CN-121978015-A - Gas detection system with high-sensitivity H-type photoacoustic cell

CN121978015ACN 121978015 ACN121978015 ACN 121978015ACN-121978015-A

Abstract

The invention discloses a gas detection system with a high-sensitivity H-shaped photoacoustic cell, which comprises a photoacoustic cell assembly, a first cylinder body assembly and a second cylinder body assembly, wherein the photoacoustic cell assembly comprises a shell (1), a first protruding part is arranged on the A side of the shell (1), a laser (2) is arranged in the first protruding part, a first lens (3) is arranged in the emergent direction of the laser (2), a second protruding part is also arranged on the A side of the shell (1), a second lens (4), a third lens (5), a reference cell (6) and a pyramid (7) are arranged in the second protruding part, a Porro prism (8) is arranged on the B side inside the shell (1), the A side and the B side are opposite, meanwhile, the Porro prism (8) can reflect laser emitted in the laser (2) into the second protruding part, and a photoacoustic cell (9) is also arranged in the middle of the shell (1).

Inventors

WANG HUAIZHI
LIU XIAO
GUO JIANTAO
LI CHUANGUO
ZHAO DAN
LIU WANG
LI BO
ZHANG ZHENGSHUN

Assignees

大连世有电力科技有限公司

Dates

Publication Date: 20260505
Application Date: 20251226

Claims (3)

1. A gas detection system with high-sensitivity H-shaped photoacoustic cells is characterized by comprising a photoacoustic cell assembly, a first cylinder assembly and a second cylinder assembly, The photoacoustic cell assembly comprises a shell (1), wherein a first protruding part is arranged on the A side of the shell (1), a laser (2) is arranged in the first protruding part, a first lens (3) is arranged in the emergent direction of the laser (2), a second protruding part is also arranged on the A side of the shell (1), a second lens (4), a third lens (5), a reference cell (6) and a pyramid (7) are arranged in the second protruding part, a Porro prism (8) is arranged on the B side inside the shell (1), the A side and the B side are opposite two side surfaces, meanwhile, the Porro prism (8) can reflect laser emitted by the laser (2) into the second protruding part, a photoacoustic cell (9) is also arranged in the middle of the shell (1), The first cylinder body assembly comprises a first stepping motor (10), the working end of the first stepping motor (10) is connected with a first screw rod (11), a nut seat is connected to the first screw rod (11) in a threaded manner, the nut seat is connected with a piston rod in a first cylinder body (12), the top of the first cylinder body (12) is connected with a first exhaust pipeline (13), an electromagnetic valve (14) and a liquid level switch shell (15) are sequentially arranged on the first exhaust pipeline (13), a liquid level sensor is arranged in the liquid level switch shell (15), an exhaust gas discharge pipeline (16) with an air valve is also arranged on the liquid level switch shell (15), The second cylinder body component comprises a second stepping motor (17), the working end of the second stepping motor (17) is connected with a second screw rod (18), a nut seat is connected on the second screw rod (18) in a threaded manner, the nut seat is connected with a piston rod in a second cylinder body (19), the top of the second cylinder body (19) is connected with a second exhaust pipeline (20), The first exhaust pipeline (13) and the second exhaust pipeline (20) are respectively connected with two passages of a two-position three-way valve (21), the other passage of the two-position three-way valve (12) is connected with an air inlet pipeline of the photoacoustic cell assembly, an air inlet valve (22) is also arranged on the air inlet pipeline, The first cylinder body (12) is connected with an oil way (23), the oil way is respectively communicated with an oil inlet pipeline (25) and an oil return pipeline (26) through a three-way joint (24), and oil valves are arranged on the oil inlet pipeline (25) and the oil return pipeline (26).
2. The gas detection system with high-sensitivity H-type photoacoustic cell of claim 1, wherein the first cylinder assembly further comprises a first photoelectric switch (27), a second photoelectric switch (28) and a third photoelectric switch (29), a first trigger plate (30) capable of triggering the three photoelectric switches respectively is arranged on the nut seat, when the piston in the first cylinder (12) is in two limit positions respectively, the first trigger plate (30) triggers the first photoelectric switch (27) and the third photoelectric switch (29) respectively, and when a sufficient amount of oil available for detection is absorbed in the first cylinder (12), the first trigger plate (30) triggers the second photoelectric switch (28).
3. The gas detection system with high-sensitivity H-type photoacoustic cell of claim 1, wherein the second cylinder assembly further comprises a fourth photoelectric switch (31) and a fifth photoelectric switch (32), a second trigger plate (33) capable of triggering the two photoelectric switches respectively is arranged on the nut seat, and when the piston in the second cylinder (16) is in two limit positions respectively, the second trigger plate (33) triggers the fourth photoelectric switch (31) and the fifth photoelectric switch (32) respectively.

Description

Gas detection system with high-sensitivity H-type photoacoustic cell Technical Field The invention relates to the field of detection of power equipment, in particular to a gas detection system with a high-sensitivity H-shaped photoacoustic cell. Background The insulation state of locomotive high-voltage electrical equipment (such as traction transformers, oil-immersed reactors and the like) is the core for guaranteeing the railway transportation safety. At present, fault diagnosis is performed by analyzing fault characteristic gases (such as H 2、CO、CH4、C2H2、C2H4、C2H6 and the like) dissolved in insulating oil, and the fault diagnosis is an effective method in industry recognition. In the conventional fault characteristic gas detection process, a detection technology based on a photoacoustic spectrum principle, namely a photoacoustic cell detection technology, is mostly adopted. The method is quantified by detecting the acoustic signal generated by absorbing the modulated light by the gas, and has the potential of high selectivity, no consumption and good stability. However, in this detection method based on the photoacoustic spectrum principle, the longer the path of the laser beam is, the higher the detection accuracy is, so that in order to pursue high-accuracy detection, the volume of the photoacoustic cell needs to be made relatively large (long), and a large space needs to be occupied; meanwhile, the traditional photoacoustic cell fault gas detection device can directly input primary separation gas of oil into the photoacoustic cell for detection, but in practice, the oil can also undergo multiple separation operations such as secondary separation, tertiary separation and the like, in each separated gas, the content of the fault characteristic gas may be different, and the traditional operation mode (directly detecting the separated gas once) has larger deviation, so that accurate measurement cannot be realized. There is therefore a need for a method or apparatus that solves the above problems. Disclosure of Invention The invention aims to solve the defects in the prior art, and provides the gas detection system with the high sensitivity H-type photoacoustic cell, which has the characteristics of simple structure, ingenious design, reasonable layout, capability of uniformly detecting the mixed gas after multiple separation, capability of ensuring the accuracy of detection results, small volume and the like. The technical proposal of the invention is that the gas detection system with the high-sensitivity H-shaped photoacoustic cell is characterized in that the detection system comprises three parts of a photoacoustic cell assembly, a first cylinder body assembly and a second cylinder body assembly, The photoacoustic cell assembly comprises a shell 1, wherein a first protruding part is arranged on the side A of the shell 1, a laser 2 is arranged in the first protruding part, a first lens 3 is arranged in the emergent direction of the laser 2, a second protruding part is also arranged on the side A of the shell 1, a second lens 4, a third lens 5, a reference cell 6 and a pyramid 7 are arranged in the second protruding part, a Porro prism 8 is arranged on the side B inside the shell 1, the side A and the side B are opposite, meanwhile, the Porro prism 8 can reflect laser emitted by the laser 2 into the second protruding part, a photoacoustic cell 9 is also arranged in the middle of the shell 1, The first cylinder body assembly comprises a first stepping motor 10, the working end of the first stepping motor 10 is connected with a first screw rod 11, a nut seat is connected on the first screw rod 11 in a threaded manner, the nut seat is connected with a piston rod in a first cylinder body 12, the top of the first cylinder body 12 is connected with a first exhaust pipeline 13, an electromagnetic valve 14 and a liquid level switch shell 15 are sequentially arranged on the first exhaust pipeline 13, a liquid level sensor is arranged in the liquid level switch shell 15, an exhaust gas discharge pipeline 16 is also arranged on the liquid level switch shell 15, The second cylinder body assembly comprises a second stepping motor 17, the working end of the second stepping motor 17 is connected with a second screw rod 18, a nut seat is connected on the second screw rod 18 in a threaded manner, the nut seat is connected with a piston rod in a second cylinder body 19, the top of the second cylinder body 19 is connected with a second exhaust pipeline 20, The first exhaust pipeline 13 and the second exhaust pipeline 20 are respectively connected with two passages of a two-position three-way valve 21, the other passage of the two-position three-way valve 12 is connected with an air inlet pipeline of the photoacoustic cell assembly, an air inlet valve 22 is also arranged on the air inlet pipeline, The first cylinder body 12 is connected with an oil path 23, the oil path is respectively communicated with an oil inlet pipeli