Method of identifying a short-like event within a circuit breaker

Abstract

A method of identifying a near-short event in a circuit breaker is described. The method includes sampling an input current to the circuit breaker to determine a maximum value of a slope of a curve of the input current. The method further includes determining that the input current has reached a predetermined, pre-set, selected or calculated short circuit threshold TH SC before, again sampling the input current. The method involves determining from the sampled input current that a slope value of the input current has changed from a maximum slope value to a lower slope value, thereby determining that the input current indicates a near-short event, rather than a true short circuit event.

Description

Technical Field

[0001] This invention specifically relates to a method for identifying or detecting short-circuit (SC) events in a circuit breaker (CB). More specifically, this invention relates to a digital real-time algorithm for identifying and passing SC-like events within microseconds to prevent erroneous triggering of the CB. Background Technology

[0002] Incorrect triggering of the current flow (CB) is a common problem during the startup of devices with capacitive or inductive loads, for example. A "short-circuit-like" inrush current can occur during the startup of loads such as capacitive ones. This is a particularly serious problem in direct current (DC) power grids.

[0003] Furthermore, once a circuit breaker (CB) is installed, its protection rating is generally not changeable or adjustable. Typically, unless the CB is reinstalled, its electrical parameters, such as rated current and trip curve, cannot be altered arbitrarily.

[0004] Therefore, what is needed more than other things is an improved method for identifying or detecting short-circuit events within a CB and for responding to such events. Summary of the Invention

[0005] In a first key aspect, the present invention provides a method for identifying SC events within a CB (Circuit Breaker). The method includes sampling an input current to the circuit breaker to determine the maximum slope of a curve of the input current. The method further includes sampling the input current when it reaches a predetermined, preset, selected, or calculated SC threshold TH. SC Previously, the input current was sampled again. This method involves determining, from the sampled input current, that the slope value of the input current changes from the maximum slope value to a lower slope value, thereby determining that the input current indicates a SC-like event rather than a true SC event.

[0006] Preferably, the step of determining that the input current indicates the SC-like event includes: determining from the sampled input current that the slope value of the input current has changed from the maximum slope value to a slope value lower than the expected slope value. Also preferably, the step of determining that the input current indicates the SC-like event includes: determining from the sampled input current that the slope value of the input current has changed from the maximum slope value to a slope value lower than the expected slope value of the actual SC event.

[0007] The present invention preferably includes a solid-state CB with real-time fault identification functionality performed by a digital controller to distinguish between SC current and SC-like inrush current in, for example, a low-voltage direct current (LVDC) grid. The fault identification function prevents or at least reduces erroneous triggering of the CB during capacitive / inductive load startup, while maintaining timely protection in the event of a genuine short circuit.

[0008] Furthermore, the CB configuration should ideally be highly flexible, allowing for dynamic changes to CB settings based on load conditions. This enables dynamic reconfiguration of the CB without requiring reinstallation and / or physical modifications.

[0009] Preferably, the CB includes a digital DC CB that executes a digital real-time algorithm to identify and pass identified SC-like events within microseconds to avoid erroneous triggering of the CB. This algorithm preferably requires real-time current data. The invention is also applicable to AC power grids.

[0010] The CB can be configured with a user interface and / or display for local access to the CB's controller, enabling users to manually configure or reconfigure the CB's operating parameters, such as current ratings and one or more trip curves.

[0011] CB is best configured for LVDC grids, such as battery storage systems, data centers, electronic mobile applications, solar photovoltaic applications, and DC or AC grids for buildings.

[0012] In a second principal aspect, the invention provides a controller for a CB, the controller including memory storing machine-readable instructions and a processor for executing the machine-readable instructions, such that when the processor executes the machine-readable instructions, it causes the controller to implement the steps of the first principal aspect of the invention.

[0013] In a third principal aspect, the present invention provides a CB having a controller according to a second principal aspect of the invention.

[0014] In a fourth principal aspect, the present invention provides a non-transitory computer-readable medium storing machine-readable instructions, wherein, when executed by a processor or controller, the machine-readable instructions configure the processor or controller to implement the steps of the first principal aspect of the invention.

[0015] The objective of this invention is to mitigate or eliminate, to some extent, one or more problems associated with known methods for identifying or detecting SC-like events in a CB.

[0016] The above objectives are achieved through a combination of features in the main claims; the sub-claims disclose further preferred embodiments of the invention.

[0017] Another objective of the present invention is to mitigate or eliminate, to some extent, one or more problems associated with known methods of responding to SC-like events within a CB.

[0018] Another objective of the present invention is to provide a controller for CB that is configured to identify and pass SC-like events within microseconds to avoid erroneous triggering of CB.

[0019] Another objective of this invention is to provide a digital real-time algorithm to identify and process SC-like events within microseconds to avoid erroneous triggering of CB.

[0020] Another objective of this invention is to enable the CB to be dynamically reconfigured without requiring reinstallation and / or physical modification of the CB.

[0021] Those skilled in the art will be able to deduce other objectives of the invention from the following description. Therefore, the above statement of objectives is not exhaustive, but merely illustrative of a portion of the many objectives of the invention.

[0022] An abstract of an invention may not necessarily reveal all the features necessary to define the invention; the invention may exist in sub-combinations of the disclosed features.

[0023] The features of the invention have been broadly outlined above to better understand the detailed description thereof below. Other features and advantages of the invention will be described below, forming the subject matter of the claims. For those skilled in the art, the concepts and specific embodiments can readily be used as the basis for modifications or the design of other structures to achieve the same objectives of the invention. Attached Figure Description

[0024] The above and further features of the invention will become apparent from the following description of preferred embodiments, which are associated with the accompanying drawings by way of example only, wherein:

[0025] Figure 1 A schematic block diagram including a circuit breaker according to the present invention;

[0026] Figure 2 This is a diagram illustrating the principle of the present invention;

[0027] Figure 3 yes Figure 2 Enlarged portions of the figures in the diagram are provided to better illustrate the principles of the invention; and

[0028] Figure 4 This is a flowchart of a preferred method according to the present invention. Detailed Implementation

[0029] The following description illustrates preferred embodiments by way of example only and is not limited to combinations of features necessary for carrying out the invention.

[0030] In this specification, references to "an embodiment" or "one embodiment" mean that a particular feature, structure, or characteristic described in connection with that embodiment is included in at least one embodiment of the invention. The phrase "in one embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a single or alternative embodiment mutually exclusive with other embodiments. Furthermore, various features that may be present in some embodiments but not in others are described. Similarly, various requirements are described that may be requirements of some embodiments but not others.

[0031] It should be understood that the components shown in the figures can be implemented in various forms of hardware, software, or combinations thereof. These components can be implemented in a combination of hardware and software on one or more appropriately programmed general-purpose devices, which may include processors, memory, and input / output interfaces. This specification illustrates the principles of the invention. Therefore, it should be understood that those skilled in the art will be able to design various arrangements, although not expressly described or shown herein, which embody the principles of the invention and are included within its spirit and scope.

[0032] Furthermore, all statements herein referencing the principles, aspects, and embodiments of the invention, as well as specific examples thereof, are intended to cover their structural and functional equivalents. Moreover, such equivalents are intended to include both currently known equivalents and those developed in the future, i.e., any components developed that perform the same function, regardless of their structure.

[0033] Therefore, for example, those skilled in the art will understand that the block diagrams presented herein represent conceptual views of systems and devices embodying the principles of the present invention.

[0034] The functionality of the various components shown in the figure can be provided using dedicated hardware and hardware capable of executing software associated with appropriate software. When provided by a processor, functionality can be provided by a single dedicated processor, a single shared processor, or multiple separate processors, some of which may be shared. Furthermore, the explicit use of the terms "processor" or "controller" should not be construed as referring specifically to hardware capable of executing software, and may imply, but is not limited to, digital signal processor ("DSP") hardware, read-only memory ("ROM") for storing software, random access memory ("RAM"), and non-volatile memory.

[0035] In its claims, any component referred to as a means for performing the specified function is intended to cover any manner in which the function is performed, including, for example, a) a combination of circuit components performing the function or b) any form of software, thus including firmware, microcode, etc., combined with appropriate circuitry for performing the software to perform the function. The invention as defined by these claims lies in the combination and arrangement of the functions provided by the various said means in the manner claimed in the claims. Therefore, any means that can provide these functions are considered equivalent to those shown herein.

[0036] refer to Figure 1 CB 10 includes a digital controller 12, but any controller suitable for implementing the method according to the invention described below can be used in CB 10. CB 10 includes at least one switch 14 that receives incoming current from a power-in input port 15. Switch 14 is connected to a current sensing circuit 16 that receives the input current at the power-in input port 15 and measures parameters of the input current. The current sensing circuit 16 inputs the input current to switch 14, which in turn inputs the current to a load connected to a power-out port 17. The current sensing circuit 16 communicates the measured parameters of the input current to at least one processor 18 of the digital controller 12. The digital controller includes at least one memory 20. The memory stores machine-readable instructions that, when executed by the processor 18, enable the digital controller 12 to perform various CB functions, including the method according to the invention described below. The digital controller 12 can implement various CB functions by executing one or more digital real-time algorithms. Digital controller 12 may also include control circuitry 22, which is controlled by processor 18, upon recognition or detection of an SC event (i.e., a rapid increase in input current exceeding a predetermined, preset, selected, or calculated SC threshold TH of CB 10). SC When the above occurs, the drive switch 14 isolates CB 10 from the input current, i.e., trips or breaks the circuit. Either the current detection circuit 16 or the control circuit 22 can include a function block of the processor 18, which is implemented by executing machine-readable instructions.

[0037] Understandably, CB 10 may include multiple power-on input ports 15 and multiple power-off output ports 17, as well as their respective switches 14 and current detection circuits 16.

[0038] In some embodiments, CB 10 may include a user interface and / or display 24 for enabling a user to locally access digital controller 12 to manually configure or reconfigure operating parameters of CB 10, such as current ratings and one or more trip curves.

[0039] In some embodiments, CB 10 may include a communication interface 25 to enable the configuration or reconfiguration of operating parameters of CB 10 from an external device (such as a wireless communication device, a computer, or a similar device). Communication interface 25 may include a wireless communication interface and / or a physical communication interface. CB 10, the wireless communication device, or the computer or similar device may include Internet of Things (IoT) supported devices.

[0040] The operating parameters of CB 10 can be dynamically configured or reconfigured according to the load. This allows CB 10 to be configured and reconfigured without reinstallation and / or physical modification of CB 10.

[0041] Understandable Figure 1 The structure of the CB 10 shown is an example of a CB 10 in which the method of the present invention can be implemented, but the method of the present invention can be implemented in any suitable CB with other structural configurations, as long as the CB includes a controller having at least one processor and at least one memory.

[0042] CB 10 may include a solid-state CB equipped with a real-time fault identification function performed by digital controller 12 to distinguish between SC current (SC event) and SC-like inrush current (SC event), for example, in an LVDC grid. The fault identification function can prevent or at least reduce false tripping of CB 10 during load startup. This prevents or at least reduces false triggering or tripping of CB 10 during capacitive / inductive load startup, while maintaining timely protection in the event of a genuine SC event. However, CB 10 is capable of identifying SC-like events caused by any circumstances where inrush current or similar current is received by power-on input port 15, including, for example, when a device is connected or plugged into a power source.

[0043] The CB 10 effectively implements real-time fault identification, using at least one digital real-time algorithm to identify and process identified SC-like events within microseconds, thus preventing erroneous triggering or tripping of the CB 10. This algorithm is best implemented using real-time current data.

[0044] Although CB 10 is described as a DC device in this document, it is understood that CB 10 can also be adapted to operate in an AC power grid.

[0045] CB is preferably configured for use in LVDC (low-voltage direct current) grids, such as battery storage systems, data centers, electronic mobile applications, solar photovoltaic applications, and DC or AC grids for buildings.

[0046] Figure 2 It is a diagram illustrating the principle of the invention, and Figure 3 Provided Figure 2 The enlarged portion of the diagram is shown to better explain the principles of the invention.

[0047] refer to Figure 2 It displays two current curves. The first curve 30 contains or indicates a real SC event, namely, the SC current detected by the current detection circuit 16, which rapidly rises to the SC threshold TH of CB 10. SC That's all. In this example, the SC threshold TH of CB 10... SC It's set to 100 amps, but this is just an example. Figure 2 A second current curve 32 is also shown, including or indicating a SC-like event, i.e., a SC-like current is detected by the current detection circuit 16, wherein the SC-like current rapidly rises to and subsequently exceeds the SC threshold TH of the CB 10. SC In a traditional circuit breaker (CB), both SC events and SC-like events trigger switch 14 in CB 10, disconnecting the circuit between the power-on input port 15 and the power-off output port 17. However, in the case of the current curve 32 corresponding to a SC-like event, this will cause CB 10 to trigger incorrectly, such as... Figure 2 As shown, the current curve 32 of a SC-like event typically drops rapidly to the normal operating level within a few microseconds.

[0048] The method of the present invention includes continuously or periodically sampling the input current received at the power-on input port 15, preferably detecting or determining the maximum slope of the current curves 30, 32 of the input current once the current exceeds a minimum current threshold THcc. Figure 2 and Figure 3 Only two sampling points, 34 and 36, are shown, but it is understood that in practice there may be multiple (n) such sampling points. Sampling will continue at least until it is determined that the input current indicates a genuine SC event, in which case switch 14 will be triggered; or until it is determined that the input current indicates a SC-like event, and therefore switch 14 will not be triggered. If it is determined that the input current indicates a SC-like event, it is preferable to continue sampling the input current until the input current at least returns to a normal operating level.

[0049] According to the present invention, a method for identifying SC-like events in CB 10 includes sampling the input current to determine whether the input current reaches the SC threshold TH. SC The maximum slope of the previous input current curves 30 and 32. Figure 2 The first sampling point 34 in the diagram illustrates this point, with its current slope sampled as the maximum value I. slope_maxIt is understandable that continuously or periodically sampling the input current can determine when the input current reaches the SC threshold TH. SC The maximum slope value of the input current curves 30 and 32 at any previous point. In other words, the digital controller 12 continuously or periodically calculates the slope of the input current curves 30 and 32 and updates the maximum slope value I of the current curves 30 and 32 as necessary. slope_max This method involves resampling the input current at least once, but preferably when the input current level reaches the SC threshold TH of CB 10. SC The input current is sampled multiple times, either continuously or periodically, over a previous period. This method involves determining from the sampled input current whether the slope value of the input current deviates from its maximum slope value I. slope_max To become a lower slope value ( slope_max To determine whether the input current indicates an event of class SC.

[0050] In some embodiments, this may include determining from the sampled input current whether the slope value of the input current has decreased from its maximum slope value I. slope_max The slope value became lower than expected. slope_max ).

[0051] In other embodiments, this may include determining from the sampled input current whether the slope value of the input current has decreased from its maximum slope value I. slope_max The slope value becomes lower than the expected slope value of the actual SC event. slope_max The slope value of the input current of a real SC event can be determined from empirical data, can be calculated in real time by the digital controller 12, can be stored in the memory 20 of the digital controller 12 as a lookup table, or can be determined from the trip curve of the digital controller 12 preloaded into the CB 10.

[0052] exist Figure 2 It is not immediately apparent that when the input current level reaches the SC threshold TH... SC Previously, the slope of the current curve 32 for SC-like events changed compared to curve 30 for SC events. However, Figure 3 Provided a magnified section Figure 2 It can be seen that when the input current level reaches the SC threshold TH SC For a period of time, the slope of the current curve 32 for SC-like events was indeed significantly reduced compared to the current curve 30 for SC events. Therefore, the slope value of the current curve can be used as a judgment parameter for the true SC events of CB 10.

[0053] It should be noted that, in Figure 2 and Figure 3 ​​​In the middle, the slope 36 of the current curve 32 of the subsequently sampled SC-like event will be the same as the maximum slope value I. slope_max Compared to I slope_max The current slope factor M can be modified from a pre-defined, preset, selected, or calculated value. If the slope of subsequently sampled current curves 30 and 32 is less than M multiplied by the maximum slope value I... slope_max If so, the input current is determined to be an indicator-type SC event. The current slope factor M is less than 1. The current slope factor M effectively includes a degree or amount such that subsequent sampled values ​​of the slope of the input current curves 30 and 32 must be less than the maximum slope value I. slope_max Multiply by this degree or amount to determine whether the input current contains or indicates a SC-like event, rather than a true SC event. The current slope factor M is preferably adjustable. This allows for fine-tuning of CB 10 to more accurately distinguish between SC-like events and true SC events.

[0054] The provided method preferably includes the following steps: achieving an SC threshold TH at the input current level. SC Previously, it was determined that the input current indicated a SC-like event, and the SC threshold TH was set. SC Raise to temporary SC threshold TH* SC Set the SC threshold TH SC Increase to a higher temporary SC threshold TH* SC This is to prevent or reduce the processing of SC-like events as real SC events, thereby preventing or reducing erroneous triggering of CB10. Figure 2 and Figure 3 In the example, the temporary SC threshold TH* SC The current is increased to 400 amps, but other increases can be applied, as long as these values ​​are sufficient or determined to prevent the determined SC-type event from triggering CB 10.

[0055] The method may also include setting the SC threshold TH SC Increase to a higher temporary SC threshold TH* SC The event is allowed to continue for a set period of time, or for a period of time, which is sufficient to prevent the identified SC-type event from triggering CB 10.

[0056] SC threshold TH SC and / or temporary SC threshold TH* SC It can be adjusted manually or dynamically.

[0057] This method may include setting a temporary SC threshold TH* SC Reset to its previous SC threshold level TH SCAlternatively, it may be reset to a new SC threshold level once it is determined that the identified SC-like event has ended and / or the aforementioned period has expired. However, the method preferably includes resetting the threshold level once it is determined that the input current value is equal to or less than the minimum current threshold TH. CC The temporary SC threshold TH* SC Reset to its previous threshold level TH SC Alternatively, it can be reset to a new SC threshold level.

[0058] Before sampling the input current to determine the maximum slope of the input current curves 30 and 32, it is best to first compare the input current with the minimum current threshold TH. CC A comparison is made. If a certain value of the input current is equal to or less than the minimum current threshold TH... CC If the input current is not sampled, the method returns to the step of sampling the input current.

[0059] In some embodiments, the memory 20 of the digital controller 12 is preloaded with one or more standard or conventional CB trip curves. The one or more standard or conventional CB trip curves may include type B, type C, type D and / or type Z trip curves.

[0060] In some embodiments, the expected slope value of a real SC event can be determined from one or more standard or conventional CB trip curves preloaded into memory 18.

[0061] Figure 4 A more complete flowchart of the method 100 according to the present invention is provided. Method 100 begins at start 105. In the next step 110, the input current received at the power-on input port 15 of CB 10 is continuously or periodically sampled by the current detection circuit 16. In decision block 115, the digital controller 12 determines whether the sampled current I(n) is greater than the minimum current threshold TH. CC If the sampled current I(n) is determined to be less than or equal to the minimum current threshold TH CC Method 100 returns to step 110, which involves sampling the input current I. However, if the SC threshold TH... SC Previously raised to the temporary SC threshold TH* SC Therefore, in step 120, before method 100 returns to step 110 of sampling the input current I, the temporary SC threshold TH* is... SC Reset to the previous SC threshold TH SC Or a new SC threshold TH SCBefore step 120, method 100 may include a decision box 118, in which it determines whether a flag (e.g., the number of resets) is set to 0. If the flag (e.g., the number of resets) is not set to 0, then method 100 returns to step 110 without including step 120. Conversely, method 100 returns to step 110 via step 120, and the flag (number of resets) is set to 1.

[0062] However, if the digital controller 12 determines at decision block 115 that the sampled current I(n) is greater than the minimum current threshold TH CC Then method 100 continues to decision box 125.

[0063] At decision box 125, digital controller 12 determines whether the sampled current I(n) is greater than the SC threshold TH. SC If the sampled current I(n) is determined to be less than or equal to the SC threshold TH SC Method 100 continues to decision box 130, where digital controller 12 determines whether the input current received at power-on input port 15 of CB 10 includes or indicates a Class SC event. Digital controller 12 makes this determination based on the sampled slope of input current I, as described above. If at decision box 130, digital controller 12 determines that input current I does not yet include or indicate a Class SC event, then method 100 returns to step 110, which samples input current I. If digital controller 12 determines that input current I does indeed include or indicate a Class SC event, method 100 continues to step 135, where digital controller 12 sets the SC threshold TH. SC Set as temporary SC threshold TH* SC .

[0064] After step 135, the digital controller 12 located in decision box 140 determines whether the sampled current I(n) is greater than the temporary SC threshold TH*. SC (the elevated value). If the sampled current I(n) is less than or equal to the temporary SC threshold TH* SC Then method 100 returns to step 110, which samples the input current I. However, if in decision box 140, the sampled current I(n) is determined to be greater than the temporary SC threshold TH*. SC Method 100 continues to step 145, where the digital controller 12 recognizes that an SC event has occurred and the input current I is greater than the temporary SC threshold TH*. SC In step 150, the CB 10 operation switch 14 is triggered, disconnecting the circuit between the power-on input port 15 and the power-off output port 17. After the digital controller 12 determines that an SC event has occurred to trigger the CB 10, method 100 ends at step 155.

[0065] Returning to decision box 125, if it is determined that the sampled current I(n) is greater than the SC threshold TH SC Method 100 continues with steps 145, 150, and 155.

[0066] CB 10 may include a thermal trip protection circuit as a functional module of digital controller 12, such that method 100 includes step 160, which performs a thermal trip on CB 10 when digital controller 12 identifies an event of a thermal protection problem.

[0067] The aforementioned device can be implemented, at least partially, in software. Those skilled in the art will understand that it can be implemented, at least partially, using general-purpose computer equipment or custom-made equipment.

[0068] Here, the various aspects of the methods and apparatus described herein can be executed on any device constituting a communication system. The programmatic aspects of this technology can be considered as a “product” or “manufactured product,” typically existing or contained in a machine-readable medium in the form of executable code and / or associated data. “Storage” media include any or all memory, or related modules thereof, of mobile stations, computers, processors, or similar devices, such as various semiconductor memories, tape drives, disk drives, etc., readily available for software programming. All or part of the software can sometimes be communicated via the Internet or various other telecommunications networks. For example, such communication allows software to be loaded from one computer or processor to another. Therefore, another medium that may carry software elements includes optical, electrical, and electromagnetic waves, used, for example, through physical interfaces between local devices, through wired and optical fixed-line networks, and various air links. Physical components carrying such waves, such as wired or wireless links, optical links, or the like, can also be considered as media carrying software. Here, unless limited to tangible, non-temporary “storage” media, terms such as “computer or machine-readable medium” refer to any medium involved in providing execution instructions to a processor.

[0069] While the invention has been detailed and described in the drawings and foregoing description, it should be considered illustrative and not restrictive in nature. It is to be understood that only exemplary embodiments have been shown and described, and the scope of the invention is not limited in any way. It is understood that any functionality described herein can be used in any embodiment. The illustrative embodiments are not mutually exclusive, nor do they exclude other embodiments not listed herein. Accordingly, the invention also provides embodiments comprising combinations of one or more of the illustrative embodiments described above. Modifications and changes can be made to the invention without departing from its spirit and scope; therefore, only the limitations set forth in the appended claims should be imposed.

[0070] In the following claims and the preceding description of the invention, unless the context requires otherwise due to the language of expression or necessary meaning, variations of the words “comprising” or “including” are used in the sense of inclusion, that is, indicating the presence of the stated feature but not excluding the presence or addition of further features in the various embodiments of the invention.

[0071] It should be understood that if any prior art publication is mentioned in this document, such mention does not constitute an admission that the publication constitutes part of the general knowledge in the art.

Claims

1. A method for identifying short-circuit-like SC events in a circuit breaker CB, characterized in that, The method includes: The input current to the circuit breaker is sampled to determine the maximum slope value of the curve of the input current; When the input current reaches a predetermined, preset, selected, or calculated SC threshold TH SC Previously, the input current was sampled again; and Based on the sampled input current, it is determined that the slope value of the input current changes from the maximum slope value to a lower slope value, thereby determining that the input current indicates a SC-like event rather than a true SC event, wherein the magnitude of the input current reaches a predetermined, preset, selected, or calculated SC threshold TH. SC Previously, it was determined that the input current indicated the SC-type event, and the SC threshold TH was set. SC Raise to temporary SC threshold TH* SC .

2. The method according to claim 1, characterized in that, The step of determining that the input current indicates the type SC event includes: determining from the sampled input current that the slope value of the input current has changed from the maximum slope value to a slope value lower than the expected slope value of the actual SC event.

3. The method according to claim 1, characterized in that, The current slope factor M is predetermined, preset, selected, or calculated. If a subsequent sampled value of the slope of the curve of the input current is less than M multiplied by the maximum slope value, the input current is determined to be an indication of the SC-type event, wherein the current slope factor M is less than 1.

4. The method according to claim 3, characterized in that, The maximum slope value of the curve of the input current is determined to include: upon reaching the SC threshold TH SC The maximum slope I at any point on the previously mentioned input current curve slope_max .

5. The method according to claim 1, characterized in that, The temporary SC threshold TH* that is raised is among them. SC Increased to a predetermined, preset, selected, or calculated size TH* SC It is determined to be sufficient to prevent the determined SC-type event from triggering the CB.

6. The method according to claim 1, characterized in that, The temporary SC threshold TH* that is raised is among them. SC The boost is raised to a predetermined, preset, selected, or calculated size, which is determined to be sufficient for a period of time to prevent the determined SC-type event from triggering the CB.

7. The method according to claim 1, characterized in that, When the input current is determined to be equal to or less than the minimum current threshold TH CC When, the temporary SC threshold TH* SC The SC threshold TH is reset to its previous value. SC Alternatively, it may be reset to a new SC threshold.

8. The method according to claim 1, characterized in that, When the determined SC-type event has ended and / or when a period of time has expired, the temporary SC threshold TH* SC The SC threshold TH is reset to its previous value. SC Alternatively, it may be reset to a new SC threshold.

9. The method according to claim 1, characterized in that, Wherein the slope factor M, the SC threshold TH SC And / or the temporary SC threshold TH* SC Any one of them is adjustable.

10. The method according to claim 1, characterized in that, Before sampling the input current to determine the maximum slope value of the curve of the input current, the input current is compared with a minimum current threshold TH. CC , If the value of the input current is equal to or less than the minimum current threshold TH CC Then the method returns to the step of sampling the input current.

11. The method according to claim 1, characterized in that, The CB has a controller containing memory, and the method includes preloading one or more standard or conventional CB trip curves into the memory of the controller.

12. The method according to claim 11, characterized in that, The one or more standard or conventional CB trip curves mentioned above include B, C, D and / or Z type trip curves.

13. The method according to claim 11, characterized in that, The slope value expected for a real SC event is determined by one or more standard or conventional CB trip curves preloaded into the memory of the controller of the CB.

14. The method according to claim 11, characterized in that, One or more electrical parameters of the CB are loaded into the memory of the controller.

15. The method according to claim 14, characterized in that, The one or more electrical parameters mentioned therein are loaded into the memory by any one or more of the following: The user interface of the CB; Wireless devices that communicate wirelessly with the CB; and / or An external computer that communicates with the CB.

16. A controller for a circuit breaker (CB), the controller including a memory storing machine-readable instructions and a processor executing the machine-readable instructions, wherein when the processor executes the machine-readable instructions, it configures the controller to perform the following steps: The input current to the circuit breaker is sampled to determine the maximum slope value of the curve of the input current; When the input current reaches a predetermined, preset, selected, or calculated SC threshold TH SC Previously, the input current was sampled again; and Based on the sampled input current, it is determined that the slope value of the input current changes from the maximum slope value to a lower slope value, thereby determining that the input current indicates a SC-like event rather than a true SC event. When the magnitude of the input current reaches the predetermined, preset, selected, or calculated SC threshold TH SC Previously, it was determined that the input current indicated the SC-type event, and the SC threshold TH was set. SC Raise to temporary SC threshold TH* SC .

17. A circuit breaker (CB) with a controller, the controller including a memory storing machine-readable instructions and a processor for executing the machine-readable instructions, wherein when the processor executes the machine-readable instructions, it configures the controller to perform the following steps: The input current to the circuit breaker is sampled to determine the maximum slope value of the curve of the input current; When the input current reaches a predetermined, preset, selected, or calculated SC threshold TH SC Previously, the input current was sampled again; and Based on the sampled input current, it is determined that the slope value of the input current changes from the maximum slope value to a lower slope value, thereby determining that the input current indicates a SC-like event rather than a true SC event. When the magnitude of the input current reaches the predetermined, preset, selected, or calculated SC threshold TH SC Previously, it was determined that the input current indicated the SC-type event, and the SC threshold TH was set. SC Raise to temporary SC threshold TH* SC .

Images