JP2019194522A - Manufacturing method of color sample/color difference criteria and deterioration diagnosis method for oil-filled electrical equipment using color difference criteria - Google Patents

Abstract

To provide equipment and deterioration diagnosis methods that can easily and quickly perform deterioration diagnosis of oil-filled electrical equipment.SOLUTION: The degree of deterioration of oil-filled electrical equipment is diagnosed, after draining insulation oil from the oil-filled electrical equipment that is subjected to deterioration diagnosis, or after exposing the insulator to the atmosphere such as by lifting the electrical equipment body, by imaging an insulator that constitutes the oil-filled electrical equipment by adjusting the white balance together with the white color reference, and evaluating the average degree of polymerization by comparing the photographed image with the color sample using the color difference criteria.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for diagnosing a deterioration state of an oil-filled electrical device such as a transformer during maintenance and the like, and a method for producing a standard necessary for the deterioration diagnosis.

  Degradation diagnosis of oil-filled electrical equipment such as transformers is to measure the gas concentration of carbon monoxide, carbon dioxide, etc. in insulating oil, which is a decomposition product of insulating paper, or measure the concentration of furfural in insulating oil. However, these measurements had to be performed with an oil-in-gas measuring device (gas chromatograph) or a furfural measuring device (liquid chromatograph) installed in the analysis room. The extracted insulating oil had to be brought into the analysis room once, and quick analysis was not possible.

  On the other hand, as a means for solving such a problem, there has been proposed an apparatus for irradiating an insulating material with light having a plurality of wavelengths and determining the deterioration of the insulating paper using the reflection absorbance difference or the reflection absorbance ratio ( See Patent Document 1 below). Since the device is portable, it can be taken to the site where a transformer or the like is installed, and the degree of deterioration can be directly analyzed.

Japanese Patent No. 3440759

  However, since the apparatus described in Patent Document 1 diagnoses the degree of deterioration of a material (insulating material) from the difference in reflection absorbance between two wavelengths using an optical fiber sensor, its configuration is special and general. There is a problem that becomes expensive.

  The present invention can solve the above-mentioned problems and provides a method capable of promptly diagnosing deterioration of oil-filled electrical equipment without using an expensive device.

  In the invention of claim 1, the same kind of insulating oil and insulating paper used for oil-filled electrical equipment that is subject to deterioration diagnosis is enclosed in a container under conditions simulating the deterioration prevention specifications of the transformer. When the container is heated and a predetermined heating time elapses, a part of the insulating paper is sampled, the average degree of polymerization is measured from a part of the collected insulating paper, and the collected insulating paper The remainder is a color sample in the measurement value of the average degree of polymerization.

  The invention described in claim 2 is characterized in that the correlation between the hue of the color sample described in claim 1 and the average degree of polymerization is used as a color difference reference.

  The invention described in claim 3 exposes the insulator by removing the insulating oil from the oil-filled electrical device that is the object of deterioration diagnosis, lifting the main body of the electrical device, collecting a part, etc., and claiming the insulator according to claim 1 It is characterized by diagnosing the degree of deterioration of oil-filled electrical equipment by measuring the color difference with the color sample and estimating the average degree of polymerization.

  The invention described in claim 4 exposes the insulator by removing the insulating oil from the oil-filled electrical device that is the object of deterioration diagnosis, lifting the electrical device body, collecting a part, and the like. A white balance is adjusted and an image is taken, and the photographed image is compared with the color swatch according to claim 1 and the average degree of polymerization of the color swatches whose hues are the same or closest is grasped using a color difference criterion. Thus, the present invention is characterized by diagnosing the degree of deterioration of the oil-filled electrical device.

  The invention according to claim 5 is a new article in which insulation oil is removed from oil-filled electrical equipment that is subject to deterioration diagnosis, the electrical equipment body is lifted, a part is taken, etc., and the insulation is exposed and oil-immersed with insulation oil. By photographing the insulating paper under the same conditions, and comparing the color difference between the insulator constituting the oil-filled electrical device and the new insulating paper with the color sample created using the color sample created in claim 2, A method for diagnosing deterioration of an oil-filled electrical device using a color difference criterion, characterized by diagnosing the degree of deterioration of the oil-filled electrical device.

  According to the first aspect of the present invention, the equipment used for the deterioration diagnosis of the oil-filled electrical device can be configured at low cost.

  According to the second aspect of the invention, the deterioration state of the oil-filled electrical device can be easily grasped using the color sample and the color difference standard.

  According to the third to fifth aspects of the present invention, the deterioration diagnosis of the oil-filled electrical equipment can be quickly performed at the site (the place where the oil-filled electrical equipment is installed) using inexpensive equipment.

It is sectional drawing of the color sample preparation device which concerns on the Example of this invention. It is a scatter diagram which shows the correlation of the average degree of polymerization of the insulating paper for every heating time and hue concerning the Example of this invention.

  A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a color sample maker A according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a storage container that constitutes the production device A. The storage container 1 stores insulating paper 2 and insulating oil 3 of the same type as those used in an oil-filled electrical device subject to deterioration diagnosis. Yes.

  4 is a through-hole opened in the flange portion 5 of the storage container 1, and 6 is a lid for closing the upper opening of the storage container 1. 7 is a through-hole of the lid 6 opened at a position corresponding to the through-hole 4 of the flange portion 5, and 8 is an O for being sandwiched between the lid 6 and the flange portion 5 to keep the inside of the container 1 sealed. It is a packing such as a ring.

  Reference numeral 9 denotes a bolt that passes through the through hole 4 and the through hole 7, 10 denotes a plate washer, and 11 denotes a spring washer. A nut 12 is screwed onto the bolt 9 and fastens the container 1 and the lid 2.

  Reference numeral 13 denotes a plurality of vent holes opened in the lid 2 in order to evacuate the air in the storage container 1 or enclose an inert gas, 14 is a vent pipe attached to the vent hole 13, and 15 is a vent pipe 14. It is a valve attached to the tip.

  Next, a method of producing equipment (color difference standard) used for deterioration diagnosis of oil-filled electrical equipment using the production device A having the above configuration will be described.

  The manufacturing device A having the above-described structure has a structure in which the inside of the container 1 can be sealed by the presence of the packing 8, and a space in the container 1 can be operated by connecting a vacuum pump (not shown) to the valve 15 and operating for a certain period of time. To a vacuum.

  Here, in the case where the oil-filled electrical device that is the object of deterioration diagnosis encloses an inert gas, the inside of the storage container 1 is evacuated and then the same type of inert gas is stored via the vent pipe 14. By enclosing in the container 1, the conditions are the same as the environment in the case of the oil-filled electrical device subject to deterioration diagnosis. In the case of pressureless sealing, the upper surface space is kept in a vacuum. If air-sealed, seal the air.

In this state, the preparation device A is put in a thermostat not shown, and heated at, for example, 120 to 140 ° C., for a predetermined time (a time expected to obtain a degree of polymerization as a deterioration diagnosis index based on past empirical rules). Every time elapses, the preparation device A is taken out of the thermostat and cooled to room temperature. The container 1 and the lid 6 may be made of metal, but considering that the container 1 and the lid 6 are heated in a thermostatic bath, it is desirable that the container is made of stainless steel that does not corrode during storage or under the influence of heating.

  The nut 12 and the bolt 9 are removed from the preparation device A taken out from the thermostatic chamber, the lid 6 is opened, and the amount of insulating paper necessary for measuring the average degree of polymerization is taken out from the insulating paper 2 in the container 1.

  After the necessary amount is taken out, the lid 6 is again put on the container 1 and the lid 6 is fastened to the container 1 with bolts 9 and nuts 12. Thereafter, by starting a vacuum pump (not shown), the inside of the container 1 is again evacuated, the insulating paper 2 and the insulating oil 3 in the container 1 are degassed, and in addition, the oil filling When the electric equipment encloses the inert gas, the same kind of inert gas is enclosed.

  Thereafter, the preparation device A is again placed in a thermostatic bath and heated, and once the predetermined time (the time when it is predicted that a degree of polymerization as a deterioration diagnosis index can be obtained by past empirical rules) has passed, the preparation device A is kept at constant temperature. Thereafter, the same operation as described above is repeated.

  On the other hand, the necessary amount of insulation paper taken out is partly degreased and bleached, dissolved in copper ethylenediamine or copper ammonia solution and measured for average polymerization degree by viscosity method, hue and average polymerization of the insulation paper taken out Guide the degree relationship. A method such as GPC (liquid chromatograph) or light scattering may be used to measure the average degree of polymerization of the insulating paper.

  In this manner, the required amount of the insulating paper 2 is taken out every time a predetermined time (a time when it is predicted that a degree of polymerization as a deterioration diagnosis index can be obtained based on past empirical rules). Since the degree of polymerization is measured, the relationship between the hue of the insulating paper 2 and the average degree of polymerization can be derived according to the heating time until it is taken out from the preparation device A.

  Insulating paper excluding a part of the sample (hereinafter referred to as residual insulating paper) is used as a color sample for deterioration diagnosis. In JEM 1463 “Evaluation criteria for average degree of polymerization of insulating paper for transformers”, there are criteria for determining the life level when the average degree of polymerization of the insulating paper is 450 or less and the danger level when the average degree of polymerization is 250 or less. For this reason, it is possible to determine the use limit of the oil-filled electrical device by preparing a color sample having an average degree of polymerization of 250 and an average degree of polymerization of 450 and using it for deterioration diagnosis. Note that the hue of the remaining insulating paper can be clarified by degreasing the remaining insulating paper.

  Here, how the hue of the insulating paper 2 is changed due to the progress of heat deterioration will be described. The insulating paper 2 that was light yellow at first changes from dark yellow to brown as the deterioration due to heating progresses. As the deterioration progresses, the color changes to darker.

  The scatter diagram of FIG. 2 shows the correlation between the average degree of polymerization of insulating paper and the amount of change in hue (the color difference between a new insulating paper and the color sample is referred to as a color difference). As shown in FIG. 2, since the correlation is clear, if the insulating paper constituting the oil-filled electrical device that is the object of deterioration diagnosis is measured with a colorimeter, the oil is obtained using the scatter diagram of FIG. It is possible to determine the degree of deterioration of the input electrical equipment.

  At this time, the relationship between the insulating paper of the oil-filled electrical device and the color sample is as follows: (1) When the insulating paper is oil-immersed and the color sample is non-oil-immersed, (2) The insulating paper is oil-immersed and the color sample is also In the case of oil immersion, (3) when the insulating paper is non-oil-immersed and the color sample is also non-oil-immersed, (4) the insulating paper is non-oil-immersed and the color sample is oil-immersed. Since the insulating paper is immersed in the insulating oil of the oil-filled electrical device, diagnosis is generally performed using the relationship of the color difference in the case of (1) or (2). If the situation allows, the insulation paper of the transformer and the color sample are degreased and both are made non-oil-immersed so that the hue becomes clear and the color difference between the two becomes clear. be able to.

  Next, a specific example of the deterioration diagnosis method according to the second embodiment of the oil-filled electrical apparatus that is a deterioration diagnosis target will be described. First, drain the insulation oil from the oil-filled electrical equipment that is subject to degradation diagnosis, lift the electrical equipment body, extract a part, etc., and then expose the insulation and the white Arrange color samples (JIS Z8102 “object color name”, etc.) and use a photography device such as a digital camera to adjust the white balance while adjusting the white balance so that the white color sample is reflected in the correct white color. Correct and take the picture.

  To adjust the white balance, the preset white balance of the digital camera may be used, or a manual white balance that is manually set may be used. By adjusting the white balance, it is possible to accurately capture the hue of the insulator that constitutes the oil-filled electrical device without being affected by differences in lighting or weather.

  When the insulator to be imaged is present in a narrow part, the image may be captured using a photographic equipment such as an endoscope fiberscope.

  The image photographed in this way is compared with the color sample described above, and the color sample whose hue matches or is closest is specified. Next, the average degree of polymerization corresponding to the color sample specified using the color difference criterion described above is obtained. Thus, if the average degree of polymerization of an insulator is calculated | required, it will become possible to diagnose the deterioration degree of an oil-filled electrical equipment.

  Next, a specific example of the deterioration diagnosis method according to the third embodiment of the oil-filled electrical apparatus that is a deterioration diagnosis target will be described. First, drain the insulation oil from the oil-filled electrical equipment that is subject to deterioration diagnosis, lift the electrical equipment body, extract a part, etc., expose the insulation, and shoot new insulation paper under the same conditions with a digital camera, etc. Shoot using equipment.

  The color difference between the hues of the insulation paper of the oil-filled electrical device and the new insulation paper is compared with the photographed image, and the insulation that applies to the color difference is shown in the scatter diagram showing the correlation between the average degree of polymerization and the hue created according to claim 2. By determining the average degree of polymerization of the product, it is possible to determine the degree of deterioration of the oil-filled electrical device.

  As described above, according to the degradation diagnosis method of the present invention, it is not necessary to bring the insulating oil extracted from the oil-filled electrical equipment back to the analysis chamber and perform the degradation diagnosis using a gas chromatograph or a liquid chromatograph as in the past. In addition, deterioration diagnosis can be performed quickly at the site where oil-filled electrical equipment is installed.

  In addition, the deterioration diagnosis needs only to have a container made of insulating paper and insulating oil, a preparation device composed of a lid that seals the inside of the container, and a thermostatic chamber that heats the container. The configuration is simple and can be configured at low cost.

  Furthermore, since the inside of the production device A of the present invention can be set to substantially the same environment as the case of the oil-filled electrical device that is the subject of deterioration diagnosis, the color sample produced in the production device A is the oil-filled electrical device that is the subject of degradation diagnosis. In this case, the hue and color difference approximate to those of insulating paper deteriorated, and the accuracy of deterioration diagnosis can be increased.

DESCRIPTION OF SYMBOLS 1 Storage container 2 Insulation paper 3 Insulation oil 4, 7 Through-hole 5 Flange part 6 Lid 8 Packing 9 Bolt 10 Plate washer 11 Spring washer 12 Nut 13 Vent hole 14 Vent pipe 15 Valve A Color sampler

Claims (5)

  Insulating oil and insulating paper are hermetically housed in a container that simulates the deterioration prevention specifications of the oil-filled electrical equipment, the container is heated, and a portion of it is collected from the insulating paper every time the scheduled heating time elapses. Then, the average degree of polymerization is measured using a part of the collected insulating paper, and the remainder of the collected insulating paper is used as a color sample in the measurement value of the average degree of polymerization. Manufacturing method.   Insulating oil and insulating paper are hermetically housed in a container that simulates the deterioration prevention specifications of the oil-filled electrical equipment, the container is heated, and a portion of it is collected from the insulating paper every time the scheduled heating time elapses. Then, the average degree of polymerization is measured from a part of the collected insulating paper, and the remainder of the collected insulating paper is used as a color sample in the measured value of the average degree of polymerization, and the correlation between the hue of the color sample and the average degree of polymerization is measured. A method for producing a color difference reference, wherein the relationship is a color difference reference.   Insulators that make up the oil-filled electrical equipment after the insulation oil is drained from the oil-filled electrical equipment that is subject to deterioration diagnosis, or the electrical equipment body is lifted, or a part of it is extracted to expose the insulation to the atmosphere A method of diagnosing deterioration of oil-filled electrical equipment by measuring the color difference between the oil soaking conditions of the color samples and estimating the average degree of polymerization.   Insulators that make up the oil-filled electrical equipment after the insulation oil is drained from the oil-filled electrical equipment that is subject to deterioration diagnosis, or the electrical equipment body is lifted, or a part of it is extracted to expose the insulation to the atmosphere By adjusting the white balance with the white color standard and taking an image, comparing the captured image with the color sample, and using the color difference standard to determine the average degree of polymerization of the color sample with similar hue, A method for diagnosing deterioration of oil-filled electrical equipment using color difference criteria, characterized by diagnosing the degree of degradation of the electrical equipment.   Remove the insulation oil from the oil-filled electrical equipment that is subject to deterioration diagnosis, lift the electrical equipment body, or extract a part of the insulation to expose it to the atmosphere, and then immerse the new insulation paper in the insulation oil. The color difference is characterized by diagnosing the degree of deterioration of the oil-filled electrical device by comparing the color difference between the insulator constituting the oil-filled electrical device and the new insulating paper and the color difference standard. Degradation diagnosis method for oil-filled electrical equipment using standards.

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