Deterioration diagnosis method, deterioration diagnosis device, and monitoring system

Abstract

Provided is a deterioration diagnosis method comprising: a step (S1) in which both an insulator and metal thin films having different film thicknesses are brought into contact with a specific gas, and a database defining a first correlation between the film thickness of the metal thin film and a surface resistivity of the insulator when the metal thin film breaks is created in advance; a step (S2) in which a metal thin film having a first film thickness is disposed around an insulator of a high-voltage electrical device; a step (S4) in which, at the time the metal thin film breaks, a corrosion rate is calculated from the time required until breakage, and a second film thickness, which is a film thickness of the metal thin film that breaks at the usage time of the high-voltage electrical device which is the time until the metal thin film breaks, is estimated; and a step (S5) in which the surface resistivity of the insulator of the high-voltage electrical device at the time when the metal thin film breaks is estimated from the estimated second film thickness and the first correlation.

Description

Deterioration diagnosis method, deterioration diagnosis apparatus and monitoring system

[0001] The present disclosure relates to a deterioration diagnosis method, a deterioration diagnosis apparatus and a monitoring system.

[0002] Conventionally, a deterioration diagnosis method for diagnosing deterioration of high-voltage electrical equipment including an insulator is known. The applicant has also proposed a method of diagnosing deterioration of high-voltage electrical equipment by accurately estimating the surface resistivity of an insulator used in high-voltage electrical equipment, which is one of the factors causing aged deterioration of high-voltage electrical equipment (see, for example, Patent Document 1).

[0003] In the deterioration diagnosis method disclosed in Patent Document 1, as shown in FIG. 5, when both the insulator to be diagnosed and the metal thin film wiring are in contact with a specific gas, a database defining a first correlation between the resistance value of the metal thin film wiring and the surface resistivity of the insulator is prepared in advance. Then, the surface resistivity of the insulator to be diagnosed at the measurement timing of the resistance value of the metal thin film wiring installed in newly installed high-voltage electrical equipment is estimated, and the remaining life of the diagnosis target is estimated from a deterioration straight line representing a second correlation between the surface resistivity of the insulator and the service life of the high-voltage electrical equipment.

[0004] International Publication No. 2021 / 166095, Japanese Unexamined Patent Application Publication No. 2002-372561

[0005] The deterioration diagnosis method disclosed in Patent Document 1 uses metal wiring with a fine pattern such as a comb shape, so that the temporal change in the resistance value of the metal thin film wiring can be measured with high accuracy, and the first correlation between the resistance value of the metal thin film wiring and the surface resistivity of the insulator can be obtained with high accuracy. However, in order to acquire the resistance value of the metal thin film wiring with high accuracy beyond the range shown in FIG. 5 of Patent Document 1, for example, even in the initial stage of corrosion, further thinning is required. Furthermore, since the first correlation between the resistance value of the metal thin film wiring and the surface resistivity of the insulator is for measuring aged deterioration of high-voltage electrical equipment from a newly installed panel, even if the metal thin film wiring is used for high-voltage electrical equipment in an existing panel and the change in resistance value is measured, it is not possible to estimate the corresponding surface resistivity of the insulator and estimate the remaining life. Therefore, development of a deterioration diagnosis method applicable to high-voltage electrical equipment in existing panels has been expected.

[0006] Furthermore, in Patent Document 2, which is cited as background art for Patent Document 1, the applicant proposes an insulation diagnostic sensor that can be applied to existing panels. However, as described in the problems of Patent Document 1, measuring the surface resistivity of an insulating material requires high-performance measuring equipment such as a high-resistivity meter.

[0007] This disclosure provides technology to solve the above-mentioned problems, and aims to provide a deterioration diagnosis method and monitoring system that uses a sensor with a simple structure and is applicable to high-voltage electrical equipment in existing control panels.

[0008] The deterioration diagnosis method of the present disclosure is a deterioration diagnosis method for diagnosing the deterioration of high-voltage electrical equipment including an insulator, comprising: a step of bringing the insulator and a metal thin film of different thicknesses together into contact with a specific gas, and creating a database in advance that defines a first correlation between the thickness of the metal thin film and the surface resistivity of the insulator when the metal thin film breaks; a step of placing the metal thin film having a first thickness around the insulator of the high-voltage electrical equipment; a step of calculating the corrosion rate from the time required until the metal thin film having the first thickness placed around the insulator breaks, and estimating a second thickness, which is the thickness of the metal thin film that breaks based on the usage time of the high-voltage electrical equipment in which the metal thin film is placed up to the time the metal thin film breaks; and a step of estimating the surface resistivity of the insulator of the high-voltage electrical equipment in which the metal thin film is placed when the metal thin film having the first thickness breaks, using the estimated second thickness and the first correlation.

[0009] Furthermore, the deterioration diagnostic device of this disclosure is a deterioration diagnostic device for diagnosing the deterioration of high-voltage electrical equipment including an insulator, comprising: a metal thin film having a first thickness disposed around the insulator; a database that predefines a first correlation between the thickness of the metal thin film and the surface resistivity of the insulator when the metal thin film breaks when the insulator and the metal thin film of different thicknesses are brought into contact with a specific gas; and a measuring unit that measures the resistance value of the metal thin film having the first thickness. An estimation unit that determines whether the metal thin film has broken off based on the measured resistance value of the metal thin film having the first thickness, and if it is determined that it has broken off, calculates the corrosion rate of the metal thin film from the time required until the break, estimates a second thickness of the metal thin film that breaks off based on the usage time of the high-voltage electrical equipment in which the metal thin film is located up to the time the metal thin film having the first thickness breaks off, and estimates the surface resistivity of the insulator of the high-voltage electrical equipment in which the metal thin film is located at the time the metal thin film has broken off using the estimated second thickness and the first correlation in the database; a relational expression creation unit that creates a deterioration line of the surface resistivity of the insulator, which is a relational expression representing the second correlation, using the surface resistivity of the insulator of the high-voltage electrical equipment in which the metal thin film has broken off, the usage time of the high-voltage electrical equipment, and the surface resistivity of the insulator before use; and a lifespan calculation unit that calculates the lifespan of the high-voltage electrical equipment corresponding to the reference surface resistivity when the insulator loses its insulating performance in the deterioration line. The system includes a lifespan calculation unit that calculates the remaining lifespan of the high-voltage electrical equipment by subtracting from the lifespan the usage time of the high-voltage electrical equipment on which the metal thin film having the first thickness is placed until the metal thin film breaks.

[0010] According to this disclosure, it is possible to provide a deterioration diagnosis method, deterioration diagnosis device, and monitoring system applicable to high-voltage electrical equipment in existing control panels using a sensor with a simple structure.

[0011] This is a schematic cross-sectional view showing the configuration of a switchgear, which is an example of high-voltage electrical equipment. This is a diagram showing the configuration of a corrosion sensor used in the deterioration diagnosis device according to Embodiment 1. This is a diagram showing the configuration of a metal thin film sensor element that constitutes the corrosion sensor used in the deterioration diagnosis device according to Embodiment 1. This is a diagram showing the configuration of another metal thin film sensor element that constitutes the corrosion sensor used in the deterioration diagnosis device according to Embodiment 1. This is a flowchart showing the procedure of the deterioration diagnosis method according to Embodiment 1. This is a diagram showing the relationship between the film thickness of the metal thin film and the time of wire breakage. This is a diagram showing the change in surface resistivity of the insulator over time. This is a diagram showing the relationship between the film thickness of the metal and the surface resistivity of the insulator at the time of wire breakage. This is a diagram showing the relationship between the years of service of the high-voltage electrical equipment and the surface resistivity of the insulator. This is a functional block diagram showing the configuration of the deterioration diagnosis device according to Embodiment 1. This is a hardware configuration diagram of the deterioration diagnosis unit. This is another hardware configuration diagram of the deterioration diagnosis unit. This is a functional block diagram showing the configuration of the deterioration diagnosis device according to Embodiment 2. This is a flowchart showing the flow of the deterioration diagnosis method according to Embodiment 2. This is a diagram showing the relationship between the years of service of the high-voltage electrical equipment and the surface resistivity of the insulator. This is a functional block diagram showing the configuration of the deterioration diagnosis device according to Embodiment 3. This is a flowchart showing the flow of the deterioration diagnosis method according to Embodiment 3. This figure shows the relationship between the service life of high-voltage electrical equipment and the surface resistivity of the insulator. This figure shows the configuration of a metal thin film sensor element that constitutes a corrosion sensor used in the deterioration diagnostic device according to Embodiment 4. This figure shows the configuration of another metal thin film sensor element that constitutes a corrosion sensor used in the deterioration diagnostic device according to Embodiment 4. This figure shows the schematic configuration of the monitoring system according to Embodiment 5.

[0012] The following description of this embodiment will be made with reference to the figures. In each figure, the same reference numerals indicate the same or corresponding parts.

[0013] Embodiment 1. Hereinafter, a deterioration diagnosis method and deterioration diagnosis apparatus according to Embodiment 1 will be described with reference to the figures. The deterioration diagnosis method according to Embodiment 1 is a deterioration diagnosis method for high-voltage electrical equipment equipped with an insulator. High-voltage electrical equipment consists of main circuit components such as circuit breakers, disconnectors, transformers, busbars and conductors, and measuring instruments.

[0014] <Example of High-Voltage Electrical Equipment: Configuration of a Switchgear> Figure 1 is a schematic cross-sectional view showing the configuration of a switchgear, which is an example of high-voltage electrical equipment. The switchgear 900 includes main circuit components such as circuit breakers, disconnectors, busbars and conductors supported by an insulator, and measuring instruments. In Figure 1, the X, Y, and Z axes are orthogonal to each other. In the explanation of Figure 1, the positive direction of the Z axis is considered the upper side, and the negative direction of the Z axis is considered the lower side.

[0015] Referring to Figure 1, the switchgear 900 comprises circuit breakers 90a and 90b, three horizontal busbars 92, connecting conductors 93a, 94a, 93b, and 94b, a busbar support plate 96, cables 97a and 97b, and a plurality of insulators 98. Circuit breaker 90a includes an operating mechanism 91a and a molded frame 95a. Circuit breaker 90b includes an operating mechanism 91b and a molded frame 95b. The connecting conductors 93a, 94a, 93b, and 94b are supported by a plurality of insulators 98. The three horizontal busbars 92 each correspond to one of the three phases of a three-phase AC power system. The busbar support plate 96 supports the three horizontal busbars 92 together.

[0016] A molded frame 95a, which houses the operating mechanism 91a and the circuit breaker (not shown), is mounted on a trolley 99a. A molded frame 95b, which houses the operating mechanism 91b and the circuit breaker (not shown), is mounted on a trolley 99b. The trolleys 99a and 99b are movable in the X-axis direction. One end of the connecting conductor 93a is electrically connected to the cable 97a. The other end of the connecting conductor 93a is electrically connected to the upper terminal of the circuit breaker 90a. One end of the connecting conductor 94a is electrically connected to the lower terminal of the circuit breaker 90a. The other end of the connecting conductor 94a is electrically connected to one end of the connecting conductor 93b via the horizontal busbar 92. The other end of the connecting conductor 93b is connected to the upper terminal of the circuit breaker 90b. One end of the connecting conductor 94b is connected to the lower terminal of the circuit breaker 90b. The other end of the connecting conductor 94b is electrically connected to the cable 97b.

[0017] Each of the mold frames 95a, 95b, busbar support plate 96, or insulator 98 is an insulator and is subject to deterioration diagnosis in this disclosure. Examples of materials for the insulator include polyester resin, epoxy resin, or phenolic resin.

[0018] The corrosion sensor 10 used in the deterioration diagnostic device according to this embodiment 1 is formed separately from the object to be diagnosed and is installed around the object to be diagnosed. In Figure 1, the corrosion sensor 10 is installed near the mold frame 95b, which is an insulator. By forming the corrosion sensor 10 separately from the object to be diagnosed, electric field concentration from the corrosion sensor 10 to the object to be diagnosed can be suppressed. In addition, the corrosion sensor 10 can be easily replaced.

[0019] <Configuration of Corrosion Sensor 10> Next, the configuration of the corrosion sensor 10 will be explained using Figures 3 and 2A and 2B. Figure 2 shows the structure of the corrosion sensor 10, which has a chip resistor type metal thin film sensor element 11, and the electrodes 7a and 7b of the metal thin film sensor element 11 are connected to wiring 3a and 3b via a connecting material 4 such as solder and mounted on a circuit board 3. The circuit board 3 may have other sensors mounted on it, or it may be a board dedicated to the corrosion sensor 10. A voltage is applied to the metal thin film sensor element 11 from a measuring unit, which will be described later, via wiring 3a and 3b to the opposing electrodes 7a and 7b.

[0020] Figure 3A shows the configuration of the metal thin-film sensor element 11 that constitutes the corrosion sensor. The metal thin-film sensor element 11 is a chip resistor type sensor element in which a metal thin film 8 of a predetermined thickness is provided on an insulating substrate 6, and electrodes 7a and 7b are provided at both ends of the metal thin film 8. Generally, a chip resistor has a structure in which a resistor is formed on a ceramic substrate, electrodes are provided at both ends, and then it is covered with a protective film. However, in the chip resistor type metal thin-film sensor element 11 according to this embodiment 1, the resistor made of a metal thin film is a flat film with no pattern formed on it, and it does not have a protective film. It has a simple structure.

[0021] Figure 3B shows another configuration of the metal thin-film sensor element 11 that constitutes the corrosion sensor. As shown in Figure 3A, electrodes 7a and 7b may be formed on the sides as long as they are connected at both ends of the metal thin film.

[0022] The corrosion sensor 10 is installed around the object to be diagnosed and is used to evaluate insulation degradation caused by exposure to a specific gas. Therefore, it is desirable that the metal material of the metal thin film 8 be a metal that can accurately evaluate the environment in which it is exposed to the specific gas (for example, copper (Cu), copper alloys, silver (Ag), silver alloys, nickel (Ni), nickel alloys, iron (Fe), and iron alloys). Other metal materials may be used as long as they can evaluate the exposure environment. Examples of methods for forming the metal thin film 8 include sputtering, vapor deposition, and plating. In addition, alumina, glass, and glass-epoxy can be used for the insulating substrate 6, and tin (Sn), tin-nickel alloy (Sn-Ni), etc., which are more resistant to the exposure environment than the metal thin film 8, can be used for the electrodes 7a and 7b. Note that the insulating substrate 6 may be made of a different material than the insulating material to be diagnosed.

[0023] <Procedure for Deterioration Diagnosis Method> Next, the deterioration diagnosis method according to Embodiment 1 will be explained using Figure 4. Figure 4 is a flowchart showing the procedure for the deterioration diagnosis method according to Embodiment 1.

[0024] First, in step S1, a database is created in advance that defines a first correlation between the thickness of the metal thin film and the surface resistivity of the insulator. Specifically, the insulator to be diagnosed, used in the switchgear 900, and the corrosion sensor 10 equipped with a chip resistor type metal thin film sensor element 11 are brought into contact with a specific gas. Multiple metal thin film sensor elements 11 with different thicknesses are prepared, and a voltage is applied to electrodes 7a and 7b while measuring the resistance value. The specific gas is a gas that affects the deterioration of the object to be diagnosed, and for example, contains nitrogen oxides (NOx) or sulfur oxides (SOx). In this embodiment 1, as an example, polyester resin was used as the insulator, and the metal thin film sensor element 11 was a copper thin film with a thickness in the range of 0.01 to 30 μm used as the metal thin film 8, and data was collected by exposing it to a gas containing nitrogen oxides (NOx).

[0025] Corrosion progresses from the surface of the insulator and the metal thin film 8 when exposed to a specific gas. The metal thin film 8 corrodes by oxidation from the surface, and the resistance between electrodes 7a and 7b increases. When the film thickness changes to oxide, the resistance value rapidly increases to more than 100 times the initial resistance, and conductivity is lost. This is referred to as a break in the circuit. When a break occurs, the time of the break and the surface resistivity of the insulator are measured. Figure 5 shows the relationship between the film thickness d of the metal thin film and the break time. As shown in Figure 5, the break time t of the metal thin film 8 is proportional to the metal film thickness d. The slope in Figure 5 indicates the corrosion rate. Furthermore, when the surface resistivity ρs of the insulator is plotted against the break time t when the metal thin film 8 breaks, the result is as shown in Figure 6. The break time t on the horizontal axis is the exposure time, and Figure 6 shows the change in the surface resistivity ρs of the insulator over time.

[0026] From these relationships, as shown in Figure 7, the relationship between the thickness d of the metal thin film 8 and the surface resistivity ρs of the insulator when the film is broken can be determined. The correlation between the thickness d of the metal thin film 8 and the surface resistivity ρs of the insulator shown in Figure 7 is called the first correlation. In step S1, this correlation is obtained in advance. Both the vertical and horizontal axes of Figure 7 are expressed on a logarithmic scale.

[0027] To obtain the first correlation, the relationship diagram shown in Figure 5 is necessary. However, it is sufficient to obtain the surface resistivity of the insulator when the metal thin film 8 breaks, starting with those with the smallest film thickness, and it is not necessary to obtain the change in the resistance value of the metal thin film 8 with high precision.

[0028] Next, in step S2, the corrosion sensor 10, equipped with a chip resistor type metal thin film sensor element 11, is placed around the insulating material to be diagnosed in an existing panel that has been in use for Ta years. The area around the object to be diagnosed is the region covered by a specific gas that affects the deterioration of the object to be diagnosed. This is the position shown in Figure 1. In this embodiment 1, the switchgear 900 on which the corrosion sensor 10 is placed is an existing panel, but it may also be a new panel. In this case, the number of years of use Ta = 0. The longer the switchgear 900 of the existing panel has been in use, the thinner the metal thin film 8 of the metal thin film sensor element 11 on which it is placed should be.

[0029] In step S3, the resistance value of the metal thin film 8 of the corrosion sensor 10 installed on the switchgear 900 is measured. As described above, the resistance value is measured to detect when the metal thin film 8 is broken. Therefore, it is not necessary to obtain information on the change in resistance value over time, and information such as whether or not a preset resistance value that can be determined to be broken has been reached may be obtained.

[0030] In step S3, if the resistance value of the metal thin film 8 of the corrosion sensor 10 increases and it is determined that the metal thin film 8 has broken, the process proceeds to step S4. After installing the corrosion sensor 10 (metal thin film 8), the film thickness dx at the time of metal thin film breakage T1 (= Ta + Tb) is estimated from the metal thin film 8 breakage time Tb and film thickness d, assuming that the metal thin film 8 had been placed from the newly installed panel.

[0031] <Example 1 of estimating film thickness at the time of metal thin film breakage in step S4> A corrosion sensor 10 with a metal thin film 8 with a thickness of 0.05 μm was placed in an existing panel that had been in use for 20 years (Ta = 20), and it broke after 0.5 years (Tb). In that case, if the film thickness at the time of metal thin film breakage T1 (= Ta + Tb = 20 + 0.5), which is determined in step S3 from the corrosion rate in Figure 5, is dx μm, then it can be calculated as follows: 0.05 μm: 0.5 years = dx μm: (20 + 0.5) years dx = 2.05 μm

[0032] Next, in step S5, the surface resistivity of the insulator is estimated by comparing the first correlation with the film thickness dx at the time of metal thin film breakage when the metal thin film 8 was placed from the newly installed panel, as estimated in step S4. Specifically, using Figure 7, the surface resistivity ρsA of the insulator is estimated when the metal thin film 8 has a thickness dx.

[0033] Next, in step S6, a degradation line for the surface resistivity of the insulator is created using the surface resistivity ρs0 of the insulator before use and the surface resistivity ρsA of the insulator estimated in step S5. Figure 8 shows the relationship between the number of years of use T of the switchgear and the surface resistivity ρs of the insulator. This is an example of creating a degradation line DC for the surface resistivity of the insulator using point D00 where the surface resistivity ρs0 is at 0 years of use and point D1 where the surface resistivity ρsA is at 1 year of use. Here, in the estimation example 1 described above, T1 = 20.5 years.

[0034] Next, in step S7, the lifespan TL (lifetime) corresponding to the threshold surface resistivity ρsδ (reference surface resistivity) is calculated from the degradation line DC. The threshold ρsδ is the surface resistivity when the object to be diagnosed loses its insulating performance and discharge occurs in the object to be diagnosed. By subtracting the number of years of service T1 of the switchgear when the metal thin film 8 breaks from the lifespan TL, the remaining lifespan TRL (=TL-T1) is calculated.

[0035] As described above, even if a corrosion sensor 10 having a metal thin film 8 with a predetermined thickness is installed on an existing switchgear 900 panel, it becomes possible to diagnose the deterioration of the insulator of the switchgear 900. Conventional metal wiring requires the formation of a pattern with high precision and the placement of the wiring on a new panel to accurately measure the change in resistance. However, in this embodiment, it can be applied to existing panels, and no processing of wiring patterns, etc., is required, making it simple and low-cost to manufacture.

[0036] Furthermore, in step S5, by comparing the threshold surface resistivity ρsδ with the surface resistivity ρsA of the insulator estimated in step S5, it is possible to determine whether or not the remaining lifespan has been reached, although the remaining lifespan cannot be calculated.

[0037] <Configuration of the Degradation Diagnosis Device> Next, a degradation diagnosis device that performs the degradation diagnosis method according to Embodiment 1 will be described. Figure 9 is a functional block diagram showing the configuration of the degradation diagnosis device according to Embodiment 1. The degradation diagnosis device 100 comprises a corrosion sensor 10 arranged around the insulator 95 to be diagnosed in the switchgear 900 and equipped with the above-mentioned chip resistor type metal thin film sensor element 11, a measurement unit 20 for measuring the resistance value of the metal thin film sensor element 11, a degradation diagnosis unit 30, and an output device 40.

[0038] The measurement unit 20 has the function of applying a predetermined voltage to the electrodes 7a and 7b of the metal thin film sensor element 11 and measuring the output value of the metal thin film sensor element 11, and is configured as a circuit meter like a tester. The measured output value of the metal thin film sensor element 11 is input to the deterioration diagnosis unit 30 (step S2). The measurement timing may be periodic or irregular, but the longer the service life of the switchgear 900 equipped with the insulating material to be diagnosed, the shorter the measurement timing period should be. The measurement unit 20 and the corrosion sensor 10 constitute the measurement device.

[0039] The degradation diagnosis unit 30 includes an estimation unit 31, a relational expression creation unit 32, a lifespan calculation unit 33, a remaining lifespan calculation unit 34, and a database 35. The output value of the measured metal thin film sensor element 11 is input to the degradation diagnosis unit 30, but it may also be received and input via an input device (not shown), such as a keyboard, mouse, or communication. The database 35 stores the first correlation relationship, which is the correlation between the film thickness d of the metal thin film 8 acquired in step S1 and the surface resistivity ρs of the insulator, as well as other data necessary for degradation diagnosis.

[0040] The estimation unit 31 determines whether the metal thin film 8 has broken off based on the output value of the metal thin film sensor element 11 mounted on the corrosion sensor 10, which is input from the measurement unit 20. If it is determined that the metal thin film 8 has broken off, the estimation unit 31 estimates the film thickness dx at the time of metal thin film breakage T1 (= Ta + Tb) if the metal thin film 8 had been placed from the time of new installation, based on the metal thin film 8's breakage time Tb and film thickness d after the corrosion sensor 10 (metal thin film 8) was installed. Using the estimated film thickness dx, the estimation unit 31 compares it with the first correlation stored in the database 35 to estimate the surface resistivity ρsA of the insulator when the metal thin film 8 has a thickness dx. That is, the estimation unit 31 executes steps S4 and S5. As described above, the determination of whether or not the metal thin film 8 has broken off can be made, for example, by comparing a preset threshold value that can be determined to be broken with the measured resistance value.

[0041] The relational expression creation unit 32 creates a surface resistivity deterioration straight line DC for an insulator. The database 35 stores a previously obtained surface resistivity ρs0 of the insulator before use (T=0). The surface resistivity deterioration straight line DC for the insulator is created using this value and the surface resistivity ρsA of the insulator after T1 years of use (step S6). That is, the relational expression creation unit 32 executes step S6.

[0042] The life calculation unit 33 calculates the life years TL (life time) corresponding to the surface resistivity threshold ρsδ (reference surface resistivity) from the deterioration straight line DC created by the relational expression creation unit 32 (step S7). The remaining life calculation unit 34 calculates the remaining life TRL (=TL-T1) by subtracting the service years T1 of the switchgear when the metal thin film 8 is broken from the life years TL on the deterioration straight line DC (step S7). That is, the life calculation unit 33 and the remaining life calculation unit 34 execute step S7.

[0043] The output device 40 outputs a deterioration diagnosis result based on the remaining life calculated by the deterioration diagnosis unit 30, and is, for example, a wireless device, a printer, or a display, and is at least one of these. The output deterioration diagnosis result may include not only the remaining life TRL of the switchgear 900, but also the life years TL and the deterioration straight line DC. Further, the output device 40 is not only provided in the deterioration diagnosis device 100, but may also be provided externally, or may be provided only externally.

[0044] FIG. 10A is a diagram showing an example of the hardware configuration of the deterioration diagnosis unit 30. The deterioration diagnosis unit 30 includes an arithmetic processing circuit 1000, a read-only memory (ROM: Read Only Memory) storing programs for executing the functions of each functional unit, and a storage device 2000 including a random access memory (RAM: Random Access Memory) for storing various data of execution results of each functional unit, which are arithmetic results obtained by the programs, and various acquired data.

[0045] The arithmetic processing circuit 1000 includes a processor configured using a CPU (CPU: Central Processing Unit), and this processor may be configured by a digital signal processor (DSP: Digital Signal Processor) or a logic circuit. Dedicated hardware may be applied to the arithmetic processing circuit 1000. When the arithmetic processing circuit 1000 is dedicated hardware, the arithmetic processing circuit 1000 corresponds to, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a combination of these. In addition, each component and the functional units included therein may implement their functions in an arithmetic processing circuit as dedicated hardware, and implement other functions by software. Thus, the respective functions described above can be implemented by hardware, software, or a combination thereof.

[0046] FIG. 10B is a diagram showing another example of the hardware configuration of the deterioration diagnosis unit 30, and is an example further including a communication circuit 3000. The communication circuit 3000 may use, as a communication module, one compliant with, for example, LTE (Long Term Evolution), 4G (4th Generation; fourth generation mobile communication system), or 5G (5th Generation; fifth generation mobile communication system). In addition, as short-range communication, Wi-Fi (registered trademark), Bluetooth (registered trademark), or the like, which are wireless LAN (LOCAL AREA NETWORK), can be used.

[0047] For example, when acquiring the output value of the metal thin-film sensor element 11 mounted on the corrosion sensor 10 from the measurement unit 20, communication can be used when the deterioration diagnosis unit 30 and the measurement device are separated from each other. In that case, the measurement unit 20 may also be provided with a communication circuit. In addition, when outputting a diagnosis result from the deterioration diagnosis unit 30, the diagnosis result may be transmitted to an external output device 40.

[0048] As described above, according to Embodiment 1, in a deterioration diagnosis method for diagnosing the deterioration of high-voltage electrical equipment including an insulator, a database is created in advance that defines a first correlation between the thickness of the metal thin film and the surface resistivity of the insulator when the metal thin film breaks, by bringing both the insulator and a metal thin film of different thicknesses into contact with a specific gas. A metal thin film having the first thickness is placed around the insulator of the high-voltage electrical equipment, and a deterioration diagnosis is performed. When the metal thin film having the first thickness breaks, the corrosion rate is calculated from the time required until the break, and a second thickness, which is the thickness of the metal thin film that breaks based on the usage time of the high-voltage electrical equipment up to the time the metal thin film breaks, is estimated. Using the estimated second thickness and the first correlation, the surface resistivity of the insulator of the high-voltage electrical equipment when the metal thin film breaks is estimated, and the deterioration diagnosis of the high-voltage electrical equipment is performed. This method uses a patternless thin metal film as a corrosion sensor, and by detecting breaks in the thin metal film, the corrosion rate of the thin metal film is calculated to estimate the progression of deterioration of the insulator. Therefore, it is possible to provide a deterioration diagnosis method that can be applied to high-voltage electrical equipment in existing control panels using a sensor with a simple structure.

[0049] Furthermore, by using the surface resistivity of the insulator of the high-voltage electrical equipment when the metal thin film breaks, the operating time of the high-voltage electrical equipment, and the surface resistivity of the insulator before use, a second correlation, a degradation line of the surface resistivity of the insulator, is created. On this degradation line, the lifespan of the high-voltage electrical equipment corresponding to the reference surface resistivity when the insulator loses its insulating performance is calculated, and the operating time of the high-voltage electrical equipment up to the time the metal thin film breaks is subtracted from the lifespan to calculate the remaining lifespan of the high-voltage electrical equipment. Thus, the remaining lifespan can be estimated for high-voltage electrical equipment in existing panels.

[0050] Furthermore, according to Embodiment 1, in a deterioration diagnostic device for diagnosing the deterioration of high-voltage electrical equipment including an insulator, a database that defines a first correlation between the thickness of the metal thin film and the surface resistivity of the insulator when a metal thin film having a first thickness, placed around the insulator, and the insulator and metal thin films of different thicknesses are brought into contact with a specific gas, a measuring unit that measures the resistance value of the metal thin film, and a unit that determines whether or not the metal thin film has broken based on the measured resistance value of the metal thin film, and if it is determined that it has broken, calculates the corrosion rate of the metal thin film from the time required until the break, and estimates a second thickness, which is the thickness of the metal thin film that will break based on the usage time of the high-voltage electrical equipment up to the time the metal thin film breaks. The device comprises: an estimation unit that estimates the surface resistivity of the insulator of high-voltage electrical equipment when the metal thin film breaks, using the estimated second film thickness and the first correlation in the database; a relational expression creation unit that creates a deterioration line for the surface resistivity of the insulator, which is a relational expression representing the second correlation, using the surface resistivity of the insulator of high-voltage electrical equipment when the metal thin film breaks, the usage time of the high-voltage electrical equipment, and the surface resistivity of the insulator before use; a lifespan calculation unit that calculates the lifespan of the high-voltage electrical equipment corresponding to the reference surface resistivity when the insulator loses its insulating performance in this deterioration line; and a lifespan calculation unit that calculates the remaining lifespan of the high-voltage electrical equipment by subtracting the usage time of the high-voltage electrical equipment up to the time the metal thin film breaks from the lifespan. Since a metal thin film without a pattern is used as a corrosion sensor, a complex manufacturing process is unnecessary, allowing for the use of a low-cost corrosion sensor with a simple structure. Because the corrosion rate of the metal thin film is calculated by detecting the break in the metal thin film to estimate the progression of deterioration of the insulator, there is no need to detect minute changes in the resistance value of the metal thin film as in the conventional method, and a deterioration diagnostic device applicable to high-voltage electrical equipment in existing panels can be provided.

[0051] Embodiment 2. The deterioration diagnosis method and deterioration diagnosis apparatus according to Embodiment 2 will be described below with reference to the figures. In Embodiment 2 as well, the target of deterioration diagnosis is high-voltage electrical equipment equipped with an insulator. It is known that the surface resistivity of an insulator decreases as humidity increases, so the accuracy of deterioration diagnosis can be improved by comparing the humidity for which the first correlation was obtained with the humidity of the existing panel where the corrosion sensor 10 is placed and making a correction. On the other hand, the resistance value of a thin metal film does not change with humidity. Also, since the surface resistivity of an insulator and the resistance value of a thin metal film change slightly with temperature, it is desirable to obtain the temperature along with the resistance value in order to measure a more accurate resistance value. For the above reasons, it is desirable to place a temperature and humidity sensor so that both humidity and temperature can be obtained, or to place a temperature sensor together with a humidity sensor. In Embodiment 2, an example will be described in which a humidity sensor is placed together with the corrosion sensor 10 around the insulator 95 that is the target of diagnosis in an existing panel that has been in use for Ta years.

[0052] <Configuration of the Degradation Diagnosis Device> Figure 11 is a functional block diagram showing the configuration of the degradation diagnosis device according to Embodiment 2, in which a humidity sensor 15 is arranged around the insulating material 95 to be diagnosed together with a corrosion sensor 10 as in Figure 9. In Embodiment 2, the measuring device consists of a corrosion sensor 10, a measuring unit 20, and a humidity sensor 15. The humidity information acquired by the humidity sensor 15 is input to the estimation unit of the degradation diagnosis unit 30.

[0053] <Procedure for Degradation Diagnosis Method> Figure 12 is a flowchart showing the procedure for the degradation diagnosis method according to Embodiment 2. The differences from the flowchart in Figure 4 of Embodiment 1 will be explained in detail. First, in step S1A, a database 35 is created in advance that defines the first correlation between the film thickness of the metal thin film and the surface resistivity of the insulator. At this time, humidity and temperature are also acquired and used as the reference humidity. Furthermore, when acquiring the first correlation in Figure 7, it is preferable that the humidity and temperature fluctuate little.

[0054] Next, in step S2A, the corrosion sensor 10 and humidity sensor 15, which are equipped with chip resistor type metal thin film sensor elements 11, are placed around the insulating material to be diagnosed in the existing panel that has been in use for Ta years, and the humidity and temperature at the time of installation are measured.

[0055] In step S3A, the resistance value of the metal thin film 8 of the corrosion sensor 10, which is installed on the switchgear 900, is measured along with humidity and temperature.

[0056] Steps S4 to S6 are the same as in Figure 4 of Embodiment 1. That is, if the estimation unit 31 determines in step S4 that the metal thin film 8 of the corrosion sensor 10 has broken, the process proceeds to step S4, and after the corrosion sensor 10 (metal thin film 8) is installed, the thickness dx at the time of metal thin film breakage T1 (= Ta + Tb) is estimated from the metal thin film 8 breakage time Tb and thickness d, assuming that the metal thin film 8 had been placed from the newly installed panel.

[0057] Next, in step S5, the estimation unit 31 estimates the surface resistivity ρsA of the insulator by comparing the film thickness dx at the time of metal thin film breakage when the metal thin film 8 was placed from the newly installed panel, as estimated in step S4, with the first correlation in the database 35.

[0058] Next, in step S6, the relational equation creation unit 32 creates a degradation line for the surface resistivity of the insulator using the surface resistivity ρs0 of the insulator before use and the surface resistivity ρsA of the insulator at the estimated number of years of use T1 in step S5. The degradation line DC1 created at this time is shown in Figure 13.

[0059] In step S8, the relational equation creation unit 32 corrects the linear degradation DC1 of the surface resistivity of the insulator based on the temperature and humidity at the time of corrosion sensor installation and the time of wire breakage of the metal thin film.

[0060] Specifically, in Figure 13, point Da corresponding to the service life Ta of the switchgear 900 when the corrosion sensor 10 is placed is plotted on the degradation line DC1, and the surface resistivity ρsa of the insulator at that time is obtained. Point D1 is the point corresponding to the service life T1, and the humidity and temperature at point Da and the humidity and temperature at point D1 are used to correct the slope of the degradation line DC1 from the humidity characteristics of the surface resistivity of the insulator. For example, in the operating environment of the switchgear 900 with the corrosion sensor 10 placed, if the humidity is higher than the reference humidity for which the first correlation was obtained, the slope becomes larger and is corrected as shown in degradation line DC3. On the other hand, in the operating environment of the switchgear 900, if the humidity is lower than the reference humidity, the slope becomes smaller and is corrected as shown in degradation line DC2.

[0061] In step S7, the lifespan calculation unit 33 calculates the lifespan in years TL (lifetime) corresponding to the threshold surface resistivity ρsδ (reference surface resistivity) from the corrected degradation line DC. The remaining lifespan calculation unit 34 calculates the remaining lifespan TRL (= TL - T1) by subtracting the number of years T1 of use of the switchgear when the metal thin film 8 breaks from the calculated lifespan in years TL.

[0062] According to Figure 13, in the operating environment of the switchgear 900 on which the corrosion sensor 10 is located, if the humidity is higher than the reference humidity for which the first correlation was obtained, the lifespan will be TL3 based on the degradation line DC3, which is shorter than the lifespan TL1 before correction. Therefore, the remaining lifespan is also estimated to be shorter. On the other hand, in the operating environment of the switchgear 900, if the humidity is lower than the reference humidity, the lifespan will be TL2 based on the degradation line DC2, which is longer than the lifespan TL1 before correction. Therefore, the remaining lifespan is also estimated to be longer. The correction is made in this manner.

[0063] As described above, Embodiment 2 provides the same effects as Embodiment 1. Furthermore, by using a humidity sensor to correct the degradation line of the surface resistivity of the insulator, which is the second correlation, with respect to relative humidity, the lifespan of the high-voltage electrical equipment and the remaining lifespan of the high-voltage electrical equipment are calculated, so that a highly accurate degradation diagnosis can be performed that takes into account the effect of humidity on the insulator.

[0064] Embodiment 3. Hereinafter, a deterioration diagnosis method and deterioration diagnosis apparatus according to Embodiment 3 will be described with reference to the figures. In Embodiment 3 as well, the target of deterioration diagnosis is high-voltage electrical equipment equipped with an insulator. In Embodiments 1 and 2, a corrosion sensor 10 placed around the insulator of the switchgear 900 was described as one example, but in Embodiment 3, an example will be described in which multiple corrosion sensors 10 are arranged, each having a metal thin film 8 with a different film thickness.

[0065] <Configuration of the Degradation Diagnosis Device> Figure 14 is a functional block diagram showing the configuration of the degradation diagnosis device according to Embodiment 3, and is an example in which two sets of measuring devices, a corrosion sensor 10A and a measuring unit 20A, and a corrosion sensor 10B and a measuring unit 20B, are arranged around the insulating material 95 to be diagnosed in Figure 9.

[0066] <Procedure for Deterioration Diagnosis Method> Figure 15 is a flowchart showing the procedure for the deterioration diagnosis method according to Embodiment 3. The differences from the flowchart in Figure 4 of Embodiment 1 will be explained in detail.

[0067] First, in step S1, a database 35 is created in advance that defines a first correlation between the film thickness of the metal thin film and the surface resistivity of the insulator.

[0068] Next, in step S2B, corrosion sensors 10A and 10B, each equipped with a chip resistor type metal thin film sensor element 11, are placed around the insulating material to be diagnosed in an existing panel that has been in use for Ta years. Here, the thickness d1 of the metal thin film 8 of corrosion sensor 10A and the thickness d2 of the metal thin film 8 of corrosion sensor 10B are different, with the thickness of the metal thin film 8 of corrosion sensor 10B being greater.

[0069] In step S3B, the resistance values ​​of the metal thin films 8 of the corrosion sensors 10A and 10B, which are arranged on the switchgear 900, are measured by the measuring units 20A and 20B and input to the estimation unit 31.

[0070] In step S3B, if the estimation unit 31 determines that the metal thin film 8 of the corrosion sensor 10A has broken, it proceeds to step S4, where, after installing the corrosion sensor 10A (metal thin film 8), it estimates the film thickness dx1 at the time of metal thin film breakage T1 (= Ta + Tb1) from the metal thin film 8 breakage time Tb1 and film thickness d1, assuming that the metal thin film 8 had been placed from the newly installed panel.

[0071] Next, in step S5, the estimation unit 31 uses the film thickness dx1 at the time of metal thin film breakage when the metal thin film 8 was placed from the newly installed panel, which was estimated in step S4, to compare it with the first correlation stored in the database 35 and estimate the surface resistivity of the insulator.

[0072] Next, in step S6A, the relational equation creation unit 32 creates a degradation line for the surface resistivity of the insulator using the surface resistivity ρs0 of the insulator before use and the surface resistivity ρsA1 of the insulator estimated in step S5. Figure 16 shows the created degradation line DC1.

[0073] Next, in step S7, the life calculation unit 33 calculates the lifespan TL1 (life time) corresponding to the threshold surface resistivity ρsδ (reference surface resistivity) from the degradation line DC1. The remaining lifespan calculation unit 34 calculates the remaining lifespan TRL1 (=TL1-T1) by subtracting the number of years of use T1 of the switchgear when the metal thin film 8 breaks from the lifespan TL1.

[0074] Returning to step S3B, the resistance value of the metal thin film 8 of the corrosion sensor 10B, which is not disconnected, is measured by the measuring unit 20B.

[0075] In step S3B, if the estimation unit 31 determines that the metal thin film 8 of the corrosion sensor 10B has broken, it proceeds to step S4, where, after installing the corrosion sensor 10B (metal thin film 8), it estimates the film thickness dx2 at the time of metal thin film breakage T2 (= Ta + Tb2) if the metal thin film 8 had been placed from the newly installed panel, based on the metal thin film 8's breakage time Tb2 and film thickness d2.

[0076] Next, in step S5, the estimation unit 31 uses the film thickness dx2 to compare it with the first correlation stored in the database 35 and estimates the surface resistivity ρsA2 of the insulator.

[0077] Next, in step S6A, the relational equation creation unit 32 plots the value of the surface resistivity ρsA2 of the insulator at the usage time T2 onto the already created degradation line DC1 and corrects the degradation line DC1. Here, let's assume that it has been corrected to the degradation line DC4 as shown in Figure 16. In step S7, the lifespan calculation unit 33 calculates the lifespan TL2 (lifespan time) corresponding to the threshold value ρsδ (reference surface resistivity) of the surface resistivity from the corrected degradation line DC4. The remaining lifespan calculation unit 34 calculates the remaining lifespan TRL2 (=TL2-T2) by subtracting the usage time T2 of the switchgear when the metal thin film 8 of the corrosion sensor 10B broke from the lifespan TL2.

[0078] In the example described above, an example was shown using two corrosion sensors 10A and 10B, each equipped with a metal thin film 8 of different thicknesses. However, the number of corrosion sensors is not limited to two; three or more corrosion sensors, each equipped with a metal thin film 8 of different thicknesses, may be provided. For example, if a corrosion sensor 10C (not shown) equipped with a metal thin film 8 having a thickness d3 greater than the thickness d2 is further placed on the switchgear 900, this should also be taken into consideration when correcting the degradation line, as shown in Figure 16.

[0079] Furthermore, although an example has been shown in which two corrosion sensors 10A and 10B are equipped with measuring units 20A and 20B respectively, the invention is not limited to this. By connecting multiple corrosion sensors 10 in parallel or multiple metal thin-film sensor elements 11 in parallel, the measuring unit 20 can be made common, thereby reducing the space required for arranging the measuring unit 20.

[0080] Furthermore, it goes without saying that the humidity sensor shown in Embodiment 2 can also be used in combination.

[0081] <Example of setting film thickness dn> Next, we will explain examples of setting different film thicknesses dn. When using metal thin films with a thickness in the range of 0.01 to 30 μm, for example, they can be classified into a thin first film thickness, a medium thickness second film thickness, and a thick third film thickness, depending on the film thickness. (1) In the case of newly installed panels or existing panels with a short service life, if at least one first film thickness is included, the rest can be set from the second and third film thicknesses. When the metal thin film 8 with the first film thickness breaks, first, the degradation line of the surface resistivity of the insulator can be obtained. Since the remaining lifespan is sufficiently long, the accuracy of the degradation diagnosis can be improved by correcting the degradation line when the remaining metal thin films 8 with the remaining film thicknesses break.

[0082] (2) In the case of existing panels with a long service life, one first film thickness is included, and the film thickness of that thickness is set to decrease as the service life increases. For the remaining layers, multiple layers are set from the range of the second and third film thicknesses, with the film thickness decreasing as the service life increases. When the metal thin film 8 with the smallest first film thickness breaks, the degradation line of the surface resistivity of the insulator can be obtained first. The remaining life is expected to be short, but the remaining life can be determined, and the accuracy of the degradation diagnosis can be improved by correcting the degradation line when the remaining metal thin films 8 with sufficient film thickness break.

[0083] As described above, Embodiment 3 provides the same effects as Embodiments 1 and 2. Furthermore, since metal thin films of different thicknesses are arranged, the number of points used when creating the degradation line of the surface resistivity of the insulator increases, making it possible to perform a more accurate degradation diagnosis.

[0084] Embodiment 4. Embodiment 4 describes an example in which a fixed resistor is connected in series with the metal thin film 8 of the metal thin film sensor element 11 provided in the corrosion sensor 10, as in Embodiment 1.

[0085] <Configuration of Metal Thin Film Sensor Element 11> Figure 17A shows the configuration of a metal thin film sensor element 11 that constitutes a corrosion sensor used in the degradation diagnostic device according to Embodiment 4, and Figure 17B shows another configuration of the metal thin film sensor element 11. In Figures 17A and 17B, a fixed resistor 9 is connected in series to the metal thin film 8 between electrodes 7a and 7b. The fixed resistor 9 is made of a material that has resistance to specific gases, for example, ruthenium oxide (RuO ２Oxide semiconductors such as ) or metals such as tin (Sn) can be used. As shown in the figure, the metal thin film 8 and the fixed resistor 9 are shown to be the same thickness, but it is not necessary for them to be the same thickness. The resistance value should be set to be greater than the initial metal thin film 8, and equal to or less than the resistance value when the metal thin film 8 oxidizes and breaks.

[0086] For example, let's assume the fixed resistor 9 has a resistance of 1000 kΩ. The initial combined resistance R0 of the metal thin film sensor element 11, in which the metal thin film 8 and the fixed resistor 9 are connected in series, is 1000 kΩ, which is negligible considering the resistance of the metal thin film 8. However, as corrosion progresses and a break occurs, the resistance of the metal thin film 8 increases, and at the time of breakage, the combined resistance RX will exceed 1000 kΩ. For example, if the combined resistance at which a break is detected is set to Rref = 1020 kΩ beforehand, even if the resistance of the metal thin film 8 fluctuates during the process leading up to breakage, the presence of the fixed resistor 9 prevents misdiagnosis of a break, and a break can be detected when the combined resistance exceeds Rref. In other words, when exposed to a specific gas, the metal thin film 8 corrodes and oxidizes from the surface, causing its resistance to change continuously. At this time, if there are fluctuations in the measured value due to noise, etc., in the early stages of corrosion when the resistance is small, there is a possibility of misdiagnosis of a break. However, by connecting the fixed resistor 9 in series with the metal thin film 8, misdiagnosis is eliminated, and the accuracy of deterioration diagnosis is improved. The resistance value of the fixed resistor 9 and the value of the combined resistance Rref, which is used to determine if a wire is broken, are predetermined based on the resistance value of the thin metal film, i.e., its thickness.

[0087] As shown in Figures 17A and 17B, the fixed resistor 9 can also be formed from a thin film and incorporated into the metal thin-film sensor element 11. However, the fixed resistor 9 may be provided outside the metal thin-film sensor element 11 and incorporated into the same circuit board 3.

[0088] It goes without saying that the fixed resistor 9 can also be applied to the corrosion sensor 10 shown in embodiments 2 and 3.

[0089] As described above, Embodiment 4 provides the same effects as Embodiments 1 to 3. Furthermore, since a fixed resistor is connected in series with the metal thin film, it becomes easier and more accurate to determine when the metal thin film is broken, making it possible to perform more accurate degradation diagnosis.

[0090] Embodiment 5. The monitoring system according to Embodiment 5 will be described below with reference to the figures. Figure 18 is a diagram showing the schematic configuration of the monitoring system according to Embodiment 5. The monitoring system shown in Figure 18 has a configuration that includes the deterioration diagnosis device 100 described in Embodiments 1 to 4. In Figure 18, the monitoring system is a system for efficiently carrying out maintenance and inspection work of switchgears by performing deterioration diagnosis of the insulating material of switchgears 900 installed in multiple locations using a monitoring device that monitors the area.

[0091] In Figure 18, two switchgears 900 are installed in factory A, and the resistance value of the metal thin film of each corrosion sensor 10 is measured by the measurement unit 20. This resistance value information is transmitted from the gateway GW via the network 200 to the estimation unit 31 of the deterioration diagnosis unit 30 of the monitoring device 300. Similarly, a corrosion sensor 10 is installed in the switchgear 900 installed in factory B, and the resistance value of the metal thin film is measured by the measurement unit 20. This resistance value information is transmitted from the gateway GW via the network 200 to the estimation unit 31 of the deterioration diagnosis unit 30 of the monitoring device 300. Furthermore, a corrosion sensor 10 is also installed in the switchgear 900 installed in building A, and the resistance value of the metal thin film is measured by the measurement unit 20. This resistance value information is transmitted from the gateway GW via the network 200 to the estimation unit 31 of the deterioration diagnosis unit 30 of the monitoring device 300.

[0092] The example factories A, B, and A are located in the monitoring area, which is under the jurisdiction of the monitoring device 300. The monitoring device 300 acquires information via the network 200 for performing deterioration diagnosis of the switchgears 900 located in the monitoring area.

[0093] Network 200 is, for example, the Internet. Within Factory A, Factory B, and Building A, the resistance values ​​of the metal thin film can be transmitted via wired LAN, short-range communication, Wi-Fi or Bluetooth, or mobile communication systems such as LTE, 4G, and 5G.

[0094] For example, the deterioration diagnosis unit 30 and the corrosion sensor 10 and measurement unit 20 of factory B constitute one deterioration diagnosis device 100. The same relationship exists between the deterioration diagnosis unit 30 and factory A, and between the deterioration diagnosis unit 30 and building A.

[0095] The monitoring device 300 comprises a deterioration diagnosis unit 30, an output device 40, and a control unit 50. The control unit 50 has, for example, the following functions, and its hardware is configured in the same way as the deterioration diagnosis unit 30, as shown in Figures 10A and 10B. (1) Based on the diagnosis results of the deterioration diagnosis unit 30, it plans and reviews the maintenance and inspection of each switchgear 900. It also determines whether to install additional corrosion sensors 10. (2) It verifies the database 35 of the deterioration diagnosis unit 30. It verifies whether the database 35 is appropriate based on the deterioration diagnosis of multiple switchgears 900. (3) If multiple switchgears 900 are equipped with other types of sensors, it refers to information from the other types of sensors.

[0096] One of the output devices 40a is equipped with a portable terminal or tablet, which transmits information from the deterioration diagnosis unit 30 and the control unit 50 to the output device 40a. By having workers carry the output device 40a to locations away from the monitoring device 300 or to factory A, it is possible to dispatch them to locations where switchgears 900 requiring urgent inspection are installed, and to notify them of maintenance and inspection details without omission. Furthermore, by having workers input information such as the completion of inspections and necessary equipment into the output device 40a, the control unit 50 can grasp the progress of maintenance and inspections and revise the maintenance and inspection plan accordingly.

[0097] As described above, Embodiment 5 provides a monitoring system for monitoring the deterioration of multiple high-voltage electrical equipment, including insulators, in a jurisdictional area, and for executing maintenance and inspection plans. This system includes the deterioration diagnostic device described in Embodiments 1 to 4, multiple high-voltage electrical equipment to be monitored, each with a metal thin film arranged around the insulator, a network that transmits the resistance values ​​of the metal thin films arranged on the high-voltage electrical equipment to an estimation unit, a control unit that performs maintenance and inspection plans for the high-voltage electrical equipment based on the deterioration diagnostic results of the deterioration diagnostic device, and an output device that outputs the maintenance and inspection plans for the high-voltage electrical equipment from the control unit. Therefore, the deterioration of multiple high-voltage electrical equipment within the jurisdictional area can be centrally managed, and the database can be shared and maintenance and inspection plans for multiple high-voltage electrical equipment can be efficiently executed. Furthermore, by performing deterioration diagnostics for multiple high-voltage electrical equipment using a common database, the optimization of the database can also be verified.

[0098] Furthermore, by transmitting the maintenance and inspection plans for high-voltage electrical equipment created in the control unit to the output device, which is a portable terminal, the maintenance and inspection plans can be communicated to workers carrying the terminals as needed. This also allows for efficient maintenance and inspection planning of high-voltage electrical equipment, including dispatching personnel to high-priority equipment, such as those requiring urgent attention. Moreover, by constructing such a system, it becomes possible to plan the appropriate allocation and securing of workers, enabling maintenance and inspection of high-voltage electrical equipment to be carried out with the appropriate number of personnel.

[0099] <Other Embodiments> In Figure 1, an example is shown in which the corrosion sensor 10 is installed near the molded frame 95b on the back side of the circuit breaker 90b, but this is not the only possible arrangement. Other insulating materials may be used as the target for diagnosis and the sensors may be placed around them, or multiple insulating materials may be placed around each of them. However, it is known that there is a correlation between the airflow inside the switchgear 900 and the progression of deterioration, and deterioration progresses faster upwind, so it is preferable to place the corrosion sensor 10 further upwind.

[0100] In Embodiment 3, an example was shown in which multiple corrosion sensors 10 were used, each having a different thickness of metal thin film 8 in the metal thin film sensor element 11. However, the metal thin film is not limited to being composed of a single type of metal. Since the corrosion rate differs depending on the type of metal, the slope of the degradation line in the first correlation relationship will differ. Therefore, a first correlation relationship corresponding to the type of metal is obtained. Multiple corrosion sensors 10 may each have a metal thin film sensor element 11 equipped with a metal thin film 8 of a different type of metal of the same thickness, or they may include combinations with different film thicknesses.

[0101] In embodiments 1 to 4, examples were shown in which one or more corrosion sensors 10 are installed. However, if the deterioration diagnosis indicates that there is sufficient remaining lifespan, additional corrosion sensors 10 may be installed at that time. In that case, the shorter the remaining lifespan, the better it is to install corrosion sensors 10 equipped with thin metal films 8 with smaller film thicknesses. This improves the accuracy of deterioration diagnosis, as well as the accuracy of maintenance and inspection planning, and can lead to increased efficiency. Furthermore, in embodiment 5, the control unit 50 can determine whether to install additional corrosion sensors 10.

[0102] While this disclosure describes various exemplary embodiments and examples, the various features, aspects, and functions described in one or more embodiments are not limited to the application of a particular embodiment, but are applicable individually or in various combinations to the embodiments. Accordingly, countless variations not illustrated are envisioned within the scope of the art disclosed in this specification. For example, these include modifying, adding or omitting at least one component, or extracting at least one component and combining it with a component from another embodiment.

[0103] 3: Circuit board, 3a, 3b: Wiring, 4: Connecting material, 6: Insulating substrate, 7a, 7b: Electrode, 8: Metal thin film, 9: Fixed resistor, 10, 10A, 10B: Corrosion sensor, 11: Metal thin film sensor element, 15: Humidity sensor, 20, 20A, 20B: Measurement unit, 30: Degradation diagnosis unit, 31: Estimation unit, 32: Relationship formula creation unit, 33: Life calculation unit, 34: Remaining life calculation unit, 35: Database, 40, 40a: Output device, 50: Control unit, 100: Degradation diagnosis device, 200: Network, 300: Monitoring device, 90a, 90b: Circuit breaker, 91a, 91b: Operating mechanism, 92: Horizontal busbar, 93a, 93b, 94a, 94b: Connecting conductor, 95: Insulator, 95a, 95b: mold frame, 96: busbar support plate, 97a, 97b: cable, 98: insulator, 99a, 99b: trolley, 900: switchgear, 1000: arithmetic processing circuit, 2000: memory device, 3000: communication circuit.

Claims

1. A deterioration diagnosis method for diagnosing the deterioration of high-voltage electrical equipment including an insulator, comprising: a step of bringing the insulator and a metal thin film of different thicknesses together into contact with a specific gas, and creating a database in advance that defines a first correlation between the thickness of the metal thin film and the surface resistivity of the insulator when the metal thin film breaks; a step of placing the metal thin film having a first thickness around the insulator of the high-voltage electrical equipment; a step of calculating the corrosion rate from the time required to break the metal thin film having the first thickness placed around the insulator when it breaks, and estimating a second thickness, which is the thickness of the metal thin film that breaks based on the usage time of the high-voltage electrical equipment in which the metal thin film is placed up to the time the metal thin film breaks; and a step of estimating the surface resistivity of the insulator of the high-voltage electrical equipment in which the metal thin film is placed when the metal thin film having the first thickness breaks, using the estimated second thickness and the first correlation.

2. A degradation diagnosis method according to claim 1, further comprising: creating a second correlation, which is a degradation line of the surface resistivity of the insulator, using the surface resistivity of the insulator of the high-voltage electrical equipment on which the metal thin film having the first thickness is located when the metal thin film having the first thickness is broken, the operating time of the high-voltage electrical equipment, and the surface resistivity of the insulator before use; calculating the lifespan of the high-voltage electrical equipment corresponding to the reference surface resistivity at which the insulator loses its insulating performance in the degradation line; and calculating the remaining lifespan of the high-voltage electrical equipment by subtracting the operating time of the high-voltage electrical equipment on which the metal thin film having the first thickness is located up to the time the metal thin film having the first thickness is broken from the lifespan.

3. The deterioration diagnosis method according to claim 2, wherein the deterioration line of the surface resistivity of the insulator, which is the second correlation, is corrected by relative humidity, and the lifespan of the high-voltage electrical equipment and the remaining lifespan of the high-voltage electrical equipment are calculated.

4. The deterioration diagnosis method according to claim 2 or 3, wherein the metal thin film disposed around the insulator of the high-voltage electrical equipment is a plurality of metal thin films with different first film thicknesses, the second film thickness is estimated for each first film thickness using the film thickness of the metal thin film and the disconnection time, the surface resistivity of the insulator of the high-voltage electrical equipment where the metal thin films are disposed at the time each of the plurality of metal thin films having different first film thicknesses disconnects, the surface resistivity of the insulator of the high-voltage electrical equipment where each of the plurality of metal thin films having different first film thicknesses is estimated for each second film thickness, and the surface resistivity of the insulator is disposed of using a plurality of sets of surface resistivity of the insulator of the high-voltage electrical equipment at the time each of the metal thin films corresponding to different first film thicknesses disconnects and the usage time of the high-voltage electrical equipment, and the surface resistivity of the insulator before use, thereby creating the deterioration straight line of the surface resistivity of the insulator, which is the second correlation.

5. The degradation diagnosis method according to any one of claims 1 to 4, wherein a fixed resistor is connected in series with the metal thin film.

6. A deterioration diagnostic device for diagnosing the deterioration of high-voltage electrical equipment including an insulator, comprising: a metal thin film having a first thickness disposed around the insulator; a database that pre-defines a first correlation between the thickness of the metal thin film and the surface resistivity of the insulator when the metal thin film breaks when the insulator and the metal thin film of different thicknesses are both brought into contact with a specific gas; a measuring unit that measures the resistance value of the metal thin film having the first thickness; a unit that determines whether the metal thin film has broken from the measured resistance value of the metal thin film having the first thickness, and if it is determined to have broken, calculates the corrosion rate of the metal thin film from the time required until the break, estimates a second thickness which is the thickness of the metal thin film that breaks based on the usage time of the high-voltage electrical equipment in which the metal thin film is located up to the time the metal thin film breaks, and estimates the surface resistivity of the insulator of the high-voltage electrical equipment in which the metal thin film is located at the time the metal thin film breaks using the estimated second thickness and the first correlation in the database; A deterioration diagnostic device comprising: a relational expression creation unit that creates a deterioration line for the surface resistivity of the insulator, which is a relational expression representing a second correlation, using the surface resistivity of the insulator of the high-voltage electrical equipment on which the metal thin film having the first thickness is placed when the metal thin film having the first thickness is broken, the usage time of the high-voltage electrical equipment, and the surface resistivity of the insulator before use; a lifespan calculation unit that calculates the lifespan of the high-voltage electrical equipment corresponding to the reference surface resistivity when the insulator loses its insulating performance in the deterioration line; and a lifespan calculation unit that calculates the remaining lifespan of the high-voltage electrical equipment by subtracting the usage time of the high-voltage electrical equipment on which the metal thin film having the first thickness is placed up to the time the metal thin film having the first thickness is broken from the lifespan.

7. The deterioration diagnostic device according to claim 6, further comprising a humidity sensor placed around the insulator, wherein the relational expression creation unit corrects the deterioration line of the surface resistivity of the insulator with respect to relative humidity.

8. A plurality of metal thin films with different first film thicknesses are arranged around the insulator; the estimation unit estimates the second film thickness and corresponding to the different first film thicknesses, and estimates the surface resistivity of the insulator of the high-voltage electrical equipment on which the metal thin films are arranged when each of the plurality of metal thin films with different first film thicknesses is broken; and the relational expression creation unit creates a deterioration line of the surface resistivity of the insulator, which is a relational expression representing the second correlation, using a plurality of sets of usage time of the high-voltage electrical equipment and the surface resistivity of the insulator corresponding to the different first film thicknesses, and the surface resistivity of the insulator before use.

9. The deterioration diagnostic device according to any one of claims 6 to 8, wherein a fixed resistor is connected in series with the metal thin film.

10. A monitoring system for monitoring the deterioration of multiple high-voltage electrical equipment, including insulators, in a jurisdictional area, and for executing maintenance and inspection plans, comprising: a deterioration diagnostic device according to any one of claims 6 to 9; a plurality of the high-voltage electrical equipment, the metal thin film being arranged around the insulator; a network for transmitting the resistance values ​​of the metal thin film arranged on the plurality of the high-voltage electrical equipment to the estimation unit; a control unit for executing maintenance and inspection plans for the high-voltage electrical equipment based on the deterioration diagnostic results of the deterioration diagnostic device; and an output device for outputting the maintenance and inspection plans for the high-voltage electrical equipment from the control unit.

11. The monitoring system according to claim 10, wherein the output device is a portable terminal, and the maintenance and inspection plan for the high-voltage electrical equipment is transmitted from the control unit via communication.

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