CN104714158B - AC extra high voltage main transformer modulation combines partial discharge test system and method - Google Patents
AC extra high voltage main transformer modulation combines partial discharge test system and method Download PDFInfo
- Publication number
- CN104714158B CN104714158B CN201510106402.4A CN201510106402A CN104714158B CN 104714158 B CN104714158 B CN 104714158B CN 201510106402 A CN201510106402 A CN 201510106402A CN 104714158 B CN104714158 B CN 104714158B
- Authority
- CN
- China
- Prior art keywords
- transformer
- partial discharge
- high voltage
- pressure side
- extra high
- 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.)
- Active
Links
- 238000012360 testing method Methods 0.000 title claims abstract description 80
- 238000000034 method Methods 0.000 title description 7
- 230000001105 regulatory effect Effects 0.000 claims abstract description 49
- 238000002474 experimental method Methods 0.000 claims abstract description 9
- 238000010998 test method Methods 0.000 claims abstract description 9
- 238000005259 measurement Methods 0.000 claims description 20
- 230000005540 biological transmission Effects 0.000 claims description 6
- 230000000694 effects Effects 0.000 claims description 6
- 238000003825 pressing Methods 0.000 claims description 4
- 230000005284 excitation Effects 0.000 claims description 3
- 230000009466 transformation Effects 0.000 claims 1
- 238000009413 insulation Methods 0.000 description 9
- 230000005611 electricity Effects 0.000 description 5
- 238000001514 detection method Methods 0.000 description 3
- 230000008901 benefit Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000002964 excitative effect Effects 0.000 description 2
- 238000009666 routine test Methods 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000004870 electrical engineering Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Landscapes
- Testing Relating To Insulation (AREA)
Abstract
The present invention provides a kind of AC extra high voltage main transformer modulation joint partial discharge test system, including variable-frequency power sources, testing transformer, compensation reactor, capacitive divider, partial discharge detecting system, and regulating compensation transformer and AC extra high voltage main body transformer, the output end of variable-frequency power sources and the low-pressure side of testing transformer connect, the high-pressure side of testing transformer is connected with the low-pressure side of regulating compensation transformer, the high-pressure side of regulating compensation transformer is connected with the low-pressure side of AC extra high voltage main body transformer, shunt compensation reactor and capacitive divider between testing transformer and regulating compensation transformer, partial discharge detecting system is respectively arranged with AC extra high voltage main body transformer and regulating compensation transformer.AC extra high voltage main transformer and modulation Partial Discharge Testing on Site of the present invention can be completed once, greatly simplify test procedure；AC extra high voltage main transformer does not have to remove with the electrical cable that regulating compensation becomes during experiment, reduces work on the spot amount, improves operating efficiency.
Description
Technical field
The present invention relates to Power Transformer in Field test method, specifically a kind of AC extra high voltage main transformer modulation joint is local
Discharge test system and method.
Background technology
1000kV AC extra high voltage power transmission engineerings are current voltage class highest ac transmission engineerings in the world, with Shanxi
The southeast-Nanyang-Jingmen UHVAC demonstration project and extension project, Wan electricity Dong send Huainan-Shanghai AC extra high voltage defeated
Electrical engineering puts into operation in succession, and rapid growth momentum is presented in China in AC extra high voltage.
AC extra high voltage transformer is one of equipment of the most important most expensive of AC extra high voltage power transmission engineering.In order to ensure to become
Depressor production, installation quality, the hidden danger of Transformer is searched, it is necessary to carry out transformer handing-over and prerun experiment at the scene.
For AC extra high voltage transformer, and induced over voltage withstand test during long with measurement of partial discharge (ACLD, it is often referred to simply as local
Discharge test) it is that difficulty is maximum, examination is most strict, to the reflection of inside transformer insulation defect, most sensitively handing-over prerun tests it
One.
Extra-high voltage transformer is because voltage class is high, size is big, for the ease of transport, by the body of extra-high voltage transformer and
Regulating compensation part branch mailbox arrangement, as main body transformer and regulating compensation transformer.
At present, the general AC extra high voltage partial discharge of transformer measuring method in China is respectively to main body transformer and tune
Compensator transformer is pressed to carry out measurement of partial discharge, this measuring method is primarily present following problem：
1) the transformer insulated examination of regulating compensation is inadequate.
2) need to remove, reduce the connecting line of main transformer modulation, workload is big.
3) local discharge test twice is carried out, it is necessary to which testing equipment is more, efficiency is low.
In consideration of it, set about have developed AC extra high voltage main transformer modulation joint partial discharge test method and experimental rig.
The content of the invention
The invention aims to overcome blank existing for prior art and deficiency, there is provided a kind of AC extra high voltage main transformer
Modulation combines partial discharge test system and method, greatly simplifies test procedure, reduces work on the spot amount, improves work effect
Rate.
The present invention adopts the following technical scheme that：
A kind of AC extra high voltage main transformer modulation combines partial discharge test system, including variable-frequency power sources, testing transformer, benefit
Repay reactor, capacitive divider, partial discharge detecting system and subjects regulating compensation transformer and AC extra high voltage master
Body transformer, the output end of variable-frequency power sources and the low-pressure side of testing transformer are connected, and high-pressure side and the pressure regulation of testing transformer are mended
The low-pressure side connection of transformer is repaid, the high-pressure side of regulating compensation transformer connects with the low-pressure side of AC extra high voltage main body transformer
Connect, compensation reactor for compensating perceptual capacity is parallel between testing transformer and regulating compensation transformer and for surveying
The capacitive divider of amount, Partial Discharge Detection system is respectively arranged with AC extra high voltage main body transformer and regulating compensation transformer
System.
A kind of AC extra high voltage main transformer modulation combines partial discharge test method, completes to exchange by above-mentioned pilot system
Extra-high voltage main transformer modulation scene joint partial discharge test, is concretely comprised the following steps：
Step 1: connection variable-frequency power sources, testing transformer, compensation reactor, capacitive divider, Partial Discharge Detection system
System, and subjects AC extra high voltage main body transformer and regulating compensation transformer, form AC extra high voltage main transformer modulation and show
Field joint partial discharge test loop；
Step 2: in AC extra high voltage main body high voltage side of transformer, medium voltage side, low-pressure side and regulating compensation transformer high-voltage
The partial discharge measurement end of side 4 carries out pulse matching, and records mutual partial discharge transmission and compare relation；
Step 3: combining to AC extra high voltage main transformer modulation scene, partial discharge test loop is pressurizeed and partial discharge is surveyed
Amount, wherein regulating compensation transformer is both used as subjects, serves as the effect of testing transformer, AC extra high voltage main transformer again
Reach local discharge test voltage simultaneously with regulating compensation transformer, partial discharge detecting system completes AC extra high voltage main transformer pressure simultaneously
The measurement of partial discharge of device and regulating compensation transformer；
Step 4: such as partial discharge measurement result exception, analyzed and judged according to shelf depreciation positioning mode.
Technical scheme has following beneficial effect：
1st, AC extra high voltage main transformer modulation joint Partial Discharge Testing on Site is at home and abroad realized first, suitable for the country
All AC extra high voltage transformer field partial discharge tests；
2nd, AC extra high voltage main transformer and regulating compensation become Partial Discharge Testing on Site and once completed, and make test procedure greatly simple
Change, improve operating efficiency；
3rd, during the independent local discharge test of AC extra high voltage main transformer, low-pressure side precharge is generally 173.2kV；Body becomes and modulation
Joint local discharge test, because two-stage is boosted, it need to only exchange and become tap-changing windings application voltage 45.6kV (with Jingmen station AC extra high voltage
Exemplified by transformer), therefore testing equipment output voltage drops to 45.6kV from 173.2kV, so that test voltage is more held
Easily, greatly simplify the testing equipments such as variable-frequency power sources, compensation reactor, saved experimentation cost；
4th, in order to which the insulation examination with AC extra high voltage main transformer matches, regulating compensation, which becomes, applies voltage compared with its routine tests
When greatly increase, and increase modulation insulation examination dynamics, make modulation insulation examine more science and comprehensively；
AC extra high voltage main transformer does not have to remove with the electrical cable that regulating compensation becomes when the 5th, testing, and reduces work on the spot
Amount, improves operating efficiency.
Brief description of the drawings
Fig. 1 is the structural principle block diagram of AC extra high voltage main transformer modulation joint partial discharge test system of the present invention；
Fig. 2 is partial discharge test pressurization protocols schematic diagram of the present invention.
Wherein：1-variable-frequency power sources；2-testing transformer；3-compensation reactor；4-capacitive divider；5-part is put
Electricity detecting system；6-regulating compensation transformer；7-AC extra high voltage main body transformer.
Embodiment
Below in conjunction with the accompanying drawing in the present invention, the technical scheme in the present invention is clearly and completely described.
Refer to Fig. 1, AC extra high voltage main transformer modulation joint partial discharge test system of the present invention include variable-frequency power sources 1,
Testing transformer 2, compensation reactor 3, capacitive divider 4, partial discharge detecting system 5 and subjects regulating compensation become
Depressor 6 and AC extra high voltage main body transformer 7, the wherein output end of variable-frequency power sources 1 are connected with the low-pressure side of testing transformer 2,
The high-pressure side of testing transformer 2 is connected with the low-pressure side of regulating compensation transformer 6, the high-pressure side of regulating compensation transformer 6 and friendship
The low-pressure side connection of extra-high voltage main body transformer 7 is flowed, is parallel with and is used between testing transformer 2 and regulating compensation transformer 6
The compensation reactor 3 of perceptual capacity and the capacitive divider 4 for measurement are compensated, in AC extra high voltage main body transformer 7 and is adjusted
Pressure compensator transformer 6 on be respectively arranged with partial discharge detecting system 5, specifically, the high-pressure side of AC extra high voltage main body transformer 7,
Partial discharge detecting system 5 is installed respectively at medium voltage side, low-pressure side and regulating compensation transformer 6 high-pressure side four bottom shielding of bushing.
AC extra high voltage main transformer modulation joint local discharge test supplies the low-pressure side of testing transformer 2, experiment using variable-frequency power sources 1
The high-pressure side of transformer 2 gives modulation (regulating compensation transformer 6) low-pressure side to apply test voltage, the effect of testing transformer 2 be by
Its voltage exported is increased to modulation low-pressure side test voltage 45.6kV.Modulation high-pressure side is that body becomes (AC extra high voltage main body
Transformer 7) low-pressure side voltage supply, reach the excitation voltage of the local discharge test of AC extra high voltage main body transformer 7The measurement voltage of local discharge test reachesIt is determined that variable-frequency power sources 1, experiment become according to above-mentioned voltage
The parameter of the grade testing equipment of depressor 2.
Each parameters of operating part：
1st, variable-frequency power sources 1
Power input：380 (1 ± 10%) V, three-phase, 50Hz；
Output voltage：0~350V, single-phase, continuously adjustabe；
Power output：2×400kW
Operating frequency range：30Hz~300Hz；
Frequency adjusts resolution ratio：0.1Hz；
Output waveform aberration rate：≤ 1.0%；
Output voltage instability：≤ 1.0%；
Partial discharge quantity：≤50pC.
2nd, testing transformer 2
Rated capacity：≥600kVA；
Rated voltage：60/0.4kV or 55/0.35kV；
Rated frequency：100Hz；
The number of phases：It is single-phase；
Polarity：I, I0；
Partial discharge quantity：Under rated voltage, partial discharge quantity≤50pC of HV Terminal.
3rd, compensation reactor 3
Rated voltage：50kV；
Rated current：≥60A；
Rated frequency：100Hz；
Saturated characteristic：In 0%~100% rated voltage, its C-V characteristic is linear；
Partial discharge quantity：Under rated voltage, partial discharge quantity≤50pC.
4th, other parts are function instrument.
The present invention also provides a kind of AC extra high voltage main transformer modulation joint partial discharge test method, and it uses above-mentioned experiment
System combines partial discharge test to complete AC extra high voltage main transformer modulation scene, concretely comprises the following steps：
Step 1: connection variable-frequency power sources 1, testing transformer 2, compensation reactor 3, capacitive divider 4, Partial Discharge Detection
System 5, and subjects AC extra high voltage main body transformer 7 and regulating compensation transformer 6, form AC extra high voltage main transformer and adjust
Become live union office portion discharge test loop；
It is Step 2: high in the high-pressure side of AC extra high voltage main body transformer 7, medium voltage side, low-pressure side and regulating compensation transformer 6
Press the partial discharge measurement end of side 4 to carry out pulse matching, and record mutual partial discharge transmission and compare relation；
Step 3: combining to AC extra high voltage main transformer modulation scene, partial discharge test loop is pressurizeed and partial discharge is surveyed
Amount, pressurization protocols are as shown in Figure 2：
AC extra high voltage main body transformer 7 high-pressure side pre-add (excitatory) voltage U1=952.7kV, regulating compensation transformer 6
During high-pressure side pre-add (excitatory) voltage U1=173.2kV, test frequency >=100Hz, pressing time T=100 × 60/fs；Experiment
Frequency<During 100Hz, T=60s.The high-pressure side partial discharge measurement voltage U2=825.6kV of AC extra high voltage main body transformer 7, pressure regulation are mended
Repay transformer 6 high-pressure side partial discharge measurement voltage U2=150.1kV, pressing time 60min；AC extra high voltage main transformer voltage U3=
698.6kV, regulating compensation transformer voltage U3=127.0kV.
The present invention matches for the insulation examination with AC extra high voltage main transformer, the application voltage of regulating compensation transformer 6
Greatly increased during compared with its routine tests, partial discharge measurement voltage is improved to 150.1kV by 109.1kV, and increases the insulation of modulation
Examination dynamics, make modulation insulation examine more science and comprehensively.
During the independent local discharge test of AC extra high voltage main transformer, low-pressure side precharge is that testing equipment output voltage is generally
173.2kV, the present invention is become using body combines local discharge test with modulation, because two-stage is boosted, need to only exchange and become regulating compensation change
Depressor 6 apply voltage 45.6kV (by taking the AC extra high voltage transformer of Jingmen station as an example), therefore the output voltage of testing transformer 2 from
173.2kV drops to 45.6kV, so that test voltage is more prone to, makes the testing equipments such as variable-frequency power sources, compensation reactor
Greatly simplify, saved experimentation cost.
As shown in Fig. 2 when applying test voltage, switch on power under the voltage no more than U2/3；U3 is risen to, keeps 5
Minute, record electric discharge value；Then raised voltage without exception is kept for 5 minutes, record electric discharge value to U2；It is without exception to rise electricity again
U1 is pressed onto, is kept for the T seconds；Then, voltage is reduced incessantly immediately to U2, is kept 60min, is carried out measurement of partial discharge, herein
Period, record the value that once discharges within every 5 minutes；Voltage is reduced again to U3, is kept for 5 minutes, record electric discharge value；Finally reduce electricity
Cut off the electricity supply when being pressed onto below U2/3, off-test.
Step 4: such as partial discharge measurement result is abnormal, it is more according to " calibration of the end of four-terminal measurement-four " shelf depreciation positioning mode etc.
Kind method is analyzed and judged.
The advantages and positive effects of the present invention：Regulating compensation transformer depressor is both subjects in the present invention, is served as again
The effect of testing transformer；AC extra high voltage main transformer and regulating compensation transformer depressor reach local discharge test voltage simultaneously,
Partial discharge detecting system completes the measurement of partial discharge of AC extra high voltage main transformer and regulating compensation transformer simultaneously, and exchange is extra-high
Pressure main transformer and modulation Partial Discharge Testing on Site are once completed, and are greatly simplified test procedure, are improved operating efficiency；Experiment is set
The standby required voltage that applies substantially reduces, and obtains test voltage and is more prone to, makes the testing equipment such as variable-frequency power sources, compensation reactor pole
It is big to simplify, save experimentation cost；The insulation examination dynamics of modulation is increased, the insulation of modulation is examined more science and complete
Face；AC extra high voltage main transformer does not have to remove with the electrical cable that regulating compensation becomes during experiment, reduces work on the spot amount, carries
High operating efficiency.
The foregoing is only a specific embodiment of the invention, but protection scope of the present invention is not limited thereto, any
Belong to those skilled in the art the invention discloses technical scope in, the change or replacement that can readily occur in, all should
It is included within the scope of the present invention.Therefore, protection scope of the present invention should be defined by scope of the claims.
Claims (1)
1. a kind of AC extra high voltage main transformer modulation combines partial discharge test method, it is characterised in that concretely comprises the following steps：
Step 1: connection variable-frequency power sources (1), testing transformer (2), compensation reactor (3), capacitive divider (4), shelf depreciation
Detecting system (5), and subjects AC extra high voltage main body transformer (7) and regulating compensation transformer (6), it is special to form exchange
High pressure main transformer modulation scene joint partial discharge test loop, the wherein output end of variable-frequency power sources (1) and testing transformer (2)
Low-pressure side is connected, and the high-pressure side of testing transformer (2) is connected with the low-pressure side of regulating compensation transformer (6), regulating compensation transformation
The high-pressure side of device (6) is connected with the low-pressure side of AC extra high voltage main body transformer (7), in testing transformer (2) and regulating compensation
The compensation reactor (3) for compensating perceptual capacity and the capacitive divider (4) for measurement are parallel between transformer (6),
Partial discharge detecting system (5) is respectively arranged with AC extra high voltage main body transformer (7) and regulating compensation transformer (6), is tested
The effect of transformer (2) is that the voltage output it is increased to modulation low-pressure side test voltage 45.6kV；
It is Step 2: high in AC extra high voltage main body transformer (7) high-pressure side, medium voltage side, low-pressure side and regulating compensation transformer (6)
Press the partial discharge measurement end of side 4 to carry out pulse matching, and record mutual partial discharge transmission and compare relation；
Step 3: combining to AC extra high voltage main transformer modulation scene, partial discharge test loop is pressurizeed and partial discharge measures, its
Middle regulating compensation transformer (6) is both used as subjects, serves as the effect of testing transformer, AC extra high voltage main transformer again
(7) and regulating compensation transformer (6) while local discharge test voltage is reached, partial discharge detecting system (5) while to complete exchange special
The measurement of partial discharge of high pressure main transformer (7) and regulating compensation transformer (6)；
Specifically, AC extra high voltage main body transformer (7) high-pressure side pre-add excitation voltage is 952.7kV, regulating compensation transformer
(6) pre-add excitation voltage in high-pressure side is 173.2kV, during test frequency >=100Hz, pressing time T=100 × 60/fs；Experiment frequency
Rate<During 100Hz, T=60s；Partial discharge measurement voltage in AC extra high voltage main body transformer (7) high-pressure side is 825.6kV, regulating compensation
Transformer (6) high-pressure side partial discharge measurement voltage is 150.1kV, pressing time 60min；AC extra high voltage main transformer voltage is
698.6kV, regulating compensation transformer voltage are 127.0kV；
Step 4: such as partial discharge measurement result exception, analyzed and judged according to shelf depreciation positioning mode.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510106402.4A CN104714158B (en) | 2015-03-11 | 2015-03-11 | AC extra high voltage main transformer modulation combines partial discharge test system and method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510106402.4A CN104714158B (en) | 2015-03-11 | 2015-03-11 | AC extra high voltage main transformer modulation combines partial discharge test system and method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104714158A CN104714158A (en) | 2015-06-17 |
| CN104714158B true CN104714158B (en) | 2017-12-15 |
Family
ID=53413651
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510106402.4A Active CN104714158B (en) | 2015-03-11 | 2015-03-11 | AC extra high voltage main transformer modulation combines partial discharge test system and method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104714158B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106199349B (en) * | 2016-06-21 | 2019-02-22 | 国网天津市电力公司 | Partial discharge of transformer region decision method based on calibration square-wave signal transmitting ratio |
| CN110208661A (en) * | 2019-06-21 | 2019-09-06 | 中国电建集团河南工程有限公司 | Offshore boosting station transformer pressure resistance local discharge test method |
| CN110398674A (en) * | 2019-08-30 | 2019-11-01 | 国网山西省电力公司电力科学研究院 | A kind of extra-high voltage parallel reactance is pressure-resistant and local discharge test device |
| CN110568330A (en) * | 2019-09-16 | 2019-12-13 | 国网河北省电力有限公司电力科学研究院 | Three-phase three-winding transformer induction voltage band partial discharge test parameter estimation method |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002323533A (en) * | 2001-04-27 | 2002-11-08 | Sumitomo Electric Ind Ltd | Partial discharge testing method for electric power equipment |
| CN102193051A (en) * | 2010-03-05 | 2011-09-21 | 湖北省电力试验研究院 | Field local discharge testing device and method of 1000 kV alternating current extra-high voltage transformer |
| CN202870240U (en) * | 2012-09-11 | 2013-04-10 | 青海电力科学试验研究院 | A partial discharge testing device of a converter transformer at a high altitude locality |
| CN103207358A (en) * | 2013-04-15 | 2013-07-17 | 广东电网公司佛山供电局 | High-voltage power cable nondestructive detection device |
| CN204405793U (en) * | 2015-03-11 | 2015-06-17 | 国家电网公司 | AC extra high voltage main transformer modulation associating partial discharge test system |
-
2015
- 2015-03-11 CN CN201510106402.4A patent/CN104714158B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002323533A (en) * | 2001-04-27 | 2002-11-08 | Sumitomo Electric Ind Ltd | Partial discharge testing method for electric power equipment |
| CN102193051A (en) * | 2010-03-05 | 2011-09-21 | 湖北省电力试验研究院 | Field local discharge testing device and method of 1000 kV alternating current extra-high voltage transformer |
| CN202870240U (en) * | 2012-09-11 | 2013-04-10 | 青海电力科学试验研究院 | A partial discharge testing device of a converter transformer at a high altitude locality |
| CN103207358A (en) * | 2013-04-15 | 2013-07-17 | 广东电网公司佛山供电局 | High-voltage power cable nondestructive detection device |
| CN204405793U (en) * | 2015-03-11 | 2015-06-17 | 国家电网公司 | AC extra high voltage main transformer modulation associating partial discharge test system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN104714158A (en) | 2015-06-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104714158B (en) | AC extra high voltage main transformer modulation combines partial discharge test system and method | |
| CN109521338B (en) | Frequency conversion parallel resonance voltage withstand test method based on cascade voltage boosting | |
| CN101294985B (en) | Power supply device for controllable reactor induction voltage-resistant experiment and its partial discharging measurement method | |
| CN103884933B (en) | A kind of high-power transformer temperature-raising experimental method | |
| CN201203633Y (en) | Power supply device for controllable inductor induction voltage-resistant experiment | |
| CN105353335A (en) | Automatic verification device for AC potentiometer and automatic verification method | |
| CN107632241A (en) | A kind of apparatus and method for testing paper oil insulation partial discharge characteristic | |
| CN203217005U (en) | Converter transformer no-load test schematic wiring diagram | |
| CN109581168A (en) | A kind of converter power transformer In situ DC partial discharge test system and method | |
| CN102121954A (en) | Test device and test method for high-voltage dielectric loss | |
| CN110456236A (en) | Railway traction transformer shelf depreciation handover property test method | |
| CN109342910A (en) | A kind of complete electric type local discharge detection device and detection method | |
| CN208752168U (en) | A kind of cable voltage pilot system of variable-frequency series-resonance | |
| CN204129166U (en) | One can phase shift alternating-current voltage resistance test device | |
| CN201724964U (en) | Power device for AC and DC superimposed synthetized voltage test of voltage test | |
| CN101403784B (en) | AC frequency conversion resonance vibration pressure-proof device for AC motor stator winding, and method therefor | |
| CN202041606U (en) | Frequency tripling transformer load test device | |
| CN204405793U (en) | AC extra high voltage main transformer modulation associating partial discharge test system | |
| CN111650442B (en) | Test loop structure and test method for measuring loss of shunt reactor | |
| CN101865988A (en) | Test power supply for error check of high-voltage electric energy metering device and implementation method thereof | |
| CN104808022A (en) | Temperature rise test connection method for three-side combined operation of three-phase three-winding transformer | |
| CN205139353U (en) | Automatic calibration equipment of AC potentiometer | |
| CN102193051A (en) | Field local discharge testing device and method of 1000 kV alternating current extra-high voltage transformer | |
| CN206920546U (en) | A kind of wiring construction of low-pressure side two-winding transformer partial discharge test | |
| CN102269786A (en) | Load testing device for triple-frequency transformer |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |