JP3923257B2 - Insulation deterioration diagnosis method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for diagnosing insulation deterioration of an insulator formed of a solid such as a circuit breaker or a rotating electrical machine coil.
[0002]
[Prior art]
In a solid insulator such as a circuit breaker or a rotating electric machine coil, deterioration proceeds due to stress factors during use. It is important to diagnose such a deterioration state and prevent an accident beforehand.
[0003]
As a conventional insulation deterioration diagnosis method, for example, there is a method as described in IEEJ Technical Report (Part II) No. 402 “Insulation Diagnosis Technology During Operation of Power Equipment”. Generally, methods based on electrical characteristics such as insulation resistance, dielectric loss tangent, and partial discharge characteristics are widely used. However, this method is used to measure changes in the electrical characteristics of a deteriorated insulator. Therefore, since it is indirect and greatly affected by noise, there is a problem that sensitivity is not sufficient and accuracy is low.
[0004]
On the other hand, as a method of measuring the chemical change of the insulator, diagnosis based on color difference (ΔE) and brightness is also performed (the above technical report p65), but conventionally, as described in the above-mentioned document, thermal stress It was only targeted for deterioration.
[0005]
[Problems to be solved by the invention]
However, from the case of troubles such as circuit breakers, it was found that deterioration does not proceed due to thermal stress, but progresses due to electrical, chemical, and environmental stress factors.
[0006]
That is, the surface leakage current of the insulator increases when a pollutant adheres to the surface of the insulator and is wetted by rain or the like or when salt water adheres. Due to the local heating by this leakage current, a part of the insulator surface is dried and the leakage current is cut off. The voltage at that portion increases and local discharge occurs. The nitric acid generated by this discharge adheres to the insulator surface, dissolves in the surface adsorbed water, and is ionized, thereby further increasing the leakage current.
[0007]
If the insulator is an organic substance, carbonization proceeds at the portion where the discharge is generated, and a carbonized conductive path is formed (tracking deterioration). Further, when the insulator is an inorganic substance, there is a problem in that the surface resistance is lowered while the discharge is repeated, and a fouling creeping flashover occurs.
[0008]
Further, in a circuit breaker or the like, there has been a problem that an arc or spark is generated every time the circuit is operated, and the insulator is exposed to them and gradually deteriorates to form a carbonized conductive path.
[0009]
Therefore, it is important to detect a state in which the deterioration of the insulator progresses due to the above-mentioned electrical, chemical, and environmental stress factors. Furthermore, it is not only targeted for thermal stress as in the past, but electrical, chemical and environmental stress factors affect the degradation in a complex manner, so multiple degradation characteristics are measured and comprehensively judged. There is a need.
[0010]
The present invention has been made to solve the above-mentioned problems, and can make a diagnosis in accordance with insulation deterioration in which electrical, chemical, and environmental stress factors are combined, and has a plurality of deterioration characteristics. An object of the present invention is to obtain a method for diagnosing insulation deterioration that can be comprehensively detected by measuring.
[0011]
[Means for Solving the Problems]
According to a first aspect of the present invention, there is provided a method for diagnosing insulation deterioration , the step of immersing an ion test paper in pure water, the step of removing excess pure water, and contacting the ion test paper containing the pure water with the surface of the insulator. The step of measuring, the step of measuring the ion concentration of the ionic substance adhering to the surface of the insulator based on the changed color of the ion test paper, and the correlation between the previously determined ion concentration and the degree of insulation deterioration, And detecting an insulation deterioration of the insulator from the measured ion concentration of the ionic substance .
[0012]
In the insulation deterioration diagnosis method according to claim 2 of the present invention, the ionic substance is nitrate ion, sulfate ion, or chlorine ion .
[0013]
In the insulation deterioration diagnosis method according to claim 3 of the present invention, the ionic substance is nitrate ion, sulfate ion, and chlorine ion.
[0014]
According to a fourth aspect of the present invention, there is provided an insulation deterioration diagnosis method comprising: immersing an ion test paper in pure water; removing excess pure water; and contacting the ion test paper containing the pure water with an insulator surface. The step of measuring the ion concentration of the plurality of ionic substances adhering to the surface of the insulator based on the changed color of the ion test paper, and the measurement result of the ion concentration of the plurality of ionic substances. And evaluating the object, taking into account the variation and correlation of the evaluation, and expressing it with one index, and diagnosing insulation deterioration based on the index .
[0015]
In the insulation deterioration diagnosis method according to claim 5 of the present invention, the diagnosis step includes measurement results of ion concentrations of the plurality of ionic substances, gloss of the surface of the insulator, components by infrared spectrophotometer, sodium ion concentration evaluating one of these measurement results and the insulation material, taking into account the variation and correlation evaluation expressed by one index, but you diagnose insulation deterioration on the basis of the index.
[0016]
In the insulation deterioration diagnosis method according to claim 6 of the present invention, the index is a Mahalanobis distance.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
An insulation deterioration diagnosis method according to Embodiment 1 of the present invention will be described with reference to the drawings. 1, FIG. 2, FIG. 3 and FIG. 4 are diagrams showing each procedure of the insulation deterioration diagnosis method according to Embodiment 1 of the present invention. In addition, in each figure, the same code | symbol shows the same or equivalent part.
[0018]
1 to 3, 1 is an ion test paper, 2 is a beaker, 3 is pure water, 4 is an ion test paper containing pure water, 5 is a detection portion of the ion test paper containing pure water, and 6 is insulated. 7 is a detection portion of the discolored ion test paper, and 8 is a colorimetric table.
[0019]
This ionic test paper 1 is commercially available for another purpose of use, and the lower half is the part that reacts. In addition, three types of ion test paper 1 for nitrate ion, sulfate ion, and chlorine ion are prepared.
[0020]
The pure water 3 means ion-exchanged water that does not contain ions.
[0021]
FIG. 4 is a diagram showing the relationship between the surface resistance of the insulator and the ion concentration of nitrate ions. In addition, the relationship between the surface resistance and the ion concentration of sulfate ion or chlorine ion shows the same tendency. The relationship between the three types of total ion concentrations of nitrate ion, sulfate ion, and chloride ion shows the same tendency.
[0022]
Next, the procedure of the insulation deterioration diagnosis method according to the first embodiment will be described with reference to the drawings. In addition, although the case where the ion test paper 1 for nitrate ions is used is described, the same applies to the case where the ion test paper 1 for sulfate ions or chlorine ions is used. Further, the same applies when the above three types of ion test paper 1 are used simultaneously.
[0023]
1 to 4 show procedures 1 to 4 for making an insulation deterioration diagnosis based on the concentration of an ionic substance adhering to the surface of the insulator.
[0024]
First, as procedure 1, as shown in FIG. 1, ion test paper 1 for nitrate ions is immersed in pure water 3 in beaker 2, and excess pure water is removed at the edge of beaker 2.
[0025]
Next, as procedure 2, as shown in FIG. 2, the detection portion 5 of the ion test paper 4 containing pure water 3 is pressed against the surface of the insulator 6 for about 30 seconds. The detection portion 5 of the ion test paper 4 may be placed on the surface of the insulator 6 for about 30 seconds.
[0026]
Next, as shown in FIG. 3, as shown in FIG. 3, the detection portion 7 of the ion test paper 1 discolored according to the ion concentration adhering to the insulator 6 is compared with the colorimetric table 8 to obtain the ion concentration. Ask. This colorimetric table 8 is attached to the ion test paper 1 that is commercially available. For example, when the color of the detection portion 7 is white, the ion concentration is 0, and the color of the detection portion 7 is pinkish purple. In this case, the ion concentration is 500.
[0027]
Then, as shown in FIG. 4, as shown in FIG. 4, nitrate ion ions obtained from an initial insulator (new) and an insulator of a circuit breaker actually used in the market (with or without carbonized conductive path) Find the correlation between concentration and insulation degradation.
[0028]
In FIG. 4, the horizontal axis indicates the degree of insulation deterioration (surface resistance (Ω)), and the vertical axis indicates the ion concentration of nitrate ions, showing a good correlation. In the figure, the surface resistance is larger in the right direction and smaller in the left direction. In the figure, the ion concentration is higher in the upper direction and lighter in the lower direction. The rightmost plot lump (s) is a new insulator, and the plot on the left side of them is the insulator of the breaker actually used.
[0029]
From the relationship between the nitrate ion ion concentration of the unknown insulator 6 obtained by the above steps 1 to 3 and the previously determined nitrate ion ion concentration and insulation deterioration as shown in FIG. Diagnose. In FIG. 4, for example, the two leftmost plots diagnose that the surface resistance is very small and the insulation has deteriorated.
[0030]
That is, the insulation deterioration diagnosis method according to the first embodiment measures the concentration of ionic substances adhering to the insulator surface and diagnoses the insulation deterioration from the correlation between the previously determined ion concentration and insulation deterioration. It is. The ion concentration of nitrate ions adhering to the insulator surface is measured, and the insulation deterioration is diagnosed from the correlation between the previously determined ion concentration and the insulation deterioration. Nitrate ion test paper containing pure water was pressed against the surface of the insulator, the concentration was measured by discoloration of the test paper, and insulation deterioration was diagnosed from the correlation between the previously determined ion concentration and insulation deterioration. .
[0031]
As described above, the case where the insulation deterioration is diagnosed with the ion concentration of nitrate ions has been described. However, the insulation deterioration can be similarly diagnosed with the ion concentration of sulfate ions or chlorine ions. Furthermore, insulation deterioration can be similarly diagnosed by the total ion concentration of nitrate ion, sulfate ion, and chlorine ion.
[0032]
As described above, according to the first embodiment, it is possible to make a diagnosis in conformity with insulation deterioration in which electrical, chemical, and environmental stress factors are combinedly affected.
[0033]
Embodiment 2. FIG.
An insulation deterioration diagnosis method according to Embodiment 2 of the present invention will be described with reference to the drawings. FIG. 5 is a diagram showing the relationship between the surface resistance and the Mahalanobis distance in the insulation deterioration diagnosis method according to Embodiment 2 of the present invention.
[0034]
In other words, Fig. 5 shows the results of analysis of each ion concentration measurement result of nitrate ion, sulfate ion, and chloride ion using the Mahalanobis-Taguchi system method. This shows the correlation with insulation deterioration (surface resistance).
[0035]
By evaluating the insulator in the initial state (new article) and the insulator of the circuit breaker actually used in the market (with and without carbonized conductive path), each ion concentration was obtained and the Mahalanobis distance was calculated.
[0036]
In FIG. 5, the horizontal axis represents the degree of insulation deterioration (surface resistance (Ω)), and the vertical axis represents the Mahalanobis distance, showing a good correlation. In the figure, the surface resistance is larger in the right direction and smaller in the left direction. The Mahalanobis distance is larger in the upper direction and smaller in the lower direction in the figure. The rightmost plot block (a plurality of circles) is a new insulator, and the plot on the left side is an actually used insulator of the circuit breaker.
[0037]
The Mahalanobis distance calculated from the three types of ion concentration measurement results of nitrate ion, sulfate ion, and chloride ion of the insulator whose degree of deterioration is unknown, which is obtained by the method of the first embodiment shown in FIGS. Then, the insulation deterioration is diagnosed from the relationship shown in FIG.
[0038]
In addition to the above ion concentrations, there are evaluation methods that correlate with insulation degradation that is influenced by electrical, chemical, and environmental stress factors in combination. In addition, gloss measurement of insulator surfaces and component analysis using infrared spectrophotometers ( Hydrocarbon absorption peak) and sodium ion concentration measurement. The three types of ion concentrations of nitrate ion, sulfate ion, and chlorine ion, the Mahalanobis distance calculated from the evaluation results of the gloss measurement, component analysis, and sodium ion concentration measurement, and the relationship of FIG. 5 obtained in advance. It is also possible to perform insulation deterioration diagnosis from the same correlation.
[0039]
That is, the insulation deterioration diagnosis method according to the second embodiment evaluates the initial state of the insulator and the state after a predetermined time by a plurality of chemical methods, and uses one index that takes into account the variation and correlation of the evaluation. This is a diagnosis of insulation deterioration from the correlation between the index and the insulation deterioration obtained in advance. In other words, the initial state of the insulator and the state after a predetermined time are evaluated by a plurality of chemical methods, and the evaluation result is expressed by the Mahalanobis distance, which is one index that takes into account variations and correlations by the Mahalanobis Taguchi system method. The insulation deterioration is diagnosed from the correlation between the index obtained in advance and the insulation deterioration.
[0040]
As described above, according to the second embodiment, it is possible to make a diagnosis in conformity with insulation deterioration in which electrical, chemical, and environmental stress factors are combined. Furthermore, since a plurality of deterioration characteristics are measured and comprehensively determined in consideration of variations and correlations, a highly accurate insulation deterioration diagnosis can be performed.
[0041]
【The invention's effect】
As described above, the insulation deterioration diagnosis method according to claim 1 of the present invention includes a step of immersing an ion test paper in pure water, a step of removing excess pure water, and an ion test paper containing the pure water. A step of contacting the surface of the insulator, a step of measuring the ion concentration of the ionic substance adhering to the surface of the insulator based on the changed color of the ion test paper, and a correlation between the previously determined ion concentration and the degree of insulation deterioration. And detecting the insulation deterioration of the insulator from the measured ionic concentration of the ionic substance based on the relationship, so that the insulation deterioration caused by the combined influence of electrical, chemical, and environmental stress factors is included. This makes it possible to make a diagnosis.
[0042]
In the insulation deterioration diagnosis method according to claim 2 of the present invention, as described above, since the ionic substance is nitrate ion, sulfate ion or chlorine ion, there are electrical, chemical and environmental stress factors. This has the effect of making it possible to make a diagnosis in conformity with the insulation deterioration that affects the combined effects.
[0043]
In the insulation deterioration diagnosis method according to claim 3 of the present invention, as described above, since the ionic substance is nitrate ion, sulfate ion and chlorine ion, there are electrical, chemical and environmental stress factors. This has the effect of making it possible to make a diagnosis in conformity with the insulation deterioration that affects the combined effects.
[0044]
As described above, the insulation deterioration diagnosis method according to claim 4 of the present invention includes a step of immersing an ion test paper in pure water, a step of removing excess pure water, and an ion test paper containing the pure water. Contacting the insulator surface; measuring ion concentrations of a plurality of ionic substances adhering to the insulator surface based on the changed color of the ionic test paper; and ionic concentrations of the plurality of ionic substances Insulation is evaluated based on the measurement results, and is represented by one index taking into account the variation and correlation of the evaluation, and includes the step of diagnosing insulation deterioration based on the index. A plurality of deterioration characteristics can be measured and comprehensively determined, and an effect of enabling highly accurate insulation deterioration diagnosis is obtained.
[0045]
In the insulation deterioration diagnosis method according to claim 5 of the present invention, as described above, the diagnosis step uses the measurement results of the ion concentration of the plurality of ionic substances, the gloss of the insulator surface, and the infrared spectrophotometer. component, by any one of the measurement results of the sodium ion concentration to evaluate the insulation, taking into account the variation and correlation evaluation expressed by one index, so you diagnose insulation deterioration on the basis of the index, the evaluation By taking into account variations and correlations, a plurality of deterioration characteristics can be measured and comprehensively determined, and an effect of enabling highly accurate insulation deterioration diagnosis is obtained.
[0046]
In the insulation degradation diagnosis method according to claim 6 of the present invention, as described above, since the index is the Mahalanobis distance, it is possible to comprehensively judge by measuring a plurality of degradation characteristics in consideration of variation in evaluation and correlation. Thus, there is an effect that a highly accurate insulation deterioration diagnosis becomes possible.
[Brief description of the drawings]
FIG. 1 is a diagram showing an initial procedure of an insulation deterioration diagnosis method according to Embodiment 1 of the present invention.
FIG. 2 is a diagram showing a second procedure of the insulation deterioration diagnosis method according to the first embodiment of the present invention.
FIG. 3 is a diagram showing a third procedure of the insulation deterioration diagnosis method according to the first embodiment of the present invention.
FIG. 4 is a diagram showing a relationship between surface resistance and ion concentration in the insulation deterioration diagnosis method according to Embodiment 1 of the present invention.
FIG. 5 is a diagram showing the relationship between the surface resistance and the Mahalanobis distance in the insulation deterioration diagnosis method according to Embodiment 1 of the present invention;
[Explanation of symbols]
1 ion test paper, 2 beakers, 3 pure water, 5 ion test paper detection part, 6 insulator, 8 colorimetric table.

Claims (6)

Immersing the ion test paper in pure water;
Removing excess pure water;
Bringing the ion test paper containing pure water into contact with an insulator surface;
Measuring an ion concentration of an ionic substance adhering to the insulator surface based on the changed color of the ion test paper;
And a step of detecting insulation deterioration of the insulator from the measured ion concentration of the ionic substance based on a correlation between an ion concentration obtained in advance and an insulation deterioration degree . 2. The insulation deterioration diagnosis method according to claim 1 , wherein the ionic substance is nitrate ion, sulfate ion, or chlorine ion . The ionic substance, nitrate ions, insulation degradation diagnosis method of claim 1 Symbol mounting, characterized in that a sulfate ion, and chlorine ion. Immersing the ion test paper in pure water;
Removing excess pure water;
Bringing the ion test paper containing pure water into contact with an insulator surface;
Measuring ion concentrations of a plurality of ionic substances attached to the insulator surface based on the changed color of the ion test paper;
Evaluating an insulator based on the measurement results of the ion concentrations of the plurality of ionic substances, expressing the evaluation by one index taking into account variations and correlation of the evaluation, and diagnosing insulation deterioration based on the index;
Insulation degradation diagnosis how to comprising a. The diagnostic step includes
The insulator is evaluated based on the measurement result of the ion concentration of the plurality of ionic substances and the measurement result of the gloss of the insulator surface, the component by the infrared spectrophotometer, or the sodium ion concentration, and the variation or correlation of the evaluation. the taking into account expressed in one index, insulation degradation diagnosis method according to claim 4, wherein the you diagnose insulation deterioration on the basis of the index. The insulation degradation diagnosis method according to claim 4 or 5, wherein the index is Mahalanobis distance.

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