JP2017106750A - Insulation characteristic measuring apparatus, method for measuring insulation characteristic using the apparatus, and residual life diagnostic method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an insulation characteristic measuring apparatus that can measure insulation characteristics of a cylindrical insulating object as a measurement target under a high moisture state, independently of the outer environments, a method for measuring insulation characteristics using the apparatus, and a residual life diagnostic method.SOLUTION: There is provided an insulation characteristic measuring apparatus (1) for measuring the insulation characteristic of a cylindrical insulating object, which includes: a plurality of electrodes (3, 4) arranged on a circumference of a side surface at intervals; a closed container (2), that can form a closed space (9), covering electrodes and insulated from the outside; moisture adjusting means (5), that can keep the closed space at a constant moisture; and connectors (6, 7), connecting measuring means (8) for measuring the insulation characteristics of the cylindrical insulating object by applying a voltage between electrodes, to an electrode.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an insulation characteristic measuring apparatus capable of measuring an insulation characteristic of a cylindrical insulator in an arbitrary environmental state, an insulation characteristic measurement method using the same, and a remaining life diagnosis method.

  High-voltage power distribution equipment is a device in which a high-voltage structure is stored in a board of a certain size. A part having a large potential difference inside the switchboard is provided with a predetermined insulation strength by separating a separation distance or sandwiching an insulator. A solid insulator such as a polyester resin or an epoxy resin is used for holding the high-voltage object or a barrier. Since these insulators eventually cause a dielectric breakdown failure when their insulation performance deteriorates due to aging, there is a need for an insulation deterioration diagnosis / remaining life diagnosis technique for preventing the failure.

  The following Patent Document 1 discloses an invention relating to a method for evaluating substrate surface contamination. Specifically, as shown in FIG. 2 of Patent Document 1, a measuring instrument main body having a plurality of electrodes is provided, and the surface resistivity is measured by bringing the electrodes into contact with a substrate to be evaluated. At this time, the measurement is performed in a state where the measuring instrument main body is housed in the humidity variable chamber (see column [0018] in Patent Document 1). Thereby, since the surface resistivity can be measured while changing the humidity of the measurement air continuously or in a fragmentary manner, the relationship between the surface resistivity and the humidity can be easily grasped.

  Patent Document 2 describes an invention relating to a method for diagnosing the remaining life of a power receiving / distributing device. In Patent Document 2, a sensor insulator made of the same or equivalent material as the diagnosis target insulator included in the power receiving / distributing device is provided in advance in the power receiving / distributing device (see [0015] column of Patent Document 2). Then, the use of the sensor insulator is started simultaneously with the start of use of the power receiving / distributing device, and the surface resistivity on the surface of the sensor insulator and the humidity in the vicinity of the surface are sequentially measured. Furthermore, the relationship between the years of use and surface resistivity is derived from the relationship between humidity and surface resistivity, and a database is created. It is assumed that the years of use (remaining life) are substantially the same for sensor insulators and power distribution equipment. (See columns [0021] to [0028] in Patent Document 2).

JP 2011-149771 A JP 2009-8427 A

  However, in the invention described in Patent Document 1, the variable humidity chamber is in a state of floating from the substrate surface to be measured, and the substrate surface cannot be stably maintained in a high humidity state. Further, since the measuring instrument main body for measuring the surface resistivity is housed in the humidity variable chamber, the measuring instrument main body itself is exposed to a high humidity state, and the measuring instrument main body is likely to be deteriorated. Moreover, in the structure of patent document 1, it is made into the subject to generate a high voltage within a humidity variable chamber and to measure surface resistivity.

  Moreover, in the invention described in Patent Document 1, an insulating surface on a flat substrate is a measurement object, and for example, a cylindrical insulator such as an insulation insulator attached to a switchboard is not a measurement object. And in the structure shown in patent document 1, the insulation characteristic of the curved-surface-shaped insulating surface which is not a plane cannot be measured appropriately.

  In Patent Document 2, the remaining life of the power receiving / distributing device is estimated and evaluated based on a database measured by a sensor insulator, and high reliability cannot be obtained. In other words, the usage environment such as the voltage application state does not match between the insulating surface of the power receiving / distributing device to be originally evaluated and the sensor insulator, and the degree of deterioration is naturally different. Therefore, as in Patent Document 2, it is difficult to estimate the surface resistivity of the insulating surface with high accuracy based on the diagnosis result of the sensor insulator different from the power receiving / distributing device. Also in Patent Document 2, as in Patent Document 1, there is no disclosure regarding a configuration for maintaining a measurement environment at high humidity and a configuration for measuring a cylindrical insulator.

  The present invention has been made in view of such problems. The object of the present invention is to make a measurement object a cylindrical insulator, and in a high humidity state with respect to the cylindrical insulator regardless of the external environment. It is another object of the present invention to provide an insulation characteristic measuring apparatus capable of measuring the insulation characteristic of the semiconductor, and further to provide an insulation characteristic measuring method and a remaining life diagnosis method using the apparatus.

  The present invention is an insulation characteristic measuring apparatus for measuring an insulation characteristic of a cylindrical insulator, and includes a plurality of electrodes arranged at intervals on a side surface of the cylindrical insulator, and the plurality of electrodes. A sealing member capable of forming a sealed space isolated from the outside of the covering; a humidity adjusting means capable of maintaining the sealed space at a constant humidity; and applying a voltage between the plurality of electrodes to form the cylindrical insulator. And a connecting means for connecting the measuring means for measuring the insulating properties of the electrode to the electrode.

  In the present invention, each of the plurality of electrodes is preferably disposed on different circumferences of the cylindrical insulator.

  In the present invention, at least one of the plurality of electrodes is preferably in contact at two or more points on the same circumference of the cylindrical insulator.

  In the present invention, it is preferable that at least one of the plurality of electrodes is provided over a half circumference on the same circumference of the cylindrical insulator.

  In the present invention, the sealing member is formed of a soft material, and the sealing space is formed by tightening the sealing member on at least two circumferences of the cylindrical insulator so that the plurality of electrodes are disposed inside. It is preferably formed so as to be included.

  Moreover, in this invention, it is preferable to provide the spacer for interposing between the side surface of the said cylindrical insulator and the said sealing member, and maintaining the said sealed space.

  In the present invention, it is preferable that at least one of flow path portions for circulating air between the connection portion, the humidity adjusting means, and the sealed space is inserted into the spacer.

  In the present invention, the plurality of electrodes are respectively connected to the plurality of connection portions that electrically connect the inside and the outside of the sealed space, and at least two of the plurality of connection portions are mutually connected to the cylinder. It is preferable to arrange | position on the other side through a shape insulator.

  In the present invention, it is preferable that at least two of the plurality of connection portions are arranged in a direction in which a distance between the connection portions is away from a position facing the electrode.

  Further, the present invention is a method for measuring the insulation characteristics for a cylindrical insulator, forming a sealed space on the side surface of the cylindrical insulator, adjusting the inside of the sealed space to a constant humidity, The insulation characteristic is measured by applying a voltage on the side surface of the cylindrical insulator in the sealed space.

  The remaining life diagnosis method of the present invention is characterized in that the remaining life of the cylindrical insulator is diagnosed by measuring the insulation characteristics described above.

  In the present invention, the step of measuring the insulation characteristics before and after cleaning the side surface of the cylindrical insulator, the step of evaluating the reversible deterioration component that can be recovered by the cleaning and the irreversible deterioration component that cannot be recovered by the cleaning, And diagnosing the remaining life in consideration of the cleaning effect based on the evaluation result of the deteriorated component.

  According to the present invention, it is possible to measure insulation characteristics of a cylindrical insulator while keeping it at an arbitrary humidity regardless of the external environment. Further, according to the present invention, it is possible to appropriately measure the insulation characteristics with respect to the side surface of the cylindrical insulator even when the insulator is attached to the site.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram (longitudinal sectional view) of an insulation characteristic measuring apparatus according to a first embodiment of the present invention, and is an explanatory view of an insulation characteristic measuring method. It is a schematic diagram which shows the ring-shaped electrode of this Embodiment. It is a schematic diagram (perspective view) which shows the state which accommodated the insulation insulator as a measuring object in the airtight container of this Embodiment. It is the schematic diagram (longitudinal sectional view cut | disconnected along the BB line shown in FIG. 5 and seen from the arrow direction) of the insulation characteristic measuring apparatus of the 2nd Embodiment of this invention. It is the schematic diagram (cross-sectional view cut | disconnected along the AA line shown in FIG. 4 and seen from the arrow direction) of the insulation characteristic measuring apparatus of the 2nd Embodiment of this invention. It is the schematic diagram (longitudinal sectional view cut | disconnected along the DD line | wire shown in FIG. 7, and seeing from the arrow direction) of the insulation characteristic measuring apparatus of the 3rd Embodiment of this invention. It is the schematic diagram (cross-sectional view cut | disconnected along the CC line shown in FIG. 6 and seen from the arrow direction) of the insulation characteristic measuring apparatus of the 3rd Embodiment of this invention. It is a conceptual diagram of the remaining life diagnostic graph for demonstrating the remaining life diagnostic method of this invention. It is a remaining life diagnostic graph for demonstrating and giving a specific example of the remaining life diagnostic method of this invention.

  Hereinafter, an embodiment of the present invention (hereinafter abbreviated as “embodiment”) will be described in detail. In addition, this invention is not limited to the following embodiment, It can implement by changing variously within the range of the meaning.

  The measurement object of the insulation characteristic in the present invention is, for example, an insulation insulator of a cylindrical insulator that constitutes a high-voltage power receiving and distributing device. High-voltage power distribution equipment is a device in which a high-voltage structure is stored in a board of a certain size. A part having a large potential difference inside the switchboard secures a predetermined insulation strength by increasing a separation distance or sandwiching an insulator. A solid insulator such as a polyester resin or an epoxy resin is used for holding the high-voltage structure or a barrier. When these insulating materials are deteriorated in insulation performance due to aging, they eventually break down. Once dielectric breakdown occurs, it takes time and money to restore the high-voltage power distribution equipment, resulting in a huge social loss.

  The solid insulation has a very high bulk insulation performance that penetrates and breaks down the inside of the insulation, and creeping insulation performance that breaks the insulation surface is a problem.

  Heretofore, it has been known that the surface resistivity of the insulating surface is measured to evaluate the contamination state of the insulating surface based on the measurement result (Patent Document 1). (Especially humidity) has a big influence. For this reason, even if there was no insulation abnormality in the environment at the time of measurement, there was a risk that deterioration would progress due to subsequent exposure to high humidity conditions.

  In addition, conventionally, there is also known a method for estimating insulation characteristics in a high humidity state by measuring a factor not related to humidity (for example, ion amount and color difference), and using a database of insulator deterioration samples and statistical processing. . However, this is merely an estimation of insulation characteristics, and the estimation accuracy cannot be physically guaranteed.

  In addition, for insulating insulators of cylindrical insulators, it is difficult to appropriately measure the insulation characteristics, for example, the metal part is exposed at locations other than the side surfaces. Thus, structurally, it is necessary to measure the insulation characteristics on the side surface for the insulating insulator of the cylindrical insulator.

  Therefore, the present inventor has constructed an insulation characteristic measuring apparatus capable of measuring an insulation characteristic under high humidity with respect to a cylindrical insulator. That is, the first object of the present embodiment is to provide an insulation characteristic measuring apparatus and an insulation characteristic measurement method that can directly measure the insulation characteristic of a cylindrical insulator as a measurement object in a high humidity state without depending on the external environment. Is to provide

  FIG. 1 is a schematic diagram (longitudinal sectional view) of an insulation characteristic measuring apparatus according to a first embodiment of the present invention, and is an explanatory diagram of an insulation characteristic measuring method.

  The X direction, the Y direction, and the Z direction shown in FIG. 1 indicate directions orthogonal to each other, the Z direction is a height direction, and the X direction and the Y direction are two directions constituting a horizontal plane. FIG. 1 shows the insulation characteristic measuring apparatus and the insulation insulator of the present embodiment as a longitudinal section cut along the XZ plane.

  The insulation characteristic measuring apparatus 1 shown in FIG. 1 includes a sealed container 2, a plurality of ring-shaped electrodes 3, 4, humidity adjusting means 5, and connection parts 6, 7. Here, as the measuring means (insulation measuring instrument) 8 for measuring the insulation characteristics, for example, an existing measuring instrument can be used to connect to the connecting portions 6 and 7 later or to change the measuring means 8. . Therefore, the insulation measuring instrument 8 is a configuration necessary for measuring the insulation characteristics, but a configuration (not including the measuring means) including at least the connection portions 6 and 7 for the insulation measuring instrument 8 is the minimum of the insulation characteristic measuring apparatus 1. The insulation measuring instrument 8 is an additional component requirement.

  As shown in FIG. 1, a cylindrical insulator 10 that is a measurement target includes a metal part 11 and an insulating resin part 12. A part of the metal portion 11 appears at the center of the upper surface 10a and the lower surface 10b of the insulating insulator 10 that are substantially parallel to the horizontal plane direction composed of the X direction and the Y direction. On the other hand, the resin portion 12 is exposed on the side surface 10c of the insulating insulator 10. Further, the “cylindrical insulator” in the present embodiment is provided with convex portions such as pleats on the side surface, but in the present embodiment, the curved shape of the side surface is not particularly limited, and FIG. In addition to the insulating insulator shape shown in 3, other insulating insulator shapes are also included in the “cylindrical shape”, and all the surfaces are described as “side surfaces” in convex portions such as folds.

  As shown in FIG. 1, the side surface 10 c is formed with a plurality of convex portions 13 formed along the circumferential direction and spaced in the height direction (Z direction). Therefore, a recess 15 is formed between the plurality of protrusions 13. The convex portion 13 is formed continuously from the upper surface 10a and the lower surface 10b, and includes a pedestal portion 13a disposed on both upper and lower sides of the side surface 10c, and a plurality of pleat portions 13b positioned between the pedestal portions 13a. Configured.

  In addition, each protrusion length (length to the X direction in the longitudinal cross section of FIG. 1) of the base part 13a and the pleat part 13b may be the same, or may differ. Moreover, the depth of each recessed part 15 may be the same, or may differ. Moreover, as shown in FIG. 1, the base part 13a is formed thicker in the Z direction than the pleat part 13b. The pleat 13b is tapered, but the shape is not particularly limited.

  As shown in FIG. 1, each ring-shaped electrode 3 and 4 is attached and fixed in contact with the circumference of a different pleat 13b. Each of the ring electrodes 3 and 4 is not particularly limited as long as it is a conductive material, but is preferably made of a material that does not easily rust because it is in a high humidity state.

  The ring-shaped electrodes 3 and 4 can be clamp-type electrodes as shown in FIG. 2A, for example. In FIG. 2A, the ring-shaped electrodes 3 and 4 are divided into two half ring portions 14 and 15. The half ring portions 14 and 15 are connected at the positions of the rear end portions 14a and 15a, and the front end portions 14b and 15b of the half ring portions 14 and 15 approach or move away from each other with the rear end portions 14a and 15a as the center. It is rotatably supported. Moreover, the fastener 17 is provided in the front-end | tip parts 14b and 15b of each half ring part 14 and 15, By fastening between the front-end | tip parts 14b and 15b of each half ring part 14 and 15 with the fastener 17, Each ring-shaped electrode 3 and 4 can be attached on the front-end | tip periphery of the pleat part 13b. The clamp-type ring electrodes 3 and 4 shown in FIG. 2A can be easily attached to the pleat portions 13b. However, since the diameters of the ring-shaped electrodes 3 and 4 are constant, the diameter of the pleat portions 13b is set. Accordingly, dedicated ring electrodes 3 and 4 are required. Moreover, when the ring-shaped electrodes 3 and 4 are each made of a member having elasticity or stretchability, they can be fixed on the circumference as long as they are in contact at two or more points on the same circumference. In the present embodiment, at least one of the ring-shaped electrodes 3 and 4 can be made of a member having elasticity or stretchability.

  On the other hand, the ring-shaped electrodes 3 and 4 shown in FIG. 2B include a strip-shaped electrode 18 and a binding portion 19. And the front-end | tip of the strip-shaped electrode 18 is passed through the bundling part 19, and the circumferential length of the ring-shaped electrodes 3 and 4 can be adjusted with the length to pass in that case. 2B, the ring-shaped electrodes 3 and 4 can be appropriately mounted on the circumference of the front end of the pleated portion 13b even if the diameter of the pleated portion 13b changes. it can.

  Although not shown, a metal tape may be used as the ring electrodes 3 and 4 instead of the above. Since the length of the metal tape can be adjusted in accordance with the circumferential length of the pleat portion 13b, even if the diameter of the pleat portion 13b changes, the metal tape can be appropriately attached on the circumferential circumference of the pleat portion 13b.

  The ring-shaped electrodes 3 and 4 shown in FIG. 2 are most preferably configured to be arranged over the entire periphery of the pleat portion 13b in order to measure the insulation characteristics of the side surface 10c with high accuracy. Even if the shape is different, almost the same measurement result can be obtained. However, in order to apply a tightening force to the inner periphery, it is preferable that at least one of the ring-shaped electrodes 3 and 4 has a length equal to or greater than a half circumference on the circumference.

  As shown in FIG. 1, each ring-shaped electrode 3, 4 is electrically connected to each connection portion 6, 7 via conductor portions 28, 29. The conductor portions 28 and 29 are cables in which the conductive wire and its periphery are covered with an insulating film.

  The sealed container 2 covers the ring-shaped electrodes 3 and 4 in a non-contact manner, and forms a sealed space 9 between the side surface 10c.

  As shown in FIG. 1, the upper and lower edges 2 a of the sealed container 2 are in contact with and fixed to the surface of the pedestal 13 a through the sealing material 20. Thus, the sealed container 2 is mounted on the outer peripheral curved surface of the insulating insulator 10 and is not in contact with the metal part 11 located on the upper surface 10a and the lower surface 10b. The sealing material 20 is not particularly limited as long as it has a configuration and material that does not allow air to leak out from the sealed space 9 in the sealed container 2. Examples of the sealing material 20 include an elastic body such as rubber. In addition, even if there is no sealing material 20, the sealing material 20 does not need to be provided if it is the structure which can form the sealed space 9 isolated from the exterior by covering the airtight container 2 on the side surface 10c. . Moreover, if the sealed space 9 can be formed without touching the ring-shaped electrodes 3 and 4 and the pleats 13b, the outer shape of the sealed container 2 is not particularly limited. However, as shown in FIG. 2 is preferably cylindrical. Moreover, the airtight container 2 can also be made into the bellows shape which can be expanded-contracted in a height direction (Z direction). Accordingly, by forming the sealed container 2 to expand and contract in accordance with the length of the insulating insulator 10 in the height direction, a sealed space 9 that is appropriately isolated from the outside is formed between the side surface 10c of the insulating insulator 10. Can do.

  However, the sealed space 9 does not mean a strict state that does not allow any air to pass between the outside air, and the sealed space 9 is kept at a high humidity with respect to the outside air even if there is a slight gap. I can do it.

  The airtight container 2 shown in FIG. 3 includes openings 2b along the circumference of the pedestal portion 13a of the insulating insulator 10 on both the upper and lower sides (both sides in the Z direction), and the height direction (Z direction) between the upper and lower openings 2b. It consists of a plurality of parts 22 and 23 divided into two parts. A plurality of parts 22 and 23 are combined from the lateral direction (direction orthogonal to the Z direction) facing the circumferentially curved side surface 10c of the insulating insulator 10 to form a sealed space 9 between the side surface 10c. be able to. In this way, by combining a plurality of parts 22 and 23 from the side facing the side surface 10c of the insulating insulator 10, the sealed container 2 can be attached to the insulating insulator 10 without touching the metal portion 11 of the insulating insulator 10. I can do it.

  The sealed container 2 is formed of a resin material (polypropylene, polyacetal, silicon, etc.), a glass material, stainless steel, or the like, but the material is not particularly limited. However, it is preferable that the container 2 is an insulating material that is not easily deteriorated, such as hardly rusted even when exposed to a high humidity state.

  As shown in FIG. 1, the humidity adjusting means 5 seals the humidifier 23, the air tube 24 as an inflow channel for allowing the humidified air from the humidifier 23 to flow into the sealed space 9 of the sealed container 2, and the humidified air. And an air tube 25 serving as an outflow passage for flowing out from the sealed space 9 of the container 2 to the humidifying device 23. The flow path is not limited in terms of material, thickness, tube shape, or the like as long as the flow path is tubular such as an air tube or an air duct.

  The humidity adjusting means 5 is for keeping the sealed space 9 at a constant humidity. Generally, it is used to keep the sealed space 9 at a higher humidity than the outside air of the sealed container 2. However, when there is a risk of condensation such as when the humidity of the outside air of the sealed container 2 is close to 100%, dew condensation occurs. It is possible to stabilize at a constant high humidity in a range where no occurrence occurs. Here, “constant” does not mean strictly constant but is a concept including a measurement error and the like.

  The humidifier 23 shown in FIG. 1 preferably has a configuration in which a saturated salt solution 26 having a predetermined equilibrium humidity is stored in a solution tank 27. Since the relationship between the type of the saturated salt solution 26 and the temperature in the solution tank 27 and the relative humidity of the air in equilibrium is defined in JIS B7920: 2000, the type and temperature of the saturated salt solution 26 are specified. High humidity constant humidity air can be generated by the humidifier 23, and constant humidity air can be sent from the humidifier 23 to the sealed space 9 of the sealed container 2. For the saturated salt solution 26, for example, potassium sulfate, potassium chloride, sodium bromide, potassium carbonate and magnesium chloride are selected, and the temperature in the solution tank 27 is selected as 10 ° C, 20 ° C, 30 ° C and 40 ° C. With these combinations, it is possible to generate a constant humidity from about 31% to about 99%. When such a saturated salt solution 26 is used, humidified air is circulated through the air tubes 24 and 25 between the humidifying device 23 and the sealed container 2 for several minutes until the humidity becomes constant. Measure the insulation characteristics. In the saturated salt method using the saturated salt solution 26, since constant humidity air can be generated, it is not necessary to provide a hygrometer.

  In the configuration using the saturated salt solution 26 in the humidifier 23 as shown in FIG. 1, it is necessary to configure the saturated salt solution 26 so that it does not flow through the air tube 24 to the sealed space 9 of the sealed container 2. is there.

  Alternatively, a humidity sensor (hygrometer) (not shown) can be attached to each of the air tubes 24 and 25. Then, the humidified air generated by the humidifier 23 is made to flow in and out through the air tubes 24 and 25, and when each humidity sensor has a constant humidity, it is considered that the humidity in the sealed space 9 has become constant. And measure the insulation characteristics.

  In the present embodiment, the configuration of the humidifying device 23 is not particularly limited, but the configuration using the saturated salt solution 26 shown in FIG. 1 can generate constant humidity air, so that a humidity sensor is particularly necessary. And not. Therefore, the configuration using the humidity sensor described above is preferably applied when the humidifying device 23 is configured using something other than the saturated salt solution 26.

  However, in the configuration in which water vapor is discharged from the humidifying device 23, there is a risk that condensation will occur if the average humidity is high, and the humidity in the sealed container 2 is kept constant when the relative humidity becomes higher than about 85%. It is not easy. Therefore, as shown in FIG. 1, it is preferable that the humidifier 23 has the saturated salt solution 26 because it can stably generate constant humidity air and there is no risk of condensation.

  As shown in FIG. 1, the ends of the air tubes 24 and 25 on the side of the sealed container 2 are attached to an air valve 21 that penetrates the sealed container 2 in the direction of the sealed space 9. The air valve 21 is configured as a flow path unit for connecting the air tubes 24 and 25. In the configuration in which the air tubes 24 and 25 are directly inserted into the sealed container 2 and inserted, humid air leakage easily occurs from the inserted portion. Therefore, by providing the air valve 21 integrally with the airtight container 2 and coupling the air tubes 24 and 25 to the air valve 21, the constant humidity air leakage from the airtight container 2 can be appropriately suppressed. The air valve 21 can adjust the amount of air, but the flow path portion that penetrates the sealed container 2 may be a joint or the like instead of the air valve 21.

  As shown in FIG. 1, a circulation pump 32 is attached to an air tube 25 on the air outflow path side from the sealed container 2 to the humidifier 23. By the operation of the circulation pump 32, constant humidity air can be circulated between the humidifier 23 and the sealed space 9 of the sealed container 2 via the air tubes 24 and 25. At this time, as shown in FIG. 1, the circulation pump 32 is attached to the air tube 25 on the outflow path side (the intake side of the circulation pump 32), so that the inside of the sealed container 2 can be set to a negative pressure, and the constant humidity air is smoothly and stably supplied. It can be circulated between the humidifier 23 and the sealed space 9 of the sealed container 2. Moreover, the sealing effect in the airtight container 2 can also be heightened by the negative pressure in the airtight container 2.

  As shown in FIG. 1, the insulation characteristic measuring apparatus 1 is provided with connecting portions 6 and 7 that connect the insulation measuring instrument 8 and the ring-shaped electrodes 3 and 4 via cables 30 and 31. Yes. Thereby, each ring-shaped electrode 3 and 4 becomes a structure each connected to the some connection part 6 and 7 which electrically connects the inside of the sealed space 9, and the exterior. Here, the connection portion 6 will be described as a high voltage terminal and the connection portion 7 as a ground terminal.

  For the insulation measuring instrument 8, an existing commercial product can be used. For example, as the insulation measuring instrument 8, a partial discharge measuring device (for example, DAC-PD-7 manufactured by NEC Corporation) can be used.

  As shown in FIG. 1, the high voltage terminal 6 and the ground terminal 7 penetrate at the position of the sealed container 2 and are fixed in contact with the sealed container 2. Thus, the high voltage terminal 6 and the ground terminal 7 are integrally provided in the sealed container 2. Further, as shown in FIG. 1, the high voltage terminal 6 and the ground terminal 7 are disposed on the opposite sides via an insulating insulator 10. In FIG. 1, the high voltage terminal 6 is located on the left side of the insulating insulator 10 and the ground terminal 7 is located on the right side of the insulating insulator 10. Further, as shown in FIG. 1, the high voltage terminal 6 is located above the position facing the ring-shaped electrode 3 located on the upper surface 10a side of the insulating insulator 10, while the ground terminal 7 is insulated. 10 is located below the position facing the ring-shaped electrode 4 located on the lower surface 10b side. Thereby, the distance H1 in the height direction (Z direction) between the high voltage terminal 6 and the ground terminal 7 becomes larger than the distance H2 in the height direction (Z direction) between the ring electrodes 3 and 4. Yes. Thereby, the terminals 6 and 7 can be arranged at positions where the creeping distance of the inner surface of the sealed container 2 is as far as possible, and the insulating characteristics of the inner surface of the sealed container 2 are made as high as possible than the insulating characteristics of the side surface 10c to be measured. Can do. For example, the creepage distance between the terminals 6 and 7 is preferably set to be twice or more the creepage distance of the side surface 10c between the ring electrodes 3 and 5. As a result, when a high voltage is applied between the ring-shaped electrodes 3 and 4, it is possible to suppress as much as possible the problem of current flowing through the sealed container 2 and to measure the insulation characteristics more appropriately.

  Further, as shown in FIG. 1, the air valves 21 are disposed on the opposite sides of the insulating insulator 10 with respect to each other. Further, as shown in FIG. 1, the air valve 21 disposed on the left side of the insulating insulator 10 in the drawing is disposed below, and the air valve 21 disposed on the right side of the insulating insulator 10 is disposed on the upper side. The valves 21 are arranged in a direction away from each other in the height direction (Z direction) from the lateral direction (X direction). Thereby, the distance in the sealed space 9 of the air valve 21 is separated as much as possible, and high-humidity air can be circulated as efficiently as possible. It is preferable that the air inlet / outlet of the air valve 21 does not face the ring electrodes 3 and 4 so that the high humidity air is not directly blown onto the ring electrodes 3 and 4. As shown in FIG. 1, one air valve 21 is mounted further above the ring-shaped electrode 3 mounted above the insulating insulator 10, and the other air valve 21 is mounted below the insulating insulator 10. The ring-shaped electrode 3 is attached further below, so that the distance between the air valves 21 is increased, and the air inflow / outflow port of the air valve 21 is not opposed to the ring-shaped electrodes 3 and 4. Yes.

  Next, a method for measuring insulation characteristics will be described. The object to be measured in the present embodiment is an insulating insulator 10 that is a cylindrical insulator. First, the ring-shaped electrodes 3 and 4 are attached and fixed on the circumferences of the tips of different pleats 13b formed on the side surface 10c of the insulating insulator 10. At this time, the ring-shaped electrodes 3 and 4 can be attached on the circumference of the pedestal portion 13a. However, the magnitude of the voltage of the transmission / distribution line is regulated by the number of the pleat portions 13b of the insulation insulator 10, and therefore, the insulation characteristics between the pleat portions 13b are important in determining the life. Therefore, it is preferable to attach each ring-shaped electrode 3 and 4 on the front-end | tip periphery of the pleat part 13b.

  Subsequently, the ring-shaped electrodes 3, 4 are covered with the sealed container 2 in a non-contact manner, and a sealed space 9 is formed between the side surface 10 c of the insulating insulator 10 and the sealed container 2.

  Subsequently, the humidifier 23 is operated. In FIG. 1, a saturated salt solution 26 is used, and constant humidity air can be generated by the humidifier 23. The constant-humidity air circulates repeatedly through the humidifier 23 and the sealed space 9 of the sealed container 2 through the air tubes 24 and 25 by the action of the circulation pump 32 in order. At first, since the humidity of the constant humidity air generated from the saturated salt solution 26 is slightly unstable, after circulating for about several minutes (for example, about 3 to 5 minutes), the process proceeds to the next measurement of insulation characteristics. It is preferable. Thereby, the inside of the sealed container 2 is maintained in a constant high humidity state. The constant high humidity state is a state in which the humidity is kept higher than the outside air of the sealed container 2. As described above, by using the saturated salt solution 26, according to JIS B7920: 2000, it is possible to generate high-humidity constant humidity air of about 31% to about 99%. For example, the relative humidity is determined to be 97% for potassium sulfate and 85% for potassium chloride.

  In a state where the humidity of the sealed space 9 is constant, as shown in FIG. 1, an arbitrary insulation measuring device 8 is attached to the high voltage terminal 6 and the ground terminal 7 to acquire the insulation characteristics. Here, the insulation measuring instrument 8 may be attached to the high voltage terminal 6 and the ground terminal 7 in advance before operating the humidifier 23 or before the humidity of the sealed space 9 becomes constant.

  Here, the insulation characteristics include an insulation resistance, a partial discharge voltage, a dielectric breakdown voltage, and the like, and each has a different measurement device and measurement method. For the insulation resistance, a predetermined DC voltage (for example, 25 to 2000 V) is applied to the high voltage terminal 6 and the insulation resistance value is calculated from the current flowing through the ground terminal 7. Specifically, the insulation resistance value in a high humidity state can be measured by directly attaching a commercially available megger to the insulation characteristic measuring apparatus 1 of the present embodiment.

  The partial discharge voltage is measured by applying an AC voltage to the high voltage terminal 6, increasing the voltage until the partial discharge current is detected on the ground terminal 7 side, and evaluating the voltage at which the partial discharge current is detected as the partial discharge voltage. . Specifically, a partial discharge voltage value in a high humidity state can be obtained by directly attaching a commercially available partial discharge measurement device (for example, DAC-PD-7 manufactured by NEC Corporation) to the insulation characteristic measurement device 1 of the present embodiment. It can be measured. Alternatively, as a simple method, a method of determining whether or not partial discharge has occurred by applying an impulse voltage is also conceivable.

  The dielectric breakdown voltage is measured by applying an AC voltage to the high voltage terminal 6 to increase the voltage until dielectric breakdown occurs, and evaluating the voltage at which dielectric breakdown occurs as the dielectric breakdown voltage. Specifically, the dielectric breakdown voltage value in a high humidity state can be measured by directly attaching a high-voltage AC power source to the insulation characteristic measuring apparatus 1 of the present embodiment and causing the dielectric breakdown between the ring electrodes 3 and 4.

  In addition, the insulation characteristic measuring apparatus of this Embodiment can be used for the measurement in the high voltage | pressure of about 3.3 kV or more, for example, in order to measure the insulation characteristic of the insulation site | part in a switchboard. Here, the “high voltage” is not specifically defined as any voltage of V or higher, and all the voltages applied to measure the above-described insulation characteristics are high voltages.

  In the measurement of the insulation characteristics described above, if the humidity is constant, the measurement conditions can be handled as the same even if the temperature changes. For example, when the temperature is 20 ° C. and the humidity is 90%, and when the temperature is 10 ° C. and the humidity is 90%, the insulation characteristics can be measured under the same conditions.

  Further, it is how much the humidity in the sealed container 2 is kept, and this depends on the use conditions of the product including the insulator to be measured. For example, if the use condition is 95% or less, the insulation characteristic is measured by keeping the humidity at the upper limit value of 95%. If the use condition is 85% or less, the insulation characteristic is kept at the humidity value of 85% of the upper limit value. Measure.

  According to the insulation characteristic measuring apparatus 1 of this embodiment and the insulation characteristic measurement method using the same, the insulation characteristic can be measured on the cylindrical insulator after keeping it at an arbitrary humidity regardless of the external environment. It becomes possible. In this embodiment, it is possible to appropriately and easily measure the insulation characteristics of a curved side surface that is not a flat surface. Further, in this embodiment, it is possible to appropriately measure the insulation characteristics even when the insulator is attached to the site, that is, with the insulator 10 shown in FIG. 1 attached to the switchboard. is there.

  FIG. 4 is a schematic diagram (longitudinal sectional view taken along the line BB shown in FIG. 5 and viewed from the direction of the arrow) of the insulation characteristic measuring apparatus according to the second embodiment of the present invention. FIG. 5 is a schematic diagram (a cross-sectional view taken along the line AA shown in FIG. 4 and viewed from the direction of the arrow) of the insulation characteristic measuring apparatus according to the second embodiment of the present invention.

  In the embodiment shown in FIGS. 4 and 5, an insulating sealing film 33 made of a soft material as a sealing member is used instead of the sealed container 2 of the embodiment shown in FIG. 1. Although the material of the sealing film 33 is not particularly limited, it is preferable that the sealing film 33 be a soft insulating material that is not easily deteriorated, such as hardly rusted even when exposed to a high humidity state. For example, examples of the soft material for the sealing film 33 include polyethylene, polyvinyl chloride, and PET. The “soft material” is, for example, a material that is softer than the sealed container 2 shown in FIG. 1 and can be deformed with a relatively weak force. Further, in addition to the case where the material itself is soft, the material itself is softened by thinning.

  The sealing film 33 shown in FIGS. 4 and 5 is placed on the side surface 10c of the insulating insulator 10, and the upper and lower edge portions 33a and 33b of the insulating film 33 are respectively bound on the base portion 13a of the insulating insulator 10 by the binding member 34. Thus, the sealing film 33 is fastened on the circumference of at least two places of the insulating insulator 10. At this time, the sealing film 33 is not in contact with the ring-shaped electrodes 3, 4 and the pleats 13 b and is separated from the ring-shaped electrodes 3, 4. 9 can be formed. The binding member 34 is, for example, a binding string.

  As in the embodiment shown in FIG. 4, in order to form the sealed space 9 without using the sealing film 33 made of a soft material in particular and contacting the sealing film 33 with the ring-shaped electrodes 3 and 4 and the pleats 13b. In addition, it is preferable to provide a spacer 35 between the side surface 10 c of the insulating insulator 10 and the sealing film 33.

  Although the position where the spacer 35 is provided is not particularly limited, the spacer 35 is disposed on the circumference of the pedestal portion 13a of the insulating insulator 10 located on both sides of the upper and lower sides between the ring electrodes 3 and 4. It is preferable. Thereby, the sealed space 9 can be appropriately formed between the side face 10c of the insulating insulator 10 without interfering with the installation of the ring-shaped electrodes 3 and 4. Although the material of the spacer 35 is not limited, the spacer 35 is insulative, hardly rusts even in a high humidity state, and has a rigidity capable of retaining the spacer shape when the sealing film 33 is bound by the binding member 34. Yes.

  As shown in FIG. 5, a plurality of spacers 35 are arranged on the circumference of the pedestal portion 13a with a predetermined interval. At this time, each spacer 35 is formed in a rectangular shape as shown in FIG. 5, for example.

  As shown in FIG. 5, the spacers 35 are connected by a binding band 36. The binding band 36 is passed through a through-hole provided in each spacer 35. By adjusting the length of the binding band 36, each spacer 35 can be tightened in a state of being held at a predetermined position on the base portion 13a. As described above, the plurality of spacers 35 are attached to the insulating insulator 10 with the binding band 36, so that even if the diameter of the insulating insulator 10 changes, the plurality of spacers 35 are attached to the insulating insulator 10 according to the diameter. I can do it. Alternatively, for example, the spacer 35 can be formed by a clamp type in accordance with FIG. 2A, but at this time, a spacer 35 corresponding to each diameter of the insulating insulator 10 is required.

  Although the number of the spacers 35 is not limited, it is preferably 3 or more. As shown in FIG. 4 and FIG. 5, if the number of the spacers 35 is four, the installation is easy and the sealed space 9 can be formed stably.

  As shown in FIGS. 4 and 5, the binding band 36 is passed through a through hole provided in the vicinity of the inner edge of the spacer 35 near the side surface 10 c of the insulating insulator 10. On the other hand, a concave groove is provided on the outer edge of the spacer 35 on the side away from the side surface 10c, and a string-like beam portion 37 is passed through the concave groove. As shown in FIG. 5, the beam portion 37 is held in an annular shape that is wound around the concave groove of each spacer 35. For this reason, the beam portion 37 is formed of an insulating material that can retain its shape when rounded into an annular shape.

  Further, as shown in FIG. 4, the thickness cross sections of the ring-shaped electrodes 3 and 4 are flat unlike the ring-shaped electrodes 3 and 4 shown in FIG. By making the thickness cross section of the ring-shaped electrodes 3 and 4 into a flat plate shape, it can arrange | position stably on the front-end | tip periphery of the pleat part 13b. That is, when the thickness cross-section as shown in FIG. 1 is circular, the ring-shaped electrodes 3 and 4 are likely to be displaced in the direction of the concave portion 15 from the circumference of the tip of the pleated portion 13b. Problems can be suppressed, and the insulation characteristics between the pleat portions 13b can be stably measured. The ring-shaped electrodes 3 and 4 of either the clamp type of FIG. 2A or the bundling type of FIG. The thickness cross section of the ring-shaped electrodes 3 and 4 is not limited to a flat plate shape. For example, a more stable measurement is possible by making the V-shaped or U-shaped according to the shape of the pleat portion 13b. Become.

  FIG. 6 is a schematic diagram (longitudinal sectional view cut along the line DD shown in FIG. 7 and viewed from the direction of the arrow) of the insulation characteristic measuring apparatus according to the third embodiment of the present invention. FIG. 7 is a schematic diagram (cross-sectional view taken along the line CC shown in FIG. 6 and viewed from the direction of the arrow) of the insulation characteristic measuring apparatus according to the third embodiment of the present invention.

  The embodiment shown in FIGS. 6 and 7 is obtained by changing a part of the embodiment shown in FIGS. 4 and 5. Unlike FIGS. 4 and 5, the terminals 6 and 7 are arranged at the positions of the spacers 35. And the air valve 21 is inserted. The terminals 6 and 7 and the air valve 21 penetrate the sealing film 33, and the terminals 6 and 7 are sealed between the sealing film 33 by a sealing material 40 such as a rubber ring in the through portions provided at the upper and lower ends of the sealing film 33. The space between the air valve 21 and the sealing film 33 is sealed.

  Thus, the terminals 6 and 7 and the air valve 21 can be stably held by the spacer 35, and this is particularly effective when the sealing member is a soft material such as the sealing film 33. Further, by passing each terminal 6, 7 through the spacer 35, the distance between the high voltage terminal 6 and the ground terminal 7 can be sufficiently separated. As a result, when measuring the insulation characteristics by applying a high voltage between the ring-shaped electrodes 3 and 4, it is possible to suppress as much as possible a problem of current flowing through the sealing film 33, and to measure the insulation characteristics more appropriately. I can do it. In the present embodiment, at least one of the terminals 6 and 7 and the air valve 21 can be inserted through the spacer 35.

  4 and 5, the upper and lower edges 33 a and 33 b of the sealing film 33 are fastened at the position of the pedestal 13 a of the insulating insulator 10, so that the sealing film 33 contacts the metal part 11. You can avoid the situation.

  In the insulation characteristic measuring apparatus described above, the measuring means 8 is provided outside the sealed space 9. However, the measuring means 8 may be provided inside the sealed space 9. At this time, the terminals 6 and 7 are also disposed in the sealed space 9.

  In the above embodiment, the number of electrodes and the connecting portion (number of terminals) are two, but may be three or more. At this time, it is preferable that at least two of the plurality of connecting portions are arranged on opposite sides of each other via a cylindrical insulator. Moreover, it is preferable that at least two of the plurality of connection portions are arranged in a direction in which the distance between the terminals is away from the position facing the electrode.

  Next, the remaining life diagnosis method will be described. As described above, by using the insulation characteristic device in this embodiment, it is possible to directly measure the insulation characteristic with respect to the cylindrical insulator in a high humidity state without depending on the external environment. The second object of the present invention is to diagnose the remaining life of the insulator while keeping the inside of the sealed container at a constant humidity.

  Here, the occurrence of discharge can be regarded as an insulation life, but in the past, partial discharge detection was not performed while maintaining a high humidity state, so even if no discharge occurred at the time of diagnosis, the surface resistance decreases. In this state, there was a risk of discharge, and the remaining life could not be diagnosed accurately. Or conventionally, the accuracy of the diagnosed remaining life was unknown.

  Therefore, in the present embodiment, it is possible to perform a remaining life diagnosis with higher accuracy than in the past by using the side surface of the cylindrical insulator as a measurement object while maintaining an arbitrary high humidity state.

  First, as a preliminary preparation for the remaining life diagnosis, the insulation resistance value, partial discharge voltage value, insulation required per unit area of the side surface from the duty of insulation at the rated operation of the product with the cylindrical insulator to be measured The breakdown voltage value is defined as the insulation life value.

  Then, using the insulation characteristic measuring apparatus of the present embodiment, the initial insulation characteristic is acquired before the shipment of the product, and the insulation characteristic is measured at the timing when the periodic maintenance inspection or the like is performed at the operation destination of the product. The measurement method of the insulation characteristic using the insulation characteristic measurement apparatus of the present embodiment is as already described. Note that once the same product is obtained, once the initial insulation characteristics before shipment are obtained, the data can be used as initial data for subsequent products.

FIG. 8 is a conceptual diagram of a remaining life diagnosis graph for explaining the remaining life diagnosis method of the present invention. As shown in FIG. 8, it is obtained using an insulating characteristic measuring apparatus of this embodiment the initial value A ₀ of the insulating properties at the time of shipment. At the time of shipment, the lower limit value (insulation life line) of the insulation characteristic that generates discharge at the nominal voltage is acquired.

Next, at the time of measurement after an arbitrary period of time has elapsed after shipment (as in the case of periodic maintenance and inspection as described above), the insulator as a measurement target is not particularly cleaned (in an uncleaned state) obtaining measured current measured value of (uncleaned) a ₁ insulating properties of an insulating characteristic measuring apparatus of this embodiment. If it is assumed that cleaning is not performed after that, the position T ₁ where the remaining life estimation line C ₁ derived from the initial value A ₀ and the current measured value (uncleaned) A ₁ intersects the insulation life line is diagnosed as the life. Can do. Note that although the residual life estimation line C ₁ is not always approximated by straight lines, graphed as approximate curve conforming to the actual physical phenomenon in view of the adhesion material and surface deterioration state. The life time is the year when the remaining life estimation line reaches the insulation life line, and the time from the measurement time to the life time is evaluated as the remaining life. The remaining life estimation line is not expected to be linearized. Regardless of whether or not cleaning will be described later, for example, even if the deterioration progresses at the same speed, the influence on the insulation characteristics is not constant. This is because the numerical variation of the insulation characteristics becomes smaller as the degree of deterioration progresses. Further, although a specific method for calculating the remaining life estimation line will be described later, for example, it can be estimated from the inclination of the two most recent measurement points, or can be estimated from three or more approximate lines or curves. .

  By using the insulation characteristic measuring apparatus of the present embodiment, when measuring the insulation characteristic for a cylindrical insulator as a measurement target, the insulation characteristic is adjusted in accordance with the use conditions of the product having the insulator. Can be measured. That is, if the use condition is 95% or less, the insulation characteristic is measured while maintaining the humidity at the upper limit of 95%. On the other hand, in the past, the insulation characteristics were not measured while maintaining the upper limit humidity under the usage conditions. Could not be judged properly. Or, conventionally, the remaining life was only estimated from the database. On the other hand, in the present embodiment, since it is possible to actually measure the insulation characteristics while maintaining the upper limit humidity under the use conditions, it is possible to perform a remaining life diagnosis with higher accuracy than in the past. Is possible.

  By the way, when the humidity condition is fixed, the reduction factor of the side resistance is limited to the fouling deposit and the base material alteration. The fouling deposit is a reversible deterioration component that can be removed by side cleaning, and the base material alteration is an irreversible deterioration component that is a chemical reaction product generated on the resin surface and cannot be removed by cleaning. When the base material changes in quality, the surface resistance decreases and heat is generated due to leakage current, so that the insulation deterioration reaction progresses. In this embodiment, the cleaning method is not limited. For example, wiping or blowing of the side surface is common. Cleaning also includes the concept of cleaning.

  Therefore, as a step at the time of current measurement after shipment, the insulation characteristic in the uncleaned state is measured as described above, and the insulation characteristic after cleaning is also measured. As described above, since the fouling deposits are classified as reversible deterioration that can be removed, if the fouling deposits can be removed by cleaning, the insulating characteristics can be recovered to some extent.

In the remaining life diagnosis method shown in FIG. 8, after the side surface is cleaned, the insulation characteristic of the cleaned side surface is measured using the insulation characteristic measuring apparatus of the present embodiment. At that time, the insulation characteristics are measured in a state where the humidity is adjusted in accordance with the use conditions of the product having the cylindrical insulator as the measurement object. Thereby current measured value of the insulating characteristics give (after cleaning) A _2. As shown in FIG. 8, the product is periodically cleaned, and the insulation characteristics before and after the side surface cleaning are measured each time. As shown in FIG. 8, it can be seen that the measured value obtained shifts before and after cleaning with respect to the remaining life estimation line C ₁ obtained when cleaning is not performed at all. It can also be seen that the insulation life line is approaching. This is because the insulating characteristics include a reversible deterioration component that can be recovered by cleaning and an irreversible deterioration component that cannot be recovered by cleaning. Note that the insulation characteristics before and after cleaning are measured at the time of measurement.For example, even if only the insulation characteristics after cleaning are measured, there are reversible deterioration components that can be recovered by cleaning and irreversible deterioration components that cannot be recovered by cleaning. This is because it is not possible to appropriately evaluate how much it exists and how it changes thereafter, and it is not possible to produce a highly accurate remaining life estimation line.

That is, in this embodiment, the remaining life based on the evaluation of both the reversible deterioration component that can be recovered by cleaning and the irreversible deterioration component that cannot be recovered by cleaning, and the evaluation results of these deterioration components and a step of diagnosing the prepared remaining lifetime estimation line C _2. Thus, it is possible to obtain a highly accurate remaining service life estimation line C _2.

  Thus, according to the remaining life diagnosis method of the present embodiment, the remaining life including the cleaning effect can be diagnosed. In addition, by taking into account the recovery of insulation performance through cleaning, it is possible to determine the remaining life more finely than before, and it is possible to accurately diagnose how much life can be extended, so it is possible to determine in advance when to replace the product in advance It is easy to do this, and it is possible to appropriately plan a cleaning management plan to extend the life.

The remaining life diagnosis method in the present embodiment will be described more specifically. First, as an advance preparation at the time of shipment, an initial value ρ ₀ of the surface resistivity under high humidity with respect to the target insulator and a use lower limit value ρ _n at which discharge occurs at a nominal voltage are acquired.

Subsequently, after the product including the insulator is shipped, on-site measurement is performed. In FIG. 9, for example, it was assumed that field measurements were made after 15 years. In the field measurement, the value before cleaning ρ _1a and the value after cleaning ρ _1b under high humidity are measured in order to reflect the cleaning effect. The remaining life estimation line using these values is shown in FIG.

When cleaning was impossible, it was assumed that time elapsed, fouling accumulation amount, equivalent salt adhesion density, surface conductivity at high humidity = 1 / surface resistivity, and surface resistance continued to decrease uniformly. Since there is a lower limit to the surface resistivity is fouling test, using equation (1) below as a relational expression of the elapsed time t and the surface resistivity [rho _a when not cleaning.
ρ _a (t) = A / t ^α (1)

In equation (1), the fitting coefficient α can be obtained from ρ _a (1) = ρ ₀ to A = ρ ₀ and ρ _a (t ₁ ) = ρ _1a .

The remaining life years during uncleaned putting a _{t ra,} can be calculated from _{ρ a (t 1 + t ra} ) = ρ remaining life years _{t ra} by solving _n equations (1).

Subsequently, when cleaning is possible, the fouling deposits can be removed by cleaning, and the ρ _1b value shown in FIG. 9 is assumed to be an irreversible decrease in surface resistance due to the base material alteration. The state after this cleaning was set as a new initial state, and it was thought that the surface resistance would continue to decrease due to fouling deposits in the same trend as before. Therefore, the equation (2) below the relationship of the elapsed time t and the surface resistivity [rho _b after cleaning the above equation (1) as a base.
ρ _b (t) = ρ _1b / (t−t ₁ ) ^α (2)

The α value of the equation (2) is the same as that of the equation (1), and the life time t _rb after cleaning can be calculated by solving for ρ _b (t ₁ + t _rb ) = ρ _n .

From the above, it has been found that for equipment that can be cleaned, it is possible to plan to extend the equipment life by implementing equipment cleaning before reaching the remaining life years _trb .

  According to the insulating property measuring apparatus of the present invention, the insulating property of the side surface can be measured while keeping the side surface of the cylindrical insulator at an arbitrary humidity regardless of the external environment. And by using the insulation characteristic measuring device of the present invention for power distribution facilities that have the need to operate the existing facilities for as long as possible, the remaining life diagnosis can be performed accurately and appropriate updates that do not cause failures It becomes possible to determine the time.

DESCRIPTION OF SYMBOLS 1 Insulation characteristic measuring apparatus 2 Sealed container 3, 4 Ring-shaped electrode 5 Humidity adjustment means 6 Connection part (high voltage terminal)
7 Connection (grounding terminal)
8 Measuring means (insulation measuring instrument)
DESCRIPTION OF SYMBOLS 9 Sealed space 10c Side surface 11 Metal part 12 Resin part 13a Pedestal part 13b Folding part 20, 40 Sealing material 21 Air valve 23 Humidifier 24, 25 Air tube 32 Circulation pump 33 Sealing film 34 Binding member 35 Spacer 36 Binding band 37 Beam Part

Claims (12)

An insulation characteristic measuring device for measuring the insulation characteristic of a cylindrical insulator,
A plurality of electrodes arranged at intervals on a side surface of the cylindrical insulator;
A sealing member that covers the plurality of electrodes and can form a sealed space isolated from the outside;
Humidity adjusting means capable of maintaining the sealed space at a constant humidity;
A connecting portion for connecting a measuring means for measuring the insulating characteristic of the cylindrical insulator by applying a voltage between the plurality of electrodes,
An insulation characteristic measuring apparatus comprising:   The insulation characteristic measuring apparatus according to claim 1, wherein each of the plurality of electrodes is disposed on different circumferences of the cylindrical insulator.   The insulation characteristic measuring apparatus according to claim 2, wherein at least one of the plurality of electrodes contacts at two or more points on the same circumference of the cylindrical insulator.   The insulation characteristic measuring apparatus according to claim 3, wherein at least one of the plurality of electrodes is provided over a half circumference on the same circumference of the cylindrical insulator.   The sealing member is formed of a soft material, and the sealing space is configured such that the sealing member is clamped on at least two circumferences of the cylindrical insulator and includes the plurality of electrodes therein. The insulation characteristic measuring apparatus according to claim 1, wherein the insulating characteristic measuring apparatus is formed.   The insulation characteristic measuring apparatus according to any one of claims 1 to 5, further comprising a spacer interposed between a side surface of the cylindrical insulator and the sealing member to maintain the sealed space.   7. The spacer according to claim 6, wherein at least one of flow path portions for circulating air between the connection portion, the humidity adjusting means and the sealed space is inserted into the spacer. Insulation characteristic measuring device.   The plurality of electrodes are respectively connected to the plurality of connection portions that electrically connect the inside and the outside of the sealed space, and at least two of the plurality of connection portions are mutually connected via the cylindrical insulator. The insulating characteristic measuring apparatus according to claim 1, wherein the insulating characteristic measuring apparatus is disposed on the opposite side.   The insulation characteristic measuring apparatus according to claim 8, wherein at least two of the plurality of connecting portions are arranged in a direction in which a distance between the connecting portions is away from a position facing the electrode. A method for measuring insulation properties for a cylindrical insulator comprising:
Forming a sealed space on the side surface of the cylindrical insulator;
Adjust the inside of the sealed space to a constant humidity,
A method for measuring an insulation characteristic, wherein a voltage is applied to the side surface of the cylindrical insulator in the sealed space to measure the insulation characteristic.   A remaining life diagnosis method characterized by diagnosing the remaining life of the cylindrical insulator by measuring the insulation characteristic according to claim 10. Measuring the insulating properties of the cylindrical insulator side surface before and after cleaning, evaluating the reversible deterioration component recoverable by the cleaning and the irreversible deterioration component unrecoverable by the cleaning, and The remaining life diagnosis method according to claim 11, further comprising a step of diagnosing a remaining life in consideration of an effect of the cleaning based on an evaluation result.

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