CN111863517A - A new type of DC high-speed circuit breaker - Google Patents

Abstract

The invention discloses a novel direct current high-speed circuit breaker, belonging to the technical field of circuit protection equipment, the circuit breaker comprises: an insulating housing; the inside of insulating housing is equipped with: the device comprises an overcurrent tripping device, a main electrical loop, a closing device, an auxiliary feedback device, an arc extinguishing device and an operating component; the auxiliary feedback device is electrically connected with the main electrical loop; the overcurrent tripping device and the main electrical loop are respectively electrically connected with an external power supply device; the operating component is connected with the main electrical loop and is matched with the switching-on device, the auxiliary feedback device and the arc extinguishing device for use, and after the switching-on device acts, the action effect of driving other components is achieved. The shock absorber has good vibration resistance and mechanical impact resistance in the moving contact action process; secondly, the invention modularly assembles the components, and the structure between the components is compact.

Description

A new type of DC high-speed circuit breaker

technical field

The invention relates to the technical field of circuit protection equipment, in particular to a novel DC high-speed circuit breaker.

Background technique

In the field of power distribution, driven by modern power electronics technology and distributed power sources, the DC distribution network has a huge development prospect. Common distributed power sources can generate direct current or become direct current after rectification. If these power sources are connected to the DC distribution network, the commutation link will be greatly saved;

Compared with the AC distribution network, the DC distribution network has many technical and economic advantages such as low line cost, low transmission loss, and high power supply reliability. As a DC protection device, the DC circuit breaker is of great significance to ensure the safe operation of the DC distribution network. In order to effectively suppress the spread of fault current, ensure the safe operation of the DC transmission and distribution network and the normal operation of the equipment, the DC circuit breaker will become an effective or even the only technology. means.

According to their different arc extinguishing principles, mechanical DC circuit breakers can be divided into vacuum circuit breakers, sulfur hexafluoride circuit breakers, more oil (less oil) circuit breakers, compressed air circuit breakers, magnetic blower circuit breakers and air circuit breakers. At present, vacuum circuit breakers and sulfur hexafluoride circuit breakers have largely replaced other circuit breakers and have been widely used in power systems.

However, the structure of the existing circuit breaker is relatively simple, and the volume is large and the installation space is limited; secondly, the existing circuit breaker has a single function, in order to protect the normal operation of the circuit, devices with different functions are connected, thereby increasing the fault frequency of the circuit breaker , reducing the service life and safety of the circuit breaker, for which we provide a modular air circuit breaker.

SUMMARY OF THE INVENTION

In view of the above problems, the present invention provides a novel DC high-speed circuit breaker.

On the one hand, the technical solution adopted by the present invention is a new type of DC high-speed circuit breaker, comprising: an insulating housing; the insulating housing is provided with: an overcurrent trip device, a main electrical circuit, a closing device, and an auxiliary feedback devices, arc extinguishing devices and operating components;

The auxiliary feedback device is electrically connected with the main electrical circuit;

The overcurrent tripping device and the main electrical circuit are respectively electrically connected with the external power supply device;

The operating member is connected with the main electrical circuit and used in conjunction with the closing device, the auxiliary feedback device and the arc extinguishing device. After the closing device is actuated, the action effect of driving the closing device, the auxiliary feedback device and the arc extinguishing device is achieved. .

Further, transverse and longitudinal bearing plates are arranged inside the insulating casing, and the bearing plates are integrally formed with the insulating casing.

Further, the main electrical circuit mainly includes: a moving contact, a static contact, an arc angle, a fork and a protection resistor;

The operating member mainly includes: a connecting rod;

Both the movable contact and the static contact are softly connected with the wire piles in the insulating housing;

Wherein, the lower end of the movable contact is hinged with the laterally arranged bearing plate inside the insulating housing, and the right side is hinged with the upper end of the connecting rod;

A sleeve is nested at the lower end of the connecting rod, and the upper end of the sleeve is hinged with a bearing plate arranged laterally inside the insulating housing; and a first spring is sleeved on the connecting rod, and the first spring is limited to the sleeve the lower end of the barrel;

the static contact is connected to the arc-starting angle, and the static contact is located at the lower end of the arc-starting angle;

One end of the shift fork is connected with the closing device, and the other end is in contact with the movable contact when the shift fork moves horizontally.

Further, the overcurrent tripping device mainly includes: a moving iron core, a lever and a magnetic element, and the overcurrent tripping device is connected in series with the main electrical circuit;

The upper end of the moving iron core is connected to one end of the lever, and the lever is connected to the inside of the insulating housing with rotation;

Wherein, when the magnetic element imparts a magnetic force to the movable iron core, the other end of the lever is in contact with the movable contact during the movement of the movable iron core.

Further, the auxiliary feedback device mainly includes: auxiliary contacts, which are electrically connected to the main electrical circuit.

Further, the arc extinguishing device mainly includes: an arc extinguishing cover, an arc striking angle, and a de-ionization partition;

The arc striking grids are symmetrically arranged on both sides of the arc extinguishing cover, and the de-electricity isolation plates are symmetrically arranged on both outer sides of the arc striking grids; and the whole formed by the three is arranged at the upper end of the arc striking angle.

Further, shock absorbers are provided on both sides of the moving contact;

Among them, one of the shock absorbers is located below the left side of the moving contact, and the lower end is connected to a bearing plate arranged laterally in the insulating housing; the shock absorber on the right side of the moving contact is located above the right side of the moving contact, and the shock absorber The device is located on a carrier plate arranged longitudinally in the insulating housing.

Furthermore, the lower end of the fork is connected with a second spring, and the lower end of the second spring is connected with the laterally arranged bearing plate.

Furthermore, a semicircular groove is provided at the connection between the lower end of the movable contact and the corresponding bearing plate, and the lower end of the movable contact rotates in the semicircular groove when the movable contact moves.

On the other hand, the present invention provides a working method of a novel DC high-speed circuit breaker, the method comprising:

Step 1: Closing, the circuit breaker closing and holding device adopts a solenoid type electromagnet, the coil is energized through the closing command, and the moving iron core drives the moving contact to close through the shifting fork. After a delay of 0.5 to 1s, the control loop automatically Connect the holding resistance, the iron core and the moving contact are kept in the closed position;

Step 2, open the gate, the coil is de-energized through the opening command, the recovery spring forces the iron core and the fork to reset, and the moving contact is disconnected;

Step 3, overcurrent tripping and arc extinguishing, when the circuit is overloaded or short-circuited, the flowing current is greater than the static setting value, and the overcurrent tripping device acts, forcing the shift fork to release the moving contact upwards, and the moving contact is disconnected. Due to the action of the main circuit's own magnetic field, the arc current blows the arc into the arc extinguishing chamber, and the metal grid in the arc extinguishing device separates the arc into many short arcs, which are freed in the isolation plate to extinguish the arc.

Advantages of the present invention:

First of all, this technical solution diversifies the functions of the circuit breaker. When the circuit is loaded or short-circuited, the overcurrent tripping device can be used to disconnect the contacts in the circuit in time to protect the circuit. The arc generated when the contact is disconnected is introduced into the arc extinguishing device through the arc striking angle, which can extinguish the arc, and the set auxiliary feedback device can timely feedback the signal in the circuit to the processor; secondly, through the set auxiliary feedback device The shock absorber can buffer the moving contact during closing and opening, reducing the force on the moving contact. Furthermore, the circuit breaker product is small in size, compact in structure, light in weight, long in mechanical and electrical life, simple in structure and low in maintenance requirements.

Description of drawings

The accompanying drawings constituting a part of the present application are used to provide further understanding of the present invention, and the exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention.

1 is a schematic diagram of a gate opening structure according to an embodiment of the present invention;

Fig. 2 is the closed gate structure diagram of the embodiment of the present invention;

Fig. 3 is the DC control principle diagram of the embodiment of the present invention;

4 is an AC control diagram of an embodiment of the present invention;

FIG. 5 is a wiring diagram of an auxiliary switch according to an embodiment of the present invention.

Reference number:

101-bearing plate; 2-fork; 3-moving contact; 4-connecting rod; 5-auxiliary contact; 6-shock absorber; 7-lever; 8-moving iron core; 9-static contact; 10 - arc extinguishing cover; 11 - arc striking angle; 12 - arc striking grid; 13 - de-ionization partition; 14 - semicircular groove; 15 - first spring.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present 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 only used to explain the present invention, but not to limit the present invention.

Referring to Figure 1 to Figure 5, as shown in Figure 1 to Figure 5, the insulating housing; the interior of the insulating housing is provided with: overcurrent tripping device, main electrical circuit, closing device, auxiliary feedback device, arc extinguishing device and operation moving member;

The auxiliary feedback device is electrically connected with the main electrical circuit;

The overcurrent release device and the main electrical circuit are respectively electrically connected with the external power supply device;

The operating member is connected with the main electrical circuit, and is used in conjunction with the closing device, the auxiliary feedback device, and the arc extinguishing device. After the closing device is actuated, the action effect of driving other components is achieved.

It should be noted that the above components are all commercially available components, and the specific working principle and parameter setting refer to the prior art; for example, the tripping mechanism is an important part of the During the switching process and when it is in the closing position, the tripping mechanism acts like a fulcrum of force. When the circuit breaker automatically trips, the tripping mechanism is manipulated by the tripping device to release this fulcrum and make the circuit breaker enter the free opening. state. In layman's terms, the lever and spring mechanism in the switch are supported by the release. Once the release is activated, the lever and spring mechanism in the switch will reset freely, that is, the switch will trip;

Among them, in this technical solution, specifically, when the current in the main electrical circuit exceeds the tripping set value, the magnetic element in the tripping device generates a magnetic field, and the magnetic field force pushes the moving iron core to move upward, and the moving iron core moves upwards. During the upward movement, the lever presses the fork down to the right end. During this process, the pulling and inserting return position, and the pull rod returns to the position under the action of the first spring, so that the pull rod pulls the moving contact to separate from the static contact. The role of the protection circuit.

In addition, by adding structures to existing components with different functions and making more superior designs in connection methods and connection structures, this solution has more superior functions compared to components in the prior art. At the same time, different components are integrated into a module; for details, refer to the accompanying drawings and working principles of the description.

In an embodiment of the present invention, a lateral and vertical carrying board 101 is provided inside the insulating housing, and the carrying board 101 and the insulating housing are integrally formed.

In an embodiment of the present invention, the main electrical circuit mainly includes: a moving contact 3, a static contact 9, an arc striking angle 11, a fork 2 and a protection resistor;

The operating member mainly includes: connecting rod 4;

Both the moving contact 3 and the static contact 9 are softly connected to the wire piles in the insulating housing;

Wherein, the lower end of the movable contact 3 is hinged with the laterally arranged bearing plate inside the insulating housing, and the right side is hinged with the upper end of the connecting rod 4;

A sleeve is nested at the lower end of the connecting rod 4, and the upper end of the sleeve 401 is hinged with the bearing plate 101 arranged laterally inside the insulating housing; and a first spring 15 is sleeved on the connecting rod 4, and the first spring 15 is limited to the sleeve 401 lower end;

The static contact 9 is connected with the arc striking angle 11, and the static contact 9 is located at the lower end of the arc striking angle 11;

One end of the fork 2 is connected with the closing device, and the other end is in contact with the movable contact 3 when the fork 2 moves horizontally.

In an embodiment of the present invention, the overcurrent tripping device mainly includes: a moving iron core 8, a lever 7 and a magnetic element, and the overcurrent tripping device is connected in series with the main electrical circuit;

The upper end of the moving iron core 8 is connected with one end of the lever 7, and the lever 7 is rotatably connected inside the insulating housing;

Wherein, when the magnetic element imparts a magnetic force to the movable iron core 8 , the other end of the lever 7 is in contact with the movable contact 3 during the movement of the movable iron core 8 .

In an embodiment of the present invention, the auxiliary feedback device mainly includes: an auxiliary contact 5, which is connected to the connecting rod 4 and is electrically connected to the main electrical circuit.

It should be noted that the auxiliary switch in the auxiliary feedback device is a part of the main switch, and is configured in high-voltage or medium-voltage circuit breakers, isolation switches and other power equipment as the opening, closing, signal control and interlocking of the secondary control circuit. It can also be used as combination switch and transfer switch; the reason why the auxiliary switch has the word "auxiliary" in its name is because it is not an independent switch, it is an auxiliary breaking and connecting switch in the control system. The carrier auxiliary feedback device realizes the function of communication and interlocking.

In an embodiment of the present invention, the arc extinguishing device mainly includes: an arc extinguishing cover 10, an arc ignition grid 12, and a de-ionization partition 13;

The arc-striking grids 12 are symmetrically arranged on both sides of the arc extinguishing cover 10 , and the de-electricity isolation plates 13 are symmetrically arranged on both outer sides of the arc-striking grids 12 ;

In an embodiment of the present invention, shock absorbers 6 are provided on both sides of the movable contact 3;

Among them, a shock absorber 6 is located below the left side of the movable contact 3, and the lower end is connected to the bearing plate 101 arranged laterally in the insulating housing; the shock absorber 6 on the right side of the movable contact 23 is located above the right side of the movable contact 3, And the shock absorber 6 is located on the bearing plate 101 longitudinally arranged in the insulating housing.

In an embodiment of the present invention, the lower end of the shift fork 2 is connected with a second spring, and the lower end of the second spring is connected with the laterally disposed bearing plate 101 .

It should be noted that the provided shock absorber 6 mainly prevents the movable contact 3 from causing damage to the structure in contact with it when the movable contact 3 stops after rotating. Therefore, the above-mentioned problems can be avoided by the provided shock absorber 6 .

In an embodiment of the present invention, a semicircular groove 14 is provided at the connection between the lower end of the movable contact 3 and the corresponding carrier plate 101 .

It should be noted that the semicircular groove 14 is provided at the connection of the lower end of the movable contact 3. On the one hand, when the movable contact 3 rotates, the speed during the rotation is fast and stops when it rotates to the right. Therefore, the semicircular groove 14 provided at the lower end of the moving contact 3 can limit its rotation angle, thereby weakening the acting force; on the other hand, the lower end of the moving contact 3 is equivalent to rotating in a groove , its motion state is more stable.

The working method of a novel DC high-speed circuit breaker provided by the present invention:

Step 1: Closing, the circuit breaker closing and holding device adopts a solenoid type electromagnet, the coil is energized through the closing command, and the moving iron core drives the moving contact to close through the shifting fork. After a delay of 0.5 to 1s, the control loop automatically Connect the holding resistance, the iron core and the moving contact are kept in the closed position;

Specifically, when the circuit breaker receives the closing pulse command, the closing device pushes the shift fork, and the shift fork pushes the moving contact to close, and at the same time, a contact pressure is generated between the moving contact and the static contact; the connecting rod connecting the moving contact drives the The auxiliary contact is displaced, and the shock absorber can dampen the impact force generated during the closing process;

Closing hold: When the main contact is closed, the closing device maintains the contact voltage with a small holding current;

Step 2, open the gate, the coil is de-energized through the opening command, the recovery spring forces the iron core and the fork to reset, and the moving contact is disconnected;

Specifically, the circuit breaker cuts off the holding current after receiving the opening command. At this time, the fork rod of the circuit breaker moves in the direction of the closing device under the action of the second spring reaction; while the first spring opens the moving contact, the connecting rod drives The auxiliary contact is displaced, and the shock absorber can dampen the impact force generated during the opening process.

Step 3, overcurrent tripping: when the main circuit current exceeds the high current tripping set value, a magnetic field is generated in the tripping device, the magnetic field force will lift the moving iron core to move upward, and trigger the lever to press the fork down to release moving contact;

Step 4: Extinguishing the arc, the arc current generated by the breaking of the moving contact blows the arc into the arc extinguishing chamber due to the action of the main circuit's own magnetic field, and the metal grid in the arc extinguishing device separates the arc into many short arcs, which are isolated The plate is freed and the arc is extinguished.

The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection of the present invention. within the range.

Claims (10)

1. A novel direct current high speed circuit breaker, characterized by comprising: an insulating housing; the insulating shell is internally provided with: the device comprises an overcurrent tripping device, a main electrical loop, a closing device, an auxiliary feedback device, an arc extinguishing device and an operating component;

the auxiliary feedback device is electrically connected with the main electric loop;

the overcurrent tripping device and the main electrical loop are respectively electrically connected with an external power supply device;

the operating component is connected with the main electrical loop and is matched with the switching-on device, the auxiliary feedback device and the arc extinguishing device for use, and after the switching-on device acts, the action effect of driving the switching-on device, the auxiliary feedback device and the arc extinguishing device is achieved.

2. The novel direct current high-speed circuit breaker according to claim 1, characterized in that a transverse and longitudinal bearing plate (101) is arranged inside the insulating housing, and the bearing plate (101) is integrally formed with the insulating housing.

3. The novel dc high speed circuit breaker according to claim 1, wherein said main electrical circuit essentially comprises: the moving contact (3), the static contact (9), the arc striking angle (11), the shifting fork (2) and the protective resistor;

the operating member mainly includes: a connecting rod (4);

the moving contact (3) and the static contact (9) are in flexible connection with the wire pile in the insulating shell;

the lower end of the moving contact (3) is hinged with a transversely arranged bearing plate in the insulating shell, and the right side surface of the moving contact is hinged with the upper end of the connecting rod (4);

the lower end of the connecting rod (4) is nested with a sleeve, and the upper end of the sleeve (401) is hinged with a bearing plate (101) transversely arranged in the insulating shell; a first spring (15) is sleeved on the connecting rod (4), and the first spring (15) is limited at the lower end of the sleeve (401);

the static contact (9) is connected with the arc striking angle (11), and the static contact (9) is positioned at the lower end of the arc striking angle (11);

one end of the shifting fork (2) is connected with the closing device, and the other end of the shifting fork (2) is contacted with the moving contact (3) when the shifting fork moves horizontally.

4. The novel direct current high speed circuit breaker according to claim 1, characterized in that the over-current trip device mainly comprises: the overcurrent tripping device is connected in series with the main electric appliance loop;

the upper end of the movable iron core (8) is connected with one end of the lever (7), and the lever (7) is rotatably connected inside the insulating shell;

when the magnetic element gives magnetic force to the movable iron core (8), the other end of the lever (7) is in contact with the movable contact (3) in the moving process of the movable iron core (8).

5. The novel direct current high speed circuit breaker according to any one of claims 1-3, characterized in that the auxiliary feedback device mainly comprises: an auxiliary contact (5), said auxiliary contact (5) being connected to a link (4) and being electrically connected in said main electrical circuit.

6. The novel direct current high speed circuit breaker of claim 1, characterized in that the arc extinguishing device mainly comprises: an arc extinguishing shield (10), an arc striking grid sheet (12) and a deionization baffle plate (13);

the arc striking grid pieces (12) are symmetrically arranged on two sides of the arc extinguishing chamber (10), and the de-electrifying isolation plates (13) are symmetrically arranged on two outer sides of the arc striking grid pieces (12); and the three components are integrally arranged at the upper end of the arc striking angle (11).

7. The novel direct current high-speed circuit breaker according to claim 1, characterized in that shock absorbers (6) are arranged on both sides of the moving contact (3);

the shock absorber (6) is positioned below the left side of the moving contact (3), and the lower end of the shock absorber is connected with a bearing plate (101) transversely arranged in the insulating shell; the shock absorber (6) on the right side of the moving contact (23) is positioned above the right side of the moving contact (3), and the shock absorber (6) is positioned on a bearing plate (101) longitudinally arranged in the insulating shell.

8. The novel direct current high-speed circuit breaker according to claim 1, characterized in that a second spring is connected to the lower end of the shift fork (2), and the lower end of the second spring is connected with a transversely arranged bearing plate (101).

9. The novel direct current high-speed circuit breaker according to claim 3, characterized in that a semicircular groove (14) is formed at the connection position of the lower end of the movable contact (3) and the corresponding bearing plate (101), and when the movable contact (3) acts, the lower end of the movable contact rotates in the semicircular groove (14).

10. A novel working method of a dc high-speed circuit breaker, which is applied to the novel dc high-speed circuit breaker of any one of claims 1 to 9, wherein the method comprises:

step 1, switching on, wherein a circuit breaker closing maintaining device adopts a solenoid electromagnet, a coil is electrified through a switching-on instruction, a moving iron core of the circuit breaker drives a moving contact to be closed through a shifting fork, a control loop is automatically connected into a maintaining resistor after 0.5-1 s of time delay, and the iron core and the moving contact are maintained at a closed position;

step 2, switching off, wherein the coil is powered off through a switching-off command, the first spring forces the iron core and the shifting fork to reset, and the moving contact is disconnected;

and 3, overcurrent tripping and arc extinguishing, wherein when the loop is overloaded or short-circuited, the overcurrent tripping device acts to force the shifting fork to upwards release the moving contact, the arc current generated by the disconnection of the moving contact blows the arc into the arc extinguishing chamber under the action of the magnetic field of the main circuit, and the metal grid sheet in the arc extinguishing device divides the arc into a plurality of short arcs, dissociates the short arcs in the de-electrifying isolation plate and extinguishes the arc.

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