JP6193661B2 - Insulation deterioration diagnosis device for insulation material and diagnosis method thereof - Google Patents

Description

  Embodiments described herein relate generally to an insulation deterioration diagnosis device for an insulation material used for electric power equipment, and a diagnosis method thereof.

  2. Description of the Related Art Conventionally, in power facilities, an insulator formed of an insulating material such as an epoxy resin or a polyester resin has been widely used, and high functionality and downsizing are achieved. Since such power equipment continues stable operation for a long period of time, an insulation deterioration diagnosis of an insulator that supports and fixes the main circuit member is performed.

  This type of insulation deterioration diagnosis includes an estimation means and a diagnosis means. The estimation means estimates the actually measured insulation resistance value to the insulation resistance value under a bad environment, and the insulation resistance value is estimated by the T method (Taguchi method) of multivariate analysis. The diagnosis means obtains an effective period during which the insulator can be used from the estimated insulation resistance value, and prevents an insulation accident in advance (for example, see Patent Document 1).

  Here, the measurement of the insulation resistance is an arbitrary portion of the insulator, and in general, the top surface of the insulator is selected so that the measurement is easy and dust is easily deposited. In addition, there are some cases where reliability is improved by measuring at a plurality of locations, but the location is not yet determined. It is assumed that the insulator is subjected to various stresses such as mechanical and electrical depending on the state of use, and the deterioration state is also different. For this reason, the thing which can grasp | ascertain the degradation condition of the insulator to which various stresses are added was desired.

JP 2012-141146 A

  The problem to be solved by the present invention is that insulation of an insulating material that can reliably diagnose insulation deterioration of an insulator that is assumed to be subjected to various stresses such as mechanical and electrical and that the deterioration situation is also different. It is an object of the present invention to provide a deterioration diagnosis apparatus and a diagnosis method thereof.

In order to solve the above-described problems, the insulation deterioration diagnosis device for an insulating material according to the embodiment measures from a mechanically deteriorated part, an electrically deteriorated part, a thermally deteriorated part, and an environmentally deteriorated part of an insulating barrier used for a vacuum circuit breaker. An input unit for inputting the measured insulation resistance value, an estimation unit for estimating the measured insulation resistance value to an estimated insulation resistance value under a predetermined environment, and comparing a plurality of the estimated insulation resistance values to obtain a minimum insulation resistance value. comprising a comparison extracting unit that extracts, in comparison with the minimum insulation resistance deterioration characteristic curve that has been previously obtained, and a diagnosis unit for performing insulation diagnosis by calculating the time to below the threshold, the mechanical degradation sites Is an upper surface of the insulation barrier that fixes the upper conductor, the electrical deterioration portion is an interphase portion of the insulation barrier that fixes the upper conductor or the lower conductor, and the thermal deterioration portion is a movable shaft of the vacuum valve. Is connected Is said isolation barrier portion for fixing the lower conductor, the environmental degradation sites, wherein said insulating barrier top, and a side.

The block diagram which shows the structure of the insulation deterioration diagnostic apparatus of the insulating material which concerns on the Example of this invention. The flowchart explaining operation | movement of the insulation deterioration diagnostic apparatus of the insulating material which concerns on the Example of this invention. The perspective view which shows the measurement site | part of the insulation deterioration diagnostic apparatus of the insulating material which concerns on the Example of this invention. The characteristic view explaining the insulation diagnosis of the insulation deterioration diagnosis apparatus of the insulating material which concerns on the Example of this invention.

  Embodiments of the present invention will be described below with reference to the drawings.

  An insulation deterioration diagnosis apparatus for an insulation material according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a block diagram showing a configuration of an insulation deterioration diagnosis apparatus for an insulating material according to an embodiment of the present invention according to Embodiment 1 of the present invention, and FIG. 2 is an insulation deterioration diagnosis for an insulation material according to an embodiment of the present invention. FIG. 3 is a perspective view showing a measurement site of an insulation material insulation deterioration diagnosis apparatus according to an embodiment of the present invention, and FIG. 4 is an insulation material insulation according to an embodiment of the present invention. It is a characteristic view explaining the insulation diagnosis of a deterioration diagnostic apparatus.

  As shown in FIG. 1, the insulation deterioration diagnosis device for an insulating material has an input unit 1 for inputting an insulation resistance value (measured insulation resistance value) measured from a plurality of locations on the surface of the insulator, an insulation resistance value under a predetermined environment ( (Estimated insulation resistance value) estimation unit 2 for comparing, estimated insulation resistance values at a plurality of locations are compared, comparison extraction unit 3 for extracting the measurement point and the insulation resistance value (minimum insulation resistance value) that has changed most and decreased most, The diagnosis unit 4 is configured to calculate the remaining life from the extracted insulation resistance value that has been reduced most.

  Next, the insulation deterioration diagnosis will be described with reference to FIGS.

  As shown in FIG. 2, the measurement location includes a mechanically deteriorated part (s1) to which excessive mechanical stress is applied, an electrically deteriorated part (s2) to which excessive electrical stress is applied, and a thermal stress is greatly applied. It is a thermal degradation site (s3), an environmental degradation site (s4) that is easily exposed to harmful gases and that dust is likely to accumulate.

  These specific measurement points will be described by taking a vacuum circuit breaker as an example. As shown in FIG. 3, the vacuum circuit breaker is provided with a vacuum valve 6 as indicated by a dotted line on an insulating barrier 5 made of an unsaturated polyester resin in which three phases are formed in a U shape. An upper conductor 7 and a lower conductor 8 are fixed above and below the vacuum valve 6. An operating mechanism (not shown) for opening and closing the vacuum valve 6 is provided below the lower conductor 8.

  The measurement location 10 is a portion for fixing the upper conductor 7 on the upper surface of the insulating barrier 5, and becomes a mechanical deterioration portion s 1 to which repeated mechanical shocks are most frequently applied when the vacuum valve 6 is opened and closed. The measurement location 11 is a portion in the vicinity of the upper conductor 7 that provides phase-to-phase insulation on the upper surface of the insulation barrier 5 and is an electrically deteriorated portion s2 in which the electric field strength is highest. It may be an interphase portion of the lower conductor 8. The measurement location 12 is a connection location where the movable shaft of the vacuum valve 6 is connected to the lower conductor 8, and the temperature rises greatly and becomes a thermal degradation site s3. The measurement location 13 is the upper surface of the insulating barrier 5 where dust is likely to accumulate, and the measurement location 14 is a portion that is easily exposed to harmful gases, ultraviolet rays, and the like on the side surface of the insulation barrier 5, and the environmental degradation site s4. Become. As for the deteriorated portion, a representative portion that is likely to cause deterioration is measured to prevent measurement omission.

The insulation resistance (measured insulation resistance value) measured from such a plurality of locations varies depending on the temperature and humidity at the time of measurement. For this reason, the insulation resistance value (estimated insulation resistance value) in a bad environment such as a temperature of 40 ° C. and a humidity of 95% RH is estimated from the temperature / humidity characteristics of new and deteriorated products obtained in advance (s5). ). A new product is hardly affected by temperature and humidity, but a deteriorated product is greatly affected in proportion to the degree of deterioration. Next, a measurement location that is the largest change from the estimated insulation resistance value and has the lowest value (minimum insulation resistance value) is extracted (s6). This is compared with the deterioration characteristic curve obtained in advance, the time until it falls below the threshold is obtained, and the remaining life is calculated (s7). The remaining life is the remaining time that can be soundly operated. The threshold is, for example, 10 ⁷ Ω. At a temperature of 40 ° C. and a humidity of 95% RH. cm is chosen.

  Here, as shown in FIG. 4, the deterioration characteristic curve can be approximated by a straight line to a log-log graph, but may not be approximated depending on the deteriorated part as the deterioration progresses. In the mechanically deteriorated portion, when a micro crack is caused by repeated fatigue, the A characteristic is rapidly reduced from time t0. In addition, in the electrically deteriorated portion, when tracking occurs, the A characteristic decreases rapidly from time t0 as in the case of the mechanically deteriorated portion. In the thermally deteriorated part and the environmentally deteriorated part, the B characteristic is uniformly accumulated and deteriorated. For this reason, in the measurement after time t0, as described above, the time t1 on the short time side below the threshold is obtained. On the other hand, in the measurement before time t0, since all the deteriorated parts have the same insulation resistance value, time t1 or time t2 is obtained. However, comparison with the measurement location is performed, and clearly the A characteristic is used at the mechanical and electrical degradation sites, and the B characteristic is used at the thermal and environmental degradation sites. In the combined deterioration, the A characteristic is used in consideration of the safety side.

  In addition, the deterioration characteristic curves of the A characteristic and the B characteristic can be obtained from data accelerated and deteriorated in the laboratory, including the locally collected products. In particular, the data of locally collected products faithfully reflects various aspects of deterioration, and can greatly improve reliability.

  In the above description, the unsaturated polyester resin is used as the insulating material. However, the insulating barrier and support cast with epoxy resin, and the insulator used for power equipment such as the insulating rod processed with the glass laminated epoxy plate. Can be applied to.

  In addition, since insulation deterioration is largely caused by discoloration, insulation diagnosis can be performed with high accuracy by measuring surface roughness, glossiness, and color tone in addition to measurement of insulation resistance. Furthermore, if the same part is measured in each of the three phases, the average value of the deteriorated parts is calculated, and the remaining life is obtained, the accuracy of the insulation diagnosis can be improved.

  Here, the insulation resistance value, surface roughness, glossiness, and color tone are referred to as insulation diagnosis values. These also estimate the estimated value from the actually measured value, and the minimum value is extracted.

  According to the insulation deterioration diagnosis device for an insulating material of the above embodiment, the insulation resistance is measured from a plurality of locations of a mechanical deterioration portion, an electrical deterioration portion, a thermal deterioration portion, and an environmental deterioration portion in the insulation barrier 5, Since the deteriorated portion showing the lowest value is extracted from the inside and the remaining life is calculated from the deterioration characteristic curve, it is possible to prevent measurement omission and perform insulation deterioration diagnosis with high accuracy.

  According to the embodiment as described above, since the insulation resistance is actually measured from a plurality of locations and the minimum value is extracted, the accuracy of the insulation deterioration diagnosis can be remarkably improved.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 Input part 2 Estimation part 3 Comparison extraction part 4 Diagnosis part 5 Insulation barrier 6 Vacuum valve 7 Upper conductor 8 Lower conductor 10, 11, 12, 13, 14 Measurement location

Claims (2)

An input unit for inputting a measured insulation resistance value measured from a mechanically deteriorated part, an electrically deteriorated part, a thermally deteriorated part, and an environmentally deteriorated part of an insulation barrier used in a vacuum circuit breaker ;
An estimation unit that estimates the measured insulation resistance value to an estimated insulation resistance value under a predetermined environment ;
A comparison extraction unit that extracts a minimum insulation resistance value by comparing a plurality of the estimated insulation resistance values ;
Comparing with the deterioration characteristic curve obtained in advance the minimum insulation resistance value, comprising a diagnostic unit for performing insulation diagnosis by calculating the time until it falls below the threshold ,
The mechanically deteriorated portion is the upper surface of the insulating barrier that fixes the upper conductor,
The electrical degradation site is an interphase portion of the insulation barrier that fixes the upper conductor or the lower conductor,
The thermally deteriorated portion is the insulating barrier portion that fixes the lower conductor to which the movable shaft of the vacuum valve is connected,
Insulating deterioration diagnosis apparatus for insulating material, wherein the environmentally deteriorated portion is an upper surface and a side surface of the insulating barrier . Measure the insulation resistance from the mechanical, electrical, thermal, and environmental degradation sites of the insulation barrier used in vacuum circuit breakers.
After estimating these insulation resistances to insulation resistance values at a temperature of 40 ° C. and a humidity of 95%,
Compare the estimated insulation resistance value and extract the lowest value,
In contrast to the deterioration characteristic curve obtained in advance, the minimum value is an insulation diagnosis method for an insulating material that calculates the time until the threshold value is exceeded,
The mechanically deteriorated portion is the upper surface of the insulating barrier that fixes the upper conductor,
The electrical degradation site is an interphase portion of the insulation barrier that fixes the upper conductor or the lower conductor,
The thermally deteriorated portion is the insulating barrier portion that fixes the lower conductor to which the movable shaft of the vacuum valve is connected,
The insulation diagnostic method for an insulating material, wherein the environmentally deteriorated portion is an upper surface and a side surface of the insulating barrier.

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