Circuit breaker

Abstract

The utility model discloses a circuit breaker, and the circuit breaker comprises a main loop unit which is used for connecting a load and comprises a main switch; the control loop comprises an auxiliary switch and a control module which are connected with each other, the auxiliary switch and the main switch are arranged in a linkage mode and are opposite in on-off state, the control module comprises a control element and a time delay element, the time delay element is connected between the auxiliary switch and the control element, and the time delay element can conduct the auxiliary switch and the control element after preset delay time; the commutation loop unit comprises a commutation switch electrically connected with the control element, the control element is used for controlling the commutation switch, the commutation switch is connected with the main switch in parallel, and the arc extinguishing effect of the commutation loop unit is better than that of the main loop unit. According to the circuit breaker, the overall arcing time can be shortened, and the overall reliability of the circuit breaker is improved.

Description

Technical Field

[0001] The present application belongs to the technical field of electrical equipment control, and in particular, relates to a circuit breaker. Background Art

[0002] During the operation of the circuit breaker, a short circuit may occur in the line. When a short circuit occurs, the current will increase instantly, causing the switch contacts of the circuit breaker to be disconnected for a short time, thereby generating an arc. Due to the large short-circuit current, the magnetic blowing force is sufficient to blow the arc into the arc extinguishing chamber for extinguishing.

[0003] However, during the operation of the circuit breaker, a small current or critical current may cause the switch contacts of the circuit breaker to be disconnected. In this case, the current in the circuit breaker circuit is small and there is not enough magnetic blowing force. Therefore, the arc generated by the disconnection of the circuit breaker contacts cannot be blown into the arc extinguishing chamber for arc extinguishing, resulting in the arc being difficult to extinguish and a long arcing time, which affects the overall reliability of the circuit breaker. Utility Model Content

[0004] The present application provides a circuit breaker, which can shorten the overall arcing time and improve the overall reliability of the circuit breaker.

[0005] The present application provides a circuit breaker, which includes: a main circuit unit for connecting a load, the main circuit unit includes a main switch; a control circuit, including an auxiliary switch and a control module connected to each other, the auxiliary switch is linked to the main switch and has opposite on and off states, the control module includes a control element and a delay element, the delay element is connected between the auxiliary switch and the control element, and the delay element can turn on the auxiliary switch and the control element after a preset delay time; a commutation circuit unit, including a commutation switch electrically connected to the control element, the control element is used to control the commutation switch, the commutation switch is connected in parallel with the main switch, and the arc extinguishing effect of the commutation circuit unit on small DC current is better than the arc extinguishing effect of the main circuit unit on small DC current.

[0006] In the circuit breaker as above, the preset delay time of the delay element is greater than 30 ms.

[0007] In the circuit breaker as above, the main switch is a mechanical contact structure and the commutation switch is a semiconductor switch.

[0008] In the circuit breaker as above, the main switch and the commutation switch are both mechanical contact structures, the arc extinguishing medium of the main switch is air medium, and the arc extinguishing medium of the commutation switch is non-air medium.

[0009] As for the circuit breaker as above, the main switch and the commutation switch are both mechanical contact structures, the main circuit unit and the commutation circuit unit both have gas producing parts and arc extinguishing chambers, the gas producing parts have arc channels inside, the main switch and the commutation switch are both connected to the corresponding arc extinguishing chambers through the corresponding arc channels, and the flow area of ​​the arc channel in the main circuit unit is larger than the flow area of ​​the arc channel in the commutation switch.

[0010] In the circuit breaker as above, the commutation switch is the main contact of the relay, the auxiliary switch is the auxiliary contact of the relay, and the control module is the coil element of the relay.

[0011] In the circuit breaker as above, the control module further comprises an adjusting element, the adjusting element is electrically connected to the delay element, and the adjusting element is used to adjust a preset delay time of the delay element.

[0012] As the circuit breaker above, the main circuit unit also includes a first power supply element, the main switch includes two linkage switches arranged in linkage, the on-off states of the two linkage switches are the same, the first ends of the two linkage switches are respectively connected to the two ends of the first power supply element, the second ends of the two linkage switches are respectively connected to the two ends of the load, and the commutation switch is connected in parallel with one of the linkage switches.

[0013] In the circuit breaker as above, the control circuit further comprises a second power supply element connected in series with the auxiliary switch and the control module for supplying power to the auxiliary switch and the control module.

[0014] As the circuit breaker above, the circuit breaker includes multiple main circuit units and one commutation circuit unit, and the commutation circuit unit is arranged side by side with the multiple main circuit units; or, the multiple main circuit units are arranged side by side, and the commutation circuit unit is arranged on any side of the multiple main circuit units.

[0015] The circuit breaker of the present application includes a main circuit unit, a control circuit and a commutation circuit unit, wherein the main circuit unit is used to connect the load and energize the load. During the operation of the circuit breaker, the current in the main circuit unit will change with different situations. In the event of a short circuit, a larger short-circuit current will pass through. When the short-circuit current passes through, the main switch will be disconnected instantly, so that the auxiliary switch with linkage and opposite on-off state is in a connected state. At this time, the delay element is energized and starts timing. Since the Ampere force generated by the short-circuit current is large, the arc can be quickly pushed into the arc extinguishing chamber for arc extinguishing. Therefore, the main switch will recover within the preset delay time and the commutation switch will not operate.

[0016] However, when a small DC current such as a critical current passes through, the main switch will also be disconnected instantaneously, and the auxiliary switch will be in a connected state. Since the DC current does not pass through zero and the Ampere force generated by the small current is small, the arc cannot be pushed into the arc extinguishing chamber for extinguishing, which will cause the arc to burn for a long time at the contacts of the main switch. The main switch cannot be switched to a connected state, and its disconnection time exceeds the preset delay time. After the preset delay time, the delay element turns on the auxiliary switch and the control element, so that the control element is energized, and the commutation switch is closed under the control of the control element, and the small DC current can pass through the commutation switch. Since the arc extinguishing effect of the commutation circuit unit on the small DC current is better than that of the main circuit unit on the small DC current, the arc generated by the small DC current can be extinguished in time, thereby shortening the overall arcing time and improving the overall reliability of the circuit breaker. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solution of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0018] Figure 1 This is a schematic diagram of the overall circuit of a circuit breaker according to an embodiment of the present application;

[0019] Figure 2 A partial circuit diagram of a main circuit unit and a commutation circuit unit of a circuit breaker according to an embodiment of the present application;

[0020] Figure 3 This is a schematic diagram of the first structure of a circuit breaker according to an embodiment of the present application;

[0021] Figure 4 This is a second structural schematic diagram of the circuit breaker according to an embodiment of the present application.

[0022] Description of Figure Numbers:

[0023] 10. Main circuit unit; 11. Main switch; 111. Interlocking switch; 12. First power supply element; 20. Control circuit; 21. Auxiliary switch; 22. Control module; 23. Second power supply element; 30. Commutation circuit unit; 31. Commutation switch; 40. Load. DETAILED DESCRIPTION

[0024] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, rather than to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present application by illustrating the examples of the present application.

[0025] like Figures 1 to 4 As shown, an embodiment of the present application provides a circuit breaker, which includes: a main circuit unit 10, used to connect a load 40, the main circuit unit 10 includes a main switch 11; a control circuit 20, including an auxiliary switch 21 and a control module 22 connected to each other, the auxiliary switch 21 is linked to the main switch 11 and has opposite on and off states, the control module 22 includes a control element and a delay element, the delay element is connected between the auxiliary switch 21 and the control element, and the delay element can turn on the auxiliary switch 21 and the control element after a preset delay time; a commutation circuit unit 30, including a commutation switch 31 electrically connected to the control element, the control element is used to control the commutation switch 31, the commutation switch 31 is connected in parallel with the main switch 11, and the arc extinguishing effect of the commutation circuit unit 30 on small DC current is better than the arc extinguishing effect of the main circuit unit 10 on small DC current.

[0026] In specific implementation, the circuit breaker of the present application includes a main circuit unit 10, a control circuit 20 and a commutation circuit unit 30, wherein the main circuit unit 10 is used to connect the load 40 and energize the load 40. During the operation of the circuit breaker, the current in the main circuit unit 10 will change with different situations. In the event of a short circuit, a larger short-circuit current will pass through. When the short-circuit current passes through, the main switch 11 will be disconnected instantaneously, so that the auxiliary switch 21 with an interlocked state and opposite on-off state is in a connected state. At this time, the delay element is energized and starts timing. Since the Ampere force generated by the short-circuit current is large, the arc can be quickly pushed into the arc extinguishing chamber for arc extinguishing. Therefore, the main switch 11 will restore its state within the preset delay time, and the commutation switch 31 will not operate.

[0027] However, when a small DC current such as a critical current passes through, the main switch 11 will also be disconnected instantaneously, and the auxiliary switch 21 will be in a connected state. Since the DC current does not pass through zero and the Ampere force generated by the small current is small, the arc cannot be pushed into the arc extinguishing chamber for extinguishing, which will cause the arc to burn for a long time at the contact of the main switch 11. The main switch 11 cannot be switched to a connected state, and its disconnection time exceeds the preset delay time. After the preset delay time, the delay element turns on the auxiliary switch 21 and the control element, so that the control element is energized, and the commutation switch 31 is closed under the control of the control element, and the small DC current can pass through the commutation switch. Since the arc extinguishing effect of the commutation circuit unit 30 on the small DC current is better than that of the main circuit unit 10 on the small DC current, the arc generated by the small DC current can be extinguished in time, thereby shortening the overall arcing time and improving the overall reliability of the circuit breaker.

[0028] In the circuit breaker of the embodiment of the present application, the preset delay time of the delay element is greater than 30 ms.

[0029] In specific implementation, when the breaking current of the main switch 11 is a large current such as a short-circuit current, the Ampere force generated by the current is large, and the arc can be quickly pushed into the arc extinguishing chamber for arc extinguishing. The whole process can last for about 10ms to 20ms. The preset delay time of the delay element is set to be greater than 30ms, which can ensure that when a short-circuit current appears in the main circuit, the commutation circuit unit 30 will not be turned on, and the current will not be switched to the commutation circuit unit 30 for arc extinguishing; when the breaking current of the main switch 11 is a small DC current, the Ampere force generated by the current is small, and the arc generated by the breaking will be maintained between the contacts of the main switch 11 for more than 30ms. The preset delay time of the delay element is set to be greater than 30ms, and it can be judged that the current passing through the main circuit unit 10 is a small DC current, so that the delay element controls the control element and the commutation switch 31 electrically connected to the control element to turn on, so that the small DC current switches the circuit to the commutation circuit unit 30 to extinguish the small DC current arc.

[0030] By adopting the circuit breaker of the embodiment of the present application, a small DC current with a long arcing time is switched from the main circuit unit 10 to the commutation circuit unit 30. The main circuit unit 10 only needs to extinguish the arc generated by the current passing through within 30ms. The current after 30ms is transferred to the commutation circuit unit 30 with a better arc extinguishing effect, thereby reducing the overall arcing time in the circuit breaker from more than 300ms to less than 100ms.

[0031] In the circuit breaker of the embodiment of the present application, the main switch 11 is a mechanical contact structure, and the commutation switch 31 is a semiconductor switch.

[0032] In specific implementation, the mechanical contact structure selected for the main switch 11 can withstand a large current, but when disconnected, the moving contact and the static contact will separate and generate an arc. The arc needs to enter the arc extinguishing chamber to be extinguished, otherwise the arc will damage the internal structure of the circuit breaker. Therefore, the commutation switch 31 is set to a semiconductor switch, so that a small DC current passes through the main switch 11. When the arc extinguishing time is too long, the current can be transferred to the commutation circuit unit 30 and pass through the semiconductor switch. Since no arc is generated when the current passes through the semiconductor switch, the overall arcing time of the main circuit unit 10 and the commutation circuit unit 30 is shortened, thereby improving the overall reliability of the circuit breaker.

[0033] Specifically, the commutation switch 31 and the control element together form a triode element, and the conduction of the control element can turn on the commutation switch 31. It should be noted that the combination of the commutation switch 31 and the control element includes but is not limited to the form of a triode element, and other semiconductor elements can also be used for equivalent replacement.

[0034] In the circuit breaker of the second embodiment of the present application, the main switch 11 and the commutation switch 31 are both mechanical contact structures, the arc extinguishing medium of the main switch 11 is an air medium, and the arc extinguishing medium of the commutation switch 31 is a non-air medium. It should be noted that the main switch 11 and the commutation switch 31 of the mechanical contact structure will both generate arcs when disconnected, and the arc extinguishing effect of the non-air medium is better than that of the air medium.

[0035] In specific implementation, the main switch 11 adopts air medium, which reduces the space occupancy rate inside the circuit breaker, thereby reducing the overall volume of the circuit breaker. The converter switch 31 adopts a non-air medium with better arc extinguishing effect, so that when a small DC current passes through the converter switch 31, the arc can be extinguished quickly, avoiding the arc from continuing to burn at the converter switch 31, thereby reducing the arc burning time.

[0036] Specifically, the non-air medium includes but is not limited to liquid, vacuum or solid-state device and the solid-state device may be an arc-extinguishing chamber in which a plurality of arc-extinguishing grids are arranged at intervals.

[0037] The circuit breaker of the second embodiment of the present application, wherein the main switch 11 and the commutation switch 31 are both mechanical contact structures, the main circuit unit 10 and the commutation circuit unit 30 both have gas producing parts and arc extinguishing chambers, the gas producing parts have arc channels inside, the main switch 11 and the commutation switch 31 are both connected to the corresponding arc extinguishing chambers through the corresponding arc channels, and the flow area of ​​the arc channel in the main circuit unit 10 is larger than the flow area of ​​the arc channel in the commutation switch 31.

[0038] During specific implementation, the flow area of ​​the arc channel corresponding to the main switch 11 is relatively large. When a large current such as a short-circuit current passes through the main circuit unit 10, all arcs generated by the large current can be smoothly transferred to the arc extinguishing chamber for arc extinguishing. However, the arc generated by the small current cannot completely pass through the arc channel with a larger flow area due to the smaller Ampere force of the current; the flow area of ​​the arc channel corresponding to the converter switch 31 is relatively small. When the arc passes through the arc channel, it can fully contact the gas-producing parts. The gas-producing parts produce more gas, which pushes the arc into the arc extinguishing chamber for arc extinguishing, thereby increasing the arc extinguishing speed and reducing the overall arcing time.

[0039] like Figure 1 As shown, in the circuit breaker of the embodiment of the present application, the commutation switch 31 is the main contact of the relay, the auxiliary switch 21 is the auxiliary contact of the relay, and the control module 22 is the coil element of the relay.

[0040] In specific implementation, a relay is used in the circuit breaker to realize the overall control and linkage of the main circuit unit 10, the control circuit 20 and the commutation circuit unit 30. The relay is a time relay, which can realize delay control by electromagnetic separation or mechanical principle. The auxiliary switch 21 is the auxiliary contact of the relay. The conduction of the auxiliary contact can delay the coil element of the control module 22 to be energized. After the coil element is energized, the main contact of the relay can be turned on, thereby realizing the switching of the current from the main circuit unit 10 to the commutation circuit unit 30. The application of the relay is relatively simple, can realize the effect of the delay switching circuit inside the circuit breaker, and has low cost.

[0041] In the circuit breaker of the embodiment of the present application, the control module 22 further includes an adjusting element, which is electrically connected to the delay element, and the adjusting element is used to adjust a preset delay time of the delay element.

[0042] In specific implementation, by setting the adjustment element, the preset delay time of the delay element can be adjusted according to the specific performance and requirements of the circuit breaker, so that the current can be switched from the main circuit unit 10 to the commutation circuit unit 30 after the preset delay time, shortening the overall arcing time of the circuit breaker and avoiding damage to the internal parts of the circuit breaker. Therefore, the adjustable setting of the delay element enhances the overall adaptability and enables the circuit breaker to be adjusted according to the external load environment.

[0043] like Figure 2 As shown, the circuit breaker of an embodiment of the present application, wherein the main circuit unit 10 also includes a first power supply element 12, the main switch 11 includes two linkage switches 111 arranged in linkage, the on-off states of the two linkage switches 111 are the same, the first ends of the two linkage switches 111 are respectively connected to the two ends of the first power supply element 12, the second ends of the two linkage switches 111 are respectively connected to the two ends of the load 40, and the commutation switch 31 is connected in parallel with one of the linkage switches 111.

[0044] During specific implementation, the two interlocking switches 111 of the main switch 11 have the same on-off state and can simultaneously turn on or off the main circuit unit 10. When a small DC current passes through the two interlocking switches 111, the two will be disconnected at the same time for more than a preset delay time, and the converter switch 31 connected in parallel with one of the interlocking switches 111 will be turned on, and a small current will pass through the converter switch 31. The converter switch 31 can quickly extinguish the arc generated by the small current, and then close together with the other interlocking switch 111 to form a complete path, so that the entire circuit has the arc extinguishing capability of both short-circuit current and small DC current.

[0045] In the circuit breaker of the embodiment of the present application, the control circuit 20 further includes a second power supply element 23 connected in series with the auxiliary switch 21 and the control module 22 for supplying power to the auxiliary switch 21 and the control module 22 .

[0046] In a specific implementation, the second power supply element 23 can supply power to the control module 22, so that the control module 22 can achieve a delay effect and control the switching effect of the commutation switch 31, thereby realizing the complete function of the overall loop.

[0047] The circuit breaker of the embodiment of the present application includes a plurality of main circuit units 10 and a commutation circuit unit 30, and the commutation circuit unit 30 is arranged side by side with the plurality of main circuit units 10; or, the plurality of main circuit units 10 are arranged side by side, and the commutation circuit unit 30 is arranged on any side of the plurality of main circuit units 10.

[0048] When implementing it, Figure 3 As shown, multiple main circuit units 10 and commutation circuit units 30 in the circuit breaker are arranged side by side, that is, the commutation circuit unit 30 is equivalent to an accessory module of multiple main circuit units 10. This arrangement makes the internal structure of the circuit breaker more concise and also facilitates the connection between the commutation circuit unit 30 and the main circuit unit 10.

[0049] Optionally, the commutation circuit unit 30 may be arranged side by side between a plurality of main circuit units 10 or on the sides of a plurality of main circuit units 10 .

[0050] like Figure 4 As shown, the commutation circuit unit 30 is arranged on any side of a plurality of parallel main circuit units 10. In such an arrangement, the commutation circuit unit 30 can be arranged at any position that is convenient for connection and wiring, making the overall installation of the circuit breaker more convenient.

[0051] Specifically, in Figure 4In the embodiment, the volume of the commutation circuit unit 30 is smaller than the volume of the main circuit unit 10. This arrangement facilitates the installation and disassembly of the commutation circuit unit 30, while saving space inside the circuit breaker and reducing the overall volume of the circuit breaker.

[0052] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0053] The above is only a specific implementation of the present application. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, modules and units described above can refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here. It should be understood that the protection scope of the present application is not limited to this. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in this application, and these modifications or replacements should be included in the protection scope of this application.

Claims

1. A circuit breaker, characterized in that: include: A main circuit unit (10) is used to connect a load (40), wherein the main circuit unit (10) comprises a main switch (11); A control circuit (20) comprising an auxiliary switch (21) and a control module (22) connected to each other, wherein the auxiliary switch (21) is arranged in linkage with the main switch (11) and has opposite on and off states, and the control module (22) comprises a control element and a delay element, wherein the delay element is connected between the auxiliary switch (21) and the control element, and the delay element can switch on the auxiliary switch (21) and the control element after a preset delay time; A commutation circuit unit (30) comprises a commutation switch (31) electrically connected to the control element, the control element being used to control the commutation switch (31), the commutation switch (31) being connected in parallel with the main switch (11), the commutation circuit unit (30) having a better arc extinguishing effect on a small direct current than the main circuit unit (10) having a better arc extinguishing effect on a small direct current.

2. The circuit breaker according to claim 1, characterized in that: The preset delay time of the delay element is greater than 30ms.

3. The circuit breaker according to claim 1, characterized in that: The main switch (11) is a mechanical contact structure, and the commutation switch (31) is a semiconductor switch.

4. The circuit breaker according to claim 1, characterized in that: The main switch (11) and the commutation switch (31) are both mechanical contact structures; the arc extinguishing medium of the main switch (11) is an air medium, and the arc extinguishing medium of the commutation switch (31) is a non-air medium.

5. The circuit breaker according to claim 1, characterized in that: The main switch (11) and the commutation switch (31) are both mechanical contact structures, the main circuit unit (10) and the commutation circuit unit (30) both have a gas-generating component and an arc-extinguishing chamber, the gas-generating component has an arc channel inside, the main switch (11) and the commutation switch (31) are both connected to the corresponding arc-extinguishing chamber through the corresponding arc channel, and the flow area of ​​the arc channel in the main circuit unit (10) is greater than the flow area of ​​the arc channel in the commutation switch (31).

6. The circuit breaker according to claim 4 or 5, characterized in that: The commutation switch (31) is a main contact of a relay, the auxiliary switch (21) is an auxiliary contact of a relay, and the control module (22) is a coil element of a relay.

7. The circuit breaker according to claim 2, characterized in that: The control module (22) also includes an adjusting element, which is electrically connected to the delay element and is used to adjust the preset delay time of the delay element.

8. The circuit breaker according to claim 1, characterized in that: The main circuit unit (10) further comprises a first power supply element (12); the main switch (11) comprises two linkage switches (111) arranged in linkage; the two linkage switches (111) have the same on-off state; the first ends of the two linkage switches (111) are respectively connected to the two ends of the first power supply element (12); the second ends of the two linkage switches (111) are respectively connected to the two ends of the load (40); and the commutation switch (31) is connected in parallel with one of the linkage switches (111).

9. The circuit breaker according to claim 1, characterized in that: The control circuit (20) further comprises a second power supply element (23) connected in series with the auxiliary switch (21) and the control module (22) and used for supplying power to the auxiliary switch (21) and the control module (22).

10. The circuit breaker according to claim 1, characterized in that The circuit breaker comprises a plurality of the main circuit units (10) and a commutation circuit unit (30), wherein the commutation circuit unit (30) and the plurality of the main circuit units (10) are arranged side by side; or, the plurality of the main circuit units (10) are arranged side by side, and the commutation circuit unit (30) is arranged on any side of the plurality of the main circuit units (10).

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