JPH09145558A - Method for collecting sample for diagnosis of heat deterioration of winding insulation of rotary machine by instrumental analysis - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for easily collecting a sample from a winding insulation inside a rotary machine without pulling out a rotor from the rotary machine when sampling for diagnosing a heat deterioration by instrumental analysis. SOLUTION: A sample-collecting device consists of a supporting jig which supports an internal observation jig 4 of a fiberscope 3 for observing a winding inside a rotary machine, a cutting jig 6 having a drill 5 for cutting a winding insulation material from a surface layer of the winding, and a trapping jig 8 of a suction hose 7 for trapping the cut sample. The supporting jig is mounted on a supporting plate 15. The collecting device is inserted between a rotor and a stator of the rotary machine thereby to cut the sample by the drill 5 from the insulating surface layer of the winding. The sample is trapped by the suction hose 7 into a trapping bag 13 of a trapping device 14 outside the rotary machine.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for collecting a sample for insulation from electrical equipment, in particular, in the case of performing thermal deterioration diagnosis of a winding insulation material of a rotating machine by equipment analysis.

[0002]

2. Description of the Related Art Conventionally, electrical characteristic tests such as insulation resistance, partial discharge, and dielectric loss tangent of windings have been generally performed as a diagnosis of deterioration of winding insulation of a rotating machine. However, in the above-mentioned electric characteristic test, mainly the diagnosis of the winding insulating layer of the iron core slot portion is targeted, and it is difficult to directly estimate the deterioration of the insulating material forming the winding. Therefore, to determine the degree of thermal deterioration of the insulating material due to heating of the winding during long-term operation, for example, the main insulating material of the coil insulating layer portion and the sub-insulation such as wedges, spacing pieces, binding strings, etc. in contact with the coil are used. It is necessary to collect a sample for evaluation directly from the material and diagnose the thermal deterioration from the mechanical characteristics.

However, in the diagnostic test based on the above-mentioned mechanical characteristics and the like, the stator of the rotating machine or the coil of the rotor is disassembled and a test piece of several cm size is sampled from the target coil winding by machining. It is necessary to do so, the work of sampling becomes large, and the diagnostic cost becomes high. In addition, there is a problem in that the sampling is taken from the above-mentioned winding, which may damage the winding insulation and impair accurate diagnosis. Further, since the above-mentioned test piece is sampled from the target insulating material so as to have a predetermined size and is taken out, the characteristics of the outer coating layer which is in contact with the atmosphere and has large oxidative deterioration are oxidative deterioration. There is a possibility that accurate information may not be obtained due to the characteristics of the inner layer that have not been received.

Therefore, as a method for diagnosing thermal deterioration of an insulating material, a decrease in mechanical strength and an increase in heat loss due to thermal deterioration of the insulating material are correlated with the degree of physicochemical change of the material. Thermal Degradation Analysis of Insulation Materials "(The Institute of Electrical Engineers of Japan
So-called instrumental analysis using instruments such as thermal analysis (TG-DSC analysis) and infrared spectroscopic analysis (IR analysis) as described in the rotating machine research group material RM-95-32 March 10, 1995). The application of the thermal deterioration diagnosis method by is progressing. The diagnostic method by this thermal analysis is that the curve of the weight change of the material and the endothermic exothermic characteristics of the sample that occur when heated at a constant rate, and that by the infrared spectrophotometer the specific molecule (for example, carbonyl group) that constitutes the material. Since the change in the absorption spectrum of) has a correlation with the degree of heat deterioration, the mechanical strength and heat loss obtained from the heat-deteriorated material in which the material is accelerated and deteriorated by heating in advance, and the characteristics obtained by the above-mentioned device analysis A master curve representing the correlation with is obtained in advance, and the degree of thermal deterioration of the diagnostic material is diagnosed from this.

In the diagnosis of the degree of thermal deterioration of the insulating material by the above-mentioned instrumental analysis of thermal analysis and infrared spectroscopic analysis, it is sufficient that the sample to be tested is about several hundred mmg, and the surface of the target winding is sanded or the like. Can be done with almost no damage to the winding insulation. In addition, there is an advantage that the thermally deteriorated material can be directly diagnosed and the time required for the diagnosis can be determined more quickly than the conventional method.

[0006]

By the way, when the above-mentioned thermal deterioration diagnosis of the winding insulation of the rotating machine is conducted by the equipment analysis, a very small amount of the sample is taken from the insulating material of the winding to be diagnosed as described above. However, it is not possible to take a sample directly from the coil winding insulation layer located inside the rotating machine because the gap between the stator of the rotating machine and the rotor is narrow, and the test sample cannot be taken from the conventional winding insulation described above. In the same manner as in the case of sampling, the rotor of the heavy object needs to be taken out of the rotating machine and collected from the surface of the main insulating layer of the target coil and the auxiliary insulating material such as wedges and spacing pieces. Therefore, there is a problem in that it takes a lot of time to collect the sample and the operation cost is high.

An object of the present invention is to solve the above-mentioned problems and to collect a sample for heat deterioration diagnosis for equipment analysis from the winding insulation of a rotating machine without easily pulling out the rotor from the rotating machine. It is to provide a sampling method capable of collecting the.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a sampling method for diagnosing thermal deterioration of winding insulation of a rotating machine by device analysis. A sample equipped with a fiberscope for observing the wire, and a cutting jig for cutting the winding insulating material from the surface layer of the rotating machine winding at the tip and a collecting jig for collecting the cut sample The sampling device is inserted between the rotor and the stator of the rotating machine so that a sample is collected from the target portion of the rotating machine winding. As a result, a sample can be taken from the winding insulation of the rotating machine without pulling out the rotor, so that it is possible to significantly reduce the number of man-hours required for taking the sample as compared with the conventional case.

A method of mounting the above-mentioned sample collecting device on a flexible long supporting plate and inserting the sample collecting device into a predetermined sample collecting position while observing the inside of the rotating machine with a fiberscope. By adopting, it becomes possible to easily reach a portion which cannot be observed from the outside by operating the above-mentioned flexible long plate, and a sample for testing can be collected.

Further, a cutting jig for cutting and collecting a sample from the winding insulating surface is collected by using a rotary drill or the like, and the cut sample is collected by an aspirator provided outside the rotating machine. If this is done, the time required to collect the sample can be further shortened.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. Embodiment 1 FIGS. 1 and 2 show a method of sampling a rotary machine winding insulation showing a first embodiment of the present invention. FIG. 1 is a sectional view of a coil winding of a generator and a sample. FIG. 2 is an explanatory view of the sampling device, FIG. 2 is a partial detailed view of the sampling device, (a) is a perspective view, and (b) is a P arrow view of (a). As shown in FIG. 1, the sampling device includes an internal observation jig 4 composed of a fiberscope 3 having a solid-state image sensor composed of a CCD image sensor 2 at the tip of an optical fiber 1, and an insulation constituting a winding insulation. A cutting jig 6 having a spherical drill 5 at the tip for collecting a sample for analysis from the surface layer of the material, and a supplementary collecting jig sucking the sample cut by the cutting jig 6 with a suction hose 7. The part to be inserted into the rotating machine, which is composed of the tool 8, the recording device 9 composed of the video (VTR) provided at the other end of the fiberscope 3 described above, and the drill 5 of the cutting jig 6 are driven by pneumatic power. A drill drive controller 10,
And a part installed on the outside of the rotating machine composed of a collector 14 that collects the sample cut from the collector jig 8 into the collector bag 13 inside the suction device 12 by the suction pump 11. There is.

In the above-mentioned sample collecting device, each jig inserted into the rotating machine of this sample collecting device, the suction hose 7 and wirings connected to each component outside the rotating machine are made of long metal. It is mounted on a support plate 15 made of steel. The support plate 15 is a short support plate 1 as shown in FIG.
5a is connected by a pin 15b, and the support plate 15 can be bent at the pin 15b portion so that each jig of the sampling device can be inserted into the rotating machine and the space between the stator and the rotor. It can be inserted from the section. Further, as shown in FIG. 2, each jig is supported by being inserted in the axial direction of a supporting jig 16 made of a molded product, and the supporting jig 16 is fixed on the support plate 15 and wound. When the sample is taken from the wire insulation, the jigs of the sampling device can be integrally moved. As shown in the figure, the support jig 16 is provided with a recess 17 inside in the axial direction, and the samples cut by the drill 5 are accumulated in the recess 17. Then, the opening of the suction hose 7 of the collecting jig 8 is provided at a position near the partition wall 18 of the concave portion 17 so as to improve the collecting efficiency by sucking the sample in the concave portion 17. .

Next, with the sampling device according to this embodiment, a sample for thermal deterioration diagnosis is analyzed by instrumental analysis of the spacing piece 21 inserted between the coil end portions 20 of the stator coil 19 shown in FIG. The collection procedure will be described below. By investigating the degree of thermal deterioration of the spacing piece 21,
It is possible to diagnose the thermal deterioration of the winding insulation of the coil end portion 20 which is in contact with. First, the insertion position of the support jig 16 supporting each jig of the sample collecting device is set. Before inserting the supporting jig 16 into the rotary machine, the internal condition is confirmed by an observation jig for inspecting the rotary machine, which is separately prepared and includes a fiberscope having a CCD image sensor at the tip. To do. Next, the stator coil 19
Carefully lift the support jig 16 fixed to the tip of the support plate 15 so as not to damage the rotor 22 when inserting the support jig 16 through the gap between the rotor 22 and the rotor 22. Then, the internal peripheral condition imaged by the internal observation jig 4 is advanced to the inside of the rotary machine while the recording device 9 is monitoring, and the support jig 16 of the sampling device is installed at the position of the spacing piece 21. Then, the position of the cutting jig 6 is adjusted while operating the support plate 15 so that the tip of the drill 5 is located at the center of the spacing piece 21. Press the drill 5 against the spacing piece 21,
After the suction pump 11 of the suction device 12 is activated to draw in air from the suction hose 7 or exhaust check, the sample is cut by cutting at about 5 rotations per second for about 30 seconds. It should be noted that at the time of collecting the sample, it is performed while inspecting the sample sucked from the suction hose 7 and collected in the collecting bag 13 of the collector 14.

The sample is sampled at one location per one spacing piece 21, and the sampling amount may be about 100 mg. While the rotor 22 is sequentially rotated and the internal observation jig 4 is used for observation, the sample is taken at another position. The position of the supporting jig 16 is set on the spacing piece 21 in the same manner as described above, and samples are taken from a plurality of locations around the coil end portion 20. Then, the sampling situation of the sample by the above-mentioned sampling apparatus and the inspection situation of the interval piece 21 after the sampling are recorded by the video (VTR) of the recording apparatus 9 provided in the fiberscope 3 of the internal observation jig 4 described above. I will leave it.

For the illumination of the inside of the rotating machine by the CCD image sensor 2, a light guide made of an optical fiber is provided on the fiber scope 3 on the outer periphery of the internal observation jig 4, or a light guide made of an optical fiber alone. Can be performed by guiding the light source from the illumination device from the outside of the rotating machine to the inside of the rotating machine. Further, the rotational driving of the drill 5 of the cutting jig 6 can be performed by electric driving instead of pneumatic driving. Furthermore, although the method of sampling the wedge 21 is described in the first embodiment, since the cross-sectional shape of the support jig 16 of this sampling device is several tens of millimeters and is small, it is located inside the rotating machine shown in FIG. It is also possible to collect a sample from the wedge 24 inserted into the stator core 23, and the heat of the winding insulation forming the stator coil 19 in the stator core 23 in contact with the wedge 24 It is also possible to diagnose the degree of deterioration.

Embodiment 2 FIG. 3 is a partial perspective view of a sampling device showing a second embodiment of the present invention. The difference between the second embodiment and the first embodiment is that the cutting jig for cutting the sample and the collecting jig have different configurations. As shown in FIG. 3, in this embodiment, a cutter 25 is used in place of the cutting jig 6 with the drill 5 shown in FIG. The purpose is to obtain a sample for analysis by cutting out the surface layer of the target winding insulation. And when collecting a sample with this cutter 25,
The cutter 25 is manually or automatically driven from the outside of the rotating machine to perform cutting, and the cut sample is collected by the cutter 2.
The collecting jig 8a is composed of a movable receiving tray 26 which is connected to the end of a support plate 15 which holds a supporting jig 16a which will be described later and which is located below the reference numeral 5 by a pin 161a.

The sample is taken in the same procedure as in the first embodiment, which includes a cutting jig 6a including a cutter 25 and a fiberscope 3 including a CCD image sensor 2 at the tip of the optical fiber 1. A flexible support plate 1 on which a support jig 16a supporting the observation jig 4 is placed.
5 is inserted into the rotating machine, and the opening of the pan 26 is pin 16 so that the sample cut by the cutter 25 can be collected.
It is moved around 1a as an axis so that it can be collected. Then, the sample accumulated in the pan 25 is supported by the support plate 1 from the inside of the rotating machine.
5 is moved and taken out of the rotating machine to be collected.

The sampling method of the winding insulation of the rotating machine by this sampling apparatus can be performed while observing the inside of the rotating machine with the internal observation jig 4 as in the first embodiment. Moreover, there is an advantage that the collector 14 for collecting the sample as in the first embodiment shown in FIG. 1 is not required and the operation method is simple. It should be noted that, including the first embodiment described above, it is possible to use a fiberscope having an objective lens on the normal sampling side for observation of the inside of the rotating machine, but the configuration using the CCD image sensor 2 is ,
It has the feature of being compact and capable of obtaining highly accurate images.

[0019]

As described above, according to the present invention, the sample for analysis of the winding insulation inside the rotating machine, which is required when the thermal deterioration diagnosis of the winding insulation of the rotating machine is performed by the equipment analysis, is not provided. Since it is possible to extract from the coil winding insulation to be diagnosed without pulling out the rotor from the rotating machine like
The number of man-hours required for sampling in the diagnostic test can be significantly reduced, and insulation diagnosis can be performed without fear of impairing the insulation reliability due to damage to the winding insulation during the above-described disassembly and assembly of the rotating machine. Therefore, the diagnostic method by device analysis, which has the feature that the deterioration degree of the material can be directly and quickly determined with a very small amount of sample without damaging the winding insulation, is a It is possible to promote the expansion of application as an insulation diagnosis method and contribute to the improvement of the reliability of the rotating machine winding.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a stator coil winding of a generator showing a first embodiment of the present invention and an explanatory view of a sampling device.

2A and 2B are detailed views of a jig of the sample collecting device, FIG. 2A is a perspective view, and FIG.

FIG. 3 is a perspective view of a jig of a sampling device having a configuration different from that of the first embodiment, showing a second embodiment of the present invention.

[Explanation of symbols]

 1 Optical fiber 3 Fiberscope 4 Internal observation jig 5 Drill 6 Cutting jig 6a Cutting jig 7 Suction hose 8 Collection jig 9 Recording device 10 Drill drive controller 11 Suction pump 12 Suction device 13 Collection bag 15 Support plate 16 Support jig 16a Support jig 25 Cutter 26 Saucepan

Claims (6)

[Claims] Claim: What is claimed is: 1. A sample of a winding insulating material constituting a rotating machine winding is sampled, and the sample is analyzed by instrumental analysis to determine the degree of thermal deterioration of the insulating material. In the sampling method for diagnosis, a fiberscope for observing the winding inside the rotating machine is provided, and a cutting jig for cutting the winding insulating material from the surface layer part of the rotating machine winding at the tip, and the cut sample A rotating machine winding by instrumental analysis, characterized by inserting a sample collecting device having a collecting jig for collecting the sample into a space between a rotor and a stator of a rotating machine to collect a sample from a rotating machine winding. Sampling method for diagnosing thermal deterioration of wire insulation. 2. The sampling method according to claim 1, wherein
The sampling device is placed on a long flexible support plate,
A sampling method for diagnosing thermal deterioration of winding insulation of a rotating machine by instrumental analysis, which comprises inserting a sampling device into a predetermined sampling position while observing the inside of the rotating machine with a fiberscope. 3. The sampling method according to claim 1, wherein
A sampling method for diagnosing thermal deterioration of winding insulation of a rotating machine by device analysis, wherein a cutting jig for cutting the winding insulating material is a rotary drill. 4. The sampling method according to claim 1, wherein
A sampling method for diagnosing thermal deterioration of rotating machine winding insulation by device analysis, wherein a cutting jig for cutting the winding insulating material is a cutter. 5. The sampling method according to claim 1, wherein
The collecting jig for collecting the cut sample is composed of a suction hose that sucks and collects the sample into the collector with a suction device provided outside the rotating machine. Sampling method for diagnosing thermal deterioration of winding insulation of rotating machines by means of equipment analysis. 6. The sampling method according to claim 1, wherein
A collection jig that collects the cut sample is composed of a pan, and the sample collected on the pan is taken out together with the sampling device to the outside of the rotating machine to collect the sample. Sampling method for diagnosing thermal deterioration of wire insulation.