Vacuum arc-extinguishing chamber with insulating ceramic ring

Abstract

The utility model provides a vacuum arc-extinguishing chamber with an insulating ceramic ring, which relates to the technical field of vacuum arc-extinguishing chambers and comprises a moving end conducting rod, a static end conducting rod, a moving contact, a static contact, a moving end cover plate, a corrugated pipe, a corrugated pipe shielding cover, a main shielding cover, an insulating ceramic shell, a moving end shielding cover, a static end cover plate and a static end shielding cover. When the vacuum arc-extinguishing chamber is switched on, current between the static contact and the static end metal shielding cover is isolated, electric field distortion generated by the static end cover plate is prevented, electric field optimization is facilitated, meanwhile, the advantages of good heat dissipation, high mechanical strength and the like of the metal cover plate are reserved, and the structure design is reasonable.

Description

Technical Field

[0001] This utility model relates to the field of vacuum interrupter technology, and in particular to a vacuum interrupter with an insulating ceramic ring. Background Technology

[0002] Switchgear is a crucial control and protection device in power systems. Vacuum and SF6 are two high-performance insulation and arc-extinguishing media widely used in circuit breakers. After the Kyoto Protocol officially designated SF6 as a greenhouse gas, research on vacuum circuit breakers became a significant research direction in the high-voltage switchgear field both domestically and internationally. Many experts and scholars have conducted research at various levels on different technical aspects of vacuum interrupters, aiming to develop vacuum circuit breakers towards higher voltage levels and larger capacities. However, the ultimate breaking capacity of the vacuum interrupter, as the core component of a vacuum circuit breaker, directly affects the overall performance of the vacuum circuit breaker.

[0003] Only with good mechanical strength, high insulation level, and breaking capacity can the stable and reliable operation of vacuum switches be guaranteed. Vacuum interrupters are mainly used in indoor and outdoor high and low voltage vacuum switches (mainly referring to vacuum circuit breakers, vacuum contactors, load switches, etc.), and are widely used in power, metallurgy, mining, and railway power transmission and distribution systems for protection and control. The working principle of a vacuum interrupter is that its internal high vacuum state serves as the insulating and arc-extinguishing medium when the chamber is energized. When the moving and stationary contacts are energized and separated under the control of the operating mechanism, a vacuum arc is generated between the contacts, which is extinguished when the current crosses zero, thereby interrupting the current in the circuit and achieving the purpose of overload protection for the power grid. The main structural components of a vacuum interrupter are an insulating shell, moving and stationary end covers, contacts, bellows, shielding cover, moving and stationary conductive rods, guide sleeves, etc. The corresponding components are sealed into a closed vacuum chamber using vacuum brazing technology. Utilizing the excellent insulation and arc-extinguishing properties of vacuum, the arc can be quickly extinguished and the current suppressed after the power supply is cut off. This requires that the interconnected parts of the vacuum interrupter located on the outer shell structure must be able to maintain the vacuum level inside the tube for a long time, and there must be no defects that cause chronic leakage and reduce the vacuum level. As a result, the scrapping of parts and the entire tube, as well as the significant decrease in the yield rate, are very common. Utility Model Content

[0004] To address the shortcomings of existing technologies, this utility model provides a vacuum interrupter with an insulating ceramic ring. When the vacuum interrupter is closed, it isolates the current between the stationary contact and the stationary metal shield, preventing electric field distortion caused by the stationary cover plate, which is beneficial for electric field optimization. At the same time, it retains the advantages of good heat dissipation and high mechanical strength of the metal cover plate. Its structural design is reasonable and its performance is good.

[0005] A vacuum interrupter with an insulating ceramic ring includes a moving end conductive rod, a stationary end conductive rod, a moving contact, a stationary contact, a moving end cover plate, a bellows, a bellows shield, a main shield, an insulating ceramic shell, a moving end shield, a stationary end cover plate, and a stationary end shield.

[0006] The main shield is disposed inside the insulating ceramic shell, and the two are coaxially distributed. One end of the insulating ceramic shell is sealed to the moving end cover plate, and the other end of the insulating ceramic shell is sealed to the stationary end cover plate. The moving end cover plate, the stationary end cover plate, and the insulating ceramic shell constitute a vacuum container. The moving end shield is disposed outside the moving end cover plate. The moving contact and the stationary contact are disposed in the vacuum container and are arranged opposite to each other. The stationary contact is fixedly disposed in the vacuum container and is connected to one end of the stationary end conductive rod. The other end of the stationary end conductive rod passes through the stationary end. A cover plate is formed to create a seal; the moving contact is movably disposed in the vacuum container, and the moving contact is connected to one end of the moving end conductive rod. The other end of the moving end conductive rod passes through the moving end cover plate and the moving end shield, maintaining the airtightness of the vacuum container when moving in the axial direction of the moving end conductive rod; the bellows is disposed in the vacuum container and sleeved on the moving end conductive rod. One end of the bellows forms a sealed connection with the moving end cover plate, and the other end of the bellows forms a sealed connection with the moving end conductive rod. The bellows shield is sleeved on the outside of the bellows.

[0007] The stationary end shield is a ring structure. The inner ring is made of ceramic and is the ceramic ring part of the stationary end shield. The outer ring is made of stainless steel and is the stainless steel part of the stationary end shield. The inner circle of the magnetic ring part of the stationary end shield is the inner ring of the magnetic ring part of the stationary end shield. The outer radius of the ceramic ring part of the stationary end shield is the same as the inner radius of the stainless steel part of the stationary end shield.

[0008] The stationary end cover plate has a circular ring structure. The inner ring is made of ceramic and is the ceramic ring part of the stationary end cover plate. The outer ring is made of stainless steel and is the stainless steel part of the stationary end cover plate. The inner circle side of the ceramic ring part of the stationary end cover plate is the inner ring of the ceramic ring part of the stationary end cover plate. The outer radius of the ceramic ring part of the stationary end cover plate is the same as the inner radius of the stainless steel part of the stationary end cover plate.

[0009] The inner and outer circular sides of the ceramic ring portion of the stationary end cover plate are metallized with the inner and outer circular sides of the ceramic ring portion of the stationary end shield. The outer circular side of the ceramic ring portion of the stationary end cover plate is welded to the inner circular side of the stainless steel portion of the stationary end cover plate, and the outer circular side of the ceramic ring portion of the stationary end shield is welded to the inner circular side of the stainless steel portion of the stationary end shield.

[0010] The inner radius of the ceramic ring portion of the stationary end cover plate and the inner radius of the ceramic ring portion of the stationary end shield are the same as the radius of the stationary end conductive rod, and are welded to the stationary end conductive rod.

[0011] The sealing connection includes welding, applying adhesive, and compression gasket sealing.

[0012] The beneficial effects of adopting the above technical solution are as follows:

[0013] This invention provides a vacuum interrupter with an insulating ceramic ring. By improving the structure of the vacuum interrupter's end cover, the electric field distribution of the vacuum interrupter was studied when the stationary end conductive rod contacts the stationary end cover plate. The results show that direct contact between the stationary end cover plate and the stationary end conductive rod causes distortion of the electric field in their vicinity. Improving the contact method of the stationary end cover plate can make the electric field distribution more uniform. Connecting a ceramic ring inside the circular ring of the stationary end cover plate can significantly reduce the electric field strength caused by the stationary end cover plate, which is beneficial for optimizing the electric field. Meanwhile, the outer ring of the cover plate is made of metal, preserving its original heat dissipation capacity and mechanical strength. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the vacuum interrupter structure of this utility model;

[0015] In the diagram, 1-moving end conductive rod, 2-stationary end conductive rod, 3-moving contact, 4-stationary contact, 5-moving end cover plate, 6-stainless steel part of stationary end cover plate, 7-bellows, 8-bellows shielding cover, 9-main shielding cover, 10-insulating ceramic shell, 11-moving end shielding cover, 12-stainless steel part of stationary end shielding cover, 13-ceramic ring part of stationary end cover plate, 14-ceramic ring part of stationary end shielding cover;

[0016] Figure 2 This is a schematic diagram of the stationary end cover plate structure of this utility model;

[0017] 15 - Inner ring of the ceramic ring section of the stationary end cover plate;

[0018] Figure 3 This is a schematic diagram of the static end shielding cover structure of this utility model;

[0019] 16-Inner ring of the magnetic ring section of the stationary end shield. Detailed Implementation

[0020] The specific embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this utility model, but are not intended to limit its scope.

[0021] A vacuum interrupter with an insulating ceramic ring includes a moving end conductive rod 1, a stationary end conductive rod 2, a moving contact 3, a stationary contact 4, a moving end cover plate 5, a stainless steel portion of the stationary end cover plate 6, a bellows 7, a bellows shield 8, a main shield 9, an insulating ceramic shell 10, a moving end shield 11, a stainless steel portion of the stationary end shield 12, a ceramic ring portion of the stationary end cover plate 13, and a ceramic ring portion of the stationary end shield 14.

[0022] The main shield 9 is disposed inside the insulating ceramic shell 10, and the two are coaxially distributed. One end of the insulating ceramic shell 10 is sealed to the moving end cover plate 5, and the other end of the insulating ceramic shell 10 is sealed to the stationary end cover plate. The moving end cover plate 5, the stationary end cover plate, and the insulating ceramic shell 10 constitute a vacuum container. The moving end shield 11 is disposed outside the moving end cover plate 5. The moving contact 3 and the stationary contact 4 are disposed in the vacuum container and are arranged opposite to each other. The stationary contact 4 is fixedly disposed in the vacuum container. The stationary contact 4 is connected to one end of the stationary end conductive rod 2, and the other end of the stationary end conductive rod 2 passes through the stationary end conductive rod 2. The end cover plate forms a seal; the moving contact 3 is movably disposed in the vacuum container, the moving contact 3 is connected to one end of the moving end conductive rod 1, and the other end of the moving end conductive rod 1 passes through the moving end cover plate 5 and the moving end shield 11, maintaining the airtightness of the vacuum container when moving in the axial direction of the moving end conductive rod 1; the bellows 7 is disposed in the vacuum container and sleeved on the moving end conductive rod 1, one end of the bellows 7 forms a sealed connection with the moving end cover plate 5, the other end of the bellows 7 forms a sealed connection with the moving end conductive rod 1, and the bellows shield 8 is sleeved on the outside of the bellows 7;

[0023] The stationary end shield is a ring structure. The inner ring is made of ceramic and is the ceramic ring part 14 of the stationary end shield. The outer ring is made of stainless steel and is the stainless steel part 12 of the stationary end shield. The inner circle of the magnetic ring part 14 of the stationary end shield is the inner ring 16 of the magnetic ring part of the stationary end shield. The outer radius of the ceramic ring part 14 of the stationary end shield is the same as the inner radius of the stainless steel part 12 of the stationary end shield, ensuring its connection strength. Because the stainless steel part 12 of the stationary end shield is made of stainless steel, it ensures good heat dissipation performance, strong corrosion resistance, and maintains mechanical strength. The inner radius of the ceramic ring part 14 of the stationary end shield is the same as the radius of the stationary end conductive rod 2. The inner ring 16 of the ceramic ring part of the stationary end shield is metallized. The ceramic ring part 14 of the stationary end shield separates the stainless steel part 12 of the stationary end shield from the stationary end conductive rod 2, so large currents will not flow through and large potentials are isolated, ensuring the stability of electric field strength and potential distribution.

[0024] The stationary end cover plate has a circular ring structure. The inner ring is made of ceramic and is the ceramic ring portion 13 of the stationary end cover plate. The outer ring is made of stainless steel and is the stainless steel portion 6 of the stationary end cover plate. The inner circle of the ceramic ring portion 13 is the inner ring 15 of the ceramic ring portion 13 of the stationary end cover plate. The outer radius of the ceramic ring portion 13 of the stationary end cover plate is the same as the inner radius of the stainless steel portion 6 of the stationary end cover plate, ensuring its connection strength. Because the stainless steel portion 6 of the stationary end cover plate is made of stainless steel, it ensures good heat dissipation performance, strong corrosion resistance, and maintains mechanical strength. The inner ring 15 of the ceramic ring portion 15 of the stationary end cover plate is metallized to ensure the hardness, wear resistance, and corrosion resistance of the ceramic ring. The stainless steel portion 6 of the stationary end cover plate is separated from the stationary end conductive rod 2 by the ceramic ring portion 13 of the stationary end cover plate, so large currents will not flow through it and large potentials are isolated, ensuring the stability of the electric field strength and potential distribution.

[0025] The inner and outer circular sides of the ceramic ring portion 13 of the stationary end cover plate are metallized with the inner and outer circular sides of the ceramic ring portion 14 of the stationary end shield. The outer circular side of the ceramic ring portion 13 of the stationary end cover plate is welded to the inner circular side of the stainless steel portion 6 of the stationary end cover plate, and the outer circular side of the ceramic ring portion 14 of the stationary end shield is welded to the inner circular side of the stainless steel portion 12 of the stationary end shield.

[0026] The inner radius of the ceramic ring portion 13 of the stationary end cover plate is the same as the radius of the stationary end conductive rod 2, and the inner ring of the ceramic ring portion 13 of the stationary end cover plate is directly welded to the stationary end conductive rod 2.

[0027] The sealing connection includes welding, applying adhesive, and compression gasket sealing.

[0028] Existing vacuum interrupter stationary end cover plates and stationary end shields are made of either all-metal or all-ceramic shells. The all-ceramic shell method leads to problems such as slow heat dissipation and low mechanical strength; the all-metal method causes the metal shell to be in direct contact with the high-voltage part of the stationary end, resulting in uneven electric field distribution and partial discharge in some locations.

[0029] like Figure 1 As shown, the stationary end connection structure of the vacuum interrupter in this embodiment of the present invention includes a stationary end conductive rod 2, a stationary end cover plate ceramic ring portion 13, and a stationary end shielding cover ceramic ring portion 14. The inner ring of the stationary end cover plate ceramic ring portion 13 is directly welded to the stationary end conductive rod 2, and the inner ring 16 of the stationary end shielding cover ceramic ring portion is metallized.

[0030] like Figure 2 , Figure 3As shown, the stationary end connection structure of the vacuum interrupter in this embodiment of the present invention includes a stainless steel portion 6 of the stationary end cover plate, a ceramic ring portion 13 of the stationary end cover plate, a stainless steel portion 12 of the stationary end shielding cover, and a ceramic ring portion 14 of the stationary end shielding cover. After the outer ring of the ceramic ring portion 13 of the stationary end cover plate is metallized, it is directly welded to the inner ring of the stainless steel portion 6 of the stationary end cover plate. Similarly, after the outer ring of the ceramic ring portion 14 of the stationary end shielding cover is metallized, it is directly welded to the inner ring of the stainless steel portion 12 of the stationary end shielding cover. The above description is merely a preferred embodiment of the present disclosure and an explanation of the applied technical principles. Those skilled in the art should understand that the scope of the present invention involved in the embodiments is not limited to the technical solutions formed by specific combinations of the above-mentioned technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-mentioned technical features or their equivalent features without departing from the above-mentioned inventive concept. For example, technical solutions formed by mutually substituting the above-mentioned features with (but not limited to) technical features with similar functions disclosed in the embodiments of the present disclosure.

Claims

1. A vacuum interrupter having an insulating porcelain ring, characterized in that, The moving end conductive rod, the static end conductive rod, the moving contact, the static contact, the moving end cover plate, the bellows, the bellow shield, the main shield, the insulating porcelain shell, the moving end shield, the static end cover plate, and the static end shield; The main shield is arranged inside the insulating porcelain shell, and the two are coaxially distributed. One end of the insulating porcelain shell is sealingly connected with the moving end cover plate, and the other end of the insulating porcelain shell is sealingly connected with the static end cover plate. The moving end cover plate, the static end cover plate, and the insulating porcelain shell form a vacuum container. The moving end shield is arranged outside the moving end cover plate. The moving contact and the static contact are arranged in the vacuum container and oppositely arranged. The static contact is fixedly arranged in the vacuum container, and one end of the static contact is connected with the static end conductive rod. The other end of the static end conductive rod penetrates the static end cover plate and forms a sealing connection. The moving contact is movably arranged in the vacuum container, and one end of the moving contact is connected with the moving end conductive rod. The other end of the moving end conductive rod penetrates the moving end cover plate and the moving end shield, and the moving end conductive rod maintains the air tightness of the vacuum container when moving in the axial direction. The bellows is arranged in the vacuum container and sleeved on the moving end conductive rod. One end of the bellows is sealingly connected with the moving end cover plate, and the other end of the bellows is sealingly connected with the moving end conductive rod. The bellow shield is sleeved outside the bellows.

2. The vacuum interrupter according to claim 1, characterized in that The static end shield is a circular ring structure. The inner ring is made of ceramic and is a static end shield ceramic ring part. The outer ring is made of stainless steel and is a static end shield stainless steel part. The inner side of the magnetic ring part of the static end shield is the inner ring of the magnetic ring part of the static end shield.

3. The vacuum interrupter according to claim 2, characterized in that The static end cover plate is a circular ring structure. The inner ring is made of ceramic and is a static end cover plate ceramic ring part. The outer ring is made of stainless steel and is a static end cover plate stainless steel part. The inner side of the ceramic ring part of the static end cover plate is the inner ring of the ceramic ring part of the static end cover plate. The outer radius of the ceramic ring part of the static end cover plate is the same as the inner radius of the stainless steel part of the static end cover plate.

4. The vacuum interrupter according to claim 3, characterized in that The inner side and the outer side of the ceramic ring part of the static end cover plate are metallized, and the outer side of the ceramic ring part of the static end cover plate and the inner side of the stainless steel part of the static end cover plate are welded. The outer side of the ceramic ring part of the static end shield and the inner side of the stainless steel part of the static end shield are welded.

5. A vacuum interrupter with an insulating ceramic ring according to claim 3, characterized in that, The inner radius of the ceramic ring part of the static end cover plate and the inner radius of the ceramic ring part of the static end shield are the same as the radius of the static end conductive rod, and are welded with the static end conductive rod.

6. The vacuum interrupter with an insulating ceramic ring according to claim 1, characterized in that, The sealing connection includes welding, glue coating, and compression pad sealing.

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