A transformer inrush closing protection device

Abstract

The application discloses a transformer inrush closing protection device and belongs to the inrush suppression field. The transformer inrush closing protection device comprises a transformer on a main line, a circuit breaking unit and an inrush suppression cabinet for controlling the circuit breaking unit are arranged on the main line, a phase control device is arranged in the inrush suppression cabinet, the phase control device is composed of a monitoring unit, an analysis unit, a phase wave model library and a controller, the monitoring unit is used for monitoring a residual magnetism closing phase angle, the analysis unit receives phase angle data transmitted by the monitoring unit and compares the phase angle data with phase angles in the phase wave model library, and the controller receives data transmitted by the analysis unit and controls the circuit breaking unit to quickly close when the suitable phase angle is reached so as to suppress the inrush. The phase control device is arranged to capture the phase on the line, the phase control device controls the circuit breaking unit to quickly close when the suitable phase angle is reached, and thus the generation of the inrush can be reduced.

Description

Technical Field

[0001] This invention relates to the field of inrush current suppression technology, specifically to a transformer inrush current closing protection device. Background Technology

[0002] In power systems, the phase angle of the closing voltage of parallel capacitor banks, unloaded transformers, and parallel reactors is usually random and uncertain at the moment of closing operation, which leads to inrush current when these devices are put into operation. The surge impact current generated during closing can reach 10 to 20 times the rated current. During opening, there is also the risk of reignition of the arc gap between the switch contacts and the through voltage of the re-impact. If there is a lack of effective protection measures, the above phenomena will directly affect the performance and lifespan of the switches and capacitor banks in the reactive power compensation equipment.

[0003] Random phase angle closing is the main factor causing inrush current in transformers. If the closing is done under unfavorable conditions, the maximum magnetic flux density in the core can reach twice or more of the normal value, and the core saturation will be very serious, reducing its permeability. Since permeability is proportional to reactance, the excitation reactance will also be greatly reduced, and the excitation current will increase significantly. The inrush current can reach 6 to 8 times the rated current of the transformer, and in severe cases, it can reach more than 10 times. It also contains a large number of high-order harmonics, with decay time ranging from a few seconds to tens of seconds, accompanied by obvious low-frequency vibration and sound.

[0004] Inrush current electrodynamics and "negative" energy severely damage insulation, damage equipment, seriously deteriorate power quality, cause harmonic pollution and voltage dips, and may even cause DC commutation failure. It may also cause frequent failures to put transformers into operation. It is evident that inrush current poses a serious threat to enterprise production, equipment safety, and power grid operation. Therefore, it is necessary to suppress the inrush current generated during closing. Summary of the Invention

[0005] The purpose of this invention is to provide a transformer inrush current closing protection device, which has the advantage of suppressing inrush current and solves the problem of inrush current damaging the power system during closing.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a transformer inrush current closing protection device, comprising a transformer on a main line, wherein a circuit breaker unit and an inrush current suppression cabinet for controlling the circuit breaker unit are provided on the main line, and a phase control device is provided inside the inrush current suppression cabinet.

[0007] Preferably, the phase control device consists of a monitoring unit, an analysis unit, a phase wave model library, and a controller. The monitoring unit is used to monitor the residual magnetism closing phase angle. The analysis unit receives the phase angle data transmitted by the monitoring unit and compares the phase angle data with the phase angle in the phase wave model library. The controller receives the data transmitted by the analysis unit and controls the circuit breaker unit to close quickly when a suitable phase angle is reached to suppress inrush current.

[0008] Preferably, the phase control device is fixedly connected inside the inrush current suppression cabinet. A closing protection box is fixedly connected to the bottom of the inrush current suppression cabinet. An upper connecting plate is fixedly connected to the upper part of the closing protection box. A lower connecting plate is vertically slidably connected to the lower part of the closing protection box. The lower connecting plate is electrically connected to the main line. A conductive sheet is fixedly connected to the lower part of the upper connecting plate. A conductive groove that mates with the conductive sheet is opened on the upper part of the lower connecting plate. A wire is electrically connected to the lower part of the phase control device. The wire is electrically connected to the conductive sheet.

[0009] Preferably, the upper surface of the closing protection box is provided with a connection hole for cooperating with the wire, and an annular airbag is fixedly connected in the connection hole, the annular airbag being in contact with the wire.

[0010] Preferably, a first piston cylinder is fixedly connected to the side wall of the surge suppression cabinet. An air inlet pipe and an air outlet pipe are fixedly connected to the top of the first piston cylinder. A first one-way valve is provided on both the air inlet pipe and the air outlet pipe. The air outlet pipe is connected to an annular airbag. A pressure valve is provided at the end of the air outlet pipe away from the first piston cylinder. A first piston rod is slidably connected inside the first piston cylinder. A first spring is fixedly connected between the first piston rod and the first piston cylinder. A threaded ring is fixedly connected to the side wall of the surge suppression cabinet. A threaded rod is threadedly connected inside the threaded ring. A push rod is fixedly connected to the bottom of the first piston rod. The bottom of the push rod has a rounded corner, and the rounded corner at the bottom of the push rod contacts the side wall of the threaded rod.

[0011] Preferably, the side wall of the lower connecting plate is fitted to the inner wall of the closing protection box, a vent is provided on the bottom wall of the closing protection box, a second piston cylinder is fixedly connected to the bottom wall of the closing protection box, a second piston rod is slidably connected inside the second piston cylinder, the top of the second piston rod is fixedly connected to the lower surface of the lower connecting plate, a third piston cylinder is fixedly connected to the side wall of the closing protection box, a piston plate is slidably connected inside the third piston cylinder, one end of the threaded rod is rotatably connected to the piston plate, the other end of the threaded rod is fixedly connected to a handle, a pipe is fixedly connected between the third piston cylinder and the second piston cylinder, a positioning rod is slidably connected to the inner side wall of the closing protection box, one end of the positioning rod has a rounded corner, the other end of the positioning rod is fixedly connected to a second spring, the rounded end of the positioning rod is inserted into the side wall of the lower connecting plate, and the positioning rod is fixedly connected to the closing protection box through the second spring.

[0012] Preferably, a tank for holding transformer oil is fixedly connected to the side wall of the inrush current suppression cabinet. A sliding plate is slidably connected inside the tank. A cylindrical rod is fixedly connected to the side of the sliding plate. A rack is slidably connected to the upper limit of the cylindrical rod. A third spring is sleeved on the cylindrical rod. The two ends of the third spring are fixedly connected to the sliding plate and the rack, respectively. A cabinet door is rotatably connected to the inrush current suppression cabinet. A gear that meshes with the rack is coaxially fixedly connected to the rotation shaft of the cabinet door.

[0013] Preferably, an oil outlet pipe and an oil return pipe are fixedly connected to the housing, and a second one-way valve is provided on both the oil outlet pipe and the oil return pipe. Both the oil outlet pipe and the oil return pipe are connected to the closing protection box.

[0014] Preferably, a filter box is fixedly connected to the inner wall of the housing, and the end of the oil return pipe away from the closing protection box is located inside the filter box, and a filter screen is fixedly connected to the end of the filter box.

[0015] Preferably, a scraper is fixedly connected to the slide plate on the opposite side of the cylindrical rod. A through groove is provided on the filter box to cooperate with the scraper. The scraper is slidably connected to the filter screen. Multiple rectangular grooves are provided on the scraper. A rectangular cylinder is fixedly connected to the side wall of the filter box. Two rectangular rods are fixedly connected to the end of the scraper. The rectangular rods are slidably connected inside the rectangular cylinder. A slag storage box is fixedly connected to the outer wall of the box body. The rectangular cylinder is connected to the slag storage box. A box door is installed on the top of the slag storage box.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0017] 1. This invention uses a phase control device to capture the phase on the line. When a suitable phase angle is reached, the phase control device controls the circuit breaker unit to close quickly, thereby reducing the generation of inrush current.

[0018] 2. The present invention can seal the closing protection box by setting an annular airbag to prevent the transformer oil inside the closing protection box from leaking.

[0019] 3. The present invention reduces the electric arc generated when the inrush suppression cabinet is switched on by setting up a second piston cylinder, a third piston cylinder and a positioning rod.

[0020] 4. By setting up a box and other structures, the present invention enables transformer oil to flow into the closing protection box, thereby eliminating the electric arc generated when the inrush current suppression cabinet is switched on and off. Attached Figure Description

[0021] Figure 1 This is a simplified structural diagram of the connection circuit of the inrush suppression cabinet of the present invention;

[0022] Figure 2This is a flowchart illustrating the process of suppressing inrush flow using the phase control device of the present invention.

[0023] Figure 3 This is a schematic diagram of the overall structure of the surge suppression cabinet of the present invention. Figure 1 ;

[0024] Figure 4 This is a schematic diagram of the overall structure of the surge suppression cabinet of the present invention. Figure 2 ;

[0025] Figure 5 This is a schematic diagram of the structure of the closing protection box of the present invention;

[0026] Figure 6 This is a schematic diagram of the structure of the connecting plate in this invention;

[0027] Figure 7 This is a schematic diagram of the structure of the first piston cylinder of the present invention;

[0028] Figure 8 This is a schematic diagram of the structure of the lower connecting plate of the present invention;

[0029] Figure 9 This is a schematic diagram of the rack structure of the present invention;

[0030] Figure 10 This is a schematic diagram of the structure of the filter box in this invention.

[0031] In the diagram: 1. Inrush suppression cabinet; 11. Cabinet door; 12. Phase control device; 121. Wire; 13. Gear; 2. Closing protection box; 201. Vent hole; 21. Upper connecting plate; 22. Conductive sheet; 23. Annular airbag; 24. Air outlet pipe; 25. First one-way valve; 26. Pressure valve; 27. Positioning rod; 28. Second spring; 29. ​​Connecting hole; 3. Lower connecting plate; 31. Conductive groove; 32. Second piston cylinder; 33. Second piston rod; 34. Pipe; 35. Third piston cylinder; 36. 37. Piston plate; 38. Threaded rod; 39. Threaded ring; 4. Handle; 40. First piston cylinder; 41. First piston rod; 42. First spring; 43. Push rod; 44. Inlet pipe; 5. Housing; 51. Return oil pipe; 52. Outlet oil pipe; 53. Second check valve; 54. Slide plate; 55. Cylindrical rod; 56. Rack; 57. Third spring; 58. Scraper; 58. Rectangular rod; 59. Rectangular groove; 60. Filter box; 61. Filter screen; 62. Rectangular cylinder; 63. Slag storage box; 64. Box door. Detailed Implementation

[0032] 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.

[0033] Example 1

[0034] Reference Figure 1 and Figure 2 The present invention provides a technical solution: a transformer inrush current closing protection device, including a transformer on the main line, a circuit breaker unit on the main line and an inrush current suppression cabinet 1 for controlling the circuit breaker unit, and a phase control device 12 inside the inrush current suppression cabinet 1.

[0035] The phase control device 12 inside the inrush current suppression cabinet 1 uses phase control technology to capture the phase on the line. When a suitable phase angle is reached, the phase control device 12 controls the circuit breaker unit to close quickly, thereby reducing the generation of inrush current.

[0036] Reference Figure 1 and Figure 2 The phase control device 12 consists of a monitoring unit, an analysis unit, a phase wave model library, and a controller. The monitoring unit is used to monitor the residual magnetism closing phase angle. The analysis unit receives the phase angle data transmitted by the monitoring unit and compares the phase angle data with the phase angle in the phase wave model library. The controller receives the data transmitted by the analysis unit and controls the circuit breaker unit to close quickly when a suitable phase angle is reached to suppress inrush current.

[0037] The controller calculates the received residual magnetism closing phase angle and performs circuit breaker dispersion prevention for the circuit breaker unit. The monitoring unit monitors the voltage of the main line in real time through the voltage transformer. The analysis unit receives the data transmitted by the monitoring unit and compares it with the data in the phase wave model library. The controller promptly judges and executes the received information. The circuit breaker unit uses a fast switch for phase-controlled closing and closes the circuit at a suitable phase angle, at which time the inrush current value is minimized, thereby achieving the effect of suppressing inrush current.

[0038] Example 2

[0039] Reference Figures 3-8Furthermore, based on Embodiment 1, the phase control device 12 is fixedly connected inside the inrush current suppression cabinet 1. The bottom of the inrush current suppression cabinet 1 is fixedly connected to the closing protection box 2. The upper part of the closing protection box 2 is fixedly connected to the upper part. The lower part of the closing protection box 2 is vertically slidably connected to the lower part. The lower connecting plate 3 is electrically connected to the main line. The lower part of the upper connecting plate 21 is fixedly connected to the conductive sheet 22. The upper part of the lower connecting plate 3 is provided with a conductive groove 31 that cooperates with the conductive sheet 22. The lower part of the phase control device 12 is electrically connected to the wire 121. The wire 121 is electrically connected to the conductive sheet 22.

[0040] The phase control device 12 is installed in the inrush current suppression cabinet 1 and is protected by the inrush current suppression cabinet 1. The phase control device 12 is connected to the circuit. The closing protection box 2 protects the upper connecting plate 21 and the lower connecting plate 3, so that when the conductive piece 22 of the upper connecting plate 21 is inserted or removed from the conductive groove 31 on the lower connecting plate 3, the arc is blocked by the closing protection box 2. When the conductive piece 22 is inserted into the conductive groove 31, the inrush current suppression cabinet 1 is connected to the line.

[0041] Reference Figures 3-8 The upper surface of the closing protection box 2 is provided with a connection hole 29 that mates with the wire 121. An annular airbag 23 is fixedly connected inside the connection hole 29 and fits against the wire 121.

[0042] By opening a connection hole 29 on the top of the closing protection box 2, the wire 121 between the phase control device 12 and the conductive sheet 22 can be inserted. The annular airbag 23 inside the connection hole 29 can seal the closing protection box 2 to prevent the transformer oil inside the closing protection box 2 from leaking.

[0043] Reference Figures 3-8 A first piston cylinder 4 is fixedly connected to the side wall of the surge suppression cabinet 1. An air inlet pipe 44 and an air outlet pipe 24 are fixedly connected to the top of the first piston cylinder 4. A first one-way valve 25 is provided on both the air inlet pipe 44 and the air outlet pipe 24. The air outlet pipe 24 is connected to the annular airbag 23. A pressure valve 26 is provided at the end of the air outlet pipe 24 away from the first piston cylinder 4. A first piston rod 41 is slidably connected inside the first piston cylinder 4. A first spring 42 is fixedly connected between the first piston rod 41 and the first piston cylinder 4. A threaded ring 38 is fixedly connected to the side wall of the surge suppression cabinet 1. A threaded rod 37 is threadedly connected inside the threaded ring 38. A push rod 43 is fixedly connected to the bottom of the first piston rod 41. The bottom of the push rod 43 is rounded, and the rounded part of the bottom of the push rod 43 contacts the side wall of the threaded rod 37.

[0044] Rotating the threaded rod 37 allows for axial movement between the threaded rod 37 and the threaded ring 38. The bottom of the push rod 43 contacts the side wall of the threaded rod 37, thus pushing the push rod 43 upwards during axial movement. This upward movement causes the push rod 43 to move the first piston rod 41, which is fixedly connected to its top, upwards. A first spring 42 is provided between the first piston rod 41 and the first piston cylinder 4, allowing the first piston rod 41 to slide reciprocally within the first piston cylinder 4. Since the first piston cylinder 4 is fitted with an inlet pipe 44 and an outlet pipe 2... Each of the four sections is equipped with a first one-way valve 25, allowing external air to be drawn in through the air inlet pipe 44. The drawn air is then discharged into the annular airbag 23 through the air outlet pipe 24. If the annular airbag 23 is deficient in air, it will expand and fit against the wire 121, maintaining the sealing of the closing protection box 2. If there is too much air in the annular airbag 23 or the annular airbag 23 is not deficient in air, the pressure inside the annular airbag 23 will increase, allowing the excess air to be discharged through the pressure valve 26, thus preventing the annular airbag 23 from over-expanding and being damaged.

[0045] Example 3

[0046] Reference Figure 4 , Figure 5 , Figure 7 and Figure 8 Furthermore, based on Embodiment 2, the side wall of the lower connecting plate 3 is fitted to the inner wall of the closing protection box 2. A vent hole 201 is provided on the bottom wall of the closing protection box 2. A second piston cylinder 32 is fixedly connected to the bottom wall of the closing protection box 2. A second piston rod 33 is slidably connected inside the second piston cylinder 32. The top of the second piston rod 33 is fixedly connected to the lower surface of the lower connecting plate 3. A third piston cylinder 35 is fixedly connected to the side wall of the closing protection box 2. A piston plate 36 is slidably connected inside the third piston cylinder 35. One end of the threaded rod 37 is rotatably connected to the piston plate 36, and the other end of the threaded rod 37 is fixedly connected to the handle 39. A pipe 34 is fixedly connected between the third piston cylinder 35 and the second piston cylinder 32. A positioning rod 27 is slidably connected to the inner side wall of the closing protection box 2. One end of the positioning rod 27 is provided with a rounded corner, and the other end of the positioning rod 27 is fixedly connected to the second spring 28. The rounded end of the positioning rod 27 is inserted into the side wall of the lower connecting plate 3. The positioning rod 27 is fixedly connected to the closing protection box 2 through the second spring 28.

[0047] The rotation of the threaded rod 37 can be easily controlled by setting the handle 39. Manually rotating the handle 39 causes the threaded rod 37 to rotate, at which point the threaded rod 37 can move axially relative to the threaded ring 38. Since the third piston cylinder 35 is relatively fixed to the threaded ring 38, the threaded rod 37 can move outward from the third piston cylinder 35. At this time, the threaded rod 37 drives the piston plate 36 to slide outward from the third piston cylinder 35, and the third piston cylinder 35 can extract air from the second piston cylinder 32 through the pipe 34. Since the positioning rod 27 is inserted into the side wall of the lower connecting plate 3, the second spring 28 applies a pushing force to the positioning rod 27, causing the lower connecting plate 3 to be blocked. As a result, the lower connecting plate 3 is resisted and will not easily move downward. Therefore, the second piston rod 33 does not initially move into the second piston cylinder 32. As the second piston cylinder 32 slides, the third piston cylinder 35 continuously draws air from the second piston cylinder 32, causing the negative pressure inside the second piston cylinder 32 to increase. Eventually, the negative pressure inside the second piston cylinder 32 causes the second piston rod 33 to slide into the second piston cylinder 32. At this point, the suction force of the negative pressure overcomes the force exerted by the second spring 28 on the positioning rod 27, causing the positioning rod 27 to be inserted into the lower connecting plate 3. Consequently, the lower connecting plate 3 moves downward rapidly, causing the conductive sheet 22 to separate from the conductive groove 31. Because the separation speed between the conductive sheet 22 and the conductive groove 31 is fast, the generation of electric arc can be reduced. After the lower connecting plate 3 moves downward, the positioning rod 27 at the bottom is inserted into the side wall of the lower connecting plate 3. The end of the positioning rod 27 inserted into the lower connecting plate 3 has a rounded corner, which makes it easy for the positioning rod 27 to detach from the lower connecting plate 3.

[0048] When the circuit is closed, the reverse rotation of the threaded rod 37 causes the piston plate 36 to slide into the interior of the third piston cylinder 35. At this time, the air in the third piston cylinder 35 tends to enter the second piston cylinder 32 through the pipe 34. At this time, the lower positioning rod 27 blocks the lower connecting plate 3, making it difficult for the second piston rod 33 to slide upward. As the positive pressure in the third piston cylinder 35 increases, its pressure eventually overcomes the force of the lower positioning rod 27 inserted into the lower connecting plate 3, thereby causing the lower positioning rod 27 to disengage from the lower connecting plate 3. At the instant the lower positioning rod 27 disengages from the lower connecting plate 3, the positive pressure is released, and the second piston rod 33 quickly drives the lower connecting plate 3 to move upward, so that the conductive piece 22 is quickly inserted into the conductive groove 31, thereby reducing the generation of electric arc. After the lower connecting plate 3 moves upward, the upper positioning rod 27 is inserted into the lower connecting plate 3, positioning the lower connecting plate 3, so that the conductive piece 22 can be stably inserted into the conductive groove 31.

[0049] Example 4

[0050] Reference Figure 3 , Figure 9 and Figure 10Furthermore, based on Embodiment 3, a box 5 for holding transformer oil is fixedly connected to the side wall of the inrush current suppression cabinet 1. A sliding plate 54 is slidably connected inside the box 5. A cylindrical rod 55 is fixedly connected to the side of the sliding plate 54. A rack 56 is slidably connected to the upper limit of the cylindrical rod 55. A third spring 57 is sleeved on the cylindrical rod 55. The two ends of the third spring 57 are fixedly connected to the sliding plate 54 and the rack 56 respectively. A cabinet door 11 is rotatably connected to the inrush current suppression cabinet 1. A gear 13 that meshes with the rack 56 is coaxially fixedly connected to the rotation shaft of the cabinet door 11.

[0051] As the cabinet door 11 is opened, the gear 13 rotates, causing the rack 56 to slide towards the slide plate 54. Since the side wall of the lower connecting plate 3 is in contact with the inner wall of the closing protection box 2, the transformer oil in the box 5 will not flow into the closing protection box 2. Therefore, the position of the slide plate 54 remains unchanged. The sliding rack 56 compresses the third spring 57, which then positions the opened cabinet door 11. The third spring 57 then exerts a pushing force on the slide plate 54. When the lower connecting plate 3 slides down, the transformer oil in the box 5 can flow into the closing protection box 2. Under the pushing force of the third spring 57, the slide plate 54 slides into the box 5, allowing the transformer oil in the box 5 to flow into the closing protection box 2. The flow of transformer oil assists in pushing the lower part of the lower connecting plate 3, further accelerating the downward speed of the lower connecting plate 3. When the transformer oil flows into the closing protection box 2, it can also eliminate the electric arc.

[0052] Reference Figure 3 , Figure 9 and Figure 10 The housing 5 is fixedly connected to an oil outlet pipe 52 and an oil return pipe 51. Both the oil outlet pipe 52 and the oil return pipe 51 are equipped with a second check valve 53, and both the oil outlet pipe 52 and the oil return pipe 51 are connected to the closing protection box 2.

[0053] Since the oil outlet pipe 52 and the oil return pipe 51 on the housing 5 are both equipped with second one-way valves 53, the transformer oil can enter the closing protection box 2 through the oil outlet pipe 52, and the transformer oil in the closing protection box 2 can flow back to the housing 5 through the oil return pipe 51. Specifically, when the cabinet door 11 is closed, the gear 13 drives the rack 56 to slide away from the slide plate 54. At this time, the third spring 57 is stretched and repositions the cabinet door 11. At this time, the third spring 57 has a pulling force on the slide plate 54. When the lower connecting plate 3 moves up, the transformer oil in the closing protection box 2 can flow back to the housing 5 through the oil return pipe 51. At this time, in conjunction with the pulling force of the third spring 57 on the slide plate 54, the transformer oil quickly flows back to the housing 5, thereby assisting the upward movement of the lower connecting plate 3, so that the lower connecting plate 3 moves up quickly, thereby improving the arc elimination effect.

[0054] Reference Figure 3 , Figure 9 and Figure 10 A filter box 6 is fixedly connected to the inner wall of the housing 5. The end of the return oil pipe 51 away from the closing protection box 2 is located inside the filter box 6. A filter screen 61 is fixedly connected to the end of the filter box 6.

[0055] The transformer oil flowing back to the housing 5 through the return oil pipe 51 first passes through the filter box 6. Since the filter box 6 is equipped with a filter screen 61, the transformer oil flowing back to the housing 5 can be filtered, so that any remaining impurities in the transformer oil are removed. This prevents impurities from remaining in the transformer oil and causing a strong electric arc when the conductive sheet 22 is inserted into the conductive groove 31.

[0056] Reference Figure 3 , Figure 9 and Figure 10 A scraper 58 is fixedly connected to the slide plate 54 on the opposite side of the cylindrical rod 55. A through groove is opened on the filter box 6 to cooperate with the scraper 58. The scraper 58 is slidably connected to the filter screen 61. Multiple rectangular grooves 59 are opened on the scraper 58. A rectangular cylinder 62 is fixedly connected to the side wall of the filter box 6. Two rectangular rods 581 are fixedly connected to the end of the scraper 58. The rectangular rods 581 are slidably connected inside the rectangular cylinder 62. A slag storage box 63 is fixedly connected to the outer wall of the box body 5. The rectangular cylinder 62 is connected to the slag storage box 63. A box door 64 is installed on the top of the slag storage box 63.

[0057] As the slide plate 54 slides into the housing 5, the transformer oil inside the housing 5 is discharged into the closing protection box 2 through the oil outlet pipe 52. At this time, the scraper 58 fixedly connected to the slide plate 54 moves and scrapes the filter screen 61. The scraped impurities are pushed into the rectangular cylinder 62 by the scraper 58, thus preventing a large amount of impurities from remaining in the filter box 6, ensuring the permeability of the filter screen 61, and allowing the transformer oil to flow back into the housing 5 quickly. The pushed impurities can finally pass through the rectangular cylinder 62 into the housing 5. The slag is placed into the slag storage box 63. The box door 64 is opened periodically to clean the slag storage box 63. During the process of the transformer oil flowing back into the box 5, the rectangular groove 59 on the scraper 58 will not obstruct the flow of the transformer oil, ensuring the rapid flow of the transformer oil so that the conductive plate 22 can be quickly inserted into the conductive groove 31. The rectangular rod 581 has the same thickness as the scraper 58, so the rectangular rod 581 can position the scraper 58, so that the scraper 58 can slide smoothly into the rectangular cylinder 62.

[0058] Working principle: This transformer inrush current closing protection device uses phase control technology in the phase control device 12 inside the inrush current suppression cabinet 1 to capture the phase on the line. When a suitable phase angle is reached, the phase control device 12 controls the circuit breaker unit to close quickly, thereby reducing the generation of inrush current. The controller calculates the received residual magnetism closing phase angle and performs circuit breaker dispersion prevention for the circuit breaker unit. The monitoring unit monitors the voltage of the main line in real time through the voltage transformer. The analysis unit receives the data transmitted by the monitoring unit and compares it with the data in the phase wave model library. The controller promptly judges and executes the received information. The circuit breaker unit uses a fast switch to perform phase control closing, closing in time at a suitable phase angle, at which time the inrush current value is minimized, thereby achieving the effect of suppressing inrush current.

[0059] The phase control device 12 is installed in the inrush current suppression cabinet 1 and protected by the inrush current suppression cabinet 1. The phase control device 12 is connected to the circuit. The closing protection box 2 protects the upper connecting plate 21 and the lower connecting plate 3, so that when the conductive piece 22 of the upper connecting plate 21 is inserted into the conductive groove 31 on the lower connecting plate 3, the arc is blocked by the closing protection box 2. When the conductive piece 22 is inserted into the conductive groove 31, the inrush current suppression cabinet 1 is connected to the line. By opening a connection hole 29 on the top of the closing protection box 2, the wire 121 between the phase control device 12 and the conductive piece 22 can be inserted. The annular airbag 23 in the connection hole 29 can seal the closing protection box 2 to prevent the transformer oil in the closing protection box 2 from leaking.

[0060] Rotating the threaded rod 37 allows for axial movement between the threaded rod 37 and the threaded ring 38. The bottom of the push rod 43 contacts the side wall of the threaded rod 37, thus pushing the push rod 43 upwards during axial movement. This upward movement causes the push rod 43 to move the first piston rod 41, which is fixedly connected to its top, upwards. A first spring 42 is provided between the first piston rod 41 and the first piston cylinder 4, allowing the first piston rod 41 to slide reciprocally within the first piston cylinder 4. Since the first piston cylinder 4 is fitted with an inlet pipe 44 and an outlet pipe 2... Each of the four sections is equipped with a first one-way valve 25, allowing external air to be drawn in through the air inlet pipe 44. The drawn air is then discharged into the annular airbag 23 through the air outlet pipe 24. If the annular airbag 23 is deficient in air, it will expand and fit against the wire 121, maintaining the sealing of the closing protection box 2. If there is too much air in the annular airbag 23 or the annular airbag 23 is not deficient in air, the pressure inside the annular airbag 23 will increase, allowing the excess air to be discharged through the pressure valve 26, thus preventing the annular airbag 23 from over-expanding and being damaged.

[0061] The rotation of the threaded rod 37 can be easily controlled by setting the handle 39. Manually rotating the handle 39 causes the threaded rod 37 to rotate, at which point the threaded rod 37 can move axially relative to the threaded ring 38. Since the third piston cylinder 35 is relatively fixed to the threaded ring 38, the threaded rod 37 can move outward from the third piston cylinder 35. At this time, the threaded rod 37 drives the piston plate 36 to slide outward from the third piston cylinder 35, and the third piston cylinder 35 can extract air from the second piston cylinder 32 through the pipe 34. Since the positioning rod 27 is inserted into the side wall of the lower connecting plate 3, the second spring 28 applies a pushing force to the positioning rod 27, causing the lower connecting plate 3 to be blocked. As a result, the lower connecting plate 3 is resisted and will not easily move downward. Therefore, the second piston rod 33 does not initially move into the second piston cylinder 32. As the second piston cylinder 32 slides, the third piston cylinder 35 continuously draws air from the second piston cylinder 32, causing the negative pressure inside the second piston cylinder 32 to increase. Eventually, the negative pressure inside the second piston cylinder 32 causes the second piston rod 33 to slide into the second piston cylinder 32. At this point, the suction force of the negative pressure overcomes the force exerted by the second spring 28 on the positioning rod 27, causing the positioning rod 27 to be inserted into the lower connecting plate 3. Consequently, the lower connecting plate 3 moves downward rapidly, causing the conductive sheet 22 to separate from the conductive groove 31. Because the separation speed between the conductive sheet 22 and the conductive groove 31 is fast, the generation of electric arc can be reduced. After the lower connecting plate 3 moves downward, the positioning rod 27 at the bottom is inserted into the side wall of the lower connecting plate 3. The end of the positioning rod 27 inserted into the lower connecting plate 3 has a rounded corner, which makes it easy for the positioning rod 27 to detach from the lower connecting plate 3.

[0062] When the circuit is closed, the reverse rotation of the threaded rod 37 causes the piston plate 36 to slide into the interior of the third piston cylinder 35. At this time, the air in the third piston cylinder 35 tends to enter the second piston cylinder 32 through the pipe 34. At this time, the lower positioning rod 27 blocks the lower connecting plate 3, making it difficult for the second piston rod 33 to slide upward. As the positive pressure in the third piston cylinder 35 increases, its pressure eventually overcomes the force of the lower positioning rod 27 inserted into the lower connecting plate 3, thereby causing the lower positioning rod 27 to disengage from the lower connecting plate 3. At the instant the lower positioning rod 27 disengages from the lower connecting plate 3, the positive pressure is released, and the second piston rod 33 quickly drives the lower connecting plate 3 to move upward, so that the conductive piece 22 is quickly inserted into the conductive groove 31, thereby reducing the generation of electric arc. After the lower connecting plate 3 moves upward, the upper positioning rod 27 is inserted into the lower connecting plate 3, positioning the lower connecting plate 3, so that the conductive piece 22 can be stably inserted into the conductive groove 31.

[0063] As the cabinet door 11 is opened, the gear 13 rotates, causing the rack 56 to slide towards the slide plate 54. Since the side wall of the lower connecting plate 3 is in contact with the inner wall of the closing protection box 2, the transformer oil in the box 5 will not flow into the closing protection box 2. Therefore, the position of the slide plate 54 remains unchanged. The sliding rack 56 compresses the third spring 57, which then positions the opened cabinet door 11. The third spring 57 then exerts a pushing force on the slide plate 54. When the lower connecting plate 3 slides down, the transformer oil in the box 5 can flow into the closing protection box 2. Under the pushing force of the third spring 57, the slide plate 54 slides into the box 5, allowing the transformer oil in the box 5 to flow into the closing protection box 2. The flow of transformer oil assists in pushing the lower part of the lower connecting plate 3, further accelerating the downward speed of the lower connecting plate 3. When the transformer oil flows into the closing protection box 2, it can also eliminate the electric arc.

[0064] Since the oil outlet pipe 52 and the oil return pipe 51 on the housing 5 are both equipped with second one-way valves 53, the transformer oil can enter the closing protection box 2 through the oil outlet pipe 52, and the transformer oil in the closing protection box 2 can flow back to the housing 5 through the oil return pipe 51. Specifically, when the cabinet door 11 is closed, the gear 13 drives the rack 56 to slide away from the slide plate 54. At this time, the third spring 57 is stretched and the cabinet door 11 is repositioned. At this time, the third spring 57 has a pulling force on the slide plate 54. When the lower connecting plate 3 moves up, the transformer oil in the closing protection box 2 can flow back to the housing 5 through the oil return pipe 51. At this time, in conjunction with the pulling force of the third spring 57 on the slide plate 54, the transformer oil quickly flows back to the housing 5, thereby assisting the upward movement of the lower connecting plate 3, so that the lower connecting plate 3 moves up quickly, thereby improving the arc elimination effect.

[0065] The transformer oil flowing back to the housing 5 through the return oil pipe 51 first passes through the filter box 6. Since the filter box 6 is equipped with a filter screen 61, the transformer oil flowing back to the housing 5 can be filtered, so that any remaining impurities in the transformer oil are removed. This prevents impurities from remaining in the transformer oil and causing a strong electric arc when the conductive sheet 22 is inserted into the conductive groove 31.

[0066] As the slide plate 54 slides into the housing 5, the transformer oil inside the housing 5 is discharged into the closing protection box 2 through the oil outlet pipe 52. At this time, the scraper 58 fixedly connected to the slide plate 54 moves and scrapes the filter screen 61. The scraped impurities are pushed into the rectangular cylinder 62 by the scraper 58, thus preventing a large amount of impurities from remaining in the filter box 6, ensuring the permeability of the filter screen 61, and allowing the transformer oil to flow back into the housing 5 quickly. The pushed impurities can finally pass through the rectangular cylinder 62 into the housing 5. The slag is placed into the slag storage box 63. The box door 64 is opened periodically to clean the slag storage box 63. During the process of the transformer oil flowing back into the box 5, the rectangular groove 59 on the scraper 58 will not obstruct the flow of the transformer oil, ensuring the rapid flow of the transformer oil so that the conductive plate 22 can be quickly inserted into the conductive groove 31. The rectangular rod 581 has the same thickness as the scraper 58, so the rectangular rod 581 can position the scraper 58, so that the scraper 58 can slide smoothly into the rectangular cylinder 62.

[0067] 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. A transformer inrush current closing protection device, comprising a transformer on a main line, characterized in that: The main line is equipped with a circuit breaker unit and a surge current suppression cabinet (1) for controlling the circuit breaker unit. The surge current suppression cabinet (1) is equipped with a phase control device (12). The phase control device (12) consists of a monitoring unit, an analysis unit, a phase wave model library, and a controller; The monitoring unit is used to monitor the residual magnetism closing phase angle; The analysis unit receives the phase angle data transmitted by the monitoring unit and compares the phase angle data with the phase angle in the phase wave model library; The controller receives data transmitted by the analysis unit and controls the circuit breaker to close quickly when a suitable phase angle is reached in order to suppress inrush current. The phase control device (12) is fixedly connected inside the surge current suppression cabinet (1). The bottom of the surge current suppression cabinet (1) is fixedly connected to the closing protection box (2). The upper part of the closing protection box (2) is fixedly connected to the upper part. The lower part of the closing protection box (2) is vertically slidably connected to the lower part. The lower connecting plate (3) is electrically connected to the main line. The lower part of the upper connecting plate (21) is fixedly connected to the conductive sheet (22). The upper part of the lower connecting plate (3) is provided with a conductive groove (31) that cooperates with the conductive sheet (22). The lower part of the phase control device (12) is electrically connected to the wire (121). The wire (121) is electrically connected to the conductive sheet (22). The upper surface of the closing protection box (2) is provided with a connection hole (29) that cooperates with the wire (121). An annular airbag (23) is fixedly connected in the connection hole (29), and the annular airbag (23) is in contact with the wire (121). A first piston cylinder (4) is fixedly connected to the side wall of the surge suppression cabinet (1). An air inlet pipe (44) and an air outlet pipe (24) are fixedly connected to the top of the first piston cylinder (4). A first one-way valve (25) is provided on both the air inlet pipe (44) and the air outlet pipe (24). The air outlet pipe (24) is connected to an annular airbag (23). A pressure valve (26) is provided at the end of the air outlet pipe (24) away from the first piston cylinder (4). A first one-way valve (25) is slidably connected inside the first piston cylinder (4). A piston rod (41) is fixedly connected to a first spring (42) between the first piston rod (41) and the first piston cylinder (4). A threaded ring (38) is fixedly connected to the side wall of the surge suppression cabinet (1). A threaded rod (37) is internally threaded to the threaded ring (38). A push rod (43) is fixedly connected to the bottom of the first piston rod (41). The bottom of the push rod (43) is provided with a rounded corner, and the rounded corner at the bottom of the push rod (43) contacts the side wall of the threaded rod (37). The side wall of the lower connecting plate (3) is attached to the inner wall of the closing protection box (2). A vent hole (201) is provided on the bottom wall of the closing protection box (2). A second piston cylinder (32) is fixedly connected to the bottom wall of the closing protection box (2). A second piston rod (33) is slidably connected inside the second piston cylinder (32). The top of the second piston rod (33) is fixedly connected to the lower surface of the lower connecting plate (3). A third piston cylinder (35) is fixedly connected to the side wall of the closing protection box (2). A piston plate (36) is slidably connected inside the third piston cylinder (35). One end of the threaded rod (37) is rotatably connected to the piston plate (36). The other end of the threaded rod (37) is fixedly connected to a handle (39). A pipe (34) is fixedly connected between the third piston cylinder (35) and the second piston cylinder (32). A positioning rod (27) is slidably connected to the inner side wall of the closing protection box (2). One end of the positioning rod (27) is rounded, and the other end of the positioning rod (27) is fixedly connected to a second spring (28). The rounded end of the positioning rod (27) is inserted into the side wall of the lower connecting plate (3). The positioning rod (27) is fixedly connected to the closing protection box (2) through the second spring (28).

2. The transformer inrush current closing protection device according to claim 1, characterized in that: A tank (5) for holding transformer oil is fixedly connected to the side wall of the surge suppression cabinet (1). A sliding plate (54) is slidably connected inside the tank (5). A cylindrical rod (55) is fixedly connected to the side of the sliding plate (54). A rack (56) is slidably connected to the upper limit of the cylindrical rod (55). A third spring (57) is sleeved on the cylindrical rod (55). The two ends of the third spring (57) are fixedly connected to the sliding plate (54) and the rack (56) respectively. A cabinet door (11) is rotatably connected to the surge suppression cabinet (1). A gear (13) that meshes with the rack (56) is coaxially fixedly connected to the rotating shaft of the cabinet door (11).

3. A transformer inrush current closing protection device according to claim 2, characterized in that: The housing (5) is fixedly connected to an oil outlet pipe (52) and an oil return pipe (51). Both the oil outlet pipe (52) and the oil return pipe (51) are equipped with a second check valve (53), and both the oil outlet pipe (52) and the oil return pipe (51) are connected to the closing protection box (2).

4. A transformer inrush current closing protection device according to claim 3, characterized in that: A filter box (6) is fixedly connected to the inner wall of the box (5). The end of the return oil pipe (51) away from the closing protection box (2) is located inside the filter box (6). A filter screen (61) is fixedly connected to the end of the filter box (6).

5. A transformer inrush current closing protection device according to claim 4, characterized in that: A scraper (58) is fixedly connected to the slide plate (54) on the opposite side of the cylindrical rod (55). A through groove is provided on the filter box (6) to cooperate with the scraper (58). The scraper (58) is slidably connected to the filter screen (61). Multiple rectangular grooves (59) are provided on the scraper (58). A rectangular cylinder (62) is fixedly connected to the side wall of the filter box (6). Two rectangular rods (581) are fixedly connected to the end of the scraper (58). The rectangular rods (581) are slidably connected inside the rectangular cylinder (62). A slag storage box (63) is fixedly connected to the outer wall of the box body (5). The rectangular cylinder (62) is connected to the slag storage box (63). A box door (64) is installed on the top of the slag storage box (63).

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