Residual current circuit breaker and system including same

Abstract

A residual current circuit breaker and a system including the same are provided. The residual current circuit breaker comprises a first switch which is connected in series between a power supply and a load of the residual current circuit breaker; the second switch is connected in series between the standby power supply and the load; the control component responds to the situation that the residual current of a main loop of the residual current circuit breaker exceeds a preset threshold value and controls the first switch to be switched off and the second switch to be switched on, the voltage of the standby power supply is higher than the minimum value of the voltage needed by the load to work and lower than the maximum value of the safety voltage, and the voltage of the standby power supply is higher than the minimum value of the voltage needed by the load to work and lower than the maximum value of the safety voltage. And the first switch and the second switch are mutually exclusive.

Description

Technical Field

[0001] The present disclosure relates to a residual current circuit breaker and a system for residual current protection, the system comprising the residual current circuit breaker. Background Art

[0002] A residual current circuit breaker (also known as a leakage protection device) is a grounding protection device used to prevent accidents caused by electric shock and leakage. When the residual current circuit breaker detects that the residual current (also known as leakage current) in its main circuit exceeds its setting value or a person and / or animal is electrocuted, the residual current circuit breaker can quickly perform a tripping action to cut off the accident power supply, thereby protecting the safety of people, animals and loads. However, in certain application scenarios of residual current circuit breakers, unexpected secondary accidents may occur because the load suddenly stops working due to the power supply being cut off as the residual current circuit breaker trips. For example, in an application scenario where the load is a lighting device, the sudden cessation of the lighting device may cause secondary accidents to pedestrians, vehicles, etc. For another example, in an application scenario where the load is a monitoring device, the sudden cessation of the monitoring device may result in the missing of critical monitoring information. Summary of the invention

[0003] In view of the above situation, it is necessary to consider a solution that can meet the requirements of residual current protection while also meeting the minimum load working requirements to avoid secondary accidents. For example, in the scenario where the residual current circuit breaker is used for lighting equipment, it is expected that the solution can prevent both electric shock accidents caused by residual current and traffic accidents caused by complete loss of lighting of the lighting equipment.

[0004] One aspect of the present disclosure provides a residual current circuit breaker. The residual current circuit breaker includes: a first switch connected in series between the power supply of the residual current circuit breaker and the load; a second switch connected in series between the backup power supply and the load; and a control component, in response to the residual current of the main circuit of the residual current circuit breaker exceeding a predetermined threshold, controlling the first switch to be disconnected and the second switch to be connected, wherein the voltage of the backup power supply is higher than the minimum value of the voltage required for the load to work and lower than the maximum value of the safety voltage, and wherein the first switch and the second switch are mutually exclusive.

[0005] Optionally, the backup power supply is located outside the residual current circuit breaker, and the residual current circuit breaker further comprises: an external interface for connecting to the backup power supply, and the second switch is connected between the external interface and the load.

[0006] Optionally, the backup power supply is located inside the residual current circuit breaker as a part thereof.

[0007] Optionally, the backup power supply is provided by a voltage converter, the input end of the voltage converter is connected to the incoming line end of the residual current circuit breaker to convert the voltage of the power supply into a voltage higher than the minimum value of the voltage required for the load to operate and lower than the maximum value of the safety voltage, and the second switch is connected between the output end of the voltage converter and the load.

[0008] Optionally, the voltage converter performs conversion in response to receiving a trigger signal for triggering it to perform conversion.

[0009] Optionally, the first switch, the second switch and the control component are provided by a dual power supply switch.

[0010] Optionally, the first switch and the second switch are solid-state switches.

[0011] Another aspect of the present disclosure provides a residual current protection system, the system comprising a power supply, a load, and a residual current circuit breaker according to one of the aforementioned items.

[0012] Optionally, the load includes a plurality of lighting devices and a plurality of drivers respectively used to drive each of the plurality of lighting devices.

[0013] Optionally, each of the multiple drivers provides driving power to the corresponding lighting device that enables the lighting device to illuminate at a minimum illumination level when detecting that its supply voltage is lower than a predetermined voltage threshold, and the predetermined voltage threshold is the highest value of the voltage of the backup power supply.

[0014] In this way, the residual current circuit breaker according to the embodiment of the present disclosure switches the load from the power supply to the backup power supply when the residual current exceeds a predetermined threshold value (also called a set value), thereby meeting the residual current protection requirements while allowing the load to continue to work at a minimum level to avoid unexpected secondary accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] These and / or other aspects, features and advantages of the present disclosure will become clearer and easier to understand through the following description of embodiments in conjunction with the accompanying drawings, in which:

[0016] Figure 1 is a diagram showing a system for residual current protection according to an embodiment of the present disclosure; and

[0017] Figure 2 is a diagram showing an exemplary application of a residual current circuit breaker according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0018] The present disclosure will be described in detail below with reference to exemplary embodiments of the present disclosure. However, the present disclosure is not limited to the embodiments described herein, and it can be implemented in many different forms. The described embodiments are only used to make the present disclosure thorough and complete, and to fully convey the concept of the present invention to those skilled in the art. The features of the various embodiments described can be combined or replaced with each other, unless explicitly excluded or should be excluded according to the context.

[0019] Unless otherwise defined, the technical terms or scientific terms used in this disclosure should be understood by people with ordinary skills in the field to which this disclosure belongs. The words "first", "second" and similar words used in this disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components.

[0020] As mentioned above, in some application scenarios of residual current circuit breakers, when the load suddenly stops working due to the power supply being cut off by the tripping action of the residual current circuit breaker, an unexpected secondary accident may occur. The following provides a residual current circuit breaker that can meet the residual current protection requirements while also meeting the minimum working requirements of the load to avoid unexpected secondary accidents, and a system including the residual current circuit breaker.

[0021] Figure 1 is a diagram showing a system for residual current protection according to an embodiment of the present disclosure. Figure 1 Figures (a), (b), (c) and (d) in the figure respectively show four different configurations of the residual current circuit breaker according to the embodiment of the present disclosure. The difference between them is that the backup power supply in figure (a) is located outside the residual current circuit breaker, the backup power supply in figure (b) is located inside the residual current circuit breaker as a part of the residual current circuit breaker, the backup power supply in figure (a) is replaced by a voltage converter in figure (c), and the backup power supply in figure (b) is replaced by a voltage converter in figure (d).

[0022] Illustrations (a), (b), (c) and (d) are described below respectively.

[0023] In diagram (a), a system 1 for residual current protection according to an embodiment of the present disclosure may include a residual current circuit breaker 10 , a power supply 11 , a load 12 and a backup power supply 13 .

[0024] The power supply 11 includes a grid power supply, a generator system, a solar power generation system, a wind power generation system, a battery system, a geothermal power generation system, and other energy sources or combinations thereof that can provide electrical energy to the load. The load 12 includes lighting equipment, monitoring equipment, alarm equipment, fire fighting equipment, medical equipment, and other electrical equipment that requires electrical energy to work, or combinations thereof. The backup power supply 13 includes a generator system, a solar power generation system, a wind power generation system, a battery system, a geothermal power generation system, and other energy sources or combinations thereof that can provide a voltage higher than the minimum value of the voltage required for the load 12 to work and lower than the maximum value of the safety voltage. The "safe voltage" here refers to a voltage range that complies with various national, regional, international or industry standards (for example, the National Standard of the People's Republic of China GB / T 3805-2008) and relevant laws and regulations that will not cause harm to the human or animal body even if it is touched by the human or animal body.

[0025] As shown in Figure (a), the current of the power supply 11 flows into the incoming terminal of the residual current circuit breaker 10 through the busbar, and then flows into the load 12 through the main circuit of the residual current circuit breaker 10. In this process, the residual current circuit breaker 10 can detect whether there is residual current in its main circuit and whether the residual current exceeds a predetermined threshold value I T (For example, its setting value). It is well known that the residual current circuit breaker has a residual current detection function. For example, the residual current circuit breaker may be arranged with a sensor or current transformer for measuring the phase current and the neutral current. The microcontroller unit (MCU) of the residual current circuit breaker can determine whether there is a residual current by detecting whether the vector sum of the phase current and the neutral current is zero, and further by comparing whether the difference between the phase current and the neutral current exceeds a predetermined threshold value I. T To determine whether a tripping action should be performed, this document does not need to describe in detail to avoid obscuring the present disclosure.

[0026] As shown in Figure (a), the residual current circuit breaker 10 may include a first switch T1, a second switch T2 and a control component 101. The first switch T1 is connected in series between the power supply 11 and the load 12. The second switch T2 is connected in series between the backup power supply 13 and the load 12. Since the backup power supply 13 is located outside the residual current circuit breaker 10, the residual current circuit breaker 10 may also include an external interface (not shown) for connecting to the backup power supply 13, and the second switch T2 is connected between the external interface and the load 12. The first switch T1 and the second switch T2 are mutually exclusive, that is, only one of them can be closed, which will be controlled by the control component 101 (as shown by the dotted line in the figure). The control component 101 responds to the residual current of the main circuit of the residual current circuit breaker 10 exceeding the predetermined threshold value I T, controls the first switch T1 to be opened and the second switch T2 to be closed. Otherwise, the control component 11 keeps the first switch T1 closed and the second switch T2 open. The control component 101 can be implemented in software, hardware, or a combination of software and hardware. The control component 101 can be a part of the MCU of the residual current circuit breaker 10, or it can be independent of the MCU.

[0027] When no residual current is detected or a residual current is detected but the residual current is less than a predetermined threshold value I T When the residual current is detected and the residual current is greater than the predetermined threshold value I T , the control component 101 can disconnect the first switch T1 (i.e., trip) and close the second switch T2, and the backup power supply 13 supplies power to the load 12. Since the voltage provided by the backup power supply 13 is higher than the minimum value of the voltage required for the load 12 to work and lower than the maximum value of the safety voltage, the load 12 can be maintained to continue working to a certain extent instead of completely stopping working. For example, in an instance where the load 12 is a lighting system, although switching from the power supply 11 to the backup power supply 13 may cause the lighting level of the lighting system to decrease, it will not cause a complete loss of lighting, which can especially reduce the occurrence of traffic accidents for outdoor lighting at night. For another example, in an instance where the load 12 is an electrical device with a wide-voltage power supply design, switching from the power supply 11 to the backup power supply 13 will not affect the normal operation of the electrical device.

[0028] In this way, the residual current circuit breaker 10 and the system 1 including the residual current circuit breaker 10 according to the embodiment of the present disclosure can meet the residual current protection requirements while also meeting the minimum working requirements of the load to avoid unexpected secondary accidents.

[0029] In diagram (b), the system 1 may include a residual current circuit breaker 10 according to an embodiment of the present disclosure, a power supply 11 and a load 12 .

[0030] The difference from the figure (a) is that the backup power supply 13 is arranged inside the residual current circuit breaker 10, that is, the residual current circuit breaker 10 includes a first switch T1, a second switch T2, a control component 101 and a backup power supply 102, and the second switch T2 is connected between the backup power supply 102 and the load 12. The backup power supply 102 can be a battery pack or other energy source or a combination thereof that can be arranged inside the residual current circuit breaker 10 and can provide a voltage higher than the minimum value of the voltage required for the operation of the load 12 and lower than the maximum value of the safety voltage. The other configurations are the same as those in the figure (a), and will not be repeated here to avoid repetition.

[0031] In diagram (c), the system 1 may include a residual current circuit breaker 10 according to an embodiment of the present disclosure, a power supply 11 , a load 12 , and a voltage converter 14 .

[0032] The difference from the figure (a) is that the backup power supply 13 is replaced by a voltage converter 14. The input end of the voltage converter 14 is connected to the incoming line end of the residual current circuit breaker 10 to convert the voltage of the power supply 11 into a voltage that is higher than the minimum value of the voltage required for the load 12 to work and lower than the maximum value of the safety voltage. Since the voltage converter 14 is located outside the residual current circuit breaker 10, the residual current circuit breaker 10 may also include an external interface (not shown) for connecting to the output end of the voltage converter 14, and the second switch T2 is connected between the external interface and the load 12. The other configurations are the same as those in the figure (a), and will not be repeated here to avoid repetition.

[0033] In diagram (d), the system 1 may include a residual current circuit breaker 10 according to an embodiment of the present disclosure, a power supply 11 and a load 12. That is, the residual current circuit breaker 10 includes a first switch T1, a second switch T2, a control component 101 and a voltage converter 103.

[0034] The difference from the figure (a) is that the backup power supply 13 is replaced by a voltage converter 103 and the voltage converter 103 is arranged inside the residual current circuit breaker 10. The input end of the voltage converter 103 is connected to the incoming line end of the residual current circuit breaker 10 to convert the voltage of the power supply 11 into a voltage higher than the minimum value of the voltage required for the load 12 to work and lower than the maximum value of the safety voltage. The second switch T2 is connected between the output end of the voltage converter 103 and the load 12. The other configurations are the same as those in the figure (a), and will not be repeated here to avoid repetition.

[0035] The four different configurations of the residual current circuit breaker 10 and the system 1 shown in Figures (a) to (d) can meet both the residual current protection requirements and the minimum load working requirements, and one of the four configurations can be selected according to the actual application scenario. For example, when the cost of the voltage converter is lower than the backup power supply, it will be more beneficial to select the residual current circuit breaker shown in Figure (c) or Figure (d).

[0036] In some examples, the voltage converter 14 shown in the diagram (c) or the voltage converter 103 shown in the diagram (d) may be designed to start performing a conversion operation of converting the voltage of the power supply 11 into a voltage higher than the minimum value of the voltage required for the load 12 to work and lower than the maximum value of the safety voltage once powered on. In other examples, the voltage converter 14 shown in the diagram (c) or the voltage converter 103 shown in the diagram (d) may be designed to start performing the conversion operation only when a trigger signal for triggering the conversion operation is received from the control component 101 or the MCU of the residual current circuit breaker 10. For example, the MCU of the residual current circuit breaker 10 may be programmed to start performing the conversion operation once it detects that the residual current exceeds a predetermined threshold value I T A trigger signal for triggering the voltage converter 14 or 103 to perform the conversion action is sent to the voltage converter 14 or 103. However, it is understandable that the residual current protection is generally urgent, and in order to disconnect the load 12 from the power supply 11 in time, it may be more advantageous to adopt a solution in which the voltage converter 14 or 103 starts to perform the conversion operation once it is powered on.

[0037] In some examples, a dual power supply switch (Automatic Transfer Switch, ATS) can be used to implement the first switch T1, the second switch T2 and the control component 101. For example, the switch body of the ATS can be used to implement the first switch T1 and the second switch T2, and the controller of the ATS can be used to implement the control component 101. When the MCU of the residual current circuit breaker detects that the residual current exceeds the predetermined threshold value I T When the residual current circuit breaker 10 is switched, a trigger signal for triggering the ATS to perform a switching operation can be sent to the controller of the ATS. This makes the residual current circuit breaker 10 easy to implement.

[0038] In some instances, the first switch T1 and the second switch T2 can be implemented using a solid-state switch (also known as a contactless switch). Solid-state switches have the advantages of fast response speed, low power consumption, and long life, which is beneficial for application scenarios that require a low time interval between the disconnection of the first switch T1 and the closure of the second switch T2. For example, in an application scenario where the load 12 is a monitoring system, in order to avoid missing critical, instantaneous monitoring information, it may be required that the monitoring is not interrupted as much as possible. If the time interval from the disconnection of the first switch T1 to the closure of the second switch T2 is too long (for example, hundreds or thousands of microseconds), critical monitoring information may be missed. When the first switch T1 and the second switch T2 are implemented using a solid-state switch, the time interval can be as low as a few microseconds, thereby avoiding missing critical monitoring information.

[0039] In some examples, the residual current circuit breaker 10 further includes a storage component and a communication component. The storage component can store information related to the detected residual current, information related to the switching of the first switch T1 and the second switch T2, etc. The communication component can send the information stored in the storage component to an external device. The external device can be, for example, a computing device of a maintenance personnel. The maintenance personnel will use this information to analyze the cause of the residual current and then eliminate this cause. Generally, after eliminating this cause, the second switch T2 is disconnected and the first switch T1 is closed by manual closing to restore the power supply of the power supply 11 to the load.

[0040] Further, for ease of understanding, the following Figure 2 The lighting system is used as an example to illustrate the application of the residual current circuit breaker 10. However, it should be understood that the use cases of the residual current circuit breaker 10 are not limited thereto, and there may be more use cases, such as the monitoring system mentioned above, which need not be exhaustively listed in this disclosure.

[0041] Figure 2 is a diagram showing an exemplary application of a residual current circuit breaker according to an embodiment of the present disclosure.

[0042] Reference Figure 2 , wherein the residual current circuit breaker 10 is taken as an example of the configuration shown in Figure (d), but is not limited thereto, and the configurations shown in Figures (a) to (c) may also be used.

[0043] As shown, the load 12 includes a plurality of illuminators (such as LED street lamps) and a plurality of drivers (such as LED drivers) for driving each of the plurality of illuminators. Each of the plurality of drivers detects that its supply voltage is lower than a predetermined voltage threshold V T When the corresponding lighting device is provided with driving power that enables the lighting device to illuminate at the minimum illumination, the predetermined voltage threshold V T It may be the highest value of the voltage provided by the voltage converter 103 (or the voltage converter 14 or the backup power source 13 or 102).

[0044] against Figure 2 For example, when no residual current is detected or a residual current is detected but the residual current is less than a predetermined threshold value I T When the residual current is detected and the residual current is greater than the predetermined threshold value I TWhen the control component 101 controls the first switch T1 to be opened and the second switch T2 to be closed. The voltage converter 103 supplies power to multiple LED street lamps. For example, the voltage converter 103 converts the voltage 220Vac of the power supply 11 into 50Vac. When each driver detects that the power supply voltage is lower than 50Vac (including 50Vac and below), it provides the corresponding LED street lamp with a driving power that can illuminate it with the lowest illumination. For example, the driving power provided can be 1 / 10, 1 / 5 or other proportions of its rated power. In this way, although the illumination of the LED street lamp decreases, it will not completely lose illumination. For example, in the case of outdoor lighting at night, it can effectively avoid traffic accidents caused by pedestrians, animals or vehicles being completely invisible.

[0045] The foregoing describes a residual current circuit breaker according to an embodiment of the present disclosure, which is easy to manufacture, easy to implement, and low in cost. In addition to providing the functions provided by a traditional residual current circuit breaker, it can also maintain the load to continue working to a certain extent after tripping, thereby avoiding unexpected secondary accidents.

[0046] The block diagrams involved in the present disclosure are not intended to require or imply that the connections and arrangements must be made in the manner shown in the block diagrams. Those skilled in the art should understand that the above-mentioned specific embodiments are only examples and not limitations, and various modifications, combinations, partial combinations and replacements can be made to the embodiments of the present invention according to design requirements and other factors, as long as they are within the scope of the attached claims or their equivalents, they belong to the scope of rights to be protected by the present disclosure.

Claims

1. A residual current circuit breaker, comprising: A first switch, connected in series between the power supply of the residual current circuit breaker and the load; A second switch is connected in series between the backup power supply and the load; as well as a control component, in response to the residual current of the main circuit of the residual current circuit breaker exceeding a predetermined threshold, controlling the first switch to be turned off and the second switch to be turned on, The voltage of the backup power supply is higher than the minimum value of the voltage required for the load to work and lower than the maximum value of the safety voltage, and The first switch and the second switch are mutually exclusive.

2. The residual current circuit breaker according to claim 1, wherein the backup power supply is located outside the residual current circuit breaker, and the residual current circuit breaker further comprises: external interface for connecting to the backup power supply, and Wherein, the second switch is connected between the external interface and the load.

3. The residual current circuit breaker according to claim 1, wherein: The backup power supply is located inside the residual current circuit breaker as a part thereof.

4. The residual current circuit breaker according to claim 2 or 3, wherein: The backup power supply is provided by a voltage converter, the input end of which is connected to the incoming line end of the residual current circuit breaker to convert the voltage of the power supply into a voltage higher than the minimum value of the voltage required for the load to work and lower than the maximum value of the safety voltage, and The second switch is connected between the output terminal of the voltage converter and the load.

5. The residual current circuit breaker according to claim 4, wherein: The voltage converter performs the conversion in response to receiving a trigger signal for triggering it to perform the conversion.

6. The residual current circuit breaker according to claim 1, wherein: The first switch, the second switch and the control component are provided by a dual power supply switching switch.

7. The residual current circuit breaker according to claim 1, wherein: The first switch and the second switch are solid-state switches.

8. A system for residual current protection, comprising: Power supply; load; as well as A residual current circuit breaker according to any one of claims 1 to 7.

9. The system according to claim 8, wherein: The load includes a plurality of lighting devices and a plurality of drivers respectively used to drive each of the plurality of lighting devices.

10. The system according to claim 9, wherein: Each of the plurality of drivers provides driving power to a corresponding lighting device that enables the lighting device to illuminate at a minimum illumination level when detecting that the power supply voltage thereof is lower than a predetermined voltage threshold, wherein the predetermined voltage threshold is a maximum value of the voltage of the backup power supply.

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