JP2002246252A - Monitoring equipment of transformer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the monitoring equipment of transformers that can accurately monitor the clearance between space and a coil without discharging insulating oil, and can tighten a bolt for mounting spacers at appropriate time furthermore. SOLUTION: The image of the contact surface (contact portion) between a multilayer coil 5 of the transformer 1 and an insulating spacer 6 is picked up by a CCD camera 10a, and image data that are picked up by the CCD camera 10a are processed by an image processor 13 for monitoring the clearance between the coil 5 and insulating spacer 6 by the image of the contact surface between the coil 5 and insulating spacer 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transformer monitoring device for monitoring a gap at a contact surface between a multilayer coil of a transformer installed in an insulating oil and an insulating spacer.

[0002]

2. Description of the Related Art Generally, a transformer installed in a power plant, a substation, or the like is installed in a box in which a multilayer coil and an insulating spacer (insulating paper) are filled with insulating oil. The insulating oil of the transformer is cooled by an attached cooling device, and is controlled so that the transformer is maintained at a predetermined temperature or lower. When insulating oil is used for many years, the insulating property is deteriorated due to heat generation of the coil. If the deterioration is remarkable, the insulating oil is purified and used by deaeration circulation or the like. The transformer has a core made of an electromagnetic steel sheet constituting a magnetic circuit, a multilayer coil fitted around the core and wound multiple times,
It is composed of an insulating spacer or the like sandwiching each layer of the multilayer coil.

In the transformer having such a configuration, the spacer is bolted so that a load is applied from above and below via a pressing plate. However, when the spacer (insulating paper) is used for a long period of time, it shrinks due to aging and a gap is generated on the contact surface with the coil surface. The location of the contact surface gap varies depending on the manufacturing variations, the use environment, particularly the installation location, the use power load condition, etc., even for transformers of the same specification.

[0004] When the gap between the coil surface and the spacer becomes large, electromagnetic noise increases, mechanical force decreases, life decreases, and the like. For this reason, it is necessary to check whether the gap between the coil surface and the spacer is equal to or smaller than a specified value. If the specified value is not satisfied, it is necessary to immediately retighten the bolts to reduce the gap.

Conventionally, the gap between the coil surface and the spacer is removed at every predetermined period empirically determined by stopping the power supply to the transformer to remove the insulating oil. To check the gap.

[0006]

In the prior art, when a power outage is not allowed, a switch to a spare transformer is performed.
Alternatively, there is a problem that it is necessary to switch to another operating transformer and perform the inspection work at a time when there is enough time. In addition, it takes a long time to drain a large amount of insulating oil and fill the insulating oil after checking the gap, which increases the cost.Furthermore, even if there is no problem in checking the gap, the insulating oil is wasted, It is not preferable from the viewpoint of resource saving and environment.

For this reason, there is a demand for the development of a technique capable of quickly measuring the gap between the coil and the spacer without draining the insulating oil.

SUMMARY OF THE INVENTION An object of the present invention is to provide a transformer monitoring apparatus which can accurately monitor a gap between a spacer and a coil without removing insulating oil and can retighten a spacer mounting bolt at an appropriate time. It is in.

[0009]

A feature of the present invention is that an image of a contact surface (contact portion) between a multilayer coil of a transformer and an insulating spacer is taken by a CCD camera, and image data taken by the CCD camera is subjected to image processing. The gap between the coil and the insulating spacer is monitored by an image of the contact surface between the coil and the insulating spacer, which is processed by the apparatus. In the present invention, since the contact surface between the coil and the spacer of the transformer is imaged by a CCD camera and the image data is processed by an image processing device, the gap between the contact surfaces is compared with the image data imaged at the beginning of use of the transformer. Can be monitored.

[0010]

FIG. 1 shows an embodiment of the present invention.

In FIG. 1, a transformer main body 1 includes a core 3 made of a magnetic steel sheet constituting a magnetic circuit, a plurality of coils (multi-layer coils) 5 wound around the outer periphery of the core 3 and having primary and secondary insulated. An insulating spacer 6 mounted in contact with the coil 5 group, a plurality of metal shields 9 provided to avoid concentration of an electric field, a yoke 4 forming a part of a magnetic circuit, and a bolt 8 together with the yoke 4 And a holding plate 7 for holding the spacer 6 from above and below. Usually, several bolts 8 are provided outside the core 3 so that the tightening load is applied to the presser plate 7 and the spacer 6 on average.

The transformer 1 having such a configuration is housed in a box body 2, and its space is filled with insulating oil, and the insulating oil is circulated by a cooling device (not shown). Then, the temperature rise due to the power loss of the transformer 1 is suppressed to a specified value or less.

Reference numeral 10 denotes a lens for a CCD camera (solid-state image pickup device camera), which is hermetically installed on the inner wall of the box 2 in a form integrated with the illuminating lamp 11 together with the image receiving portion 10a, into which insulating oil enters. Lens 10 and image receiving unit 10
a and the lamp 1 are properly sealed. Image receiving unit 1
0a is transmitted to the outside, the connector 12
Are connected in an airtight manner.

Lens 10 for CCD camera, image receiving unit 10
a, a plurality of illuminating lamps 11 are provided so that images can be taken between the spacers 6. FIG. 1 shows an example in which four sets are installed, and each lens is set so that the lens 10 is in focus. In the contact portion between the spacer 6 and the coil 5, there is a gap that does not slightly contact locally due to a manufacturing error of each part, particularly a flatness error. By comparing the measured value with the specified value, a pass / fail judgment is made for the specified value of the gap change amount empirically determined.

Reference numeral 13 denotes an image processing device, which is a CCD camera lens 10 and an image receiving unit 10a sent through a connector 12.
The gap between the coil 5 and the spacer 6 is displayed on the screen on the basis of the image data obtained by the above, and is printed as necessary. CCD
The camera lens 10 is installed at a predetermined position at the time of shipment from the factory, and is fixed at a fixed position during the operation period of the transformer. Therefore, when measuring the gap, the same part is imaged irrespective of the usage period, and the occurrence of a measurement error can be prevented.

If the clearance exceeds the specified value, the insulating oil is drained as before, and an operator enters the inside of the box, and the bolt 8
Tighten.

FIG. 2 is an example showing the results of the gap measurement values.

If the insulating oil of the transformer 1 has been used for many years, the heat generated by the coil 5 will deteriorate the insulating properties. If the deterioration is remarkable, the insulating oil is purified and used by deaeration circulation or the like. However, the components of the transformer 1 are exposed to the deteriorated insulating oil until the oil is refined, and the effect on the increase in the gap between the coil 5 and the spacer 6 is accelerated.

The characteristics shown in FIG. 2 can be arbitrarily displayed on the screen by the image processing apparatus 13. In this example, it is predicted from the result at the lapse of 72 months that the predetermined gap becomes 0.60 mm or more around 90 months or more. it can. For example, when the transformer 1 is installed in an unmanned substation in the mountains, a worker goes to the site, captures image data with a portable personal computer, takes it home, and decodes it with the image processing device 13 installed in the central control room. You can also. Furthermore, it is also possible to set up a personal computer at the site, record it on a floppy disk, take it home, or transmit it to a central control room by wireless communication.

According to the present invention, without removing the insulating oil,
The gap can be measured at an arbitrary time interval as appropriate, and the trend management, that is, the tendency of the increase in the gap can be grasped. Therefore, it is possible to predict the time when the specified gap is reached. And so on.

[0021]

According to the present invention, since the contact surface between the coil of the transformer and the spacer is imaged by the CCD camera and the image data is processed by the image processing apparatus, the image data is compared with the image data imaged at the beginning of use of the transformer. Accordingly, it is possible to monitor the gap between the contact surfaces, and it is possible to retighten bolts or replace parts at an appropriate time regardless of the use period.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of the present invention.

FIG. 2 is a characteristic diagram for explaining the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Transformer 2 ... Box 3 ... Core 4 ... Yoke 5 ... Coil 6 ... Spacer 7 ... Holder plate 8 ... Bolt 9 ... Metal shield 10 ... Lens for CCD camera 10a ... Image receiving part 11 ... Illumination lamp 12 ... Connector 13 ... Image processing device

Claims (2)

[Claims] 1. A transformer in which a multilayer coil having insulating spacers disposed between layers is immersed in insulating oil, a CCD camera for imaging a contact surface between the multilayer coil and the insulating spacer, and an image captured by the CCD camera. An image processing device for inputting data and performing image processing is provided, and a gap between the multilayer coil and the insulating spacer is monitored based on a contact surface image of the multilayer coil and the insulating spacer processed by the image processing device. Transformer monitoring device. 2. An image of a transformer in which an insulating paper is interposed between layers and a multi-layer coil fastened and fixed by bolts is immersed in insulating oil, and a contact surface between the coil surface of all layers of the multi-layer coil and the insulating paper. A plurality of CCDs arranged in the insulating oil
A camera, and an image processing device that performs image processing by inputting image data captured by the plurality of CCD cameras,
A monitoring device for a transformer, wherein a gap between the multilayer coil surface and the insulating paper is monitored based on a contact surface image of the multilayer coil surface and the insulating paper processed by the image processing device.