CN102116803A - Method for testing capacitance and dielectric loss value of 220KV coupling capacitor - Google Patents
Method for testing capacitance and dielectric loss value of 220KV coupling capacitor Download PDFInfo
- Publication number
- CN102116803A CN102116803A CN2010106032489A CN201010603248A CN102116803A CN 102116803 A CN102116803 A CN 102116803A CN 2010106032489 A CN2010106032489 A CN 2010106032489A CN 201010603248 A CN201010603248 A CN 201010603248A CN 102116803 A CN102116803 A CN 102116803A
- Authority
- CN
- China
- Prior art keywords
- dielectric loss
- capacitor
- heart yearn
- coupling condenser
- tester
- 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
Images
Landscapes
- Measurement Of Resistance Or Impedance (AREA)
Abstract
The invention relates to a method for testing capacitance and a dielectric loss value of a 220KV coupling capacitor. The method comprises the following steps of: grounding a 220kV circuit which is connected with equipment body through a grounding knife; connecting a core wire of a high voltage line to a second lap point of a tested coupling capacitor; connecting a core wire of a CX end of an instrument to a third lap point of the tested coupling capacitor; introducing a signal of a vector value I of total current which flows through an upper section of the capacitor and a lower section of the capacitor into a high voltage end of a dielectric loss tester by the core wire of the high voltage line; and measuring a vector value IC2 of current which flows through the lower section of the capacitor by the measuring end CX of the dielectric loss tester, considering the vector IC1 of the current which flows through the upper section of the capacitor as vector difference between I and IC2, comparing amplitude and phase of the current with the amplitude and the phase of the current which flows through a standard capacitor and keeping the amplitude and the phase of voltage in test unchanged to measure the capacitances of the upper section of the capacitor and the lower section of the capacitor and dielectric loss. By the method, the capacitances of the upper section of the capacitor and the lower section of the capacitor and the dielectric loss value are simultaneously measured without disassembling a high-pressure lead or replacing a measuring lead.
Description
Technical field
The present invention relates to the method for the routine maintenance of 220KV high voltage substation, is the method for testing of a kind of 220KV coupling condenser electric capacity and dielectric loss value specifically.
Background technology
The 220KV coupling condenser electric capacity in tradition 220KV and the above electric pressure transformer station and the method for testing of dielectric loss value are to remove high-voltage connection, change the test of measuring lead wire.Traditional measuring principle is as follows:
At present, when classic method is measured 220KV coupling condenser electric capacity and dielectric loss value, all adopt positive mode of connection to carry out for upper and lower two joints, principle as shown in Figure 1, 2,
Must take first overlapped points 1 and the 3rd overlapped points 3 earlier apart before the test, the high-voltage connection and first overlapped points 1 are disconnected, utilize the dielectric loss tester to measure saving up and down respectively then.At this moment, the condenser capacity of economize on electricity up and down of coupling condenser measured all adopt positive mode of connection, the dielectric loss tester is C at the capacitance value that first overlapped points 1 and second overlapped points, 2 intermittent gaugings measure joint
1With dielectric loss angle tangent be tan δ
1, the dielectric loss tester measures down at second overlapped points 2 and the 3rd overlapped points 3 intermittent gaugings that the capacitance value of joint is C
2With dielectric loss angle tangent be tan δ
2As seen the coupling condenser traditional measurement method should be removed high-voltage connection and change the measurement wiring again, not only under maintainer's condition of limited, the preventive trial time is longer, is unfavorable for quick maintenance, and removing high-voltage connection simultaneously also is a kind of potential potential safety hazard to the maintainer.Described positive mode of connection is measured (positive connection is measured) and is meant by martingale shown in Figure 4, and the dielectric loss tester is by instrument high-pressure side heart yearn and instrument CX end heart yearn measurement data.
The shortcoming of its existence is:
1, because the 220KV coupling condenser all is distributed in the edge of transformer station usually, lift truck can't enter;
2, coupling condenser high-voltage connection height, thick, long, heavy, induced voltage is very high when having a power failure at non-full station, so under, personnel's condition of limited short at power off time, remove that high-voltage connection tests is to be difficult to realize;
3, to repeatedly change the measurement wiring in the test process, promptly prolong the repair time easily to make test result inaccurate again; Add the introducing of electric field and spatial interference, dispersiveness increase, the accuracy of test figure are descended, accurately the insulation status of judgment device.
Summary of the invention
At the defective that exists in the prior art, the object of the present invention is to provide the method for testing of a kind of 220KV coupling condenser electric capacity and dielectric loss value, do not tear high-voltage connection open and measure; Not changing measuring lead wire measures; Measure two economize on electricity capacity of condenser and dielectric loss values up and down simultaneously.
For reaching above purpose, the technical scheme that the present invention takes is:
The method of testing of a kind of 220KV coupling condenser electric capacity and dielectric loss value is characterized in that, may further comprise the steps:
The 220kV link tester that will be connected with apparatus body is crossed ground connection plug-in strip ground connection, makes equipment be in inspecting state,
The hi-line heart yearn is connected to second overlapped points 2 of tested coupling condenser,
Instrument CX end heart yearn is connected to the 3rd overlapped points 3 of tested coupling condenser,
The hi-line heart yearn will flow through " high pressure " end of the total current vector value I signal introducing dielectric loss tester of the container that economizes on electricity up and down, the measuring junction " C of dielectric loss tester
X" measure and flow through the current vector value I of economize on electricity container down
C2, then flow through the economize on electricity container current vector I
C1Be I and I
C2Vectorial difference,
Again by with the comparison of the amplitude and the phase place of the electric current that flows through standard capacitor, and the amplitude and the phase invariant of voltage in the test promptly measured economize on electricity up and down container amount and dielectric loss.
On the basis of technique scheme, described instrument CX end heart yearn is the heart yearn of a client cables, and instrument CX end heart yearn is communicated with the C of dielectric loss tester
XTerminal and the 3rd overlapped points 3 measure signal.
On the basis of technique scheme, described client cables is a high-tension cable, and double shield structure can bear the outer ground connection of 15kV at least between the two-layer shielding, and internal layer has high pressure, can mop floor during measurement.
The method of testing of 220KV coupling condenser electric capacity of the present invention and dielectric loss value, benefit and advantage are as follows:
(1) dielectric loss of economize on electricity appearance up and down and electric capacity test are once finished;
(2) electric field and spatial interference are dropped to minimum, improved accuracy of measurement;
(3) the original conventional method of time ratio of finishing measurement has reduced (with a calculating mutually) more than 2/3;
(4) saved the use amount (originally disconnecting lead needs 3 maintainers and 1 lift truck at least, improves the back and only needs 3 maintainers, does not need lift truck) of human and material resources.
(5) effectively stopped the danger of ascending a height, induced electricity injury and the mechanical wounding that the test of coupling condenser dielectric loss brings, it is dangerous and to the risk of tester's life potential injury further to have reduced high-potting self.
Description of drawings
The present invention has following accompanying drawing:
Joint test wiring on Fig. 1 coupling condenser,
Fig. 2 coupling condenser is joint test wiring down,
Fig. 3 coupling condenser not disconnection test wiring (lv shielded method measurement),
The positive connection of Fig. 4 is measured wiring schematic diagram,
Fig. 5 opposition method is measured wiring schematic diagram,
Fig. 6 lv shielded method is measured wiring schematic diagram,
Fig. 7 alien frequencies power principle block diagram,
Fig. 8 light pulse modulation high pressure buffer circuit block diagram,
Fig. 9 Fourier transform Spectral Analysis Method measuring system block diagram.
Embodiment
Below in conjunction with accompanying drawing the present invention is described in further detail.
When carrying out 220KV and above coupling condenser dielectric loss, electric capacity test at the scene, because high-voltage connection is connected with apparatus body by first overlapped points 1, so when equipment is in inspecting state, need by ground connection plug-in strip ground connection.The 3rd overlapped points 3 is easily taken apart.In the prior art, opposition method is measured wiring as shown in Figure 5, and the dielectric loss tester is by instrument high-pressure side heart yearn measurement data, and tested coupling condenser one end is connected with instrument high-pressure side heart yearn, and the other end need pass through ground connection plug-in strip ground connection.
Comprehensive above-mentioned situation, the present invention adopts lv shielded method to measure, and shown in Fig. 3,6, the method for testing of 220KV coupling condenser electric capacity of the present invention and dielectric loss value may further comprise the steps:
The 220kV link tester that will be connected with apparatus body is crossed ground connection plug-in strip ground connection, makes equipment be in inspecting state,
Hi-line heart yearn (instrument high-pressure side heart yearn) is connected to second overlapped points 2 of tested coupling condenser, and described second overlapped points 2 is the high pressure end points,
Hold heart yearn to be connected to the 3rd overlapped points 3 of tested coupling condenser instrument CX, described instrument CX end heart yearn is the heart yearn of a client cables, and instrument CX end heart yearn is communicated with the C of dielectric loss tester
XTerminal and the 3rd overlapped points 3 measure signal,
The hi-line heart yearn will flow through " high pressure " end of the total current vector value I signal introducing dielectric loss tester of the container that economizes on electricity up and down, the measuring junction " C of dielectric loss tester
X" measure and flow through the current vector value I of economize on electricity container down
C2, then flow through the economize on electricity container current vector I
C1Be I and I
C2Vectorial difference,
Again by with the comparison of the amplitude and the phase place of the electric current that flows through standard capacitor, and (voltage refers to the voltage of dielectric loss tester " high pressure " end output for the amplitude of voltage and phase invariant in the test, promptly be added in the voltage of second overlapped points 2 of tested coupling condenser), promptly measure economize on electricity up and down container amount and dielectric loss, realize not tearing high-voltage connection open, do not change measuring lead wire and measure.The dielectric loss tester is finished " measuring economize on electricity up and down container amount and dielectric loss " work automatically.
On the basis of technique scheme, described client cables is a high-tension cable, and double shield structure can bear the outer ground connection of 15kV at least between the two-layer shielding, and internal layer has high pressure, can mop floor during measurement.
The test gordian technique
Disturb interference and coupling condenser dielectric loss down and electric capacity accurately to measure in order to realize on-the-spot powerful power frequency, and last economize on electricity condenser capacity is basic identical in positive opposition method measurement result, adopt automated media loss test instrument AI-6000F used herein converter technique and Fourier transform digital filtering technique realize that highfield disturbs and the dielectric loss measurement under the disconnecting lead not, and its cardinal principle is made up of three parts: alien frequencies power technology, high-pressure side sample of signal isolation technology, signal transformation treatment technology.
1 alien frequencies power technology
Realize the alien frequencies power supply by ac-dc-ac inverter circuit and H.V. step up transformer, as shown in Figure 7.This part comprises AC-DC-AC power transforming main circuit, IGBT driving circuit and voltage sampling and regulating circuit.The AC-DC-AC power transforming main circuit adopts popular IGBT power switch and SPWM control technology to obtain the sine wave of low distortion; The IGBT driving circuit converts the SPWM pulse signal of single-chip computer control system output to the drive pulse signal of IGBT requirement on devices; Voltage sample circuit feeds back to single-chip computer control system with the output voltage of variable-frequency power sources, forms a dynamic feedback regulation voltage through regulating circuit again, to realize closed loop voltage stabilizing control; Variable-frequency power sources also needs its output frequency is fed back to Single Chip Microcomputer (SCM) system, realizes synchronized sampling.
2 high-pressure side sample of signal isolation technologies
For the sampling that realizes high-pressure side electric current and voltage signal low distortion is isolated, particularly during opposition method, the accurate measurement of dielectric loss under the high common mode disturbance voltage and electric capacity, this paper adopts light pulse modulation high pressure isolation method, as shown in Figure 8.The curtage sampled signal of sample circuit output is respectively iv or uv, and the signal after the isolate demodulation is respectively iv ' or uv '.The V-F FM circuit is converted to the frequency modulation on pulse signal at high-pressure side with sampled analog signals; And, receive this light pulse signal at low pressure end " light/electric pulse receives " circuit by the pulse of " electricity/light pulse emission " circuit transmission infrared ray, make it to be converted to electric impulse signal; " PLL demodulation of phase locking " circuit reduction sampled analog signals at last.So just realized the electricity isolation of high-pressure side to low pressure end.Current channel is adopted identical circuit structure and identical circuit parameter with voltage channel, and the signal iv that obtains at low pressure end after then isolating has identical delay with uv with respect to iv ' and uv ', and its relative phase relation is constant.
3 signal transformation treatment technologies
Carry out Fourier transform from voltage, current data that the test product up-sampling obtains, thereby obtain the phase place and the amplitude of voltage, current first harmonics, and then try to achieve the dielectric loss and the electric capacity of test product by complex admittance definition, concrete derivation is seen document (Li Shunyao " capacitance error analysis and calculating when 220kV CVT does not take out stitches test " [J] High-Voltage Electrical Appliances, 2006,42 (6): 468-469).This method measuring system as shown in Figure 9.
Claims (3)
1. the method for testing of 220KV coupling condenser electric capacity and dielectric loss value is characterized in that, may further comprise the steps:
The 220kV link tester that will be connected with apparatus body is crossed ground connection plug-in strip ground connection, makes equipment be in inspecting state,
The hi-line heart yearn is connected to second overlapped points (2) of tested coupling condenser,
Instrument CX end heart yearn is connected to the 3rd overlapped points (3) of tested coupling condenser,
The hi-line heart yearn will flow through " high pressure " end of the total current vector value I signal introducing dielectric loss tester of the container that economizes on electricity up and down, the measuring junction " C of dielectric loss tester
X" measure and flow through the current vector value I of economize on electricity container down
C2, then flow through the economize on electricity container current vector I
C1Be I and I
C2Vectorial difference,
Again by with the comparison of the amplitude and the phase place of the electric current that flows through standard capacitor, and the amplitude and the phase invariant of voltage in the test promptly measured economize on electricity up and down container amount and dielectric loss.
2. the method for testing of 220KV coupling condenser electric capacity as claimed in claim 1 and dielectric loss value is characterized in that: described instrument CX end heart yearn is the heart yearn of a client cables, and instrument CX end heart yearn is communicated with the C of dielectric loss tester
XTerminal and the 3rd overlapped points (3) measure signal.
3. the method for testing of 220KV coupling condenser electric capacity as claimed in claim 2 and dielectric loss value, it is characterized in that: described client cables is a high-tension cable, and double shield structure can bear the outer ground connection of 15kV at least between the two-layer shielding, internal layer has high pressure, can mop floor during measurement.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010106032489A CN102116803A (en) | 2010-12-24 | 2010-12-24 | Method for testing capacitance and dielectric loss value of 220KV coupling capacitor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010106032489A CN102116803A (en) | 2010-12-24 | 2010-12-24 | Method for testing capacitance and dielectric loss value of 220KV coupling capacitor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102116803A true CN102116803A (en) | 2011-07-06 |
Family
ID=44215664
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2010106032489A Pending CN102116803A (en) | 2010-12-24 | 2010-12-24 | Method for testing capacitance and dielectric loss value of 220KV coupling capacitor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102116803A (en) |
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102662110A (en) * | 2012-04-18 | 2012-09-12 | 河南省电力公司南阳供电公司 | Method for testing dielectric loss and capacitance of capacitance type voltage transformer |
| CN103592518A (en) * | 2013-11-26 | 2014-02-19 | 国家电网公司 | Method for measuring capacitor dielectric loss and capacitance of capacitor voltage transformer |
| CN106153989A (en) * | 2016-07-26 | 2016-11-23 | 桂林电力电容器有限责任公司 | A kind of charged wire-changing device and How It Works |
| CN106483385A (en) * | 2016-12-07 | 2017-03-08 | 北京四方继保自动化股份有限公司 | A kind of dielectric loss measurement system based on punching transformer and measuring method |
| CN107064651A (en) * | 2017-06-07 | 2017-08-18 | 国家电网公司 | It is a kind of adding for without disconnecting power lead test more piece high-voltage capacitor to shield dielectric loss device |
| CN107807258A (en) * | 2017-09-26 | 2018-03-16 | 杭州西湖电子研究所 | A kind of cable connector with double shield function |
| CN108169575A (en) * | 2018-01-16 | 2018-06-15 | 云南电网有限责任公司电力科学研究院 | The test device and method of a kind of CVT capacitances dielectric loss and capacitance |
| CN108226654A (en) * | 2018-01-31 | 2018-06-29 | 深圳供电局有限公司 | Full-automatic dielectric loss measurement system |
| RU2680160C2 (en) * | 2017-03-29 | 2019-02-18 | Акционерное общество энергетики и электрификации "Тюменьэнерго" | Method of diagnostics and monitoring of coupling capacitors technical condition under working voltage |
| CN110749849A (en) * | 2019-10-15 | 2020-02-04 | 国网山东省电力公司淄博供电公司 | Capacitance voltage transformer dielectric loss and capacitance testing system and method |
| RU2713161C1 (en) * | 2019-07-11 | 2020-02-04 | Общество с ограниченной ответственностью "Уральский завод новых технологий" | Connection filter with integrated communication capacitor monitoring sensor |
| CN111239671A (en) * | 2020-03-12 | 2020-06-05 | 国电大渡河检修安装有限公司 | Method for measuring capacitance and dielectric loss value of upper-node coupling capacitor of CVT (constant-Voltage Transformer) |
| RU2734541C1 (en) * | 2020-04-16 | 2020-10-20 | Общество с ограниченной ответственностью "Уральский завод новых технологий" | Communication capacitors state monitoring system |
| CN112630542A (en) * | 2020-10-30 | 2021-04-09 | 国网宁夏电力有限公司 | Loss test method, medium and system of filter capacitor |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010071905A (en) * | 2008-09-22 | 2010-04-02 | Sumitomo Heavy Ind Ltd | Method and device of measuring capacitance of electric double layer capacitor |
| CN101706535A (en) * | 2009-12-09 | 2010-05-12 | 山西省电力公司电力科学研究院 | Device and method for testing dielectric loss of high voltage transformer |
-
2010
- 2010-12-24 CN CN2010106032489A patent/CN102116803A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010071905A (en) * | 2008-09-22 | 2010-04-02 | Sumitomo Heavy Ind Ltd | Method and device of measuring capacitance of electric double layer capacitor |
| CN101706535A (en) * | 2009-12-09 | 2010-05-12 | 山西省电力公司电力科学研究院 | Device and method for testing dielectric loss of high voltage transformer |
Non-Patent Citations (1)
| Title |
|---|
| 马明等: "耦合电容器不拆高压引线试验方法研究", 《电力电容器与无功补偿》 * |
Cited By (20)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102662110B (en) * | 2012-04-18 | 2014-08-06 | 国家电网公司 | Method for testing dielectric loss and capacitance of capacitance type voltage transformer |
| CN102662110A (en) * | 2012-04-18 | 2012-09-12 | 河南省电力公司南阳供电公司 | Method for testing dielectric loss and capacitance of capacitance type voltage transformer |
| CN103592518A (en) * | 2013-11-26 | 2014-02-19 | 国家电网公司 | Method for measuring capacitor dielectric loss and capacitance of capacitor voltage transformer |
| CN106153989A (en) * | 2016-07-26 | 2016-11-23 | 桂林电力电容器有限责任公司 | A kind of charged wire-changing device and How It Works |
| CN106153989B (en) * | 2016-07-26 | 2022-12-06 | 桂林电力电容器有限责任公司 | Live line changing device and operation method |
| CN106483385A (en) * | 2016-12-07 | 2017-03-08 | 北京四方继保自动化股份有限公司 | A kind of dielectric loss measurement system based on punching transformer and measuring method |
| CN106483385B (en) * | 2016-12-07 | 2019-04-26 | 北京四方继保自动化股份有限公司 | A kind of dielectric loss measurement system and measurement method based on punching mutual inductor |
| RU2680160C2 (en) * | 2017-03-29 | 2019-02-18 | Акционерное общество энергетики и электрификации "Тюменьэнерго" | Method of diagnostics and monitoring of coupling capacitors technical condition under working voltage |
| CN107064651A (en) * | 2017-06-07 | 2017-08-18 | 国家电网公司 | It is a kind of adding for without disconnecting power lead test more piece high-voltage capacitor to shield dielectric loss device |
| CN107807258A (en) * | 2017-09-26 | 2018-03-16 | 杭州西湖电子研究所 | A kind of cable connector with double shield function |
| CN107807258B (en) * | 2017-09-26 | 2023-04-28 | 杭州西湖电子研究所 | Cable connector with double shielding function |
| CN108169575A (en) * | 2018-01-16 | 2018-06-15 | 云南电网有限责任公司电力科学研究院 | The test device and method of a kind of CVT capacitances dielectric loss and capacitance |
| CN108169575B (en) * | 2018-01-16 | 2020-07-17 | 云南电网有限责任公司电力科学研究院 | Method for testing dielectric loss and capacitance of CVT capacitor |
| CN108226654A (en) * | 2018-01-31 | 2018-06-29 | 深圳供电局有限公司 | Full-automatic dielectric loss measurement system |
| RU2713161C1 (en) * | 2019-07-11 | 2020-02-04 | Общество с ограниченной ответственностью "Уральский завод новых технологий" | Connection filter with integrated communication capacitor monitoring sensor |
| CN110749849A (en) * | 2019-10-15 | 2020-02-04 | 国网山东省电力公司淄博供电公司 | Capacitance voltage transformer dielectric loss and capacitance testing system and method |
| CN111239671A (en) * | 2020-03-12 | 2020-06-05 | 国电大渡河检修安装有限公司 | Method for measuring capacitance and dielectric loss value of upper-node coupling capacitor of CVT (constant-Voltage Transformer) |
| RU2734541C1 (en) * | 2020-04-16 | 2020-10-20 | Общество с ограниченной ответственностью "Уральский завод новых технологий" | Communication capacitors state monitoring system |
| CN112630542A (en) * | 2020-10-30 | 2021-04-09 | 国网宁夏电力有限公司 | Loss test method, medium and system of filter capacitor |
| CN112630542B (en) * | 2020-10-30 | 2022-05-20 | 国网宁夏电力有限公司 | Loss test method, medium and system for filter capacitor |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102116803A (en) | Method for testing capacitance and dielectric loss value of 220KV coupling capacitor | |
| CN104267368B (en) | A kind of current transformer for metering secondary circuit failure monitoring method | |
| WO2014075584A1 (en) | Method for in-situ detection of partial discharge of damped oscillation wave of large-length ultrahigh-voltage crosslinked cable | |
| CN104215835A (en) | Automatic measuring system for main transformer | |
| CN101592701A (en) | Direct-current voltage withstanding test method for multilevel zinc oxide lightning arresters | |
| CN105203930A (en) | Partial discharge test platform and method for high-voltage switch cabinet | |
| CN205404682U (en) | Wireless phase synchronization device | |
| CN108037430A (en) | A kind of 10kV distribution transformers three-phase partial discharge test system | |
| CN203732677U (en) | Insulation state detection apparatus of all-insulation tubular busbar | |
| CN111123050B (en) | Transformer partial discharge test device for transformer and GIS in GIL connection mode | |
| CN109164363A (en) | A kind of 1000kV reactor local discharge test device and method | |
| CN103743993B (en) | A kind of method detecting deformation of transformer winding | |
| CN105629145A (en) | 10KV insulation tube bus ultrahigh frequency partial discharge detection device | |
| CN210109220U (en) | High-impedance transformer simulation loaded through-flow test device | |
| CN202649391U (en) | Cable defect simulation test system | |
| CN101034125B (en) | Resonant experimental device of dry-type power transformer partial discharge detection | |
| CN207067321U (en) | High altitude localities 750kV shunt reactor Partial Discharge Testing on Site devices | |
| CN106706988B (en) | Multifunctional coupling capacitance voltage divider for partial discharge test of transformer | |
| CN109946571A (en) | The method for carrying out voltage transformer induced over voltage withstand test using relay-protection tester | |
| CN104237639A (en) | Online monitoring method of insulation state of medium-voltage power cable based on impact impedance characteristic parameter | |
| CN207380190U (en) | A kind of iron core reactor turn-to-turn defect tests circuit | |
| CN107436399A (en) | High altitude localities 750kV shunt reactor local discharge test devices | |
| CN204028293U (en) | A kind of non-power frequency operating mode GIS equipment partial discharge defects simulation device | |
| CN206920546U (en) | A kind of wiring construction of low-pressure side two-winding transformer partial discharge test | |
| CN203365519U (en) | Sampling device for high-voltage bushing electrified detection test |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20110706 |