JP3112034B2 - Preventive maintenance system for substation equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a preventive maintenance system for substation equipment.

[0002]

2. Description of the Related Art In substation equipment, if an abnormality that occurs inside the equipment is left unattended, the equipment may fail due to dielectric breakdown or the like, which may lead to an accident. Therefore, by installing a preventive maintenance system in substation equipment, efforts are being made to detect and remove equipment abnormalities promptly at the precursor stage and prevent accidents.

[0003] In a conventional preventive maintenance system for substation equipment, for example, as disclosed in Japanese Patent Application Laid-Open No. 63-212878, the sampling interval for monitoring when an abnormality is detected is shorter than the sampling interval for normal operation. FIG. 8 shows an outline of monitoring in this conventional preventive maintenance system. After detecting the occurrence of abnormalities in the regular monitoring, increase the data amount of the item showing the abnormal value, and obtain a lot of information on the progress and appearance of the abnormality in the abnormality monitoring routine (shortened the sampling interval). When an incident occurs, it is possible to take appropriate measures.

A conventional preventive maintenance system is disclosed in
As described in Japanese Patent No. 50715, monitoring is performed at a specific time interval, and a measurement routine for diagnosing the cause of the abnormality when the abnormality is detected is operated, thereby promptly coping with the occurrence of the abnormality.

[0005]

In the above-mentioned prior art, regular monitoring is performed before an abnormality is detected. However, since the regular monitoring has a long monitoring interval, the time from occurrence of an abnormality to failure is short. Has a problem that a failure occurs without being able to detect an abnormality at the precursor stage.

For example, when a conductive foreign substance is mixed in a device, a partial discharge occurs and is detected as an abnormality. However, if the device is left as it is, the device may cause dielectric breakdown and an accident may occur. At this time, the time from when the partial discharge reaches a detectable level to when the dielectric breakdown occurs is often short, and may be shorter than the current regular monitoring interval of the preventive maintenance system. In this case, an accident may occur before the partial discharge is detected as a precursor of dielectric breakdown. To prevent such an accident, it is necessary to shorten the monitoring interval at all times, but for that purpose, the processing capacity of the system must be improved. In this case, the system not only increases the number of times of monitoring but also requires data analysis capability corresponding to the increase in data, which not only makes the system expensive,
There is a problem that it is technically difficult to configure the system.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and is a substation device capable of detecting an abnormality at a precursor stage and preventing an accident even when the time from occurrence of an abnormality to failure is short. The purpose of the present invention is to provide a preventive maintenance system.

[0008]

An object of the present invention is to provide a substation device.
Based on monitoring data of one or more installed sensors,
Substation equipment equipped with monitoring means for monitoring its operation status
In the preventive maintenance system, the operation results of existing substation equipment
Database that stores failure data based on
A monitoring interval of the monitoring means with reference to a database
This is achieved by providing a monitoring interval setting means . Previous
The monitoring interval changes with the elapsed operation time of the substation equipment
Depending on the degree of failure, for example, the failure occurrence rate, the target substation
Failure occurred during the operation elapsed time corresponding to the monitoring time of the equipment
When the rate is higher than a certain value, it is set shorter than when it is lower.
It is. Or, the monitoring interval is set to
Depending on the failure arrival time from raw to failure,
Before being monitored. Therefore, the target substation
Multiple data of the equipment failure arrival time
In this case, it is set shorter than the shortest failure arrival time. What
Note that the monitoring means is provided for each unit of the target substation equipment.
To set a monitoring interval that is adapted to each
May be . Furthermore, based on the operation results of existing substation equipment,
Database that stores failure data along with the elapsed operating time.
And substation equipment that references this database.
When the viewing time point corresponds to a specific period of the driving elapsed time,
Set the monitoring interval of the monitoring means shorter than other periods.
Monitoring interval setting means provided. The above features
The fixed period is a fixed period from the start of operation of the target substation equipment,
Immediately after maintenance where the sealed part of the target substation equipment was opened
From the resumption of operation of the substation for a period of time or
A short period of time after restarting the switchgear
At least one . The operation is not started during the specified period.
It is not limited to a certain period immediately after the resumption of the chair. For example, solid
Even during the period when the failure rate is high due to deterioration of peripherals
Good.

[0009]

Since the above means is provided, it is possible to set a short monitoring interval in advance when the failure occurrence rate is high or when the time from the occurrence of the abnormality to the failure is short.

That is, the frequency of occurrence of a failure in the substation equipment differs depending on the cause, location, time after the start of operation, and the like. Therefore, it is not always necessary to shorten the monitoring intervals for all causes and parts.In some cases, the monitoring of abnormalities due to conductive foreign substances may be focused on, and in some cases, the monitoring of solid insulator deterioration may be focused on. . For example, failures due to conductive foreign matter occur frequently during a limited period, such as immediately after the start of operation of the device or immediately after maintenance. In this case, the monitoring interval is shortened only for abnormalities caused by conductive foreign matter. Further, since the abnormality due to the deterioration of the solid insulator occurs 10 years or more after the start of the operation, in this case, the monitoring and diagnosis are mainly performed on the abnormality due to the solid insulator. In this way, only a limited number of factors are monitored at each time, so that the amount of processing of the system can be reduced, and as a result, the factors to be monitored intensively can be reliably determined. It is possible to perform anomaly detection and highly reliable diagnosis.

[0011]

Next, the present invention will be described in detail with reference to examples.

[Embodiment 1] FIGS. 1 to 7 show an embodiment of the present invention. This is a preventive maintenance system for substation equipment provided with monitoring means 2 for automatically monitoring the operation state of substation equipment based on monitoring data of one or more sensors 1a to 1n installed in the substation equipment. To
A database 3 relating to the failure of existing substation equipment and a monitoring interval setting means 4 for setting a monitoring interval of the monitoring means 2 based on the database 3 are provided. By doing so, when the failure occurrence rate is high, the monitoring interval such as when the time from the occurrence of the abnormality to the failure is short can be set short in advance, and even when the time from the occurrence of the abnormality to the failure is short, Thus, it is possible to obtain a preventive maintenance system for substation equipment that can detect an abnormality at a precursor stage and prevent an accident from occurring.

That is, FIG. 1 shows a preventive maintenance system for a gas insulated device 5 as an example of a substation device. In the system shown in FIG. 1, various sensors 1a, 1b, 1c... 1n for obtaining various types of information are installed at various parts of the gas insulating device 5, and the outputs of the sensors 1a, 1b, 1c.
Is read in. The monitoring interval of the monitoring means 2 is set by the monitoring interval setting means 4. The monitoring interval setting means 4 sets a monitoring interval with reference to the database 3.

As shown in FIG. 1, the gas insulated equipment 5 accommodates various switchgears such as a circuit breaker 7, a disconnecting switch 8, and a grounding switch 9 in a tank 10 having a ground potential, and has insulation performance and power dissipation. An insulating gas such as SF ₆ gas having excellent arc performance is sealed therein. Electric power is supplied from overhead wire 11 to bushing 12
And is sent to the transformer 15 via the bus composed of the center conductor 14 supported by the spacer 13, the disconnector 8, the circuit breaker 7, and the like. A lightning arrester 16 for suppressing overvoltage is usually mounted in the vicinity. The most problematic in such gas-insulated equipment 5 is an insulation breakdown accident that occurs inside the equipment due to abnormal insulation, and it is an important issue to prevent this accident beforehand. Although various factors can be considered as causes of the accident, a number of inspections and tests have been carried out between the assembly at the factory and the on-site installation test, and efforts have been made to eliminate these accident factors. However, it is impossible to completely eliminate them, and it is important to monitor them even after entering the operation state from the viewpoint of improving the reliability of the gas insulated equipment 5. The present embodiment is a preventive maintenance system that reliably detects an abnormality that may cause an accident under an operating condition.

Various sensors 1a, 1b, 1c... 1n for obtaining various information at various parts of the gas insulation equipment 5 include partial discharge detectors,
An acoustic sensor, an AE sensor, a decomposition gas sensor, and the like are used. The outputs of the sensors are subjected to signal amplification, extraction of necessary frequency components, frequency spectrum analysis, and the like by the detection means 6, and the results are read into the monitoring means 2. Monitoring means 2
Is used by the diagnostic means 17 for diagnosing the operating state of the gas insulated equipment 5, and the presence or absence of an abnormality in the gas insulated equipment 5 is determined based on the diagnosis result. The diagnosis result is displayed on the display means 18 as necessary, and stored in the data storage means 19. In the data storage means 19,
The operating status is stored together with the diagnosis result. The stored data is output to the diagnosis means 17 as needed, and is used again for diagnosis. In some cases, an operation stop may be instructed from the diagnosis result, or the diagnosis result may be transmitted to a higher-level diagnosis device.

The system of this embodiment includes, in addition to the above system, a monitoring interval setting means 4 for setting a monitoring interval of the monitoring means 2 and a database 3 to which the monitoring interval setting means 4 refers. The database 3 includes, for example, the relationship between various failure occurrence rates and the number of years of operation of the existing gas insulated equipment as shown in FIG. 3, or the data from the occurrence of abnormality to various failures as shown in FIG. The relation between time and years of operation has been stored as statistical data. Failures of gas-insulated equipment include those caused by conductive foreign substances mixed into the equipment and those caused by deterioration of solid insulators in the equipment. Occurrence rate and time to failure may be stored. In addition, the database 3 may be updated with newly obtained data.

The monitoring interval setting means 4 is configured separately from the monitoring means 2 in FIG. 1, and can be realized by, for example, configuring them as separate hardware, or configuring them as separate programs in a multitasking computer. . In FIG. 2, the monitoring interval setting means 4 is incorporated in the monitoring routine. In any case, the monitoring interval can be set before monitoring.

With respect to the setting of the monitoring interval, for example, when the relationship between the failure occurrence rate and the number of years of operation as shown in FIG. 3 is stored in the database 3, the failure occurrence rate at a certain time can be determined by the database 3. . By shortening the monitoring interval when the failure occurrence rate is higher than at other times, it is possible to reliably detect an abnormality at a precursor stage and prevent an accident.

Various methods are conceivable for setting the monitoring interval. FIG. 5 shows an embodiment of the present invention, in which the monitoring interval is set to t ₁ when the failure occurrence rate is p ₁ or more, and the monitoring interval is set to t ₀ (> t ₁ ) when the failure occurrence rate is p ₁ or less. By doing so, the monitoring interval when the failure occurrence rate is high is set short. At this time, if it is stored relationship shown in FIG. 3 in the database, the monitoring interval failure rate is determined as p ₁ or more in operation elapsed years T is T ₁ or less is set to t _1, the operation elapsed years above T ₁ monitoring interval is determined failure incidence and p ₁ or less when the is set to t _0. If the database is known in advance, a monitoring interval can be set in advance for the number of years of operation.

When the monitoring interval is appropriately shortened as described above, the following effects can be obtained. As shown in FIG. 3, the failure occurrence rate of gas-insulated equipment is high immediately after the start of operation of the equipment, and they are often failures due to conductive foreign matter.
In this case, abnormalities are reliably detected by shortening the monitoring interval by monitoring the processing capacity of the system as much as possible. On the other hand, when the operation elapsed years T becomes T ₁₀ or more, the overall failure rate is much smaller, the spacer, the solid insulator such as bushing may lead to failure deteriorates. The T ₁₀ is often on the order of 10 years. Since the solid insulator deteriorates with time in the interior, data accumulated by past monitoring is sequentially analyzed to diagnose the deterioration state and prevent an accident. At this time, the amount of data used for diagnosis increases with the passage of time, so that processing related to deterioration diagnosis increases with time. However, when the processing amount increases, the failure occurrence rate decreases,
The monitoring interval can be set long, and the processing capacity used for monitoring immediately after the start of operation can be used for data analysis, and highly reliable diagnosis can be performed.

For example, as shown in FIG. 2, such monitoring is performed by a diagnosis unit 17a for performing a minimum necessary diagnosis immediately after monitoring the diagnosis unit and a diagnosis when there is room in the processing of the system. This can be realized by dividing the diagnostic means into a diagnosis means 17b. In the diagnosis means 17b, the data storage means 19
Diagnosis is performed with reference to data recorded in the. When the monitoring interval is set to be relatively short, the processing amount of the diagnosis unit 17b is reduced, and when the monitoring interval is set to be long, the processing amount of the diagnosis unit 17b is increased.

The following effects can also be obtained by appropriately shortening the monitoring interval. When transmission lines and power cables are added at substations, substation equipment will be added sequentially along with the addition. At this time, since the operation start time differs depending on the device, the time when the monitoring interval needs to be shortened in each device differs. Therefore, since the number of monitoring targets for which the monitoring interval should be shortened at a time is reduced, the monitoring interval can be shortened sufficiently, and the reliability is high.
And efficient monitoring can be performed. Hereinafter, this will be described.

FIG. 6 shows an example of the configuration of a substation. The gas insulating devices 5a and 5b and the transformer 15 are the main substation devices. Various sensors 1a... 1n for monitoring the insulation abnormality and the operation abnormality of each of the substation equipments 5a, 5b and the transformer 15.
Are attached, and the device monitoring terminals 20a, 20b,
20c is installed. This device monitoring terminal 20a, 2
Ob and 20c are connected to the device monitoring device 22 via the optical transmission cable 21. Device monitoring terminals 20a, 20
Each of b and 20c includes a detection unit 6 and a monitoring unit 2, and the device monitoring device 22 includes a diagnosis unit 17, a data storage unit 19, a monitoring interval setting unit 4, and a database 3.

[0024] The gas-insulated equipment 5a whereas starts running at the same time the operation start and the substation, when the gas-insulated apparatus 5b is the power cable at a later above T ₁ substation has started operation is added Installed and operational. In this case, for the monitoring interval of the gas insulated apparatus 5a, between T ₁ of the immediately following start of operation it must be shortened, the gas-insulated apparatus 5b
You don't need to be that short when you run. Therefore, when the gas insulating device 5b is operated, the monitoring interval only needs to be shortened for only the gas insulating device 5b. Therefore, the data processing amount of the device monitoring device 22 can be reduced, and the monitoring interval can be sufficiently shortened to reduce the abnormality. It can be detected reliably.

FIG. 7 shows a case where a plurality of monitoring means having different monitoring intervals are used in the substation shown in FIG. Gas insulation equipment 5a,
As device monitoring terminals for monitoring 5b, a device monitoring terminal 20s for processing monitoring with a short monitoring interval is provided in addition to 20a and 20b. During T ₁ of the immediately following start of operation of the gas-insulated equipment. 5a, equipment monitoring terminal 20s monitors the gas-insulated equipment 5a. Then, when the gas-insulated device 5b is installed later and starts operation, the device monitoring terminal 20s monitors the gas-insulated device 5b.

[0026] and removable equipment monitoring terminal 20s for processing short monitoring of the monitoring interval by further fabricated to same other substations, the gas-insulated apparatus 5b after monitored between T _1, the equipment monitoring terminal 20s Can be taken to another substation and used for monitoring at short monitoring intervals at that substation.

In the system of FIG. 1, the substation equipment is a transformer 1
5, a circuit breaker 7, a disconnecting switch 8, a grounding switch 9, a bus bar, an arrester 16, a current transformer, an instrument transformer, a bushing 12, and the like. Since the time when it is necessary to shorten the monitoring interval in such a system differs for each unit in detail, if the database 3 is a database for each unit, the failure occurrence rate of each device is obtained at each time. In particular, by shortening the monitoring interval for a unit having a high failure rate, an abnormality can be more reliably detected. Further, the monitoring interval may be set by using the database 3 as a database for each sensor and each factor.

As shown in FIG. 4, the relationship between the time from occurrence of an abnormality to various failures and the number of years of operation may be stored in the database 3 as statistical data.

A failure due to a conductive foreign substance may be detected before the failure unless the monitoring interval is sufficiently short, since the time from the occurrence of the partial discharge to the failure as a precursor of the failure is short. However, failure due to conductive materials are concentrated in a limited period, such as between T ₁ of the immediately following start of operation, very little in other periods. Therefore, if the monitoring interval is set shorter than the time (Te ₁ ) from the occurrence of the abnormality to the failure, the abnormality can be reliably detected at the precursor stage. In addition, failures due to conductive foreign substances increase during a period immediately after maintenance or immediately after the operation of various switchgears such as circuit breakers, disconnectors, and grounding switches. Therefore, the monitoring interval is shortened during that period.

Although the monitoring period after the maintenance is shortened, if the maintenance time of each device is shifted systematically and the monitoring interval is shortened only for the device immediately after the maintenance, the processing capacity required at one time is reduced. The monitoring interval can be made sufficiently short, and abnormalities can be reliably detected.

The signal level of the sensor immediately after the maintenance may be higher than that before the maintenance. In this case, it can be determined that an abnormality has occurred in the inside, and the maintenance is performed again.

If an abnormality is detected in one solid insulator, it is highly likely that at that time (eg, T ₁₀ ), an abnormality will be detected in another solid insulator cast at the same time. . Therefore, as shown in FIG. 8 , the abnormality is reliably monitored by setting the monitoring time short after detecting the abnormality with one solid insulator.

The database is updated when new data relating to the failure is obtained. In this case, before entering new data into the database, if the monitoring personnel determines that there is a risk that an error has occurred in the device, the monitoring interval shall be set immediately shortly by the monitoring personnel. With this, the abnormality is reliably detected.

As described above, according to the present embodiment, when the failure occurrence rate is high or when the time from the occurrence of an abnormality to the failure is short, the monitoring interval is shortened, so that the abnormality is reliably detected at the precursor stage, and the failure is detected. Can be prevented beforehand.

[0035]

As described above, according to the present invention, even when the time from the occurrence of an abnormality to the failure is short, the abnormality can be detected at the precursor stage and the accident can be prevented beforehand. Even when the time is short, it is possible to obtain a preventive maintenance system for substation equipment that can detect an abnormality at a precursor stage and prevent an accident from occurring.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of one embodiment of a preventive maintenance system for substation equipment according to the present invention.

FIG. 2 is an explanatory diagram of a case where a monitoring interval setting unit of the embodiment is incorporated in a monitoring routine.

FIG. 3 is a characteristic diagram showing a relationship between a number of years of operation and a failure occurrence rate.

FIG. 4 is a characteristic diagram showing a relationship between elapsed years of operation and time from occurrence of an abnormality to failure.

FIG. 5 is an explanatory diagram for determining a monitoring interval in one embodiment of the preventive maintenance system for substation equipment of the present invention.

FIG. 6 is an explanatory diagram of a preventive maintenance system for substation equipment constituting the substation according to the embodiment.

FIG. 7 is an explanatory diagram of a case where monitoring means of a plurality of different monitoring intervals according to the embodiment is used.

FIG. 8 is an explanatory diagram showing a monitoring routine of a conventional substation equipment preventive maintenance system.

[Explanation of symbols]

1a to 1n: sensors, 2: monitoring means, 3: database, 4: monitoring interval setting means, 5, 5a, 5b: gas insulating equipment.

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Shuzo Iwaasa 4026 Kuji-cho, Hitachi City, Ibaraki Prefecture Inside Hitachi, Ltd. Hitachi Research Laboratory, Ltd. (56) References JP-A-63-212878 (JP, A) JP-A-2-234298 (JP, A) JP-A-2-37432 (JP, A) JP-A-1- 248926 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01R 31/12 G01R 31/02

Claims (6)

(57) [Claims] 1. A preventive maintenance system for substation equipment provided with monitoring means for monitoring an operation state of one or more sensors connected to the substation equipment based on monitoring data of existing substation equipment. Operating elapsed time and multiple
A database that stores failure data, including the relationship with the failure occurrence rate due to failure factors, and the operating time of the target substation equipment
Forecast the failure occurrence rate with reference to the failure data,
Audit the monitoring interval of the monitoring means on the basis of the failure rates
A monitoring interval setting means for changing and setting before viewing or when updating the database is provided, and the monitoring means sets a monitoring interval by the monitoring interval setting means.
Set and short monitoring interval when the failure occurrence rate is high
Therefore, when the failure occurrence rate is low, a long monitoring interval is used.
Preventive maintenance system for substation equipment, characterized in that it can be monitored . 2. A preventive maintenance system for substation equipment provided with monitoring means for monitoring an operation state of the substation equipment based on monitoring data of one or more sensors installed in the substation equipment. A database for storing failure data including a failure arrival time from the occurrence of an abnormality to a failure based on the failure data; and a failure arrival time of the target substation equipment is predicted with reference to the failure data, and the monitoring means is shorter than the failure arrival time. A monitoring interval setting means for setting a monitoring interval of the substation equipment. 3. The substation equipment according to claim 2, wherein when a plurality of failure arrival times are referred to from the failure data, the monitoring interval is set so as to correspond to the shortest failure arrival time. Maintenance system. 4. The monitoring interval setting unit according to claim 1, wherein the monitoring interval setting means is configured to determine whether the operation time corresponds to a specific period of the operation elapsed time in the database.
A preventive maintenance system for a substation device configured to set a monitoring interval of the monitoring unit shorter than a period other than the specific period. 5. The substation device according to claim 4, wherein the specific period is a predetermined period from the start of operation of the substation device, a predetermined period from resumption of operation immediately after maintenance in which a sealed part of the substation device is opened, or the target substation device. Preventive maintenance system for substation equipment, which is a fixed period from the restart of operation immediately after the operation of the switchgear. 6. The sub-device according to claim 1, wherein the database is provided for each unit constituting the sub-device, for each type of sensor installed in the sub-device, and / or for each failure factor of the sub-device. Preventive maintenance system for substation equipment.