Gas chamber trace leakage detection method

Abstract

The invention discloses a gas chamber trace leakage detection device and method. The device comprises a multi-connection capillary tube, a gas chamber, a booster pump, a temperature detection structure, a pressure detection structure and a liquid level detection structure. The multi-connection capillary tube is provided with an air chamber tubular column and a pressurizing tubular column which are vertically arranged, and the lower end of the air chamber tubular column is communicated with the lower end of the pressurizing tubular column. And the multi-connection capillary tube is filled with liquid. And an air outlet of the air chamber is communicated with the upper end of the air chamber tubular column in a cuttable manner. And a gas outlet of the booster pump is communicated with the upper ends of the gas chamber tubular column and the booster tubular column in a cuttable manner. The temperature detection structure is used for detecting the gas temperature at the gas outlet. The pressure detection structure is used for detecting gas pressure at the gas outlet. The liquid level detection structure is used for detecting the height of liquid in the gas chamber tubular column. According to the invention, the pressure difference caused by trace gas leakage in the air chamber is linearly released by using the multi-connection capillary tube, so that quantitative monitoring of leakage is carried out, and accurate measurement of trace leakage is realized.

Description

Technical Field

[0001] This invention relates to the field of electrical engineering, and more particularly to a method for detecting minute leaks in a gas chamber. Background Technology

[0002] Sulfur hexafluoride (SF6) is widely used in power equipment (such as GIS switches, circuit breakers, and transformers) due to its excellent insulation and arc-quenching properties. However, SF6 gas leaks can lead to decreased equipment insulation performance, environmental pollution, and personnel poisoning risks. Therefore, leak detection technology has become a core requirement for safe operation and maintenance in the power industry. Traditional SF6 leak detection methods, such as the soap bubble method and the wrapping method, have low accuracy; infrared imaging methods are difficult to identify minute leaks; electrochemical methods suffer from sensor saturation and significant drift problems; and ultrasonic methods are susceptible to environmental noise interference. None of these methods are suitable for online monitoring of minute leaks and can only detect leaks in a single chamber, failing to meet the high-efficiency operation and maintenance needs of multi-chamber equipment. Summary of the Invention

[0003] This invention provides a method for detecting minute leaks in a gas chamber, which enables accurate measurement of minute leaks.

[0004] This invention provides a micro-leakage detection device for a gas chamber, comprising a multi-capillary tube, a gas chamber, a booster pump, a temperature detection structure, a pressure detection structure, and a liquid level detection structure. The multi-capillary tube has a gas chamber column and a booster column, both vertically arranged, with their lower ends connected. The multi-capillary tube is filled with liquid. The gas outlet of the gas chamber is disconnectably connected to the upper end of the gas chamber column. The gas outlet of the booster pump is disconnectably connected to the upper ends of both the gas chamber column and the booster column. The temperature detection structure detects the gas temperature at the gas outlet. The pressure detection structure detects the gas pressure at the gas outlet. The liquid level detection structure detects the liquid level within the gas chamber column.

[0005] In some embodiments, the gas chamber column includes a first gas chamber column, a second gas chamber column, and a third gas chamber column, the lower ends of which are connected to the lower ends of the first, second, and third gas chamber columns and the pressurization column. Each gas chamber has an outlet that is disconnectably connected to the upper ends of the first, second, and third gas chamber columns. The gas outlet is also disconnectably connected to the upper ends of the first, second, and third gas chamber columns and the pressurization column. A temperature detection structure is used to detect the gas temperature at the outlets of the first, second, and third gas chambers. A liquid level detection structure is used to detect the liquid level within the first, second, and third gas chamber columns.

[0006] In some embodiments, the gas chamber micro-leakage detection device further includes a booster valve body, a first valve body, a second valve body, and a third valve body. The booster valve body has a first air passage, a second air passage, and a third air passage, all of which are operable. One end of each of the first, second, and third air passages is connected; the other end of the first air passage is connected to a booster pump, and the other end of the second air passage is connected to a booster tubing. The first valve body has a first gas chamber air passage, a first tubing air passage, and a first booster air passage, all of which are operable. One end of each of these air passages is connected. The other end of the first gas chamber air passage is connected to the first gas chamber; the other end of the first tubing air passage is connected to the first gas chamber tubing; and the other end of the first booster air passage is connected to the other end of the third air passage. The second valve body has a second gas chamber air passage, a second tubing air passage, and a second booster air passage, all of which are operable. One end of each of these air passages is connected. The other end of the second air chamber air passage is connected to the second air chamber, the other end of the second tubular air passage is connected to the second air chamber tubular passage, and the other end of the second booster air passage is connected to the other end of the third air passage. The third valve body has a third air chamber air passage, a third tubular air passage, and a third booster air passage, all of which are operable and disconnectable. One end of each of these three air passages is connected. The other end of the third air chamber air passage is connected to the third air chamber, the other end of the third tubular air passage is connected to the third air chamber tubular passage, and the other end of the third booster air passage is connected to the other end of the third air passage.

[0007] In some embodiments, the temperature detection structure includes a first temperature sensor, a second temperature sensor, and a third temperature sensor. The first temperature sensor is disposed on the connecting pipe between the first gas chamber and the first gas chamber. The second temperature sensor is disposed on the connecting pipe between the second gas chamber and the second gas chamber. The third temperature sensor is disposed on the connecting pipe between the third gas chamber and the third gas chamber.

[0008] In some embodiments, the pressure detection structure includes a pressure sensor. The pressure sensor is disposed on the connecting pipe between the first air passage and the booster pump.

[0009] An embodiment of the present invention provides a method for detecting minor leaks in the gas chamber of the aforementioned gas chamber micro-leakage detection device, comprising the following steps: acquiring the gas pressure P, temperature T, and volume V within the gas chamber, and acquiring the liquid density ρ and gravitational acceleration g. Pressurizing the pressurization column until the pressure within the pressurization column reaches P4. Filling the gas chamber into the gas chamber column with the gas inside, and after the liquid height within the gas chamber column stabilizes, acquiring the liquid height h within the gas chamber column. When detecting gas leakage in the gas chamber, acquiring the current liquid height h′ within the gas chamber, and acquiring the current temperature T′ within the gas chamber. The gas leakage amount Δm of the gas chamber is obtained based on P, T, V, ρ, g, h, h′, and T′.

[0010] In some embodiments, obtaining the air pressure P, temperature T, and volume V in the air chamber includes: obtaining the air pressure P1, temperature T1, and volume V1 in the first air chamber, the air pressure P2, temperature T2, and volume V2 in the second air chamber, and the air pressure P3, temperature T3, and volume V3 in the third air chamber.

[0011] The gas in the gas chamber is filled into the gas chamber column. After the liquid height in the gas chamber column stabilizes, the liquid height h in the gas chamber column is obtained. This includes: filling the first gas chamber, the second gas chamber, and the third gas chamber column with the gas respectively. After the liquid height in the first gas chamber column, the second gas chamber column, and the third gas chamber column stabilizes, the liquid height h1 in the first gas chamber column, the liquid height h2 in the second gas chamber column, and the liquid height h3 in the third gas chamber column are obtained.

[0012] When detecting gas leakage in a gas chamber, the liquid height h′ in the current gas chamber and the temperature T′ in the current gas chamber are obtained, including: when detecting gas leakage in the first, second, and third gas chambers, the liquid height h′1, the liquid height h′2, and the liquid height h′3 in the first, second, and third gas chamber tubing are obtained, as well as the temperatures T′1, T′2, and T′3 in the first, second, and third gas chambers.

[0013] The gas leakage amount Δm of the gas chamber is obtained based on P, T, V, ρ, g, h, h′, and T′, including: obtaining the gas leakage amount Δm1 of the first gas chamber based on P1, T1, V1, ρ, g, h1, h′1, h2, h′2, h3, h′3, and T′1; obtaining the gas leakage amount Δm2 of the second gas chamber based on P2, T2, V2, ρ, g, h1, h′1, h2, h′2, h3, h′3, and T′2; and obtaining the gas leakage amount Δm3 of the third gas chamber based on P3, T3, V3, ρ, g, h1, h′1, h2, h′2, h3, h′3, and T′3.

[0014] In some embodiments, obtaining the gas leakage amount Δm1 of the first gas chamber based on P1, T1, V1, ρ, g, h1, h′1, and T′1 includes: obtaining the gas density ρ in the first gas chamber before gas leakage detection based on T1 and P1. a1 The liquid movement distance Δh′1 in the first gas chamber column is obtained based on h1 and h′1; the liquid movement distance Δh′2 in the second gas chamber column is obtained based on h2 and h′2; and the liquid movement distance Δh′3 in the third gas chamber column is obtained based on h3 and h′3. The gas pressure P′1 in the first gas chamber during gas leakage detection is obtained based on Δh′1, Δh′2, Δh′3, P1, ρ, and g. The gas density ρ′ in the first gas chamber during gas leakage detection is obtained based on T′1 and P′1.a1 According to ρ a1 ,ρ′ a1 Obtain the change in gas density Δρ1 in the first gas chamber. Calculate Δm1 based on Δρ1 and V1.

[0015] The gas leakage amount Δm2 of the second gas chamber is obtained based on P2, T2, V2, ρ, g, h2, h′2, and T′2, including: the gas density ρ in the second gas chamber before gas leakage detection is obtained based on T2 and P2. a2 The liquid movement distance Δh′1 in the first gas chamber column is obtained based on h1 and h′1; the liquid movement distance Δh′2 in the second gas chamber column is obtained based on h2 and h′2; and the liquid movement distance Δh′3 in the third gas chamber column is obtained based on h3 and h′3. The gas pressure P′2 in the second gas chamber during gas leakage detection is obtained based on Δh′1, Δh′2, Δh′3, P2, ρ, and G. The gas pressure ρ′ in the second gas chamber during gas leakage detection is obtained based on T′2 and P′2. a2 According to ρ a2 ,ρ′ a2 Obtain the change in gas density Δρ2 in the second chamber. Calculate Δm2 based on Δρ2 and V2.

[0016] The gas leakage amount Δm3 of the third gas chamber is obtained based on P3, T3, V3, ρ, g, h3, h′3, and T′3, including: the gas density ρ in the third gas chamber before gas leakage detection is obtained based on T3 and P3. a3 The liquid movement distance Δh′1 in the first gas chamber column is obtained based on h1 and h′1; the liquid movement distance Δh′2 in the second gas chamber column is obtained based on h2 and h′2; and the liquid movement distance Δh′3 in the third gas chamber column is obtained based on h3 and h′3. The gas pressure P′3 in the third gas chamber during gas leakage detection is obtained based on Δh′1, Δh′2, Δh′3, P3, ρ, and g. The gas pressure ρ′ in the third gas chamber during gas leakage detection is obtained based on T′3 and P′3. a3 According to ρ a3 ,ρ′ a3 Obtain the change in gas density Δρ3 in the third chamber. Calculate Δm3 based on Δρ3 and V3.

[0017] In some embodiments, the gas pressure P′1 in the first gas chamber during gas leakage detection is obtained based on Δh′1, Δh′2, Δh′3, P1, ρ, g, including: P′1=P1-ρg(2Δh′1+Δh′2+Δh′3).

[0018] The gas pressure P′2 in the second chamber during gas leakage detection is obtained based on Δh′1, Δh′2, Δh′3, ρ, and g. It includes: P′2 = P2 - ρg(Δh′1 + 2Δh′2 + Δh′3).

[0019] The gas pressure P′3 in the third chamber during gas leakage detection is obtained based on Δh′1, Δh′2, Δh′3, P3, ρ, and g, including: P′3 = P3 - ρg(Δh′1 + Δh′2 + 2Δh′3).

[0020] In some embodiments, P4 is the maximum value among P1, P2, and P3.

[0021] A micro-leakage detection device for a gas chamber according to an embodiment of the present invention includes a multi-capillary tube, a gas chamber, a booster pump, a temperature detection structure, a pressure detection structure, and a liquid level detection structure. The multi-capillary tube has a gas chamber column and a booster column, both vertically arranged, with their lower ends connected. The multi-capillary tube is filled with liquid. The gas outlet of the gas chamber is disconnectably connected to the upper end of the gas chamber column. The gas outlet of the booster pump is disconnectably connected to the upper ends of both the gas chamber column and the booster column. The temperature detection structure is used to detect the gas temperature at the gas outlet. The pressure detection structure is used to detect the gas pressure at the gas outlet. The liquid level detection structure is used to detect the liquid level in the gas chamber column. This invention utilizes a multi-capillary tube to linearly amplify the pressure difference caused by micro-leakage in the gas chamber, thereby enabling quantitative monitoring of the leak and achieving accurate measurement of micro-leakage, effectively overcoming the failure risk of conventional sensors under low leakage conditions. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the device in an embodiment of the present invention.

[0024] Figure 2 This is a schematic diagram of the booster valve body in an embodiment of the present invention;

[0025] Figure 3 This is a schematic diagram of the structure of the first valve body in an embodiment of the present invention;

[0026] Figure 4 This is a schematic diagram of the structure of the second valve body in an embodiment of the present invention;

[0027] Figure 5This is a schematic diagram of the structure of the third valve body in an embodiment of the present invention. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0029] See Figure 1-5 The present invention provides a micro-leakage detection device for a gas chamber, comprising a multi-capillary tube 1, a first gas chamber 2, a second gas chamber 3, a third gas chamber 4, a booster pump 5, a booster valve body 6, a first valve body 7, a second valve body 8, a third valve body 9, a temperature detection structure, a pressure detection structure, a liquid level detection structure, and a control structure.

[0030] The multi-capillary tube 1 has a first gas chamber column 101, a second gas chamber column 102, a third gas chamber column 103, and a pressurizing column 104, all vertically arranged. The lower ends of the first gas chamber column 101, the second gas chamber column 102, the third gas chamber column 103, and the pressurizing column 104 are connected. The first gas chamber column 101, the second gas chamber column 102, the third gas chamber column 103, and the pressurizing column 104 have the same length and are arranged on the same vertical plane. The multi-capillary tube 1 is filled with a liquid. The liquid includes mercury and an ionic liquid 106, which is located above the mercury in the first gas chamber column 101, the second gas chamber column 102, the third gas chamber column 103, and the pressurizing column 104. Ionic liquid 106 (NaFSI) has extremely low volatility and a wide liquid temperature range. It can isolate mercury from the gas (SF6 gas) in the gas chamber filled with multi-capillary tube 1, thus preventing mercury vapor from contaminating the gas in the gas chamber.

[0031] The outlet of the first air chamber 2 is disconnected from the upper end of the first air chamber tube 101. That is, the outlet of the first air chamber 2 is connected to the upper end of the first air chamber tube 101, and the connection can also be cut off.

[0032] The first gas chamber 2 contains SF6 gas.

[0033] The outlet of the second air chamber 3 is disconnected from the upper end of the second air chamber tube 102. That is, the outlet of the second air chamber 3 is connected to the upper end of the first air chamber tube 101, and the connection can be cut off.

[0034] The second chamber 3 contains SF6 gas.

[0035] The outlet of the third air chamber 4 is disconnected from the upper end of the third air chamber tube 103. That is, the outlet of the third air chamber 4 is connected to the upper end of the first air chamber tube 101, and the connection can be cut off.

[0036] The third chamber 4 contains SF6 gas.

[0037] The gas outlet of the booster pump 5 can be disconnected from the upper ends of the first gas chamber column 101, the second gas chamber column 102, the third gas chamber column 103, and the booster column 104. That is, the gas outlet of the booster pump 5 can be connected to the upper ends of the first gas chamber column 101, the second gas chamber column 102, the third gas chamber column 103, and the booster column 104, and the connection can also be disconnected.

[0038] The booster valve body 6 has a first air passage 601, a second air passage 602, and a third air passage 603, all of which are operable. One end of each of the three air passages is connected; the other end of the first air passage 601 is connected to the booster pump 5, and the other end of the second air passage 602 is connected to the booster tubing 104. The booster valve body 6 can be a three-way solenoid valve. Each of the first air passage 601, second air passage 602, and third air passage 603 is equipped with a valve to control its on / off state.

[0039] The first valve body 7 has a first air chamber passage 701, a first tubular air passage 702, and a first pressurizing air passage 703, all of which are operable. One end of each of these passages is connected. The other end of the first air chamber passage 701 is connected to the first air chamber 2, the other end of the first tubular air passage 702 is connected to the first air chamber tubular 101, and the other end of the first pressurizing air passage 703 is connected to the other end of the third air passage 603. The first valve body 7 can be a three-way solenoid valve. Each of the first air chamber passage 701, the first tubular air passage 702, and the first pressurizing air passage 703 is equipped with a valve to control its on / off state.

[0040] The second valve body 8 has a second air chamber passage 801, a second tubular air passage 802, and a second pressurizing air passage 803, all of which are operable. One end of each of these passages is connected. The other end of the second air chamber passage 801 is connected to the second air chamber 3, the other end of the second tubular air passage 802 is connected to the second air chamber tubular 102, and the other end of the second pressurizing air passage 803 is connected to the other end of the third air passage 603. The second valve body 8 can be a three-way solenoid valve. Valves controlling the on / off state are provided on the second air chamber passage 801, the second tubular air passage 802, and the second pressurizing air passage 803.

[0041] The third valve body 9 has a third air chamber passage 901, a third tubular air passage 902, and a third pressurizing air passage 903, all of which are operable. One end of each of these passages is connected. The other end of the third air chamber passage 901 is connected to the third air chamber 4, the other end of the third tubular air passage 902 is connected to the third air chamber tubular 103, and the other end of the third pressurizing air passage 903 is connected to the other end of the third air passage 603. The fourth valve body can be a three-way solenoid valve. Each of the third air chamber passage 901, the third tubular air passage 902, and the third pressurizing air passage 903 is equipped with a valve to control its on / off state.

[0042] The temperature detection structure is used to detect the gas temperature at the outlets of the first gas chamber 2, the second gas chamber 3, and the third gas chamber 4. The temperature detection structure includes a first temperature sensor 10, a second temperature sensor 11, and a third temperature sensor 12. The first temperature sensor 10 is installed on the connecting pipe between the first gas chamber air passage 701 and the first gas chamber 2. The second temperature sensor 11 is installed on the connecting pipe between the second gas chamber air passage 801 and the second gas chamber 3. The third temperature sensor 12 is installed on the connecting pipe between the third gas chamber air passage 901 and the third gas chamber 4.

[0043] The pressure detection structure is used to detect the gas pressure at the gas outlet. The pressure detection structure includes a pressure sensor 13. The pressure sensor 13 is installed on the connecting pipe between the first gas passage 601 and the booster pump 5.

[0044] The liquid level detection structure is used to detect the liquid level in the first gas chamber column 101, the second gas chamber column 102, and the third gas chamber column 103, specifically detecting the mercury column height 105 within these three columns. The liquid level detection structure includes a first infrared beam structure 15, a second infrared beam structure 16, a third infrared beam structure 17, and a fourth infrared beam structure 18. The first infrared beam structure 15 is located at the first gas chamber column 101 and is used to detect the liquid level within it, specifically detecting the mercury column height 105. The second infrared beam structure 16 is located at the second gas chamber column 102 and is used to detect the liquid level within it, specifically detecting the mercury column height 105. The third infrared beam structure 17 is located at the third gas chamber column 103 and is used to detect the liquid level within the third gas chamber column 103, specifically the height of the mercury column 105 within the third gas chamber column 103. The fourth infrared beam structure 18 is located at the pressurization column 104 and is used to detect the liquid level within the pressurization column 104, specifically the height of the mercury column 105 within the pressurization column 104. Under the above conditions, when gas enters the multi-capillary tube 1 from the gas chamber to be measured, the pressure difference will cause the mercury column 105 to rise or fall. During the rise or fall of the mercury column 105 in the multi-capillary tube 1, the range of the infrared beam structure being blocked changes, thereby determining the position of the mercury column 105.

[0045] The control structure includes a microcontroller 13 and an auxiliary circuit 14 connected to the microcontroller 13. The auxiliary circuit 14 is connected to the booster pump 5, the booster valve body 6, the first valve body 7, the second valve body 8, the third valve body 9, the first temperature sensor 10, the second temperature sensor 11 and the third temperature sensor 12, the pressure sensor 13, the first infrared beam structure 15, the second infrared beam structure 16, the third infrared beam structure 17 and the fourth infrared beam structure 18 to provide power.

[0046] An embodiment of the present invention also provides a method for detecting micro-leakage in a gas chamber using the above-described gas chamber micro-leakage detection device, comprising the following steps:

[0047] (1) Obtain the air pressure P1, temperature T1 and volume V1 in the first air chamber 2, the air pressure P2, temperature T2 and volume V2 in the second air chamber 3, the air pressure P3, temperature T3 and volume V3 in the third air chamber 4, and obtain the density ρ and gravitational acceleration g of the liquid.

[0048] In the above steps, obtaining the air pressure P1 in the first air chamber 2 includes: closing all air passages of the second valve body 8 and the third valve body 9, opening the first air chamber air passage 701 and the first booster air passage 703 of the first valve body 7, closing the first tubing air passage 702, opening the first air passage 601 and the third air passage 603 of the booster valve body 6, closing the second air passage 602, reading the air pressure P1 in the first air chamber 2 through the pressure sensor 13, and reading the temperature T1 in the first air chamber 2 at this time through the first temperature sensor 10.

[0049] Obtaining the air pressure P2 in the second air chamber 3 includes: closing all air passages of the first valve body 7 and the third valve body 9, opening the second air chamber air passage 801 and the second booster air passage 803 of the second valve body 8, closing the second tubing air passage 802, opening the first air passage 601 and the third air passage 603 of the booster valve body 6, closing the second air passage 602, reading the air pressure P2 in the second air chamber 3 through the pressure sensor 13, and reading the temperature T2 in the second air chamber 3 at this time through the second temperature sensor 11.

[0050] Obtaining the air pressure P3 in the third air chamber 4 includes: closing all air passages of the first valve body 7 and the second valve body 8, opening the third air chamber air passage 901 and the third booster air passage 903 of the third valve body 9, closing the third tubing air passage 902, opening the first air passage 601 and the third air passage 603 of the booster valve body 6, closing the second air passage 602, reading the air pressure P3 in the third air chamber 4 through the pressure sensor 13, and reading the temperature T3 in the third air chamber 4 at this time through the third temperature sensor 12.

[0051] (2) Pressurize the pressurization column 104 until the pressure inside the pressurization column 104 reaches P4. Fill the first gas chamber 2, the second gas chamber 3 and the third gas chamber 4 into the first gas chamber column 101, the second gas chamber column 102 and the third gas chamber column 103 respectively. After the liquid height in the first gas chamber column 101, the second gas chamber column 102 and the third gas chamber column 103 stabilizes, obtain the liquid height h1 in the first gas chamber column 101, the liquid height h2 in the second gas chamber column 102 and the liquid height h3 in the third gas chamber column 103.

[0052] In the above steps, P4 is the maximum value among P1, P2, and P3, in order to control the pressure difference and prevent backflow of the mercury column 105 beyond its range. Pressurizing the booster column 104 until the pressure reaches P4 includes: opening the first air passage 601 and the second air passage 602 of the booster valve body 6, closing the third air passage 603, turning on the booster pump 5, and pressurizing the multi-capillary tube 1 until P4 is reached and stabilized. Then, the first air passage 601 of the booster valve body 6 is closed, and the pressure is allowed to stabilize for 5-10 minutes to allow the pressure in the pipeline to self-balance. When checking the pressure in the multi-capillary tube 1, the first air passage 601 and the second air passage 602 of the booster valve body 6 are opened, and the pressure sensor 13 reads whether the pressure in the multi-capillary tube 1 has reached P4.

[0053] The gas in the first gas chamber 2, the second gas chamber 3, and the third gas chamber 4 is respectively filled into the first gas chamber column 101, the second gas chamber column 102, and the third gas chamber column 103, including: opening the first gas chamber gas passage 701 and the first column gas passage 702 of the first valve body 7, closing the first booster gas passage 703; opening the second gas chamber gas passage 801 and the second column gas passage 802 of the second valve body 8, closing the second booster gas passage 803; opening the third gas chamber gas passage 901 and the third column gas passage 902 of the third valve body 9, closing the third booster gas passage 903, and filling the multi-capillary tube 1 with gas. After the liquid levels in the first gas chamber column 101, the second gas chamber column 102, and the third gas chamber column 103 stabilize, the liquid levels h1, h2, and h3 in the first gas chamber column 101, the second gas chamber column 102, and the third gas chamber column 103 are obtained. This includes: taking readings when the inflation stabilizes until the mercury column 105 stops moving, recording the upward or downward stroke of the mercury column 105, and determining the horizontal height as h1, h2, and h3 in the first gas chamber column 101, the second gas chamber column 102, and the third gas chamber column 103. Additionally, the mercury column 105 in the pressurization column 104 is determined to be at a horizontal height of h4.

[0054] (3) When detecting the gas leakage of the first gas chamber 2, the second gas chamber 3 and the third gas chamber 4, the liquid height h′1 in the first gas chamber tube 101, the liquid height h′2 in the second gas chamber tube 102 and the liquid height h′3 in the third gas chamber tube 103 are obtained, as well as the temperature T′1 in the first gas chamber 2, the temperature T′2 in the second gas chamber 3 and the temperature T′3 in the third gas chamber 4 are obtained.

[0055] In the above steps, before detecting the gas leakage of the first gas chamber 2, the second gas chamber 3, and the third gas chamber 4, the first gas chamber gas passage 701 and the first tubular gas passage 702 of the first valve body 7 are kept open, and the first booster gas passage 703 is closed. The second gas chamber gas passage 801 and the second tubular gas passage 802 of the second valve body 8 are opened, and the second booster gas passage 803 is closed. The third gas chamber gas passage 901 and the third tubular gas passage 902 of the third valve body 9 are opened, and the third booster gas passage 903 is closed.

[0056] The system acquires the current liquid height h′1 in the first gas chamber column 101, the liquid height h′2 in the second gas chamber column 102, and the liquid height h′3 in the third gas chamber column 103, as well as the current temperatures T′1 in the first gas chamber 2, T′2 in the second gas chamber 3, and T′3 in the third gas chamber 4. This includes: moving the mercury column 105 in the first gas chamber column 101 to a horizontal height of h′1 and reading the temperature T′1 in the first gas chamber 2; moving the mercury column 105 in the second gas chamber column 102 to a horizontal height of h′2 and reading the temperature T′2 in the second gas chamber 3; moving the mercury column 105 in the third gas chamber column 103 to a horizontal height of h′3 and reading the temperature T′3 in the third gas chamber 4; and moving the mercury column 105 in the pressurization column 104 to a horizontal height of h′4. Furthermore, the pressure in the pressurization column 104 remains constant, ΔP4=0.

[0057] (4) Obtain the gas leakage amount Δm1 of the first gas chamber 2 based on P1, T1, V1, ρ, g, h1, h′1, h2, h′2, h3, h′3, T′1. Obtain the gas leakage amount Δm2 of the second gas chamber 3 based on P2, T2, V2, ρ, g, h1, h′1, h2, h′2, h3, h′3, T′2. Obtain the gas leakage amount Δm3 of the third gas chamber 4 based on P3, T3, V3, ρ, g, h1, h′1, h2, h′2, h3, h′3, T′3.

[0058] The above steps involve obtaining the gas leakage amount Δm1 of the first gas chamber 2 based on P1, T1, V1, ρ, g, h1, h′1, h2, h′2, h3, h′3, and T′1, including the following process:

[0059] A1. Based on T1 and P1, the gas density ρ in the first gas chamber 2 before gas leakage detection is obtained. a1 .

[0060] The following formula is used in the above process:

[0061]

[0062] A = 73.882 × 10 -5 -5.132105×10 -7 ρ a1.

[0063] B = 2.50695 × 10 -3 -2.12283×10 -6 ρ a1 .

[0064] R = 56.9502 × 10 -5 .

[0065] A2. Obtain the liquid movement distance Δh′1 in the first gas chamber column 101 according to h1 and h′1, obtain the liquid movement distance Δh′2 in the second gas chamber column 102 according to h2 and h′2, and obtain the liquid movement distance Δh′3 in the third gas chamber column 103 according to h3 and h′3.

[0066] In the above process, the difference between h1 and h′1 is Δh′1, the difference between h2 and h′2 is Δh′2, and the difference between h3 and h′3 is Δh′3.

[0067] A3. Obtain the gas pressure P′1 in the first gas chamber 2 when performing gas leakage detection based on Δh′1, Δh′2, Δh′3, P1, ρ, g.

[0068] The following formula is used in the above process:

[0069] P′1=P1-ρg(2Δh′1+Δh′2+Δh′3).

[0070] The above formula is obtained as follows: At initial equilibrium, the horizontal plane containing the upper ends of the first gas chamber column 101, the second gas chamber column 102, the third gas chamber column 103, and the pressurization column 104 is taken as the reference plane. This is the horizontal plane at which liquid seeps out from the first gas chamber column 101, the second gas chamber column 102, the third gas chamber column 103, and the pressurization column 104. The pressure on the reference plane is equal everywhere, therefore P1 + ρgh1 = P4 + ρgh4. At final equilibrium, the pressure on the reference plane is again equal everywhere, therefore P′1 + ρg(h1 + Δh′1) = P4 + ρg(h4 + Δh′4). ΔP1 = P1 - P′1. Therefore, ΔP1 = ρg(Δh′4 - Δh′1). Furthermore, since the cross-sectional area A of each tube is the same and the mercury column 105 is incompressible, the conservation of total volume requires that the algebraic sum of the changes in liquid level be zero. Therefore, AΔh′1 + AΔh′2 + AΔh′3 + AΔh′4 = 0. In summary, ΔP1 = -ρg(2Δh′1 + Δh′2 + Δh′3). Finally, we obtain P′1 = P1 - ρg(2Δh′1 + Δh′2 + Δh′3).

[0071] A4. Based on T′1 and P′1, the gas density ρ′ in the first gas chamber 2 is obtained during the gas leakage detection. a1 .

[0072] The following formula is used in the above process:

[0073]

[0074] A = 73.882 × 10 -5 -5.132105×10 -7 ρ′ a1 .

[0075] B = 2.50695 × 10 -3 -2.12283×10 -6 ρ′ a1 .

[0076] R = 56.9502 × 10 -5 .

[0077] A5. According to ρ a1 ,ρ′ a1 Obtain the change in gas density Δρ1 in the first gas chamber 2.

[0078] In the above process, Δρ1=ρ a1 -ρ′ a1 .

[0079] A6. Obtain Δm1 based on Δρ1 and V1.

[0080] In the above process, Δm1=Δρ1×V1.

[0081] The gas leakage Δm2 of the second gas chamber 3 is obtained based on P2, T2, V2, ρ, g, h1, h′1, h2, h′2, h3, h′3, and T′2, including the following process:

[0082] B1. Based on T2 and P2, the gas density ρ in the second chamber 3 before gas leakage detection is obtained. a2 .

[0083] The following formula is used in the above process:

[0084]

[0085] A = 73.882 × 10 -5 -5.132105×10 -7 ρ a2 .

[0086] B = 2.50695 × 10 -3 -2.12283×10 -6 ρ a2 .

[0087] R = 56.9502 × 10 -5.

[0088] B2. Obtain the liquid movement distance Δh′1 in the first gas chamber column 101 according to h1 and h′1, obtain the liquid movement distance Δh′2 in the second gas chamber column 102 according to h2 and h′2, and obtain the liquid movement distance Δh′3 in the third gas chamber column 103 according to h3 and h′3.

[0089] In the above process, the difference between h1 and h′1 is Δh′1, the difference between h2 and h′2 is Δh′2, and the difference between h3 and h′3 is Δh′3.

[0090] B3. Obtain the gas pressure P′2 in the second gas chamber 3 when performing gas leakage detection based on Δh′1, Δh′2, Δh′3, P2, ρ, g.

[0091] The following formula is used in the above process:

[0092] P′2=P2-ρg(Δh′1+2Δh′2+Δh′3).

[0093] The above formulas are obtained as follows: At initial equilibrium, the pressure on the reference surface is equal everywhere, so P2 + ρgh2 = P4 + ρgh4. At final equilibrium, the pressure on the reference surface is again equal everywhere, so P′2 + ρg(h2 + Δh′2) = P4 + ρg(h4 + Δh′4). ΔP2 = P2 - P′2. Therefore, ΔP2 = ρg(Δh′4 - Δh′2). Furthermore, since the cross-sectional area A of each tube is the same and the mercury column 105 is incompressible, the conservation of total volume requires the algebraic sum of the changes in liquid level to be zero, so AΔh′1 + AΔh′2 + AΔh′3 + AΔh′4 = 0. Therefore, ΔP2 = -ρg(Δh′1 + 2Δh′2 + Δh′3). Finally, P′2 = P2 - ρg(Δh′1 + 2Δh′2 + Δh′3).

[0094] B4. Based on T′2 and P′2, the gas pressure ρ′ in the second chamber 3 is obtained during the gas leakage detection. a2 .

[0095] The following formula is used in the above process:

[0096]

[0097] A = 73.882 × 10 -5 -5.132105×10 -7 ρ′ a2 .

[0098] B = 2.50695 × 10 -3 -2.12283×10 -6 ρ′ a2 .

[0099] R = 56.9502 × 10 -5 .

[0100] B5. According to ρ a2 ,ρ′ a2 Obtain the change in gas density Δρ2 in the second gas chamber 3.

[0101] In the above process, Δρ2=ρ a2 -ρ′ a2 .

[0102] B6. Obtain Δm2 based on Δρ2 and V2.

[0103] In the above process, Δm2=Δρ2×V2.

[0104] The gas leakage Δm3 of the third gas chamber 4 is obtained based on P3, T3, V3, ρ, g, h1, h′1, h2, h′2, h3, h′3, and T′3, including:

[0105] C1. Based on T3 and P3, the gas density ρ in the third chamber 4 before gas leakage detection is obtained. a3 .

[0106] The following formula is used in the above process:

[0107]

[0108] A = 73.882 × 10 -5 -5.132105×10 -7 ρ a3 .

[0109] B = 2.50695 × 10 -3 -2.12283×10 -6 ρ a3 .

[0110] R = 56.9502 × 10 -5 .

[0111] C2. Obtain the liquid movement distance Δh′1 in the first gas chamber column 101 according to h1 and h′1, obtain the liquid movement distance Δh′2 in the second gas chamber column 102 according to h2 and h′2, and obtain the liquid movement distance Δh′3 in the third gas chamber column 103 according to h3 and h′3.

[0112] In the above process, the difference between h1 and h′1 is Δh′1, the difference between h2 and h′2 is Δh′2, and the difference between h3 and h′3 is Δh′3.

[0113] C3. Obtain the gas pressure P′3 in the third chamber 4 when performing gas leakage detection based on Δh′1, Δh′2, Δh′3, P3, ρ, and g.

[0114] The following formula is used in the above process:

[0115] P′3=P3-ρg(Δh′1+Δh′2+2Δh′3).

[0116] The above formulas are obtained as follows: At initial equilibrium, the pressure on the reference surface is equal everywhere, so P3 + ρgh3 = P4 + ρgh4. At final equilibrium, the pressure on the reference surface is again equal everywhere, so P′3 + ρg(h3 + Δh′3) = P4 + ρg(h4 + Δh′4). ΔP3 = P3 - P′3. Therefore, ΔP3 = ρg(Δh′4 - Δh′3). Furthermore, since the cross-sectional area A of each tube is the same and the mercury column 105 is incompressible, the conservation of total volume requires the algebraic sum of the changes in liquid level to be zero, so AΔh′1 + AΔh′2 + AΔh′3 + AΔh′4 = 0. Therefore, ΔP3 = -ρg(Δh′1 + Δh′2 + 2Δh′3). Finally, P′3 = P3 - ρg(Δh′1 + Δh′2 + 2Δh′3).

[0117] C4. The gas pressure Δρ′ in the third chamber 4 is obtained based on T′3 and P′3 when detecting gas leakage. a3 .

[0118] The following formula is used in the above process:

[0119]

[0120] A = 73.882 × 10 -5 -5.132105×10 -7 ρ′ a3 .

[0121] B = 2.50695 × 10 -3 -2.12283×10 -6 ρ′ a3 .

[0122] R = 56.9502 × 10 -5 .

[0123] C5. According to Δρ a3 ,Δρ′ a3 Obtain the change in gas density Δρ3 in the third gas chamber 4.

[0124] In the above process, Δρ3=ρ a3 -ρ′ a3 .

[0125] C6. Obtain Δm3 based on Δρ3 and V3.

[0126] In the above process, Δm3=Δρ3×V3.

[0127] Some existing technologies use gas flow rate meters for quantitative analysis, but their accuracy is low for detecting trace amounts of gas leaks and they cannot continuously monitor the gas chamber under test for extended periods. Other existing technologies rely on non-dispersive infrared spectroscopy to calculate SF6 concentration by measuring the attenuation of the characteristic absorption peak at 10.55 μm. However, these technologies do not detect the amount of SF6 leaked, but rather the concentration of SF6 diffused in the air, which has been diluted and cannot be used to deduce the amount of SF6 leaked.

[0128] To address the challenge of capturing pressure changes caused by minute leaks, this invention utilizes a micron-level flow channel structure with multiple capillary tubes (1) to linearly amplify the pressure difference within the gas chamber caused by minute gas leaks. This enables quantitative monitoring of leaks and precise measurement of minute leaks, effectively overcoming the failure risk of conventional sensors under low-leakage conditions. In practical engineering environments, multiple gas chambers are often used simultaneously. For power equipment operating with multiple gas chambers in parallel, this invention employs a multi-channel collaborative detection architecture with multiple capillary tubes (1), breaking through the efficiency bottleneck of traditional single-point detection modes. It can simultaneously monitor leaks in multiple independent gas chambers and perform quantitative leak calculations, significantly reducing engineering costs and maintenance difficulty, offering both significant economic and environmental benefits. This invention combines an infrared beam structure with a dynamic compensation algorithm to achieve precise quantitative leakage, making it particularly suitable for minute leak scenarios. This invention automatically triggers an alarm when the leakage reaches a threshold, further enhancing its economic and environmental benefits. This invention is easy to maintain and highly stable. This invention significantly improves the engineering applicability and reliability of SF6 gas chamber leak detection.

[0129] In the accompanying drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components. In the description of this invention, it should be understood that if terms such as "upper," "lower," "left," and "right" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, they are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the accompanying drawings are only for illustrative purposes and should not be construed as limiting this patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0130] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A device for detecting minute leaks in a gas chamber, characterized in that, include: A multi-capillary tube has a vertically arranged air chamber column and a pressurization column, the lower ends of which are connected; the multi-capillary tube is filled with liquid. The air chamber and its outlet are disconnected from the upper end of the air chamber tubing. The booster pump has its gas outlet disconnected from both the gas chamber tubing and the upper end of the booster tubing. A temperature detection structure is used to detect the gas temperature at the outlet. A pressure detection structure is used to detect the gas pressure at the gas outlet; A liquid level detection structure is used to detect the liquid level inside the gas chamber column.

2. The gas chamber micro-leakage detection device as described in claim 1, characterized in that, The air chamber tubing includes a first air chamber tubing, a second air chamber tubing, and a third air chamber tubing, and the lower ends of the first air chamber tubing, the second air chamber tubing, the third air chamber tubing, and the pressurization tubing are connected. The air chamber includes a first air chamber, a second air chamber, and a third air chamber. The air outlets of the first air chamber, the second air chamber, and the third air chamber are respectively connected to the upper ends of the first air chamber tubing, the second air chamber tubing, and the third air chamber tubing in a cut-off manner. The gas outlet can be disconnected from the upper ends of the first gas chamber column, the second gas chamber column, the third gas chamber column, and the pressurization column; The temperature detection structure is used to detect the gas temperature at the outlets of the first gas chamber, the second gas chamber, and the third gas chamber; The liquid level detection structure is used to detect the liquid level in the first gas chamber column, the second gas chamber column, and the third gas chamber column.

3. The gas chamber micro-leakage detection device as described in claim 2, characterized in that, Also includes: The booster valve body has a first air passage, a second air passage, and a third air passage, all of which can be switched on or off; one end of the first air passage, the second air passage, and the third air passage are connected together, the other end of the first air passage is connected to the booster pump, and the other end of the second air passage is connected to the booster tubing. The first valve body has a first air chamber passage, a first tubular passage, and a first pressurizing passage, all of which are openable and closedable. One end of the first air chamber passage, the first tubular passage, and the first pressurizing passage are connected together. The other end of the first air chamber passage is connected to the first air chamber, the other end of the first tubular passage is connected to the first air chamber tubular passage, and the other end of the first pressurizing passage is connected to the other end of the third passage. The second valve body has a second air chamber passage, a second tubular passage, and a second pressurizing passage, all of which are openable and closedable. One end of the second air chamber passage, the second tubular passage, and the second pressurizing passage are connected together. The other end of the second air chamber passage is connected to the second air chamber, the other end of the second tubular passage is connected to the second air chamber tubular passage, and the other end of the second pressurizing passage is connected to the other end of the third passage. The third valve body has a third air chamber passage, a third tubular passage, and a third pressurizing passage, all of which are operable. One end of the third air chamber passage, the third tubular passage, and the third pressurizing passage are connected together. The other end of the third air chamber passage is connected to the third air chamber, the other end of the third tubular passage is connected to the third air chamber tubular passage, and the other end of the third pressurizing passage is connected to the other end of the third air passage.

4. The gas chamber micro-leakage detection device as described in claim 3, characterized in that, The temperature detection structure includes: The first temperature sensor is installed on the connecting pipe between the first air chamber and the first air chamber. The second temperature sensor is installed on the connecting pipe between the second air chamber and the second air chamber. The third temperature sensor is installed on the connecting pipe between the third air chamber and the third air chamber.

5. The gas chamber micro-leakage detection device as described in claim 3, characterized in that, The pressure detection structure includes: A pressure sensor is installed on the connecting pipe between the first air path and the booster pump.

6. A method for detecting minor leaks in a gas chamber using the gas chamber minor leak detection device according to any one of claims 1-5, characterized in that, Includes the following steps: The pressure P, temperature T, and volume V of the air chamber are obtained, as well as the density ρ and gravitational acceleration g of the liquid. Pressurize the booster string until the pressure inside the booster string reaches P4; The gas in the gas chamber is filled into the gas chamber column. After the liquid level in the gas chamber column stabilizes, the liquid level h in the gas chamber column is obtained. When detecting gas leakage in the gas chamber, the current liquid height h′ in the gas chamber and the current temperature T′ in the gas chamber are obtained. The gas leakage rate Δm of the gas chamber is obtained based on P, T, V, ρ, g, h, h′, and T′.

7. The method for detecting minute leaks in a gas chamber as described in claim 6, characterized in that, Obtain the air pressure P, temperature T, and volume V within the air chamber, including: Obtain the air pressure P1, temperature T1 and volume V1 in the first air chamber, the air pressure P2, temperature T2 and volume V2 in the second air chamber, and the air pressure P3, temperature T3 and volume V3 in the third air chamber. Gas is introduced into the gas chamber of the gas chamber into the gas chamber column. After the liquid level in the gas chamber column stabilizes, the liquid level h in the gas chamber column is obtained, including: The gases in the first gas chamber, the second gas chamber, and the third gas chamber are respectively filled into the first gas chamber tube, the second gas chamber tube, and the third gas chamber tube. After the liquid heights in the first gas chamber tube, the second gas chamber tube, and the third gas chamber tube are stabilized, the liquid heights h1, h2, and h3 in the first gas chamber tube, respectively are obtained. When detecting gas leakage in the gas chamber, the current liquid height h' in the gas chamber and the current temperature T' in the gas chamber are obtained, including: When detecting gas leakage in the first gas chamber, the second gas chamber, and the third gas chamber, the liquid height h'1, the liquid height h'2, and the liquid height h'3 in the first gas chamber tube are obtained, as well as the current temperature T'1, the temperature T'2, and the temperature T'3 in the first gas chamber, the second gas chamber, and the third gas chamber are obtained. The gas leakage rate Δm of the gas chamber is obtained based on P, T, V, h, g, h, h′, and T′, including: The gas leakage amount Δm1 of the first gas chamber is obtained based on P1, T1, V1, ρ, g, h1, h′1, h2, h′2, h3, h′3, and T′1. The gas leakage Δm2 of the second gas chamber is obtained based on P2, T2, V2, ρ, g, h1, h′1, h2, h′2, h3, h′3, and T′2. According to P3, T3, V 3. ρ, g, h1, h′1, h2, h′2, h3, h′3, T′3 are used to obtain the gas leakage amount Δm3 of the third gas chamber.

8. The method for detecting minute leaks in a gas chamber as described in claim 7, characterized in that, The gas leakage Δm1 of the first gas chamber is obtained based on P1, T1, V1, ρ, g, h1, h′1, and T′1, including: Based on T1 and P1, the gas density ρ in the first gas chamber before gas leakage detection is obtained. a1 ; The liquid movement distance Δh′1 in the first air chamber tube is obtained according to h1 and h′1; the liquid movement distance Δh′2 in the second air chamber tube is obtained according to h2 and h′2; and the liquid movement distance Δh′3 in the third air chamber tube is obtained according to h3 and h′3. The gas pressure P′1 in the first gas chamber during gas leakage detection is obtained based on Δh′1, Δh′2, Δh′3, P1, ρ, and g. The gas density ρ′ in the first gas chamber is obtained based on T′1 and P′1 during gas leakage detection. a1 ; According to ρ a1 ,ρ′ a1 Obtain the gas density change Δρ1 in the first air chamber; Δm1 is obtained from Δρ1 and V1; The gas leakage Δm2 of the second gas chamber is obtained based on P2, T2, V2, ρ, g, h2, h′2, and T′2, including: Based on T2 and P2, the gas density ρ in the second chamber before gas leakage detection is obtained. a2 ; The liquid movement distance Δh1 in the first air chamber tube is obtained according to h1 and h2; the liquid movement distance Δh′2 in the second air chamber tube is obtained according to h2 and h2; and the liquid movement distance Δh′3 in the third air chamber tube is obtained according to h3 and h′3. The gas pressure P′2 in the second chamber during gas leakage detection is obtained based on Δh′1, Δh′2, Δh′3, P2, ρ, and g. The gas pressure ρ′ in the second chamber during gas leakage detection is obtained based on T′2 and P′2. a2 ; According to ρ a2 ,ρ′ a2 Obtain the change in gas density Δρ2 in the second chamber; Δm2 is obtained from Δρ2 and V2; The gas leakage rate Δm3 of the third gas chamber is obtained based on P3, T3, V3, ρ, g, h3, h′3, and T′3, including: The gas density ρ in the third chamber, obtained based on T3 and P3, is used for gas leakage detection. a3 ; The liquid movement distance Δh′1 in the first air chamber tube is obtained according to h1 and h′1, the liquid movement distance Δh′2 in the second air chamber tube is obtained according to h2 and h′2, and the liquid movement distance Δh′3 in the third air chamber tube is obtained according to h3 and h′3. The gas pressure P′3 in the third chamber during gas leakage detection is obtained based on Δh′1, Δh′2, Δh′3, P3, ρ, and g. The gas pressure ρ′ in the third chamber during gas leakage detection is obtained based on T′3 and P′3. a3 ; According to ρ a3 ,ρ′ a3 Obtain the gas density change Δρ3 in the third chamber; Δm3 is obtained from Δρ3 and V3.

9. The method for detecting minute leaks in a gas chamber as described in claim 8, characterized in that, The gas pressure P′1 in the first gas chamber during gas leakage detection is obtained based on Δh′1, Δh′2, Δh′3, P1, ρ, and g, including: P′1=P1-ρg(2Δh′1+Δh′2+Δh′3); The gas pressure P′2 in the second chamber during gas leakage detection is obtained based on Δh′1, Δh′2, Δh′3, P2, ρ, and g, including: P′2=P2-ρg(Δh′1+2Δh′2+Δh′3); The gas pressure P'3 in the third chamber during gas leakage detection is obtained based on Δh′1, Δh′2, Δh′3, P3, ρ, and g, including: P'3=P3-ρg(Δh'1+Δh'2+2Δh'3).

10. The method for detecting minute leaks in a gas chamber as described in claim 7, characterized in that, P4 is the maximum value among P1, P2, and P3.

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