JP2015165553A - Diagnostic method of oil-filled electric equipment, diagnostic device of oil-filled electric equipment and oil-filled electric equipment including the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a diagnostic method of an oil-filled electric equipment, a diagnostic device of oil-filled electric equipment and an oil-filled electric equipment including the same capable of diagnosing for internal abnormality of the oil-filled electric equipment by analyzing dissolved gas in insulation oil without sampling the insulation oil from the oil-filled electric equipment.SOLUTION: The diagnostic method of an airtight oil-filled electric equipment including a conservator 9 having an elastic bag body 15. The diagnostic method diagnoses for internal abnormality in the oil-filled electric equipment by analyzing gas in the elastic bag body.

Description

  The present invention relates to a diagnostic method for oil-filled electrical equipment, a diagnostic apparatus for oil-filled electrical equipment, and an oil-filled electrical equipment including the same.

  As one of methods for monitoring the state (degree of abnormality) of oil-filled electrical equipment such as a transformer, a method of analyzing gas in oil is known.

  When overheating or electric discharge occurs inside the oil-filled electrical equipment, a specific decomposition gas is generated depending on the temperature of the abnormal part, and most of it is dissolved in the insulating oil. In particular, in the case of a hermetically sealed transformer (for example, see Patent Document 1: Japanese Patent Laid-Open No. 2008-227268), the decomposed gas is in a state of being dissolved in insulating oil without escaping into the atmosphere, and this dissolved gas is analyzed. It is possible to estimate whether or not there is an internal abnormality and the situation.

Specifically, for example, insulating gas is collected from oil-filled electrical equipment, and dissolved gas extracted from sample oil (for example, C ₂ H _2, CH _4, C ₂ H generated when an internal abnormality of the oil-filled electrical equipment occurs) ₄ , flammable gases such as H ₂ , C ₃ H ₈ , C ₂ H ₆ ) are analyzed using a gas chromatograph, etc., and a method for judging abnormalities in oil-filled electrical equipment from these gas concentrations and gas aspects is known. It has been.

JP 2008-227268 A

  In order to analyze the gas dissolved in the oil (gas analysis in oil), it is necessary to collect the insulation oil of oil-filled electrical equipment for the above judgment. It is necessary to collect oil so as not to mix. Moreover, the operation which extracts the dissolved gas in the extract | collected insulating oil is also required. In addition, skilled skills are required for oil collection because it causes environmental problems if the insulating oil is spilled during oil collection. In addition, if the number of analyzes increases and the amount of insulation oil in oil-filled electrical equipment decreases, it becomes a problem in operation. It is necessary to confirm that the amount of oil is collected, and when the amount of oil collected reaches an amount that hinders operation, it is necessary to supplement the insulating oil.

  The present invention has been made in view of the above problems, and by analyzing the dissolved gas in the insulating oil without collecting the insulating oil from the oil-filled electric equipment, it is possible to determine whether there is an internal abnormality in the oil-filled electric equipment. An object of the present invention is to provide a method for diagnosing oil-filled electrical equipment, a diagnostic apparatus for oil-filled electrical equipment, and an oil-filled electrical equipment equipped with the same.

  The inventors have made use of the property that flammable gas in insulating oil generated when an internal abnormality occurs easily permeates through the elastic bag body, and without collecting insulating oil from oil-filled electrical equipment, By analyzing the gas in the bag, it was found that the dissolved gas in the insulating oil can be easily analyzed, and the present invention has been achieved.

  That is, the present invention relates to a method for diagnosing a sealed oil-filled electrical device including a conservator having an elastic bag body, and by analyzing gas in the elastic bag body, an internal abnormality of the oil-filled electrical device is disclosed. It is a diagnostic method characterized by diagnosing the presence or absence.

  The present invention also relates to a diagnostic apparatus for a sealed oil-filled electrical device including a conservator having an elastic bag body, the diagnostic apparatus including a sampling mechanism for sampling gas in the elastic bag body. Furthermore, the present invention provides a diagnostic apparatus for a sealed oil-filled electrical device including a conservator having an elastic bag body, the diagnostic apparatus including an analysis device for analyzing gas in the elastic bag body. Related.

  According to the present invention, since the dissolved gas in the insulating oil can be analyzed without collecting the insulating oil from the oil-filled electrical device, it is possible to easily diagnose whether there is an abnormality in the oil-filled electrical device. Moreover, since there is no reduction in the amount of insulating oil due to oil collection, it is possible to diagnose oil-filled electrical equipment economically.

It is a schematic diagram for demonstrating the diagnostic apparatus of the oil-filled electrical apparatus of Embodiment 1. It is a schematic diagram for demonstrating the diagnostic apparatus of the oil-filled electrical apparatus of Embodiment 2. It is a schematic diagram for demonstrating the diagnostic apparatus of the oil-filled electrical apparatus of Embodiment 3. It is a cross-sectional schematic diagram for demonstrating the oil-filled electrical apparatus of Embodiment 4. It is a cross-sectional schematic diagram for demonstrating an example of a structure of the oil-filled electrical equipment used as the diagnostic object of this invention.

  Embodiments of the present invention will be described below with reference to the drawings. In the drawings of the present invention, the same reference numerals represent the same or corresponding parts. In addition, dimensional relationships such as length, width, thickness, and depth are changed as appropriate for clarity and simplification of the drawings, and do not represent actual dimensional relationships.

(Embodiment 1)
With reference to FIG. 5, the diagnostic method and diagnostic apparatus of this embodiment are applied to a sealed oil-filled electrical device. The oil-filled electrical device to be diagnosed is provided with a conservator (oil deterioration prevention device) 9 for the purpose of preventing deterioration of the insulating oil due to oxidation or moisture absorption.

  The conservator 9 includes a mechanism for buffering the volume change of the insulating oil 16 by the elastic bag body 15 while sealing the insulating oil in the sealed chamber so that the insulating oil and air (outside air) do not directly contact each other. That is, the inside of the elastic bag body 15 communicates with the outside air via the hygroscopic respirator 18 and the hygroscopic respirator connecting pipe 14, and by inhaling or discharging the external air according to the volume change of the insulating oil 16, The volume change of the insulating oil 16 can be buffered without bringing the insulating oil and air into contact with each other.

  Examples of the material of the elastic bag body 15 include rubber, and oil-resistant rubber is preferable. Examples of the oil-resistant rubber include nitrile rubber (copolymer of butadiene and acrylonitrile rubber) and silicone rubber, and nitrile rubber is often used as the material for the elastic bag used for the conservator. Thus, the main constituent elements of the material of the elastic bag body 15 are C (carbon) and H (hydrogen).

Combustible gas (C ₂ H _2, CH _4, C ₂ H ₄ , H ₂ , C ₃ H ₈ , C ₂ H _6, etc.) generated when an oil-filled electrical device is abnormal is also composed of C and H. It is a component. For this reason, these gases have a large property (permeability) to permeate nitrile rubber. Therefore, the combustible gas generated in the oil-filled electrical device main body 5 and dissolved in the insulating oil 16 passes through the elastic bag body 15 of the conservator 9 and diffuses into the air in the elastic bag body 15. Easy to be.

  The oil-filled electrical device main body 5 is connected to the conservator 9 via the connection pipe 10, and the insulating oil 16 in the oil-filled electrical device main body 5 flows to the conservator 9 via the connection pipe 10. The conservator 9 is connected to the upper side of the pressure release pipe 4 having the air vent 2 and the pressure release plate 3 through the connection pipe 6. The conservator 9 has an air vent flange 7, a vacuum deaeration valve 11, a vacuum pressure equalizing valve 12, and a vacuum pressure equalizing pipe 13 at the top, and an oil discharge valve 17 at the bottom. Have.

  FIG. 1 is a schematic diagram for explaining a diagnostic apparatus (a structure for collecting combustible gas from an elastic bag of a conservator) according to the first embodiment. In the diagnostic device according to the present embodiment, the gas sampling tubule 20 is inserted into the elastic bag 15 to collect gas.

  Referring to FIG. 1, the elastic bag body 15 of the conservator 9 has a hole in the attachment portion of the connecting pipe 14 that connects the elastic bag body 15 and the hygroscopic respirator 18, and the thin tube 20 is inserted into this hole. It has a structure that can be inserted. By opening the cock 19 provided in the upper part of the thin tube 20, the gas in the elastic bag 15 can be sucked and collected. As described above, the diagnostic device according to the present embodiment includes the collection mechanism for collecting the gas in the elastic bag body 15.

The gas to be analyzed is preferably a combustible gas. Examples of the combustible gas include saturated hydrocarbons such as CH ₄ , C ₂ H ₆ , and C ₃ H ₈ , unsaturated hydrocarbons such as C ₂ H ₂ , C ₂ H ₄ , and C ₃ H ₆ , H ₂ (hydrogen) may be mentioned. These gas components serve as indices for monitoring the state (degree of abnormality) of oil-filled electrical equipment such as a transformer. One of these gases may be analyzed, or a plurality of gases may be analyzed simultaneously or separately.

In order to collect a gas heavier than the air staying below the elastic bag body 15 (C ₃ H _8, C ₂ H _6, etc.), the lower end (front end) of the thin tube 20 is near the lower end in the elastic bag body 15. It is desirable to arrange in. Further, if a mechanism capable of moving the lower end of the narrow tube 20 up and down is provided, a gas that is lighter than air is collected and a gas that is heavier than the air staying under the elastic bag 15 (C ₃ H _8, C ₂ H _6, etc.) It is also possible to perform the sampling by one mechanism.

(Embodiment 2)
FIG. 2 is a schematic diagram for explaining the diagnostic apparatus according to the second embodiment. The diagnostic apparatus according to the present embodiment is different from the first embodiment in that the gas analyzer 22 is connected to one side (upper end) of the thin tube 20 via the connection pipe 21, but the other points are different from the first embodiment. It is the same.

  In this embodiment, since such an analyzer (gas analyzer 22) is provided, there is an advantage that gas analysis and abnormality determination can be performed at the sampling site.

  In addition, based on the analysis result obtained by such an analyzer, if it further comprises a determination function for determining the presence or absence of internal abnormality of the oil-filled electrical equipment, gas analysis and abnormality determination at the sampling site is easy and It becomes possible to carry out accurately.

(Embodiment 3)
FIG. 3 is a schematic diagram for explaining the diagnostic apparatus according to the third embodiment. In this embodiment, a thin rod 23 with a bag 24b containing an adsorbent 24a for collecting gas is inserted into the elastic bag 15, and the gas in the elastic bag 15 is adsorbed to the adsorbent 24a and collected. However, the other points are the same as in the first embodiment.

  Referring to FIG. 3, a thin rod 23 with an adsorbent (a thin rod in which the adsorbent 24a is housed in a cloth or wire mesh bag 24b) is inserted into the elastic bag 15 of the conservator 9, and the adsorbent 24a is inserted. Adsorb the desired gas. The structure is such that the adsorbent can be removed, and the adsorbed gas is analyzed.

  According to the diagnostic device having the configuration as in the first to third embodiments, and the oil-filled electrical device including the diagnostic device, the gas in the elastic bag body without collecting the insulating oil from the oil-filled electrical device. The presence or absence of an internal abnormality of the oil-filled electrical device can be determined by collecting and analyzing the gas or directly analyzing the gas in the elastic bag.

(Embodiment 4)
In this embodiment, an example of the oil-filled electrical device of the present invention will be described. The oil-filled electrical device of this embodiment is characterized by having a circulation device (circulation structure) for circulating insulating oil in the conservator and in the oil-filled electrical device body. FIG. 4 is a schematic diagram for explaining the oil-filled electrical apparatus according to the present embodiment.

  Referring to FIG. 4, the oil-filled electrical device according to the present embodiment includes an oil-filled electrical device main body 5, a conservator 9 having an elastic bag 15, and a diagnostic device as disclosed in the first to third embodiments. With. In addition, since the structure of the diagnostic apparatus is the same as that of the said Embodiment 1-3, in FIG. 4, the diagnostic apparatus is abbreviate | omitted for simplification.

  The oil-filled electrical device main body 5 has a first insulating oil storage portion 161 in which insulating oil is stored. Further, the conservator 9 has a second insulating oil reservoir 162 in which insulating oil is stored around the elastic bag body 15. The 1st insulating oil storage part 161 and the 2nd insulating oil storage part 162 are connected in two places via connection pipe 10a, 10b.

  The insulating oil is fed from the first insulating oil reservoir 161 into the second insulating oil reservoir 162 by the oil feed pump 31 (circulator) provided in the middle of the connecting pipe 10a. Thereby, insulating oil circulates in the direction of the arrow in a figure in the 1st insulating oil storage part 161 and the 2nd insulating oil storage part 162. FIG.

  By circulating the insulating oil in the first insulating oil reservoir 161 and the second insulating oil reservoir 162, the gas generated in the first insulating oil reservoir 161 and dissolved in the insulating oil is elastic. It becomes easy to permeate into the bag body 15. Thereby, the analysis sensitivity of the gas to be analyzed is improved. Moreover, the insulating oil in the conservator 9 and the insulating oil in the oil-filled electrical device main body 5 can be homogenized. Thereby, the state of the insulating oil in the oil-filled electrical device main body 5 can be diagnosed with higher accuracy.

  In addition, the oil-filled electrical apparatus according to the present embodiment includes a cooler 51. The internal pipe 51 a of the cooler 51 communicates with the first insulating oil storage unit 161 through connection pipes 52 and 53. The insulating oil in the internal pipe 51 a is fed into the first insulating oil reservoir 161 by an oil feed pump 32 (circulation device) provided in the middle of the connecting pipe 53. Thereby, insulating oil circulates in the direction of the arrow in a figure in the internal piping 51a and the 1st insulating oil storage part 161. FIG.

  Here, the connecting pipe 10b connected to the second insulating oil reservoir 162 of the conservator 9 is stored in the second insulating oil by the negative pressure of the insulating oil flowing into the cooler 51 via the connecting pipe 52. In the position where the insulating oil in the part 162 is sucked, it is connected to the first insulating oil storage part 161. Thereby, the circulation of the insulating oil in the 1st insulating oil storage part 161 and the 2nd insulating oil storage part 162 is accelerated | stimulated using the drive force of the oil feed pump 32 of the cooler 51. FIG.

  In oil-filled electrical equipment, insulating oil usually has not only an insulating function but also a role of cooling the equipment, and therefore a circulation device is provided for circulating the insulating oil in the cooler. Therefore, if the driving force of the oil feed pump 32 of the cooler 51 is utilized by such an arrangement of the connecting pipe 10b, the diagnostic accuracy can be improved without providing a separate pump such as the oil feed pump 31. . In addition, the diagnostic accuracy can be further improved by using the oil feed pump 31 together with the driving force of the oil feed pump 32 of the cooler 51.

  It should be thought that embodiment disclosed this time is an illustration and restrictive at no points. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  DESCRIPTION OF SYMBOLS 1 Gas detection apparatus, 2 Air vent plug, 3 Pressure release plate, 4 Pressure release pipe, 5 Oil-filled electrical equipment main body, 6 Connection pipe, 7 Air vent flange, 8 Oil level gauge, 9 Conservator, 10, 10a, 10b Connection pipe, 11 Vacuum deaeration valve, 12 Vacuum pressure equalizing valve, 13 Vacuum pressure equalizing pipe, 14 Connecting pipe, 15 Elastic bag (rubber bag), 16 Insulating oil, 161 First insulating oil reservoir, 162 Second insulating oil reservoir, 17 Exhaust valve, 18 Hygroscopic respirator, 19 Cock, 20 Narrow tube, 21 Connection tube, 22 Gas analyzer, 23 Narrow rod, 24a Adsorbent, 24b Container, 31, 32 Oil feed pump, 51 Cooler, 51a Inside Piping, 52, 53 Connecting pipe.

Claims (7)

A method for diagnosing a sealed oil-filled electrical device including a conservator having an elastic bag,
A method for diagnosing an oil-filled electrical device, wherein the presence or absence of an internal abnormality of the oil-filled electrical device is diagnosed by analyzing a gas in the elastic bag.   The method for diagnosing an oil-filled electrical device according to claim 1, wherein the gas in the elastic bag is collected and analyzed when analyzing the gas in the elastic bag. A sealed oil-filled electrical device diagnostic apparatus including a conservator having an elastic bag,
A diagnostic apparatus for oil-filled electrical equipment, comprising a collection mechanism for collecting gas in the elastic bag. A sealed oil-filled electrical device diagnostic apparatus including a conservator having an elastic bag,
A diagnostic apparatus for oil-filled electrical equipment, comprising an analyzer for analyzing gas in the elastic bag.   The diagnostic apparatus for an oil-filled electrical device according to claim 4, comprising a determination function for determining the presence or absence of an internal abnormality of the oil-filled electrical device based on an analysis result obtained by the analysis device. An oil-filled electrical device main body, a conservator having an elastic bag, and the diagnostic device according to any one of claims 3 to 5,
The oil-filled electrical device main body has a first insulating oil storage section in which insulating oil is stored,
The conservator has a second insulating oil storage part in which insulating oil is stored around the elastic bag body,
An oil-filled electrical device in which the first insulating oil reservoir and the second insulating oil reservoir are in communication.   Furthermore, the oil-filled electrical apparatus of Claim 6 provided with the circulation apparatus for circulating insulating oil in the said 1st insulating oil storage part and the said 2nd insulating oil storage part.

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