CN110726521A

CN110726521A - Leakage detection device and transformer

Info

Publication number: CN110726521A
Application number: CN201911054251.7A
Authority: CN
Inventors: 张文松; 赵洪波
Original assignee: Xi'an And Its Polytron Technologies Inc
Current assignee: Xi'an And Its Polytron Technologies Inc
Priority date: 2019-10-31
Filing date: 2019-10-31
Publication date: 2020-01-24

Abstract

The disclosure relates to a leakage detection device and a transformer, the leakage detection device comprises a shell, an optical element, a light emitter, a light receiver and a circuit board, wherein the optical element is arranged in an installation cavity and divides the installation cavity into a first cavity and a second cavity, and the optical element has a preset refractive index; the light emitter and the light receiver are both arranged in the first cavity, and the light emitter is used for emitting incident light vertical to the incident surface; when the refractive index of the medium of the second cavity is smaller than the preset refractive index, the incident light can generate total reflection on the reflecting surface and can be emitted to the light receiver perpendicular to the incident surface; when the refractive index of the medium of the second cavity is larger than the preset refractive index, the incident light can generate half reflection on the reflecting surface, and the reflected light can be emitted to the light receiver perpendicular to the incident surface; the circuit board is arranged in the first cavity and connected with the light emitter and the light receiver, and the circuit board can output matched light intensity signals according to the light intensity acquired by the light receiver.

Description

Leakage detection device and transformer

Technical Field

The disclosure relates to the technical field of transformers, in particular to a leakage detection device and a transformer.

Background

Power transformers are one of the main devices of power plants and substations, which are used to transform an alternating voltage (current) of a certain value into another voltage (current) of the same frequency or different values. The oil conservator is a kind of oil storage device for the transformer, when the volume of the transformer oil expands or shrinks along with the change of the oil temperature, the oil conservator has the function of storing and supplementing oil, and can ensure the oil tank is full of oil. Meanwhile, the oil conservator is arranged, so that the contact surface of the transformer and the air is reduced, and the moisture, dust and oxidized oil dirt absorbed from the air are deposited in the depositor at the bottom of the oil conservator, thereby greatly slowing down the degradation speed of the transformer oil.

Usually, the air bag is arranged in the oil conservator and used for isolating transformer oil from atmosphere, avoiding direct contact and balancing the pressure in the transformer box body and the pressure in the outside atmosphere. When the pressure in the box body is high, the air bag exhausts outwards, and when the atmospheric pressure is higher than the pressure in the box body, the air bag inhales, so that the breathing effect is achieved.

However, the airbag is prone to rupture and oil leakage due to reasons such as improper operation and overlong use time, so that the problem of the oil level meter of the transformer conservator is caused, the real oil level cannot be reflected, the condition of wrong oil level judgment is caused, and if the problem cannot be found in time, even serious accidents such as trip and the like due to too low misjudgment value of the oil level can occur.

It is to be noted that the information disclosed in the above background section is only for enhancement of understanding of the background of the present disclosure, and thus may include information that does not constitute prior art known to those of ordinary skill in the art.

Disclosure of Invention

The invention aims to provide a leakage detection device and a transformer, which can realize accurate judgment of medium types under the condition of known medium types.

According to an aspect of the present disclosure, there is provided a leak detection apparatus including:

the shell is cylindrical and is provided with an installation cavity;

the optical element is arranged in the installation cavity and divides the installation cavity into a first cavity and a second cavity, an opening is formed in the shell of the second cavity, the optical element has a preset refractive index, and the optical element comprises an incident surface facing the first cavity and a reflecting surface facing the second cavity;

the light emitter and the light receiver are arranged in the first cavity, and the light emitter is used for emitting incident light vertical to the incident surface; when the refractive index of the medium of the second cavity is smaller than the preset refractive index, the incident light can generate total reflection on the reflecting surface and can be emitted to the light receiver perpendicular to the incident surface; when the refractive index of the medium of the second cavity is larger than the preset refractive index, the incident light can generate half reflection on the reflecting surface, and the reflected light can be emitted to the light receiver perpendicular to the incident surface;

the circuit board is arranged in the first cavity, the circuit board is connected with the light emitter and the light receiver, and the circuit board can output matched light intensity signals according to the light intensity acquired by the light receiver.

In an exemplary embodiment of the present disclosure, the optical element is an isosceles triangular prism.

In an exemplary embodiment of the present disclosure, the optical element is an isosceles trapezoidal prism.

In an exemplary embodiment of the present disclosure, the optical element is a ball lens.

In an exemplary embodiment of the present disclosure, the predetermined refractive index is 1.3334-1.3900.

In an exemplary embodiment of the present disclosure, the medium is at least one of water, air, or transformer oil.

In an exemplary embodiment of the present disclosure, the light emitter is a laser emitter.

In an exemplary embodiment of the present disclosure, the laser transmitter includes an LED light source or an LD light source.

In an exemplary embodiment of the present disclosure, the leak detection apparatus further includes:

and one end of the signal wire is connected with the circuit board, the other end of the signal wire is used for being connected with a terminal, and the signal wire is used for transmitting the light intensity signal.

According to another aspect of the present disclosure, a transformer is provided, which includes the leakage detecting device provided in any one of the above embodiments.

According to the leakage detection device provided by the disclosure, when the refractive index of the medium in the second cavity is smaller than the preset refractive index, light rays are emitted to the light sparse medium from the optically dense medium, and the emergent angle of the light rays in the optical element is larger than the critical angle of the light rays emitted to the medium by controlling the angle between the incident light of the light emitter and the reflecting surface, so that the light rays are totally reflected in the optical element; when the refractive index of the medium of the second cavity is larger than the preset refractive index, the light rays are emitted to the optically-dense medium from the optically-sparse medium, and the light rays cannot be totally reflected when the light rays are emitted to the optically-dense medium from the optically-sparse medium, so that the light rays are semi-reflected in the optical element, and part of the light rays are projected into the medium. After the light reflected by the optical element is received by the light receiver, the circuit board can output a matched light intensity signal according to the intensity of the reflected light acquired by the light receiver, and further can judge whether the refractive index of the medium of the second cavity of the prism is larger than or smaller than the preset refractive index of the optical element according to the light intensity signal. In case the type of media is known, a determination of the type of media can be achieved.

In addition, the medium type is judged through the optical element, the light emitter, the light receiver and the circuit board, and the difficulty of the installation and operation process of the leakage detection device can be reduced.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and together with the description, serve to explain the principles of the disclosure. It is to be understood that the drawings in the following description are merely exemplary of the disclosure, and that other drawings may be derived from those drawings by one of ordinary skill in the art without the exercise of inventive faculty.

FIG. 1 is a schematic view of a leak detection apparatus provided in an embodiment of the present disclosure;

fig. 2 is a schematic view illustrating light propagation in a light source device according to an embodiment of the present disclosure;

fig. 3 is a schematic view illustrating light propagation in a light source element according to another embodiment of the present disclosure.

Description of reference numerals:

11. optical element, 12, light emitter, 13, light receiver, 14, circuit board, 15, casing, 16, signal line.

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. Example embodiments may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and thus their detailed description will be omitted.

Although relative terms, such as "upper" and "lower," may be used in this specification to describe one element of an icon relative to another, these terms are used in this specification for convenience only, e.g., in accordance with the orientation of the examples described in the figures. It will be appreciated that if the device of the icon were turned upside down, the element described as "upper" would become the element "lower". When a structure is "on" another structure, it may mean that the structure is integrally formed with the other structure, or that the structure is "directly" disposed on the other structure, or that the structure is "indirectly" disposed on the other structure via another structure.

The terms "a," "an," "the," "said," and "at least one" are used to indicate the presence of one or more elements/components/parts/etc.; the terms "comprising" and "having" are intended to be inclusive and mean that there may be additional elements/components/etc. other than the listed elements/components/etc.; the terms "first," "second," and the like are used merely as labels, and are not limiting on the number of their objects.

The applicant has found that it is common to transmit and receive light through optical fibers, and to provide a cavity at the probe position, which causes the optical path to deflect due to the change of refractive index when immersed in oil, thereby causing the received light intensity to change. However, when water exists in the oil bag, the light intensity is weakened to influence oil leakage judgment, and whether the air bag leaks oil or not cannot be accurately judged; in addition, when the transmission medium is an optical fiber, the optical fiber is easily broken, which results in complicated installation and operation processes.

The disclosed embodiment provides a leakage detection device and a transformer, as shown in fig. 1, the leakage detection device includes a housing 15, an optical element 11, a light emitter 12, a light receiver 13, and a circuit board 14. The housing 15 is cylindrical and has a mounting cavity; the optical element 11 is arranged in the installation cavity and divides the installation cavity into a first cavity and a second cavity, an opening is arranged on a shell 15 of the second cavity so that a medium can be in contact with the optical element 11, the optical element 11 has a preset refractive index, and the optical element 11 comprises an incident surface facing the first cavity and a reflecting surface facing the second cavity; the light emitter 12 and the light receiver 13 are both arranged in the first cavity, and the light emitter 12 is used for emitting incident light perpendicular to an incident surface; when the refractive index of the medium in the second cavity is smaller than the preset refractive index, the incident light can generate total reflection on the reflecting surface and can be emitted to the light receiver 13 perpendicular to the incident surface; when the refractive index of the medium in the second cavity is greater than the preset refractive index, the incident light can generate half reflection on the reflecting surface, and the reflected light can be emitted to the light receiver 13 perpendicular to the incident surface; the circuit board 14 is arranged in the first cavity, the circuit board 14 is connected with the light emitter 12 and the light receiver 13, and the circuit board 14 can output a matched light intensity signal according to the light intensity acquired by the light receiver 13.

Wherein, the medium is at least one of water, air or transformer oil. For example, the leakage detection device is used for detecting whether an air bag in a transformer conservator leaks oil or not, when the air bag is intact, the medium is air or water, and when the air bag breaks leakage, the medium is oil. In general, the refractive index of air is 1.0003, the refractive index of water is 1.3333, the refractive index of oil used for cooling and insulation in the transformer is more than 1.3900, the refractive index of the optical element 11 is smaller than that of oil and larger than that of air and water, that is, the refractive index of the optical element 11 may be 1.3334 to 1.3900, for example 1.3500, 1.3600, 1.3700, etc., which are not listed here. Meanwhile, the preset incident angle of the light emitter 12 on the incident surface of the optical element 11 is larger than the angle which can make the light totally reflect in the optical element 11 when the medium is water or air, so that when the second cavity is air or water, the angle of the light entering the optical element 11 on the emergent surface of the optical element 11 is larger than the critical angle, and the light totally reflects in the optical element 11. When the second cavity is oil, the light beam is emitted from the light source element to the oil and is emitted from the optically thinner medium to the optically denser medium, the light beam is semi-reflected in the optical element 11, part of the light beam is emitted to the oil, and the light beam reflected to the light receiver 13 is greatly reduced. After the light reflected by the optical element 11 is received by the light receiver 13, because when the medium is water, air or oil, the intensity difference of the light received by the light receiver 13 is large, the circuit board 14 can output a matched light intensity signal according to the intensity of the reflected light acquired by the light receiver 13, and then can judge whether the medium of the second cavity of the prism is oil or not according to the light intensity signal, thereby realizing the detection of whether the oil leaks from the air bag in the conservator or not.

As shown in fig. 1, the leak detector further includes a signal line 16, one end of the signal line 16 is connected to the circuit board 14, the other end is used for connecting to a terminal, and the signal line 16 is used for transmitting a light intensity signal.

Specifically, the signal line 16 is adopted to connect the circuit board 14 with the terminal, and the signal line 16 has higher stability, so that the installation of the leakage detection device is simpler, and the signal transmission between the leakage detection device and the terminal is more reliable, thereby realizing the real-time monitoring on whether oil leaks in the conservator air bag or not and improving the reliability of the leakage detection device.

In addition, a spare signal line 16 for connecting the circuit board 14 and the terminal can be arranged, and when the signal line 16 in use has transmission failure, the spare signal line 16 can be started to ensure the transmission of signals, so that the reliability of the leakage detection device is further improved. Meanwhile, when the standby signal line 16 is started, if the signal can not be normally transmitted as it is, the fault can be judged to be on the circuit board, so that the fault generation position can be judged, the maintenance efficiency of the leakage detection device is improved, and the maintenance cost of the leakage detection device is reduced.

As shown in fig. 1, the leak detection device further includes a housing 15, the housing 15 has a mounting cavity, and the optical element 11, the optical transmitter 12, the optical receiver 13 and the circuit board 14 are disposed in the mounting cavity. Through casing 15's setting, form seal chamber, seal chamber forms the installation that holds of each part, play simultaneously to each parts damp-proofing effect, especially avoid producing on the optical element 11 that the optics that results in penetrates into optical element 11 and the angle of the light of condensed water or other liquid of adhesion takes place the problem appearance that changes, also avoided the circuit board to wet simultaneously and lead to the problem appearance that became invalid, guaranteed the performance and the life of each part in the device that leaks hunting, improved the reliability of device that leaks hunting.

Further, the optical element 11 divides the mounting cavity into a first cavity and a second cavity; the light emitter 12, the light receiver 13 and the circuit board 14 are sealed in a first cavity, and a second cavity is used for accommodating a medium.

The housing 15 may be cylindrical or prismatic, and the housing 15 is made of stainless steel, so as to prevent the housing 15 from rusting due to corrosion in a humid environment and ensure the reliability of the housing 15. Further, the housing 15 may also be aluminum, iron, a metal alloy material, or a plastic material, which is not limited by the present disclosure.

As shown in fig. 1, the optical element 11 is a prism. As shown in fig. 2, the optical element 11 is, for example, an isosceles triangular prism; alternatively, as shown in fig. 3, the optical element 11 is an isosceles trapezoidal prism; still alternatively, the optical element 11 may also be a lens, such as a ball lens. The optical element 11 may be made of plastic or glass, and those skilled in the art can select a prism or a lens with other shapes or materials, and all technical solutions with the same technical effects as the present application belong to the protection scope of the present application.

Specifically, the light emitter 12 is a laser emitter 12, and the laser emitter 12 is adopted, so that the angle of the emitted light entering the incident surface of the optical element 11 can be ensured, and the accuracy of the leakage detection device is improved.

The laser transmitter 12 includes an LED (light emitting diode) light source or an LD (semiconductor laser) light source, among others. When the laser emitter 12 uses an LED light source, it has the advantages of long service life, low cost, low power consumption, small size, high reliability, etc. When the laser transmitter 12 uses an LD light source, it has advantages of a small divergence angle of the light beam, a strong light, and the like.

The present disclosure also provides a transformer, which includes a conservator, an air bag disposed in the conservator, and the above leakage detecting device disposed in the air bag. Specifically, the leakage detection device is located at the bottom of the air bag, when the air bag is intact, oil in the conservator cannot enter the air bag, a medium of a second cavity of the optical element 11 is air or water, because the refractive index of the optical element 11 is larger than that of the air and the water, light rays emitted into the optical element 11 by the light emitter 12 are totally reflected, the intensity of reflected light rays received by the light receiver 13 is high, and the circuit board 14 outputs matched light ray intensity signals according to the light rays with high intensity obtained by the light receiver 13, so that the medium is judged to be water or air, and the integrity of the air bag is further determined. When the gasbag broke, oil in the conservator got into the gasbag, because the leak hunting device is located the bottom of gasbag, the oil that leaks into in the gasbag can directly reach the second cavity of optical element 11, because the refracting index of optical element 11 is less than the refracting index of oil, light can't take place the total reflection phenomenon, consequently light takes place half reflection in optical element 11, part light throws into in the oil, the reflected light intensity that light receiver 13 received is relatively weak, circuit board 14 is according to the light output matching's of weak intensity signal of light that light receiver 13 obtained, thereby judge the medium to be oil, and then confirm that the gasbag breaks, realize the real-time detection to gasbag in the conservator, guarantee the transformer normal work.

Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This application is intended to cover any variations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

Claims

1. A leak detection device, comprising:

the shell is cylindrical and is provided with an installation cavity;

2. The leak detection device of claim 1, wherein the optical element is an isosceles triangular prism.

3. The leak detection device of claim 1, wherein the optical element is an isosceles trapezoidal prism.

4. The leak detection device of claim 1, wherein the optical element is a ball lens.

5. The leak detection device as claimed in claim 1, wherein the predetermined refractive index is 1.3334-1.3900.

6. The leak detection apparatus of claim 1, wherein the medium is at least one of water, air, or transformer oil.

7. The leak detection device of claim 1, wherein the light emitter is a laser emitter.

8. The leak detection apparatus of claim 7, wherein the laser emitter comprises an LED light source or an LD light source.

9. The leak detection device of claim 1, further comprising:

10. A transformer, characterized by comprising a leakage detection device according to any one of claims 1-9.