CN107024672B - A kind of SF6The operation scaling method of insulation of electrical installation state on_line monitoring system - Google Patents
A kind of SF6The operation scaling method of insulation of electrical installation state on_line monitoring system Download PDFInfo
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- CN107024672B CN107024672B CN201710283864.2A CN201710283864A CN107024672B CN 107024672 B CN107024672 B CN 107024672B CN 201710283864 A CN201710283864 A CN 201710283864A CN 107024672 B CN107024672 B CN 107024672B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R35/00—Testing or calibrating of apparatus covered by the other groups of this subclass
- G01R35/005—Calibrating; Standards or reference devices, e.g. voltage or resistance standards, "golden" references
- G01R35/007—Standards or reference devices, e.g. voltage or resistance standards, "golden references"
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/1702—Systems in which incident light is modified in accordance with the properties of the material investigated with opto-acoustic detection, e.g. for gases or analysing solids
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/0004—Gaseous mixtures, e.g. polluted air
- G01N33/0006—Calibrating gas analysers
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/1702—Systems in which incident light is modified in accordance with the properties of the material investigated with opto-acoustic detection, e.g. for gases or analysing solids
- G01N2021/1704—Systems in which incident light is modified in accordance with the properties of the material investigated with opto-acoustic detection, e.g. for gases or analysing solids in gases
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- Testing Relating To Insulation (AREA)
Abstract
The invention discloses a kind of SF6The operation scaling method of insulation of electrical installation state on_line monitoring system, on-line monitoring system is demarcated using spare calibration mouth, and it proposes to demarcate postrun on-line monitoring system using least square method, sensor bring error after prolonged use can be reduced as far as possible, guarantee that later period systems stay reliability of operation, this method are suitable for the SO of running sulfur hexafluoride electrical equipment current transformer and breaker2Content and purity on-line monitoring system can monitor moisture, SO simultaneously2The on-line monitoring system of content and purity, GIS optoacoustic spectroscopy decomposition components on-line monitoring system and SF6Distributed on line monitoring system etc. is leaked, with overcome the deficiencies in the prior art.
Description
Technical field
The present invention relates to a kind of operation scaling method of on-line monitoring system, especially a kind of SF6Insulation of electrical installation shape
The operation scaling method of state on-line monitoring system.
Background technique
The development of Adjoint technology, SF6Insulation of electrical installation state on_line monitoring system is more more and more universal, various types
Sensor for monitoring SF6Decomposition product content, SF in gas6Humidity and SF6Gas purity etc., however, all run at the scene
On-line monitoring system used in sensor (include infrared absorption, electrochemical sensor, resistance-capacitance type sensor and optoacoustic light
Spectrum sensor etc.) after using a period of time (long or short), due to the characteristic and optical path of sensor itself and circuit etc.
Will cause data error, operative sensor even causes very big data-bias, it is most likely that cause system alarm too early or
Delayed alarm.Initial calibration no longer can guarantee the accuracy of monitoring data, thus need to the SF after operation a period of time6Electricity
The apparatus insulated state on_line monitoring system of gas is re-scaled.
Patent name are as follows: sulfur hexafluoride inflatable-type breaker insulation state on-line monitoring device, inventor: Zhang Ying, Lee
Army defends, application No. is: 2012205856325, which disclose sulfur hexafluoride inflatable-type breaker state of insulations to supervise online
Device is surveyed, which does not have a power failure can real-time monitoring SF6Breaker moderate purity and decomposition product SO2Content, can real-time monitoring inflatable
The operation conditions of breaker, but since the sulfur hexafluoride inflatable-type breaker insulation state on-line monitoring device of scene operation is
It is once demarcated before putting into operation, after sulfur hexafluoride inflatable-type breaker insulation state on-line monitoring device puts into operation but not
It is demarcated again, it is difficult to guarantee the accuracy of later period monitoring data.
Summary of the invention
The purpose of the present invention: spare calibration mouth is set in original on-line monitoring system, using spare calibration mouth to online prison
Examining system is demarcated, and proposes to demarcate postrun on-line monitoring system using least square method, can be reduced as far as possible
Sensor bring error after prolonged use guarantees later period systems stay reliability of operation, to overcome the prior art
It is insufficient.
The technical scheme is that a kind of SF6The operation scaling method of insulation of electrical installation state on_line monitoring system,
Including the following steps:
The first step, with SF6For the SO of the various concentration of spirit2Gas is as calibrating gas parameter；
Second step, the connection for disconnecting on-line monitoring system and main equipment stop on-line monitoring system operating, to on-line monitoring
System vacuumizes, and is demarcated by the spare calibration mouth being arranged in on-line monitoring system to equipment；
Third step, the successively sequence ascending according to standard gas concentration, fill into on-line monitoring system gas circuit structure
Enter calibrating gas, and records the actually measured data of system；
4th step carries out curve fitting using measured value as abscissa and standard gas concentration as ordinate, is surveyed
The functional relation of magnitude and standard gas concentration；
5th step, the 4th step obtain linear function on the basis of, repeat third step, be filled with again into system by it is small to
The calibrating gas of big concentration, and measured value is obtained, it carries out curve fitting again, obtains new curved line relation expression formula；
6th step repeats the 5th step, and curve matching is repeated, reaches its linear relationship most preferably, and meets error model
It encloses, that is, completes the calibration of system；
The curve matching the following steps are included:
Step 1, according to known one group of measured value, and measured value and standard gas concentration have error, then find out from becoming
Measure the functional relation between X and dependent variable Y, the mathematic(al) representation of function are as follows:
Y=F (X)
In formula: Y is standard gas concentration, and X is measured value；
Step 2 finds out concentration error δ minimum value, the mathematic(al) representation calculated are as follows:
In formula: δ is concentration error, and i is sample introduction or pendulous frequency, and m is the m times sample introduction or measurement, xiFor the measurement of i-th
Value, yiIt is i-th institute into standard gas concentration；
Step 3 using the output of sensor is a kind of linear approximate relationship, need to only be closed using linear in transducer calibration
System is fitted, the mathematic(al) representation of linear relationship fitting are as follows:
Y=KX+B
Wherein, Y is correction value, and X is measured value, and K is amendment proportionality coefficient, and B is amendment deviation factor；
Step 4, according to step 3 and step 2, you can get it
In formula: δ is concentration error, and K is amendment proportionality coefficient, and B is amendment deviation factor, and i is sample introduction or pendulous frequency, m
For the m times sample introduction or measurement, xiFor the measured value of i-th, yiIt is i-th institute into standard gas concentration；
Step 5, a binary function for δ being regarded as independent variable K and B, the mathematic(al) representation of function are as follows:
δ=δ (K, B)；
Step 6, binding test data find out adjusted coefficient K and B, the mathematic(al) representation calculated are as follows:
In formula: δ is concentration error, and K is amendment proportionality coefficient, and B is amendment deviation factor, and i is sample introduction or pendulous frequency, m
For the m times sample introduction or measurement, xiFor the measured value of i-th, yiIt is i-th institute into standard gas concentration；
It is again coupled to after 7th step, calibration with main equipment, recovery system operation.
It is described with SF6For the SO of spirit2Gas is SO as calibrating gas parameter2Gas concentration is respectively 2.45 μ L/
L, 4.5 μ L/L, 4.87 μ L/L, 8.97 μ L/L, 10.76 μ L/L, 46.4 μ L/L and 62.3 μ L/L.
Compared with the prior art, irregularly on-Line Monitor Device is demarcated by spare calibration mouth, while utilizes this
The method that invention provides is demarcated, and this method is suitable for running sulfur hexafluoride electrical equipment current transformer and breaker
SO2Content and purity on-line monitoring system can monitor moisture, SO simultaneously2The on-line monitoring system of content and purity, GIS optoacoustic
Spectral resolution component on-line monitoring system etc., can overcome the prior art.
Detailed description of the invention
Fig. 1 is gas circuit structure schematic diagram of the present invention；
Fig. 2 is matched curve Fig. 1 of the invention；
Fig. 3 is matched curve Fig. 2 of the invention；
Fig. 4 is matched curve Fig. 3 of the invention；
In figure: 6, switch electromagnetic valve, 7, measurement gas chamber, 8, digital pressure gauge, 10, switch electromagnetic valve.
Specific embodiment
The present invention will be further explained below with reference to the attached drawings
As shown in attached drawing 1-4, the sulfur hexafluoride inflatable-type breaker insulation state on-line monitoring device run with early stage is (specially
Sharp ZL201220585632.5) for, after running 1 year and a half, SO2There is biggish error in the data of sensor test.Most
The needs that the calibration curve of first instrument no longer meets monitoring data accuracy can not due to the attenuation characteristic of electrochemical sensor
Calibration, then must re-scale.
With SF6For the SO of spirit2Gas is as calibrating gas, the SO of nameplate mark2Gas concentration is 2.45 μ L/ respectively
L, this 7 kinds of various concentration gases of 4.5 μ L/L, 4.87 μ L/L, 8.97 μ L/L, 10.76 μ L/L, 46.4 μ L/L and 62.3 μ L/L.It connects
The calibration experiment to get off is carried out on the basis of the standard gas concentration.
The connection of disconnection system and main equipment, halt system operating, vacuumizes system, passes through the calibration reserved in device
Mouth calibration 1# machine.
In order to save gas, gas flow space is reduced, therefore demarcates gas circuit and uses structure chart shown in FIG. 1, calibrating gas
It is filled with from the calibrating gas interface of switch electromagnetic valve 6, by measuring 7 (SO of gas chamber2Electrochemical sensor), from switch electromagnetic valve 10
Discharge outlet discharge, may be viewed by gas actual pressure in pipeline from digital pressure gauge 8.
(1) it is inflated into calibration gas circuit structure
I, the successively sequence ascending according to standard gas concentration, gas is filled with into gas circuit structure, and record experiment
Data.Experimental data is as shown in table 1:
1 1# machine experimental result 1 of table
| Serial number | Calibrating gas | Experimental data |
| 0 | 0μL/L | 4.7μL/L |
| 1 | 2.45μL/L | 4.8μL/L |
| 2 | 4.5μL/L | 5.2μL/L |
| 3 | 4.87μL/L | 5.4μL/L |
| 4 | 8.97μL/L | 6.0μL/L |
| 5 | 10.16μL/L | 6.4μL/L |
| 6 | 46.4μL/L | 13.6μL/L |
| 7 | 62.3μL/L | 17.4μL/L |
Calibrating gas and experimental data are carried out curve fitting, the curve of fitting is as shown in Figure 2.
In Fig. 2, using experimental data as abscissa, for calibrating gas parameter as ordinate, the curve being fitted is " series
1 ", the linear relationship curve of standard is " linear (series 1) ".The curved line relation expression formula being fitted is y=4.858x-
21.104。
II, on the basis of curve matching y=4.858x-21.104, it is successively descending according to standard gas concentration
Sequentially, it is filled with gas into gas circuit structure, and records experimental data.Experimental data is as shown in table 2:
2 1# machine experimental result 2 of table
| Serial number | Calibrating gas | Experimental data |
| 0 | 0μL/L | 3.1μL/L |
| 1 | 2.45μL/L | 3.5μL/L |
| 2 | 4.5μL/L | 6.4μL/L |
| 3 | 4.87μL/L | 6.8μL/L |
| 4 | 8.97μL/L | 11.3μL/L |
| 5 | 10.16μL/L | 12.6μL/L |
| 6 | 46.4μL/L | 48.8μL/L |
| 7 | 62.3μL/L | 63.6μL/L |
Calibrating gas and experimental data are carried out curve fitting, the curve of fitting is as shown in Figure 3.
In Fig. 3, the curved line relation expression formula being fitted is y=1.0068x-2.1882.
III, on the basis of curve matching y=1.0068x-2.1882, it is successively ascending according to standard gas concentration
Sequence, gas is filled with into gas circuit structure, and record experimental data.Experimental data is as shown in table 3:
3 1# machine experimental result 3 of table
| Serial number | Calibrating gas | Experimental data |
| 0 | 0μL/L | 0.1μL/L |
| 1 | 2.45μL/L | 0.7μL/L |
| 2 | 4.5μL/L | 3.4μL/L |
| 3 | 4.87μL/L | 3.7μL/L |
| 4 | 8.97μL/L | 7.7μL/L |
| 5 | 10.16μL/L | 8.6μL/L |
| 6 | 46.4μL/L | 43.6μL/L |
| 7 | 62.3μL/L | 61.1μL/L |
Calibrating gas and experimental data are carried out curve fitting, the curve of fitting is as shown in Figure 4.
In Fig. 4, the curved line relation expression formula being fitted is y=1.0147x+1.1067.
In the 3rd curve matching, it has been found that the curve being fitted meets error range closest to straight line, i.e.,
Small concentration error is (- 1,1), and big concentration error is (- 10%, 10%).The calibration of 1# machine finishes.It can meet in operation again
SF6The accuracy of on-line monitoring system detection data.It is again coupled to after calibration with main equipment, recovery system operation.
This method is suitable for the SO of running sulfur hexafluoride electrical equipment current transformer and breaker2Content and purity
On-line monitoring system can monitor moisture, SO simultaneously2The on-line monitoring system of content and purity, GIS optoacoustic spectroscopy decomposition components exist
Line monitoring system etc..
Claims (2)
1. a kind of SF6The operation scaling method of insulation of electrical installation state on_line monitoring system, it is characterised in that: including following several
A step:
The first step, with SF6For the SO of the various concentration of spirit2Gas is as calibrating gas parameter；
Second step, the connection for disconnecting on-line monitoring system and main equipment stop on-line monitoring system operating, to on-line monitoring system
It vacuumizes, equipment is demarcated by the spare calibration mouth being arranged in on-line monitoring system；
Third step, the successively sequence ascending according to standard gas concentration, mark is filled with into on-line monitoring system gas circuit structure
Quasi- gas, and record the actually measured data of system；
4th step carries out curve fitting using measured value as abscissa and standard gas concentration as ordinate, obtains measured value
With the functional relation of standard gas concentration；
5th step, the 4th step obtain linear function on the basis of, repeat third step, be filled with again into system ascending dense
The calibrating gas of degree, and measured value is obtained, it carries out curve fitting again, obtains new curved line relation expression formula；
6th step repeats the 5th step, and curve matching is repeated, reaches its linear relationship most preferably, and meet error range, i.e.,
The calibration of completion system；
The curve matching the following steps are included:
Step 1, according to known one group of measured value, and measured value and standard gas concentration have error, then find out independent variable X with
Functional relation between dependent variable Y, the mathematic(al) representation of function are as follows:
Y=F (X)
In formula: Y is standard gas concentration, and X is measured value；
Step 2 finds out concentration error δ minimum value, the mathematic(al) representation calculated are as follows:
In formula: δ is concentration error, and i is sample introduction or pendulous frequency, and m is the m times sample introduction or measurement, xiFor the measured value of i-th, yi
It is i-th institute into standard gas concentration；
Step 3 using the output of sensor is a kind of linear approximate relationship, in transducer calibration only need to using linear relationship into
Row fitting, the mathematic(al) representation of linear relationship fitting are as follows:
Y=KX+B
Wherein, Y is correction value, and X is measured value, and K is amendment proportionality coefficient, and B is amendment deviation factor；
Step 4, according to step 3 and step 2, you can get it
In formula: δ is concentration error, and K is amendment proportionality coefficient, and B is amendment deviation factor, and i is sample introduction or pendulous frequency, and m is m
Secondary sample introduction or measurement, xiFor the measured value of i-th, yiIt is i-th institute into standard gas concentration；
Step 5, a binary function for δ being regarded as independent variable K and B, the mathematic(al) representation of function are as follows:
δ=δ (K, B)；
Step 6, binding test data find out adjusted coefficient K and B, the mathematic(al) representation calculated are as follows:
In formula: δ is concentration error, and K is amendment proportionality coefficient, and B is amendment deviation factor, and i is sample introduction or pendulous frequency, and m is m
Secondary sample introduction or measurement, xiFor the measured value of i-th, yiIt is i-th institute into standard gas concentration；
It is again coupled to after 7th step, calibration with main equipment, recovery system operation.
2. a kind of SF according to claim 16The operation scaling method of insulation of electrical installation state on_line monitoring system,
It is characterized in that: described with SF6For the SO of spirit2Gas is SO as calibrating gas parameter2Gas concentration is respectively 2.45 μ L/
L, 4.5 μ L/L, 4.87 μ L/L, 8.97 μ L/L, 10.76 μ L/L, 46.4 μ L/L and 62.3 μ L/L.
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| CN113945329B (en) * | 2021-10-14 | 2024-01-23 | 西安西电开关电气有限公司 | SF (sulfur hexafluoride) 6 Method and system for judging gas leakage defect |
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2017
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| CN105628752A (en) * | 2014-11-28 | 2016-06-01 | 国网青海省电力公司电力科学研究院 | Calibration method of electrochemical sensor |
| CN105806898A (en) * | 2016-03-10 | 2016-07-27 | 电子科技大学 | Gas concentration calibration method for gas sensor |
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