JP6037611B2 - Diagnosis method for remaining insulation life of power distribution equipment - Google Patents

Description

  The present invention relates to a method for diagnosing a remaining life of an insulator provided in a power receiving / distributing device, and more particularly to a method for diagnosing a remaining life due to a decrease in resistance of an insulator provided in an operating power receiving / distributing device. .

  The power distribution facility is a facility responsible for supplying electrical energy to factories and buildings. Power distribution facilities are required to operate with reliability and stability. If the insulation used in the power distribution equipment deteriorates due to the long-term use of the power distribution equipment, and an electrical trouble occurs as a result, the production equipment or building, such as loss in production or repair of the equipment, will be The effect will increase. For this reason, the technique for diagnosing degradation of the insulator used for power distribution equipment with high accuracy is desired.

  In general, the deterioration process of the insulator in the power distribution facility is considered as follows. (1) The resistance of the insulator surface decreases. (2) Due to Joule heat due to leakage current, a local dry zone is formed in the insulator. (3) Scintillation discharge is generated by voltage concentration on the dry zone. (4) Occurrence of dielectric breakdown due to carbonization of organic matter (formation of carbonized conductive paths) by discharge.

  Conventionally, as a method for diagnosing deterioration of an insulator, a method of measuring an insulation resistance or a method of measuring a partial discharge has been mainly performed. However, measured values of insulation resistance or measured values of partial discharge can vary greatly depending on humidity. Therefore, it cannot be said that the diagnostic accuracy is sufficient. In order to prevent electrical troubles in advance and to reduce maintenance costs by optimizing the maintenance cycle, it is important to diagnose the remaining insulation life in consideration of humidity conditions.

  For this reason, Patent Document 1 and Patent Document 2 describe a method for evaluating the deterioration degree of an insulator before an electrical abnormality occurs in consideration of humidity conditions. In these methods, an electrode is attached to an insulator, leakage current is measured, and the leakage current of the insulator is monitored, thereby diagnosing deterioration of the insulator included in the power receiving and distributing device.

  Among them, in the insulation deterioration detection method described in Patent Document 1, a large number of independent center electrodes on the insulating plate and outer peripheral electrodes surrounding the periphery thereof with a minute interval are arranged in a matrix, and the center electrodes and The degree of deterioration is evaluated by applying a voltage between the outer peripheral electrodes and measuring the resistance value.

  Patent Document 2 discloses a method for estimating the remaining insulation life as follows. That is, an insulation diagnostic sensor is attached to the power distribution facility. This sensor is made of a material equivalent to a solid insulating material used for a main circuit portion constituting the above power receiving and distributing equipment. The sensor has a degrading part that has been intentionally deteriorated and an undegraded part that has not been deteriorated, and the deteriorated part and the non-deteriorating part are provided with comb-shaped electrodes for measuring the surface electrical resistivity. Changes in the surface electrical resistivity of both parts are measured, and the remaining life of the power receiving and distributing equipment is calculated based on the reference curve representing the time dependence of the surface electrical resistivity and the change in the surface electrical resistivity.

JP-A-6-207918 JP 2002-372561 A

  The deterioration of the insulator at the site where the power distribution equipment is actually installed is affected by NOx (nitrogen oxide), SOx (sulfur oxide), dust or contaminants in the atmosphere. For this reason, the actual deterioration of the insulator is caused by the fact that ionic compounds with deliquescence that are generated or attached to the surface of the insulator absorb moisture in the atmosphere while various deterioration modes change in a complex manner. The surface resistivity decreases.

  In the insulation degradation detection method described in Patent Document 1, in order to make the humidity condition at the time of measurement constant, the resistance is measured by wetting the surface of the insulator with electronic cooling or a humidifier. As described above, there are various ionic compounds on the surface of the insulator, but when the surface of the insulator is wetted, compounds that do not have deliquescence dissolve in water and contribute to electrical conduction. In contrast, there is a problem that the deterioration of the insulator cannot be accurately detected.

  In the method for diagnosing the remaining insulation life described in Patent Document 2, the sensor is collected after a certain period of time on the power receiving and distributing device, and the surface resistivity of the sensor is measured in an environmental laboratory or the like set to a predetermined humidity. There must be. For this reason, according to the method of Patent Document 2, there is a problem that the remaining life diagnosis cannot be performed in real time. In addition, the deterioration of the insulator is detected based on the fixed correlation created by the accelerated deterioration test of the sensor sample in spite of the change of the deterioration mode at the site where the power distribution device is used. For this reason, the change in the deterioration mode at the site is not reflected in the correlation, and there is a problem that the deterioration of the insulator cannot be detected with high accuracy.

  The present invention has been made to solve the above-described problems, and an object thereof is to provide a remaining life diagnosis method and system capable of accurately diagnosing the remaining life of an insulator of a power receiving and distributing device in real time. To do.

The remaining life diagnosis method of the power receiving and distributing device of the present invention is a remaining life diagnostic method for determining the remaining life of the power receiving and distributing device including an insulator,
A sensor installation step in which a sensor insulator made of the same or equivalent material as that of the insulator is provided in advance in the power receiving and distributing device,
A measurement step of sequentially measuring the amount of two or more types of ions on the surface of the sensor insulator;
An analysis step for multivariate analysis of the amount of the two or more types of ions measured in the measurement step;
For the sensor insulator, a first correlation which is a correlation between the result of multivariate analysis of the amount of the two or more types of ions and the surface resistivity is obtained in advance, and based on the first correlation From the result of multivariate analysis obtained in the analysis step, a surface resistivity calculation step for calculating the surface resistivity of the sensor insulator;
A second correlation update step of sequentially updating a second correlation, which is a correlation between the surface resistivity of the sensor insulator and the service life, using the surface resistivity calculated in the surface resistivity calculation step. When,
A remaining life calculating step for obtaining a remaining life of the power receiving / distributing device based on the second correlation updated in the second correlation updating step.

  According to the method for diagnosing the remaining life of a power receiving / distributing device of the present invention, the remaining life of an insulator provided in the power receiving / distributing device can be accurately diagnosed in real time, and an electrical trouble due to deterioration of the insulator can be prevented in advance. Can do.

It is the figure which showed the general view of the circuit breaker used for a power receiving / distributing apparatus. It is a general-view figure of a mold frame. It is the schematic which showed an example of the electrical room by which the some power receiving / distributing apparatus was arrange | positioned. 3 is a flowchart for explaining a remaining life diagnosis method for a power receiving and distributing device according to the first embodiment. FIG. 3 is a schematic diagram showing a surface of a sensor insulator in the first embodiment. It is a schematic diagram which shows the 1st correlation of the result of having performed the multivariate analysis of each ion amount, and the measured value of the surface resistivity in 50% of humidity of an insulator. It is a schematic diagram for demonstrating the update method of a 2nd correlation. It is the figure which plotted the surface resistivity of the sensor insulator for every years of use. It is a schematic diagram for demonstrating a 2nd correlation. (A), (b) is a schematic diagram for demonstrating an example of the deterioration mechanism of the insulator by NOx and SOx in air | atmosphere.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The same or corresponding parts are denoted by the same reference numerals, and the description thereof will not be repeated.

<Embodiment 1>
The remaining life diagnosis method for a power receiving / distributing device according to Embodiment 1 is a remaining life diagnosis method for obtaining the remaining life of a power receiving / distributing device including an insulator. The power receiving / distributing device includes, for example, main circuit components such as a circuit breaker, a disconnector, a busbar / conductor, and a measuring device. An example of the configuration of the power receiving / distributing device will be described below, but the present invention is not limited to this configuration.

  FIG. 1 is a diagram showing an overview of a circuit breaker used in a power receiving and distributing device. Referring to FIG. 1, blocking portions 101, 102, and 103 are installed corresponding to the three AC phases, respectively. Each of the blocking portions 101, 102, 103 is supported by a mold frame 104. FIG. 2 is an overview of the mold frame. Referring to FIGS. 1 and 2, the mold frame 104 is formed of, for example, an unsaturated polyester insulator. FIG. 2 shows the dimensions of the mold frame 104, but these dimensions are merely examples and do not limit the present invention.

  FIG. 3 is a schematic view showing an example of the electrical chamber 4 in which a plurality of power receiving and distributing devices 5 are arranged. As shown in FIG. 3, the power receiving / distributing device 5 and the sensor insulator 1 are installed in an electric chamber 4 provided with an opening that can exchange outside air and room air. In the opening, for example, there are at least one of a bus duct 6 that sucks outside air 9 into the electric chamber 4, a pit 7, a forced ventilation port 8 that exhausts indoor air 10 from the electric chamber 4, or a cable inlet (not shown). Applicable. Wind may be sent into these openings by an air conditioner. In the present embodiment, the opening is assumed to be the bus duct 6 and the pit 7. In the present embodiment, as shown in FIG. 3, the surface of the sensor insulator 1 is disposed so as to face the openings.

  In FIG. 3, the bus duct 6 is provided on the upper side of the electrical chamber 4, and the sensor insulator 1 is disposed on the upper surface of the power receiving and distributing device 5 in the vicinity of the bus duct 6. In this way, the surface of the sensor insulator 1 is arranged in the vicinity of the bus duct 6 so as to face the bus duct 6.

  On the other hand, the pit 7 is provided on the lower side of the electric chamber 4, and another sensor insulator 1 is disposed on the lower surface of the power receiving / distributing device 5 in the vicinity of the pit 7. As described above, the surface of the other sensor insulator 1 is disposed in the vicinity of the pit 7 so as to face downward and face the pit 7.

  For the power receiving / distributing device 5 arranged as described above, the remaining life diagnosis method for the power receiving / distributing device according to the present embodiment is used.

  Next, a method for diagnosing the remaining life of a power receiving / distributing device according to Embodiment 1 will be described. FIG. 4 is a flowchart for explaining a method for diagnosing the remaining life of power receiving and distributing equipment according to the present embodiment.

(Sensor installation step S0)
3 and 4, first, the sensor insulator 1 made of the same or equivalent material as the diagnosis target insulator provided in the power receiving / distributing device 5 is preliminarily stored in the power receiving / distributing device 5 in advance as described above. It is provided in the place of. The sensor insulator 1 is provided until the use of the power receiving / distributing device 5 is started, and the use of the power receiving / distributing device 5 is started.

  The insulator to be diagnosed is an insulator that is desired to diagnose insulation deterioration among insulators provided in the power receiving / distributing device, for example, an insulator that is severely deteriorated and important in the life of the power receiving / distributing device. An example of such an insulator is the mold frame described above.

  The insulator to be diagnosed may be specified in advance. Alternatively, the surface resistivity of each of the plurality of insulators included in the power receiving and distributing device may be obtained, and the insulator having the lowest surface resistivity may be determined as the insulator to be diagnosed. The number of insulators to be diagnosed may be plural.

  The sensor insulator includes an insulator and an ion selection electrode provided on the surface of the insulator. The insulator material included in the sensor insulator is the same as or equivalent to the insulator material of the power receiving / distributing device to be diagnosed. “Equivalent” means, for example, that the constituent elements of two insulators are the same as each other, and when the constituent ratios of the two insulators are compared, the difference in constituent ratios for the same elements is within ± 10%. It means that. Specific examples of the insulator material include unsaturated polyester resin, epoxy resin, and phenol resin. In general, the insulator is composed of a resin, a filler, a filler, an additive, and the like.

  The ion selection electrode provided on the surface of the sensor insulator is a surface resistance of an insulator such as a nitrate ion selection electrode, a sulfate ion selection electrode, a chloride ion selection electrode, an ammonium ion selection electrode, a sodium ion selection electrode, or a calcium ion selection electrode. It is a selective electrode for various ions that have a strong correlation with a decrease in the rate. Ions that have a strong correlation with the decrease in resistance of the insulator vary depending on the material of the insulator. When the insulator is an unsaturated polyester resin, the ions that have a strong correlation with the decrease in the resistance of the insulator are nitrate ions, sulfate ions, and chloride ions. A sensor insulator is configured by providing a selection electrode and a chloride ion selection electrode.

  The position where the sensor insulator 1 is installed is preferably as close as possible to the insulator to be diagnosed within a range that does not affect the function of the power receiving and distributing device. For example, the sensor insulator may have a function of supporting or shielding the conductor.

  FIG. 5 is a schematic view showing the surface of the sensor insulator. Referring to FIG. 5, the sensor insulator 1 includes an insulator 100 and a plurality of ion selection electrodes 2. In the present embodiment, the insulator 1 is made of an unsaturated polyester resin containing an additive such as calcium carbonate and glass fiber.

  The ion selective electrode 2 is disposed on the surface of the insulator 100. The ion selective electrode 2 may be made of any material as long as it exhibits conductivity, and more preferably can withstand corrosion caused by long-term use. In the present embodiment, the ion selective electrode 2 is made of SUS.

  A voltage of, for example, 200 V is applied to the ion selective electrode 2 and the leakage current between the ion selective electrodes 2 is measured with a leakage ammeter. Thereby, the surface resistivity of the insulator 100 is obtained. A wetting device 3 for wetting the insulator 100 such as an electronic cooling device or a steam humidifier is attached in the vicinity of the sensor insulator 1.

(Measurement step S1)
Next, the amount of two or more kinds of ions (for example, nitrate ion, sulfate ion and chloride ion) on the surface of the sensor insulator 1 is sequentially measured. In the present embodiment, the surface of the insulator 100 is wetted by the wetting device 3, and the amount of various ions dissolved in the water on the surface of the insulator 100 is measured by the various ion selective electrodes 2. These measurements are performed, for example, every month from the start of use of the sensor insulator 1 (at the start of use of the power receiving / distributing device).

(Analysis step S2)
Next, for an insulator of the same type as the insulator included in the sensor insulator , a correlation (first correlation) between each ion amount measured in step S1 and an actual measured value of the surface resistivity at 50% humidity of the insulator. Relationship) is obtained by multivariate analysis. Specifically, multivariate analysis is performed by, for example, Mahalanobis Taguchi system, neural network, multiple regression analysis, or the like.

(Surface resistivity calculation step S3)
Next, advance, on the basis of the first correlation had determined Meteor at analysis step S2, the amount of ions or al, calculates the surface resistivity B of the sensor insulator (see FIG. 6).

  In addition, the surface resistivity of the sensor insulator 1 shown here falls with the years of use due to a deterioration mechanism described later. Therefore, in general, the surface resistivity tends to gradually decrease every time the amount of ions is measured.

(Second correlation update step S4)
Next, in order to obtain the correlation (second correlation) between the surface resistivity of the sensor insulator calculated in the surface resistivity calculation step S3 and the time from the start of use of the sensor insulator, the usage time and the surface Resistivity data will be added sequentially. After the data is added, the second correlation is updated by recalculating the correlation between the surface resistivity and the age of use from the previous data.

  As the usage time, the service life of the sensor insulator 1 may be used, or the service life of the power receiving / distributing device 5 may be used. The sensor insulator 1 is made of the same or equivalent material as the insulator provided in the power receiving / distributing device 5 and is disposed at the same place as the power receiving / distributing device 5 and is used from the same time as the power receiving / distributing device 5. This is because the years are substantially the same. Hereinafter, in the present embodiment, the service life of the sensor insulator 1 is used as the use time.

  Before describing the update of the second correlation, the tendency of the second correlation will be described. FIG. 8 is a diagram in which the average value of the surface resistivity for each year of use is plotted for about 1500 sensor insulators 1 used in the on-site power distribution equipment 5. In FIG. 8, the vertical axis represents the logarithmic value of the surface resistivity, and the horizontal axis represents the linear value of years of use. The surface resistivity of the sensor insulator 1 is a value measured by a conventional method at a humidity of 50% RH (RH: relative humidity).

  The surface resistivity data may include errors due to environmental factors such as NOx. However, the number of samples is about 1500, and this number of samples is considered to be sufficient to grasp the aging tendency of the surface resistivity.

  As can be seen from FIG. 8, the correlation (second correlation) between the logarithm of the surface resistivity of the sensor insulator 1 and the years of use of the sensor insulator 1 can be expressed by a straight line. Hereinafter, this straight line is referred to as a master curve.

  As described above, in the second correlation update step S4, the second correlation that is a correlation between the surface resistivity B calculated based on the first correlation and the years of use of the sensor insulator 1 is obtained. Update. As a specific example of the method of updating the second correlation, for example, there is a method of sequentially updating the master curve at a frequency of about once every three months using the least square method.

Alternatively, since the second correlation is a linear relationship as described above, the following simple update method, that is, a method of updating the second correlation only at the time of diagnosis may be used. FIG. 7 is a schematic diagram for explaining the second correlation updating method. As shown in FIG. 7, the sensor insulator data (surface resistivity) at the time of remaining life diagnosis is shown in the data (surface resistivity C and years of use (0 years)) of the sensor insulator at the start of use. B and the number of years of use D (30 years)) are added to update the second correlation. Here, the surface resistivity C of the unused sensor insulator 1 is a preset value, for example, a value already known from experience. The surface resistivity B (5.0 × 10 ⁹ Ω / □ (Ω / sq)) shown in FIG. 7 corresponds to the surface resistivity B calculated from the first correlation shown in FIG. As shown in FIG. 7, a master curve is created by connecting a data plot of unused sensor insulators and a data plot of sensor insulators at the time of diagnosis with a straight line.

(Remaining life calculation step S5)
Next, the remaining life of the power receiving and distributing device 5 is obtained based on the second correlation updated in the second correlation update step S4. In this embodiment, based on the second correlation shown in FIG. 7, the life years F corresponding to the predetermined threshold E of the surface resistivity are calculated, and received based on the life years F and the service years D. The remaining life of the power distribution device 5 is obtained. The life years F here are equivalent to the years of use at the point where the straight line (master curve) representing the second correlation in FIG. 7 intersects the reference line indicating the predetermined threshold E of the surface resistivity.

The predetermined threshold E of the surface resistivity is set to, for example, the highest surface resistivity among the surface resistivity at which discharge occurs at a predetermined humidity. In the present embodiment, it is assumed that the predetermined threshold E of the surface resistivity is set to 10 ⁹ Ω / □.

  In the case of FIG. 7, the life years F are 34 years, which is the number of years of use at the point where the master curve intersects the reference line indicating the predetermined threshold value E of the surface resistivity. The number of years (4 years) obtained by subtracting the service life D (30 years) at the time of remaining life diagnosis from the life years F (34 years) is obtained as the remaining life of the power receiving and distributing device 5. In this way, the remaining life of the power receiving / distributing device 5 at a humidity of 50% RH is obtained.

  In the method for diagnosing the remaining life of a power receiving / distributing device comprising the above steps, the amount of each of ions (nitrate ions, sulfate ions and chloride ions) having a strong correlation with a decrease in the surface resistivity of the insulator is obtained (measurement step S1). ), The amount of each ion is subjected to multivariate analysis (analysis step S2), and the surface resistivity of the sensor insulator is calculated from the analysis result and the first correlation (surface resistivity calculation step S3). Therefore, even if ions that do not contribute to the decrease in surface resistivity exist on the insulator, the surface resistivity of the insulator can be obtained accurately and accurately. Thereby, it is the same or equivalent material as the sensor insulator 1, and the remaining life of the insulator provided in the power receiving and distributing device 5 can be diagnosed with high accuracy. As a result, electrical troubles due to deterioration of the insulator provided in the power receiving and distributing device 5 can be prevented in advance.

Further, in the surface resistivity calculation step S3, by setting the predetermined humidity to 50% RH, the linearity of the first correlation can be improved, and the remaining life of the power receiving / distributing device can be diagnosed more accurately. Can do. Further, by setting the threshold value of the surface resistivity when the predetermined humidity is 50% RH to 10 ⁹ Ω / □, the dielectric breakdown of the insulator provided in the power receiving and distributing device 5 at the humidity of 50% RH can be prevented in advance. be able to.

  In addition, when the second correlation is updated only at the time of diagnosis in step S3, it is not necessary to perform the sequential update, so that the measurement cost and the measurement load can be reduced.

  The method described above is a method for diagnosing the remaining life when the humidity in the installation environment is 50% RH.

  Next, a remaining life diagnosis method when the humidity in the installation environment is any humidity other than 50% RH (for example, humidity 90% RH) will be described.

  FIG. 9 is a schematic diagram for explaining the second correlation as in FIG. 7. According to the remaining life diagnosis method for power receiving and distributing equipment shown here, the predetermined threshold E of the surface resistivity in step S4 is changed according to the humidity assumed for the remaining life. In FIG. 9, the predetermined threshold E of the surface resistivity assumed for the remaining life at a humidity of 50% RH is X (Ω / □), and the predetermined threshold of the surface resistivity assumed for the remaining life at a humidity of 90% RH. The case where E is Y (Ω / □) is shown. In this case, in order to obtain the remaining life at a humidity of 90% RH, first, the life years G, that is, in FIG. 9, a reference line indicating Y (Ω / □) where the master curve is a predetermined threshold E of the surface resistivity Find the age of use at the point where Then, the remaining life of the power receiving and distributing device 5 is obtained by subtracting the service life D at the time of remaining life diagnosis from the life years G.

  Thus, by changing the predetermined threshold value of the surface resistivity according to the humidity assumed for the remaining life, the second correlation is used even at any humidity other than the humidity 50% RH. The remaining life of the power receiving / distributing device 5 can be obtained.

  Next, the reason why nitrate ions, sulfate ions, and chloride ions have a strong correlation with the decrease in surface resistivity of the unsaturated polyester insulator that is an insulator according to the present embodiment will be described. Conventionally, it has been considered that the decrease in the surface resistivity of unsaturated polyester insulators is mainly caused by dust. Since this dust tends to progress from the upper side to the lower side, the surface of the sensor insulator is arranged facing upward so that the dust adheres to the surface of the sensor insulator.

  However, it has been found that the main cause of the decrease in surface resistivity is not dust but ions such as NOx and SOx in the atmosphere. FIG. 10 is a schematic cross-sectional view for explaining an example of the deterioration mechanism of the sensor insulator due to NOx or SOx in the atmosphere. FIG. 10 shows how NOx in the atmosphere adheres to the surface of the sensor insulator. As described above, the insulator is made of unsaturated polyester resin 13 including calcium carbonate 11 and glass fiber 12.

  As shown in FIG. 10A, nitric acid is generated by the reaction between NOx in the atmosphere and water in the atmosphere. Then, as shown in FIG. 10B, in the vicinity of the surface of the sensor insulator, the nitric acid reacts with the calcium carbonate 11 which is the filler of the sensor insulator to generate calcium nitrate 14. Since calcium nitrate is a deliquescent ionic compound, it dissolves in the absorbed water and ionizes to produce nitrate ions. Such a degradation mechanism reduces the surface resistivity of the sensor insulator.

  Although the sensor insulator has been described here, in the present embodiment, the insulator included in the power receiving / distributing device is the same or equivalent material as the sensor insulator, and therefore, in the insulator of the power receiving / distributing device, The surface resistivity is lowered by the same mechanism. Further, the sensor insulator has been described as being made of an insulator containing calcium carbonate 11 as a filler. However, since the calcium carbonate 11 is present in the natural air, even if the sensor insulator is an insulator that does not contain the calcium carbonate 11 as a filler, for example, hydrated alumina, the surface resistivity is also the same. descend. Although the NOx deterioration mechanism has been described here, the SOx deterioration mechanism is substantially the same, and SOx generates sulfate ions as ions. For the above reasons, nitrate ions and sulfate ions were selected as ions having a strong correlation with the decrease in the surface resistivity of the unsaturated polyester insulator.

  In addition, the influence of sea salt (sodium chloride) has been pointed out as a cause of the decrease in the surface resistivity of insulators. Since the influence of this sea salt cannot be ignored, the chloride ion was selected as an ion having a strong correlation with the decrease in the surface resistivity of the unsaturated polyester insulator.

  These NOx, SOx, and sea salt tend to travel in the direction of air flow rather than traveling from the upper side to the lower side like dust. Therefore, the deterioration mechanism is not necessarily accelerated on the surface of the sensor insulator 1 facing upward, and the deterioration mechanism is accelerated in a place where the air flow is remarkable. Therefore, even if the surface of the sensor insulator 1 faces downward, if the air flow is significant, the progress of the insulation deterioration due to the deterioration mechanism is relatively faster than other places in the electric chamber 4. There is a case.

  In the present embodiment, as shown in FIG. 3, the surface of the sensor insulator 1 is arranged to face the bus duct 6, and the surface of another sensor insulator 1 is arranged to face the pit 7. doing. In other words, the sensor insulator 1 is disposed in the opening where the air flow is remarkable and the progress of the insulation deterioration due to the deterioration mechanism is relatively faster than other places in the electric chamber 4. Since the remaining life of the insulator provided in the power receiving and distributing device is diagnosed based on the surface resistivity of the sensor insulator 1 arranged in such a manner, it is possible to reliably prevent electrical troubles due to dielectric breakdown.

  In addition, if the sensor insulator 1 is attached to each power receiving / distributing device 5, each row of the power receiving / distributing devices 5, or each electric room 4, it is possible to grasp the progress of the deterioration degree in each unit. As a result, the renewal frequency can be ranked for each unit, and electrical trouble can be prevented in advance, and the renewal cost can be optimized.

  In the present embodiment, the method of updating the second correlation only at the time of diagnosis in the second correlation update step S4 has been mainly described, but the present invention is not limited to this. For example, in the second correlation update step S4, the second correlation may be sequentially updated using the least square method. In this case, compared with the case where the second correlation is updated only at the time of diagnosis, the measurement cost and the measurement load are applied, but as described above, the remaining life of the power receiving and distributing device 5 can be accurately diagnosed. Electrical troubles due to deterioration of the insulator can be prevented in advance.

<Embodiment 2>
In the first embodiment, the second correlation is updated only at the time of diagnosis. However, the measurement in the measurement step S1 (measurement of each amount of nitrate ion, sulfate ion, and chloride ion by the ion selective electrode). ) Was sequentially performed from the start of use of the sensor insulator 1. On the other hand, in the present embodiment, in the measurement step S1, the sensor insulator 1 is installed when the power receiving / distributing device is not used (before the start of use), and after the sensor is used for a certain period (for example, 20 years), The amount of ions of the insulator 1 is sequentially measured.

  According to this method, since the frequency of using the ion selective electrode can be reduced, the frequency of maintenance and replacement can be reduced. In this way, an economical diagnosis is possible. Since the general life of the power receiving and distributing device 5 is as long as 30 years, this effect is useful. Even if measured in this way, the surface resistivity of the sensor insulator 1 when not in use is known, and the deterioration mechanism of the sensor insulator 1 is not related to voltage. The accuracy of the remaining life of the power receiving / distributing device 5 is not deteriorated.

<Embodiment 3>
In Embodiment 1, the method for diagnosing the remaining life of power receiving and distributing equipment has been described mainly for the case where the insulator includes an unsaturated polyester resin. When the insulator contains a phenolic resin, measurement of nitrate ion, sulfate ion, ammonium ion, calcium ion and chloride ion, which has a strong correlation with the decrease in surface resistivity of the insulator containing phenolic resin, The remaining life of the power receiving / distributing device can be diagnosed in the same manner as in the first mode. That is, using the sensor insulator in which a plurality of ion selective electrodes for measuring each of nitrate ion, sulfate ion, ammonium ion, calcium ion and chloride ion are provided on the surface of the phenol insulator, By the same process, the remaining life of a power receiving and distributing device including an insulator including a phenol resin can be diagnosed.

  In addition, when the insulator contains an epoxy resin, by measuring nitrate ion, sulfate ion, ammonium ion, calcium ion and chloride ion, which has a strong correlation with the decrease in surface resistivity of the insulator containing the epoxy resin, It is possible to diagnose the remaining life of a power receiving / distributing device including an insulator including an epoxy resin.

  DESCRIPTION OF SYMBOLS 1 Sensor insulator, 100 insulator, 2 ion selection electrode, 3 Wetting device, 4 Electric room, 5 Power receiving / distributing device, 6 Bus duct, 7 Pit, 8 Forced ventilation opening, 9 Outside air, 10 Indoor air, 11 Calcium carbonate, 12 Glass fiber, 13 Unsaturated polyester, 14 Calcium nitrate, A Multivariate analysis result, B, C Surface resistivity, D Years of use, E Predetermined threshold, F Lifespan years.

Claims (3)

A remaining life diagnosis method for obtaining a remaining life of a power receiving and distributing device including an insulator,
A sensor installation step in which a sensor insulator made of the same or equivalent material as that of the insulator is provided in advance in the power receiving and distributing device,
A measurement step of sequentially measuring the amount of two or more types of ions on the surface of the sensor insulator;
An analysis step of obtaining the first correlation is a correlation between the amount of pre-SL two or more ionic surface resistivity of the sensor insulator multivariate analysis,
For the sensor insulator, before SL on the basis of the first correlation, from the amount of the two or more types of ions, and the surface resistivity calculation step of calculating the surface resistivity of the sensor insulator,
A second correlation update step of sequentially updating a second correlation, which is a correlation between the surface resistivity of the sensor insulator and the service life, using the surface resistivity calculated in the surface resistivity calculation step. When,
Based on the second correlation updated in the second correlation update step, a remaining life calculation step for obtaining a remaining life of the power receiving and distributing device,
The sensor insulator includes an insulator and a plurality of ion selective electrodes for measuring the amount of the two or more types of ions installed on the surface thereof,
The ion selection electrode is made of a conductive material, and is a method for diagnosing a remaining insulation life of a power receiving and distributing device. The method for diagnosing a remaining insulation life of a power receiving / distributing device according to claim 1 , wherein the two or more types of ions are selected from the group consisting of nitrate ions, sulfate ions, and chloride ions, and the insulator includes an unsaturated polyester resin. . The power distribution device according to claim 1 , wherein the two or more types of ions are selected from the group consisting of nitrate ions, sulfate ions, ammonium ions, calcium ions, and chloride ions, and the insulator includes a phenol resin or an epoxy resin. Insulation remaining life diagnosis method.

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