CN109829187A - A kind of assessment of high-power transformer D.C. magnetic biasing problem and administering method - Google Patents
A kind of assessment of high-power transformer D.C. magnetic biasing problem and administering method Download PDFInfo
- Publication number
- CN109829187A CN109829187A CN201811538705.3A CN201811538705A CN109829187A CN 109829187 A CN109829187 A CN 109829187A CN 201811538705 A CN201811538705 A CN 201811538705A CN 109829187 A CN109829187 A CN 109829187A
- Authority
- CN
- China
- Prior art keywords
- transformer
- current
- magnetic biasing
- neutral point
- power transformer
- 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.)
- Pending
Links
Abstract
The present invention relates to a kind of assessment of high-power transformer D.C. magnetic biasing problem and administering methods, the appraisal procedure includes: based on live actual operating mode, the AC network electricity transformer to be assessed to direct current grounding pole periphery carries out live detection, obtain measured result data, and under DC engineering monopole operating mode, when different earth currents, transformer central point current amplitude and its variation tendency；Simulation calculation is carried out based on the measured result data and transformer central point current amplitude variation tendency, judges whether simulation result exceeds prescribed limit, if so, determining that transformer has D.C. magnetic biasing.The present invention is based on the detections at scene; to assess DC line and converter station, nearby high-power transformer whether there is D.C. magnetic biasing to subsequent simulation calculation; and the transformer that there are problems that D.C. magnetic biasing is administered by series capacitance, modification protection and automatic safety device definite value are not needed after simple and practical, significant effect, installation.
Description
Technical field
The invention belongs to technical field of direct current power transmission more particularly to a kind of assessment of high-power transformer D.C. magnetic biasing problem and control
Reason method.
Background technique
Direct current transportation uses bipolar balance movement in normal conditions, and DC current is not passed through the earth at this time.Work as converter station
When failure or maintenance, when using bipolar off-center operation operating condition, it will there is DC current to pass through line residual current.DC current flows through
The earth will cause current potential between the earth and differ, and can generate DC potential difference between Liang Ge substation apart from each other.And two
The resistance of transmission line of electricity is smaller between substation, and DC current will be back to transformer and power transmission line by the neutral point being grounded
Road increases so as to cause transformer noise, vibrates the problems such as aggravation, hot-spot, generates D.C. magnetic biasing effect, drastically influence
The safe and stable operation of system.
D.C. magnetic biasing refers to the DC component in transformer, leads to transformer core half cycle magnetic saturation, and thus cause
A series of galvanomagnetic-effects.Transformer works normally under communicational aspects, and iron core magnetic flux density increases, and transformer work is magnetizing
The nonlinear region of curve, excitation current waveform are peaked wave, and positive and negative half-wave symmetry, and transformer is under D.C. magnetic biasing, direct current
It is superimposed with exchange flux, increase with the iron core degree of saturation of consistent half of the cycle in D.C. magnetic biasing direction, in addition half of cycle
Degree of saturation reduce, positive and negative half-wave asymmetrically shape is presented in corresponding excitation current waveform.D.C. magnetic biasing is transformer
A kind of abnormal operating state, since resistance characteristic is only presented to DC component in the primary side equivalent impedance of transformer, and resistance is very
It is small.Therefore, the DC component of very little will form very big DC magnetizing magnetic potential in the windings, the direct current magnetic potential with exchange magnetic potential
One reacts on transformer primary side, and the work magnetization curve of transformer core is caused to shift, and occurs about origin asymmetry,
That is transformer bias phenomenon.
The reason of causing transformer DC magnetic bias is different, mainly includes that the operation of direct current monopolar ground return and earth's magnetic field are disturbed
It is dynamic.DC transmission system in bipolar and unsymmetric or monopolar operation, will there is certain DC current to flow by earthing pole big
Ground, while not equipotential is formed in Earth Surface, at this moment DC current may enter transformer winding by transformer neutral point,
DC current is formed in transformer winding, transformer flux density operating point shifts, and so that transformer is generated D.C. magnetic biasing, seriously
Endanger the safe operation of electric system.D.C. magnetic biasing mainly has the harm of several respects: 1) transformer noise and vibration aggravation；
2) voltage waveform distortion；3) harmonic wave is generated；4) transformer reactive loss increases；5) relay protection system failure.Therefore, it is necessary to right
Transformer DC magnetic bias problem is assessed, and proposes effective resolution.
Summary of the invention
The object of the present invention is to provide a kind of assessment of high-power transformer D.C. magnetic biasing problem and administering methods, based on scene
Detection, to assess DC line and converter station, nearby high-power transformer whether there is D.C. magnetic biasing to subsequent simulation calculation, and mention
For effectively administering the scheme of D.C. magnetic biasing.
The present invention provides a kind of high-power transformer D.C. magnetic biasing problem appraisal procedures, comprising:
Step 1, based on live actual operating mode, the AC network electricity transformer to be assessed to direct current grounding pole periphery
Live detection is carried out, is obtained under measured result data and DC engineering monopole operating mode, when different earth currents, transformation
Device central point current amplitude and its variation tendency；Measured result data include test during transformer neutral point DC current,
It is multiple in transformer noise, transformer vibration data；
Step 2, simulation calculation is carried out based on the measured result data and transformer central point current amplitude variation tendency,
Judge whether simulation result exceeds prescribed limit, if so, determining that transformer has D.C. magnetic biasing.
Further, step 1 includes:
Based on live actual operating mode, direct current monopole-ground return circuit method of operation is formulated to AC network in assessment area
The testing scheme that main transformer influences.
Further, prescribed limit includes: in step 2
The permission DC current of the every phase winding of transformer are as follows: single-phase transformer is the 0.3% of rated current, and three-phase and five-pole becomes
Depressor is the 0.5% of rated current, and three-phase full-bridge converter is the 0.7% of rated current.
The present invention also provides a kind of high-power transformer D.C. magnetic biasing problem administering methods, i.e., using in transformer neutral point
The method for accessing capacitor inhibits transformer neutral point DC current, is executed using the state translation lookaside switch in parallel with capacitor straight
It is grounded the conversion of operating status and capacity earth operating status.
Further, which includes:
When transformer neutral point detects out-of-limit DC current, state translation lookaside is switched and is disconnected, into blocking
Mode；When transformer neutral point DC current disappears, delay closes the switch state translation lookaside, and recovery is directly grounded mould
Formula.
Further, the administering method further include:
Overvoltage is executed by high-power thyristor, overcurrent quickly bypasses protection act, and driving condition translation lookaside
It closes the switch and executes the movement of neutral point metallic earthing.
According to the above aspect of the present invention, by high-power transformer D.C. magnetic biasing problem assessment and administering method, based on scene detection,
To assess DC line and converter station, nearby high-power transformer whether there is D.C. magnetic biasing to subsequent simulation calculation, and pass through series connection
Capacitor administers the transformer that there are problems that D.C. magnetic biasing, and modification protection and safety are not needed after simple and practical, significant effect, installation
Automatic device definite value.
The above description is only an overview of the technical scheme of the present invention, in order to better understand the technical means of the present invention,
And can be implemented in accordance with the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention and the accompanying drawings.
Detailed description of the invention
Fig. 1 is a kind of flow chart of high-power transformer D.C. magnetic biasing problem appraisal procedure of the present invention；
Fig. 2 is that transformer DC magnetic bias In-situ test assesses schematic diagram in one embodiment of the invention；
Fig. 3 is series-capacitor transformer neutral point blocking schematic diagram in one embodiment of the invention.
Specific embodiment
With reference to the accompanying drawings and examples, specific embodiments of the present invention will be described in further detail.Implement below
Example is not intended to limit the scope of the invention for illustrating the present invention.
Join shown in Fig. 1, present embodiments provide a kind of high-power transformer D.C. magnetic biasing problem appraisal procedure, comprising:
Step S1, based on live actual operating mode, the AC network electricity transformation to be assessed to direct current grounding pole periphery
Device carries out live detection, obtains under measured result data and DC engineering monopole operating mode, when different earth currents, becomes
Depressor central point current amplitude and its variation tendency；Measured result data include transformer neutral point direct current during test
It is stream, transformer noise, multiple in transformer vibration data；
Step S2 is carried out based on emulation by the measured result data and transformer central point current amplitude variation tendency
It calculates, judges whether simulation result exceeds prescribed limit, if so, determining that transformer has D.C. magnetic biasing.
In the present embodiment, step S1 includes:
Based on live actual operating mode, direct current monopole-ground return circuit method of operation is formulated to AC network in assessment area
The testing scheme that main transformer influences.
In the present embodiment, prescribed limit includes: in step S2
The permission DC current of the every phase winding of transformer are as follows: single-phase transformer is the 0.3% of rated current, and three-phase and five-pole becomes
Depressor is the 0.5% of rated current, and three-phase full-bridge converter is the 0.7% of rated current.
The present embodiment additionally provides a kind of high-power transformer D.C. magnetic biasing problem administering method, i.e., using in transformer neutrality
The method of point access capacitor inhibits transformer neutral point DC current, is switched and is executed using the state translation lookaside in parallel with capacitor
It is directly grounded the conversion of operating status and capacity earth operating status.
In the present embodiment, which includes:
When transformer neutral point detects out-of-limit DC current, state translation lookaside is switched and is disconnected, into blocking
Mode；When transformer neutral point DC current disappears, delay closes the switch state translation lookaside, and recovery is directly grounded mould
Formula.
In the present embodiment, the administering method further include:
Overvoltage is executed by high-power thyristor, overcurrent quickly bypasses protection act, and driving condition translation lookaside
It closes the switch and executes the movement of neutral point metallic earthing.
High-power transformer D.C. magnetic biasing problem provided in this embodiment assessment and administering method, based on the detection at scene, after
To assess DC line and converter station, nearby high-power transformer whether there is D.C. magnetic biasing to continuous simulation calculation, and pass through series electrical
Appearance administers the transformer that there are problems that D.C. magnetic biasing, and modification protection and safety are not needed after simple and practical, significant effect, installation certainly
Dynamic device definite value.
Invention is further described in detail below.
In order to which accurate evaluation D.C. magnetic biasing is influenced caused by the transformer station high-voltage side bus of earthing pole periphery.Firstly the need of for scene
Actual operating mode formulates the testing scheme that direct current monopole-ground return circuit method of operation influences AC network main transformer in area.It connects
Need the AC network electricity transformer assessed to carry out live detection work on direct current grounding pole periphery, during record test
Transformer neutral point DC current, transformer noise, transformer vibration etc..Especially emphasis records, DC engineering monopolar operation side
Under formula, when different earth currents, transformer central point current amplitude and its variation tendency.In-situ test principle is as indicated with 2:
It is provided according to " shape high voltage DC earthing pole fire protection technology ", the permission DC current of the every phase winding of transformer are as follows: single-phase
Transformer is the 0.3% of rated current, and three-phase and five-pole transformer is the 0.5% of rated current, and three-phase full-bridge converter is specified
The 0.7% of electric current.Measured result and its development trend are subjected to further simulation calculation, it, must if substantially exceeding directive/guide range
Certain control measures must be taken.
The present embodiment is administered D.C. magnetic biasing problem using series-capacitor, and the rigid hair is more practical, principle is simple,
Modification protection and automatic safety device definite value are not needed after significant effect, installation.Concrete principle is as shown in Figure 3:
Blocking device, which is used, inhibits transformer neutral point DC current in the method for transformer neutral point access capacitor, utilizes
The state translation lookaside disconnecting link (switch) in parallel with capacitor, which is realized, is directly grounded operating status and capacity earth operating status
Conversion.When transformer neutral point detects out-of-limit DC current, state translation lookaside disconnecting link is disconnected, into blocking mould
Formula；When transformer neutral point DC current disappears, state translation lookaside disconnecting link is closed by delay, and recovery is directly grounded mode.
Under capacity earth operating status, when three-phase imbalance failure occurs for AC system, it would be possible to be generated at capacitor both ends
High voltage.Device realizes that overvoltage/current quick by-pass protection device acts by high-power thyristor, and driving condition is converted
It closes the switch and realizes neutral point metallic earthing.
It facts have proved that series-capacitor can effectively inhibit DC current, flow through the DC current of main transformer neutral point
It is down in allowed band, it is ensured that the safe operation of transformer.
During the debugging of certain DC engineering, in order to grasp D.C. magnetic biasing comprehensively caused by the transformer station high-voltage side bus of earthing pole periphery
It influences.Monopole high-power test is carried out to the main electric power transformer of direct current grounding pole periphery 220kV and above.It will
When test result conversion is to DC engineering rated current 5000A monopolar operation, the results showed that the transformer of 3 substations will be had
Neutral point direct current is greater than 200A, and substation of the DC current greater than 100A also has 5, and DC current is greater than 10A's
Substation will have 37.This DC engineering direct current resolution is formulated according to test result, to the change near this DC engineering
Power station installs series-capacitor DC magnetic biasing suppression device additional.Blocking device use transformer neutral point access capacitance for
The method of 66000uF (six parallel connections) capacitor inhibits transformer neutral point DC current, when transformer neutral point detects more
When the DC current of limit is greater than 10A, state translation lookaside disconnecting link is disconnected, into blocking mode；When transformer neutral point direct current
When current vanishes, state translation lookaside disconnecting link is closed by delay, and recovery is directly grounded mode.Under capacity earth operating status,
When three-phase imbalance failure occurs for AC system, it would be possible to generate high voltage at capacitor both ends.When voltage is greater than 800V
When, device realizes that overvoltage/current quick by-pass protection device acts by high-power thyristor, and driving condition change-over switch
Closure realizes neutral point metallic earthing.Portable protective gaps are adjusted to 1 millimeter simultaneously, breakdown (capacitor breakdown when voltage is greater than 2500v
Voltage is 4000v), capacitor and system safety can be effectively protected.
After administering, all 500kV and 220kV substation neutral point direct current are respectively less than 15A inside and outside observation area,
110kV substation neutral point direct current is respectively less than 10A, and D.C. magnetic biasing inhibitory effect is significant.And again to this DC engineering into
The monopolar operation that electric current of having gone is 1~5kA is tested.During test, all substation's oil chromatographies, iron core grounding current etc. are online
Significant change does not occur for monitoring data, and the relay protection of transformer is also without unusual fluctuation.This is also absolutely proved, passes through three phases
It administers, the D.C. magnetic biasing problem of this direct current system engineering has obtained effective control；For high current, big region D.C. magnetic biasing
Improvement is effective.
The high-power transformer that can not clearly whether there is D.C. magnetic biasing problem can accurately be commented through the invention
Estimate, and provides solution in the case where being preferably minimized on the influence of existing protective relaying device to transformer of problems.
The mechanism that scheme is generated from D.C. magnetic biasing administers the theoretical knowledge for inhibiting D.C. magnetic biasing and DC engineering D.C. magnetic biasing
Example combines.Having formulated for engineering has relatively strong targetedly resolution, there is important practical application value.This improvement side
Case has centainly perspective and innovative, is applied to earthing pole peripheral region substation on a large scale for the first time, and achieve very
Good engineer application effect, also has certain reference meaning to other similar engineering.
The above is only a preferred embodiment of the present invention, it is not intended to restrict the invention, it is noted that for this skill
For the those of ordinary skill in art field, without departing from the technical principles of the invention, can also make it is several improvement and
Modification, these improvements and modifications also should be regarded as protection scope of the present invention.
Claims (6)
1. a kind of high-power transformer D.C. magnetic biasing problem appraisal procedure characterized by comprising
Step 1, based on live actual operating mode, the AC network electricity transformer to be assessed to direct current grounding pole periphery is carried out
Live detection obtains under measured result data and DC engineering monopole operating mode, when different earth currents, in transformer
Heart point current amplitude and its variation tendency；The measured result data include test during transformer neutral point DC current,
It is multiple in transformer noise, transformer vibration data；
Step 2, simulation calculation, judgement are carried out based on the measured result data and transformer central point current amplitude variation tendency
Whether simulation result exceeds prescribed limit, if so, determining that transformer has D.C. magnetic biasing.
2. high-power transformer D.C. magnetic biasing problem appraisal procedure according to claim 1, which is characterized in that the step 1
Include:
Based on live actual operating mode, direct current monopole-ground return circuit method of operation is formulated to AC network main transformer in assessment area
The testing scheme of influence.
3. high-power transformer D.C. magnetic biasing problem appraisal procedure according to claim 1, which is characterized in that institute in step 2
Stating prescribed limit includes:
The permission DC current of the every phase winding of transformer are as follows: single-phase transformer is the 0.3% of rated current, three-phase and five-pole transformer
It is the 0.5% of rated current, three-phase full-bridge converter is the 0.7% of rated current.
4. a kind of high-power transformer D.C. magnetic biasing problem administering method, which is characterized in that access electricity using in transformer neutral point
The method of appearance inhibits transformer neutral point DC current, is executed and is directly grounded using the state translation lookaside switch in parallel with capacitor
The conversion of operating status and capacity earth operating status.
5. high-power transformer D.C. magnetic biasing problem administering method according to claim 4, which is characterized in that the improvement side
Method includes:
When transformer neutral point detects out-of-limit DC current, state translation lookaside is switched and is disconnected, into blocking mode；
When transformer neutral point DC current disappears, delay closes the switch state translation lookaside, and recovery is directly grounded mode.
6. high-power transformer D.C. magnetic biasing problem administering method according to claim 5, which is characterized in that further include:
Protection act is quickly bypassed by high-power thyristor execution overvoltage, overcurrent, and driving condition translation lookaside switchs
Closure executes the movement of neutral point metallic earthing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811538705.3A CN109829187A (en) | 2018-12-14 | 2018-12-14 | A kind of assessment of high-power transformer D.C. magnetic biasing problem and administering method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811538705.3A CN109829187A (en) | 2018-12-14 | 2018-12-14 | A kind of assessment of high-power transformer D.C. magnetic biasing problem and administering method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN109829187A true CN109829187A (en) | 2019-05-31 |
Family
ID=66858903
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811538705.3A Pending CN109829187A (en) | 2018-12-14 | 2018-12-14 | A kind of assessment of high-power transformer D.C. magnetic biasing problem and administering method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109829187A (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111751645A (en) * | 2020-06-22 | 2020-10-09 | 北京国网富达科技发展有限责任公司 | Transformer direct-current magnetic bias monitoring method, device, equipment and system |
| CN113408093A (en) * | 2021-06-29 | 2021-09-17 | 西南交通大学 | Capacitive blocking device configuration optimization method based on genetic algorithm |
| CN113675820A (en) * | 2021-07-16 | 2021-11-19 | 国网浙江省电力有限公司杭州供电公司 | Emergency control method for dealing with direct current magnetic biasing of transformer |
| CN115186721A (en) * | 2022-09-13 | 2022-10-14 | 国网江西省电力有限公司电力科学研究院 | IMF-based dynamic calculation method for DC magnetic bias cumulative effect of transformer |
| CN115189480A (en) * | 2022-09-08 | 2022-10-14 | 国网江西省电力有限公司电力科学研究院 | Transformer self-adaptive direct-current magnetic bias adjusting system and method based on multi-source coordination |
| CN115248357A (en) * | 2022-09-21 | 2022-10-28 | 国网山西省电力公司电力科学研究院 | Method and device for detecting DC magnetic bias tolerance of transformer |
| CN117388780A (en) * | 2023-12-11 | 2024-01-12 | 国网江西省电力有限公司电力科学研究院 | Multi-element model-based transformer wide-area direct-current magnetic bias testing method and device |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103439565A (en) * | 2013-09-04 | 2013-12-11 | 博爱县电业公司 | Calculation method for DC magnetic bias current flowing into transformer of high-voltage DC power transmission system |
| CN103514320A (en) * | 2013-07-25 | 2014-01-15 | 国家电网公司 | Method for simulating direct current magnetic biasing of transformer in multi-direct-current-drop-point region |
| CN106291164A (en) * | 2016-07-22 | 2017-01-04 | 国家电网公司 | Noise measuring is utilized to judge the method and system of transformer DC magnetic bias state |
| CN106324378A (en) * | 2015-07-06 | 2017-01-11 | 国家电网公司 | Judgment method of direct-current magnetic bias in 110kV three-phase five-column autotransformer |
| CN106338659A (en) * | 2015-07-06 | 2017-01-18 | 国家电网公司 | Judgment method for direct current magnetic bias in 500kV single-phase autotransformer |
| CN106338661A (en) * | 2015-07-06 | 2017-01-18 | 国家电网公司 | Judgment method for direct current magnetic bias in 110kV three-phase three-column autotransformer |
-
2018
- 2018-12-14 CN CN201811538705.3A patent/CN109829187A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103514320A (en) * | 2013-07-25 | 2014-01-15 | 国家电网公司 | Method for simulating direct current magnetic biasing of transformer in multi-direct-current-drop-point region |
| CN103439565A (en) * | 2013-09-04 | 2013-12-11 | 博爱县电业公司 | Calculation method for DC magnetic bias current flowing into transformer of high-voltage DC power transmission system |
| CN106324378A (en) * | 2015-07-06 | 2017-01-11 | 国家电网公司 | Judgment method of direct-current magnetic bias in 110kV three-phase five-column autotransformer |
| CN106338659A (en) * | 2015-07-06 | 2017-01-18 | 国家电网公司 | Judgment method for direct current magnetic bias in 500kV single-phase autotransformer |
| CN106338661A (en) * | 2015-07-06 | 2017-01-18 | 国家电网公司 | Judgment method for direct current magnetic bias in 110kV three-phase three-column autotransformer |
| CN106291164A (en) * | 2016-07-22 | 2017-01-04 | 国家电网公司 | Noise measuring is utilized to judge the method and system of transformer DC magnetic bias state |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111751645A (en) * | 2020-06-22 | 2020-10-09 | 北京国网富达科技发展有限责任公司 | Transformer direct-current magnetic bias monitoring method, device, equipment and system |
| CN111751645B (en) * | 2020-06-22 | 2023-05-12 | 北京国网富达科技发展有限责任公司 | Method, device, equipment and system for monitoring DC magnetic bias of transformer |
| CN113408093A (en) * | 2021-06-29 | 2021-09-17 | 西南交通大学 | Capacitive blocking device configuration optimization method based on genetic algorithm |
| CN113675820A (en) * | 2021-07-16 | 2021-11-19 | 国网浙江省电力有限公司杭州供电公司 | Emergency control method for dealing with direct current magnetic biasing of transformer |
| CN113675820B (en) * | 2021-07-16 | 2024-02-13 | 国网浙江省电力有限公司杭州供电公司 | Emergency control method for coping with DC magnetic bias of transformer |
| CN115189480A (en) * | 2022-09-08 | 2022-10-14 | 国网江西省电力有限公司电力科学研究院 | Transformer self-adaptive direct-current magnetic bias adjusting system and method based on multi-source coordination |
| CN115189480B (en) * | 2022-09-08 | 2022-12-09 | 国网江西省电力有限公司电力科学研究院 | Transformer self-adaptive direct-current magnetic bias adjusting system and method based on multi-source coordination |
| CN115186721A (en) * | 2022-09-13 | 2022-10-14 | 国网江西省电力有限公司电力科学研究院 | IMF-based dynamic calculation method for DC magnetic bias cumulative effect of transformer |
| CN115248357A (en) * | 2022-09-21 | 2022-10-28 | 国网山西省电力公司电力科学研究院 | Method and device for detecting DC magnetic bias tolerance of transformer |
| CN117388780A (en) * | 2023-12-11 | 2024-01-12 | 国网江西省电力有限公司电力科学研究院 | Multi-element model-based transformer wide-area direct-current magnetic bias testing method and device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109829187A (en) | A kind of assessment of high-power transformer D.C. magnetic biasing problem and administering method | |
| Hasibar et al. | The application of high-speed grounding switches for single-pole reclosing on 500 kV power systems | |
| Nashawati et al. | Impacts of shunt reactors on transmission line protection | |
| CA2567519A1 (en) | Method and equipment for the protection of power systems against geomagnetically induced currents | |
| Kalyuzhny | Analysis of temporary overvoltages during open-phase faults in distribution networks with resonant grounding | |
| Burgess et al. | Minimising the risk of cross-country faults in systems using arc suppression coils | |
| CN107565539B (en) | A kind of AC/DC mixed power system and DC side fault protecting method | |
| Marvasti et al. | A novel method of combined DC and harmonic overcurrent protection for rectifier converters of monopolar HVDC systems | |
| CN110460034B (en) | Direct-current power distribution and utilization system and test method thereof | |
| Das et al. | A novel hybrid differential algorithm for turn to turn fault detection in shunt reactors | |
| CN201666902U (en) | High-voltage line parameter testing and protecting device | |
| CN106684844B (en) | A kind of power distribution network isolated island recognition methods | |
| Borghetti et al. | Transient recovery voltages in vacuum circuit breakers generated by the interruption of inrush currents of large motors | |
| CN112968423B (en) | Overcurrent protection method for protecting turn-to-turn short circuit fault of low-voltage winding of grounding transformer | |
| Atmuri et al. | Neutral reactors on shunt compensated EHV lines | |
| CN100424956C (en) | Fault tolerant re-judging negative sequence direction locking type longitudinal zero voltage inter-turn protection for generator | |
| CN105703349A (en) | Low excitation impedance transformer single-phase grounding protection device and protection method | |
| CN108400005B (en) | Transformer direct-current magnetic bias suppression system and suppression method | |
| Mohanty et al. | Current restrained undervoltage protection scheme of converter dominated microgrids | |
| Ruffing et al. | Resonance phenomena and dc fault handling during intersystem faults in hybrid ac/dc transmission systems with partial dc cabling | |
| Prommetta et al. | AC-protection in the context of AC/DC-hybrid lines | |
| Khan et al. | Analysis of faults and protection schemes for magnetically controlled shunt reactor | |
| CN100492795C (en) | Method for judgement of converter transformer grounding on valve side | |
| Shobole et al. | Protection Coordination Practices for Industrial Ring Distribution Network Case Study of Organized Industrial Zone (GEBZE, Turkey) | |
| CN202424146U (en) | Ferroresonance-resistant control circuit of voltage transformer |
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 |