CN113284773B

CN113284773B - Switch with built-in current-limiting fuse

Info

Publication number: CN113284773B
Application number: CN202110577053.XA
Authority: CN
Inventors: 万祥军; 吴斌; 戴道立; 周春龙; 施金武
Original assignee: Shanghai Junhai Special Electromechanical Equipment Technology Development Co ltd; Shanghai Electrical Apparatus Research Institute Group Co Ltd
Current assignee: Shanghai Junhai Special Electromechanical Equipment Technology Development Co ltd; Shanghai Electrical Apparatus Research Institute Group Co Ltd
Priority date: 2021-05-26
Filing date: 2021-05-26
Publication date: 2022-12-20
Anticipated expiration: 2041-05-26
Also published as: CN113284773A

Abstract

The invention discloses a switch with a built-in current-limiting fuse, which is characterized by comprising a drawing frame and a body, wherein the body is arranged in the drawing frame and comprises a base, the middle part of the front surface of the base is connected with an auxiliary contact, an electric operating mechanism, a closing electromagnet, an operating mechanism, an intelligent release and a shunt release, the upper part of the front surface of the base is connected with a large face cover and a small face cover, the back surface of the base is connected with a large bottom plate to form three independent cavities, a group of moving contact systems and a group of static contact systems are arranged in each cavity, an arc extinguishing cover is correspondingly arranged at the position right above each moving contact system, one side of the base is connected with the small bottom plate to form an independent cavity IV, and the current-limiting fuse is arranged in the cavity IV. The invention has the advantages that: the integration level is high, the installation space is small, the structure is simple, and the installation is convenient; the maintenance and the replacement are convenient, and the safety is good; the principle is simple and easy to implement, and engineering is facilitated.

Description

Switch with built-in current-limiting fuse

Technical Field

The invention relates to a switch with a built-in current-limiting fuse, belonging to the technical field of low-voltage appliances.

Background

The dc switch is one of the most important components in a dc power distribution system, and is widely applied to important power stations, substations, urban rail transit systems and ship power systems to ensure the power utilization safety of power distribution systems and electric equipment. In the prior art, in a direct current system with DC1000V or less, a method of forming a multi-break port by multi-pole series connection of an alternating current circuit breaker is often adopted to improve the working voltage of the direct current circuit breaker. Because the direct current has no zero crossing point, when the switch is switched off, the requirement on arc extinction is much higher than that of alternating current, and the switching-off time is longer. In order to meet the requirement that the short-circuit current breaking time of some special direct-current power distribution systems is extremely short, a direct-current switch is usually connected in series with a current-limiting fuse to solve the problem of rapid cut-off of direct-current short-circuit current. Under the general condition, direct current circuit breaker, current-limiting fuse independently arrange in complete set of panel, connect through outside copper bus, independent installation separately, occupation space is big, and electrical property is low, and the fuse is changed the maintenance inconvenient.

The direct current switch is an important component in a power distribution system, is usually used for protecting a power supply branch cable and electric equipment of a power system, can reliably and quickly automatically break a circuit when unallowable overload and short-circuit current occur in a loop, and is used for completing the connection and disconnection of the circuit by a direct current switch breaker when the power distribution system works normally and is overloaded; when the power distribution system is short-circuited, the current limiting fuse completes short-circuit current limiting breaking.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: how to improve the reliability, integration and maintainability of the switch in use in a power distribution system.

In order to solve the technical problem, the technical scheme of the invention is to provide a switch with a built-in current-limiting fuse, which is characterized by comprising a drawing frame and a body, wherein the body is arranged inside the drawing frame and comprises a base, the middle part of the front surface of the base is connected with an auxiliary contact, an electric operating mechanism, a closing electromagnet, an operating mechanism, an intelligent tripper and a shunt tripper, the upper part of the front surface of the base is connected with a large surface cover and a small surface cover, the back surface of the base is connected with a large bottom plate to form three independent cavities, a group of moving contact systems and static contact systems are arranged in each cavity, an arc extinguishing cover is correspondingly arranged right above each moving contact system, one side of the base is connected with the small bottom plate to form an independent cavity IV, and the current-limiting fuse is arranged in the cavity IV.

Preferably, the cavity comprises a first cavity, a second cavity and a third cavity, and an arc extinguishing chamber is arranged above each cavity.

Preferably, the current-limiting fuse is arranged on the small bottom plate, the lower end of the current-limiting fuse penetrates through the small bottom plate and is provided with a U-shaped busbar, and the upper end of the current-limiting fuse is connected to a copper bar of an adjacent static contact system through an L-shaped connecting bar.

Preferably, the base is provided with heat dissipation holes at a position right below the cavity for installing the current-limiting fuse.

Preferably, the static contact systems are arranged on the large base plate, a shunt is arranged between two adjacent static contact systems for connection, the static contact systems are connected with the moving contact system, and a U-shaped busbar is arranged at the bottom of the moving contact system.

Preferably, the auxiliary contact and the intelligent release are arranged in parallel on the front surface of the base, a closing electromagnet and a shunt release are arranged between the auxiliary contact and the intelligent release, the lower parts of the closing electromagnet and the shunt release are fixedly connected with the operating mechanism, and the lower part of the auxiliary contact is connected with the electric operating mechanism.

The working principle of the invention is as follows: the switch is mainly applied to a direct current distribution system, a main circuit of the switch is connected in series by adopting three fractures, a shunt is connected in series in the middle and used for collecting current signals of the main circuit, and the main circuit in the switch body is also connected in series with a current-limiting fuse. The switch is switched on through the operating mechanism, a switch moving contact system is closed, a main loop is switched on, and a power distribution system works normally; meanwhile, the switch can be opened through the operating mechanism, the switch moving contact system is disconnected, the main loop is disconnected, and the power distribution system is powered off and does not work. When the main loop has an unallowable overload and short-circuit current, the switch can automatically break the circuit reliably and rapidly. When the system works normally and is overloaded, the circuit breaker of the body completes the connection and disconnection of the circuit; when the system is short-circuited, the current-limiting fuse completes short-circuit current-limiting breaking, and after breaking, the current is fed back to the circuit breaker, and the circuit breaker is switched off to realize the electrical isolation of the main circuit.

The invention can provide a switch with a built-in current-limiting fuse, the switch is provided with the current-limiting fuse and is internally installed in a body of the switch, a shunt is installed on a contact system on the body and is used for detecting a current signal on a circuit, and the installation space of a power distribution system is effectively reduced through the built-in current-limiting fuse. The popularization and the application of the invention can better improve the electrical safety of the fuse and the switch installation place, reduce the installation space and improve the safety and the replaceability of the fuse used in a power distribution system.

The invention has the advantages that:

1, the integration level is high, the installation space is small, the structure is simple, and the installation is convenient;

2, the maintenance and the replacement are convenient and the safety is good;

and 3, the principle is simple and feasible, and the engineering is convenient.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic front view of the main body of the present invention;

FIG. 3 is a schematic view of the back structure of the main body of the present invention;

FIG. 4 is a schematic view of the main circuit of the main body of the present invention;

fig. 5 is a schematic view of the base structure of the present invention.

Detailed Description

In order to make the invention more comprehensible, preferred embodiments are described in detail below with reference to the accompanying drawings.

As shown in fig. 1 to 5, a switch with a built-in current-limiting fuse is characterized by comprising a drawing frame 1 and a body 2, wherein the body 2 is arranged inside the drawing frame 1, the body 2 comprises a base 14, the middle of the front surface of the base 14 is connected with an auxiliary contact 8, an electric operating mechanism 9, a closing electromagnet 10, an operating mechanism 11, an intelligent release 12 and a shunt release 13, the front surface of the base 14 is connected with a large panel cover 15 and a small panel cover 17, the back surface of the base 14 is connected with a large bottom plate 7 to form three independent cavities, each cavity is internally provided with a group of moving contact systems 21 and static contact systems 22, an arc extinguishing cover 5 is correspondingly arranged right above each moving contact system, one side of the base 14 is connected with the small bottom plate 4 to form an independent cavity four 1604, the cavity four 1604 is internally provided with the current-limiting fuse 3, the cavities comprise a cavity one 1601, a cavity two 1602 and a cavity three 1603, and the arc extinguishing cover 5 is arranged above each cavity.

The current-limiting fuse 3 is arranged on the small bottom plate 4, the lower end of the current-limiting fuse penetrates through the small bottom plate 4 to be provided with a U-shaped bus bar 19, and the upper end of the current-limiting fuse is connected to a copper bar of an adjacent static contact system 22 through an L-shaped connecting bar 18. The base 14 is provided with a heat dissipation hole 1401 at a position right below a cavity for installing the current-limiting fuse 3, the static contact system 22 is arranged on the large bottom plate 7, a shunt 20 is arranged between two adjacent static contact systems 22 for connection, the static contact system 22 and the movable contact system 21 are arranged in the cavity correspondingly, a U-shaped bus bar 19 is arranged at the bottom of the movable contact system 21, the auxiliary contact 8 and the intelligent release 12 are arranged on the front surface of the base 14 in parallel, an electromagnet 10 and a shunt release 13 are arranged between the auxiliary contact 8 and the intelligent release 12, the lower parts of the closing electromagnet 10 and the shunt release 13 are fixedly connected with the operating mechanism 11, and the lower part of the auxiliary contact 8 is connected with the electric operating mechanism 9.

Claims

1. A switch with a built-in current-limiting fuse is characterized by comprising a drawing frame (1) and a body (2), wherein the body (2) is arranged inside the drawing frame (1), the body (2) comprises a base (14), the middle of the front surface of the base (14) is connected with an auxiliary contact (8), an electric operating mechanism (9), a closing electromagnet (10), an operating mechanism (11), an intelligent tripper (12) and a shunt tripper (13), the front surface of the base (14) is connected with a large face cover (15) and a small face cover (17), the back surface of the base (14) is connected with a large bottom plate (7) to form three independent cavities, each cavity is internally provided with a group of moving contact systems (21) and a group of static contact systems (22), an arc extinguishing cover (5) is correspondingly arranged right above each moving contact system, one side of the base (14) is connected with a small bottom plate (4) to form an independent cavity four (1604), and a current-limiting fuse (3) is arranged in the cavity four (1604); the current-limiting fuse (3) is arranged on the small bottom plate (4), the lower end of the current-limiting fuse penetrates through the small bottom plate (4) to be provided with a U-shaped female bar (19), and the upper end of the current-limiting fuse is connected to a copper bar of an adjacent static contact system (22) through an L-shaped connecting bar (18); the static contact system (22) is arranged on the large bottom plate (7), a shunt (20) is arranged between two adjacent static contact systems (22) for connection, the static contact systems (22) and the movable contact system (21) are correspondingly arranged in the cavity, and a U-shaped busbar (19) is arranged at the bottom of the movable contact system (21).

2. A switch with a built-in current-limiting fuse as defined in claim 1, wherein said base (14) has a heat dissipation hole (1401) at a position right below the cavity where the current-limiting fuse (3) is installed.

3. The switch with a built-in current-limiting fuse according to claim 1, wherein the auxiliary contact (8) and the intelligent release (12) are arranged in parallel on the front surface of the base (14), a closing electromagnet (10) and a shunt release (13) are arranged between the auxiliary contact (8) and the intelligent release (12), the lower parts of the closing electromagnet (10) and the shunt release (13) are fixedly connected with the operating mechanism (11), and the lower part of the auxiliary contact (8) is connected with the electric operating mechanism (9).