Systems and methods for case suppression for overcurrent protection

Abstract

Comprising a plurality of power supply units, a processor, and a non-transitory computer-readable medium storing instructions thereon, the instructions, when used by the processor, cause a set of functions to be executed. The set of functions includes detecting an overcurrent of a first power supply unit among the plurality of power supply units. The set of functions includes determining that the overcurrent of the first power supply unit corresponds to current sharing among the plurality of power supply units. The set of functions includes suppressing an overcurrent protection mode of the first power supply in response to determining that the overcurrent of the first power corresponds to current sharing.

Description

Background Art

[0001] When two or more power supply units are connected in parallel for current sharing, the total power output capacity of the system increases, and the load capacity correspondingly increases. However, during the startup phase of current sharing, each power supply unit may encounter a load that triggers overcurrent protection. In this case, the overcurrent protection will prevent the power supply unit from outputting the required power to supply the load. Summary of the Invention

[0002] The present disclosure relates to systems and methods for suppressing the undesired triggering of overcurrent protection in a power supply unit. Specifically, examples describe suppressing the undesired triggering of overcurrent protection based on determining that two or more power supply units are current sharing.

[0003] In one aspect, a system is described. The system includes a plurality of power supply units, a processor, and a non-transitory computer-readable medium storing instructions that, when used by the processor, cause a set of functions to be performed. The set of functions includes detecting an overcurrent of a first power supply unit among the plurality of power supply units. The set of functions includes determining that the overcurrent of the first power supply unit corresponds to current sharing among the plurality of power supply units. The set of functions includes suppressing the overcurrent protection mode of the first power supply in response to determining that the overcurrent of the first power corresponds to current sharing.

[0004] In a second aspect, a method is described. The method includes detecting an overcurrent of a first power supply unit among a plurality of power supply units. The method includes determining that the overcurrent of the first power supply unit corresponds to current sharing among the plurality of power supply units. The method includes suppressing the overcurrent protection mode of the first power supply in response to determining that the overcurrent of the first power corresponds to current sharing.

[0005] In a third aspect, a digital signal controller for a power supply unit is described. The digital signal controller includes a processor and a non-transitory computer-readable medium storing instructions that, when used by the processor, cause a set of functions to be performed. The set of functions includes detecting an overcurrent of the power supply unit. The set of functions includes determining that the overcurrent of the power supply unit corresponds to current sharing between the power supply unit and another power supply unit. The set of functions includes suppressing the overcurrent protection mode of the power supply in response to determining that the overcurrent of the power corresponds to current sharing.

[0006] These and other aspects, advantages, and alternatives will become apparent to those of ordinary skill in the art by reading the following detailed description and, where appropriate, referring to the accompanying drawings. Brief Description of the Drawings

[0007] Figure 1A Depicts a plurality of power supply units according to an exemplary implementation;

[0008] Figure 1B Depicts a first power supply unit among multiple power supply units according to an exemplary implementation;

[0009] Figure 2 Depicts a feedback diagram of a power supply unit according to an exemplary implementation;

[0010] Figure 3 Depicts a part of the state machine of a digital signal controller according to an exemplary implementation;

[0011] Figure 4A Depicts the current outputs of two power supply units in a first context according to an exemplary implementation;

[0012] Figure 4B Depicts the current outputs of two power supply units in a second context according to an exemplary implementation;

[0013] Figure 5 Depicts a flowchart of a method according to an exemplary implementation. Detailed Description

[0014] Some example methods and systems are described herein. The words "example", "exemplary", and "illustrative" are used herein to mean "serving as an example, instance, or illustration". Any embodiment or feature described herein as "example", as "exemplary", or as "illustrative" is not necessarily to be construed as preferred or advantageous over other embodiments or features. The exemplary embodiments described herein are not meant to be limiting. It should be readily understood that the aspects of the present disclosure as generally described herein and shown in the figures can be arranged, substituted, combined, separated, and designed in a wide variety of different configurations, all of which are explicitly contemplated herein.

[0015] In an example, multiple power supply units can be connected in parallel to achieve current sharing. This allows the power supply units to combine their load capacities, enabling the system to supply a larger load. However, current sharing can also trigger over-current protection in one or more of the connected power supplies. For example, during the startup phase of current sharing, the first power supply unit may encounter a load that is low enough for the multiple connected power supply units but higher than the load capacity of the first power supply unit. This causes the first power supply unit to perform over-current protection in order to maintain the service life of the first power supply unit. For example, this protection can be embedded in the firmware of the digital signal controller of the first power supply unit.

[0016] While overcurrent protection is desirable in most contexts, in the context of current sharing, overcurrent protection can delay the system from providing power to the load or cause the system to be unable to provide sufficient power to the load. For example, since the first power supply unit performs overcurrent protection, the second power supply unit can also perform overcurrent protection because the first power supply unit does not share the load. This tug-of-war effect of the power supply unit encountering an excessive load can continue indefinitely or at least until the two power supply units synchronize their startup phases.

[0017] These difficulties of overcurrent protection can be solved by establishing feedback communication between two or more current-sharing power supply units. However, this two-way feedback requires additional pins in the integrated circuit embedded in the power supply unit and may involve unnecessary manufacturing and assembly costs for multiple power supply units.

[0018] The examples described herein solve these problems by allowing suppression of the overcurrent protection cases performed by the power supply unit. In particular, a firmware update for the digital signal controller of the power supply unit can allow the power supply unit to detect scenarios in which overcurrent protection is being performed due to current sharing between two or more power supply units. For example, each power supply unit can be a switched-mode power supply unit.

[0019] In the example, the power supply unit detects overcurrent based on being connected to an excessive load. Then, the power supply unit determines whether the overcurrent corresponds to current sharing between multiple power supply units. If the power supply unit detects that the overcurrent corresponds to current sharing, the power supply unit can suppress the overcurrent protection mode. This allows the power supply unit and other power supply units in the multiple power supply units to reach an appropriate current level for powering the load.

[0020] In the example, determining whether the overcurrent corresponds to current sharing between multiple power supply units includes iteratively detecting the overcurrent of the power supply unit and incrementing an overcurrent counter each time an overcurrent is detected; and determining whether the overcurrent counter is greater than a debounce number associated with current sharing. Debounce in this context involves removing the oscillation of the current caused by performing the overcurrent protection mode. If the counter is greater than the debounce number, it is determined that the overcurrent is not due to current sharing, and the power supply unit performs the overcurrent protection mode. On the contrary, if the counter is less than the debounce number, the power supply unit determines to wait for one or more iterations to determine whether the overcurrent is no longer detected. The debounce number can be set based on the time of each iteration and the maximum allowable exposure of the power supply unit to the overcurrent. In this way, the power supply unit can prevent damage caused by prolonged overcurrent while also allowing additional time to adapt to the current sharing context.

[0021] Reference will now be made in detail to various embodiments, examples of which are illustrated in the accompanying drawings. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure and the described embodiments. However, the present disclosure may be practiced without these specific details. In other instances, well-known methods, procedures, components, and circuits have not been described in detail so as not to unnecessarily obscure aspects of the embodiments.

[0022] Figure 1A Depicts a plurality of power supply units according to an exemplary implementation. In particular, Figure 1A Shows a plurality of power supply units 100, which include a first power supply unit 102, a second power supply unit 104, and an nth power supply unit 106. Individually, each power supply unit has a separate load capacity. As Figure 1A Shown, connecting the power supplies in parallel allows for current sharing among the plurality of power supply units 100, which increases the load capacity. However, as described above, the startup phase of current sharing may cause overcurrent protection to be performed in each power supply unit. Systems and methods for solving this problem are further described below.

[0023] Figure 1B Depicts the first power supply unit 102 among a plurality of power supply units 100 according to an exemplary implementation. Specifically, Figure 1B Shows that the first power supply unit includes one or more processors 108, a memory 110, and instructions 112. The one or more processors 108 can be a general-purpose processor or a dedicated processor corresponding to processing visual communication signals. The one or more processors 108 can be configured to use the instructions 112 (e.g., computer-readable program instructions), which are stored in the memory 110 and are executable to provide the functions of the first power supply unit 102 or related systems.

[0024] The memory 110 includes a computer-readable storage medium that can be accessed and executed by the one or more processors 108. The memory can include volatile and / or non-volatile storage components, such as optical, magnetic, organic, or other memory or disk storage, which can be integrated with the processor wholly or in part. For example, the memory can correspond to the firmware of the digital signal controller of the first power supply unit 102. For example, the firmware is stored in a non-volatile memory device of the digital signal controller, such as ROM, EPROM, EEPROM, or flash memory. Thus, the memory is considered a non-transitory computer-readable medium. Instructions executable by one or more processors are stored on the memory 110. The instructions 112 include computer-executable code.

[0025] Figure 2 Depicts a feedback diagram of a power supply unit according to an exemplary implementation. In particular, Figure 2A feedback diagram 200 is shown that facilitates voltage droop control of a power supply unit such as an AC-DC or DC-DC converter. Figure 2 The example shown depicts feedback during current sharing and when there is an increasing load. Figure 2 A bias 202 and a dual feedback loop 204 are shown that are used as system feedback. For example, the dual feedback loop 204 can be applicable to a DC-DC converter. The dual feedback loop 204 includes a converter 206, a voltage proportional integral controller 208, and a current proportional integral controller 210. The bias 202 is derived based on the output of the converter 206. The converter 206 also receives feedback from the voltage proportional integral controller 208 and the current proportional integral controller 210. In summary, the droop control of the bias 202 results in , where , is the reference voltage of the DC-DC feedback loop, is the nominal voltage when there is no current sharing, is the droop voltage coefficient, is the output load current in the power supply unit, is the maximum allowable current sharing per power supply unit, and is the maximum allowable swing of the output voltage of the power supply unit.

[0026] In an exemplary scenario of the feedback diagram 200, the droop control of the power supply unit allows for current sharing to be achieved. However, difficulties may arise during transition events such as the startup phase of current sharing between multiple power supply units. In an illustrative example scenario, two 10A power supply units are connected in parallel and are configured to share current in order to share a 20A load. Starting both power supply units simultaneously should enable the power supply units to equally share the load. However, for example, if one power supply unit starts slightly earlier than the other, the first power supply unit will be expected to carry the 20A load alone. This causes the first power supply to enter an overcurrent protection mode, in which the first power supply unit shuts down for a period of time or is periodically turned on and off. Since the first power supply unit is in the overcurrent protection mode, it is similarly expected that the second power supply unit will carry the entire 20A load, and this similarly causes the second power supply unit to enter the overcurrent protection mode.

[0027] Thus, while a feedback loop with droop control as depicted in, for example, Figure 2 may generally be sufficient on its own to facilitate current sharing between multiple power supply units, there can be some contexts that prevent effective current sharing. Figure 3 Examples that help overcome these difficulties are described in

[0028] Figure 3Depicts a portion of a state machine of a digital signal controller according to an exemplary implementation. In particular, Figure 3 Shows a flowchart of a method 300 for automatically detecting a current sharing context of a power supply unit that has experienced overcurrent. Method 300 includes a starting point 302. Starting point 302 can be a module in the state machine that is periodically revisited by a digital signal controller of the power supply unit. For example, starting point 302 is the start of an iterative process for identifying the current sharing context of the power supply unit.

[0029] At decision block 304, method 300 includes determining whether overcurrent is detected. For example, this can involve detecting a current that is greater than what is expected for the load capacity of a given power supply unit. The current level output by the power supply unit can be compared with an overcurrent threshold to detect the presence or absence of overcurrent. A larger current can indicate that the power supply unit is connected to a relatively large load without the contribution of another power supply unit. For example, this can occur in the context described above with reference to Figure 2 If no overcurrent is detected, method 300 proceeds to block 306, which sets the overcurrent detection count to zero. This indicates in subsequent iterations that the iteration did not find overcurrent. Finally, method 300 proceeds to an end point 308, which completes the iteration.

[0030] If overcurrent is detected, method 300 proceeds from decision block 304 to block 310. At block 310, method 300 includes incrementing the overcurrent detection count. This represents the number of consecutive iterations in which overcurrent has been detected. Method 300 proceeds from block 310 to decision block 312. At decision block 312, the overcurrent detection count is compared with a debounce value. The debounce value is a threshold number related to avoiding oscillations in the current caused by a previously performed overcurrent protection mode. The debounce value can be determined based on a timer for each iteration of method 300 (e.g., using an average iteration time) and a maximum amount of time that the power supply unit is exposed to overcurrent. If the overcurrent detection count exceeds the debounce value, the power supply unit determines that the overcurrent detection is not due to current sharing, and method 300 continues to block 314. At block 314, method 300 includes performing an overcurrent protection mode. As described above, this includes shutting down the power supply unit, or periodically turning the power on and off. In this way, after waiting for a threshold number of iterations, method 300 continues to protect the power supply unit from overcurrent.

[0031] If the current detection count does not exceed the anti-jitter value, the power supply unit does not enter the overprotection mode, and method 300 proceeds to end point 308. If in the next iteration, the decision block 304 does not detect overprotection, it is determined that the overcurrent is due to current sharing, and the power supply unit is allowed to be set to a lower current level. Therefore, determining that the overcurrent is associated with current sharing among multiple power supply units may involve: in the first iteration, determining that the overcurrent detection count is greater than zero but less than the anti-jitter value, and in the second iteration, detecting no overcurrent of the supply current. Figure 4B Further details regarding this process are described in

[0032] The Figure 3 Implementing the process shown into the firmware of the power supply unit can achieve a closed-loop feedback mechanism for each power supply unit, which detects current sharing without communication between multiple power supply units. This reduces the number of connections between system components and potentially frees up pins in the digital signal controller of each power supply unit. This architecture can be implemented in AC-DC converters, DC-DC converters, quasi-resonant LLC converters, or other power supply applications including digital signal processors for power transfer.

[0033] Figure 4A depicts the current outputs of two power supply units in a first context according to an exemplary implementation. In particular, Figure 4A shows a graph 400 of the first current output level 402 of the first power supply unit and the second current output level 404 of the second power supply unit during the steady state of current sharing. In Figure 4A the example depicted, the power supply units are current sharing to share the load using the closed-loop feedback architecture described above. In the steady state, the first current output level 402 of the first power supply unit and the second current output level 404 of the second power supply unit are almost the same (e.g., sharing the load within 5% of each other).

[0034] Figure 4B depicts the current outputs of two power supply units in a second context according to an exemplary implementation. In particular, Figure 4B shows a graph 410 of the first current output level 412 of the first power supply unit and the second current output level 414 of the second power supply unit during the start-up phase 416 and the steady-state phase 418 of current sharing. As Figure 4BAs shown, during startup phase 416, the first power unit turns on earlier than the second power unit and thus has a relatively high current level (e.g., higher than threshold current 420). However, instead of entering an overcurrent protection mode, the first power unit iterates through method 300 multiple times to verify whether the overcurrent corresponds to startup phase 416. Before the overcurrent detection count exceeds the debounce value, startup phase 416 ends and the overcurrent drops below threshold current 420. The currents then converge until they become nearly the same at steady state phase 418.

[0035] Figure 5 A flowchart depicting method 500 according to one exemplary implementation is shown. Figure 5 The method 500 shown presents an example of a method that can be used with multiple power source units, such as multiple power units 100. Additionally, a device or system can be used or configured to perform Figure 5 the logic functions shown. Method 500 can include one or more operations, functions, or actions shown in one or more of blocks 502 - 506. Although these blocks are shown in sequential order, these blocks can also be performed in parallel and / or in a different order than described herein. Moreover, individual blocks can be combined into fewer blocks, divided into additional blocks, and / or removed based on the desired implementation.

[0036] For this and other processes and methods disclosed herein, the flowchart illustrates the functionality and operations of one possible implementation of the example. Each block or some portion of each block can represent a module, segment, or portion of program code that includes one or more instructions executable by a processor to implement a particular logical function or step in the process. The program code can be stored on any type of computer readable medium or data storage, such as a storage device including a disk or hard drive. Additionally, the program code can be encoded in a machine readable format on a computer readable storage medium or encoded on other non - transitory media or articles. The computer readable medium can include non - transitory computer readable media or memories, such as computer readable media that stores data for a short period of time, such as register memory, processor cache, and random access memory (RAM). For example, the computer readable medium can also include non - transitory media, such as auxiliary or persistent long - term storage, such as read only memory (ROM), optical or magnetic disks, compact disc read only memory (CD - ROM). The computer readable medium can also be any other volatile or non - volatile storage system. For example, the computer readable medium can be considered a tangible computer readable storage medium.

[0037] Additionally, Figure 5Each box, or some parts of each box, within and in other processes and methods disclosed herein may represent circuitry wired to perform a particular logical function in the process. For example, an MCU, a dedicated processor, an analog control circuit, etc. may be used to perform the boxes described with respect to method 500. Those skilled in the art should understand that within the scope of the examples of the present disclosure, some alternative implementations are included, where functions may not be performed in the order shown or discussed, including substantially simultaneously or in the reverse order, depending on the functions involved.

[0038] At block 502, method 500 includes detecting an overcurrent of a first power supply unit among a plurality of power supply units. For example, this may include comparing the output current of the first power supply unit with a threshold current. The threshold current may correspond to the maximum load rating of the first power supply unit, and connecting the first power supply unit to a load greater than the maximum rating may cause the load to draw a current higher than the threshold level.

[0039] At block 504, method 500 includes determining that the overcurrent of the first power supply unit corresponds to current sharing among the plurality of power supply units. For example, this may be performed as described above with reference to Figure 3 In these examples, method 500 may be associated with instructions embedded in the firmware of the first power supply unit, and the steps of method 500 may be performed based on the instructions stored in the firmware.

[0040] At block 506, in response to determining that the overcurrent of the first power supply corresponds to current sharing, inhibit the overcurrent protection mode of the first power supply. For example, although the first power supply unit may typically enter the overcurrent protection mode every time the output current exceeds the threshold current, the first power supply unit may alternatively delay entering the overcurrent protection mode until method 300 is completed.

[0041] In an example, method 500 further includes detecting an overcurrent of a second power supply unit among the plurality of power supply units in parallel with detecting the overcurrent of the first power supply unit. For example, the second power supply unit may also detect an overcurrent during the startup phase. Method 500 may further include determining that the overcurrent of the second power supply unit corresponds to current sharing among the plurality of power supply units, and in response to determining that the overcurrent of the second power supply corresponds to current sharing, inhibiting the overcurrent protection mode of the first power supply. Thus, at the system level, multiple power supply units may perform method 300 in parallel to determine whether the overcurrent is associated with current sharing of the power supply units. In an alternative example, as shown in Figure 4B For example, the first power supply unit may detect an overcurrent while the second power supply unit may not detect an overcurrent.

[0042] In an example, determining that an overcurrent of a first power supply unit corresponds to current sharing among a plurality of power supply units includes delaying entry into an overcurrent protection mode and, while delaying entry into the overcurrent protection mode, determining that an output current has decreased to a current level below a threshold overcurrent level of the first power supply unit. For example, this can be performed with respect to the first power supply unit as Figure 4B shown.

[0043] In an example, determining that an overcurrent of a first power supply corresponds to current sharing among a plurality of power supply units includes iteratively detecting an overcurrent of the first power supply unit, incrementing an overcurrent counter each time an overcurrent is detected, and determining that the overcurrent counter is less than a debounce value associated with current sharing. For example, this can be performed as described above with reference to Figure 3 that.

[0044] In a related example, method 500 further includes, before determining that the overcurrent counter is less than the debounce value, in response to determining that the overcurrent counter is greater than the debounce value associated with current sharing, performing an overcurrent protection mode for the first power supply. Thus, in an example, the first power supply unit can determine at a first time that an overcurrent does not correspond to current sharing and can determine at a second time that the overcurrent does correspond to current sharing.

[0045] In a related example, method 500 includes setting the debounce value based on the time of each iteration and a threshold time for the first power supply unit to be exposed to an overcurrent, where each iteration corresponds to detecting an overcurrent of the first power supply unit.

[0046] In an example, determining that an overcurrent of a first power supply corresponds to current sharing among a plurality of power supply units includes: during a first iteration, detecting an overcurrent of the first power supply unit, incrementing an overcurrent counter in response to detecting the overcurrent, determining that the overcurrent counter is less than a debounce value associated with current sharing, and, during a second iteration immediately following the first iteration, not detecting an overcurrent of the first power supply unit. For example, this can be performed as described above with reference to Figure 3 that.

[0047] Accordingly, the described embodiments provide systems and methods for reliably facilitating current sharing among a plurality of power source units, thereby enabling a power supply system to handle higher loads. Additionally, by embedding the process for reviewing overcurrents in the firmware of a digital signal controller of a power source unit, each power source unit is able to determine whether to enter an overcurrent protection mode without receiving feedback from another power source unit.

[0048] The specific arrangements shown in the figures should not be considered limiting. It should be understood that other embodiments may include more or fewer of each element shown in a given figure. Additionally, some of the shown elements may be combined or omitted. Moreover, an exemplary embodiment may include elements not shown in the figures.

[0049] Although various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for illustrative purposes and not limiting, with the true scope being indicated by the appended claims.

Claims

1. A system for overcurrent protection situation suppression, the system comprising: Multiple power supply units; A processor; And A non-transitory computer-readable medium having instructions stored thereon, the instructions when used by the processor cause a set of functions to be performed, the functions including: Detecting an overcurrent of a first power supply unit among the multiple power supply units; Determining that the overcurrent of the first power supply unit corresponds to current sharing among the multiple power supply units, wherein determining that the overcurrent of the first power supply unit corresponds to current sharing among the multiple power supply units includes: Iteratively detecting the overcurrent of the first power supply unit; Incrementing an overcurrent counter each time an overcurrent is detected; and Determining that the overcurrent counter is less than a debounce value associated with current sharing; and In response to determining that the overcurrent of the first power supply unit corresponds to the current sharing, suppressing the overcurrent protection mode of the first power supply unit.

2. The system according to claim 1, wherein, The multiple power supply units are connected in parallel.

3. The system according to claim 1, wherein, The multiple power supply units are configured to share current without feedback information being transmitted between the multiple power supply units.

4. The system according to claim 1, wherein, Each power supply unit includes a switched-mode power supply unit.

5. The system according to claim 1, wherein, The set of functions further includes: Before determining that the overcurrent counter is less than the debounce value, in response to determining that the overcurrent counter is greater than the debounce value associated with current sharing, performing the overcurrent protection mode of the first power supply unit.

6. The system according to claim 5, wherein, The set of functions further includes: Setting the debounce value based on the time of each iteration and a threshold time for the first power supply unit to be exposed to the overcurrent, wherein each iteration corresponds to detecting the overcurrent of the first power supply unit.

7. The system according to claim 1 further includes a DC-DC converter, wherein, The DC-DC converter includes the multiple power supply units.

8. The system according to claim 1, further comprising an AC-DC converter, wherein, The AC-DC converter includes the multiple power supply units.

9. The system according to claim 1 further includes a quasi-resonant LLC converter, wherein, The quasi-resonant LLC converter includes the multiple power supply units.

10. The system according to claim 1 further includes a digital signal controller, wherein, The digital signal controller includes the processor and the non-transitory computer-readable medium, wherein the non-transitory computer-readable medium is the firmware of the digital signal controller, and wherein the set of functions is part of a state machine embedded in the firmware.

11. A method for overcurrent protection situation suppression, the method comprising: Detecting an overcurrent of a first power supply unit among multiple power supply units; Determining that the overcurrent of the first power supply unit corresponds to current sharing among the multiple power supply units, wherein determining that the overcurrent of the first power supply unit corresponds to current sharing among the multiple power supply units includes: Iteratively detecting the overcurrent of the first power supply unit; Incrementing an overcurrent counter each time an overcurrent is detected; and Determining that the overcurrent counter is less than a debounce value associated with current sharing; and In response to determining that the overcurrent of the first power supply unit corresponds to the current sharing, suppressing the overcurrent protection mode of the first power supply unit.

12. The method according to claim 11, further comprising: In parallel with detecting the overcurrent of the first power supply unit, detecting an overcurrent of a second power supply unit among the multiple power supply units; Determine that an overcurrent of the second power supply unit corresponds to current sharing among the multiple power supply units; and In response to determining that the overcurrent of the second power supply unit corresponds to the current sharing, inhibit the overcurrent protection mode of the first power supply unit.

13. The method according to claim 11, wherein, Determining that an overcurrent of the first power supply unit corresponds to current sharing among the multiple power supply units includes: Delaying the overcurrent protection mode; and When delaying the overcurrent protection mode, determine that the output current has decreased to a current level below the threshold overcurrent level of the first power supply unit.

14. The method according to claim 11, further comprising: Before determining that the overcurrent counter is less than the debounce value, in response to determining that the overcurrent counter is greater than the debounce value associated with current sharing, execute the overcurrent protection mode of the first power supply unit.

15. The method according to claim 14, further comprising: Set the debounce value based on the time of each iteration and a threshold time for the first power supply unit to be exposed to the overcurrent, where each iteration corresponds to detecting an overcurrent of the first power supply unit.

16. The method according to claim 11, wherein, Determining that an overcurrent of the first power supply unit corresponds to current sharing among the multiple power supply units includes: During a first iteration, detect an overcurrent of the first power supply unit; Increment an overcurrent counter in response to detecting the overcurrent; Determine that the overcurrent counter is less than the debounce value associated with current sharing; and During a second iteration immediately following the first iteration, no overcurrent of the first power supply unit is detected.

17. A digital signal controller for a first power supply unit, comprising: A processor; and A non-transitory computer-readable medium having instructions stored thereon that, when used by the processor, cause a set of functions to be performed, the functions including: Detect an overcurrent of the first power supply unit; Determine that the overcurrent of the first power supply unit corresponds to current sharing between the first power supply unit and a second power supply unit, where determining that the overcurrent of the first power supply unit corresponds to the current sharing includes: Iteratively detect an overcurrent of the first power supply unit; Increment an overcurrent counter each time an overcurrent is detected; and Determine that the overcurrent counter is less than the debounce value associated with current sharing; and In response to determining that the overcurrent of the first power supply unit corresponds to the current sharing, inhibit the overcurrent protection mode of the first power supply unit.

18. The digital signal controller according to claim 17, wherein, The non-transitory computer-readable medium is the firmware of the digital signal controller, where the set of functions is part of a state machine embedded in the firmware.

19. The digital signal controller according to claim 17, the set of functions further including: In parallel with detecting an overcurrent of the first power supply unit, detect an overcurrent of a second power supply unit; Determine that the overcurrent of the second power supply unit corresponds to current sharing; and In response to determining that the overcurrent of the second power supply unit corresponds to the current sharing, inhibit the overcurrent protection mode of the first power supply unit.

20. The digital signal controller according to claim 17, wherein, Determining that the overcurrent of the first power supply unit corresponds to the current sharing includes: Delay the overcurrent protection mode; and When delaying the overcurrent protection mode, determine that the output current has decreased to a current level below the threshold overcurrent level of the first power supply unit.

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