A high-current DC disconnect switch

Abstract

This invention discloses a high-current DC disconnect switch, relating to the field of power electronics technology. It includes: a conductive housing with multiple parallel-connected knife switch moving contacts on both sides of the outer surface; multiple connecting rods, each hinged at its large and small ends to the multiple knife switch moving contacts on both sides of the conductive housing; and an operating mechanism assembly, the output end of which is hinged to the connecting rod body, used to drive the connecting rods to swing and synchronously rotate the knife switch moving contacts, causing them to contact or move away from the conductive housing. When the knife switch moving contacts contact the conductive housing, the disconnect switch is on; when the knife switch moving contacts move away from the conductive housing, the disconnect switch is off. This invention achieves synchronous and precise driving of multiple moving contacts, ensuring reliable contact between the moving contacts and the housing frame.

Description

Technical Field

[0001] This invention relates to the field of power electronics technology, and in particular to a high-current DC disconnect switch. Background Technology

[0002] Previously, the well-known high-current DC disconnect switches (abbreviated as DC knife switches) were all installed independently in the indoor environment of the rectifier station (or rectifier substation).

[0003] High-current DC disconnect switches must be installed inside the cabinet of an outdoor rectifier. Currently, when connecting DC knife switches to external busbars, a thin-plate layer-by-layer welding process is used.

[0004] However, during the welding process, the switch connection end plate may experience severe bending deformation due to uneven heating. This deformation leads to poor contact at the overlap (i.e., break) of the knife switch's bridging conductive plate, which in turn causes overheating and affects the normal operation of the disconnecting switch. Summary of the Invention

[0005] Therefore, it is necessary to provide a high-current DC disconnect switch to address the aforementioned technical problems.

[0006] This invention provides a high-current DC disconnect switch, comprising:

[0007] The conductive housing has multiple parallel-connected knife switch moving contacts on both sides of its exterior.

[0008] Multiple links, each with its large and small ends hinged to multiple knife switch moving contacts on both sides of the conductive housing;

[0009] The operating mechanism assembly has its output end hinged to the connecting rod body. It is used to drive the connecting rod to swing, causing the moving contact of the knife switch to rotate synchronously, so that the moving contact of the knife switch contacts or moves away from the conductive housing. When the moving contact of the knife switch contacts the conductive housing, the disconnecting switch is turned on; when the moving contact of the knife switch moves away from the conductive housing, the disconnecting switch is turned off.

[0010] Optionally, aluminum blocks are connected to both outer sides of the conductive housing, including a left aluminum block and a right aluminum block, and the thickness of both the left and right aluminum blocks is not less than 500 mm.

[0011] Optionally, the left aluminum block has a left welding surface and the right aluminum block has a right welding surface, with the width of both the left and right welding surfaces being 400mm.

[0012] Optionally, all knife switch moving contacts have a double-break bridge conductive structure with a width of 766mm.

[0013] Optionally, the operating mechanism assembly includes a motor mechanism and a manual control pin, the manual control pin extending to the outside of the operating mechanism assembly.

[0014] Optionally, the operating mechanism assembly also includes a limit unit for controlling the travel position of the multiple knife switch moving contacts.

[0015] Optionally, it also includes end insulating plates mounted on the surface and bottom of the conductive housing.

[0016] The high-current DC disconnecting switch provided in this embodiment of the invention has the following advantages compared with the prior art:

[0017] This invention employs a combined structure of a knife switch moving contact and a conductive housing, replacing the traditional lap welding process and eliminating the risk of end plate deformation caused by welding thermal stress at its source. Through the linkage design of the connecting rod and operating mechanism components, synchronous and precise driving of multiple knife switch moving contacts is achieved, ensuring reliable contact between the knife switch moving contact and the conductive housing.

[0018] Furthermore, when the drive linkage swings, it causes the moving contact of the knife switch to rotate synchronously, making the moving contact of the knife switch contact contact with or away from the conductive housing. This converts the motion into linear displacement of the moving contact of the knife switch, ensuring the consistency of the contact pressure at the break point and avoiding the contact gap caused by deformation in traditional bridging conductive plates. This not only eliminates welding process defects but also ensures the stability of the conductive circuit through mechanical linkage, significantly reducing contact resistance and heat generation, and comprehensively improving the operational reliability and safety of the disconnecting switch. Attached Figure Description

[0019] Figure 1 This is a structural diagram of a high-current DC disconnect switch provided in one embodiment;

[0020] Figure 2 A bottom view of a high-current DC disconnecting switch provided in one embodiment;

[0021] Figure 3 A side view of a high-current DC disconnecting switch provided in one embodiment;

[0022] Figure 4 This is a front view of a high-current DC disconnect switch provided in one embodiment.

[0023] Among them, 1. right aluminum block; 2. knife switch moving contact; 3. end insulating plate; 4. left welding surface; 5. left aluminum block; 6. connecting rod; 7. motor mechanism; 8. limit unit; 9. manual control shaft pin; 10. right welding surface. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0025] Existing DC disconnect switches have the following problems:

[0026] (1) The DC disconnect switch and the external busbar are connected by thin plates layer by layer by welding. During the welding process, the switch connection end plate will be severely bent and deformed due to uneven heating, resulting in poor contact and heat generation at the overlap (i.e., break) of the knife switch bridge conductive plate.

[0027] (2) The switch width needs to be minimized to be suitable for installation in the limited space inside the rectifier cabinet.

[0028] (3) Install a universal joint on the manual control shaft pin of the mechanism, fix an insulating pull rod on one side of the outward joint, and extend the insulating pull rod to the outside of the rectifier cabinet to "manually" operate the mechanism outside the rectifier cabinet. Set a suitable linkage for the knife switch so that the linkage can be used to "manually" operate the mechanism outside the rectifier cabinet.

[0029] In one embodiment, a high-current DC disconnecting switch is provided, comprising:

[0030] The conductive housing has multiple parallel-connected knife switch moving contacts 2 on both outer sides. Each knife switch moving contact 2 is a double-break bridge-type conductive structure with a width of 766mm. Aluminum blocks, including a left aluminum block 5 and a right aluminum block 1, are connected to both outer sides of the conductive housing. The thickness of both the left and right aluminum blocks is not less than 500mm. The left aluminum block 5 has a left welding surface 4, and the right aluminum block 1 has a right welding surface 10. The width of both the left welding surface 4 and the right welding surface 10 is 400mm.

[0031] Multiple links 6, the large end and small end of each link 6 are respectively hinged to multiple knife switch moving contacts 2 on both sides of the outer side of the conductive housing.

[0032] The operating mechanism assembly has its output end hinged to the connecting rod body of the connecting rod 6. It drives the connecting rod 6 to swing, causing the moving contact 2 of the knife switch to rotate synchronously, thus bringing the moving contact 2 into contact with or away from the conductive housing. When the moving contact 2 contacts the conductive housing, the disconnect switch is on; when the moving contact 2 moves away from the conductive housing, the disconnect switch is off. The operating mechanism assembly includes a motor mechanism 7 and a manual control pin 9, which extends to the outside of the operating mechanism assembly.

[0033] End insulating plate 3 is installed on the surface and bottom of the conductive housing.

[0034] Limiting unit 8 is used to control the travel position of the moving contact 2 of the knife switch.

[0035] Figure 2 This is a bottom view of a high-current DC disconnect switch. Figure 3 This is a side view of a high-current DC disconnect switch. Figure 4 This is the front view of a high-current DC disconnect switch.

[0036] Depend on Figure 2 , Figure 3 and Figure 4 We can obtain:

[0037] (1) Increase the thickness of the aluminum blocks at the two connection ends of the DC knife switch from 110mm to more than 500mm to prevent uneven heating during welding and deformation.

[0038] (2) Under the premise of meeting the current carrying requirements, the width of the knife switch is reduced from 821mm to 766mm.

[0039] (3) A linkage is used to set up a "manual" operating mechanism suitable for operation outside the rectifier cabinet.

[0040] Compared with existing DC disconnect switches, the present invention has the following advantages: (1) It solves the problem of overheating caused by poor contact due to welding deformation in DC disconnect switches.

[0041] (2) Meets the size and safety operation requirements of the DC knife switch when installed in an outdoor rectifier cabinet.

[0042] (3) Its main function is to connect and disconnect in DC power supply circuits. In electrochemical metallurgical industry (such as electrolytic aluminum, zinc, copper, etc.), chemical industry (chlor-alkali or hydrogen production), electric heating industry and other application fields, it is used for no-load connection and disconnection between DC power supply equipment and load.

[0043] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A high current DC disconnector, characterized in that include: A conductive housing, wherein multiple parallel knife switch moving contacts (2) are provided on both sides of the outer side of the conductive housing; Multiple connecting rods (6), the large end and the small end of each connecting rod (6) are respectively hinged to multiple knife switch moving contacts (2) on both sides of the outer side of the conductive housing; An operating mechanism assembly, the output end of which is hinged to the connecting rod body of the connecting rod (6), is used to drive the connecting rod (6) to swing and drive the knife switch moving contact (2) to rotate synchronously, so that the knife switch moving contact (2) contacts or moves away from the conductive housing; wherein, when the knife switch moving contact (2) contacts the conductive housing, the disconnect switch is turned on; when the knife switch moving contact (2) moves away from the conductive housing, the disconnect switch is turned off.

2. A high current DC disconnector according to claim 1, characterized in that The conductive shell is connected to aluminum blocks on both sides, including a left aluminum block (5) and a right aluminum block (1), and the thickness of the left aluminum block (5) and the right aluminum block (1) is not less than 500mm.

3. A high current DC disconnector according to claim 2, characterised in that The left aluminum block (5) has a left welding surface (4), and the right aluminum block (1) has a right welding surface (10). The width of both the left welding surface (4) and the right welding surface (10) is 400mm.

4. A high current DC disconnector according to claim 1, characterized in that The moving contacts (2) of the knife switch are all double-break bridge conductive structures with a width of 766mm.

5. A high current DC disconnector according to claim 1, characterized in that The operating mechanism assembly includes a motor mechanism (7) and a manual control pin (9) extending to the outside of the operating mechanism assembly.

6. A high current DC disconnector according to claim 5, characterised in that The operating mechanism assembly also includes a limit unit (8) for controlling the travel position of the knife switch moving contact (2).

7. A high current DC disconnector according to claim 1, characterized in that It also includes an end insulating plate (3) installed on the surface and bottom of the conductive housing.

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