Over-current detection device, protection device and abnormity early warning method

Abstract

The invention relates to an overcurrent detection device, a protection device and an abnormity early warning method. The overcurrent detection device comprises: a sampling unit configured to sample a first measuring unit to obtain a first current value; a transmit-receive unit configured to receive second to Nth current values from (N-1) other overcurrent detection devices; a difference value calculation unit configured to calculate first to (N-1) th current difference values, the first to (N-1) th current difference values representing current difference values between the first current value and the second to Nth current values, respectively; and the early warning output unit is configured to output a first early warning signal when the first current difference value to the (N-1) th current difference value are respectively greater than the first difference value threshold value to the (N-1) th difference value threshold value. The over-current detection device can compare the current values of a plurality of over-current detection devices running in parallel, and the panoramic fault monitoring and early warning capability of the valve control system is enhanced.

Description

Overcurrent detection device, protection device and abnormality warning method Technical Field

[0001] The present application relates to the field of power system energy storage technology, and in particular to an overcurrent detection device, a protection device, and an abnormality warning method. Background Art

[0002] The new energy storage valve control system is the core control device of the new energy storage system. During operation, the overcurrent detection device in the energy storage valve control system may experience communication interruption, program errors, program bugs, CPU crashes, and abnormal crashes, which may affect the commissioning and decommissioning of the entire converter station. Therefore, timely warning of abnormal overcurrent detection device operation is crucial.

[0003] In traditional technologies, there is a problem that the early warning strategy for valve control systems is not comprehensive enough, especially in the field of new ultra-high voltage energy storage, where the reliability requirements for valve control systems are more stringent.

[0004] Summary of the Invention

[0005] In view of the above problems, the present application provides an overcurrent detection device, a protection device and an abnormality warning method, which can enhance the ability to warn of abnormalities in the overcurrent detection device and make the warning strategy in the energy storage valve control system more perfect.

[0006] In a first aspect, the present application provides an overcurrent detection device, which operates in parallel with N-1 other overcurrent detection devices in an N-to-M redundant structure of an energy storage valve control system, where N is an integer greater than or equal to 3 and M is an integer less than N. The overcurrent detection device is communicatively connected to the N-1 additional overcurrent detection devices, respectively, and the overcurrent detection device includes: a sampling unit, which is configured to sample the first measuring unit to obtain a first current value; a transceiver unit, which is configured to receive, from the N-1 additional overcurrent detection devices, the second current value to the N-th current value obtained by each overcurrent detection device sampling the corresponding measuring unit; a difference calculation unit, which is configured to calculate the first current difference value to the N-1th current difference value, the first current difference value to the N-1th current difference value representing the current difference between the first current value and the second current value to the N-1th current value; and an early warning output unit, which is configured to output a first early warning signal when the first current difference value to the N-1th current difference value are respectively greater than the first difference threshold value to the N-1th difference threshold value corresponding to the first current difference value to the N-1th current difference value, the first early warning signal indicating that the overcurrent detection device is abnormal.

[0007] In the technical solution of the embodiment of the present application, the overcurrent detection device receives the current values ​​of N-1 other overcurrent detection devices through a transceiver unit, calculates the current difference between the overcurrent detection device and the other N-1 overcurrent detection devices through a difference calculation unit, and outputs a first warning signal through a warning output unit when all of these N-1 current differences exceed the corresponding difference threshold value. Thus, when the current of the overcurrent detection device deviates significantly from the current of the other N-1 overcurrent detection devices operating in parallel, the user can be notified of an abnormality in the overcurrent detection device, thereby achieving an early warning of an abnormality in the overcurrent detection device. Accordingly, the ability to provide early warning of an abnormality in the overcurrent detection device is enhanced, making the early warning strategy in the energy storage valve control system more complete, and thereby improving the reliability and safety of the valve control system.

[0008] In some embodiments, the difference calculation unit is configured to respectively calculate the current differences between the Kth current value from the second current value to the Nth current value and the remaining current values ​​from the second current value to the Nth current value. The warning output unit is further configured to output a second warning signal when the K-1th current difference from the first current difference to the N-1th current difference is greater than the K-1th difference threshold value, the remaining N-2 current differences are less than or equal to the corresponding difference threshold values, and the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value are respectively greater than the corresponding difference threshold values, the second warning signal indicates that the overcurrent detection device that samples the Kth current value is abnormal.

[0009] When the current difference between this overcurrent detection device and only one other overcurrent detection device is greater than the corresponding difference threshold value, the early warning output unit implements abnormal early warning for the other N-1 overcurrent detection devices based on the comparison of the current difference between the other N-1 overcurrent detection devices with the corresponding difference threshold value.

[0010] In some embodiments, the overcurrent detection device also includes: a storage unit, which is configured to store multiple first current values ​​to Nth current values ​​in association with a sampling sequence number within a predetermined time period including multiple time sections; a difference threshold value calculation unit, which is configured to calculate the first difference threshold value to the N-1th difference threshold value based on the stored multiple first current values ​​to Nth current values ​​when each current value of the stored multiple first current values ​​to Nth current values ​​is within a preset current range, and calculate the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value.

[0011] By dynamically calculating and updating the difference threshold value in real time through the difference threshold value calculation unit, an overcurrent detection device having abnormal sampling values ​​relative to other overcurrent detection devices can be found more accurately.

[0012] In some embodiments, the difference calculation unit is configured to: calculate, at each time segment within the predetermined time period, the first current difference to the N-1th current difference between the stored first current value and the stored second current value to the N-th current value according to the corresponding sampling sequence number, and calculate the current differences between the K-th current value among the stored second current value to the N-th current value and the remaining current values ​​from the second current value to the N-th current value. The difference threshold calculation unit is configured to: calculate the first difference threshold to the N-1th difference threshold based on the first current difference to the N-1th current difference at each time segment; and calculate the difference thresholds of the K-th current value relative to the remaining current values ​​from the second current value to the N-th current value based on the current differences between the K-th current value and the remaining current values ​​from the second current value to the N-th current value at each time segment.

[0013] The difference calculation unit calculates the current difference from the first current difference to the N-1th current difference at multiple time sections, as well as the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at multiple time sections, so that the difference threshold value calculation unit can correspondingly obtain more reliable and accurate first difference threshold value to the N-1th difference threshold value, as well as the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value.

[0014] In some embodiments, the difference calculation unit is configured to calculate an average value of each of the multiple first current differences to the multiple N-1th current differences at the multiple time sections to obtain first difference typical values ​​to N-1th difference typical values; calculate the average values ​​of the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at the multiple time sections to obtain respective typical difference values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value. The difference threshold calculation unit is configured to calculate the product of the first difference typical value to the N-1th difference typical value and a preset threshold coefficient to obtain first difference threshold values ​​to the N-1th difference threshold; and calculate the product of each difference typical value of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value and the preset threshold coefficient to obtain respective difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value.

[0015] The difference calculation unit calculates the average value of each of the multiple first current differences to the multiple N-1th current differences under multiple time sections, and obtains the first difference typical value to the N-1th difference typical value. Then, the difference threshold value calculation unit supplements each difference typical value with a preset threshold coefficient, thereby improving the accuracy of the difference threshold value and making the horizontal data comparison result more accurate.

[0016] In the second aspect, the present application provides an abnormality warning method. The method is applied to an N-out-of-M redundant structure in an energy storage valve control system, where N is an integer greater than or equal to 3, and M is an integer less than N. The N-out-of-M redundant structure includes a first overcurrent detection device to an N-th overcurrent detection device operating in parallel, and a protection device, wherein the first overcurrent detection device to the N-th overcurrent detection device are suitable for sampling the first measurement unit to the N-th measurement unit to obtain the first current value to the N-th current value, and the protection device is suitable for performing N-out-of-M voting on the overcurrent detection results output by the first overcurrent detection device to the N-th overcurrent detection device and outputting the N-out-M voting result, wherein any overcurrent detection device from the first overcurrent detection device to the N-th overcurrent detection device is communicatively connected to N-1 other overcurrent detection devices respectively, The method is executed by any overcurrent detection device from the first overcurrent detection device to the Nth overcurrent detection device. When the method is executed by the first overcurrent detection device, the method includes: receiving the second current value to the Nth current value from the second overcurrent detection device to the Nth overcurrent detection device respectively; calculating the first current difference to the N-1th current difference, the first current difference to the N-1th current difference representing the current difference between the first current value and the second current value to the Nth current value respectively; and when the first current difference to the N-1th current difference are respectively greater than the first difference threshold value to the N-1th difference threshold value corresponding to the first current difference to the N-1th current difference, outputting a first warning signal, the first warning signal indicating that the first overcurrent detection device is abnormal.

[0017] In the technical solution of the embodiments of the present application, any one overcurrent detection device serves as the master device. The master device then transversely receives the current values ​​of N-1 other overcurrent detection devices, and then obtains the current differences between the master device and the other N-1 overcurrent detection devices. These N-1 current differences are then compared with corresponding difference thresholds. When all N-1 current differences exceed the corresponding difference thresholds, an abnormality warning is issued to the overcurrent detection device serving as the master device. Thus, transverse warnings are achieved by comparing current data between the overcurrent detection devices, improving the reliability and safety of the valve control system.

[0018] In some embodiments, the method also includes: respectively calculating the current differences between the Kth current value from the second current value to the Nth current value and the remaining current values ​​from the second current value to the Nth current value; and when the K-1th current difference from the first current difference to the N-1th current difference is greater than the K-1th difference threshold value, the remaining N-2 current differences are less than or equal to the corresponding difference threshold value, and the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value are respectively greater than the corresponding difference threshold values, outputting a second warning signal, the second warning signal indicating that the Kth overcurrent detection device is abnormal.

[0019] In an embodiment of the present application, when the current difference between any overcurrent detection device and only one other overcurrent detection device is greater than the corresponding difference threshold value, the current difference between the other N-1 overcurrent detection devices is compared with the corresponding difference threshold value, thereby achieving abnormal warning for the other N-1 overcurrent detection devices.

[0020] In some embodiments, the method further includes: storing a plurality of first to Nth current values ​​in association with a sampling sequence number within a predetermined time period including a plurality of time sections; and when each current value among the plurality of first to Nth current values ​​stored is within a preset current range, calculating the first difference threshold value to the N-1th difference threshold value based on the plurality of first to Nth current values ​​stored, and calculating each difference threshold value of the Kth current value relative to the remaining current values ​​among the second current value to the Nth current value.

[0021] Compared with using a pre-set value or a value manually set based on historical data as the difference threshold value between overcurrent detection devices, the embodiment of the present application dynamically calculates and updates the difference threshold value in real time, which can more accurately find the overcurrent detection device with abnormal sampling values ​​relative to other overcurrent detection devices.

[0022] In some embodiments, the calculation of the first difference threshold value to the N-1th difference threshold value, and the calculation of the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value include: at each time section within the predetermined time period, according to the corresponding sampling sequence number, respectively calculating the first current difference to the N-1th current difference between the stored first current value and the stored second current value to the Nth current value, and respectively calculating the current differences between the Kth current value from the stored second current value to the Nth current value and the remaining current values ​​from the second current value to the Nth current value; and respectively calculating the first difference threshold value to the N-1th difference threshold value based on the first current difference to the N-1th current difference at each time section; and respectively calculating the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value based on the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at each time section.

[0023] In the embodiment of the present application, by accumulating the first current difference value to the N-1th current difference value at multiple time sections, more reliable first difference threshold value to the N-1th difference threshold value can be obtained accordingly.

[0024] In some embodiments, the first difference threshold value to the N-1th difference threshold value are calculated based on the first current difference value to the N-1th current difference value at each time section respectively; and the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value are calculated based on the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at each time section respectively, including: calculating the average value of each of the multiple first current differences to the multiple N-1th current differences at the multiple time sections to obtain the first difference typical value to the N-1th difference typical value; calculating the first difference typical value to the N-1th current difference typical value respectively. The product of the typical value of the difference and the preset threshold coefficient is used to obtain the first difference threshold value to the N-1th difference threshold value; the average values ​​of the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value under the multiple time sections are calculated one by one to obtain the typical values ​​of the difference between the Kth current value and the remaining current values ​​from the second current value to the Nth current value; and the product of the typical values ​​of the difference between the Kth current value and the remaining current values ​​from the second current value to the Nth current value and the preset threshold coefficient is calculated to obtain the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value.

[0025] In the embodiment of the present application, the average value of each of the first current difference to the multiple N-1th current difference under multiple time sections is calculated respectively to obtain the first difference typical value to the N-1th difference typical value. By supplementing each difference typical value with a preset threshold coefficient, a more accurate difference threshold value can be obtained, thereby improving the reliability of each difference threshold value.

[0026] In a third aspect, the present application provides a protection device located in an N-out-of-M redundant structure of an energy storage valve control system, where N is an integer greater than or equal to 3, and M is an integer less than N. The protection device is suitable for performing N-out-of-M voting on the overcurrent detection results output by the first overcurrent detection device to the N-th overcurrent detection device running in parallel and outputting the N-out-M voting result. The protection device includes: a receiving unit configured to receive a first current value to an N-th current value from the first overcurrent detection device to the N-th overcurrent detection device, respectively; a difference calculation unit configured to calculate a first current difference to an N-1th current difference, where the first current difference to the N-1th current difference represents the current difference between the first current value and the second current value to the N-1th current value, respectively; and an early warning output unit configured to output a first early warning signal when the first current difference to the N-1th current difference are respectively greater than a first difference threshold to an N-1th difference threshold corresponding to the first current difference to the N-1th current difference, the first early warning signal indicating that the first overcurrent detection device is abnormal.

[0027] In the technical solution of the embodiment of the present application, the first current value to the Nth current value of the first overcurrent detection device to the Nth overcurrent detection device are respectively received by the receiving unit, and then the first current difference to the N-1th current difference of the first current value and the other N-1 current values ​​are respectively obtained by the difference calculation unit based on the first current value, so that the first current difference to the N-1th current difference are respectively compared with the corresponding difference threshold value through the early warning output unit, and when these N-1 current differences all exceed the corresponding difference threshold value, an abnormal early warning of the first overcurrent detection device corresponding to the first current value is realized.

[0028] In some embodiments, the difference calculation unit is configured to respectively calculate the current differences between a Kth current value from the second current value to the Nth current value and the remaining current values ​​from the second current value to the Nth current value. The warning output unit is configured to output a second warning signal when the K-1th current difference from the first current difference to the N-1th current difference is greater than a K-1th difference threshold value, the remaining N-2 current differences are less than or equal to the corresponding difference threshold values, and the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value are greater than the corresponding difference threshold values, wherein the second warning signal indicates that the Kth overcurrent detection device is abnormal.

[0029] When only one of the first current difference to the N-1th current difference is greater than the difference threshold value, for example, when only the K-1th current difference is greater than the K-1th difference threshold value, the early warning output unit compares the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value with the corresponding difference threshold values, thereby realizing abnormal early warning of the second overcurrent detection device to the Nth overcurrent detection device.

[0030] In some embodiments, the protection device further includes: a storage unit configured to store a plurality of first to Nth current values ​​in association with a sampling sequence number within a predetermined time period including a plurality of time sections; and a difference threshold value calculation unit configured to calculate the first difference threshold value to the N-1th difference threshold value based on the stored plurality of first to Nth current values ​​when each current value among the stored plurality of first to Nth current values ​​is within a preset current range, and calculate each difference threshold value of the Kth current value relative to the remaining current values ​​among the second current value to the Nth current value.

[0031] In some embodiments, the difference calculation unit is configured to calculate, at each time segment within the predetermined time period, the first current difference to the N-1th current difference between the stored first current value and the stored second current value to the N-th current value according to the corresponding sampling sequence number, and to calculate the current differences between the K-th current value among the stored second current value to the N-th current value and the remaining current values ​​among the second current value to the N-th current value. The difference threshold calculation unit is configured to calculate the first difference threshold to the N-1th difference threshold based on the first current difference to the N-1th current difference at each time segment; and to calculate the difference thresholds of the K-th current value relative to the remaining current values ​​among the second current value to the N-th current value based on the current differences between the K-th current value and the remaining current values ​​among the second current value to the N-th current value at each time segment.

[0032] In some embodiments, the difference calculation unit is configured to: calculate an average value of each of the multiple first current differences to the multiple N-1th current differences at the multiple time sections to obtain a first difference typical value to an N-1th difference typical value; calculate the average values ​​of the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at the multiple time sections to obtain a respective difference typical value of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value. The difference threshold calculation unit is configured to: calculate the product of the first difference typical value to the N-1th difference typical value and a preset threshold coefficient to obtain a first difference threshold value to the N-1th difference threshold value; and calculate the product of the respective difference typical values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value and the preset threshold coefficient to obtain a respective difference threshold value of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value.

[0033] In a fourth aspect, the present application provides another abnormality warning method. The method is applied to an N-out-of-M redundant structure in an energy storage valve control system, where N is an integer greater than or equal to 3, and M is an integer less than N. The N-out-of-M redundant structure includes a first overcurrent detection device to an N-th overcurrent detection device operating in parallel, and a protection device, wherein the first overcurrent detection device to the N-th overcurrent detection device are suitable for sampling the first measurement unit to the N-th measurement unit to obtain the first current value to the N-th current value, and the protection device is suitable for performing N-out-of-M voting on the overcurrent detection results output by the first overcurrent detection device to the N-th overcurrent detection device and outputting the N-out-M voting result, wherein the method is performed by the protection device. The method includes: receiving first to Nth current values ​​from the first to Nth overcurrent detection devices, respectively; calculating first to N-1th current differences, the first to N-1th current differences representing current differences between the first current value and the second to Nth current values, respectively; and outputting a first warning signal when the first to N-1th current differences are respectively greater than first to N-1th difference thresholds corresponding to the first to N-1th current differences, the first warning signal indicating that the first overcurrent detection device is abnormal.

[0034] In the technical solution of the embodiment of the present application, the protection device is used as the execution body, and the first current value to the Nth current value of the first overcurrent detection device to the Nth overcurrent detection device are respectively received. Based on the first current value, the first current difference to the N-1th current difference of the first current value and the other N-1 current values ​​are respectively obtained, and the first current difference to the N-1th current difference are respectively compared with the corresponding difference threshold value. When these N-1 current differences all exceed the corresponding difference threshold value, an abnormal warning is issued to the first overcurrent detection device corresponding to the first current value. Similarly, a horizontal warning is achieved by comparing the current data between each overcurrent detection device.

[0035] In some embodiments, the method also includes: respectively calculating the current differences between the Kth current value from the second current value to the Nth current value and the remaining current values ​​from the second current value to the Nth current value; and when the K-1th current difference from the first current difference to the N-1th current difference is greater than the K-1th difference threshold value, the remaining N-2 current differences are less than or equal to the corresponding difference threshold value, and the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value are greater than the corresponding difference threshold value, outputting a second warning signal, the second warning signal indicating that the Kth overcurrent detection device is abnormal.

[0036] In the embodiment of the present application, when the protection device is used as the execution body, abnormal warning of the second overcurrent detection device to the Nth overcurrent detection device can also be achieved.

[0037] In some embodiments, the method further includes: storing a plurality of first to Nth current values ​​in association with a sampling sequence number within a predetermined time period including a plurality of time sections; and when each current value among the plurality of first to Nth current values ​​stored is within a preset current range, calculating the first difference threshold value to the N-1th difference threshold value based on the plurality of first to Nth current values ​​stored, and calculating each difference threshold value of the Kth current value relative to the remaining current values ​​among the second current value to the Nth current value.

[0038] In some embodiments, the calculation of the first difference threshold value to the N-1th difference threshold value, and the calculation of the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value, include: at each time section within the predetermined time period, calculating the first current difference to the N-1th current difference between the stored first current value and the stored second current value to the Nth current value according to the corresponding sampling sequence number, and calculating the current differences between the Kth current value from the stored second current value to the Nth current value and the remaining current values ​​from the second current value to the Nth current value; and calculating the first difference threshold value to the N-1th difference threshold value based on the first current difference to the N-1th current difference at each time section; and calculating the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value based on the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at each time section.

[0039] In some embodiments, the first difference threshold value to the N-1th difference threshold value are calculated based on the first current difference value to the N-1th current difference value at each time section respectively; and the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value are calculated based on the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at each time section respectively, including: calculating the average value of each of the multiple first current differences to the multiple N-1th current differences at the multiple time sections to obtain the first difference typical value to the N-1th difference typical value; calculating the first difference typical value to the N-1th current difference typical value respectively. The product of the typical value of the difference and the preset threshold coefficient is used to obtain the first difference threshold value to the N-1th difference threshold value; the average values ​​of the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value under the multiple time sections are calculated one by one to obtain the typical values ​​of the difference between the Kth current value and the remaining current values ​​from the second current value to the Nth current value; and the product of the typical values ​​of the difference between the Kth current value and the remaining current values ​​from the second current value to the Nth current value and the preset threshold coefficient is calculated to obtain the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value.

[0040] In a fifth aspect, the present application further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method described in the second or fourth aspect.

[0041] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] FIG1 is a schematic structural diagram of a portion of an energy storage valve control system in conventional technology;

[0043] FIG2 is a diagram illustrating an application environment of an overcurrent detection device according to some embodiments of the present application;

[0044] FIG3 is a schematic structural diagram of an overcurrent detection device according to some embodiments of the present application;

[0045] FIG4 is a schematic diagram of a specific structure of an overcurrent detection device according to some embodiments of the present application;

[0046] FIG5 is a diagram illustrating an application environment of an overcurrent detection device according to other embodiments of the present application;

[0047] FIG6 is a schematic structural diagram of an overcurrent detection device according to other embodiments of the present application;

[0048] FIG7 is a schematic diagram of the specific structure of an overcurrent detection device according to other embodiments of the present application;

[0049] FIG8 is a flow chart of an abnormality warning method performed by an overcurrent detection device according to some embodiments of the present application;

[0050] FIG9 is a schematic diagram of a specific flow of an abnormality warning method performed by an overcurrent detection device according to some embodiments of the present application;

[0051] FIG10 is a flow chart of an abnormality warning method performed by an overcurrent detection device according to other embodiments of the present application;

[0052] FIG11 is a schematic diagram of a specific flow chart of an abnormality warning method performed by an overcurrent detection device according to other embodiments of the present application;

[0053] FIG12 is a schematic diagram showing the correspondence between sampling sequence number differences and sampling data of an overcurrent detection device according to some embodiments of the present application;

[0054] FIG13 is a diagram illustrating an application environment of a protection device according to some embodiments of the present application;

[0055] FIG14 is a schematic structural diagram of a protection device according to some embodiments of the present application;

[0056] FIG15 is a schematic diagram of a specific structure of a protection device according to some embodiments of the present application;

[0057] FIG16 is a diagram illustrating an application environment of a two-out-of-three protection device according to other embodiments of the present application;

[0058] FIG17 is a schematic structural diagram of a two-out-of-three protection device according to other embodiments of the present application;

[0059] FIG18 is a schematic diagram of the specific structure of a two-out-of-three protection device according to other embodiments of the present application;

[0060] FIG19 is a flow chart of an abnormality warning method performed by a protection device according to some embodiments of the present application; and

[0061] FIG20 is a flow chart of an abnormality warning method performed by a two-out-of-three protection device according to other embodiments of the present application. DETAILED DESCRIPTION

[0062] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0063] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0064] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0065] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least some embodiments of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0066] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0067] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0068] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0069] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; internal connections between two components or interactions between two components. Those skilled in the art can understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.

[0070] The accuracy of the overcurrent detection results of the energy storage valve control system is related to whether the converter valve can operate stably. In daily operation, the overcurrent detection device in the energy storage valve control system may have problems such as communication interruption, program failure, abnormal crash, etc., which in turn affect the overcurrent detection results of the converter valve. At present, overcurrent detection devices and three-out-of-two protection devices are used to independently perform protection actions, judgment of sampling values ​​and their early warning. However, this processing method is to make isolated judgments in the vertical direction of the data flow, and only consider the comparison between the protection set value and the real-time analog quantity of a single overcurrent detection device. The early warning strategy is not comprehensive enough. By increasing the horizontal data comparison between the overcurrent detection devices, the inventor can also issue early warnings for abnormally operating overcurrent detection devices, making the early warning strategy in the energy storage valve control system more perfect.

[0071] The new energy storage valve control system currently follows the regulatory requirements of the "Zhangbei ±35kV DC Energy Storage Project Flexible Direct Current Energy Storage Device Technical Specifications": valve-controlled overcurrent protection and valve-controlled unbalance protection are designed using a "three-out-of-two" approach. As shown in Figure 1, the system includes a first valve protection unit 100, a second valve protection unit 110, a third valve protection unit 120, a first three-out-of-two protection unit 130, a second three-out-of-two protection unit 140, a first valve control unit 150, and a second valve control unit 160. The three valve protection units are independently configured in hardware. The first valve protection unit 100 samples the first measurement unit 170 to obtain sampled data, the second valve protection unit 110 samples the second measurement unit 180 to obtain sampled data, and the third valve protection unit 120 samples the third measurement unit 190 to obtain sampled data. After each valve protection unit evaluates the sampled data, it sends the processed data to the corresponding three-out-of-two protection unit for logical evaluation. The two three-out-of-two protection units are independent of each other and each sends the processed data to the corresponding valve control unit for unified processing within the valve control system. It should be noted that in the context, the valve protection unit and the overcurrent detection device both refer to the same product, and are uniformly expressed as the valve protection unit or the overcurrent detection device. Similarly, the three-out-of-two protection unit and the three-out-of-two protection device both refer to the same product, and are uniformly expressed as the three-out-of-two protection unit or the three-out-of-two protection device.

[0072] In traditional technology, early warning systems for new energy storage valve control systems have always considered vertical warnings, only considering the comparison between the protection setting value and the real-time analog value of a single overcurrent detection device, and not considering the comparison between the data of the overcurrent detection devices. Therefore, the early warning strategy for the valve control system is not comprehensive. Especially in the field of new energy storage ultra-high voltage, the reliability requirements of the valve control system are extremely strict. The inventors have discovered that adding horizontal warnings can enhance the ability of instantaneous value real-time warning, enhance the ability of multi-directional monitoring of bridge arm current, and enhance the system's panoramic fault monitoring and early warning capabilities, which is of great significance to improving the reliability and safety of the valve control system.

[0073] Therefore, this application proposes a technical solution for horizontally comparing the sampled data from multiple flow detection devices running in parallel in an energy storage valve control system. This technical solution is used in valve control systems in engineering integration applications of AC / DC microgrid / distribution network technology and battery energy storage technology. It uses horizontal data acquisition from overcurrent detection devices, compares data at the same time section, and issues an early warning when the difference between any two data points exceeds a threshold.

[0074] There are two technical solutions for horizontal warning proposed in this application: one is that N overcurrent detection devices share data in a ring network, with any overcurrent detection device as the master device. The master device performs a horizontal comparison of its own data with the data of other N-1 overcurrent detection devices to obtain a data difference. When the difference exceeds the corresponding threshold, the master device issues a warning signal; the other is that the data of N overcurrent detection devices are sent to the protection device, and the protection device performs a horizontal comparison of N data to obtain a data difference. When the data difference is greater than the corresponding threshold, the protection device issues a warning signal. Please refer to Figure 2, which is an application environment diagram of the overcurrent detection device according to some embodiments of the present application. Figure 2 shows an N-out-of-M redundant structure 200 as part of the energy storage valve control system, where N represents the number of overcurrent detection devices, which is an integer greater than or equal to 3, and M is an integer less than N. The N-out-M redundant structure 200 includes N overcurrent detection devices and one protection device. N overcurrent detection devices operate in parallel, including a first overcurrent detection device 210, a second overcurrent detection device 220, ..., and an Nth overcurrent detection device 230. The first overcurrent detection device 210 is adapted to sample a first measurement unit 250 to obtain a first current value, the second overcurrent detection device 220 is adapted to sample a second measurement unit 260 to obtain a second current value, ..., and the Nth overcurrent detection device 230 is adapted to sample an Nth measurement unit 270 to obtain an Nth current value. The protection device 240 is adapted to perform N-out-of-M voting on the overcurrent detection results output by the first overcurrent detection device 210 through the Nth overcurrent detection device 230 and output the N-out-of-M voting result.

[0075] Compared to the independent first, second, and third valve protection units 100, 110, and 120 shown in FIG1 , in this embodiment, any of the first through Nth overcurrent detection devices 210, 230 are communicatively connected to each of the other N-1 overcurrent detection devices. For example, each of the first through Nth overcurrent detection devices 210, 230 can share data such as real-time sampled current values ​​and sampling sequence numbers via the HSR (High-availability Seamless Redundancy) ring network protocol.

[0076] It is understood that the first overcurrent detection device 210 to the Nth overcurrent detection device 230 are overcurrent detection devices having the same configuration and performing the same function. Their different names are merely for ease of description. The structure of an overcurrent detection device according to an embodiment of the present application will be described below using the first overcurrent detection device 210 as an example in conjunction with FIG3 .

[0077] As shown in Figure 3, the first overcurrent detection device 210 includes a sampling unit 310, a transceiver unit 320, a difference calculation unit 330, and an early warning output unit 340. The sampling unit 310 is configured to sample the first measurement unit 250 to obtain a first current value. In some examples, the current is an instantaneous value. The transceiver unit 320 is configured to receive, from the other N-1 overcurrent detection devices, the second current value to the Nth current value obtained by each overcurrent detection device sampling the corresponding measurement unit, that is, to receive the second current value from the second overcurrent detection device 220, ..., and the Nth current value from the Nth overcurrent detection device 230. The transceiver unit 320 is also configured to send the first current value to the second overcurrent detection device 220 to the Nth overcurrent detection device 230, respectively. The difference calculation unit 330 is configured to calculate the current differences between the first current value and the second current value to the Nth current value, that is, to calculate the current difference between the first current value and the second current value to obtain the first current difference, to calculate the current difference between the first current value and the third current value to obtain the second current difference, and so on until the current difference between the first current value and the Nth current value is calculated to obtain the N-1th current difference. It should be noted that the first current difference to the N-1th current difference are all absolute values ​​of the instantaneous current difference. The warning output unit 340 is configured to output a first warning signal indicating that the first overcurrent detection device 210 is abnormal when the first current difference to the N-1th current difference are respectively greater than the first difference threshold to the N-1th difference threshold corresponding to the first current difference to the N-1th current difference.

[0078] In this embodiment, the first overcurrent detection device 210 can be considered a master overcurrent detection device, while the second through Nth overcurrent detection devices 220 through 230 can be considered slave overcurrent detection devices. The master overcurrent detection device receives the current values ​​of the other N-1 slave overcurrent detection devices via the transceiver unit 320, calculates the current difference between the master overcurrent detection device and the N-1 slave overcurrent detection devices via the difference calculation unit 330, and issues an abnormality warning to the master overcurrent detection device via the warning output unit 340 when all the calculated N-1 current differences exceed the corresponding difference thresholds, thereby improving the reliability and safety of the valve control system.

[0079] In some embodiments, the difference calculation unit 330 is configured to respectively calculate the current difference between the Kth current value from the second current value to the Nth current value and the remaining current values ​​from the second current value to the Nth current value. The warning output unit 340 is configured to output a second warning signal indicating that the Kth overcurrent detection device that samples the Kth current value is abnormal when only one current difference from the first current difference to the N-1th current difference is greater than the corresponding difference threshold, for example, when only the K-1th current difference between the first current value and the Kth current value is greater than the K-1th difference threshold, while the remaining N-2 current differences from the first current difference to the N-1th current difference are all less than or equal to the corresponding difference threshold, and each current difference between the Kth current value and the remaining current values ​​from the second current value to the Nth current value is greater than the corresponding difference threshold.

[0080] The above-mentioned warning output unit 340 can not only realize abnormal warning for the first overcurrent detection device 210, but also realize abnormal warning for the other N-1 overcurrent detection devices.

[0081] In some embodiments, the time sections can be arranged according to the sampling period within a predetermined time period. As shown in Figure 4, the first overcurrent detection device 210 may further include a storage unit 350 and a difference threshold value calculation unit 360. The storage unit 350 is configured to store the first current value to the Nth current value associated with the sampling sequence number at each time section. The difference threshold value calculation unit 360 is configured to enable the current rating when receiving the setting of the current rating of the energy storage valve control system operation. The setting of the current rating can be set manually. Further, the first current value to the Nth current value stored at each time section are compared with the preset current range. If each of the first current value to the Nth current value is within the preset current range, it is confirmed that the current first current value to the Nth current value can be used for the calculation of the difference threshold value. The preset current range is determined according to the set current rating. In some examples, I n Taking the rated current as an example, the preset current range can be (1±20%)I n Furthermore, the difference threshold value calculation unit 360 calculates the first difference threshold value to the N-1th difference threshold value based on the multiple first current values ​​to the Nth current values ​​at the multiple time sections, and calculates the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value.

[0082] The storage unit 350 is further configured to store the first to N-1th difference thresholds, and store the difference thresholds of the Kth current value relative to the remaining current values ​​from the second to Nth current values.

[0083] By dynamically calculating and updating the difference threshold value in real time through the difference threshold value calculation unit 360 , an overcurrent detection device having abnormal sampling values ​​relative to other overcurrent detection devices can be found more accurately.

[0084] In some embodiments, the difference calculation unit 330 performs a horizontal comparison of the sampling numbers under the same time section to obtain the sampling number differences between any two of the N overcurrent detection devices. Further, based on the corresponding sampling number differences, the first current difference between the first current value and the second current value, the second current difference between the first current value and the third current value,..., the N-1th current difference between the first current value and the Nth current value, and the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value are calculated respectively. The same calculation is performed for other time sections.

[0085] The difference calculation unit 330 calculates the first current difference to the N-1th current difference under multiple time sections, so that the difference threshold calculation unit 360 can correspondingly obtain more reliable and accurate first difference threshold, second difference threshold and third difference threshold.

[0086] In some embodiments, the difference calculation unit 330 averages each of the first to N-1th current differences at different time intervals to obtain the first to N-1th typical difference values. Furthermore, the difference calculation unit 330 averages each of the current differences between the Kth current value and the remaining current values ​​from the second to Nth current values ​​at different time intervals to obtain the respective typical difference values ​​of the Kth current value relative to the remaining current values ​​from the second to Nth current values. When calculating the typical difference values, the number of selected time intervals can be set based on actual conditions. In some examples, the current differences from the first to N-1th current differences at 10 time intervals can be used for the calculation.

[0087] The difference threshold value calculation unit 360 obtains a preset threshold coefficient and then multiplies each typical difference value by the preset threshold coefficient to determine the corresponding difference threshold value. Specifically, the preset threshold coefficient can be manually set according to actual needs and its value is greater than 1. In some examples, a typical value of the threshold coefficient is 1.2.

[0088] To more specifically illustrate the technical solution of the overcurrent detection device of the present application, the following describes the technical solution of the present application in detail, taking the N-out-of-M redundant structure 200 in FIG. 2 as an example of a 2-out-of-3 redundant structure. It will be understood that when the N-out-of-M redundant structure is a 2-out-of-3 redundant structure, the protection device will execute a 2-out-of-3 logic for the overcurrent detection result.

[0089] Please refer to Figure 5, which illustrates an application environment for overcurrent detection devices according to other embodiments of the present application. Figure 5 illustrates a two-out-of-three redundant structure 500 as part of an energy storage valve control system. The two-out-of-three redundant structure 500 includes three overcurrent detection devices and a two-out-of-three protection device 540. The three overcurrent detection devices operate in parallel and include a first overcurrent detection device 510, a second overcurrent detection device 520, and a third overcurrent detection device 530. The first overcurrent detection device 510 is configured to sample a first measurement unit 550 to obtain a first current value, the second overcurrent detection device 520 is configured to sample a second measurement unit 560 to obtain a second current value, and the third overcurrent detection device 530 is configured to sample a third measurement unit 570 to obtain a third current value. The two-out-of-three protection device 540 is configured to perform a two-out-of-three vote on the overcurrent detection results output by the first, second, and third overcurrent detection devices 510, 520, and 530, and output the two-out-of-three vote result.

[0090] In this embodiment, any one of the first overcurrent detection device 510, the second overcurrent detection device 520, and the third overcurrent detection device 530 is communicatively connected to the other two overcurrent detection devices. For example, the first overcurrent detection device 510, the second overcurrent detection device 520, and the third overcurrent detection device 530 can share data such as real-time sampled current values ​​and sampling sequence numbers via the HSR ring network protocol.

[0091] The structure of the overcurrent detection device according to the embodiment of the present application is described below by taking the first overcurrent detection device 510 as an example in conjunction with FIG6 .

[0092] As shown in FIG6 , the first overcurrent detection device 510 includes a sampling unit 610, a transceiver unit 620, a difference calculation unit 630, an early warning output unit 640, and a storage unit 650. The sampling unit 610 is configured to sample the first measurement unit 550 to obtain a first current value. In some examples, the current is an instantaneous value. The transceiver unit 620 is configured to receive a second current value from the second overcurrent detection device 520 and a third current value from the third overcurrent detection device 530. The transceiver unit 620 is also configured to transmit the first current value to the second overcurrent detection device 520 and the third overcurrent detection device 530. The difference calculation unit 630 is configured to calculate a first current difference between the first current value and the second current value, and a second current difference between the first current value and the third current value. The first current difference may be the absolute value of the current difference between the first current value and the second current value, and the second current difference may be the absolute value of the current difference between the first current value and the third current value. The warning output unit 640 is configured to output a first warning signal indicating that the first overcurrent detection device is abnormal when the first current difference is greater than a first difference threshold value and the second current difference is greater than a second difference threshold value. The storage unit 650 is configured to store the first current value, the second current value, and the third current value.

[0093] In this embodiment, the first overcurrent detection device 510 can be considered a master overcurrent detection device, while the second overcurrent detection device 520 and the third overcurrent detection device 530 can be considered slave overcurrent detection devices. The master overcurrent detection device receives the current values ​​of the two slave overcurrent detection devices respectively via the transceiver unit 620, calculates the current difference between the master overcurrent detection device and the two slave overcurrent detection devices via the difference calculation unit 630, and issues an abnormality warning to the master overcurrent detection device via the warning output unit 640 when both calculated current differences exceed corresponding difference thresholds, thereby improving the reliability and safety of the valve control system.

[0094] In some embodiments, the difference calculation unit 630 is configured to calculate the absolute value of the current difference between the second current value and the third current value to obtain the third current difference. The warning output unit 640 is configured to output a second warning signal indicating an abnormality in the second overcurrent detection device 520 or a third warning signal indicating an abnormality in the third overcurrent detection device 530 based on a comparison relationship between the third current difference and the third difference threshold when only one of the first current difference and the second current difference is greater than the difference threshold.

[0095] The above-mentioned warning output unit 640 can not only realize abnormal warning of the first overcurrent detection device, but also realize abnormal warning of the other two overcurrent detection devices.

[0096] In some embodiments, the time sections may be arranged according to the sampling period within a predetermined time period. The storage unit 650 is configured to store the first current value, the second current value, and the third current value associated with the sampling sequence number in each time section.

[0097] As shown in FIG7 , the first overcurrent detection device 510 may further include a difference threshold value calculation unit 660. Upon receiving the setting of the current rating value for the operation of the energy storage valve control system, the difference threshold value calculation unit 660 enables the current rating value. Furthermore, the first current value, the second current value, and the third current value stored at each time section are compared with a preset current range. If the first current value, the second current value, and the third current value are all within the preset current range, it is confirmed that the current first current value, the second current value, and the third current value can be used for calculating the difference threshold value. Furthermore, the difference threshold value calculation unit 660 calculates the first difference threshold value, the second difference threshold value, and the third difference threshold value based on multiple first current values, multiple second current values, and multiple third current values ​​at multiple time sections.

[0098] The storage unit 650 is further configured to store a first difference threshold value, a second difference threshold value, and a third difference threshold value.

[0099] By dynamically calculating and updating the difference threshold value in real time through the difference threshold value calculation unit 660 , an overcurrent detection device having abnormal sampling values ​​relative to other overcurrent detection devices can be found more accurately.

[0100] In some embodiments, the difference calculation unit 630 performs a horizontal comparison of the sampling numbers under the same time section to obtain the sampling number differences between any two of the three overcurrent detection devices. Further, based on the corresponding sampling number differences, the first current difference between the first current value and the second current value, the second current difference between the first current value and the third current value, and the third current difference between the second current value and the third current value are calculated respectively. The same calculation is performed for other time sections.

[0101] The difference threshold value calculation unit 660 calculates a first difference threshold value, a second difference threshold value, and a third difference threshold value based on the first current difference value, the second current difference value, and the third current difference value in each time section, respectively.

[0102] The difference calculation unit 630 calculates the first current difference, the second current difference and the third current difference under multiple time sections, so that the difference threshold calculation unit 360 can correspondingly obtain more reliable and accurate first difference threshold, second difference threshold and third difference threshold.

[0103] In some embodiments, the difference calculation unit 630 averages the first current difference, the second current difference, and the third current difference at different time intervals to obtain a first typical difference value, a second typical difference value, and a third typical difference value. When calculating the typical difference value, the number of selected time intervals can be set according to actual conditions. In some examples, the first current difference, the second current difference, and the third current difference at 10 time intervals can be used for the calculation.

[0104] The difference threshold value calculation unit 660 determines a first difference threshold value, a second difference threshold value, and a third difference threshold value based on the first difference typical value, the second difference typical value, and the third difference typical value.

[0105] In some embodiments, the difference threshold value calculation unit 660 obtains a preset threshold coefficient and then multiplies each difference typical value by the preset threshold coefficient to determine the corresponding difference threshold value.

[0106] In some embodiments, as shown in FIG8 , an abnormality warning method is provided. This embodiment uses the method applied to the N-out-of-M redundant structure 200 in the energy storage valve control system shown in FIG2 as an example for illustration.

[0107] The method is performed by any one of the first overcurrent detection device 210, the second overcurrent detection device 220, to the Nth overcurrent detection device 230. When the method is performed by the first overcurrent detection device 210, the method includes:

[0108] In step S110 , the second current value to the Nth current value are received from the second overcurrent detection device 220 to the Nth overcurrent detection device 230 , respectively.

[0109] In step S120 , a first current difference to an N−1th current difference are calculated, where the first current difference to the N−1th current difference represent current differences between the first current value and the second current value to the Nth current value.

[0110] Specifically, the first current difference is the difference between the first current value and the second current value, the second current difference is the difference between the first current value and the third current value, and so on. The N-1th current difference is the difference between the first current value and the Nth current value.

[0111] In step S130 , when the first current difference to the N−1th current difference are respectively greater than the first difference threshold to the N−1th difference threshold corresponding to the first current difference to the N−1th current difference, a first warning signal is output, and the first warning signal indicates that the first overcurrent detection device 210 is abnormal.

[0112] Specifically, the first current difference and the first difference threshold value, the second current difference and the second difference threshold value, ..., the N-1th current difference and the N-1th difference threshold value are compared respectively. When each of the first current difference to the N-1th current difference is greater than the corresponding difference threshold value, it is determined that the first overcurrent detection device 210 is abnormal, and a first warning signal is output and sent to the monitoring background to realize real-time warning.

[0113] In this implementation, any overcurrent detection device serves as the master device. The master device then transversely receives current values ​​from N-1 other overcurrent detection devices. The master device then determines the current differences between the master device and the other N-1 overcurrent detection devices. These N-1 current differences are then compared with corresponding difference thresholds. When all N-1 current differences exceed the corresponding difference thresholds, an abnormality warning is issued to the master overcurrent detection device. This enables transverse warnings by comparing sampled data between the overcurrent detection devices, improving the reliability and safety of the valve control system.

[0114] In some embodiments, as shown in FIG9 , the method further includes:

[0115] In step S140 , current differences between the Kth current value from the second current value to the Nth current value and the remaining current values ​​from the second current value to the Nth current value are calculated respectively.

[0116] Specifically, the current difference between the Kth current value and the second current value, the current difference between the Kth current value and the third current value, and so on are calculated respectively until the current difference between the Kth current value and the Nth current value is calculated.

[0117] Step S150, when the K-1th current difference among the first current difference to the N-1th current difference is greater than the K-1th difference threshold value, the remaining N-2 current differences are less than or equal to the corresponding difference threshold values, and the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value are respectively greater than the corresponding difference threshold values, a second warning signal is output, and the second warning signal indicates that the Kth overcurrent detection device is abnormal.

[0118] Specifically, when the K-1th current difference between the first current value and the Kth current value is greater than the K-1th difference threshold value, and the remaining N-2 current differences from the first current difference to the N-1th current difference are less than or equal to the corresponding difference threshold value, and each current difference between the Kth current value and the remaining current values ​​from the second current value to the Nth current value is greater than the corresponding difference threshold value, a second warning signal indicating that the Kth overcurrent detection device is abnormal is output.

[0119] In this embodiment, when the current difference between any overcurrent detection device and only one other overcurrent detection device is greater than the corresponding difference threshold value, the current difference between the other N-1 overcurrent detection devices is compared with the corresponding difference threshold value, thereby achieving abnormal warning for the other N-1 overcurrent detection devices.

[0120] In some embodiments, time sections can be arranged according to the sampling period within a predetermined time period, and the first current value to the Nth current value associated with the sampling sequence number can be stored in each time section. Furthermore, multiple first current values ​​to the Nth current values ​​in multiple time sections can be stored.

[0121] When the first overcurrent detection device 210 receives the current rating setting for the energy storage valve control system, it enables the current rating. Furthermore, the first to Nth current values ​​stored in each time segment are compared with a preset current range. If each of the first to Nth current values ​​is within the preset current range, the current first to Nth current values ​​are confirmed to be applicable to the calculation of the difference threshold.

[0122] Compared with using a pre-set value or a value manually set based on historical data as the difference threshold value between overcurrent detection devices, the embodiment of the present application dynamically calculates and updates the difference threshold value in real time, which can more accurately find the overcurrent detection device with abnormal sampling values ​​relative to other overcurrent detection devices.

[0123] In some embodiments, the steps of calculating the first difference threshold value to the N-1th difference threshold value, and calculating the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value include: performing a horizontal comparison of the sampling numbers under the same time section to obtain the sampling number differences between any two of the N overcurrent detection devices, and further, according to the corresponding sampling number differences, respectively calculating the first current difference to the N-1th current difference between the first current value and the second current value to the Nth current value, and calculating the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value, and the same calculation is performed under other time sections.

[0124] Furthermore, based on the first current difference to the N-1th current difference at different time sections, the first difference threshold to the N-1th difference threshold are calculated; and based on the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at different time sections, the difference thresholds of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value are calculated.

[0125] In some embodiments, the steps of processing the first current difference value to the N-1th current difference value at each time section respectively to obtain the first difference threshold value to the N-1th difference threshold value include: respectively calculating the average value of each of the multiple first current difference values ​​to the multiple N-1th current difference values ​​at multiple time sections, and correspondingly obtaining the first difference typical value to the N-1th difference typical value; further, multiplying each of the first difference typical value to the N-1th difference typical value by a preset threshold coefficient to obtain the first difference threshold value to the N-1th difference threshold value.

[0126] The step of calculating the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value based on the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at each time section includes: calculating the average values ​​of the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at multiple time sections in a one-to-one correspondence, obtaining typical values ​​of the differences of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value, and further multiplying the typical values ​​of the differences of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value by a preset threshold coefficient to obtain the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value.

[0127] In other embodiments, as shown in FIG10 , an abnormality warning method is provided. This embodiment uses the method applied to the two-out-of-three redundant structure 500 in the energy storage valve control system shown in FIG5 as an example for illustration.

[0128] The method is performed by any one of the first overcurrent detection device 510, the second overcurrent detection device 520, and the third overcurrent detection device 530. When the method is performed by the first overcurrent detection device 510, the method includes:

[0129] In step S210 , a second current value and a third current value are received from the second overcurrent detection device 520 and the third overcurrent detection device 530 respectively.

[0130] Specifically, the first overcurrent detection device 510 can receive in real time the second current value sent by the second overcurrent detection device 520 and the third current value sent by the third overcurrent detection device 530 at the same time segment. In some examples, the first current value, the second current value, and the third current value are all instantaneous current values.

[0131] Step S220, calculating a first current difference between the first current value and the second current value; calculating a second current difference between the first current value and the third current value;

[0132] Specifically, the first current difference is the absolute value of the instantaneous current difference between the first overcurrent detection device 510 and the second overcurrent detection device 520 , and the second current difference is the absolute value of the instantaneous current difference between the first overcurrent detection device 510 and the third overcurrent detection device 530 .

[0133] Step S230 : When the first current difference is greater than the first difference threshold and the second current difference is greater than the second difference threshold, a first warning signal is output, indicating that the first overcurrent detection device 510 is abnormal.

[0134] Specifically, the first difference threshold is a current difference threshold between the first overcurrent detection device 510 and the second overcurrent detection device 520, and the second difference threshold is a current difference threshold between the first overcurrent detection device 510 and the third overcurrent detection device 530. The first current difference between the first overcurrent detection device 510 and the second overcurrent detection device 520 is compared with the corresponding first difference threshold, and the second current difference between the first overcurrent detection device 510 and the third overcurrent detection device 530 is compared with the corresponding second difference threshold. Based on the comparison results, an abnormal overcurrent detection device can be detected.

[0135] When the first current difference is greater than the first difference threshold value and the second current difference is greater than the second difference threshold value, it is determined that the first overcurrent detection device 510 is abnormal, and a first warning signal is output and sent to the monitoring background to achieve real-time warning.

[0136] In this implementation, any one overcurrent detection device serves as the master device. The master device then transversely receives the current values ​​of the other two overcurrent detection devices, obtaining the current differences between the master device and the other two devices. These current differences are then compared with corresponding difference thresholds. When both current differences exceed the corresponding difference thresholds, an abnormality warning is issued to the master overcurrent detection device. This enables transverse warnings by comparing sampled data between the overcurrent detection devices, improving the reliability and safety of the valve control system.

[0137] In some embodiments, as shown in FIG11 , the method further includes:

[0138] Step S240 , calculating a third current difference between the second current value and the third current value.

[0139] Specifically, the third current difference is the absolute value of the instantaneous current difference between the second overcurrent detection device 520 and the third overcurrent detection device 530 .

[0140] Step S250: When the first current difference is greater than the first difference threshold, the second current difference is less than or equal to the second difference threshold, and the third current difference is greater than the third difference threshold, a second warning signal is output, indicating that the second overcurrent detection device 520 is abnormal.

[0141] Specifically, the third difference threshold is a current difference threshold between the second overcurrent detection device 520 and the third overcurrent detection device 530. When the first current difference is greater than the first difference threshold, and the second current difference is less than or equal to the second difference threshold, the third current difference between the second overcurrent detection device 520 and the third overcurrent detection device 530 is further compared with the corresponding third difference threshold. When the third current difference is greater than the third difference threshold, it is determined that the second overcurrent detection device 520 is abnormal, and a second warning signal is output, indicating that the second overcurrent detection device 520 is abnormal.

[0142] In step S260, when the first current difference is less than or equal to the first difference threshold, the second current difference is greater than the second difference threshold, and the third current difference is greater than the third difference threshold, a third warning signal is output, indicating that the third overcurrent detection device 530 is abnormal.

[0143] Specifically, when the first current difference is less than or equal to the first difference threshold value and the second current difference is greater than the second difference threshold value, the third current difference between the third overcurrent detection device 530 and the second overcurrent detection device 520 is further compared with the corresponding third difference threshold value. When the third current difference is greater than the third difference threshold value, it is determined that the third overcurrent detection device 530 is abnormal, and a third early warning signal is output, which indicates that the third overcurrent detection device 530 is abnormal.

[0144] By comparing the current difference between any one overcurrent detection device and only one other overcurrent detection device with the corresponding difference threshold value when the current difference is greater than the corresponding difference threshold value, the current difference between the other two overcurrent detection devices is compared with the corresponding difference threshold value, thereby achieving abnormal warning for the other two overcurrent detection devices when any one overcurrent detection device is used as the main device.

[0145] The above three overcurrent detection devices all adopt asynchronous sampling mode. There are differences in the crystal oscillator and power-on time of each overcurrent detection device. Therefore, at the same time section, the message sequence number sent by each device will be different, that is, the sampling sequence number difference. Under normal circumstances, the deviation between the sampling sequence numbers at different time sections remains unchanged.

[0146] In some embodiments, time sections can be arranged according to the sampling period within a predetermined time period, and the first current value, second current value, and third current value associated with the sampling sequence number can be stored in each time section. Furthermore, multiple first current values, multiple second current values, and multiple third current values ​​in multiple time sections can be stored. In some examples, when the corresponding sampling sequence point cannot be found based on the sampling sequence number deviation value, the information is sent to the monitoring backend after identification to achieve real-time warning.

[0147] When the first overcurrent detection device 510 receives the setting of the current rating value for the operation of the energy storage valve control system, the current rating value is enabled. The current rating value setting can be set manually. Furthermore, the first current value, the second current value, and the third current value stored in each time section are compared with the preset current range. If the first current value, the second current value, and the third current value are all within the preset current range, it is confirmed that the current first current value, the second current value, and the third current value can be used to calculate the difference threshold value.

[0148] In some embodiments, the step of calculating the first difference threshold value, the second difference threshold value, and the third difference threshold value includes: performing a horizontal comparison of the sampling sequence numbers under the same time section to obtain the sampling sequence number difference between any two of the three overcurrent detection devices, as shown in FIG12, which provides a schematic diagram of the correspondence between the sampling sequence numbers and the sampling data of the overcurrent detection devices, where △n1 represents the sampling sequence number difference between the first sampling sequence number corresponding to the first overcurrent detection device 510 and the second sampling sequence number corresponding to the second overcurrent detection device 520, and △n2 represents the sampling sequence number difference between the second overcurrent detection device 520. The sampling number difference between the corresponding second sampling number and the third sampling number corresponding to the third overcurrent detection device 530 is calculated. Δn3 represents the sampling number difference between the first sampling number corresponding to the first overcurrent detection device 510 and the third sampling number corresponding to the third overcurrent detection device 530. Furthermore, based on the corresponding sampling number differences, a first current difference Δ1 between the first current value and the second current value, a second current difference Δ2 between the first current value and the third current value, and a third current difference Δ3 between the second current value and the third current value are calculated. The same calculations are performed for other time sections. Furthermore, the first current difference, the second current difference, and the third current difference at each time section are processed to obtain a first difference threshold, a second difference threshold, and a third difference threshold.

[0149] By accumulating the first current difference, the second current difference and the third current difference at multiple time sections, more reliable first difference threshold, second difference threshold and third difference threshold can be obtained accordingly.

[0150] In some embodiments, the first current difference, the second current difference and the third current difference at each time section are processed respectively to obtain the first difference threshold value, the second difference threshold value and the third difference threshold value, and the steps include: taking the average value of the first current difference, the second current difference and the third current difference at different time sections respectively, and obtaining the first difference typical value, the second difference typical value and the third difference typical value accordingly, thereby determining the corresponding difference threshold values ​​according to the respective difference typical values.

[0151] In some embodiments, based on the first difference typical value, the second difference typical value and the third difference typical value, the step of determining the first difference threshold value, the second difference threshold value and the third difference threshold value includes: multiplying each difference typical value by a preset threshold coefficient to determine the corresponding difference threshold value.

[0152] After each difference threshold value is determined, it is written into the flash and is not lost during power failure. The difference threshold values ​​are only updated when the enable command of the current rating is updated.

[0153] By adding a preset threshold coefficient to each typical difference value, a relatively accurate difference threshold value can be obtained, thereby improving the reliability of each difference threshold value.

[0154] When the three overcurrent detection devices in the three-out-of-two redundant structure 500 simultaneously execute the above-mentioned abnormal warning method, all warnings will adopt instantaneous alarm and delayed return strategies. The delay time can be set according to actual needs. In some examples, it is generally set to the time interval between three sampling data of the three overcurrent detection devices. The purpose of delayed return is to avoid fluctuations in sampling data, repeated alarms and increase the load on the CPU inside the device.

[0155] The above-mentioned abnormal warning method realizes real-time warning of abnormal overcurrent detection devices by sharing horizontal data among the three overcurrent detection devices, and then any overcurrent detection device compares the horizontal data. Compared with the traditional technology that only relies on vertical data comparison in the valve control system for warning, this application makes the warning strategy in the new energy storage valve control system more perfect, enhances the reliability of the system, and improves the fault monitoring and warning capabilities.

[0156] Please refer to Figure 13, which illustrates an application environment for protection devices according to some embodiments of the present application. Figure 13 illustrates a 2xN-out-of-M redundant architecture 700 as part of an energy storage valve control system, where N represents the number of overcurrent detection devices, which is an integer greater than or equal to 3, and M is an integer less than N. 2xN-out-of-M redundant architecture 700 includes N overcurrent detection devices and two protection devices. The N overcurrent detection devices operate in parallel, including a first overcurrent detection device 710, a second overcurrent detection device 720, ..., and an Nth overcurrent detection device 730. The two protection devices operate in parallel, including a first protection device 770 and a second protection device 780. The first overcurrent detection device 710 is configured to sample a first measurement unit 740 to obtain a first current value, the second overcurrent detection device 720 is configured to sample a second measurement unit 750 to obtain a second current value, and so on, with the Nth overcurrent detection device 730 being configured to sample an Nth measurement unit 760 to obtain an Nth current value. Each of the two protection devices performs an N-out-of-M voting on the overcurrent detection results output by the first overcurrent detection device 710 through the Nth overcurrent detection device 730 and outputs the N-out-of-M voting result. The two protection devices are communicatively connected to each other. It can be understood that the two-by-N-out-of-M redundancy structure 700 can be considered to include two N-out-of-M redundancy structures as described above, wherein the two N-out-of-M redundancy structures reuse N overcurrent detection devices.

[0157] It is understood that the first protection device 770 and the second protection device 780 are protection devices having the same configuration and performing the same function, and that they are named differently for ease of description. The structure of the protection device according to an embodiment of the present application will be described below using the first protection device 770 as an example in conjunction with FIG14 .

[0158] As shown in FIG14 , the first protection device 770 may include a receiving unit 810, a difference calculation unit 820, and an early warning output unit 830. The receiving unit 810 is configured to receive, at the same time interval, the first current value of the first overcurrent detection device 710, the second current value of the second overcurrent detection device 720, and so on, the Nth current value of the Nth overcurrent detection device 730. The difference calculation unit 820 is configured to calculate the current difference between the first current value and the second current value to obtain a first current difference value, and to calculate the current difference between the first current value and the third current value to obtain a second current difference value. Similarly, the current difference between the first current value and the Nth current value is calculated to obtain an N-1th current difference value. The early warning output unit 830 is configured to output a first early warning signal indicating an abnormality in the first overcurrent detection device 710 when each of the first to N-1th current differences is greater than the corresponding first to N-1th difference thresholds.

[0159] The above-mentioned protection device receives the current values ​​of N overcurrent detection devices respectively through the receiving unit 810, and then obtains the first current difference to the N-1th current difference of the first current value and the other N-1 current values ​​respectively through the difference calculation unit 820 based on the first current value, so as to compare the first current difference to the N-1th current difference with the corresponding difference threshold value respectively through the early warning output unit 830, and when these N-1 current differences all exceed the corresponding difference threshold value, an abnormal early warning of the first overcurrent detection device 710 is realized.

[0160] The functional definition of each structural unit in the protection device in the following embodiments is similar to the functional definition of the corresponding structural unit in the first overcurrent detection device 210 described above, and will not be repeated here.

[0161] In some embodiments, the difference calculation unit 820 is configured to respectively calculate the current difference between the Kth current value from the second current value to the Nth current value and the remaining current values ​​from the second current value to the Nth current value. The warning output unit is configured to output a second warning signal when the K-1th current difference from the first current difference to the N-1th current difference is greater than the K-1th difference threshold, the remaining N-2 current differences are less than or equal to the corresponding difference thresholds, and the current difference between the Kth current value and the remaining current values ​​from the second current value to the Nth current value is greater than the corresponding difference threshold, indicating that the Kth overcurrent detection device is abnormal.

[0162] When only one current difference value among the first current difference value to the N-1th current difference value is greater than the difference threshold value, for example, when only the K-1th current difference value is greater than the K-1th difference threshold value, the early warning output unit 830 compares the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value with the corresponding difference threshold values, thereby realizing an abnormal early warning of the second overcurrent detection device 720 to the Nth overcurrent detection device 730.

[0163] In some embodiments, as shown in FIG15 , the first protection device 770 further includes a storage unit 840 and a difference threshold value calculation unit 850. The storage unit 840 includes N buffers, each of which stores the received first to Nth current values. In addition, the storage unit 840 may also store, for example, sampling numbers of each overcurrent detection device. The storage unit 840 is configured to store the plurality of first to Nth current values ​​in association with the sampling numbers within a predetermined time period including multiple time slices. The difference threshold value calculation unit 850 is configured to calculate, based on the plurality of stored first to Nth current values, a first to N-1th difference threshold values, and to calculate the difference threshold values ​​for the Kth current value relative to the remaining current values ​​from the second to Nth current values, when each current value from the plurality of stored first to Nth current values ​​is within a preset current range. The storage unit 840 is further configured to store all difference threshold values.

[0164] In some embodiments, the difference calculation unit 820 is configured to calculate the first current difference to the N-1th current difference between the stored first current value and the stored second current value to the Nth current value according to the corresponding sampling sequence number at each time section within a predetermined time period, and to calculate the current differences between the Kth current value among the stored second current value to the Nth current value and the remaining current values ​​among the second current value to the Nth current value.

[0165] The difference threshold value calculation unit 850 is configured to calculate the first difference threshold value to the N-1th difference threshold value based on the first current difference value to the N-1th current difference value at each time section, respectively; and to calculate the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value based on the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at each time section, respectively.

[0166] In some embodiments, the difference calculation unit 820 is configured to calculate the average value of each of the multiple first current difference values ​​to the multiple N-1th current difference values ​​under multiple time sections to obtain the first difference typical value to the N-1th difference typical value; respectively calculate the average values ​​of each current difference between the Kth current value and the remaining current values ​​from the second current value to the Nth current value under multiple time sections to obtain the typical values ​​of the differences of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value.

[0167] The difference threshold value calculation unit 850 is configured to respectively calculate the product of the first difference typical value to the N-1th difference typical value and the preset threshold coefficient to obtain the first difference threshold value to the N-1th difference threshold value; and respectively calculate the product of each difference typical value of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value and the preset threshold coefficient to obtain each difference threshold value of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value.

[0168] In order to more specifically illustrate the technical solution of the protection device of the present application, the technical solution of the present application is described in detail below by taking the two-by-N-take-M redundant structure 700 in Figure 13 as a two-by-three-take-two redundant structure and the protection device as a three-take-two protection device as an example.

[0169] Please refer to Figure 16, which is an application environment diagram of a three-out-of-two protection device according to other embodiments of the present application. Figure 16 shows a two-by-three-out-of-two redundant structure 900 as part of an energy storage valve control system. The two-by-three-out-of-two redundant structure 900 includes three overcurrent detection devices and two three-out-of-two protection devices. The three overcurrent detection devices operate in parallel, including a first overcurrent detection device 910, a second overcurrent detection device 920, and a third overcurrent detection device 930. The two three-out-of-two protection devices operate in parallel, including a first three-out-of-two protection device 970 and a second three-out-of-two protection device 980. The first overcurrent detection device 910 is suitable for sampling the first measurement unit 940 to obtain a first current value, the second overcurrent detection device 920 is suitable for sampling the second measurement unit 950 to obtain a second current value, and the third overcurrent detection device 930 is suitable for sampling the third measurement unit 960 to obtain a third current value. Each of the two 2-out-of-3 protection devices performs a 2-out-of-3 vote on the overcurrent detection results output by the first overcurrent detection device 910, the second overcurrent detection device 920, and the third overcurrent detection device 930, and outputs the 2-out-of-3 voting result. The two 2-out-of-3 protection devices are communicatively connected to each other. It can be understood that the 2x2-out-of-3 redundant structure 900 can be considered to include two 2-out-of-3 redundant structures as described above, wherein the two 2-out-of-3 redundant structures reuse three overcurrent detection devices.

[0170] The structure of the two-out-of-three protection device according to the embodiment of the present application is described below by taking the first two-out-of-three protection device 970 as an example in conjunction with FIG17 .

[0171] As shown in Figure 17, the first two-out-of-three protection device 970 may include a receiving unit 901, a difference calculation unit 902, an early warning output unit 903, and a storage unit 904. The receiving unit 901 is configured to receive, at the same time interval, the first current value of the first overcurrent detection device 910, the second current value of the second overcurrent detection device 920, and the third current value of the third overcurrent detection device 930. The storage unit 904 includes three buffers, each of which stores the received first current value, second current value, and third current value. In addition, the storage unit 904 may also store, for example, the sampling sequence number of each overcurrent detection device.

[0172] The difference calculation unit 902 is configured to calculate the absolute value of the current difference between the first current value and the second current value to obtain a first current difference, and calculate the absolute value of the current difference between the first current value and the third current value to obtain a second current difference.

[0173] The warning output unit 903 is configured to output a first warning signal indicating that the first overcurrent detection device 910 is abnormal when the first current difference is greater than a first difference threshold and the second current difference is greater than a second difference threshold.

[0174] The above-mentioned three-out-of-two protection device receives the current values ​​of the three overcurrent detection devices respectively through the receiving unit 901, and then obtains the first current difference and the second current difference between the first current value and the other two sampling values ​​respectively based on the first current value through the difference calculation unit 902, so as to compare the first current difference and the second current difference with the corresponding difference threshold values ​​respectively through the early warning output unit 903, and realizes an abnormal early warning for the first overcurrent detection device 910 when both current differences exceed the corresponding difference threshold values.

[0175] The functional definition of each structural unit in the two-out-of-three protection device in the following embodiments is similar to the functional definition of the corresponding structural unit in the first overcurrent detection device 510 described above, and will not be repeated here.

[0176] In some embodiments, the difference calculation unit 902 is configured to calculate a third current difference between the second current value and the third current value.

[0177] The early warning output unit 903 is configured to output a second early warning signal when the first current difference is greater than the first difference threshold value, the second current difference is less than or equal to the second difference threshold value, and the third current difference is greater than the third difference threshold value, and the second early warning signal indicates that the second overcurrent detection device 920 is abnormal; and is also configured to output a third early warning signal when the first current difference is less than or equal to the first difference threshold value, the second current difference is greater than the second difference threshold value, and the third current difference is greater than the third difference threshold value, and the third early warning signal indicates that the third overcurrent detection device 930 is abnormal.

[0178] When only one of the first current difference and the second current difference is greater than the difference threshold, the warning output unit 903 compares the third current difference with the third difference threshold to provide an abnormal warning for the second overcurrent detection device 920 and the third overcurrent detection device 930.

[0179] In some embodiments, the storage unit 904 is configured to store a plurality of first current values, a plurality of second current values, and a plurality of third current values ​​in association with sampling sequence numbers within a predetermined time period.

[0180] As shown in Figure 18, the first three-to-two protection device 970 also includes a difference threshold value calculation unit 905, which is configured to calculate the first difference threshold value, the second difference threshold value and the third difference threshold value based on the stored multiple first current values, the multiple second current values ​​and the multiple third current values ​​when each current value of the stored multiple first current values, the multiple second current values ​​and the multiple third current values ​​is within a preset current range.

[0181] The storage unit 904 is configured to store a first difference threshold value, a second difference threshold value, and a third difference threshold value.

[0182] In some embodiments, the difference calculation unit 902 is configured to calculate, at each time section within a predetermined time period, a first current difference between the first current value and the second current value, a second current difference between the first current value and the third current value, and a third current difference between the second current value and the third current value according to the corresponding sampling sequence number;

[0183] The difference threshold value calculation unit 905 is configured to calculate a first difference threshold value, a second difference threshold value, and a third difference threshold value based on the first current difference value, the second current difference value, and the third current difference value at each time section, respectively.

[0184] In some embodiments, the difference calculation unit 902 is configured to calculate an average value of a plurality of first current differences at a plurality of time sections to obtain a first difference typical value; calculate an average value of a plurality of second current differences at a plurality of time sections to obtain a second difference typical value; and calculate an average value of a plurality of third current differences at a plurality of time sections to obtain a third difference typical value;

[0185] The difference threshold value calculation unit 905 is configured to calculate the product of the first difference typical value and the preset threshold coefficient to obtain the first difference threshold value; calculate the product of the second difference typical value and the preset threshold coefficient to obtain the second difference threshold value; and calculate the product of the third difference typical value and the preset threshold coefficient to obtain the third difference threshold value.

[0186] In some embodiments, as shown in FIG19 , a method for abnormality warning is provided, with a protection device as the execution subject. This embodiment illustrates this method by applying it to the 2xN-take-M redundant structure 700 of the energy storage valve control system shown in FIG13 . The implementation solution provided by this method is similar to the implementation solution described in the abnormality warning method with the first overcurrent detection device 210 as the execution subject in FIG8 . Therefore, the specific limitations in the embodiments provided below can be referred to the limitations of the aforementioned method and will not be repeated here.

[0187] The method is performed by either of the two protection devices. When performed by the first protection device 770 , the method includes:

[0188] In step S310 , a first current value to an Nth current value are received from the first overcurrent detection device 710 to the Nth overcurrent detection device 730 , respectively.

[0189] Specifically, the first protection device 770 includes N buffers, each of which stores the real-time current values ​​and sampling sequence numbers of the N overcurrent detection devices. Therefore, at the same time interval, the first protection device 770 receives the first current value of the first overcurrent detection device 710, the second current value of the second overcurrent detection device 720, and the Nth current value of the Nth overcurrent detection device 730, and stores the first through Nth current values ​​in corresponding buffers. In some examples, the first through Nth current values ​​are instantaneous current values.

[0190] In step S320 , a first current difference to an N−1th current difference are calculated, where the first current difference to the N−1th current difference represent current differences between the first current value and the second current value to the Nth current value.

[0191] In step S330, when the first current difference to the N-1th current difference are respectively greater than the first difference threshold to the N-1th difference threshold corresponding to the first current difference to the N-1th current difference, a first warning signal is output, and the first warning signal indicates that the first overcurrent detection device 710 is abnormal.

[0192] The above-mentioned abnormal warning method uses the first protection device 770 as the main device, receives the current values ​​of N overcurrent detection devices respectively, and obtains the current difference between the first current value and the other N-1 current values ​​based on the first current value, and then compares the first current difference to the N-1th current difference with the corresponding difference threshold value. When these N-1 current differences all exceed the corresponding difference threshold value, an abnormal warning is issued to the first overcurrent detection device 710 corresponding to the first current value. Similarly, horizontal warning is achieved by comparing the sampling data between each overcurrent detection device.

[0193] In some embodiments, the method also includes: respectively calculating the current differences between the Kth current value from the second current value to the Nth current value and the remaining current values ​​from the second current value to the Nth current value; and when the K-1th current difference from the first current difference to the N-1th current difference is greater than the K-1th difference threshold value, the remaining N-2 current differences are less than or equal to the corresponding difference threshold value, and the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value are greater than the corresponding difference threshold value, outputting a second warning signal, the second warning signal indicating that the Kth overcurrent detection device is abnormal.

[0194] In some embodiments, the method further includes: storing a plurality of first to Nth current values ​​in association with a sampling sequence number within a predetermined time period including a plurality of time sections; and when each current value among the stored plurality of first to Nth current values ​​is within a preset current range, calculating a first difference threshold value to an N-1th difference threshold value based on the stored plurality of first to Nth current values, and calculating each difference threshold value of the Kth current value relative to the remaining current values ​​among the second to Nth current values.

[0195] In some embodiments, calculating the first difference threshold value to the N-1th difference threshold value, and calculating the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value, includes: at each time section within a predetermined time period, calculating the first current difference to the N-1th current difference between the stored first current value and the stored second current value to the Nth current value according to the corresponding sampling sequence number, and calculating the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value; and calculating the first difference threshold value to the N-1th difference threshold value based on the first current difference to the N-1th current difference at each time section; and calculating the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value based on the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at each time section.

[0196] In some embodiments, based on the first current difference value to the N-1th current difference value at each time section, the first difference threshold value to the N-1th difference threshold value are calculated; and based on the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at each time section, the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value are calculated, including: calculating the average value of each of the multiple first current differences to the N-1th current differences at multiple time sections to obtain the first difference typical value to the N-1th difference typical value; calculating the first difference typical value to the N-1th difference typical value respectively. The product of the typical value of the N-1th difference value and the preset threshold coefficient is used to obtain the first difference threshold value to the N-1th difference threshold value; the average values ​​of the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value under multiple time sections are calculated one by one to obtain the typical values ​​of the differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value; and the product of the typical values ​​of the differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value and the preset threshold coefficient is calculated to obtain the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value.

[0197] In other embodiments, as shown in FIG20 , an abnormality warning method is provided. The implementation solution for solving the problem provided by the method is similar to the implementation solution recorded in the abnormality warning method with the first overcurrent detection device 510 as the execution body in FIG10 above. Therefore, the specific limitations in the embodiments provided below can refer to the limitations of the above method and will not be repeated here.

[0198] This embodiment uses the method as an example of a two-out-of-three redundant structure 900 in an energy storage valve control system shown in FIG16 , wherein the method is executed by any one of the two-out-of-three protection devices. When executed by the first two-out-of-three protection device 970 , the method includes:

[0199] In step S410 , a first current value, a second current value, and a third current value are received from the first overcurrent detection device 910 , the second overcurrent detection device 920 , and the third overcurrent detection device 930 , respectively.

[0200] Specifically, the first two-out-of-three protection device 970 includes three buffers, each of which stores the real-time current values ​​and sampling sequence numbers of the three overcurrent detection devices. Therefore, at the same time interval, the first two-out-of-three protection device 970 receives the first current value of the first overcurrent detection device 910, the second current value of the second overcurrent detection device 920, and the third current value of the third overcurrent detection device 930, and stores the first current value, the second current value, and the third current value in the corresponding buffers. In some examples, the first current value, the second current value, and the third current value are all instantaneous current values.

[0201] Step S420 , calculating a first current difference between the first current value and the second current value; and calculating a second current difference between the first current value and the third current value.

[0202] Specifically, the first current difference is the absolute value of the instantaneous current difference between the first overcurrent detection device 910 and the second overcurrent detection device 920 , and the second current difference is the absolute value of the instantaneous current difference between the first overcurrent detection device 910 and the third overcurrent detection device 930 .

[0203] Step S430: When the first current difference is greater than the first difference threshold and the second current difference is greater than the second difference threshold, a first warning signal is output, and the first warning signal indicates that the first overcurrent detection device 910 is abnormal.

[0204] Specifically, the first difference threshold is a current difference threshold between the first overcurrent detection device 910 and the second overcurrent detection device 920, and the second difference threshold is a current difference threshold between the first overcurrent detection device 910 and the third overcurrent detection device 930. The first current difference between the first overcurrent detection device 910 and the second overcurrent detection device 920 is compared with the corresponding first difference threshold, and the second current difference between the first overcurrent detection device 910 and the third overcurrent detection device 930 is compared with the corresponding second difference threshold. Based on the comparison results, an abnormal overcurrent detection device can be detected.

[0205] When the first current difference is greater than the first difference threshold value and the second current difference is greater than the second difference threshold value, it is determined that the first overcurrent detection device 910 is abnormal, outputs a first warning signal, and sends it to the monitoring background to achieve real-time warning.

[0206] The above-mentioned abnormal warning method uses the first three-out-of-two protection device 970 as the main device, receives the current values ​​of the three overcurrent detection devices respectively, and takes the first current value as the basis to obtain the first current difference and the second current difference between the first current value and the other two sampling values, and compares the first current difference and the second current difference with the corresponding difference threshold values ​​respectively. When both current differences exceed the corresponding difference threshold values, an abnormal warning is issued to the first overcurrent detection device corresponding to the first current value. Similarly, a horizontal warning is achieved by comparing the sampling data between the overcurrent detection devices, thereby enhancing the ability of multi-directional monitoring of the bridge arm current, enhancing the ability of panoramic fault monitoring and warning of the energy storage valve control system, reducing the dead zone of the warning, and thus protecting the reliable operation of the valve control system from all directions and angles.

[0207] In some embodiments, the method also includes: calculating a third current difference between the second current value and the third current value; when the first current difference is greater than the first difference threshold value, the second current difference is less than or equal to the second difference threshold value, and the third current difference is greater than the third difference threshold value, outputting a second warning signal, and the second warning signal indicates that the second overcurrent detection device 920 is abnormal; and when the first current difference is less than or equal to the first difference threshold value, the second current difference is greater than the second difference threshold value, and the third current difference is greater than the third difference threshold value, outputting a third warning signal, and the third warning signal indicates that the third overcurrent detection device 930 is abnormal.

[0208] In some embodiments, the method further includes: storing multiple first current values, multiple second current values, and multiple third current values ​​in association with a sampling sequence number within a predetermined time period including multiple time sections; when each of the stored multiple first current values, multiple second current values, and multiple third current values ​​is within a preset current range, calculating a first difference threshold value, a second difference threshold value, and a third difference threshold value based on the stored multiple first current values, multiple second current values, and multiple third current values.

[0209] In some embodiments, calculating the first difference threshold value, the second difference threshold value, and the third difference threshold value includes: at each time section within a predetermined time period, calculating the first current difference between the stored first current value and the second current value, the second current difference between the first current value and the third current value, and the third current difference between the second current value and the third current value according to the corresponding sampling sequence number; and processing the first current difference, the second current difference, and the third current difference at each time section to obtain the first difference threshold value, the second difference threshold value, and the third difference threshold value.

[0210] In some embodiments, the first current difference, the second current difference, and the third current difference at each time section are processed separately to obtain the first difference threshold, the second difference threshold, and the third difference threshold, including:

[0211] Calculating an average value of a plurality of first current differences at a plurality of time sections to obtain a typical value of the first difference;

[0212] Calculating the product of the first difference typical value and the preset threshold coefficient to obtain a first difference threshold value;

[0213] Calculating an average value of a plurality of second current differences at a plurality of time sections to obtain a typical value of the second difference;

[0214] Calculating the product of the second difference typical value and the preset threshold coefficient to obtain a second difference threshold value;

[0215] Calculating an average value of a plurality of third current difference values ​​at a plurality of time sections to obtain a typical value of the third difference value; and

[0216] The product of the third difference typical value and the preset threshold coefficient is calculated to obtain the third difference threshold value.

[0217] The above-mentioned abnormal warning methods are all applicable to valve control systems in the engineering integration application of AC / DC microgrid / distribution network technology and battery energy storage technology. In addition to being applicable to abnormal warning of multiple overcurrent detection devices in the valve control system, they can also be applied to abnormal warning between multiple devices of the same level in other power scenarios.

[0218] It should be understood that, although the various steps in the flowcharts involved in the various embodiments described above are displayed in sequence according to the instructions of the arrows, these steps are not necessarily executed in sequence in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the flowcharts involved in the various embodiments described above can include multiple steps or multiple stages, and these steps or stages are not necessarily executed and completed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of steps or stages in other steps.

[0219] In some embodiments, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above-mentioned method embodiments are implemented.

[0220] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiments can be implemented by dedicated circuits, or can be completed by instructing related hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, database or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. For purposes of illustration and not limitation, RAM may be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The processors involved in the various embodiments provided herein may be general-purpose processors, central processing units (CPUs), graphics processors (GPUs), digital signal processors (DSPs), programmable logic devices (PLDs), data processing logic devices based on quantum computing, and the like, without limitation thereto.

[0221] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0222] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. An overcurrent detection device, operating in parallel with N-1 other overcurrent detection devices in an N-of-M redundant configuration of an energy storage valve control system, wherein N is an integer greater than or equal to 3 and M is an integer less than N, wherein the overcurrent detection device is communicatively connected to each of the N-1 other overcurrent detection devices, and wherein the overcurrent detection device comprises: a sampling unit configured to sample the first measuring unit to obtain a first current value; a transceiver unit configured to receive, from the N-1 additional overcurrent detection devices, second current values ​​to Nth current values ​​obtained by each overcurrent detection device sampling the corresponding measurement unit; a difference calculation unit configured to calculate a first current difference to an N-1th current difference, wherein the first current difference to the N-1th current difference represent current differences between the first current value and the second current value to the Nth current value, respectively; as well as An early warning output unit is configured to output a first early warning signal when the first current difference to the N-1th current difference are respectively greater than the first difference threshold to the N-1th difference threshold corresponding to the first current difference to the N-1th current difference, wherein the first early warning signal indicates that the overcurrent detection device is abnormal.

2. The overcurrent detection device according to claim 1, characterized in that: The difference calculation unit is further configured to respectively calculate current differences between a Kth current value from the second current value to the Nth current value and the remaining current values ​​from the second current value to the Nth current value; and The early warning output unit is further configured to: When the K-1th current difference from the first current difference to the N-1th current difference is greater than the K-1th difference threshold value, the remaining N-2 current differences are less than or equal to the corresponding difference threshold values, and the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value are respectively greater than the corresponding difference threshold values, a second warning signal is output, and the second warning signal indicates that the overcurrent detection device that samples the Kth current value is abnormal.

3. The overcurrent detection device according to claim 2, characterized in that: The overcurrent detection device further includes: a storage unit configured to store a plurality of first to Nth current values ​​in association with sampling sequence numbers within a predetermined time period including a plurality of time sections; and A difference threshold value calculation unit is configured to calculate the first difference threshold value to the N-1th difference threshold value based on the stored multiple first to Nth current values ​​when each current value among the stored multiple first to Nth current values ​​is within a preset current range, and calculate each difference threshold value of the Kth current value relative to the remaining current values ​​among the second current value to the Nth current value.

4. The overcurrent detection device according to claim 3, characterized in that: The difference calculation unit is configured to: calculate, at each time section within the predetermined time period, according to the corresponding sampling sequence number, a first current difference to an N-1th current difference between the stored first current value and the stored second current value to the Nth current value, and calculate each current difference between a Kth current value among the stored second current value to the Nth current value and the remaining current values ​​among the second current value to the Nth current value; as well as The difference threshold value calculation unit is configured to: calculate the first difference threshold value to the N-1th difference threshold value based on the first current difference value to the N-1th current difference value in each time section; And based on the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at each time section, the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value are calculated.

5. The overcurrent detection device according to claim 4, characterized in that: The difference calculation unit is configured to: calculate an average value of each of the multiple first current difference values ​​to the multiple N-1th current difference values ​​at the multiple time sections to obtain a first difference typical value to an N-1th difference typical value; calculate each average value of the current difference between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at the multiple time sections in a one-to-one correspondence to each other, to obtain each difference typical value of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value; and The difference threshold value calculation unit is configured to: calculate the product of the first difference typical value to the N-1th difference typical value and a preset threshold coefficient respectively to obtain the first difference threshold value to the N-1th difference threshold value; And respectively calculate the product of each typical value of the difference of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value and the preset threshold coefficient to obtain each difference threshold value of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value.

6. An abnormality warning method, the method being applied to an N-out-of-M redundant structure in an energy storage valve control system, wherein N is an integer greater than or equal to 3, and M is an integer less than N. The N-out-of-M redundant structure comprises first to N-th overcurrent detection devices operating in parallel, and a protection device, wherein the first to N-th overcurrent detection devices are adapted to sample first to N-th measurement units to obtain first to N-th current values, and the protection device is adapted to perform N-out-of-M voting on the overcurrent detection results output by the first to N-th overcurrent detection devices and output the N-out-M voting result, wherein: Any one of the first to the Nth overcurrent detection devices is communicatively connected to N-1 other overcurrent detection devices, and the method is performed by any one of the first to the Nth overcurrent detection devices. When the method is performed by the first overcurrent detection device, the method includes: receiving a second current value to an Nth current value from the second overcurrent detection device to the Nth overcurrent detection device, respectively; calculating a first current difference to an N-1th current difference, where the first current difference to the N-1th current difference represent current differences between the first current value and the second current value to the Nth current value, respectively; and When the first current difference to the N-1th current difference are respectively greater than the first difference threshold to the N-1th difference threshold corresponding to the first current difference to the N-1th current difference, a first warning signal is output, and the first warning signal indicates that the first overcurrent detection device is abnormal.

7. The method according to claim 6, characterized in that Also includes: respectively calculating current differences between a Kth current value from the second current value to the Nth current value and the remaining current values ​​from the second current value to the Nth current value; as well as When the K-1th current difference from the first current difference to the N-1th current difference is greater than the K-1th difference threshold value, the remaining N-2 current differences are less than or equal to the corresponding difference threshold values, and the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value are respectively greater than the corresponding difference threshold values, a second warning signal is output, and the second warning signal indicates that the Kth overcurrent detection device is abnormal.

8. The method according to claim 7, characterized in that Also includes: storing a plurality of first to Nth current values ​​in association with sampling sequence numbers within a predetermined time period including a plurality of time sections; as well as When each current value among the stored multiple first to Nth current values ​​is within a preset current range, the first difference threshold value to the N-1th difference threshold value are calculated based on the stored multiple first to Nth current values, and the difference threshold values ​​of the Kth current value relative to the remaining current values ​​among the second to Nth current values ​​are calculated.

9. The method according to claim 8, characterized in that The calculating of the first difference threshold to the N-1th difference threshold, and the calculating of the difference thresholds of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value, include: At each time section within the predetermined time period, calculating, according to the corresponding sampling sequence number, first current differences to an N-1th current difference between the stored first current value and the stored second current value to an Nth current value, and calculating current differences between a Kth current value among the stored second current value to an Nth current value and the remaining current values ​​among the second current value to the Nth current value; and Based on the first current difference value to the N-1th current difference value at each time section, the first difference threshold value to the N-1th difference threshold value are calculated respectively; and based on the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at each time section, the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value are calculated respectively.

10. The method according to claim 9, characterized in that The first difference threshold value to the N-1th difference threshold value are calculated based on the first current difference value to the N-1th current difference value in each time section respectively; and calculating, based on the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at each time section, respective difference thresholds of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value, including: Calculating an average value of each of the plurality of first current difference values ​​to the plurality of N-1th current difference values ​​at the plurality of time sections to obtain a first difference typical value to an N-1th difference typical value; Calculating the products of the first difference typical value to the N-1th difference typical value and a preset threshold coefficient respectively to obtain the first difference threshold value to the N-1th difference threshold value; Calculating average values ​​of current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at the multiple time sections, respectively, to obtain typical values ​​of the differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value; and The products of typical values ​​of the differences of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value and the preset threshold coefficient are calculated respectively to obtain threshold values ​​of the differences of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value.

11. A protection device, located in an N-out-of-M redundant structure of an energy storage valve control system, wherein N is an integer greater than or equal to 3, and M is an integer less than N. The protection device is adapted to perform N-out-of-M voting on overcurrent detection results output by a first overcurrent detection device to an Nth overcurrent detection device operating in parallel and output the N-out-of-M voting result, the protection device comprising: a receiving unit configured to receive a first current value to an Nth current value from the first overcurrent detection device to the Nth overcurrent detection device, respectively; a difference calculation unit configured to calculate a first current difference to an N-1th current difference, wherein the first current difference to the N-1th current difference represent current differences between the first current value and the second current value to the Nth current value, respectively; as well as An early warning output unit is configured to output a first early warning signal when the first current difference to the N-1th current difference are respectively greater than the first difference threshold to the N-1th difference threshold corresponding to the first current difference to the N-1th current difference, wherein the first early warning signal indicates that the first overcurrent detection device is abnormal.

12. The protection device according to claim 11, characterized in that The difference calculation unit is configured to respectively calculate current differences between a Kth current value from the second current value to the Nth current value and the remaining current values ​​from the second current value to the Nth current value; and The warning output unit is configured as follows: When the K-1th current difference from the first current difference to the N-1th current difference is greater than the K-1th difference threshold value, the remaining N-2 current differences are less than or equal to the corresponding difference threshold values, and each current difference between the Kth current value and the remaining current values ​​from the second current value to the Nth current value is greater than the corresponding difference threshold value, a second warning signal is output, and the second warning signal indicates that the Kth overcurrent detection device is abnormal.

13. The protection device according to claim 12, characterized in that The protection device further comprises: a storage unit configured to store a plurality of first to Nth current values ​​in association with sampling sequence numbers within a predetermined time period including a plurality of time sections; and A difference threshold value calculation unit is configured to calculate the first difference threshold value to the N-1th difference threshold value based on the stored multiple first to Nth current values ​​when each current value among the stored multiple first to Nth current values ​​is within a preset current range, and calculate each difference threshold value of the Kth current value relative to the remaining current values ​​among the second current value to the Nth current value.

14. The protection device according to claim 13, characterized in that The difference calculation unit is configured to: calculate, at each time section within the predetermined time period, according to the corresponding sampling sequence number, a first current difference to an N-1th current difference between the stored first current value and the stored second current value to the Nth current value, and calculate each current difference between a Kth current value among the stored second current value to the Nth current value and the remaining current values ​​among the second current value to the Nth current value; as well as The difference threshold value calculation unit is configured to: calculate the first difference threshold value to the N-1th difference threshold value based on the first current difference value to the N-1th current difference value in each time section; And based on the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at each time section, the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value are calculated.

15. The protection device according to claim 14, characterized in that The difference calculation unit is configured to: calculate an average value of each of the multiple first current difference values ​​to the multiple N-1th current difference values ​​at the multiple time sections to obtain a first difference typical value to an N-1th difference typical value; calculate each average value of the current difference between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at the multiple time sections in a one-to-one correspondence to each other, to obtain each difference typical value of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value; and The difference threshold value calculation unit is configured to: calculate the product of the first difference typical value to the N-1th difference typical value and a preset threshold coefficient respectively to obtain the first difference threshold value to the N-1th difference threshold value; And respectively calculate the product of each typical value of the difference of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value and the preset threshold coefficient to obtain each difference threshold value of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value.

16. An abnormality warning method, the method being applied to an N-out-of-M redundant structure in an energy storage valve control system, wherein N is an integer greater than or equal to 3, and M is an integer less than N. The N-out-of-M redundant structure comprises first to N-th overcurrent detection devices operating in parallel, and a protection device, wherein the first to N-th overcurrent detection devices are adapted to sample first to N-th measurement units to obtain first to N-th current values, and the protection device is adapted to perform N-out-of-M voting on the overcurrent detection results output by the first to N-th overcurrent detection devices and output the N-out-M voting result, wherein: The method is performed by the protection device, and the method includes: receiving a first current value to an Nth current value from the first overcurrent detection device to the Nth overcurrent detection device, respectively; calculating a first current difference to an N-1th current difference, where the first current difference to the N-1th current difference represent current differences between the first current value and the second current value to the Nth current value, respectively; and When the first current difference to the N-1th current difference are respectively greater than the first difference threshold to the N-1th difference threshold corresponding to the first current difference to the N-1th current difference, a first warning signal is output, and the first warning signal indicates that the first overcurrent detection device is abnormal.

17. The method according to claim 16, characterized in that Also includes: respectively calculating current differences between a Kth current value from the second current value to the Nth current value and the remaining current values ​​from the second current value to the Nth current value; as well as When the K-1th current difference from the first current difference to the N-1th current difference is greater than the K-1th difference threshold value, the remaining N-2 current differences are less than or equal to the corresponding difference threshold values, and each current difference between the Kth current value and the remaining current values ​​from the second current value to the Nth current value is greater than the corresponding difference threshold value, a second warning signal is output, and the second warning signal indicates that the Kth overcurrent detection device is abnormal.

18. The method according to claim 17, characterized in that Also includes: storing a plurality of first to Nth current values ​​in association with sampling sequence numbers within a predetermined time period including a plurality of time sections; as well as When each current value among the stored multiple first to Nth current values ​​is within a preset current range, the first difference threshold value to the N-1th difference threshold value are calculated based on the stored multiple first to Nth current values, and the difference threshold values ​​of the Kth current value relative to the remaining current values ​​among the second to Nth current values ​​are calculated.

19. The method according to claim 18, characterized in that The calculating of the first difference threshold to the N-1th difference threshold, and the calculating of the difference thresholds of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value, include: At each time section within the predetermined time period, calculating, according to the corresponding sampling sequence number, first current differences to an N-1th current difference between the stored first current value and the stored second current value to an Nth current value, and calculating current differences between a Kth current value among the stored second current value to an Nth current value and the remaining current values ​​among the second current value to the Nth current value; and Based on the first current difference value to the N-1th current difference value at each time section, the first difference threshold value to the N-1th difference threshold value are calculated respectively; and based on the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at each time section, the difference threshold values ​​of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value are calculated respectively.

20. The method according to claim 19, characterized in that The first difference threshold value to the N-1th difference threshold value are calculated based on the first current difference value to the N-1th current difference value in each time section respectively; and calculating, based on the current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at each time section, respective difference thresholds of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value, including: Calculating an average value of each of the plurality of first current difference values ​​to the plurality of N-1th current difference values ​​at the plurality of time sections to obtain a first difference typical value to an N-1th difference typical value; Calculating the products of the first difference typical value to the N-1th difference typical value and a preset threshold coefficient respectively to obtain the first difference threshold value to the N-1th difference threshold value; Calculating average values ​​of current differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value at the multiple time sections, respectively, to obtain typical values ​​of the differences between the Kth current value and the remaining current values ​​from the second current value to the Nth current value; and The products of typical values ​​of the differences of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value and the preset threshold coefficient are calculated respectively to obtain threshold values ​​of the differences of the Kth current value relative to the remaining current values ​​from the second current value to the Nth current value.

21. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 6 to 10 and 16 to 20 are implemented.

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