WO2023248299A1

WO2023248299A1 - Degradation diagnosis method and degradation diagnosis device

Info

Publication number: WO2023248299A1
Application number: PCT/JP2022/024557
Authority: WO
Inventors: 宗一郎藤原; 勝衣川; 伸介三木
Original assignee: 三菱電機株式会社
Priority date: 2022-06-20
Filing date: 2022-06-20
Publication date: 2023-12-28

Abstract

A degradation diagnosis method according to the present invention includes a step for arranging an insulation degradation sensor in the environment of an insulator. A plurality of pieces of metal wiring are connected in parallel at the insulation degradation sensor. The plurality of pieces of metal wiring include first metal wiring and second metal wiring that have different corrosion progression speeds. The degradation diagnosis method includes a step (S4) in which a combined resistance value for the insulation degradation sensor at measurement timing and a database that defines a first correlation between the combined resistance value for the insulation degradation sensor and the surface resistivity of the insulator are used to estimate the surface resistivity of the insulator at the measurement timing, a step (S6) in which a relational expression that indicates a second correlation between the surface resistivity of the insulator and the time of use of an electrical apparatus is used calculate the lifetime of the electrical apparatus, and a step (S7) in which the remaining lifetime of the electrical apparatus having subtracted the time of use of the electrical apparatus at the measurement timing is calculated from the lifetime.

Description

Deterioration diagnosis method and deterioration diagnosis device

The present disclosure relates to a deterioration diagnosis method and a deterioration diagnosis apparatus for diagnosing deterioration of electrical equipment including insulators.

Conventionally, deterioration diagnosis methods for diagnosing the deterioration of electrical equipment containing insulators have been known. For example, International Publication No. 2021/166095 (Patent Document 1) includes a database that defines the correlation between the resistance value of metal thin film wiring and the surface resistivity of insulators when coming into contact with a specific gas, and A deterioration diagnosis device has been disclosed that estimates the surface resistivity of an insulator by comparing the resistance value of a metal thin film wiring installed in the vicinity of the insulator. The deterioration diagnosis device calculates the life and remaining life of the electrical equipment from the estimated surface resistivity.

International Publication No. 2021/166095

In the technique described in Patent Document 1, if the metal thin film wiring is disconnected due to exposure to a specific gas, the surface resistivity of the insulator cannot be estimated. Therefore, the period during which deterioration of electrical equipment can be accurately diagnosed is limited.

The present disclosure has been made to solve the above-mentioned problems, and it is an object of the present disclosure to provide a deterioration diagnosis method and a deterioration diagnosis device that can accurately diagnose the deterioration of electrical equipment over a long period of time.

A deterioration diagnosis method according to one aspect of the present disclosure diagnoses deterioration of an electrical device including an insulator. The deterioration diagnosis method includes the step of arranging an insulation deterioration sensor around an insulator, in which a plurality of metal wirings that corrode when exposed to a specific gas are connected in parallel. The plurality of metal wires include first metal wires and second metal wires that have different corrosion progression rates when the insulation deterioration sensor is exposed to a specific gas. The deterioration diagnosis method further includes creating in advance a database that defines a first correlation between the combined resistance of the insulation deterioration sensor and the surface resistivity of the insulator when both the insulator and the insulation deterioration sensor are exposed to a specific gas. a step of measuring the composite resistance value of the insulation deterioration sensor at the measurement timing; a step of estimating the surface resistivity of the insulator at the measurement timing using the composite resistance value at the measurement timing and the database; The relationship between the operating time of the electrical equipment and the surface resistivity of the insulating material is determined from the operating time of the electrical equipment and the estimated surface resistivity of the insulating material, and the surface resistivity of the insulating material when the electrical equipment is not in use. a step of creating a relational expression expressing the second correlation, a step of calculating the life time of the electrical equipment corresponding to the reference surface resistivity when the insulating material loses its insulation performance in the relational expression, and a step of calculating the life time of the electrical equipment from the life time, and calculating the remaining life time of the electrical equipment by subtracting the operating time of the electrical equipment at the timing or the operating time of the electrical equipment at the timing when the insulation deterioration sensor is disposed around the insulator.

A deterioration diagnosis device according to another aspect of the present disclosure diagnoses deterioration of an electrical device including an insulator. The deterioration diagnosis device includes an insulation deterioration sensor in which a plurality of metal wirings that corrode when exposed to a specific gas are connected in parallel. The plurality of metal wires include first metal wires and second metal wires that have different corrosion progression rates when the insulation deterioration sensor is exposed to a specific gas. The deterioration diagnosis device further includes a database that defines a first correlation between the combined resistance value of the insulation deterioration sensor and the surface resistivity of the insulator when both the insulator and the insulation deterioration sensor are exposed to a specific gas; a measurement unit that measures the composite resistance value of the insulation deterioration sensor at the measurement timing; an estimation unit that estimates the surface resistivity of the insulator at the measurement timing using the composite resistance value at the measurement timing and a database; From the operating time of the equipment, the estimated surface resistivity of the insulating material, and the surface resistivity of the insulating material when the electrical equipment is not in use, the second difference between the operating time of the electrical equipment and the surface resistivity of the insulating material is calculated. A relational expression creation section that creates a relational expression expressing a correlation, a life calculation section that calculates the life time of the electrical equipment corresponding to the reference surface resistivity when the insulating material loses its insulation performance in the relational expression, and a remaining life calculation unit that calculates the remaining life time of the electrical equipment by subtracting the usage time of the electrical equipment at the measurement timing or the usage time of the electrical equipment at the timing when the insulation deterioration sensor is arranged around the insulator.

According to the deterioration diagnosis method and deterioration diagnosis device according to the present disclosure, the corrosion progression rates of the first metal wiring and the second metal wiring due to the specific gas are different from each other. Therefore, the range of the surface resistivity of the insulator, which correlates with the combined resistance value of a plurality of metal interconnections including the first metal interconnection and the second metal interconnection, becomes wider. Thereby, the surface resistivity of the insulator can be estimated accurately over a wider range. As a result, the period during which deterioration of the insulator can be accurately diagnosed becomes longer.

FIG. 1 is a cross-sectional view schematically showing the configuration of a switchgear that is an example of high-voltage electrical equipment. 3 is a flowchart showing the flow of a deterioration diagnosis method according to the first embodiment. It is a graph schematically showing the relationship between the number of years of use (hours of use) and surface resistivity of electrical equipment. 1 is a schematic diagram of an insulation deterioration sensor according to Embodiment 1. FIG. FIG. 3 is a diagram showing the relationship between the exposure time and the resistance value of the metal wiring when the metal wiring according to the first embodiment is exposed to a specific gas. FIG. 3 is a diagram showing the correlation between the surface resistivity of the insulator and the resistance value of the metal wiring when a specific gas is exposed to the insulator and the metal wiring to be diagnosed. FIG. 3 is a diagram showing the correlation between the surface resistivity of the insulator and the combined resistance value of the metal wiring when a specific gas is exposed to the insulator and the metal wiring connected in parallel. 1 is a block diagram showing a schematic configuration of a deterioration diagnosis device that executes a deterioration diagnosis method according to Embodiment 1. FIG. FIG. 9 is a hardware configuration diagram of the main parts of the control section in FIG. 8; 9 is a block diagram showing a functional configuration of a control section shown in FIG. 8. FIG. FIG. 2 is a schematic diagram of an insulation deterioration sensor according to a second embodiment. FIG. 7 is a diagram showing the relationship between the exposure time and the resistance value of the metal wiring when the metal wiring according to Embodiment 2 is exposed to a specific gas.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In addition, the same reference numerals are given to the same or corresponding parts in the drawings, and the description thereof will not be repeated in principle.

Embodiment 1.
The method of diagnosing deterioration of electrical equipment according to the first embodiment is a method of diagnosing deterioration of electrical equipment including an insulator. The electrical equipment is, for example, high-voltage electrical equipment or special high-voltage electrical equipment that includes main circuit components such as circuit breakers, disconnectors, transformers, busbars and conductors, and measuring equipment. "High voltage" means that the DC voltage is more than 750V and less than 7000V, or the AC voltage is more than 600V and less than 7000V. "Extra high voltage" means that the DC or AC voltage exceeds 7000V.

FIG. 1 is a cross-sectional view schematically showing the configuration of a switchgear 49, which is an example of high-voltage electrical equipment. The switchgear 49 includes main circuit components such as a circuit breaker, a disconnector, and a bus bar/conductor supported by an insulator, and a measuring device. In FIG. 1, the X, Y, and Z axes are orthogonal to each other. In the explanation regarding FIG. 1, the + direction of the Z-axis is assumed to be the upper side, and the - direction of the Z-axis is assumed to be the lower side.

As shown in FIG. 1, the switchgear 49 includes circuit breakers 50a, 50b, three horizontal busbars 52, connection conductors 53a, 54a, 53b, 54b, busbar support plate 56, and cables 57a, 57b. , and a plurality of insulators 58. Circuit breaker 50a includes an operating mechanism 51a and a mold frame 55a. Circuit breaker 50b includes an operating mechanism 51b and a mold frame 55b. The connection conductors 53a, 54a, 53b, and 54b are supported by a plurality of insulators 58. The three horizontal busbars 52 correspond to three phases of three-phase alternating current, respectively. The busbar support plate 56 collectively supports the three horizontal busbars 52.

A mold frame 55a containing an operating mechanism 51a and a blocking section (not shown) is mounted on a trolley 61a. A mold frame 55b containing an operating mechanism 51b and a blocking section (not shown) is mounted on a cart 61b. The carts 61a and 61b are movable in the X-axis direction. One end of the connection conductor 53a is electrically connected to the cable 57a. The other end of the connection conductor 53a is electrically connected to the upper terminal of the circuit breaker 50a. One end of the connection conductor 54a is electrically connected to a lower terminal of the circuit breaker 50a. The other end of the connecting conductor 54a is electrically connected to one end of the connecting conductor 53b via the horizontal bus bar 52. The other end of the connecting conductor 53b is connected to the upper terminal of the circuit breaker 50b. One end of the connecting conductor 54b is connected to a lower terminal of the circuit breaker 50b. The other end of the connecting conductor 54b is electrically connected to the cable 57b.

Each of the mold frames 55a and 55b, the bus bar support plate 56, or the insulator 58 is an insulator, and is a target of deterioration diagnosis (diagnosis target) in the present disclosure. Examples of the material of the insulator include polyester resin, epoxy resin, or phenol resin.

The insulation deterioration sensor 10 is formed separately from the insulator that is the object of diagnosis, and is placed around the object of diagnosis. In FIG. 1, the insulation deterioration sensor 10 is placed near the mold frame 55b. By forming the insulation deterioration sensor 10 as a separate body from the object to be diagnosed, it is possible to suppress electric field concentration from the insulation deterioration sensor 10 to the object to be diagnosed. Furthermore, the insulation deterioration sensor 10 can be easily replaced.

Next, the deterioration diagnosis method according to Embodiment 1 will be explained using FIGS. 2 and 3. FIG. 2 is a flowchart showing the flow of the deterioration diagnosis method according to the first embodiment. FIG. 3 is a graph schematically showing the relationship between the years of use (hours of use) and surface resistivity of electrical equipment.

As shown in FIG. 2, in step S1, a specific gas (for example, nitrogen oxides (NOx) or sulfur oxides (SOx)) that affects the deterioration of the diagnosis target is used in the insulation deterioration sensor 10 and the electrical equipment. Exposure (contact) to the subject being diagnosed. By measuring the resistance value of the insulation deterioration sensor 10 and the surface resistivity of the insulator after exposure, a correlation (first correlation) between the resistance value of the insulation deterioration sensor 10 and the surface resistivity of the diagnosis target is defined. A database is created in advance. Next, in step S2, the insulation deterioration sensor 10 is placed around the diagnostic target. The area around the diagnostic target is the area covered by the specific gas when the diagnostic target is exposed to the specific gas. Next, in step S3, the resistance value of the insulation deterioration sensor 10 is measured at each measurement timing using a simple resistance meter such as a tester. The resistance value is measured periodically or constantly. In step S4, the resistance value of the insulation deterioration sensor 10 measured in step S3 is checked against the database created in step S1, and the surface resistivity SR1 of the diagnosis target at the measurement timing of the resistance value is estimated. Note that the measurement timing of the resistance value at which the surface resistivity SR1 is estimated is the number of years of use L1 (years).

As shown in FIG. 3, in step S5, the correlation between the surface resistivity and the age of use of the electrical equipment (second A relational expression representing the relationship (correlation) is created. For example, the relational expression represents a deterioration straight line RF1 in which the logarithm of the surface resistivity and the number of years of use of the electrical equipment are linearly related. In step S6, the number of life years L2 (life time) corresponding to the threshold value SR2 (reference surface resistivity) of the surface resistivity is calculated from the deterioration straight line RF1. Note that the threshold value SR2 is the surface resistivity when the diagnostic target loses its insulation performance and discharge occurs in the diagnostic target. In step S7, by subtracting the service life L1 (<L2) of the diagnosis target at the measurement timing of the insulation deterioration sensor 10 or the arrangement timing of the insulation deterioration sensor 10 from the life span L2 of the diagnosis target, the remaining life RL1 of the diagnosis target (remaining life time) is calculated.

Next, details of the deterioration diagnosis method according to the first embodiment will be described using FIGS. 4 and 5. FIG. 4 is a schematic diagram of the insulation deterioration sensor 10 according to the first embodiment. As shown in FIG. 4,

metal wirings

31a and 31b connected in parallel are formed on the main surface of the insulating substrate 32. The

metal wirings

31a and 31b shown in FIG. 4 are made of metal thin films and have a comb shape. However, the ratio (L/W) of the wiring length L to the wiring width W of the

metal wirings

31a and 31b is adjusted (for example, the The shape of the

metal wirings

31a and 31b may be other than a comb shape as long as the ratio is 1000 or more). If the

metal wirings

31a, 31b are excessively thin or long, the impedance of the

metal wirings

31a, 31b increases and the detection sensitivity decreases, so the

metal wirings

31a, 31b should have appropriate widths and lengths. is desirable. Furthermore, if the

metal wirings

31a, 31b are too short, it may become difficult to form and solder the

metal wirings

31a, 31b, so it is desirable that the

metal wirings

31a, 31b have appropriate lengths. Further, from the viewpoint of suppressing an increase in the impedance of the

metal wirings

31a, 31b due to the cross-sectional area, it is desirable that the thickness of the

metal wirings

31a, 31b is 0.1 μm or more. However, it is desirable that the thickness of the

metal wirings

31a and 31b is 30 μm or less so that the

metal wirings

31a and 31b have a resistance (several hundred Ω level) that can be easily measured with a tester or the like. Furthermore, in order to measure the resistance of the

metal wires

31a, 31b, the

metal wires

31a, 31b need to be formed on an insulating substrate. Examples of the material for the insulating substrate 32 include glass, glass epoxy, or paper phenol.

The thickness or type of metal of the

metal wirings

31a, 31b is set in advance so that the rate of corrosion of the

metal wirings

31a, 31b by the specific gas when the insulation deterioration sensor 10 is exposed to the specific gas is different from each other. For example, in order to make the corrosion progression rate of the metal wiring 31b slower than the corrosion progression rate of the metal wiring 31a, the

metal wirings

31a and 31b are made of the same material, and the thickness of the metal wiring 31b is set to be larger than the thickness of the metal wiring 31a. do. Alternatively, in order to make the corrosion progression rate of the metal wiring 31b slower than the corrosion progression rate of the metal wiring 31a, the thickness of the

metal wirings

31a and 31b may be made the same, and the material of the metal wiring 31b may be made more specific than the material of the metal wiring 31a. Select materials that are less corrosive to gases.

As the metal material for the

metal wirings

31a and 31b, a metal whose exposure environment to the specific gas can be accurately evaluated, that is, a metal that corrodes when it comes into contact with the specific gas is used. Examples of metals that corrode when in contact with specific gases include copper (Cu), copper alloys, silver (Ag), silver alloys, nickel (Ni), nickel alloys, iron (Fe), and iron alloys. . However, other metal materials may be used as long as they can evaluate the exposure environment of the specific gas. Methods for forming the

metal wirings

31a and 31b include sputtering, vapor deposition, and plating, but there is no need to be limited to these methods.

An electrode pad 33a_1 is arranged near one end of the metal wiring 31a, and an electrode pad 33a_2 is arranged near the other end of the metal wiring 31a. An electrode pad 33b_1 is arranged near one end of the metal wiring 31b, and an electrode pad 33b_2 is arranged near the other end of the metal wiring 31b. Electrode pads 33a_1, 33b_1 are connected to lead wire 34_1. Electrode pads 33a_2, 33b_2 are connected to lead wire 34_2. Thereby,

metal wirings

31a and 31b are connected in parallel.

FIG. 5 is a diagram showing the relationship between the exposure time and the resistance value of the metal wiring when the metal wiring according to the first embodiment is exposed to a specific gas. FIG. 5 shows

graphs

35a, 35b, and 37 in which the horizontal axis represents exposure time and the vertical axis represents resistance value. A graph 35a shows a change in the resistance value of the metal wiring 31a between the electrode pads 33a_1 and 33a_2. Graph 35b shows a change in the resistance value of metal wiring 31b between electrode pads 33b_1 and 33b_2. A graph 37 shows a change in the resistance value between the lead wires 34_1 and 34_2, that is, the combined resistance value of the

metal wires

31a and 31b connected in parallel.

Since the corrosion progress rates of the

metal wiring

31a and 31b are different from each other, the exposure time range 36a in which the resistance value of the metal wiring 31a changes when exposed to a specific gas and the range 36a of exposure time in which the resistance value of the metal wiring 31a changes when exposed to a specific gas and the metal wiring The exposure time range 36b in which the resistance value of 31b changes has a region that does not overlap with each other. Note that the range 36a is an exposure time range in which the time rate of change in resistance value of the metal wiring 31a when exposed to the specific gas is equal to or greater than α×ΔRmax_a, where ΔRmax_a is the maximum value of the rate of change in resistance value over time. be. Similarly, the range 36b is the range of exposure time in which the time rate of change in resistance value of the metal wiring 31b when exposed to the specific gas is equal to or greater than α×ΔRmax_b, where ΔRmax_b is the maximum value of the rate of change in resistance value over time. It is. α is predetermined and is, for example, 0.1.

FIG. 6 is a diagram showing the correlation between the surface resistivity of the insulator and the resistance value of the

metal wires

31a, 31b when the insulator and the

metal wires

31a, 31b to be diagnosed are exposed to a specific gas. FIG. 6 shows a case where the thickness or type of metal of the

metal wirings

31a and 31b is set so that the rate of corrosion of the metal wiring 31b due to the specific gas is slower than the rate of corrosion of the metal wiring 31a due to the specific gas. The correlation is shown. As shown in FIG. 6, the range of surface resistivity of the insulator (1×10 ⁸ to 1×10 ¹¹ Ω/□) that correlates with the resistance value of the metal interconnect 31b correlates with the resistance value of the metal interconnect 31a. It is smaller than the range of surface resistivity of insulators (1×10 ¹¹ to 1×10 ¹⁵ Ω/□).

FIG. 7 is a diagram showing the correlation between the surface resistivity of the insulator and the combined resistance value of the

metal wires

31a, 31b when a specific gas is exposed to the insulator and the

metal wires

31a, 31b connected in parallel. The correlation shown in FIG. 7 is calculated from the correlation between the surface resistivity of the insulator and the resistance values of the

metal wirings

31a and 31b shown in FIG. As shown in FIG. 7, there is a correlation between the combined resistance value of the

metal wirings

31a and 31b connected in parallel and the surface resistivity of the insulator. By using this correlation, the surface resistivity of the insulator can be estimated from the resistance value of the insulation deterioration sensor 10 (that is, the combined resistance value of the

metal wirings

31a and 31b).

In order to further increase the accuracy of estimating the surface resistivity of the insulator, the correlation coefficient between the combined resistance value of the

metal wirings

31a and 31b connected in parallel and the surface resistivity of the insulator should be 0.5 or more. is preferred. Therefore, the thickness, metal type, width, length, etc. of the

metal wirings

31a, 31b are adjusted depending on the insulator to be diagnosed so that the correlation coefficient is 0.5 or more.

In the technique disclosed in Patent Document 1, a single metal wiring is used. For example, when the metal wiring 31a is used as a single metal wiring, the range of the surface resistivity of the insulator that correlates with the resistance value of the metal wiring is 1×10 ¹¹ to 1×10 ¹⁵ Ω/□ (Fig. (see 6). Therefore, the range in which the surface resistivity of the insulator can be estimated is also 1×10 ¹¹ to 1×10 ¹⁵ Ω/□. Furthermore, when the metal wiring is disconnected, the resistance value changes rapidly, which may lead to incorrect diagnosis.

In this embodiment,

metal wirings

31a and 31b are used which are connected in parallel and have different corrosion progression rates due to a specific gas. For example, the rate of corrosion of the metal wiring 31b caused by the specific gas is slower than the rate of corrosion of the metal wiring 31a caused by the specific gas. Therefore, the range of surface resistivity of the insulator that correlates with the combined resistance value of the

metal wirings

31a and 31b is 1×10 ⁷ to 1×10 ¹⁵ Ω/□, which correlates with the resistance value of the metal wiring 31a or the metal wiring 31b. The range is wider than the range of surface resistivity of insulators. Thereby, the surface resistivity of the insulator can be estimated accurately over a wider range. Further, even if the metal wiring 31a is disconnected, the combined resistance value does not change suddenly. Therefore, incorrect diagnosis is suppressed.

FIG. 8 is a block diagram showing a schematic configuration of a deterioration diagnosis apparatus 100 that executes the deterioration diagnosis method according to the first embodiment. As shown in FIG. 8, the deterioration diagnosis device 100 is realized in the form of a control board whose operation is controlled by a program recorded on a recording medium such as a ROM (Read Only Memory). However, the control board is an example of implementation of the deterioration diagnosis device 100, and the hardware configuration of the deterioration diagnosis device 100 is not limited to the configuration shown in FIG. 8.

The deterioration diagnosis device 100 includes an insulation deterioration sensor 10, a measurement section 20, an input section 101, a storage section 102, a control section 103, and an output section 104.

The measurement unit 20 measures the combined resistance value of a plurality of metal wirings connected in parallel in the insulation deterioration sensor 10. Specifically, the measuring unit 20 measures the resistance value between the lead wires 34_1 and 34_2 shown in FIG. 4 as the combined resistance value of the

metal wires

31a and 31b connected in parallel. The measuring unit 20 is configured by, for example, a tester, and measures the combined resistance value by applying a predetermined voltage (for example, 100 V) between the lead wires 34_1 and 34_2.

The input unit 101 includes, for example, an input device such as a keyboard, a mouse, or a tablet, and a communication port that can communicate with the measurement unit 20 or an external device. The input unit 101 receives input of data necessary for diagnosing deterioration of a diagnosis target 55 (for example, mold frames 55a, 55b). For example, the resistance value of the insulation deterioration sensor 10 when the insulation deterioration sensor 10 and the polyester insulator are exposed to a specific gas (that is, the combined resistance value of a plurality of metal wirings connected in parallel) and the surface resistivity of the polyester insulator, A database 70 defining correlations between the two is input to the input unit 101 prior to deterioration diagnosis. The database 70 is created in advance based on preliminary experiments. Alternatively, the resistance value of the insulation deterioration sensor 10 when the insulation deterioration sensor 10 and the polyester insulator are exposed to a specific gas (that is, the combined resistance value of a plurality of metal wirings connected in parallel) and the surface resistivity of the polyester insulator Resistance change data indicating a change over time may be input to the input unit 101 prior to deterioration diagnosis. Resistance change data is obtained in preliminary experiments. Further, the input unit 101 receives input of the combined resistance value measured by the measurement unit 20.

The storage unit 102 is a memory device including, for example, a ROM, a RAM (Random Access Memory), and a hard disk. The storage unit 102 stores a program for executing the deterioration diagnosis method, a database 70 for calculating the surface resistivity from the combined resistance value, various data input to the input unit 101, and the like.

The database 70 defines the correlation between the surface resistivity of the insulator and the combined resistance value of the plurality of metal wirings (see FIG. 7) when a specific gas is exposed to the insulator and the plurality of metal wirings connected in parallel. . The database 70 is created by an external device and stored in the storage unit 102 via the input unit 101. Alternatively, the database 70 may be created by the control unit 103 based on the resistance change data input to the input unit 101 and stored in the storage unit 102.

The control unit 103 is realized, for example, by a microprocessor (MPU: Micro-Processing Unit). The control unit 103 reads the program stored in the storage unit 102 and executes processing related to deterioration diagnosis according to the procedure described in the program.　　

FIG. 9 is a hardware configuration diagram of the main parts of the control unit 103 in FIG. 8. Each function of the control unit 103 can be realized by the processing circuit 1. The processing circuit 1 includes at least one processor 1b and at least one memory 1c. The processing circuit 1 may include at least one dedicated hardware 1a together with a processor 1b and a memory 1c, or as a substitute thereof.

When the processing circuit 1 includes a processor 1b and a memory 1c, each function of the deterioration diagnosis device 100 is realized by software, firmware, or a combination of software and firmware. At least one of the software and firmware is written as a program. The program is stored in the memory 1c. The processor 1b implements each function of the deterioration diagnosis device 100 by reading and executing programs stored in the memory 1c.

The processor 1b is also called a CPU (Central Processing Unit), a processing device, an arithmetic device, a microprocessor, a microcomputer, or a DSP. The memory 1c is configured of a nonvolatile or volatile semiconductor memory, such as a RAM, a ROM, a flash memory, an Erasable Programmable Read Only Memory (EPROM), an Electrically Erasable Programmable Read Only Memory (EEPROM), or the like.

When the processing circuit 1 includes dedicated hardware 1a, the processing circuit 1 may include, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), or an FPGA (Field Programmable Circuit). Gate　Array), or a combination of these.

Each of the plurality of functions of the deterioration diagnosis device 100 can be realized by the processing circuit 1. Alternatively, a plurality of functions of the deterioration diagnosis device 100 may be realized by the processing circuit 1 all at once. Regarding each function of the deterioration diagnosis device 100, a part may be realized by dedicated hardware 1a, and other parts may be realized by software or firmware. In this way, the processing circuit 1 can realize each function of the deterioration diagnosis device 100 using the hardware 1a, software, firmware, or a combination thereof.

The output unit 104 shown in FIG. 8 outputs the diagnosis result based on the remaining life calculated by the control unit 103 to the external output device 200. Output device 200 may include, for example, a wireless device, a printer, a display, or a combination thereof.

FIG. 10 is a block diagram showing the functional configuration of the control section shown in FIG. 8. As shown in FIG. 10, the control unit 103 includes an estimation unit 72, a relational expression creation unit 73, a lifespan calculation unit 74, and a remaining lifespan calculation unit 75. The estimation unit 72 estimates the surface resistivity of the object to be diagnosed. The relational expression creation unit 73 creates a relational expression between the number of years of use of the diagnostic target and the surface resistivity of the diagnostic target. The lifespan calculation unit 74 calculates the lifespan of the diagnosis target. The remaining life calculation unit 75 calculates the remaining life of the diagnostic target.

The estimating unit 72 compares the combined resistance value measured by the measuring unit 20 after the insulation deterioration sensor 10 is placed around the diagnostic target with the database 70, and estimates the surface resistivity of the diagnostic target. That is, the estimation unit 72 executes the process of step S4 in FIG.

The relational expression creation unit 73 connects the point corresponding to the estimated surface resistivity of the diagnostic target and the point corresponding to the surface resistivity of the diagnostic target whose usage age is 0 years (new or unused product) to determine the diagnostic target. Create a relational expression between the years of use and the surface resistivity of the diagnostic target. That is, the relational expression creation unit 73 executes the process of step S5 in FIG.

The lifespan calculation unit 74 calculates the number of years of lifespan of the diagnosis target based on the relational expression created by the relational expression creation unit 73 and a predetermined threshold value. That is, the life calculation unit 74 executes the process of step S6 in FIG. 2.

The remaining life calculation unit 75 subtracts the number of years of use of the diagnostic target at the measurement timing of the composite resistance value of the insulation deterioration sensor 10 or the placement timing of the insulation deterioration sensor 10 from the life years calculated by the life calculation unit 74, and calculates the remaining life. Calculate. That is, the remaining life calculation unit 75 executes the process of step S7 in FIG.

As described above, according to the deterioration diagnosis method or the deterioration diagnosis apparatus according to the first embodiment, the corrosion progress rates of the

metal wirings

31a and 31b due to the specific gas are different from each other. Therefore, the range of the surface resistivity of the insulator that correlates with the combined resistance value of the

metal wirings

31a and 31b becomes wider. Thereby, the surface resistivity of the insulator can be estimated accurately over a wider range. As a result, the period during which deterioration of electrical equipment (for example, switchgear 49) including an insulator can be accurately diagnosed becomes longer.

Embodiment 2.
In the first embodiment, the thickness or type of metal of the

metal wirings

31a, 31b is set in advance so that the rate of corrosion of the

metal wirings

31a, 31b by the specific gas is different from each other. However, one of the

metal wirings

31a and 31b may be covered with a coating film so that the rates of corrosion of the

metal wirings

31a and 31b due to the specific gas are different from each other.

FIG. 11 is a schematic diagram of an insulation deterioration sensor according to the second embodiment. The insulation deterioration sensor shown in FIG. 11 is different from the insulation deterioration sensor shown in FIG. 3 in that the metal wiring 31b is covered with a coating film 40. The coating film 40 is formed by applying a coating agent onto the metal wiring 31b.

Coating agents used include polyurethane, silicone, and silica, but are not necessarily limited to these.

A specific gas that affects the deterioration of the insulator permeates (invades) the coating film 40. Therefore, the metal wiring 31b is corroded by the specific gas. However, the resistance value of the metal wiring 31b does not change until the specific gas passes through the coating film 40 and reaches the metal wiring 31b. That is, the period until the specific gas passes through the coating film 40 and reaches the metal wiring 31b is a dead period of the metal wiring 31b. As a result, even if the

metal wirings

31a and 31b have the same thickness and the same metal type, the rate of corrosion of the metal wiring 31b is suppressed compared to the metal wiring 31a on which the coating film 40 is not formed.

FIG. 12 is a diagram showing the relationship between the exposure time and the resistance value of the metal wiring when the metal wiring according to the second embodiment is exposed to a specific gas. FIG. 12 shows

graphs

45a, 45b, and 47 in which the horizontal axis represents exposure time and the vertical axis represents resistance value. A graph 45a shows a change in the resistance value of the metal wiring 31a between the electrode pads 33a_1 and 33a_2. Graph 45b shows a change in the resistance value of metal wiring 31b between electrode pads 33b_1 and 33b_2. A graph 47 shows a change in the resistance value between the lead wires 34_1 and 34_2, that is, the combined resistance value of the

metal wires

31a and 31b connected in parallel.

Since the corrosion progression rate of the metal wiring 31b is slower than the corrosion progression rate of the metal wiring 31a, the range of exposure time in which the resistance value of the metal wiring 31a changes when the insulation deterioration sensor according to the second embodiment is exposed to a specific gas is 46a and an exposure time range 46b in which the resistance value of the metal wiring 31b changes when the metal wiring 31b is exposed to a specific gas have regions that do not overlap with each other.

The position of the range 46b depends on the length of the dead period of the metal wiring 31b. The length of the dead period of the metal wiring 31b depends on the thickness of the coating film 40. Therefore, the thickness of the coating film 40 may be adjusted so that the range 46a and the range 46b do not overlap each other. Thereby, the range of the surface resistivity of the insulator that correlates with the combined resistance value of the

metal wirings

31a and 31b becomes wider.

By forming the coating film 40, contact between the metal wiring 31b and objects (for example, people, dust, etc.) that may cause detection failure is prevented. As a result, occurrence of phenomena such as unintentional disconnection of a part of the metal wiring 31b is suppressed.

Note that the metal wiring 31a may also be covered with the coating film 40. This prevents contact between the object and the metal wiring 31a, which would cause detection failure. In this case, the thickness of the coating film 40 covering the metal wiring 31a may be set to be thinner than the thickness of the coating film 40 covering the metal wiring 31b. As a result, the rate of corrosion of the metal wiring 31b becomes slower than the rate of corrosion of the metal wiring 31a.

Embodiment 3.
In the first and second embodiments, an insulation deterioration sensor in which two

metal wirings

31a and 31b are connected in parallel is used. However, the number of metal wirings connected in parallel is not limited to two, and may be three or more. By using more metal wiring, multiple items that affect the insulation performance of the insulator can be taken into consideration, making it possible to diagnose deterioration that is more environmentally friendly.

For example, the insulation deterioration sensor may include another metal wire connected in parallel to the

metal wires

31a and 31b. The range of exposure time in which the resistance value of the other metal wiring changes when the other metal wiring is exposed to the specific gas has a region that does not overlap with the

ranges

36a and 36b corresponding to the

metal wirings

31a and 31b.

In the description of Embodiments 1 to 3, a switchgear was used as an example of an electrical device, but the electrical device is not limited to a switchgear. If an insulating material is used to insulate the current-carrying parts of electrical equipment from ground to ground or between phases, and if the configuration is to diagnose the deterioration status of the insulation performance of the insulating material, Embodiments 1 to 3 may be used in the configuration. It is possible to obtain similar effects.

Examples of electrical equipment include switch gears, power receiving and distribution equipment, transformers, control gears such as motor control centers, generators, electric motors, and power supply devices for power supply (for example, AC power supplies, DC power supplies, or rectifiers).

The above embodiments may be implemented in various other forms by omitting, replacing, or changing them without departing from the content of the disclosure. Embodiments that are omitted, replaced, or modified are also included within the scope and content of the disclosure, and within the scope and equivalent scope of the claims and their content.

It is also planned that the embodiments disclosed herein will be implemented in combination as appropriate to the extent that they do not contradict each other. The embodiments disclosed this time should be considered to be illustrative in all respects and not restrictive. The scope of the present disclosure is indicated by the claims rather than the above description, and it is intended that equivalent meanings and all changes within the scope of the claims are included.

1 processing circuit, 1a hardware, 1b processor, 1c memory, 10 insulation deterioration sensor, 20 measurement unit, 31a, 31b metal wiring, 32 insulating substrate, 33a_1, 33a_2, 33b_1, 33b-2 electrode pad, 34_1, 34_2 lead wire , 40 coating film, 49 switch gear, 50a, 50b circuit breaker, 51a, 51b operating mechanism, 52 horizontal busbar, 53a, 53b, 54a, 54b connection conductor, 55 diagnosis target, 55a, 55b mold frame, 56 busbar support plate, 57a, 57b cable, 58 insulator, 61a, 61b trolley, 70 database, 72 estimation section, 73 relational expression creation section, 74 lifespan calculation section, 75 remaining lifespan calculation section, 100 deterioration diagnosis device, 101 input section, 102 storage section, 103 control unit, 104 output unit, 200 output device.

Claims

A deterioration diagnosis method for diagnosing deterioration of electrical equipment including insulators,
arranging, around the insulator, an insulation deterioration sensor in which a plurality of metal wirings that corrode when exposed to the specific gas are connected in parallel; The deterioration diagnosing method further includes a first metal wiring and a second metal wiring that have different corrosion progression rates when exposed to
A database is created in advance that defines a first correlation between a composite resistance value of the insulation deterioration sensor and a surface resistivity of the insulator when both the insulator and the insulation deterioration sensor are exposed to the specific gas. step and
measuring a combined resistance value of the insulation deterioration sensor at a measurement timing;
estimating the surface resistivity of the insulator at the measurement timing using the combined resistance value at the measurement timing and the database;
From the operating time of the electrical equipment at the measurement timing, the estimated surface resistivity of the insulating material, and the surface resistivity of the insulating material when the electrical equipment is unused, the operating time of the electrical equipment and the estimated surface resistivity of the insulating material are determined. creating a relational expression representing a second correlation with the surface resistivity of the insulator;
In the relational expression, calculating the life time of the electrical equipment corresponding to the reference surface resistivity when the insulating material loses its insulation performance;
Calculate the remaining life time of the electrical equipment by subtracting the usage time of the electrical equipment at the measurement timing or the usage time of the electrical equipment at the timing when the insulation deterioration sensor is arranged around the insulator from the life time. A method for diagnosing deterioration, comprising the steps of:
When the insulation deterioration sensor is exposed to the specific gas, a first range of exposure time in which the resistance value of the first metal wiring changes and a second range of exposure time in which the resistance value of the second metal wiring changes. The deterioration diagnosis method according to claim 1, wherein the deterioration diagnosis method has regions that do not overlap with each other.
The deterioration diagnosis method according to claim 2, wherein the first range does not overlap with the second range.
The deterioration diagnosis method according to any one of claims 1 to 3, wherein the correlation coefficient of the first correlation is 0.5 or more.
The deterioration diagnosis method according to any one of claims 1 to 4, wherein at least one of the first metal wiring and the second metal wiring is covered with a coating film that is permeable to the specific gas. .
The electrical device according to any one of claims 1 to 5, wherein the electrical equipment includes at least one of a switchgear, a power receiving and distribution device, a transformer, a control gear, a generator, an electric motor, and a power supply device for power supply. Deterioration diagnosis method.
A deterioration diagnostic device for diagnosing deterioration of electrical equipment including insulators,
An insulation deterioration sensor is provided in which a plurality of metal wirings that corrode when exposed to a specific gas are connected in parallel, and the plurality of metal wirings have corrosion progression rates that are different from each other when the insulation deterioration sensor is exposed to the specific gas. The deterioration diagnosing device further includes different first metal wiring and second metal wiring,
a database that defines a first correlation between a combined resistance value of the insulation deterioration sensor and a surface resistivity of the insulator when both the insulator and the insulation deterioration sensor are exposed to the specific gas;
a measuring unit that measures a combined resistance value of the insulation deterioration sensor at a measurement timing;
an estimation unit that estimates the surface resistivity of the insulator at the measurement timing using the combined resistance value at the measurement timing and the database;
From the operating time of the electrical equipment at the measurement timing, the estimated surface resistivity of the insulating material, and the surface resistivity of the insulating material when the electrical equipment is unused, the operating time of the electrical equipment and the estimated surface resistivity of the insulating material are determined. a relational expression creation unit that creates a relational expression representing a second correlation with the surface resistivity of the insulator;
In the relational expression, a life calculation unit that calculates a life time of the electrical equipment corresponding to a reference surface resistivity when the insulating material loses insulation performance;
Calculate the remaining life time of the electrical equipment by subtracting the usage time of the electrical equipment at the measurement timing or the usage time of the electrical equipment at the timing when the insulation deterioration sensor is arranged around the insulator from the life time. A deterioration diagnosis device comprising a remaining life calculation unit.
When the insulation deterioration sensor is exposed to the specific gas, a first range of exposure time in which the resistance value of the first metal wiring changes and a second range of exposure time in which the resistance value of the second metal wiring changes. The deterioration diagnosis device according to claim 7, having regions that do not overlap with each other.
The deterioration diagnosis device according to claim 8, wherein the first range does not overlap with the second range.
The deterioration diagnosis device according to any one of claims 7 to 9, wherein the first correlation has a correlation coefficient of 0.5 or more.
The deterioration diagnosis device according to any one of claims 7 to 10, wherein at least one of the first metal wiring and the second metal wiring is covered with a coating film that is permeable to the specific gas. .
The electrical device according to any one of claims 7 to 11, wherein the electrical equipment includes at least one of a switch gear, a power receiving and distribution device, a transformer, a control gear, a generator, an electric motor, and a power supply device for power supply. Deterioration diagnosis device.