An inflatable ring main unit and a method for inflating the same

Abstract

This invention discloses an inflatable ring main unit and its inflation method, including a load switch operating cabinet, a protective door, an air box, and a live component mechanism. This invention relates to the field of power supply technology. The inflatable ring main unit and its inflation method, through the cooperation of the air box, the air inlet mechanism, the manifold box, and the directional self-adjusting mechanism, allow the air inlet mechanism to adaptively adjust the sulfur hexafluoride (SF6) inlet flow rate according to the real-time gas pressure inside the air box. The inflation is performed in three stages: low pressure and low flow rate, high flow rate in the middle stage, and slow inflation with a low flow rate near the rated pressure. This avoids eddy current disturbances and localized negative pressure caused by the initial high-speed airflow, and also prevents pressure overshoot from damaging the air box's sealing structure. Simultaneously, with the cooperation of the directional self-adjusting mechanism and the manifold box, the airflow is autonomously driven and dynamically changes the gas flow direction, ensuring uniform gas distribution within the air box. This avoids direct impact on the live component mechanism, improving insulation reliability, reducing discharge risk, and enabling automatic control throughout the process, effectively improving the efficiency of power operation and maintenance.

Description

Technical Field

[0001] This invention relates to the field of power supply technology, specifically to an inflatable ring main unit and its inflation method. Background Technology

[0002] Gas-insulated ring main units are core equipment for terminal power distribution in power systems. With their excellent insulation performance and compact structure, they are widely used in urban power grids, industrial parks, and power supply systems for various industrial users. They are key nodes for ensuring stable and continuous power supply and distribution. They are deeply embedded in large-scale power grid security and defense systems and intelligent dispatch systems, integrating control, protection, and power distribution functions. They are an indispensable and important piece of equipment in smart grids. They typically use sulfur hexafluoride gas as the insulating medium, and their operational reliability directly affects the safety of downstream power consumption and the overall stability of the power grid.

[0003] Referring to the patent application CN221447918U, an inflatable ring main unit is disclosed. A side panel is used to completely cover the sides of the cabinet and the gas chamber, which not only strengthens the overall strength of the ring main unit and controls the deformation of the gas chamber, resulting in an aesthetically pleasing appearance, but also, in conjunction with a first sealing plate, protects the periphery of the gas chamber, further enhancing its strength. A cavity is formed between the side panel and the gas chamber surface, and an insulating board is placed inside this cavity. The insulating board not only provides excellent flame retardant effect during the gas chamber arc test, but also enhances the strength of the gas chamber. During the gas chamber inflation process, the gas chamber is less prone to deformation, and the switches inside the gas chamber will not become misaligned due to gas chamber deformation, thus affecting the overall performance of the switching equipment.

[0004] A comprehensive analysis of the above-mentioned patents reveals the following shortcomings: Existing gas-filled ring main units and their filling methods suffer from several drawbacks. During the process of filling the gas tank with sulfur hexafluoride gas using an external filling tank, the filling flow rate is difficult to adaptively adjust with changes in the gas pressure inside the tank. This easily leads to initial high-speed airflow causing eddy current disturbances and localized negative pressure. When approaching the rated pressure, pressure overshoot damages the sealing structure. Furthermore, it is difficult to adjust the gas flow direction in real time; a fixed gas flow direction can easily cause the gas to directly impact the live components inside the tank, resulting in difficulty in quickly and evenly distributing the gas within the tank and a high risk of partial discharge. Therefore, it is necessary to provide a gas-filled ring main unit and its filling method to solve the above-mentioned technical problems. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides an inflatable ring main unit and its inflation method. This solves the problems encountered when using an external inflation tank to fill the gas tank with sulfur hexafluoride gas. Specifically, the inflation flow rate is difficult to adaptively adjust with changes in gas pressure within the gas tank, easily leading to initial high-speed airflow causing eddy current disturbances and localized negative pressure. Pressure overshoot near the rated pressure can damage the sealing structure. Furthermore, it is difficult to adjust the gas flow direction in real time; a fixed gas flow direction can easily cause direct impact on live components within the gas tank, resulting in difficulty in rapid and uniform gas distribution and a high risk of partial discharge.

[0006] To achieve the above objectives, the present invention provides the following technical solution: an inflatable ring main unit, comprising a load switch operating cabinet, a protective door, an air box, and a live component mechanism, wherein the protective door is located on the right side of the load switch operating cabinet, the air box is located on the top left side of the load switch operating cabinet, and the live component mechanism is located inside the air box, and further comprising: The inlet mechanism is used to introduce sulfur hexafluoride gas stored in an external gas tank into the gas box, and adaptively adjust the gas inlet flow rate according to the gas pressure change in the gas box. The inlet mechanism is located at the bottom of the gas box and extends through the top of the load switch operating cabinet. The manifold is used to collect and guide the sulfur hexafluoride gas introduced through the inlet end mechanism. The manifold is fixedly installed at the bottom of the inner cavity of the gas box. A directional self-adjusting mechanism is used to regulate and change the output flow direction of sulfur hexafluoride gas in the gas exchange box in real time. The directional self-adjusting mechanism is set inside the gas exchange box. A pressure sensor is fixedly installed inside the gas box. An exhaust valve is set on the top of the gas box. A pressure relief valve is set on the left side of the gas box.

[0007] Preferably, the air intake mechanism includes a receiving box, the top of which is fixedly disposed at the bottom of the air box, an inflation valve is fixedly disposed through the right side of the receiving box, an air guide pipe assembly is disposed on the top right side of the inner cavity of the receiving box, an air intake volume self-adjusting assembly is disposed on the left side of the inner cavity of the receiving box, limit plates are fixedly disposed on the upper and lower parts of the left side of the inner cavity of the receiving box, and a rotating shaft is rotatably disposed between the left and right side walls of the inner cavity of the receiving box, a worm gear sleeve is fixedly sleeved on the right outer wall of the rotating shaft, and a gear is fixedly sleeved on the left outer wall of the rotating shaft.

[0008] Preferably, the air guide tube assembly includes an outer tube, the top of which is fixedly disposed on the top right side of the inner cavity of the receiving box. The interior of the outer tube is connected to the interior of the air box. A support plate is fixedly disposed between the front and rear walls of the top of the inner cavity of the outer tube. An external air inlet is provided on the lower right side of the outer tube. An annular sleeve is fixedly fitted on the lower outer wall of the outer tube. The left end of the inflation valve is fixedly connected to the right side of the annular sleeve. The external air inlet is located inside the annular sleeve.

[0009] Preferably, a hollow shielding post is rotatably disposed between the bottom sidewalls of the inner cavity of the outer tube. An inner air inlet is provided at the front of the hollow shielding post, and the position of the inner air inlet corresponds to that of the outer air inlet. A short shaft that rotatably passes through the bottom of the outer tube is fixedly disposed at the middle of the bottom of the hollow shielding post. A worm gear is fixedly disposed at the bottom of the short shaft. The front of the worm gear meshes with a worm sleeve. A retaining ring located at the upper part of the hollow shielding post is fixedly disposed between the upper sidewalls of the inner cavity of the outer tube.

[0010] Preferably, the air intake self-adjusting component includes a cylinder, the top of which is fixedly connected to the top of the inner cavity of the receiving box, the interior of which is connected to the interior of the air box, a piston block is slidably disposed between the inner cavity sidewalls of the cylinder, and a vertical rod is fixedly disposed in the middle of the bottom of the piston block.

[0011] Preferably, the bottom of the vertical rod slides through the bottom of the cylinder and is fixedly provided with a rack through the bottom plate. The rack meshes with a gear and slides through the interior of the two limiting plates. Several springs are evenly fixedly provided around the bottom outer side of the piston block, and the bottom of the springs is fixedly connected to the bottom of the inner cavity of the cylinder.

[0012] Preferably, the direction self-adjusting mechanism includes a support rod, which is fixedly connected between the upper left and right side walls of the inner cavity of the junction box. Several adjusting vertical plates are uniformly rotated and sleeved on the outside of the support rod from left to right. A square push rod located directly below the adjusting vertical plates slides through between the left and right side walls of the junction box.

[0013] Preferably, a support rod is fixedly installed at the top of the square push rod and on both sides of each adjusting vertical plate, a square frame is fixedly installed at the bottom center of the square push rod, a reducer is installed directly below the square frame, and the front and rear walls of the reducer are fixedly connected to the inner wall of the junction box by connecting rods.

[0014] Preferably, the input end of the reducer is fixedly connected to a vertical shaft, the bottom of the vertical shaft rotates through the bottom of the support plate and is fixedly equipped with a fan, the fan is located in the upper part of the inner cavity of the outer sleeve, and the output end of the reducer is fixedly equipped with a drive wheel, the left and right ends of the drive wheel are in contact with the left and right side walls of the inner cavity of the square frame, respectively.

[0015] This invention also provides an inflation method for an inflatable ring main unit, which includes the following steps: Step 1: Open the protective door to expose the air inlet mechanism. Connect the external gas tank to the air inlet mechanism so that the sulfur hexafluoride gas stored in the external gas tank is introduced into the gas box through the air inlet mechanism and the manifold box. As the gas pressure in the gas box changes, the air inlet mechanism adaptively adjusts the gas intake flow rate. Step 2: In the initial low-pressure stage of inflation, sulfur hexafluoride gas enters at a low flow rate through a small throttling area, avoiding eddy current disturbances caused by high-speed airflow under high vacuum. In the middle stage of inflation, as the internal pressure of the gas box increases, the inlet mechanism automatically increases the flow area, increasing the inflation speed without causing impact and shortening the inflation operation time. When approaching the rated pressure, the inlet mechanism automatically reduces the flow area to achieve stable pressure and slow inflation, avoiding pressure overshoot that could cause instantaneous stress impact on the gas box sealing structure. Step 3: The sulfur hexafluoride gas introduced through the inlet mechanism first enters the manifold box. The directional self-adjusting mechanism is driven to work as the sulfur hexafluoride gas flows, thereby dynamically and continuously changing the gas flow direction of the sulfur hexafluoride gas in the manifold box to the gas tank. When the pressure sensor detects that the pressure in the gas tank has reached the rated value, the external gas tank valve is closed, the connection between the inlet mechanism and the external gas tank is disconnected, the protective door is closed, and the inflation operation is completed.

[0016] Beneficial effects This invention provides an inflatable ring main unit and its inflation method. Compared with the prior art, it has the following advantages: 1. An inflatable ring main unit and its inflation method, wherein the inflatable ring main unit and its inflation method are characterized by the cooperation of an air box, an air inlet mechanism, a manifold box, and a directional self-adjusting mechanism. The air inlet mechanism can adaptively adjust the sulfur hexafluoride inlet flow rate according to the real-time air pressure in the air box, and the inflation is carried out in three stages: low pressure and low flow rate, high flow rate in the middle stage, and slow inflation with low flow rate near the rated pressure. This can avoid eddy current disturbance and local negative pressure caused by the initial high-speed airflow, and also prevent pressure overshoot from damaging the air box sealing structure. At the same time, with the cooperation of the directional self-adjusting mechanism and the manifold box, the airflow is autonomously driven and dynamically changes the gas flow direction, so that the gas distribution in the air box is uniform, avoiding direct impact on the live parts, improving insulation reliability, reducing discharge risk, and automatically controlling the entire process, which can effectively improve the efficiency of power operation and maintenance.

[0017] 2. An inflatable ring main unit and its inflation method, through the cooperation of the air guide pipe assembly, the air intake self-adjusting assembly, the worm sleeve and the gear, can achieve phased intelligent flow control. In the initial low-pressure stage of inflation, the air box is close to a vacuum, the overlap area between the inner air inlet and the outer air inlet is small, and the gas enters at a low flow rate, which can avoid eddy current disturbance and local negative pressure. In the middle stage, as the pressure in the air box increases, the piston block moves down to drive the rack, gear, worm sleeve and worm wheel to work, which can automatically expand the air intake channel and increase the inflation speed. When the pressure approaches the rated pressure, the air intake channel can automatically shrink to achieve stable pressure and slow inflation to avoid pressure overshoot. No electrical control is required during the flow control process, resulting in a low failure rate and stronger stability.

[0018] 3. An inflatable ring main unit and its inflation method, wherein by adjusting the interaction between the vertical plate, support rod, square frame, fan and drive wheel, the gas enters the junction box through the outer sleeve. The airflow drives the fan to rotate, and through the vertical shaft, reducer and drive wheel, drives the square push rod and support rod to move back and forth, so that the adjusting vertical plate deflects back and forth around the bearing rod within a set angle, thereby changing the direction of gas output in real time. This avoids the gas from directly impacting the live parts, and makes the pressure and density of sulfur hexafluoride gas in the gas box uniformly distributed. The uniform gas distribution can stabilize the insulation performance around the live parts, greatly reduce the risk of partial discharge and insulation failure, and significantly improve the safety and reliability of the ring main unit operation.

[0019] 4. An inflatable ring main unit and its inflation method, wherein the directional self-adjusting mechanism can use the inflation airflow as a power source throughout the process and rely on the airflow to autonomously drive the flow direction adjustment work. This self-driving design makes the overall structure simpler and more compact, with no additional energy consumption, effectively reducing operation and maintenance costs.

[0020] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0021] Figure 1 This is a perspective view of the present invention; Figure 2 This is a perspective view of the gas box of the present invention; Figure 3 This is a cross-sectional perspective view of the air box of the present invention; Figure 4 This is an assembly diagram of the air intake mechanism, the manifold box, and the directional self-adjusting mechanism of the present invention; Figure 5 This is a cross-sectional perspective view of the air intake mechanism and the manifold box of the present invention; Figure 6 This is an exploded view of the air intake mechanism, the manifold box, and the directional self-adjusting mechanism of the present invention; Figure 7 This is a cross-sectional perspective view of the air intake mechanism of the present invention; Figure 8 This is a first sectional perspective view of the air duct assembly of the present invention; Figure 9 This is a second sectional perspective view of the air duct assembly of the present invention; Figure 10 This is a cross-sectional perspective view of the intake volume self-adjusting component of the present invention; Figure 11 This is a perspective view of the orientation self-adjusting mechanism of the present invention; Figure 12 This is a perspective view of the square frame of the present invention; Figure 13 This is a perspective view of the drive wheel of the present invention.

[0022] In the diagram: 1. Load switch control cabinet; 2. Protective door; 3. Gas box; 4. Live component mechanism; 5. Air inlet mechanism; 51. Receiving box; 52. Inflation valve; 53. Air duct assembly; 531. Outer sleeve; 532. External air inlet; 533. Annular sleeve; 534. Hollow shielding column; 535. Internal air inlet; 536. Short shaft; 537. Worm gear; 54. Air intake self-adjusting assembly; 541 542. Cylinder; 543. Piston block; 544. Vertical rod; 545. Spring; 546. Rack; 55. Limiting plate; 56. Rotating shaft; 57. Worm sleeve; 58. Gear; 6. Connecting box; 79. Directional self-adjusting mechanism; 70. Bearing rod; 71. Adjusting vertical plate; 72. Square push rod; 73. Support rod; 74. Square frame; 75. Reducer; 76. Vertical shaft; 77. Fan; 78. Drive wheel. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] This invention provides two technical solutions: like Figures 1 to 4 The first embodiment is shown: an inflatable ring main unit, including a load switch operating cabinet 1, a protective door 2, an air box 3, and a live component mechanism 4. The protective door 2 is located on the right side of the load switch operating cabinet 1, the air box 3 is located on the top left side of the load switch operating cabinet 1, and the live component mechanism 4 is located inside the air box 3. It also includes: The inlet mechanism 5 is used to introduce sulfur hexafluoride gas stored in an external gas tank into the gas box 3, and adaptively adjust the gas inlet flow rate according to the gas pressure change in the gas box 3. The inlet mechanism 5 is located at the bottom of the gas box 3 and extends through the top of the load switch operating cabinet 1. The collection box 6 is used to collect and guide the sulfur hexafluoride gas introduced through the air inlet mechanism 5. The collection box 6 is fixedly installed at the bottom of the inner cavity of the gas box 3. The directional self-adjusting mechanism 7 is used to regulate and change the output flow direction of sulfur hexafluoride gas in the manifold 6 in real time. The directional self-adjusting mechanism 7 is set inside the manifold 6. A pressure sensor is fixedly installed inside the gas box 3. An exhaust valve is installed on the top of the gas box 3. A pressure relief valve is installed on the left side of the gas box 3.

[0025] Through the cooperation of the gas box 3, the air inlet mechanism 5, the junction box 6, and the directional self-adjusting mechanism 7, the air inlet mechanism 5 can adaptively adjust the sulfur hexafluoride inlet flow rate according to the real-time gas pressure in the gas box 3. It charges in three stages: low pressure and low flow rate, high flow rate in the middle stage, and slow charging with low flow rate near the rated pressure. This can avoid eddy disturbances and local negative pressure caused by the initial high-speed airflow, and also prevent pressure overshoot from damaging the sealing structure of the gas box 3. At the same time, with the cooperation of the directional self-adjusting mechanism 7 and the junction box 6, the airflow is autonomously driven and dynamically changes the gas flow direction, so that the gas distribution in the gas box 3 is uniform, avoiding direct impact on the live parts mechanism 4, improving insulation reliability, reducing discharge risk, and automatically controlling the entire process, effectively improving the efficiency of power operation and maintenance.

[0026] like Figures 5 to 13The second embodiment is shown, and its main difference from the first embodiment is that: an inflatable ring main unit, the air inlet mechanism 5 includes a receiving box 51, the top of the receiving box 51 is fixedly set at the bottom of the air box 3, an inflation valve 52 is fixedly passed through the right side of the receiving box 51, the inflation valve 52 is the prior art known to those skilled in the art, an air guide pipe assembly 53 is provided on the top right side of the inner cavity of the receiving box 51, an air intake volume self-adjusting assembly 54 is provided on the left side of the inner cavity of the receiving box 51, limit plates 55 are fixedly set on the upper and lower parts of the left side of the inner cavity of the receiving box 51, a rotating shaft 56 is rotatably arranged between the left and right side walls of the inner cavity of the receiving box 51, a worm gear sleeve 57 is fixedly sleeved on the right outer wall of the rotating shaft 56, and a worm gear sleeve 57 is fixedly sleeved on the left outer wall of the rotating shaft 56. The assembly includes a gear 58 and an air duct assembly 53, which includes an outer sleeve 531. The top of the outer sleeve 531 is fixedly located on the right side of the inner cavity of the receiving box 51. The interior of the outer sleeve 531 is connected to the interior of the air box 3. A support plate is fixedly installed between the front and rear walls of the top of the inner cavity of the outer sleeve 531. An external air inlet 532 is opened at the lower right side of the outer sleeve 531. An annular sleeve 533 is fixedly fitted on the lower outer wall of the outer sleeve 531. The left end of the inflation valve 52 is fixedly connected to the right side of the annular sleeve 533. The external air inlet 532 is located inside the annular sleeve 533. A hollow baffle post 534 is rotatably installed between the bottom side walls of the inner cavity of the outer sleeve 531. An internal air inlet 535 is opened at the front of the hollow baffle post 534. The internal air inlet 535 and the external air inlet 534 are connected. Corresponding to position 32, a short shaft 536 is fixedly installed at the bottom center of the hollow shielding column 534, which rotates through the bottom of the outer sleeve 531. A worm gear 537 is fixedly installed at the bottom of the short shaft 536. The front part of the worm gear 537 meshes with the worm sleeve 57. A retaining ring located on the upper part of the hollow shielding column 534 is fixedly installed between the upper side walls of the inner cavity of the outer sleeve 531. The air intake self-adjusting assembly 54 includes a cylinder 541. The top of the cylinder 541 is fixedly connected to the top of the inner cavity of the receiving box 51. The interior of the cylinder 541 is connected to the interior of the air box 3. A piston block 542 is slidably installed between the inner side walls of the cylinder 541. A vertical rod 543 is fixedly installed at the bottom center of the piston block 542. The bottom of the vertical rod 543 slides through the cylinder 541. A rack 545 is fixedly installed at the bottom of the 41 via a base plate. The rack 545 meshes with a gear 58 and slides between the interiors of two limiting plates 55. A through groove is provided on the left side of the bottom of the receiving box 51, directly below the base plate. Several springs 544 are evenly fixedly installed around the bottom outer edge of the piston block 542. The bottom of the springs 544 is fixedly connected to the bottom of the inner cavity of the cylinder 541. The directional self-adjusting mechanism 7 includes a bearing rod 71, which is fixedly connected between the upper left and right side walls of the inner cavity of the connecting box 6. Several adjusting vertical plates 72 are evenly rotated and sleeved on the outside of the bearing rod 71 from left to right. A square push rod 73 located directly below the adjusting vertical plate 72 slides through between the left and right side walls of the connecting box 6.A support rod 74 is fixedly installed at the top of the square push rod 73 and on both sides of each adjusting vertical plate 72. A square frame 75 is fixedly installed at the bottom center of the square push rod 73. A reducer 76 is installed directly below the square frame 75. The front and rear walls of the reducer 76 are fixedly connected to the inner wall of the junction box 6 by connecting rods. A vertical shaft 77 is fixedly connected to the input end of the reducer 76. The bottom of the vertical shaft 77 rotates through the bottom of the support plate and is fixedly installed with a fan 78. The fan 78 is located in the upper part of the inner cavity of the outer sleeve 531. A drive wheel 79 is fixedly installed at the output end of the reducer 76. The left and right ends of the drive wheel 79 are in contact with the left and right side walls of the inner cavity of the square frame 75, respectively.

[0027] Through the cooperation of the air guide tube assembly 53, the air intake self-adjusting assembly 54, the worm sleeve 57, and the gear 58, phased intelligent flow control can be achieved. In the initial low-pressure stage of inflation, the air box 3 is close to a vacuum, and the overlapping area of ​​the inner air inlet 535 and the outer air inlet 532 is small, allowing the gas to enter at a low flow rate, which can avoid eddy current disturbance and local negative pressure. In the middle stage, as the pressure in the air box 3 increases, the piston block 542 moves down, driving the rack 545, gear 58, worm sleeve 57, and worm wheel 537 to work, which can automatically expand the air intake channel and increase the inflation speed. When approaching the rated pressure, the air intake channel can automatically shrink, achieving stable pressure and slow inflation to avoid pressure overshoot. No electrical control is required during the flow control process, resulting in a low failure rate and stronger stability. By adjusting the cooperation of the vertical plate 72, support rod 74, square frame 75, fan 78, and drive wheel 79, the gas passes through the outer tube. During the process of 531 entering the junction box 6, the airflow drives the fan 78 to rotate, which in turn drives the square push rod 73 and the support rod 74 to move back and forth through the vertical shaft 77, reducer 76, and drive wheel 79. This causes the adjusting vertical plate 72 to deflect back and forth around the bearing rod 71 within a set angle, thereby changing the direction of gas output in real time. This avoids the gas from directly impacting the live component mechanism 4, ensuring that the pressure and density of sulfur hexafluoride gas in the gas box 3 are evenly distributed. The uniform gas distribution can stabilize the insulation performance around the live component mechanism 4, significantly reducing the risk of partial discharge and insulation failure, and significantly improving the safety and reliability of the ring main unit operation. The self-adjusting direction mechanism 7 can use the airflow as a power source throughout the process and rely on the airflow to autonomously drive the flow direction adjustment. This self-drive design makes the overall structure simpler and more compact, with no additional energy consumption, effectively reducing operation and maintenance costs.

[0028] This invention also provides an inflation method for an inflatable ring main unit, which includes the following steps: Step 1: Open the protective door 2 to expose the air inlet mechanism 5 inside the load switch operating cabinet 1. Seal the external sulfur hexafluoride filling tank with the filling valve 52 to ensure no leakage at the interface. Open the external sulfur hexafluoride filling tank valve. The sulfur hexafluoride gas enters the annular sleeve 533 through the filling valve 52, and then enters the upper inner cavity of the outer sleeve 531 through the outer air inlet 532 and the inner air inlet 535. After that, it is input into the gas box 3 through the manifold box 6. During the filling process, the air intake self-adjusting component 54 automatically adjusts the air intake flow rate according to the real-time air pressure of the gas box 3. Step 2: In the initial low-pressure stage of inflation, the air box 3 is close to a vacuum with extremely low pressure. The piston block 542 is in a high position under the action of the spring 544. At this time, the overlapping area of ​​the inner air inlet 535 and the outer air inlet 532 is small, and the throttling area is small. The gas enters the air box 3 at a low flow rate, avoiding high-speed airflow from causing eddy current disturbance, local negative pressure, or component vibration in the air box 3. In the middle stage of inflation, the pressure in the air box 3 gradually increases. The gas pressure pushes the piston block 542 downward to compress the spring 544. The vertical rod 543 drives the rack 545 to move downward, which in turn drives the gear 58 to rotate. The rotating shaft 56 and the worm sleeve 57 rotate accordingly. The worm sleeve 57 drives the worm wheel 537 and the hollow shield. As the column 534 rotates, the overlapping area of ​​the inner air inlet 535 and the outer air inlet 532 gradually increases, and the air intake channel gradually opens completely, increasing the inflation speed and shortening the operation time. When the pressure approaches the rated pressure, the pressure inside the air box 3 approaches the rated value, the piston block 542 moves down to a low position, the rack 545 moves down accordingly, driving the gear 58 to rotate, and the rotating shaft 56 and the worm sleeve 57 rotate accordingly. The worm sleeve 57 drives the worm wheel 537 and the hollow shield column 534 to rotate, and the overlapping area of ​​the inner air inlet 535 and the outer air inlet 532 gradually decreases, and the air intake flow rate automatically decreases. The rated pressure is approached by slow inflation with a small flow rate, avoiding instantaneous pressure overshoot and protecting the air box 3 from instantaneous impact damage. Step 3: As sulfur hexafluoride gas enters the junction box 6 through the outer sleeve 531, the airflow acts on the fan 78 and drives it to rotate. This rotational power is transmitted to the reducer 76 via the vertical shaft 77. After deceleration, the drive wheel 79 rotates. The rotating drive wheel 79 then drives the square frame 75 to reciprocate linearly in the left and right direction. The square frame 75 then drives the square push rod 73 and the support rod 74 to move horizontally in sync. The two adjacent support rods 74 of each adjusting vertical plate 72 cooperate with each other to deflect the adjusting vertical plate 72 around the bearing rod 71 within a set angle, thereby changing the output flow direction of the gas in the junction box 6 in real time and continuously, realizing the dynamic and continuous adjustment of the gas flow direction, avoiding local direct rush and uneven pressure, ensuring uniform gas density around the live component mechanism 4, and improving insulation reliability. When the pressure sensor detects that the pressure in the gas tank 3 has reached the rated value, the external gas tank valve is closed, the connection between the gas valve 52 and the external gas tank is disconnected, and the protective door 2 is closed to complete the gas filling operation.

[0029] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0030] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An inflatable ring main unit comprising a load switch operating cabinet, a shield door, an air tank, and a live part mechanism, the shield door being provided at the right side of the load switch operating cabinet, the air tank being provided at the left side top of the load switch operating cabinet, and the live part mechanism being provided inside the air tank, characterized in that, Also includes: The inlet mechanism is used to introduce sulfur hexafluoride gas stored in an external gas tank into the gas box, and adaptively adjust the gas inlet flow rate according to the gas pressure change in the gas box. The inlet mechanism is located at the bottom of the gas box and extends through the top of the load switch operating cabinet. The manifold is used to collect and guide the sulfur hexafluoride gas introduced through the inlet end mechanism. The manifold is fixedly installed at the bottom of the inner cavity of the gas box. A directional self-adjusting mechanism is used to regulate and change the output flow direction of sulfur hexafluoride gas in the gas exchange box in real time. The directional self-adjusting mechanism is set inside the gas exchange box. A pressure sensor is fixedly installed inside the gas box. An exhaust valve is set on the top of the gas box. A pressure relief valve is set on the left side of the gas box.

2. An inflatable ring main unit according to claim 1, characterized in that: The air intake mechanism includes a receiving box, the top of which is fixedly mounted on the bottom of the air box. An inflation valve is fixedly passed through the right side of the receiving box. An air guide pipe assembly is provided on the top right side of the inner cavity of the receiving box. An air intake volume self-adjusting assembly is provided on the left side of the inner cavity of the receiving box. Limit plates are fixedly mounted on the upper and lower parts of the left side of the inner cavity of the receiving box. A rotating shaft is rotatably mounted between the left and right side walls of the inner cavity of the receiving box. A worm gear sleeve is fixedly fitted on the right outer wall of the rotating shaft, and a gear is fixedly fitted on the left outer wall of the rotating shaft.

3. An inflatable ring main unit according to claim 2, characterized in that: The air guide tube assembly includes an outer tube, the top of which is fixedly disposed on the top right side of the inner cavity of the receiving box. The interior of the outer tube is connected to the interior of the air box. A support plate is fixedly disposed between the front and rear walls of the top of the inner cavity of the outer tube. An external air inlet is provided on the lower right side of the outer tube. An annular sleeve is fixedly fitted on the lower outer wall of the outer tube. The left end of the inflation valve is fixedly connected to the right side of the annular sleeve. The external air inlet is located inside the annular sleeve.

4. An inflatable ring main unit according to claim 3, characterized in that: A hollow shielding column is rotatably disposed between the bottom sidewalls of the inner cavity of the outer tube. An inner air inlet is provided at the front of the hollow shielding column, and the position of the inner air inlet corresponds to that of the outer air inlet. A short shaft that rotatably passes through the bottom of the outer tube is fixedly disposed at the middle of the bottom of the hollow shielding column. A worm gear is fixedly disposed at the bottom of the short shaft, and the front of the worm gear meshes with the worm sleeve. A retaining ring located at the upper part of the hollow shielding column is fixedly disposed between the upper sidewalls of the inner cavity of the outer tube.

5. An inflatable ring main unit according to claim 2, characterized in that: The air intake self-adjusting component includes a cylinder, the top of which is fixedly connected to the top of the inner cavity of the receiving box. The inside of the cylinder is connected to the inside of the air box. A piston block is slidably disposed between the inner cavity sidewalls of the cylinder, and a vertical rod is fixedly disposed in the middle of the bottom of the piston block.

6. An inflatable ring main unit according to claim 5, characterized in that: The bottom of the vertical rod slides through the bottom of the cylinder and is fixedly mounted with a rack through the base plate. The rack meshes with a gear and slides between the interiors of the two limiting plates. Several springs are evenly fixedly mounted around the bottom outer edge of the piston block, and the bottom of the springs is fixedly connected to the bottom of the inner cavity of the cylinder.

7. An inflatable ring main unit according to claim 3, characterized in that: The self-adjusting direction mechanism includes a support rod, which is fixedly connected between the upper left and right side walls of the inner cavity of the junction box. Several adjusting vertical plates are uniformly rotated and sleeved on the outside of the support rod from left to right. A square push rod located directly below the adjusting vertical plates slides through between the left and right side walls of the junction box.

8. An inflatable ring main unit according to claim 7, characterized in that: The top of the square push rod and the left and right sides of each adjusting vertical plate are fixedly provided with support rods. A square frame is fixedly provided in the middle of the bottom of the square push rod. A reducer is provided directly below the square frame. The front and rear walls of the reducer are fixedly connected to the inner wall of the junction box by connecting rods.

9. An inflatable ring main unit according to claim 8, characterized in that: The input end of the reducer is fixedly connected to a vertical shaft. The bottom of the vertical shaft rotates through the bottom of the support plate and is fixedly equipped with a fan. The fan is located in the upper part of the inner cavity of the outer sleeve. The output end of the reducer is fixedly equipped with a drive wheel. The left and right ends of the drive wheel are in contact with the left and right side walls of the inner cavity of the square frame, respectively.

10. A method for inflating an inflatable ring main unit, characterized in that: For an inflatable ring main unit as described in any one of claims 1-9, the method includes the following steps: Step 1: Open the protective door to expose the air inlet mechanism. Connect the external gas tank to the air inlet mechanism so that the sulfur hexafluoride gas stored in the external gas tank is introduced into the gas box through the air inlet mechanism and the manifold box. As the gas pressure in the gas box changes, the air inlet mechanism adaptively adjusts the gas intake flow rate. Step 2: In the initial low-pressure stage of inflation, sulfur hexafluoride gas enters at a low flow rate through a small throttling area, avoiding eddy current disturbances caused by high-speed airflow under high vacuum. In the middle stage of inflation, as the internal pressure of the gas box increases, the inlet mechanism automatically increases the flow area, increasing the inflation speed without causing impact and shortening the inflation operation time. When approaching the rated pressure, the inlet mechanism automatically reduces the flow area to achieve stable pressure and slow inflation, avoiding pressure overshoot that could cause instantaneous stress impact on the gas box sealing structure. Step 3: The sulfur hexafluoride gas introduced through the inlet mechanism first enters the manifold box. The directional self-adjusting mechanism is driven to work as the sulfur hexafluoride gas flows, thereby dynamically and continuously changing the gas flow direction of the sulfur hexafluoride gas in the manifold box to the gas tank. When the pressure sensor detects that the pressure in the gas tank has reached the rated value, the external gas tank valve is closed, the connection between the inlet mechanism and the external gas tank is disconnected, the protective door is closed, and the inflation operation is completed.

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