Contact assembly for ring main unit

Abstract

The utility model discloses a contact assembly for a ring main unit, which belongs to the technical field of intelligent power distribution equipment and comprises a movable contact knife, a voltage equalizing cover, a contact spring assembly, a static contact, an arc striking sheet and a special-shaped copper bar. The moving contact knives, the static contact and the arc striking sheet are uniformly distributed at one end of the special-shaped copper bar in three phases, each phase comprises a plurality of moving contact knives, the moving contact knives are provided with continuous contacts, and the voltage-sharing cover is arranged at one ends of the moving contact knives. The continuity of the current-carrying contact area in the closing process is ensured; through the design of the arc striking sheet, the ablation of the static contact during pre-breakdown is reduced; under the condition that the closing speed of the grounding switch is not increased, the ablation between the moving contact and the static contact is reduced, and the stability of the contact pressure and the current-carrying contact area is ensured, so that the lower contact resistance is ensured, the closing capability of the grounding switch is improved, and the reliability of the switch is ensured.

Description

Technical Field

[0001] This utility model belongs to the field of intelligent power distribution equipment technology, specifically relating to a contact assembly for a ring main unit. Background Technology

[0002] To promote the high-quality development of power distribution networks under the new circumstances and contribute to the construction of a clean, low-carbon, safe, efficient, supply-demand coordinated, flexible, and intelligent new power system, higher quality requirements are being placed on power distribution equipment. The short-circuit closing capability of grounding switches is a crucial performance indicator for ring main units (RMS), ensuring the rapid interruption of current during a short circuit and guiding the short-circuit current to ground, thus ensuring personal safety and equipment protection. However, achieving proper grounding closing is challenging. Currently, methods typically involve increasing the closing speed of the grounding switch to shorten the pre-breakdown time, thereby reducing the risk of contact erosion. However, increasing the closing speed increases closing bounce, leading to severe electrical sliding wear of the stationary contacts. Alternatively, using copper-tungsten or silver-tungsten contacts can increase the contact's erosion resistance, but this increases contact resistance and product cost. Utility Model Content

[0003] To address the shortcomings of existing technologies, this utility model provides a contact assembly for ring main units to solve the technical problems of high closing speed, high contact resistance, and high product cost in existing technologies.

[0004] The present invention adopts the following technical solution.

[0005] A contact assembly for a ring main unit includes: a moving contact blade assembly, a stationary contact blade assembly, and a shaped copper busbar. The moving contact blade assembly cooperates with the stationary contact blade assembly. The moving contact blade assembly includes: a moving contact blade, a voltage equalization cover, and a contact spring assembly. The stationary contact blade assembly includes: a stationary contact and an arc-inducing plate. The moving contact blade assembly and the stationary contact blade assembly are evenly distributed in three phases at one end of the shaped copper busbar. Each phase moving contact blade assembly includes several moving contact blades. The moving contact blades are provided with contact points, which are continuous contact points. The voltage equalization cover is located at one end of the moving contact blade. The moving contact blades and the voltage equalization cover of each phase moving contact blade assembly are connected by the contact spring assembly. The stationary contact is connected to the arc-inducing plate, and the arc-inducing plate is connected to the shaped copper busbar. A slot is provided at the middle of the front end of the arc-inducing plate.

[0006] As an improvement, each phase moving contact knife assembly includes two moving contact knives. The two moving contact knives of each phase moving contact knife assembly are symmetrically arranged on the irregular copper busbar. The two moving contact knives of each phase moving contact knife assembly are combined into a whole. The two equalizing shields of each phase moving contact knife assembly are located on both sides of this whole.

[0007] As an improvement, the contact spring assembly includes: a contact spring, a bushing, a contact spring fixing screw, and a contact spring fixing nut. The bushing is located between two moving contact blades in each phase. Both the contact spring fixing screw and the contact spring fixing nut pass through the bushing. The contact spring fixing screw and the contact spring fixing nut pass through two moving contact blades in each phase respectively. The contact spring fixing screw and the contact spring fixing nut are threaded together. Contact springs are provided between the contact spring fixing screw and the moving contact blade, and between the contact spring fixing nut and the moving contact blade.

[0008] As an improvement, both the contact spring fixing screw and the contact spring fixing nut are fitted with contact springs.

[0009] As an improvement, the contact point has a long strip-shaped cross section, and a protrusion is provided on the side of the moving contact blade away from the contact point, and the protrusion is arc-shaped.

[0010] As an improvement, the surface of the middle part of the moving contact blade is provided with reinforcing ribs, which are made by a stamping process.

[0011] As an improvement, the pressure equalization shroud has a boat-shaped structure, and the pressure equalization shroud is connected to the moving contact blade by fastening screws.

[0012] As an improvement, the stationary contact has an L-shaped structure, and the arc-inducing plate is formed by bending sheet metal.

[0013] As an improvement, the irregular copper busbar is in the shape of an inverted mountain, and the connection point between the arc-drawing plate and the irregular copper busbar is located on the lower side of the front end of the irregular copper busbar.

[0014] As an improvement, the stationary contact is provided with a first fixing screw connected to the irregular copper busbar and a second fixing screw connected to the irregular copper busbar through the arc-guiding plate. The arc-guiding plate is provided with a third fixing screw connected to the irregular copper busbar. The arc-guiding plate is located between the stationary contact and the irregular copper busbar.

[0015] The beneficial effects of this utility model are as follows: Compared with the prior art, this utility model increases the current-carrying area through a continuous contact shape design and ensures the continuity of the current-carrying contact area during the closing process; the design of the equalizing shield at the contact point serves to equalize the electric field on the one hand, and ensures the stability of the contact pressure at the contact point even when the moving contact blade deforms at high temperature; and the design of the arc-inducing plate reduces the ablation of the stationary contact during pre-breakdown; this utility model has a simple structure and is easy to assemble, and can reduce the ablation between the moving and stationary contacts without increasing the closing speed of the grounding switch, and ensure the stability of the contact pressure and current-carrying contact area, thereby ensuring low contact resistance, reducing heat generation, improving the closing capability of the grounding switch, ensuring the reliability of the switch, eliminating the need for copper-tungsten or silver-tungsten contacts, and reducing contact resistance and product cost. Attached Figure Description

[0016] Figure 1 This is an assembly drawing of a contact assembly for a ring main unit according to the present invention;

[0017] Figure 2 This is a part drawing of the moving contact blade of a contact assembly for a ring main unit according to this utility model;

[0018] Figure 3 This is an assembly drawing of a contact spring assembly for a ring main unit according to the present invention;

[0019] Figure 4 This is an assembly drawing of a stationary contact assembly for a ring main unit according to the present invention;

[0020] Figure 5 This is a diagram showing the arc-initiating position of a contact assembly for a ring main unit according to this utility model.

[0021] Figure label:

[0022] 1. Moving contact blade; 2. Equalizing cover; 3. Irregularly shaped copper busbar; 4. Contact spring assembly; 5. Stationary contact; 6. Arc ignition plate; 7. Fastening screw; 8. Contact spring fixing nut; 9. Contact spring; 10. Contact spring fixing screw; 11. First fixing screw; 12. Bushing; 101. Contact point; 102. Fixing hole; 103. Reinforcing rib; 104. Protrusion. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. The embodiments described in this application are merely some embodiments of this utility model, not all embodiments. Based on the spirit of this utility model, other embodiments obtained by those skilled in the art without creative effort are all within the protection scope of this utility model.

[0024] like Figure 1As shown, a contact assembly for a ring main unit includes: a moving contact blade 1, a pressure equalizing cover 2, a contact spring assembly 4, a stationary contact 5, an arc-guiding plate 6, and a shaped copper busbar 3. The moving contact blade 1, pressure equalizing cover 2, and contact spring assembly 4 form the moving contact assembly, while the stationary contact 5 and arc-guiding plate 6 form the stationary contact assembly. Both the moving and stationary contact assemblies are evenly distributed in three phases at one end of the shaped copper busbar 3. Each phase moving contact assembly includes two moving contact blades 1, which are symmetrically arranged and combined into a single unit. Two pressure equalizing covers 2 are located on opposite sides of this unit. The stationary contact 5 is provided with a first fixing screw 11 connected to the shaped copper busbar 3 and a second fixing screw that penetrates the arc-guiding plate 6 and connects to the shaped copper busbar 3. The arc-guiding plate 6 is provided with a... The third fixing screw connects the three phases. The arc-inducing plate 6 is disposed between the stationary contact 5 and the shaped copper busbar 3. The shaped copper busbar 3 has a first threaded hole, a second threaded hole, and a third threaded hole respectively that mate with the first fixing screw 11, the second fixing screw, and the third fixing screw. The stationary contact 5 and the arc-inducing plate 6 are symmetrical about the moving contact blade 1. The moving contact blade 1 and the equalizing cover 2 of each phase are connected by a contact spring assembly 4. The stationary contact 5 is connected to the arc-inducing plate 6, and the arc-inducing plate 6 is connected to the shaped copper busbar 3. The front end of the arc-inducing plate 6 has a slot in the middle to avoid the front end of the moving contact blade 1. When closed, the two sides of the front end of the arc-inducing plate 6 and the front end of the equalizing cover 2 form a pre-breakdown before the moving contact blade contact point 101 contacts the stationary contact 5, and withstand the arc erosion generated by the pre-breakdown, thereby protecting the moving contact blade 1 and the stationary contact 5. The arc-inducing plate is in the middle of the center. Figure 5 Inside the circle shown.

[0025] like Figure 2 and 3 As shown, the moving contact 1 is provided with a contact 101, a fixing hole 102, a reinforcing rib 103, and a protrusion 104. The moving contact 1, contact 101, reinforcing rib 103, and protrusion 104 are all made of copper. The contact 101 is a continuous contact with a long strip cross-section and a large contact area, which ensures that the contact 101 has a good contact area with the stationary contact 5 during the closing process and that the contact resistance will not increase due to changes in the contact cross-section. The surface of the middle part of the moving contact 1 is provided with a reinforcing rib 103, which is made by stamping. The reinforcing rib 103 extends along the length of the moving contact 1, which can improve the strength of the moving contact 1, enhance its resistance to deformation, and increase the local hardness of the moving contact 1. The moving contact 1 is provided with a protrusion 104 on the side away from the contact 101. The protrusion 104 is used to contact other conductive parts and is arc-shaped to ensure effective contact with other conductive parts.

[0026] The equalizing cover 2 is connected to one end of the moving contact blade 1 by a fastening screw 7. Its front end, together with the arc-initiating plate, forms an arc-initiating device. For easy fixing, the fixing hole 102 on the moving contact blade 1 is a threaded hole, which mates with the fastening screw 7. The contact spring assembly 4 includes: a contact spring 9, a bushing 12, a contact spring fixing screw, and a contact spring fixing nut 8. The bushing 12 is located between the two moving contact blades 1 in each phase, and it limits the movement of the moving contact blades 1. The contact spring fixing screw and the contact spring fixing nut 8 both pass through the bushing 12. The contact spring fixing screw and the contact spring fixing nut 8 respectively pass through the two moving contact blades 1 in each phase. The contact spring fixing screw and the contact spring fixing nut 8 are threadedly connected. Contact springs 9 are provided between the contact spring fixing screw and the moving contact blade 1, and between the contact spring fixing nut 8 and the moving contact blade 1. Contact springs 9 are fitted onto the surfaces of both the contact spring fixing screw and the contact spring fixing nut 8. The contact springs 9 are compressed by the connection between the contact spring fixing screw 10 and the contact spring fixing nut 8, thereby generating contact pressure on the moving contact blade 1. The other end of the equalizing cover 2 is elastically connected via the contact spring fixing nut 8, the contact springs 9, the contact spring fixing screw 10, and the bushing 12, ensuring that the contact pressure at the contact point does not decrease due to the distance from the contact springs 9, thus reducing the risk of excessive pressure reduction at the contact point due to high temperature. Furthermore, the equalizing cover 2 is made of stainless steel and has a boat-shaped structure, serving to uniformly distribute the electric field and ensure electrical insulation between phases.

[0027] like Figure 4 and 5 As shown, the stationary contact 5 has an L-shaped structure, which is convenient for processing. It is made of copper. The arc-inducing plate 6 is made of stainless steel and is formed by bending sheet metal. The irregular copper busbar 3 is an inverted "mountain" shape. The connection point between the arc-inducing plate 6 and the irregular copper busbar 3 is located on the lower side of the front end of the irregular copper busbar 3. This design ensures that when closed, the generated electrodynamic force is downward, which is conducive to closing and reduces the risk of failure to close completely due to electric repulsion.

[0028] Working principle:

[0029] The protrusion 104 contacts other conductive components. A slot is provided in the middle of the front end of the arc-initiating plate 6 to avoid contact with the front end of the moving contact 1. During closing, the two edges of the front end of the arc-initiating plate 6 and the front end of the equalizing cover 2 form a pre-breakdown before the contact 101 contacts the stationary contact 5, thus bearing the arc erosion generated by the pre-breakdown and protecting the moving contact 2 and the stationary contact 5. The contact 101 is a continuous contact with a long strip cross-section and a large contact area, ensuring good contact area between the contact 101 and the stationary contact 5 during closing, preventing... Because the change in the contact cross-section leads to an increase in contact resistance, the contact spring 9 is compressed by the connection between the contact spring fixing screw 10 and the contact spring fixing nut 8, thereby generating contact pressure on the moving contact blade 1. The other end of the pressure equalization cover 2 is elastically connected by the contact spring fixing nut 8, the contact spring 9, the contact spring fixing screw 10 and the bushing 12, ensuring that the contact pressure at the contact point will not decrease due to a certain distance from the contact spring 9, thus reducing the risk of the contact pressure at the contact point decreasing too much due to high temperature.

[0030] The beneficial effects of this utility model are as follows: Compared with the prior art, this utility model increases the current-carrying area through a continuous contact shape design and ensures the continuity of the current-carrying contact area during the closing process; the design of the equalizing shield at the contact point serves to equalize the electric field on the one hand, and ensures the stability of the contact pressure at the contact point even when the moving contact blade deforms at high temperature; and the design of the arc-inducing plate reduces the ablation of the stationary contact during pre-breakdown; this utility model has a simple structure and is easy to assemble, and can reduce the ablation between the moving and stationary contacts without increasing the closing speed of the grounding switch, and ensure the stability of the contact pressure and current-carrying contact area, thereby ensuring low contact resistance, reducing heat generation, improving the closing capability of the grounding switch, ensuring the reliability of the switch, eliminating the need for copper-tungsten or silver-tungsten contacts, and reducing contact resistance and product cost.

[0031] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and not to limit it. Although the utility model has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of this utility model. Any modifications or equivalent substitutions that do not depart from the spirit and scope of this utility model should be covered within the protection scope of the claims of this utility model.

Claims

1. A contact assembly for a ring main unit, characterized in that, include: Moving contact blade assembly, stationary contact blade assembly, and irregularly shaped copper busbar; The moving contact assembly cooperates with the stationary contact assembly. The moving contact assembly includes a moving contact, a pressure equalization cover, and a contact spring assembly. The stationary contact assembly includes a stationary contact and an arc-inducing plate. The moving and stationary contact assemblies are evenly distributed in three phases at one end of the irregular copper busbar. Each phase moving contact assembly includes several moving contact blades. The moving contact blades are provided with contact points, which are continuous contact points. The pressure equalization cover is located at one end of the moving contact blade. The moving contact blades and pressure equalization cover of each phase moving contact assembly are connected by a contact spring assembly. The stationary contact is connected to the arc-inducing plate, and the arc-inducing plate is connected to the irregular copper busbar. The arc-inducing plate has a slot at the middle of its front end.

2. The contact assembly for a ring main unit according to claim 1, characterized in that: Each phase moving contact knife assembly includes two moving contact knives, which are symmetrically arranged. The two moving contact knives of each phase moving contact knife assembly are combined into a whole, and the two equalizing shields of each phase moving contact knife assembly are located on both sides of this whole.

3. The contact assembly for a ring main unit according to claim 1, characterized in that, The contact spring assembly includes: a contact spring, a bushing, a contact spring fixing screw, and a contact spring fixing nut. The bushing is located between two moving contact blades in each phase. Both the contact spring fixing screw and the contact spring fixing nut pass through the bushing. The contact spring fixing screw and the contact spring fixing nut pass through two moving contact blades in each phase respectively. The contact spring fixing screw and the contact spring fixing nut are threaded together. Contact springs are provided between the contact spring fixing screw and the moving contact blade, and between the contact spring fixing nut and the moving contact blade.

4. The contact assembly for a ring main unit according to claim 3, characterized in that: Both the contact spring fixing screw and the contact spring fixing nut are fitted with contact springs.

5. A contact assembly for a ring main unit according to claim 1, characterized in that: The contact point has a long, narrow cross-section, and a protrusion is provided on the side of the moving contact blade away from the contact point. The protrusion is arc-shaped.

6. A contact assembly for a ring main unit according to claim 1, characterized in that: The surface of the middle part of the moving contact blade is provided with reinforcing ribs, which are made by stamping.

7. A contact assembly for a ring main unit according to claim 1, characterized in that: The pressure equalization shroud has a boat-shaped structure, and the pressure equalization shroud is connected to the moving contact blade by fastening screws.

8. A contact assembly for a ring main unit according to claim 1, characterized in that: The stationary contact has an L-shaped structure, and the arc-inducing plate is formed by bending sheet metal.

9. A contact assembly for a ring main unit according to claim 1, characterized in that: The irregularly shaped copper busbar is in the shape of an inverted mountain, and the connection point between the arc-drawing plate and the irregularly shaped copper busbar is located on the lower side of the front end of the irregularly shaped copper busbar.

10. A contact assembly for a ring main unit according to claim 1, characterized in that: The stationary contact is provided with a first fixing screw that connects to the irregular copper busbar and a second fixing screw that connects to the irregular copper busbar through the arc-guiding plate. The arc-guiding plate is provided with a third fixing screw that connects to the irregular copper busbar. The arc-guiding plate is located between the stationary contact and the irregular copper busbar.

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