal value is compared with fault value, and the assessment for carrying out Diagnostic parameters is compared；
Step 6：Diagnostic parameters K, J normal value, fault value composition parameter table are integrally formed, and judge fault type；
Step 7：Specific fault type is known according to specific failure situation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611091585.8A CN106841890B (en) | 2016-12-01 | 2016-12-01 | Fault diagnosis method in cross-connection box based on grounding current |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611091585.8A CN106841890B (en) | 2016-12-01 | 2016-12-01 | Fault diagnosis method in cross-connection box based on grounding current |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN106841890A true CN106841890A (en) | 2017-06-13 |
| CN106841890B CN106841890B (en) | 2023-05-05 |
Family
ID=59146169
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201611091585.8A Active CN106841890B (en) | 2016-12-01 | 2016-12-01 | Fault diagnosis method in cross-connection box based on grounding current |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106841890B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108152662A (en) * | 2017-11-24 | 2018-06-12 | 国网浙江省电力公司台州供电公司 | A kind of cross interconnected box fault diagnosis method and system based on earth current |
| CN110940886A (en) * | 2018-09-25 | 2020-03-31 | 长沙理工大学 | 110kV cross-connection cable fault diagnosis method based on differential current analysis |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH10232254A (en) * | 1997-02-21 | 1998-09-02 | Kanto Denki Hoan Kyokai | Instrument for measuring unbalance factor of three-phase dc voltage |
| CN103792467A (en) * | 2014-02-25 | 2014-05-14 | 国家电网公司 | High-voltage crosslinked polyethylene cable grounding current mechanism and fault analysis method |
| CN104111402A (en) * | 2014-08-01 | 2014-10-22 | 国家电网公司 | Wiring detection method and device for electric power cable cross interconnecting system |
-
2016
- 2016-12-01 CN CN201611091585.8A patent/CN106841890B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH10232254A (en) * | 1997-02-21 | 1998-09-02 | Kanto Denki Hoan Kyokai | Instrument for measuring unbalance factor of three-phase dc voltage |
| CN103792467A (en) * | 2014-02-25 | 2014-05-14 | 国家电网公司 | High-voltage crosslinked polyethylene cable grounding current mechanism and fault analysis method |
| CN104111402A (en) * | 2014-08-01 | 2014-10-22 | 国家电网公司 | Wiring detection method and device for electric power cable cross interconnecting system |
Non-Patent Citations (2)
| Title |
|---|
| 张锴: "高压交联聚乙烯电缆接地电流机理与故障分析" * |
| 柴玉华等: "基于接地电流高压电缆交叉互联故障分析" * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108152662A (en) * | 2017-11-24 | 2018-06-12 | 国网浙江省电力公司台州供电公司 | A kind of cross interconnected box fault diagnosis method and system based on earth current |
| CN110940886A (en) * | 2018-09-25 | 2020-03-31 | 长沙理工大学 | 110kV cross-connection cable fault diagnosis method based on differential current analysis |
Also Published As
| Publication number | Publication date |
|---|---|
| CN106841890B (en) | 2023-05-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104730410B (en) | A kind of distribution line disconnection monitoring method and device based on voltage x current vector | |
| CN103782509B (en) | For detecting system, computer program and the method for the internal winding failure of synchronous generator | |
| CN103150633B (en) | Power equipment state real-time evaluation and auxiliary decision-making system | |
| CN105021953B (en) | Grounding net of transformer substation corrosion detection system and method based on earth's surface magnetic induction intensity | |
| CN101777757A (en) | Small current grounding route selection method | |
| CN104154854B (en) | Method based on Lee's Sa such as characteristic on-line monitoring winding deformation of power transformer | |
| CN207335915U (en) | A kind of cable monitoring system | |
| CN102798803B (en) | Method for detecting line fault of power distribution network | |
| CN108152662A (en) | A kind of cross interconnected box fault diagnosis method and system based on earth current | |
| CN206876762U (en) | A kind of intelligent electric energy meter for automatic identification false wiring | |
| CN106646130B (en) | A kind of active distribution network Fault Locating Method compared based on current polarity and system | |
| CN104246522A (en) | A method and an apparatus for detecting a fault in an hvdc power transmission system | |
| CN106841949A (en) | Three-phase asynchronous Ac motor stator insulation on-line monitoring method and device | |
| CN109193586A (en) | A kind of both-end HVDC transmission line differential relaying algorithm | |
| CN106546858A (en) | A kind of detection method and device of distribution network failure type based on transient state component | |
| CN106841890A (en) | A kind of cross interconnected case internal fault diagnostic method based on earth current | |
| CN107247204A (en) | The condition monitoring system and monitoring method of voltage limiter in super, extra-high voltage series compensation device | |
| CN103616616B (en) | Fault detection method for large-scale grounding grid | |
| CN111198335A (en) | Fault monitoring line selection positioning device and method based on three-phase four-wire system IT system | |
| CN102437567B (en) | Method for calculating unbalanced current of capacitor in alternating current/direct current filter | |
| CN107658860B (en) | Power distribution network system fault suppression method and device, computer storage medium and equipment | |
| CN109375120A (en) | The monitoring method of alternating current is scurried into DC power system | |
| CN106443315A (en) | Multi-information fusion-based power transformer winding deformation diagnosis method | |
| CN103675606B (en) | Bridge-type DC Line Fault monitoring alarm | |
| CN105486917A (en) | Method for detecting energy-efficient power transmission line loss and faults |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |