Direct-current isolating switch

Abstract

The utility model discloses a direct-current isolating switch, which comprises a shell, an operating mechanism, a contact system and an arc extinguish chamber, the contact system comprises a moving contact and a static contact. A blocking structure matched with an inner cavity of the bottom plate is arranged on the moving contact, the blocking structure and the bottom plate are staggered in the opening process of the moving contact, high-pressure gas is prevented from being filled in the direction opposite to the arc extinguish chamber when current is broken, and the formed blocking structure is more beneficial to air blowing, guarantees air pressure in the arc extinguish chamber and facilitates improvement of arc voltage. The arc extinguishing effect is improved; by increasing the opening distance, the electric arc is lengthened when the current is broken, the electric arc voltage is increased, and arc extinguishing is facilitated; the upper end space of the outgoing line bar and the accessory installation space are not occupied; in addition, due to the design of the insulating plate structure, the switch provided by the utility model has more excellent insulation, and is suitable for the requirement of DC 2000V high voltage.

Description

Technical Field

[0001] The utility model relates to the field of isolating switches, in particular to a direct current isolating switch. Background Art

[0002] The isolating switch is a switch that can meet the isolation requirements of the isolator in the disconnected position and has the functions of connecting, disconnecting and isolating current;

[0003] Connection and disconnection may cause large overload currents and the current direction can be bidirectional in PV circuits; for example, several component strings are connected in parallel to the same inverter, or one or more component strings are connected in parallel to a battery. This is a typical use. Traditional DC disconnectors are generally derived from AC circuit breakers. 4-pole and 3-pole circuit breakers are connected in series or two of them are used as the main circuit of the DC disconnector; disconnectors in series are large in size and high in cost, and the temperature rise of the short-circuit bars in series is high; the method of directly taking two of them is large in size, and the arc extinguishing chamber needs to bear a large breaking pressure, which is difficult to meet the special characteristics required by photovoltaics. As the operating voltage of the power system continues to increase, some have risen to DC2000V, improving the arc extinguishing ability of the switch has become an industry focus.

[0004] At present, there are some technologies trying to solve the above problems. In a two-pole DC load switch disclosed in Chinese patent CN114743826A, the space for arranging the arc extinguishing chamber is extended toward the "direction for arranging the outgoing line row" in the depth direction to increase the space for arranging the grid, thereby improving the arc extinguishing ability. However, this solution has the disadvantage of affecting customer wiring. Another Chinese patent CN214624954U discloses a circuit breaker. By extending the space of the arc extinguishing chamber toward the "direction for arranging the operating mechanism" in the depth direction, the space of the arc extinguishing chamber is increased to improve the arc extinguishing ability. However, this operating method affects the installation of accessories originally installed above the operating mechanism, such as shunt release, closing release, undervoltage release, etc., and the traditional drive solution is not applicable. Utility Model Content

[0005] Purpose of the utility model: In order to solve the problems existing in the prior art, the utility model provides a DC isolating switch to effectively improve the arc voltage and arc extinguishing effect.

[0006] Technical solution: To achieve the above-mentioned purpose, the utility model can adopt the following technical solution: a DC disconnector, comprising a housing, an operating mechanism, a contact system and an arc extinguishing chamber; the housing comprises a base and a bottom plate, the base and the bottom plate are fixedly matched to form a housing with a plurality of isolation chambers with upper openings; the operating mechanism is installed on one side of the base of the housing, the contact system is installed in each isolation chamber, and is connected to the operating mechanism in a rotatable manner to form a main circuit of each pole of the switch; the arc extinguishing chamber is installed on the upper opening side of the housing, and covers the space of the contact system in the depth direction;

[0007] The contact system includes a moving contact and a stationary contact; the moving contact is provided with a blocking structure that matches the inner cavity of the base plate, which is intertwined with the base plate during the opening process of the moving contact to prevent high-pressure gas from filling in the opposite direction of the arc extinguishing chamber when the current is disconnected; it is more conducive to forming gas blowing, ensuring the gas pressure in the arc extinguishing chamber, and is conducive to increasing the arc voltage and improving the arc extinguishing effect.

[0008] Furthermore, the moving contact is elastically rotatably mounted on a contact support by a plurality of short contact pieces and a long contact piece; clamps are fixedly mounted on both sides of the contact support, and the rotation center of the moving contact is arranged on the clamps at a position away from the contact piece; a cover is also fixedly mounted below the contact support, and an arc structure concentric with the rotation center of the moving contact extends near the silver point below the contact piece; an arc cavity structure concentric with the rotation center of the moving contact is also arranged in the inner cavity of the bottom plate, and its radius is larger than the arc radius of the cover, and the two arc structures cooperate with each other and intersect with each other in the process of the moving contact opening from the closed state to the open state, thereby preventing the high-pressure gas from filling in the opposite direction of the arc extinguishing chamber when the current is disconnected; thereby, it is more conducive to the formation of gas blowing, ensuring the gas pressure in the arc extinguishing chamber, and is conducive to increasing the arc voltage and improving the arc extinguishing effect.

[0009] Furthermore, the long contact piece is located in the middle of the short contact piece, and the two are connected to the moving contact busbar by welding with copper braided wire.

[0010] Furthermore, the operating mechanism includes a main shaft with a drive and a cantilever fixedly connected to the main shaft, the cantilever is hingedly connected to a connecting rod, and the connecting rod is rotatably connected to the moving contact to drive the moving contact to rotate around its rotation center.

[0011] Furthermore, the main shaft rotates counterclockwise to drive the moving contact to move from the open state to the closed state; the main shaft rotates counterclockwise to drive the moving contact to move from the closed state to the open state; the length of the cantilever and the length of the connecting rod are increased, and the rotation center of the moving contact is moved toward the side close to the outgoing line row in the depth direction, thereby increasing the opening space of the contact system, that is, the switch opening distance is 30%; thereby, the layout space of the arc extinguishing chamber is increased, and more grid plates can be arranged.

[0012] Furthermore, the switch opening distance is increased, and the housing formed by the base and the bottom plate has a correspondingly larger space size in the depth direction. The base and the bottom plate are fixedly installed at appropriate positions in the depth direction, and the outer surfaces of both sides thereof are inwardly recessed in the width direction to form a groove; the installation side plate of the switch is fixedly installed inside the groove; the position of the groove in the depth direction is far away from the outgoing busbar. The purpose of this is to increase the distance between the outgoing busbar and the installation side plate, so that the electrical clearance and creepage distance are larger, the insulation is better, and thus meet the requirements of high voltage.

[0013] Furthermore, the base plate is provided with a plurality of slots for installing the insulating plate A, and the plurality of slots are respectively located on both sides of each pole output line row; the insulating plate A is provided with a slot B in the middle of the two output line rows of the same pole, and the insulating plate B is mounted on the switch through the slot.

[0014] Furthermore, the insulating plate B includes an insulating plate B1 and an insulating plate B2 which are arranged on both sides of the insulating plate A; a plurality of hooks and slots C are arranged on the left and right sides of the insulating plate B1 and the insulating plate B2; the insulating plate B1 and the insulating plate B2 are mounted on the insulating plate A through the hooks, and the insulating plate A, the insulating plate B1 and the insulating plate B2 form a mutually interlocking structure through the cooperation of the plurality of hooks and slots C to limit their freedom in all directions.

[0015] Beneficial effects: The utility model has the following advantages: (1) The two arc structures arranged on the moving contact and the bottom plate are coordinated, and they intersect with each other in the process of the moving contact opening from the closed state to the open state, preventing the high-pressure gas from filling in the opposite direction of the arc extinguishing chamber when the current is interrupted; the formed blocking structure is more conducive to the formation of gas blowing, ensuring the gas pressure in the arc extinguishing chamber, which is conducive to increasing the arc voltage and improving the arc extinguishing effect; (2) The increase in the opening distance makes the arc longer when the current is interrupted, increases the arc voltage, and is conducive to arc extinguishing; and does not occupy the upper space of the outgoing line row, which is convenient for users to connect wires; does not occupy the accessory installation space, and can use the currently mature drive and accessory solutions; effectively increases the layout space of the arc extinguishing chamber, and can arrange more grids; (3) The design of the insulating plate structure makes the switch of the utility model have better insulation and is suitable for the requirements of DC2000V high voltage. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic structural diagram of the DC isolating switch of this embodiment from a first viewing angle;

[0017] Figure 2 is a side cross-sectional schematic diagram of the present embodiment in the open state;

[0018] Figure 3is a side cross-sectional schematic diagram of the present embodiment in a closed state;

[0019] Figure 4 is a side cross-sectional schematic diagram of the embodiment when the base is hidden in the closed state;

[0020] Figure 5 Schematic diagram of the structure of the moving contact in this embodiment;

[0021] Figure 6 is a schematic structural diagram of the DC isolating switch of the present embodiment from a second viewing angle;

[0022] Figure 7 is a schematic structural diagram of the DC isolating switch of this embodiment from a third viewing angle;

[0023] Figure 8 is a schematic diagram of the structure of the cooperation between the insulating plates in this embodiment;

[0024] Fig. 9 It is a schematic diagram of the structure when all insulation panels are installed from a third viewing angle in this embodiment.

[0025] In the figure: 1. Housing; 2. Operating mechanism; 3. Contact system; 4. Arc extinguishing chamber; 5. Upper outlet row; 6. Lower outlet row; 7. Insulation board A; 8. Insulation board B; 9. Mounting side panel;

[0026] 1-1. Base; 1-2. Bottom plate; 1-3. Groove; 2-1. Mechanism main shaft; 2-2. Cantilever; 2-3. Connecting rod; 3-1. Moving contact; 3-2. Stationary contact; 1-2-1. Slot A1; 1-2-2. Slot A2; 1-2-3. Slot A3; 1-2-4. Arc cavity; 3-1-1. Contact support; 3-1-2. Short contact piece; 3-1-3. Long contact piece; 3-1-4 . Cover; 3-1-5. Moving contact busbar; 3-1-6. Clamp; 3-1-7. Moving contact rotation center; 8a. Insulation board B1; 8b. Insulation board B2; 8a-1. Slot C of insulation board B1; 8a-2. Hook of insulation board B1; 8a-3. Hook 2 of insulation board B1; 8b-1. Slot C of insulation board B2; 8b-2. Hook of insulation board B2; 8b-3. Hook 2 of insulation board B2; DETAILED DESCRIPTION

[0027] Embodiment 1:

[0028] Please refer to Figure 1-Figure 9 The utility model discloses a DC isolating switch, such as Figure 1 , 3As shown, the DC disconnector of this embodiment includes a housing 1, an operating mechanism 2, a contact system 3 and an arc extinguishing chamber 4, the housing 1 includes a base 1-1 and a bottom plate 1-2, the base 1-1 and the bottom plate 1-2 are fixedly matched to form a housing 1 with two isolation chambers with upper openings, the operating mechanism 2 is installed on one side of the housing base 1-1, the contact system 3 is installed in each isolation chamber, and is connected to the operating mechanism 2 in a rotatable manner to form a main circuit of each pole of the switch, the arc extinguishing chamber 4 is installed on the upper opening side of the housing 1, and covers the space of the contact system 3 in the depth direction, the housing 1 increases the space size in the depth direction, increases the space for opening the contact system 3, and increases the arrangement space of the arc extinguishing chamber 4;

[0029] Please refer to Figure 2-Figure 5 As shown, the contact system 3 includes a moving contact 3-1 and a stationary contact 3-2; the moving contact 3-1 is elastically rotatably mounted on a contact support 3-1-1 by a plurality of short contact pieces 3-1-2 and a plurality of long contact pieces 3-1-3, wherein the long contact piece 3-1-3 is located in the middle of the short contact piece 3-1-2, and the short contact piece 3-1-2 and the long contact piece 3-1-3 are connected to the moving contact busbar 3-1-5 by copper braided wire welding; the clamping plate 3-1-6 is fixedly mounted on both sides of the contact support 3-1-1, and the clamping plate 3-1-6 is provided with a rotation center 3-1-7 of the moving contact 3-1 head at a position away from the contact piece; the cover 3-1-4 is fixed to the contact support 3-1-1 by screws, and an arc structure concentric with the rotation center 3-1-7 of the moving contact is extended near the silver point below the contact piece; see Figure 2 and Figure 3 As shown, the inner cavity of the bottom plate 1-2 is provided with an arc cavity 1-2-4 which is concentric with the rotation center of the moving contact, and its radius is larger than the radius of the arc structure of the cover 3-1-4. The two arc structures cooperate with each other and stagger with each other during the process of the moving contact 3-1 opening from the closed state to the open state, so as to prevent the high-pressure gas from filling in the opposite direction of the arc extinguishing chamber when the current is interrupted; it is more conducive to forming gas blowing, ensuring the gas pressure in the arc extinguishing chamber, and is conducive to increasing the arc voltage and improving the arc extinguishing effect;

[0030] Please refer to Figure 2 and Figure 3 As shown, the operating mechanism 2 has a driving main shaft 2-1, a cantilever 2-2 fixedly connected to the main shaft 2-1, and a hinged connecting rod 2-3, which is rotatably connected to the moving contact 3-1 and is used to drive the moving contact 3-1 of the contact system 3 to rotate around its rotation center. The main shaft 2-1 rotates counterclockwise to drive the moving contact 3-1 to rotate from Figure 2 The open state shown moves to Figure 3 The closing state shown; the main shaft 2-1 rotates counterclockwise to drive the moving contact 3-2 from Figure 3The closing state shown moves to Figure 2 The opening state shown in the figure; by increasing the length of the cantilever 2-2, increasing the length of the connecting rod 2-3 and moving the rotating center 3-1-7 of the moving contact toward the side close to the outgoing line row in the depth direction, the opening space of the contact system is increased, that is, the switch opening distance is increased, and the opening distance is increased by 30% in this embodiment; at the same time, the arrangement space of the arc extinguishing chamber is increased, and more grid plates can be arranged;

[0031] like Figure 1 As shown, the housing 1 formed by the base 1-1 and the bottom plate 1-2 has a larger space size in the depth direction. The base 1-1 and the bottom plate 1-2 are fixedly installed at appropriate positions in the depth direction. In the width direction, the outer surfaces of both sides of the two are inwardly concave to form a groove 1-3. Figure 6 , the installation side plate 9 of the switch is fixedly installed inside the groove 1-3. The position of the groove 1-3 in the depth direction is far away from the outgoing busbar. The purpose of this is to increase the distance between the outgoing busbar 6 and the installation side plate 9, so that the electrical clearance and creepage distance are larger and the insulation is better, so as to meet the requirements of DC2000V high voltage;

[0032] Please refer to Figure 7 As shown, the bottom plate 1-2 is provided with three slots A11-2-1, A21-2-2, and A31-2-3 for installing the insulating plate A7, and the three slots are respectively located on both sides of each pole outgoing line row; the insulating plate A7 is provided with a slot B in the middle of the two outgoing line rows of the same pole, and the insulating plate B can be mounted on the switch through the slot B;

[0033] Please refer to Figure 8 As shown, the insulating plate B includes an insulating plate B18a and an insulating plate B28b which are arranged on both sides of the insulating plate A; a card slot C 8a-1 and a card hook 8a-2 are respectively arranged on the left and right sides of the insulating plate B, and a card hook 28a-3 is also arranged on the left and right sides. The insulating plate B18a and the insulating plate B28b are mounted on the insulating plate A 7 through 8a-3 and 8b-3. At the same time, the card slot C of the insulating plate B18a / the card hook of the insulating plate B28b and the insulating plate A 7 are engaged with each other. Therefore, when only the insulating plate A is installed between the poles, the insulating plate B can also be installed.

[0034] The utility model cooperates with the two arc structures arranged on the moving contact and the bottom plate, and the two arc structures are staggered in the process of the moving contact opening from the closed state to the open state, so as to prevent the high-pressure gas from filling the arc extinguishing chamber in the opposite direction when the current is interrupted; the formed blocking structure is more conducive to the formation of gas blowing, so as to ensure the gas pressure in the arc extinguishing chamber, which is conducive to increasing the arc voltage and improving the arc extinguishing effect; and by increasing the opening distance, the arc is pulled longer when the current is interrupted, the arc voltage is increased, which is conducive to arc extinguishing; and it does not occupy the upper end space of the outgoing line row, so that the user can connect the wires conveniently; it does not occupy the accessory installation space, and the currently mature drive and accessory solutions can be used; the layout space of the arc extinguishing chamber is effectively increased, and more grids can be arranged; in addition, the design of the insulating plate structure makes the switch of the utility model have better insulation, which is suitable for the requirements of DC2000V high voltage.

Claims

1. A DC isolating switch, comprising a housing, an operating mechanism, a contact system and an arc extinguishing chamber; characterized in that: The housing comprises a base and a bottom plate, wherein the base and the bottom plate are fixedly matched to form a housing having a plurality of isolation chambers with upper openings; the operating mechanism is mounted on one side of the base of the housing, the contact system is mounted in each isolation chamber and is connected to the operating mechanism in a rotatable manner to form a main circuit of each pole of the switch; the arc extinguishing chamber is mounted on the upper opening side of the housing and covers the space of the contact system in the depth direction; The contact system includes a moving contact and a stationary contact; the moving contact is provided with a blocking structure matched with the inner cavity of the base plate, which intersects with the base plate during the opening process of the moving contact to prevent high-pressure gas from filling in the opposite direction of the arc extinguishing chamber when breaking the current.

2. The DC isolating switch according to claim 1, characterized in that: The moving contact is composed of a plurality of short contact pieces and a long contact piece and is elastically rotatably mounted on a contact support; clamping plates are fixedly mounted on both sides of the contact support, and the rotation center of the moving contact is arranged on the clamping plates at a position away from the contact piece; a cover is also fixedly mounted below the contact support, and an arc structure concentric with the rotation center of the moving contact extends near the silver point below the contact piece; an arc cavity structure concentric with the rotation center of the moving contact is also arranged in the inner cavity of the bottom plate, and its radius is larger than the arc radius of the cover, and the two arc structures cooperate with each other and intersect with each other during the process of the moving contact opening from the closed state to the open state, thereby preventing the high-pressure gas from filling in the opposite direction of the arc extinguishing chamber when the current is disconnected.

3. The DC isolating switch according to claim 2, characterized in that: The long contact piece is located in the middle of the short contact piece, and the two are connected to the moving contact busbar by welding copper braided wire.

4. The DC isolating switch according to claim 1 or 2, characterized in that: The operating mechanism comprises a main shaft with a drive and a cantilever fixedly connected to the main shaft, the cantilever is hingedly connected to a connecting rod, and the connecting rod is rotatably connected to the moving contact to drive the moving contact to rotate around its rotation center.

5. The DC isolating switch according to claim 4, characterized in that: The main shaft rotates counterclockwise to drive the moving contact to move from the open state to the closed state; the main shaft rotates counterclockwise to drive the moving contact to move from the closed state to the open state; the length of the cantilever and the length of the connecting rod are increased, and the rotation center of the moving contact is moved toward the side close to the outlet row in the depth direction, thereby increasing the opening space of the contact system, that is, the switch opening distance is 30%.

6. The DC isolating switch according to claim 1 or 5, characterized in that: As the switch opening distance increases, the space size of the shell formed by the base and the bottom plate is correspondingly increased in the depth direction. The base and the bottom plate are fixedly installed at appropriate positions in the depth direction, and the outer surfaces on both sides of the two plates are recessed inward to form a groove in the width direction; the installation side plate of the switch is fixedly installed inside the groove; the position of the groove in the depth direction is away from the outlet busbar.

7. The DC isolating switch according to claim 1, characterized in that: The bottom plate is provided with a plurality of slots for installing the insulating plate A, and the plurality of slots are respectively located on both sides of each pole output line row; the insulating plate A is provided with a slot B in the middle of the two output line rows of the same pole, and the insulating plate B is mounted on the switch through the slot.

8. The DC isolating switch according to claim 7, characterized in that: The insulating plate B includes an insulating plate B1 and an insulating plate B2 which are arranged on both sides of the insulating plate A; a plurality of hooks and slots C are arranged on the left and right sides of the insulating plate B1 and the insulating plate B2; the insulating plate B1 and the insulating plate B2 are mounted on the insulating plate A through the hooks, and the insulating plate A, the insulating plate B1 and the insulating plate B2 form a mutually interlocking structure through the cooperation of the plurality of hooks and slots C to limit their freedom in all directions.

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