Sensor and device for detecting content of dissolved hydrogen and acetylene in oil-immersed power equipment and preparation method
Through the all-fiber sensor technology, the combination of the optical fiber resonant ring formed by knots and the palladium silver alloy layer and molecular sieve material layer is used to realize real-time synchronous detection of dissolved hydrogen and acetylene in the oil, solving the problem of time lag in the detection results in the prior art and the inability to achieve in-situ detection, and improving the accuracy of fault warning and diagnosis.
Patent Information
- Application Number
- CN202510219675.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-26
- Publication Date
- 2025-05-30
AI Technical Summary
The existing DGA technology is difficult to achieve real-time rapid detection of dissolved hydrogen and acetylene in oil, and it is impossible to achieve in-situ detection of key positions inside the equipment, resulting in poor fault warning and diagnosis effects.
Using an all-fiber sensor, the sensor single-mode fiber formed by a single-mode fiber is achieved by using the first and second fiber resonant rings formed by knotting, combined with a palladium-silver alloy layer and a molecular sieve material layer to achieve synchronous detection of dissolved hydrogen and acetylene.
It realizes synchronous detection of dissolved trace hydrogen and acetylene content in transformer oil, and can quickly obtain gas characteristics in real time and enhances the accuracy of fault warning and diagnosis.
Smart Images
Figure CN120064122A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of power equipment status perception, and specifically relates to a sensor, a device and a preparation method for detecting the contents of dissolved hydrogen and acetylene in oil-immersed power equipment. Background Art
[0002] The UHV converter transformer is the energy conversion center of the new energy Internet. The insulating oil-paper structure of the UHV converter transformer and its bushing bears the combined action of high-strength and extremely uneven electrical, magnetic, thermal, and mechanical multi-physical fields. The valve-side insulation is subjected to the action of AC-DC composite voltage for a long time, resulting in frequent failures of the UHV converter transformer. The gases generated during the fault process are characteristic parameters reflecting the fault type, severity, and development trend of the transformer. The power industry standard: DL / T 722-2014 "Guidelines for the Analysis and Judgment of Dissolved Gases in Transformer Oil" clearly states that the analysis of dissolved gases in oil (DGA) is of great significance for realizing the intelligent diagnosis of power equipment faults and early warning of latent faults. Hydrogen and acetylene are the most typical and key fault characteristic gases among them: Hydrogen is the main accompanying gas during partial discharge and local overheating in the early stage of power equipment faults and is a key parameter for realizing early fault warning; Acetylene is a typical characteristic gas reflecting high-energy arc discharge and is considered a marker parameter for judging the occurrence of equipment faults and evaluating the severity of faults.
[0003] The existing DGA technology shows insurmountable technical limitations, which are reflected in: Oil-gas separation and multi-component gas separation are required, resulting in a serious time lag in the detection results. And a large number of studies and actual operation experiences show that the real-time and rapid acquisition of the absolute value of the fault gas content and the information of the gas production dynamic process is to realize fault warning and fault diagnosis; Implantable in-situ detection at key positions inside the equipment cannot be realized, resulting in a weak mapping relationship between the obtained gas characteristics and the fault point characteristics; The electromagnetic compatibility performance of electrical detection methods is poor, and the operation is easily affected by electromagnetic interference. Therefore, it is urgent to study the all-fiber online sensing technology for hydrogen and acetylene in oil. Summary of the Invention
[0004] To solve the problems existing in the prior art, the purpose of the present invention is to provide a sensor, a device and a preparation method for detecting the contents of dissolved hydrogen and acetylene in oil-immersed power equipment, and the present invention can realize the synchronous detection of the contents of trace dissolved hydrogen and acetylene in transformer oil.
[0005] To achieve the above purpose, the technical solution adopted by the present invention is as follows: A sensor for detecting the contents of dissolved hydrogen and acetylene in oil-immersed power equipment includes a first single-mode optical fiber, a sensing single-mode optical fiber, and a second single-mode optical fiber, and the first single-mode optical fiber, the sensing single-mode optical fiber, and the second single-mode optical fiber are connected in sequence; Among them, the sensing single-mode optical fiber is a structure formed by melting and tapering a single-mode optical fiber. The waist region of the sensing single-mode optical fiber is formed with a first optical fiber resonance ring and a second optical fiber resonance ring by knotting. The ring diameters of the first optical fiber resonance ring and the second optical fiber resonance ring are different, and both ends of the first optical fiber resonance ring and both ends of the second optical fiber resonance ring are fixed in position. A palladium-silver alloy layer is provided on the surface of the first optical fiber resonance ring; A palladium-silver alloy layer is provided on the surface of the second optical fiber resonance ring, and a molecular sieve material layer is provided on the surface of the palladium-silver alloy layer. The gas selection pore diameter of the molecular sieve material of the molecular sieve material layer is between the molecular sizes of hydrogen and acetylene.
[0006] Preferably, the diameter of the waist region is 10 μm to 15 μm.
[0007] Preferably, the diameter of the first optical fiber resonance ring is 0.2 mm to 1 mm, and the diameter of the second optical fiber resonance ring is 0.2 mm to 1 mm.
[0008] Preferably, the diameter difference between the first optical fiber resonance ring and the second optical fiber resonance ring is controlled within 0.5 mm to 0.1 mm.
[0009] Preferably, the thickness of the palladium-silver alloy layer is 100 nm to 300 nm.
[0010] Preferably, the thickness of the molecular sieve material layer is 50 nm to 100 nm.
[0011] Preferably, the molecular sieve material is Cu(FMA)(4,4-bpe) 0.5 , and the pore window diameter of the molecular sieve material is 3.3 Å.
[0012] Preferably, the fixing method for both ends of the first optical fiber resonance ring and both ends of the second optical fiber resonance ring is as follows: Both ends of the first optical fiber resonance ring and both ends of the second optical fiber resonance ring are fixed to a support sheet.
[0013] The present invention also provides a preparation method for the above sensor for detecting the content of dissolved hydrogen and acetylene in oil-immersed power equipment, including the following process: The sensing single-mode optical fiber is subjected to melting and tapering to form a tapered portion with a simple diameter and a waist region located between the two tapered portions at both ends on the sensing single-mode optical fiber; The first optical fiber resonance ring and the second optical fiber resonance ring are formed in the waist region by knotting, and then both ends of the first optical fiber resonance ring and both ends of the second optical fiber resonance ring are fixed in position; then a palladium-silver alloy layer is formed on the surfaces of the first optical fiber resonance ring and the second optical fiber resonance ring by magnetron sputtering, and then a molecular sieve material layer is formed on the surface of the palladium-silver alloy layer on the surface of the second optical fiber resonance ring by the method of molecular self-assembly; Fuse the large end of the tapered part at one end of the sensing single-mode optical fiber to one end of the first single-mode optical fiber, and fuse the large end of the tapered part at the other end of the sensing single-mode optical fiber to one end of the second single-mode optical fiber.
[0014] The present invention also provides a device for detecting the contents of dissolved hydrogen and acetylene in oil-immersed power equipment, which includes a broadband light source, a spectrometer, and the sensor for detecting the contents of dissolved hydrogen and acetylene in oil-immersed power equipment as described above in the present invention. Among them, the first single-mode optical fiber is connected to the broadband light source, and the second single-mode optical fiber is connected to the spectrometer.
[0015] The present invention has the following beneficial effects: In the sensor for detecting the contents of dissolved hydrogen and acetylene in oil-immersed power equipment of the present invention, a first optical fiber resonance ring and a second optical fiber resonance ring are formed in the waist region of the sensing single-mode optical fiber. Palladium-silver alloy layers are provided on the surfaces of both the first optical fiber resonance ring and the second optical fiber resonance ring. A molecular sieve material layer is further provided on the surface of the second optical fiber resonance ring on the palladium-silver alloy layer. Under the action of hydrogen and acetylene, the palladium-silver alloy will generate expansion stress, which will cause the ring diameters of the optical fiber resonance rings (i.e., the first optical fiber resonance ring and the second optical fiber resonance ring) to change, thereby outputting a resonance spectrum drift. Since only the palladium-silver alloy layer is provided on the surface of the first optical fiber resonance ring, the first optical fiber resonance ring is sensitive to both hydrogen and acetylene gases. However, since the second optical fiber resonance ring is further coated with a molecular sieve material layer on the outside (the molecular sieve material of this molecular sieve material layer only allows hydrogen to pass through, while acetylene gas cannot pass through), the resonance spectrum output by the second optical fiber resonance ring is only modulated by the hydrogen content. Therefore, by analyzing the output changes of the resonance spectra output by the two optical fiber resonance rings (i.e., the first optical fiber resonance ring and the second optical fiber resonance ring), the output spectrum change of the first optical fiber resonance ring is modulated by the contents of hydrogen and acetylene, while the change of the output spectrum of the second optical fiber resonance spectrum is only modulated by the hydrogen content. Furthermore, the decoupling of the hydrogen and acetylene contents can be realized, and the synchronous analysis of the gas components can be completed. Description of the Drawings
[0016] Figure 1 is a schematic diagram of the device for detecting the contents of dissolved hydrogen and acetylene in oil-immersed power equipment of the present invention.
[0017] Figure 2(a) is a detailed view of the first optical fiber resonance ring and the second optical fiber resonance ring in the embodiment of the present invention; Figure 2(b) is a schematic diagram of the sensing principle of the first optical fiber resonance ring in the embodiment of the present invention; Figure 2(c) is a schematic diagram of the sensing principle of the second optical fiber resonance ring in the embodiment of the present invention; Figure 3 is a schematic diagram of the gas molecule selection of the molecular sieve material layer in the embodiment of the present invention; Figure 4 is a schematic diagram of the output spectrum of the micro-nano optical fiber double-ring resonator in the embodiment of the present invention.
[0018] In the figure, 1 is a broadband light source, 2 is a first single-mode optical fiber, 3 is a sensing single-mode optical fiber, 3-1 is a tapered portion, 3-2 is a waist region, 4 is a first optical fiber resonator ring, 5 is a second optical fiber resonator ring, 6 is a second single-mode optical fiber, 7 is a spectrometer, 8 is a magnesium fluoride crystal sheet, 9 is a silicone gel, 10 is a palladium-silver alloy layer, and 11 is a molecular sieve material layer. Detailed implementation mode
[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings required for the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other accompanying drawings can be obtained based on these drawings without creative efforts.
[0020] See Figure 1 , Fig. 2(a), Fig. 2(b) and Fig. 2(c). The sensor for detecting the content of dissolved hydrogen and acetylene in oil-immersed power equipment in this embodiment includes a first single-mode optical fiber 2, a sensing single-mode optical fiber 3 and a second single-mode optical fiber 6. The first single-mode optical fiber 2, the sensing single-mode optical fiber 3 and the second single-mode optical fiber 6 are connected in sequence. Among them, the sensing single-mode optical fiber 3 is a structure formed by melting and tapering a single-mode optical fiber. The sensing single-mode optical fiber 3 of this structure has a waist region 3-2 in the middle and tapered portions 3-1 at both ends of the waist region 3-2. The waist region 3-2 of the sensing single-mode optical fiber 3 is formed with a first optical fiber resonator ring 4 and a second optical fiber resonator ring 5 by tying knots. The ring diameters of the first optical fiber resonator ring 4 and the second optical fiber resonator ring 5 are different, and the positions of both ends of the first optical fiber resonator ring 4 and both ends of the second optical fiber resonator ring 5 are fixed. A palladium-silver alloy layer 10 is provided on the surface of the first optical fiber resonator ring 4; a palladium-silver alloy layer 10 is provided on the surface of the second optical fiber resonator ring 5, and a molecular sieve material layer 11 is provided on the surface of the palladium-silver alloy layer 10. The gas selection pore diameter of the molecular sieve material of the molecular sieve material layer 11 is between the molecular sizes of hydrogen and acetylene. Since both ends of the first optical fiber resonator ring 4 and the second optical fiber resonator ring 5 are formed by tying knots and the positions of both ends are fixed, when the palladium-silver alloy layer 10 expands under the action of gas, the ring diameters of both ends of the first optical fiber resonator ring 4 and the second optical fiber resonator ring 5 can change, so as to realize the resonance spectrum drift of the first optical fiber resonator ring 4 and the second optical fiber resonator ring 5. The sensor provided in this embodiment can analyze the output spectra of the first optical fiber resonator ring 4 and the second optical fiber resonator ring 5 of the optical fiber and perform spectral information analysis to realize the analysis of the content of hydrogen and acetylene.
[0021] Among them, the ends of the first single-mode optical fiber 2 and the second single-mode optical fiber 6 are respectively connected to the tapered parts 3-1 at both ends of the sensing single-mode optical fiber 3 by means of fusion splicing. The surface of the first optical fiber resonator ring 4 is coated with a palladium-silver alloy layer 10 with a thickness of 100 nm to 300 nm. The surface of the second optical fiber resonator ring 5 is sequentially coated with a palladium-silver alloy layer 10 and a molecular sieve material layer 11. Among them, the thickness of the palladium-silver alloy layer 10 is 100 nm to 300 nm, and the thickness of the molecular sieve material layer 11 is 50 nm to 100 nm. See Figure 3 , the gas selection pore diameter of the molecular sieve material layer 11 is between the molecular sizes of hydrogen and acetylene, that is, hydrogen can pass through the molecular sieve material, and acetylene gas cannot pass through the molecular sieve material. The sensing single-mode optical fiber 3 is subjected to high-temperature melting and tapering, and the obtained waist region 3-2 has a length of 10 cm, and the diameter of the waist region 3-2 is 10 μm to 15 μm. Then, two knot-type resonator rings are sequentially formed in the waist region by means of knotting, namely the first optical fiber resonator ring 4 and the second optical fiber resonator ring. By controlling the ring diameters of the first optical fiber resonator ring 4 and the second optical fiber resonator ring 5, the output resonance spectra of the two resonator rings are separated. In the present invention, the diameters of the first optical fiber resonator ring 4 and the second optical fiber resonator ring are between 0.2 mm and 1 mm, and the difference in the ring diameters of the first optical fiber resonator ring 4 and the second optical fiber resonator ring 5 is controlled within the range of 0.5 mm to 0.1 mm.
[0022] In the above solution of the present invention, the fixing methods for the positions of both ends of the first optical fiber resonator ring 4 and both ends of the second optical fiber resonator ring 5 are as follows: both ends of the first optical fiber resonator ring 4 and both ends of the second optical fiber resonator ring 5 are fixed on a support sheet.
[0023] Embodiment The device for detecting the contents of dissolved hydrogen and acetylene in oil-immersed power equipment in this embodiment includes a broadband light source 1, a spectrometer 7, and the sensor for detecting the contents of dissolved hydrogen and acetylene in oil-immersed power equipment in the above embodiment. Among them, the first single-mode optical fiber 2 is connected to the broadband light source 1, and the second single-mode optical fiber 6 is connected to the spectrometer 7. The broadband light source 1 is incident on one end of the first single-mode optical fiber 2, and the other end of the single-mode optical fiber 2 is connected to the sensing single-mode optical fiber 3 by means of fusion splicing.
[0024] The surface of the first optical fiber resonator ring 4 is coated with a palladium-silver alloy layer 10, and the palladium-silver alloy layer 10 is prepared on the optical fiber resonator ring by means of magnetron sputtering, with a thickness of 150 nm; the surface of the second optical fiber resonator ring 5 is sequentially coated with a palladium-silver alloy layer 10 and a molecular sieve material layer 11. Among them, the palladium-silver alloy layer 10 is prepared on the optical fiber resonator ring by means of magnetron sputtering, with a thickness of 150 nm; the thickness of the molecular sieve material layer 11 is 50 nm to 100 nm, and it is prepared on the optical fiber resonator ring by means of molecular self-assembly. The schematic diagram of the sensing principle of the micro-nano optical fiber double-ring resonator cooperating with the gas molecular sieve is shown in Figures 2(a)-2(c).
[0025] The gas selection pore diameter of the molecular sieve material layer 11 is between the molecular sizes of hydrogen and acetylene, that is, hydrogen can pass through the molecular sieve material, while acetylene gas cannot penetrate the molecular sieve material; in this embodiment, Cu(FMA)(4,4-bpe) 0.5 is used as the molecular sieve material, and its pore window diameter is 3.3 Å. Therefore, it can be used to complete the selection of hydrogen and acetylene gas molecules. The schematic diagram of molecular sieve gas molecule selection is as Figure 3 shown.
[0026] The first optical fiber resonator ring 4 and the second optical fiber resonator ring 5 are controlled by the size of the ring diameter, so that the resonant spectra output by the two resonator rings are separated. During the process of knotting the micro-nano optical fiber, it is carried out on an optical micro-operation platform. In this embodiment, the diameter of the first optical fiber resonator ring 4 is 0.35 mm, and the diameter of the second optical fiber resonator ring is 0.42 mm. After observing and confirming that the resonant spectra of the micro-nano optical fiber double-ring resonator have been separated spectroscopically, the optical fiber resonator ring is placed on the magnesium fluoride crystal sheet 8 (i.e., the support sheet). Except for the optical fiber ring area (i.e., the first optical fiber resonator ring 4 and the second optical fiber resonator ring 5), silicone gel 9 is dot-coated at other optical fiber parts to complete the fixation of the optical fiber resonator ring (i.e., the first optical fiber resonator ring 4 and the second optical fiber resonator ring 5).
[0027] The working principle of this embodiment is as follows; The transmission characteristics of the micro-nano optical fiber ring (i.e., the first optical fiber resonator ring 4 and the second optical fiber resonator ring 5) are based on the combination of the waveguide ring resonator and the directional coupler theory. The transmission equation of light after passing through the micro-nano optical fiber ring is: (1) In the formula, ——Special expression of complex numbers, ——Optical transmission loss coefficient in the coupling region; ——Coupling coefficient in the coupling region, ——Propagation constant, ——Perimeter of the optical fiber ring.
[0028] βL The physical meaning of is the phase difference generated after the transmitted light propagates one week in the micro-nano optical fiber ring. When the phase difference generated after the transmitted light propagates one week in the micro-nano optical fiber ring is 2mπ - π / 2, the transmission ratio of the micro-nano optical fiber ring reaches the minimum, and ring cavity resonance occurs. Therefore, by solving the equation sin( β L) = -1, the resonance condition of the transmitted light in the micro-nano optical fiber ring can be obtained: (2) In the formula: ——Resonance series, which is an integer.
[0029] The propagation constant β of the micro-nano optical fiber can be expressed as: (3) Wherein: —— The equivalent refractive index of the micro-nano optical fiber. Therefore, the resonant wavelength of the micro-nano optical fiber loop can be obtained as: (4) The first optical fiber resonant loop 4 and the second optical fiber resonant loop 5 are coated with a palladium-silver alloy layer on the outside. The palladium-silver alloy will generate expansion stress under the action of gas, which will cause the loop diameter of the optical fiber resonant loop to change, thereby outputting a drift of the resonant spectral wavelength. The first optical fiber resonant loop 4 is sensitive to both hydrogen and acetylene gases. Since the second optical fiber resonant loop 5 is coated with a molecular sieve material on the outside and hydrogen can pass through while acetylene gas cannot pass through, its output resonant spectrum is only modulated by the hydrogen content. The resonant wavelengths of the micro-nano optical fiber resonant double loop can be respectively expressed as: (5) Wherein: —— The change amount of the resonant wavelength of the first optical fiber resonant loop, —— The change amount of the resonant wavelength of the second optical fiber resonant loop, —— The change amount of the resonant peak caused by hydrogen, —— The change amount of the resonant peak caused by acetylene, —— The hydrogen concentration, —— The acetylene concentration, A and B are sensitivity coefficients, which are fixed values and can be determined by pre-experiment calibration.
[0030] By separating the output spectrum of the optical fiber double-loop resonator (see Figure 4 ), the output resonant wavelengths of the first optical fiber resonant loop and the second optical fiber resonant loop of the optical fiber can be obtained, and the change amounts and of its resonant spectrum can be obtained. According to formula (5), the content information of hydrogen and acetylene can be obtained.
[0031] This embodiment also provides a typical preparation method for the above-mentioned sensor for detecting the content of dissolved hydrogen and acetylene in oil-immersed power equipment, including the following process: The sensing single-mode optical fiber 3 is subjected to melting and tapering to form a cone part 3-1 with a simple diameter and a waist region 3-2 located between the two cone parts 3-1 at both ends on the sensing single-mode optical fiber 3; The first optical fiber resonant ring 4 and the second optical fiber resonant ring 5 are formed in the slender waist area 3-2 by using a knotting method. Then, the two ends of the first optical fiber resonant ring 4 and the two ends of the second optical fiber resonant ring 5 are pre-fixed (subsequent release or non-release is possible, and its main purpose is to prevent the ring diameters of the first optical fiber resonant ring 4 and the second optical fiber resonant ring 5 from changing due to external effects during the preparation process); then, a palladium-silver alloy layer 10 is formed on the surfaces of the first optical fiber resonant ring 4 and the second optical fiber resonant ring 5 by magnetron sputtering, and then a molecular sieve material layer 11 is formed on the surface of the palladium-silver alloy layer 10 on the surface of the second optical fiber resonant ring 5 by molecular self-assembly method; then, a magnesium fluoride crystal sheet 8 is arranged on one side of the first optical fiber resonant ring 4 and the second optical fiber resonant ring 5, and silicone gel 9 is dot-coated at the positions of the two ends of the first optical fiber resonant ring 4 and the two ends of the second optical fiber resonant ring 5 to fix the positions of the two ends of the first optical fiber resonant ring 4 and the two ends of the second optical fiber resonant ring 5 on the magnesium fluoride crystal sheet 8; The large end of the tapered portion 3-1 at one end of the sensing single-mode optical fiber 3 is fusion-spliced to one end of the first single-mode optical fiber 2, and the large end of the tapered portion 3-1 at the other end of the sensing single-mode optical fiber 3 is fusion-spliced to one end of the second single-mode optical fiber 6.
[0032] Obviously, the described embodiments are only partial embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.
[0033] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: the specific implementation manners of the present invention can still be modified or equivalently replaced, and any modification or equivalent replacement without departing from the spirit and scope of the present invention shall be covered by the protection scope of the claims of the present invention.
Claims
1. A sensor for detecting dissolved hydrogen and acetylene content in oil-immersed power equipment, characterized in that: It comprises a first single-mode optical fiber (2), a sensing single-mode optical fiber (3) and a second single-mode optical fiber (6), wherein the first single-mode optical fiber (2), the sensing single-mode optical fiber (3) and the second single-mode optical fiber (6) are connected in sequence; The sensing single-mode optical fiber (3) is a structure formed by melting and taper-drawing a single-mode optical fiber, and the fiber waist region (3-2) of the sensing single-mode optical fiber (3) is formed with a first optical fiber resonant ring (4) and a second optical fiber resonant ring (5) by knotting, the first optical fiber resonant ring (4) and the second optical fiber resonant ring (5) have different ring diameters, and the positions of the two ends of the first optical fiber resonant ring (4) and the two ends of the second optical fiber resonant ring (5) are fixed; A palladium-silver alloy layer (10) is provided on the surface of the first optical fiber resonant ring (4); A palladium-silver alloy layer (10) is provided on the surface of the second optical fiber resonant ring (5), and a molecular sieve material layer (11) is provided on the surface of the palladium-silver alloy layer (10); the gas selection pore size of the molecular sieve material of the molecular sieve material layer (11) is between the sizes of hydrogen and acetylene molecules.
2. A sensor for detecting dissolved hydrogen and acetylene content in oil-immersed power equipment according to claim 1, characterized in that: The diameter of the slender waist region (3-2) is 10μm~15μm.
3. A sensor for detecting dissolved hydrogen and acetylene content in oil-immersed power equipment according to claim 1, characterized in that: The diameter of the first optical fiber resonance ring (4) is 0.2 mm to 1 mm, and the diameter of the second optical fiber resonance ring (5) is 0.2 mm to 1 mm.
4. A sensor for detecting dissolved hydrogen and acetylene content in oil-immersed power equipment according to claim 3, characterized in that: The diameter difference between the first optical fiber resonant ring (4) and the second optical fiber resonant ring (5) is controlled within a range of 0.5 mm to 0.1 mm.
5. A sensor for detecting dissolved hydrogen and acetylene content in oil-immersed power equipment according to claim 1, characterized in that: The thickness of the palladium-silver alloy layer (10) is 100 nm to 300 nm.
6. A sensor for detecting dissolved hydrogen and acetylene content in oil-immersed power equipment according to claim 1, characterized in that: The thickness of the molecular sieve material layer (11) is 50 nm to 100 nm.
7. A sensor for detecting dissolved hydrogen and acetylene content in oil-immersed power equipment according to claim 1, characterized in that: Molecular sieve material uses Cu(FMA)(4,4-bpe) 0.5 The pore window diameter of the molecular sieve material is 3.3Å.
8. A sensor for detecting dissolved hydrogen and acetylene content in oil-immersed power equipment according to claim 1, characterized in that: The positions of the two ends of the first optical fiber resonant ring (4) and the two ends of the second optical fiber resonant ring (5) are fixed in the following manner: The two ends of the first optical fiber resonance ring (4) and the two ends of the second optical fiber resonance ring (5) are fixed on a supporting plate.
9. A method for preparing a sensor for detecting dissolved hydrogen and acetylene content in oil-immersed power equipment according to any one of claims 1 to 8, characterized in that: The process includes the following: The sensing single-mode optical fiber (3) is melt-tapered to form a tapered portion (3-1) with a simple diameter and a fiber waist region (3-2) located between the tapered portions (3-1) at both ends of the sensing single-mode optical fiber (3); A first optical fiber resonance ring (4) and a second optical fiber resonance ring (5) are formed in the fiber waist region (3-2) by a knotting method, and then the positions of the two ends of the first optical fiber resonance ring (4) and the two ends of the second optical fiber resonance ring (5) are fixed; a palladium-silver alloy layer (10) is formed on the surface of the first optical fiber resonance ring (4) and the second optical fiber resonance ring (5) by a magnetron sputtering method, and then a molecular sieve material layer (11) is formed on the surface of the palladium-silver alloy layer (10) on the surface of the second optical fiber resonance ring (5) by a molecular self-assembly method; The large end of the cone (3-1) at one end of the sensing single-mode optical fiber (3) is fused to one end of the first single-mode optical fiber (2), and the large end of the cone (3-1) at the other end of the sensing single-mode optical fiber (3) is fused to one end of the second single-mode optical fiber (6).
10. A device for detecting the content of dissolved hydrogen and acetylene in oil-immersed power equipment, characterized in that: The invention comprises a broadband light source (1), a spectrometer (7) and a sensor for detecting the content of dissolved hydrogen and acetylene in oil-immersed power equipment as claimed in any one of claims 1 to 8, wherein a first single-mode optical fiber (2) is connected to the broadband light source (1), and a second single-mode optical fiber (6) is connected to the spectrometer (7).