CN104597340B - Low-temperature electrical characteristics testing device for air - Google Patents
Low-temperature electrical characteristics testing device for air Download PDFInfo
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- CN104597340B CN104597340B CN201410826487.9A CN201410826487A CN104597340B CN 104597340 B CN104597340 B CN 104597340B CN 201410826487 A CN201410826487 A CN 201410826487A CN 104597340 B CN104597340 B CN 104597340B
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Abstract
The invention belongs to the technical field of high voltage and insulation, and in particular relates to a low-temperature electrical characteristics testing device for air. The device mainly comprises a testing chamber, a vacuum pumping device, an air charging device, a cold source copper tube, a hot source copper wire, a temperature monitoring device and a heat insulation chamber which are connected according to the relation that the cold source copper tube and the heat source copper wire closely coil the testing chamber and integrally arranged in the heat insulation chamber; the testing chamber is connected with the vacuum pumping device and the air charging device; the heat source copper wire is connected with the temperature monitoring device; the vacuum pumping device is used for pumping vacuum for the testing chamber in order to prepare for charging the tested air into the testing chamber; the air charging device is used for charging the tested air into the testing chamber; the cold source copper tube is used for cooling the testing chamber; the heat source copper wire supplies heat to the testing chamber to enable adjustable temperature of the testing chamber; the temperature monitoring device controls the heat of the heat source copper wire so as to control and stable the temperature of the testing chamber; the heat insulation chamber comprises two vacuum chambers which can insulate the heat exchange between the testing chamber and the outside, and therefore, the cooling efficiency is increased. According to the device, a test platform is provided for testing the electrical characteristics in a common cold temperature area in which air is at the temperature from -153 to -30 DEG C.
Description
Technical field
The invention belongs to high voltage and insulation technology field, more particularly to a kind of gas low temperature electrical characteristic test device.
Background technology
SF6Gas is current optimal insulation and arc-extinguishing medium, is widely used in Electric Power Equipment Insulation.But SF6It is point
The son larger heavy gas of amount, the more general common gases of condensing temperature are high, pressure is larger, temperature is crossed under low environment, easily liquefaction,
Therefore SF6Gas is not suitable for extremely frigid zones.Solve extremely frigid zones SF6This problem that gas is present, method be
The common gases such as N2, CO2 or air are added to constitute binary mixture in SF6.
On the other hand, SF6 is a kind of very strong greenhouse gases, and the replacement gas for finding SF6 also becomes research both at home and abroad
Focus.In Refrigeration and Cryogenic Engineering, typically general cold warm area is defined on 120K to normal temperature（- 153 DEG C~normal temperature）.At present,
To SF6 substitute gas research be mainly more than -30 DEG C under conditions of, it has been found that replacement gas of good performance（Such as c-
C4F8、CF3I）Condensing temperature be even higher than SF6 gases, and because temperature factor itself also can be produced to gas-insulated performance
It is raw to affect, thus, achievement in research -153 DEG C~-30 DEG C general cold warm area and do not apply to.
In the extremely frigid zones of China, temperature is minimum reachable -30 DEG C~-40 DEG C, sets in superconducting power device current feed etc.
The temperature of the standby changeover portion from normal temperature to liquid nitrogen temperature can be related at -153 DEG C~-30 DEG C in a big way, in order to solve these
The gas-insulated problem of Code in Hazardous Special Locations, studying the insulating properties of gas and admixture of gas under general cold warm area that substitute of SF6 is
It is very necessary.Low temperature, the environment of High Voltage that can be simulated in gas-insulated application of the invention is gas at -153 DEG C to -30
DEG C general cold warm area under electrical characteristic test provide test platform.
The content of the invention
In order to the test for giving gas electrical characteristic under general cold warm area is provided, a temperature-controllable is adjustable, and electrode spacing is quantitative
It is adjustable and and be resistant to High Voltage test device, the invention provides a kind of gas low temperature electrical characteristic test device.
The gas low temperature electrical characteristic device, mainly including test chamber, vacuum extractor, aerating device, low-temperature receiver copper pipe,
Thermal source copper wire, device for monitoring temperature and heat-insulation chamber.Annexation between its each several part is：Low-temperature receiver copper pipe and thermal source copper wire are tight
Around test chamber, one is placed in heat-insulation chamber, and test chamber is connected respectively with vacuum extractor, aerating device；Thermal source copper wire with
Device for monitoring temperature is connected.Vacuum extractor is vacuumized to test chamber, is that test chamber is filled with tested gas and prepares；Inflation
Device to test chamber is filled with tested gas；Low-temperature receiver copper pipe is cooled down to test chamber；Thermal source copper wire provides heat for test chamber,
Make test chamber temperature adjustable；Device for monitoring temperature is controlled to the heat of thermal source copper wire, and then controls and steady testing chamber
Temperature；Heat-insulation chamber can intercept test chamber and carry out heat exchange with the external world, improve cooling effectiveness.
The test chamber includes test chamber, upper top cover, test electrode and watch window.The test chamber is a diameter
It is highly 200mm for 200mm, cavity wall thickness is the stainless steel cylindrical drum of 3mm.The material of the upper top cover adopts polytetrafluoroethyl-ne
There is a handwheel in alkene, central authorities, for adjusting the stroke of the high-field electrode, so as to change the electrode spacing of the test electrode,
And then enable electrode spacing quantitative adjustable in a sealed meter environment.The Circularhole diameter of the watch window is 100mm, using intensity
The good safety glass sealing of high, security, can observe the discharge scenario of test intracavity gas.
The connector of the vacuum extractor and aerating device adopts ball valve using threaded connection mouth, the valve of connector,
Enable test chamber vacuum negative pressure resistant strong, the normal pressure of 0.1MPa to 0.8MPa is resistant to again.The vacuum extractor is using machinery
Pump, the pressure container apparatus that the aerating device is carried using tested gas so make easy to operation.
The material of the low-temperature receiver copper pipe and thermal source copper wire is the red copper with excellent thermal conductivity energy, tightly around outside test chamber
Wall, can provide uniform low-temperature receiver and thermal source for test chamber, reduce the convection current of the gas in test chamber, and effectively improve experiment has
Effect property and accuracy.The internal diameter of the low-temperature receiver copper pipe is 10mm, when thickness of pipe wall is 1mm, temperature adjustment or temperature control, is passed through in low-temperature receiver copper pipe
Liquid nitrogen, is reduced test chamber temperature；A diameter of 3mm of the thermal source copper wire, is provided with the heating of power adjustable on copper wire
Device.
The device for monitoring temperature includes temperature collecting device and temperature control equipment.The temperature collecting device includes two
Individual PT100 temperature sensors, are separately positioned on the test chamber bottom and described high-field electrode, wherein, it is arranged on high pressure
PT100 temperature sensors on electrode are used to do temperature calibration before test, remove during test；Signal processing module, with described two
Individual PT100 temperature sensors electrical connection, to measured temperature voltage signal amplification is filtered；Data collecting card, for gathering
The temperature voltage signal of test chamber bottom and high-field electrode is stated, the output signal of its input termination signal processing module will
The temperature signal is exported to LabView platforms, is shown and is processed, and then feedback output is to the temperature control equipment.
The temperature control equipment is the adjustable device of a heating power, is arranged on the thermal source copper wire, for adjusting the test
The temperature in chamber.
The heat-insulation chamber includes two-layer vacuum chamber, and can intercept test chamber carries out heat exchange with the external world, improves cooling effectiveness；
The vacuum chamber is built-in with multiple pillars, for supporting the test chamber.
Description of the drawings
Fig. 1 is the structural representation of the gas low temperature electrical characteristic test device.
Fig. 2 is the engineering schematic diagram of the gas low temperature electrical characteristic test device.
Fig. 3 is the flow chart of temperature adjusting mode.
Fig. 4 is the flow chart of gas low temperature electrical characteristics test.
Specific embodiment
The invention provides a kind of gas low temperature electrical characteristic test device, right with reference to the accompanying drawings and detailed description
The present invention is described further.
Fig. 1 show the structural representation of the gas low temperature electrical characteristic device, mainly including test chamber, vacuum means
Put, aerating device, low-temperature receiver copper pipe, thermal source copper wire, device for monitoring temperature and heat-insulation chamber.As shown in figure 1, low-temperature receiver copper pipe and thermal source copper
Closely around test chamber, one is placed in heat-insulation chamber silk, and test chamber is connected respectively with vacuum extractor, aerating device；Thermal source
Copper wire is connected with device for monitoring temperature.The material of low-temperature receiver copper pipe and thermal source copper wire is the red copper with excellent thermal conductivity energy,
Tightly around in test cavity outer wall, uniform low-temperature receiver and thermal source can be provided for test chamber, reduce the convection current of the gas in test chamber, be had
Effect improves the validity and accuracy of experiment.The internal diameter of the low-temperature receiver copper pipe is 10mm, when thickness of pipe wall is 1mm, temperature adjustment or temperature control,
Liquid nitrogen is passed through in low-temperature receiver copper pipe, test chamber temperature is reduced；A diameter of 3mm of the thermal source copper wire, is provided with copper wire
When the heater of power adjustable, temperature adjustment or temperature control, the power of heater is adjusted, change the heat that copper wire is passed to, so as to
Temperature in change or steady testing chamber.Heat-insulation chamber includes two-layer vacuum chamber, and can intercept test chamber carries out heat exchange with the external world,
Improve cooling effectiveness；Vacuum chamber is built-in with multiple pillars, for supporting the test chamber.
Vacuum extractor adopts mechanical pump, before inflation, it is desirable to first the test chamber is vacuumized, and vacuum level requirements are 10Pa
Hereinafter, good mechanical pump final vacuum can reach 0.1Pa, disclosure satisfy that vacuum level requirements；Aerating device adopts quilt
The pressure container apparatus that test gas is carried, so make easy to operation.
Fig. 2 show the engineering schematic diagram of the gas low temperature electrical characteristic test device.As shown in Fig. 2 test chamber bag
Include test chamber, upper top cover, test electrode and watch window.Test chamber is that an internal diameter is 200mm, is highly 200mm, cavity wall
Thickness is the stainless steel cylindrical drum of 3mm.Sealing between upper top cover and test chamber main part is using screw tightening and polytetrafluoro
Ethene sealing ring is sealed, and the material of upper top cover adopts polytetrafluoroethylene (PTFE), can seal and can rise heat-blocking action, its
There is a handwheel in central authorities, and for adjusting the stroke of the high-field electrode, handwheel revolves the stroke of the high-field electrode that turns around and changes
1mm, so as to change the electrode spacing of test electrode, and then enables electrode spacing quantitative adjustable in a sealed meter environment.High-tension electricity
Pole, using being threadedly coupled, is convenient for changing test electrode shape with low-field electrode, to change the distribution of test electric field.Watch window
Bore inner diameter be 96mm, extension elongation is 176mm, using the safety glass sealing that intensity is high, security is good, can observe survey
The discharge scenario of examination intracavity gas.It is connected to four-way pipe on observation window, four-way bore is 16mm, four-way pipe each connector difference
It is connected with vacuum extractor, aerating device, vacuum measuring device and device for pressure measurement.Each connector of four-way pipe is equal
Ball valve is adopted using the valve of threaded connection mouth, vacuum extractor and aerating device connector, test chamber vacuum-resistant is born
Pressure, is resistant to the normal pressure of 0.1MPa to 0.8MPa again.Heat-insulation chamber is a vacuum chamber, and can intercept test chamber carries out heat with the external world
Exchange, improve cooling effectiveness.
Fig. 3 show the flow chart of temperature adjusting mode.As shown in figure 3, temperature sensor is PT100 temperature sensors,
Temperature signal is converted into into voltage signal, signal processing module is filtered amplification to measured voltage signal, after process
Voltage signal is sent to data collecting card, is shown and is processed on Labview platforms then, and then feedback output adds to electricity
Thermal.The position of PT100 temperature sensor measurements is respectively the test chamber bottom and described high-field electrode, wherein, if
Putting the PT100 temperature sensors on high-field electrode is used to do temperature calibration before test, removes when being tested；The scale of thermometer
Fixed principle is as follows：Temperature adjusting pair as if test chamber in gas, as shown in Fig. 2 test chamber bottom calorie spread way
Footpath mainly by and low-temperature receiver copper pipe and thermal source copper wire heat transfer, and with test the convection current of intracavity gas, and high-field electrode
Calorie spread approach mainly by the convection current of test chamber indoor gas, when thermal balance is stable, if the temperature of test chamber bottom
It is equal with the temperature of high-field electrode, then it is believed that the temperature of test intracavity gas is also equal to the temperature of both of the above.Enter trip temperature
During demarcation, the temperature curve of test chamber bottom and high-field electrode is recorded, and record the time that both temperature curves start to overlap.
Temperature calibration is carried out different temperature provinces are repeated multiple times, the temperature curve for taking maximum starts the time of coincidence, is designated as t.Test
Before, remove the temperature sensor on high-field electrode.When being tested, when the temperature curve of test chamber bottom is in stable, pass through
After time t, just think that the temperature temperature equal with the temperature of test intracavity gas and test chamber bottom of high-field electrode is equal.
Fig. 4 show the flow chart of gas low temperature electrical characteristics test.First test device is vacuumized, test is then charged with
Gas, is then adjusted to desired value the test device temperature, adjusts electrode spacing, and finally applied voltage is entered on high-field electrode
Row test.After completing once to test, as requested, selection operation mode.If it is desired to same gas difference at the same temperature
Electrode spacing is tested, and only need to adjust electrode spacing；If it is desired to same gas is tested at different temperatures, then need from
Adjust temperature and start operation；If desired change gas or change Different electrodes and grasp again it is necessary to vacuumize beginning from test device
Make.
Claims (5)
1. a kind of gas low temperature electrical characteristic test device, it is characterised in that：Mainly include test chamber, vacuum extractor, inflation
Device, low-temperature receiver copper pipe, thermal source copper wire, device for monitoring temperature and heat-insulation chamber, the annexation between its each several part is：Low-temperature receiver copper pipe
With thermal source copper wire closely around test chamber, one is placed in heat-insulation chamber, and test chamber is connected respectively with vacuum extractor, aerating device
Connect；Thermal source copper wire is connected with device for monitoring temperature；Vacuum extractor is vacuumized to test chamber, is that test chamber is filled with tested gas testing
Body is prepared；Aerating device to test chamber is filled with tested gas；Low-temperature receiver copper pipe is cooled down to test chamber；Thermal source copper wire is survey
Examination chamber provides heat, makes test chamber temperature adjustable；Device for monitoring temperature is controlled to the heat of thermal source copper wire, so control and
The temperature in steady testing chamber；Heat-insulation chamber includes two-layer vacuum chamber, and can intercept test chamber carries out heat exchange with the external world, improves cooling
Efficiency.
2. a kind of gas low temperature electrical characteristic test device according to claim 1, it is characterised in that：The test chamber bag
Test electrode is included, the test electrode includes high-field electrode and low-field electrode, electrode can be quantitatively adjusted in a sealed meter environment again
Spacing.
3. a kind of gas low temperature electrical characteristic test device according to claim 2, it is characterised in that：The monitoring temperature
Device includes temperature collecting device and temperature control equipment, and the temperature collecting device includes two PT100 temperature sensors, point
It is not arranged on the test chamber bottom and described high-field electrode, wherein, the PT100 TEMPs being arranged on high-field electrode
Device is used to do temperature calibration before test, removes during test；Signal processing module, is electrically connected with described two PT100 temperature sensors
Connect, amplification is filtered to measured temperature voltage signal；Data collecting card, for gathering the test chamber bottom and the high pressure
The temperature voltage signal of electrode；The temperature control equipment, is arranged on the thermal source copper wire, for adjusting the test chamber
Temperature.
4. a kind of gas low temperature electrical characteristic test device according to claim 1, it is characterised in that：The vacuum means
Put and adopt ball valve using mouth, the valve of connector is threadedly coupled with the connector of aerating device, test chamber vacuum-resistant is born
Pressure, is resistant to the normal pressure of 0.1MPa to 0.8MPa again.
5. a kind of gas low temperature electrical characteristic test device according to claim 1, it is characterised in that：The low-temperature receiver copper pipe
With thermal source copper wire tightly around in test cavity outer wall, uniform low-temperature receiver and thermal source can be provided for test chamber, reduce the gas in test chamber
The convection current of body, effectively improves the validity and accuracy of experiment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201410826487.9A CN104597340B (en) | 2014-12-26 | 2014-12-26 | Low-temperature electrical characteristics testing device for air |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410826487.9A CN104597340B (en) | 2014-12-26 | 2014-12-26 | Low-temperature electrical characteristics testing device for air |
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| CN104597340A CN104597340A (en) | 2015-05-06 |
| CN104597340B true CN104597340B (en) | 2017-05-17 |
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| CN105891648B (en) * | 2016-06-17 | 2019-02-12 | 华北电力大学 | Measuring device based on SST |
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| CN106872082A (en) * | 2017-04-28 | 2017-06-20 | 中国地震局地壳应力研究所 | A kind of body strain dynamic characteristic measuring instrument and measuring method |
| CN109683075A (en) * | 2019-03-05 | 2019-04-26 | 云南电力技术有限责任公司 | A kind of insulating materials local discharge test device |
| CN110763968B (en) * | 2019-12-06 | 2024-07-19 | 哈尔滨理工大学 | Full-angle visual gas breakdown testing system |
| CN113252773A (en) * | 2021-02-25 | 2021-08-13 | 国网内蒙古东部电力有限公司检修分公司 | Liquefaction temperature test measuring device and method for SF6 gas and mixed insulating gas thereof |
| CN115479614A (en) * | 2022-09-01 | 2022-12-16 | 北京晨晶电子有限公司 | Testing device, system and method of micro-mechanical sensor |
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| JP2616118B2 (en) * | 1990-03-22 | 1997-06-04 | ソニー株式会社 | Low temperature processing method and low temperature processing apparatus |
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