Palladium alloy-based hydrogen sensor

Abstract

The invention discloses a palladium alloy-based hydrogen sensor, comprising a shell and a sleeve arranged below the shell, wherein a flange fixedly connected to the bottom of the shell is arranged on one end of the shell, a heat-conducting bracket is threadedly connected to the inside of the sleeve, and a gas-sensitive chip for detecting the hydrogen concentration in transformer oil is installed inside the heat-conducting bracket; the heat-conducting bracket is composed of a base and a plurality of heat-conducting pipes longitudinally arranged on the base, and an annular heat pipe connected to the plurality of heat-conducting pipes is arranged at one end of the plurality of heat-conducting pipes away from the base; a sleeve ring for fixing the annular heat pipe is also arranged inside the sleeve, and the sleeve ring is movably connected to the annular heat pipe; the invention utilizes the heat dissipation effect of the heat-conducting bracket and the condenser to quickly extract the heat of the medium oil around the gas-sensitive chip, thereby ensuring that the gas-sensitive chip works stably in a constant temperature environment and improving the service life of the chip.

Description

Technical Field

[0001] The invention relates to the technical field of sensors, in particular to a hydrogen sensor based on palladium alloy. Background Art

[0002] Transformer failure is the main cause of power plant and substation shutdowns and local power grid accidents. In order to reduce the transformer failure rate, some characteristic gases produced in the transformer oil are usually tested regularly, especially excessive hydrogen content, which will accelerate the aging of the transformer oil, reduce the service life of the insulation material, and fail to achieve good heat dissipation and cooling effects.

[0003] At present, the catalytic adsorption effect of palladium alloy film on hydrogen molecules is used. Usually, the palladium film chip is immersed in transformer oil, which can effectively solve the real-time monitoring of the hydrogen concentration in the transformer oil. However, since the palladium film sensor chip can only work at a constant temperature, and the transformer oil temperature is relatively high, it is easy to cause poor chip stability and reduce the chip life. In order to ensure that the chip works stably at a constant temperature, a temperature control device is usually added to the chip. For example: Patent No. 202010750966.2, a palladium alloy hydrogen sensor, records the addition of a semiconductor cooling and heating plate under the silicon substrate of the palladium film sensor chip to adjust the working temperature of the chip. In order to realize the temperature control operation of the semiconductor cooling and heating plate, it is usually necessary to add a temperature measuring resistor and a temperature control system to the chip, which makes the chip design quite cumbersome.

[0004] Therefore, we propose a method of adding a heat-conducting bracket and a condenser to the probe part of the palladium alloy hydrogen sensor, which can quickly and effectively physically cool the medium oil around the chip, ensuring that the chip works stably in a constant temperature environment. Summary of the invention

[0005] The technical problem to be solved by the present invention is that the palladium alloy hydrogen sensor chip used to monitor the hydrogen concentration in the transformer dielectric oil in the prior art is immersed in the dielectric oil. Since the dielectric oil temperature is higher than the chip working temperature, it is easy to cause poor chip stability and reduce the chip service life. Provided is a palladium alloy-based hydrogen sensor, which utilizes the heat dissipation effect of a heat-conducting bracket and a condenser tube to quickly remove the heat of the dielectric oil around the gas-sensitive chip, thereby ensuring that the gas-sensitive chip works stably in a constant temperature environment and increasing the chip service life;

[0006] The technical solution adopted by the present invention to solve the technical problem is: a hydrogen sensor based on palladium alloy, comprising a shell, and a sleeve arranged below the shell, wherein a flange fixedly connected to the bottom of the shell is arranged at one end of the shell, a heat-conducting bracket is threadedly connected inside the sleeve, and a gas-sensitive chip for detecting the hydrogen concentration in transformer oil is installed inside the heat-conducting bracket;

[0007] The heat-conducting bracket is composed of a base and a plurality of heat-conducting pipes longitudinally mounted on the base, and an annular heat pipe connected to the plurality of heat-conducting pipes is arranged at one end of the plurality of heat-conducting pipes away from the base;

[0008] A sleeve ring for fixing the annular heat pipe is also arranged inside the sleeve, and the sleeve ring is movably connected to the annular heat pipe.

[0009] Furthermore, the outer diameter of the bottom plate at the top of the base is larger than the inner diameter of the sleeve, and the bottom plate portion of the base is arranged above the flange and is closely connected with the contact surface of the flange;

[0010] The base is in a boss structure, with an external thread arranged on the outer periphery of the boss, and an internal thread matching the external thread arranged on the inner periphery of the sleeve corresponding to the boss, and the heat-conducting bracket and the sleeve are threadedly connected via the external thread on the outer periphery of the boss and the internal thread on the inner periphery of the sleeve.

[0011] Furthermore, the base is made of a heat-conducting material, and a mounting groove with an annular structure along the center of a circle is provided on the top chassis of the base away from the flange. A condenser tube with one end extending to the outside of the shell is provided inside the mounting groove, and the condenser tube is distributed in an annular shape and clamped in the mounting groove;

[0012] A wire-passing hole in a strip-shaped structure is arranged in the middle of the top surface of the chassis, and an insulating sealing sleeve is arranged inside the wire-passing hole.

[0013] Furthermore, a heat-conducting substrate is provided at the bottom of the gas-sensing chip, and the gas-sensing chip is fixed on two adjacent heat-conducting tubes in the heat-conducting bracket through the heat-conducting substrate.

[0014] Furthermore, the gas-sensitive chip is a palladium-yttrium alloy thin film chip.

[0015] Furthermore, the heat conducting pipe is a heat conducting copper pipe with a diameter of 3 mm;

[0016] The annular heat pipe is a heat-conducting copper pipe with a diameter of 5 mm.

[0017] Furthermore, a friction rubber sleeve is provided on the outer periphery of the collar, and the collar is fixed to the inner side surface of the sleeve through the friction rubber sleeve;

[0018] A slot matching the annular heat pipe is provided at one end of the inner circumference of the sleeve ring corresponding to the annular heat pipe, and the annular heat pipe is clamped inside the slot;

[0019] A filter screen is also installed inside the collar along the inner circumference of the collar.

[0020] Furthermore, a plurality of symmetrically distributed strip holes are arranged on the outer periphery of one end of the sleeve away from the flange, and both ends of the strip holes are in arc-shaped structures.

[0021] Furthermore, a threaded buckle is provided on the outer periphery of the sleeve near one end of the flange, and the threaded buckle is used for threaded connection with the connector on the transformer oil tank.

[0022] Furthermore, a temperature sensor probe is installed inside the sleeve, and the temperature sensor probe is fixed on the base of the heat-conducting bracket.

[0023] Compared with the prior art, the present invention has the following beneficial effects: the hydrogen sensor based on palladium alloy can quickly remove the heat of the medium oil around the gas-sensitive chip by installing a heat-conducting bracket inside the sleeve and utilizing the heat dissipation effect of the heat-conducting bracket and the condenser tube, thereby ensuring that the gas-sensitive chip works stably in a constant temperature environment and prolonging the service life of the chip; in addition, the heat-conducting bracket also plays a role in fixing the gas-sensitive chip;

[0024] By longitudinally fixing the gas-sensing chip on two adjacent heat pipes inside the heat-conducting bracket, the contact area between the chip and the dielectric oil is increased, thereby improving the hydrogen adsorption capacity;

[0025] By arranging a collar inside the sleeve and clamping the annular heat pipe at the bottom of the heat-conducting bracket into the internal groove of the collar, the collar plays a supporting and protective role for the heat-conducting bracket; the friction rubber sleeve arranged on the outer periphery of the collar effectively utilizes the friction force between the friction rubber sleeve and the contact surface of the inner arm of the sleeve to clamp the collar inside the sleeve, and the collar, the sleeve and the heat-conducting bracket are easy to install and disassemble. The filter screen installed at one end of the collar effectively filters out the impurities in the medium oil;

[0026] By installing a threaded buckle on the outer periphery of the bushing, it is convenient to install the sensor on the connecting head on the bushing of the transformer oil tank, and it is convenient to install and replace the sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the structure of the present invention;

[0028] Figure 2 for Figure 1 A partial enlarged view of the middle part;

[0029] Figure 3 A side view of the gas sensing chip of the present invention installed on a heat dissipation bracket;

[0030] Figure 4 It is a schematic diagram of the three-dimensional structure of the heat dissipation bracket of the present invention;

[0031] Figure 5 It is a schematic diagram of the top surface structure of the base of the present invention.

[0032] In the figure: 1. Shell; 2. Casing; 3. Flange; 4. Heat-conducting bracket; 5. Gas-sensing chip; 6. Ring; 7. Heat-conducting substrate; 8. Connecting wire; 9. Threaded thread; 10. Filter; 11. Circuit board; 12. Battery; 13. Terminal; 14. Fastening screw;

[0033] 21. Internal thread; 22. Strip hole;

[0034] 31. Base; 32. Heat pipe; 33. Ring heat pipe; 34. Condenser; 35. Insulation sealing sleeve;

[0035] 61. Card slot; 62. Friction rubber sleeve;

[0036] 310, chassis; 311, boss; 312, external thread; 313, mounting groove; 314, wire hole. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] See also Figure 1-5 The present invention provides a technical solution: a hydrogen sensor based on palladium alloy, comprising a housing 1, and a sleeve 2 arranged below the housing 1, wherein the sleeve 2 is provided with a flange 3 fixedly connected to the bottom of the housing 1 at one end of the housing, and the flange 3 and the sleeve 2 can be fixed by metal glue gluing or threaded screwing. In this embodiment, the metal glue gluing is used for fixing;

[0039] The sleeve 2 is internally threadedly connected with a heat-conducting bracket 4, and a gas-sensing chip 5 for detecting the hydrogen concentration in the transformer oil is installed inside the heat-conducting bracket 4;

[0040] The heat-conducting bracket 4 is composed of a base 31 and a plurality of heat-conducting pipes 32 longitudinally mounted on the base 31, and a ring-shaped heat pipe 33 connected to the plurality of heat-conducting pipes 32 is arranged at one end of the plurality of heat-conducting pipes 32 away from the base 31;

[0041] A sleeve ring 6 for fixing the annular heat pipe 33 is also disposed inside the sleeve 2 , and the sleeve ring 6 is movably connected to the annular heat pipe 33 .

[0042] See also Figure 1The outer diameter of the bottom plate 310 at the top of the base 31 is larger than the inner diameter of the sleeve 2. The bottom plate portion of the base 31 is arranged above the flange 3 and is in close contact with the contact surface of the flange 3. In order to ensure the sealing between the base 31 and the shell 1, a sealing gasket ring (not shown in the figure) is arranged between the base 31 and the flange 3 in this embodiment, which effectively prevents the liquid oil in the sleeve 2 from penetrating into the interior of the shell 1.

[0043] See also Figure 1 and Figure 4 The base 31 is a boss structure, and an external thread 312 is provided on the outer periphery of the boss 311. The inner circumference of the sleeve 2 corresponding to the boss is provided with an internal thread 21 matching the external thread 312. The heat-conducting bracket 4 and the sleeve 2 are threadedly connected via the external thread 312 on the outer periphery of the boss 311 and the internal thread 21 on the inner circumference of the sleeve 2.

[0044] See also Figure 5 The base 31 is made of a heat-conducting material. In this embodiment, the base 31 is made of a metal copper material with a hollow structure at one end. A mounting groove 313 with an annular structure along the center of a circle is provided on the bottom plate 310 at the top of the base 31 away from the flange 3. A condenser 34 with one end extending to the outside of the housing 1 is provided inside the mounting groove 313. The condenser 34 is distributed in an annular shape and is clamped in the mounting groove 313.

[0045] A strip-shaped wire hole 314 is disposed in the middle of the top surface of the chassis 310 , and an insulating sealing sleeve 35 is disposed inside the wire hole 314 .

[0046] See also Figure 3 A heat-conducting substrate 7 is provided at the bottom of the gas-sensing chip 5, and the gas-sensing chip 5 is fixed on two adjacent heat-conducting tubes 32 in the heat-conducting bracket 4 through the heat-conducting substrate 7. In this embodiment, the heat-conducting substrate 7 and the heat-conducting tubes 32 are fixed by metal glue, and the heat-conducting bracket 4 also plays a role in fixing the gas-sensing chip 5.

[0047] See also Figure 1 The gas-sensitive chip 5 is a palladium-yttrium alloy thin film chip. In this embodiment, the gas-sensitive chip 5 uses a palladium-yttrium alloy thin film with mature technology to catalyze the decomposition of hydrogen in the transformer oil. The decomposed hydrogen molecules are adsorbed on the surface of the alloy film. Under the catalytic action of the palladium-yttrium alloy thin film, the hydrogen molecules are decomposed into two hydrogen atoms. The hydrogen atoms diffuse into the interior of the palladium-yttrium alloy lattice, causing lattice expansion and phase change, resulting in a change in the conductivity of the alloy film, thereby realizing the measurement of hydrogen concentration.

[0048] In this embodiment, the palladium-yttrium alloy thin film chip is connected to the connector on the circuit board 11 inside the shell through the connecting wire 8. A large-capacity battery 12 is arranged inside the shell 1 to facilitate powering the sensor when the external power is off.

[0049] See also Figure 4 The heat conducting pipe 32 is a heat conducting copper pipe with a diameter of 3 mm;

[0050] The annular heat pipe 33 is a heat-conducting copper pipe with a diameter of 5 mm.

[0051] See also Figure 1 and Figure 2 The outer periphery of the collar 6 is provided with a friction rubber sleeve 62, and the collar 6 is fixed to the inner side of the sleeve 2 through the friction rubber sleeve 62;

[0052] The inner circumference of the sleeve ring 6 corresponds to one end of the annular heat pipe 33 and is provided with a slot 61 matching the annular heat pipe 33. The annular heat pipe 33 is clamped in the slot 61.

[0053] A filter screen 10 is also installed inside the collar 6 along the inner circumference of the collar. The purpose of providing the filter screen 10 in this embodiment is to filter out impurities in the medium oil and avoid damaging the chip.

[0054] See also Figure 1 A plurality of symmetrically distributed strip holes 22 are provided on the outer periphery of one end of the sleeve 2 away from the flange 3 , and both ends of the strip holes 22 are arc-shaped structures.

[0055] See also Figure 1 A threaded buckle 9 is arranged on the outer periphery of the sleeve 2 near one end of the flange 3, and the threaded buckle 9 is used for threaded connection with the connector on the transformer oil tank. In this embodiment, the threaded buckle 9 is arranged on the outer periphery of the sleeve 2 to facilitate installation of the sensor on the sleeve of the transformer oil tank, and installation and disassembly are convenient.

[0056] A temperature sensor probe (not shown in the figure) is also installed inside the sleeve 2 , and the temperature sensor probe is fixed on the base 31 of the heat-conducting bracket 4 .

[0057] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A hydrogen sensor based on palladium alloy, characterized in that: It comprises a shell, and a sleeve arranged below the shell, wherein a flange fixedly connected to the bottom of the shell is arranged at one end of the shell, a heat-conducting bracket is threadedly connected inside the shell, and a gas-sensitive chip for detecting the hydrogen concentration in the transformer oil is installed inside the heat-conducting bracket; The heat-conducting bracket is composed of a base and a plurality of heat-conducting pipes longitudinally mounted on the base, and an annular heat pipe connected to the plurality of heat-conducting pipes is arranged at one end of the plurality of heat-conducting pipes away from the base; A sleeve ring for fixing the annular heat pipe is also provided inside the sleeve, and the sleeve ring is movably connected to the annular heat pipe; The outer diameter of the bottom plate at the top of the base is larger than the inner diameter of the sleeve, and the bottom plate portion of the base is arranged above the flange and is closely connected with the contact surface of the flange; The base is a boss structure, an external thread is provided on the outer periphery of the boss, an internal thread matching the external thread is provided on the inner periphery of the sleeve corresponding to the boss, and the heat-conducting bracket and the sleeve are threadedly connected via the external thread on the outer periphery of the boss and the internal thread on the inner periphery of the sleeve; The base is made of a heat-conducting material, and a mounting groove with an annular structure along the center of a circle is arranged on the top chassis of the base away from the flange. A condenser tube with one end extending to the outside of the shell is arranged inside the mounting groove, and the condenser tube is distributed in an annular shape and clamped in the mounting groove; A wire-passing hole in a strip-shaped structure is provided in the middle of the top surface of the chassis, and an insulating sealing sleeve is provided inside the wire-passing hole; A heat-conducting substrate is arranged at the bottom of the gas-sensing chip, and the gas-sensing chip is fixed on two adjacent heat-conducting tubes in the heat-conducting bracket through the heat-conducting substrate.

2. The palladium alloy-based hydrogen sensor according to claim 1, characterized in that: The gas-sensitive chip is a palladium-yttrium alloy thin film chip.

3. The palladium alloy-based hydrogen sensor according to claim 1, characterized in that: The heat conducting pipe is a heat conducting copper pipe with a diameter of 3 mm; The annular heat pipe is a heat-conducting copper pipe with a diameter of 5 mm.

4. The palladium alloy-based hydrogen sensor according to claim 1, characterized in that: A friction rubber sleeve is arranged on the outer periphery of the sleeve ring, and the sleeve ring is fixed to the inner side surface of the sleeve through the friction rubber sleeve; A slot matching the annular heat pipe is provided at one end of the inner circumference of the sleeve ring corresponding to the annular heat pipe, and the annular heat pipe is clamped inside the slot; A filter screen is also installed inside the collar along the inner circumference of the collar.

5. The palladium alloy-based hydrogen sensor according to claim 1, characterized in that: A plurality of symmetrically distributed strip holes are arranged on the outer periphery of one end of the sleeve away from the flange, and both ends of the strip holes are in arc-shaped structures.

6. The palladium alloy-based hydrogen sensor according to claim 1, characterized in that: A threaded buckle is arranged on the outer periphery of the sleeve near one end of the flange, and the threaded buckle is used for threaded connection with the connector on the transformer oil tank.

7. The palladium alloy-based hydrogen sensor according to claim 1, characterized in that: A temperature sensor probe is also installed inside the sleeve, and the temperature sensor probe is fixed on the base of the heat-conducting bracket.

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