Multi-dimensional zero line fault detection method and device

Abstract

The invention discloses a multi-dimensional zero line fault detection method and device, and belongs to the technical field of circuit detection. The method comprises the steps of obtaining a phase voltage unbalance degree, a line phase voltage ratio and a neutral point potential offset value of a target zero line based on a detection period; analyzing the phase voltage unbalance degree, the line phase voltage ratio and the neutral point potential deviation value based on a target logic judgment tool, and obtaining the fault probability of the target zero line in the detection period; and under the condition that the number of the detection periods of which the fault probabilities are greater than or equal to a probability threshold is greater than or equal to a number threshold, determining that the target zero line has a fault. According to the multi-dimensional zero line fault detection method disclosed by the invention, the problem that whether the zero line fails or not is difficult to accurately detect by a single parameter is solved.

Description

Technical Field

[0001] This application belongs to the field of circuit testing technology, and in particular relates to a multi-dimensional neutral wire fault detection method and device. Background Technology

[0002] To prevent equipment failures caused by faults such as a broken neutral wire, inverters typically detect neutral wire faults by detecting the phase voltage.

[0003] However, in special scenarios, such as when the three-phase load on the grid side is extremely balanced, it is difficult to accurately detect whether the neutral wire is faulty by relying solely on the single parameter of phase voltage. Summary of the Invention

[0004] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes a multi-dimensional neutral wire fault detection method and apparatus to solve the problem that a single parameter is insufficient to accurately detect whether a neutral wire is faulty.

[0005] Firstly, this application provides a multi-dimensional neutral wire fault detection method, including: Based on the detection cycle, the phase voltage imbalance of the target neutral line, the line-phase voltage ratio, and the neutral point potential offset are obtained. Based on the target logic judgment tool, the phase voltage imbalance, line-phase voltage ratio and neutral point potential offset are analyzed to obtain the fault probability of the target zero line in the detection cycle. If the number of detection cycles with a fault probability greater than or equal to the probability threshold is greater than or equal to the quantity threshold, the target zero-wire fault is determined.

[0006] According to the multi-dimensional neutral wire fault detection method of this application, the phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset of the target neutral wire are obtained based on the detection cycle. The phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset are analyzed based on the target logic judgment tool to obtain the fault probability of the target neutral wire in the detection cycle. When the number of detection cycles with a fault probability greater than or equal to the probability threshold is greater than or equal to the quantity threshold, the target neutral wire is determined to be faulty. The fault probability of the target neutral wire is comprehensively obtained by using multi-dimensional parameters such as phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset to improve the accuracy of determining whether the target neutral wire is faulty.

[0007] According to one embodiment of this application, the acquisition of phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset of the target neutral line based on the detection cycle includes: The first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage of the target neutral line are obtained based on the detection cycle. The phase voltage imbalance is determined based on the first phase voltage, the second phase voltage, and the third phase voltage. Determine the neutral point potential offset value based on the first line voltage, the second line voltage, and the third line voltage; The line-phase voltage ratio is determined based on the first phase voltage, the second phase voltage, the third phase voltage, the first line voltage, the second line voltage, and the third line voltage.

[0008] According to one embodiment of this application, determining the phase voltage imbalance based on the first phase voltage, the second phase voltage, and the third phase voltage includes: Determine the target maximum value, target minimum value, and first average value of the first phase voltage, second phase voltage, and third phase voltage; The phase voltage imbalance is determined based on the ratio of the difference between the target maximum and the target minimum to the first average value.

[0009] According to one embodiment of this application, determining the neutral point potential offset value based on a first line voltage, a second line voltage, and a third line voltage includes: Based on the first line voltage, the second line voltage, and the third line voltage, determine the first vector voltage, the second vector voltage, and the third vector voltage; The average value of the first vector voltage, the second vector voltage, and the third vector voltage is determined as the neutral point potential offset value.

[0010] According to one embodiment of this application, determining the line-phase voltage ratio based on the first phase voltage, the second phase voltage, the third phase voltage, the first line voltage, the second line voltage, and the third line voltage includes: Determine the first average value of the first phase voltage, the second phase voltage, and the third phase voltage, and determine the second average value of the first line voltage, the second line voltage, and the third line voltage; The line-phase voltage ratio is determined based on the first average value and the second average value.

[0011] According to one embodiment of this application, based on a target logic determination tool, the phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset are analyzed to obtain the fault probability of the target zero line during the detection period, including: Determine the first relationship between phase voltage unbalance and unbalance threshold, the second relationship between line-phase voltage ratio and voltage ratio threshold, and the third relationship between neutral point potential offset and offset threshold. Based on the preset probability allocation rules in the target logic judgment tool, the fault probability of the target zero line in the detection cycle is obtained according to the first relationship, the second relationship and the third relationship.

[0012] Secondly, this application provides a multi-dimensional neutral wire fault detection device, comprising: The first acquisition module is used to acquire the phase voltage imbalance, line-phase voltage ratio and neutral point potential offset of the target neutral line based on the detection cycle. The second acquisition module is used to analyze the phase voltage imbalance, line-phase voltage ratio and neutral point potential offset value based on the target logic judgment tool to obtain the fault probability of the target zero line in the detection cycle. The first determining module is used to determine the target zero-wire fault when the number of detection cycles with a fault probability greater than or equal to the probability threshold is greater than or equal to the quantity threshold.

[0013] According to the multi-dimensional neutral wire fault detection device of this application, the phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset of the target neutral wire are obtained based on the detection cycle. The phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset are analyzed based on the target logic judgment tool to obtain the fault probability of the target neutral wire in the detection cycle. When the number of detection cycles with a fault probability greater than or equal to the probability threshold is greater than or equal to the quantity threshold, the target neutral wire is determined to be faulty. The fault probability of the target neutral wire is obtained comprehensively through multi-dimensional parameters such as phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset to improve the accuracy of determining whether the target neutral wire is faulty.

[0014] According to one embodiment of this application, the first acquisition module includes: The first acquisition unit is used to acquire the first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage of the target neutral line based on the detection cycle. The first determining unit is used to determine the phase voltage imbalance based on the first phase voltage, the second phase voltage, and the third phase voltage; The second determining unit is used to determine the neutral point potential offset value based on the first line voltage, the second line voltage, and the third line voltage. The third determining unit is used to determine the line-phase voltage ratio based on the first phase voltage, the second phase voltage, the third phase voltage, the first line voltage, the second line voltage, and the third line voltage.

[0015] According to one embodiment of this application, the first acquisition unit is used for: Determine the target maximum value, target minimum value, and first average value of the first phase voltage, second phase voltage, and third phase voltage; The phase voltage imbalance is determined based on the ratio of the difference between the target maximum and the target minimum to the first average value.

[0016] According to one embodiment of this application, the first determining module includes: The fourth determining unit is used to determine the first relationship between the phase voltage unbalance degree and the unbalance degree threshold, the second relationship between the line-phase voltage ratio and the voltage ratio threshold, and the third relationship between the neutral point potential offset value and the offset threshold. The second acquisition unit is used to acquire the fault probability of the target zero line in the detection period based on the preset probability allocation rules in the target logic judgment tool and according to the first relationship, the second relationship and the third relationship.

[0017] Thirdly, this application provides an electronic device, including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the multi-dimensional neutral wire fault detection method described in the first aspect.

[0018] Fourthly, this application provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the multi-dimensional zero-wire fault detection method described in the first aspect.

[0019] Fifthly, this application provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the multi-dimensional zero-line fault detection method described in the first aspect.

[0020] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0021] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is one of the flowcharts of the multi-dimensional zero-wire fault detection method provided in the embodiments of this application; Figure 2 This is the second flowchart of the multi-dimensional zero-wire fault detection method provided in the embodiments of this application; Figure 3 This is a schematic diagram of the structure of the multi-dimensional zero-wire fault detection device provided in the embodiments of this application; Figure 4 This is a schematic diagram of the structure of the electronic device provided in the embodiments of this application. Detailed Implementation

[0022] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0023] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0024] The multi-dimensional neutral wire fault detection method and apparatus provided in this application will be described in detail below with reference to the accompanying drawings, through specific embodiments and application scenarios.

[0025] Among them, the multi-dimensional zero-line fault detection method can be applied to the terminal, and can be executed by the hardware or software in the terminal.

[0026] The multi-dimensional neutral wire fault detection method provided in this application embodiment can be implemented by a functional module or functional entity in an electrical or electronic device such as an inverter or an integrated energy storage unit. The following description uses an electronic device as the implementing entity to illustrate the multi-dimensional neutral wire fault detection method provided in this application embodiment.

[0027] like Figure 1 As shown, the multi-dimensional zero-line fault detection method includes steps 110, 120 and 130.

[0028] Step 110: Based on the detection cycle, obtain the phase voltage imbalance of the target zero line, the line-phase voltage ratio, and the neutral point potential offset.

[0029] In actual implementation, the detection period can be a preset period for acquiring the phase voltage imbalance of the target neutral line, the line-phase voltage ratio, and the neutral point potential offset. The detection period can be any theoretically feasible duration; for example, the detection period can be 5 milliseconds.

[0030] In some embodiments, phase voltage data and line voltage data can be acquired, and the phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset of the target neutral line can be obtained based on the phase voltage data and line voltage data.

[0031] Step 120: Analyze the phase voltage imbalance, line-phase voltage ratio and neutral point potential offset value based on the target logic judgment tool to obtain the fault probability of the target zero line in the detection cycle.

[0032] In actual execution, the target logic determination tool has several pre-set probability allocation rules.

[0033] In some embodiments, the target logic determination tool can analyze the phase voltage imbalance, line-phase voltage ratio and neutral point potential offset based on several probability allocation rules to obtain the fault probability of the target zero line during the detection period.

[0034] Step 130: If the number of detection cycles with a fault probability greater than or equal to the probability threshold is greater than or equal to the quantity threshold, determine the target zero-wire fault.

[0035] In actual implementation, the probability threshold can be a pre-set value, and it can be any theoretically feasible percentage. For example, the probability threshold could be 80%.

[0036] In actual implementation, the quantity threshold can be determined based on a preset maximum acceptable failure time. The quantity threshold can be the quotient of the preset maximum acceptable failure time and the detection cycle. For example, if the maximum acceptable failure time is 30 milliseconds, the detection cycle is 5 milliseconds, and the quantity threshold is 6.

[0037] In some embodiments, the phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset can be continuously acquired for several detection cycles. Based on a target logic determination tool, the phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset for each detection cycle are analyzed to obtain the fault probability for that detection cycle. The fault probability of each detection cycle is compared with a probability threshold. If the number of detection cycles with a fault probability greater than or equal to the probability threshold is greater than or equal to a quantity threshold, a target neutral wire fault is determined.

[0038] According to the multi-dimensional neutral wire fault detection method of this application embodiment, the phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset value of the target neutral wire are obtained based on the detection cycle; the phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset value are analyzed based on the target logic judgment tool to obtain the fault probability of the target neutral wire in the detection cycle; if the number of detection cycles with a fault probability greater than or equal to the probability threshold is greater than or equal to the number threshold, the target neutral wire fault is determined. The fault probability of the target neutral wire is comprehensively obtained through multi-dimensional parameters such as phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset value to improve the accuracy of determining whether the target neutral wire is faulty.

[0039] In some embodiments, the first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage of the target neutral line are acquired based on the detection cycle; the phase voltage imbalance is determined based on the first phase voltage, second phase voltage, and third phase voltage; the neutral point potential offset is determined based on the first line voltage, second line voltage, and third line voltage; and the line-phase voltage ratio is determined based on the first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage.

[0040] In some embodiments, the first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage of the target neutral line can be obtained based on an analog-to-digital converter (ADC).

[0041] In some embodiments, after obtaining the first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage of the target neutral line, the effective values ​​of the first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage can be calculated, for example, by using the peak detection method, the distillation averaging method, or any theoretically feasible effective value calculation method.

[0042] According to the multi-dimensional neutral wire fault detection method of this application embodiment, the first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage of the target neutral wire are obtained based on the detection cycle; the phase voltage imbalance is determined based on the first phase voltage, second phase voltage, and third phase voltage; the neutral point potential offset is determined based on the first line voltage, second line voltage, and third line voltage; the line-phase voltage ratio is determined based on the first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage; the phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset are analyzed based on the target logic judgment tool to obtain the fault probability of the target neutral wire in the detection cycle; if the number of detection cycles with a fault probability greater than or equal to the probability threshold is greater than or equal to the number threshold, the target neutral wire is determined to be faulty. By comprehensively obtaining the fault probability of the target neutral wire through multi-dimensional parameters such as phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset, the accuracy of determining whether the target neutral wire is faulty is improved.

[0043] In some embodiments, a target maximum value, a target minimum value, and a first average value of the first phase voltage, the second phase voltage, and the third phase voltage are determined; and the phase voltage imbalance is determined based on the ratio of the difference between the target maximum value and the target minimum value to the first average value.

[0044] In some embodiments, the target maximum value is the largest among the first phase voltage, the second phase voltage, and the third phase voltage, the target minimum value is the smallest among the first phase voltage, the second phase voltage, and the third phase voltage, and the first average value is the average of the first phase voltage, the second phase voltage, and the third phase voltage.

[0045] In some embodiments, the phase voltage imbalance can be determined based on the following formula: ; in, Indicates the phase voltage imbalance. Indicates the target maximum value. This represents the minimum target value. This represents the first average value.

[0046] According to the multi-dimensional neutral wire fault detection method of this application embodiment, the first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage of the target neutral wire are obtained based on the detection cycle; the phase voltage imbalance is determined based on the first phase voltage, second phase voltage, and third phase voltage; the neutral point potential offset is determined based on the first line voltage, second line voltage, and third line voltage; the line-phase voltage ratio is determined based on the first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage; the phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset are analyzed based on the target logic judgment tool to obtain the fault probability of the target neutral wire in the detection cycle; if the number of detection cycles with a fault probability greater than or equal to the probability threshold is greater than or equal to the number threshold, the target neutral wire is determined to be faulty. By comprehensively obtaining the fault probability of the target neutral wire through multi-dimensional parameters such as phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset, the accuracy of determining whether the target neutral wire is faulty is improved.

[0047] In some embodiments, a first vector voltage, a second vector voltage, and a third vector voltage are determined based on a first line voltage, a second line voltage, and a third line voltage; the average of the first vector voltage, the second vector voltage, and the third vector voltage is determined as the neutral point potential offset value.

[0048] In some embodiments, the first vector voltage, the second vector voltage, the third vector voltage, and the neutral point potential offset can be obtained based on the following formulas: ; ; ; ; in, Represents the first vector voltage. Indicates the second vector voltage. Indicates the third vector voltage. Indicates the first line voltage. Indicates the second line voltage. This represents the neutral point potential offset.

[0049] According to the multi-dimensional neutral wire fault detection method of this application embodiment, the first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage of the target neutral wire are obtained based on the detection cycle; the phase voltage imbalance is determined based on the first phase voltage, second phase voltage, and third phase voltage; the neutral point potential offset is determined based on the first line voltage, second line voltage, and third line voltage; the line-phase voltage ratio is determined based on the first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage; the phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset are analyzed based on the target logic judgment tool to obtain the fault probability of the target neutral wire in the detection cycle; if the number of detection cycles with a fault probability greater than or equal to the probability threshold is greater than or equal to the number threshold, the target neutral wire is determined to be faulty. By comprehensively obtaining the fault probability of the target neutral wire through multi-dimensional parameters such as phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset, the accuracy of determining whether the target neutral wire is faulty is improved.

[0050] In some embodiments, a first average value of the first phase voltage, the second phase voltage, and the third phase voltage is determined, and a second average value of the first line voltage, the second line voltage, and the third line voltage is determined; based on the first average value and the second average value, the line-phase voltage ratio is determined.

[0051] In actual implementation, the second average value is the average of the first line voltage, the second line voltage, and the third line voltage.

[0052] In a normal three-phase four-wire system, the ratio of any line voltage to its corresponding phase voltage is equal to... This ratio is stable and unchanging, regardless of whether the load is balanced.

[0053] In some embodiments, the line-phase voltage ratio can be determined based on the following formula: ; Among them, K UL This represents the ratio of line-phase voltages. This represents the first average value. This represents the second average value.

[0054] According to the multi-dimensional neutral wire fault detection method of this application embodiment, the first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage of the target neutral wire are obtained based on the detection cycle; the phase voltage imbalance is determined based on the first phase voltage, second phase voltage, and third phase voltage; the neutral point potential offset is determined based on the first line voltage, second line voltage, and third line voltage; the line-phase voltage ratio is determined based on the first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage; the phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset are analyzed based on the target logic judgment tool to obtain the fault probability of the target neutral wire in the detection cycle; if the number of detection cycles with a fault probability greater than or equal to the probability threshold is greater than or equal to the number threshold, the target neutral wire is determined to be faulty. By comprehensively obtaining the fault probability of the target neutral wire through multi-dimensional parameters such as phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset, the accuracy of determining whether the target neutral wire is faulty is improved.

[0055] In some embodiments, a first relationship between phase voltage imbalance and imbalance threshold is determined, a second relationship between line-phase voltage ratio and voltage ratio threshold is determined, and a third relationship between neutral point potential offset and offset threshold is determined; based on the preset probability allocation rules in the target logic determination tool, the fault probability of the target zero line in the detection cycle is obtained according to the first relationship, the second relationship and the third relationship.

[0056] In practice, the imbalance threshold can be based on a pre-set value for the current power system. For example, the imbalance threshold could be... Any value in the range.

[0057] In practice, the voltage ratio threshold can be based on a preset value of the current power system. The voltage ratio threshold can include a first voltage ratio threshold and a second voltage ratio threshold. For example, the first voltage ratio threshold can be any value between 1.05 and 1.1, and the second voltage ratio threshold can be any value between 0.9 and 0.95.

[0058] In practice, the offset threshold can be based on a pre-set value for the current power system. For example, the offset threshold can be any value between 15 volts and 30 volts.

[0059] In actual implementation, the first relationship represents the relationship between the phase voltage unbalance degree and the unbalance degree threshold; the second relationship represents the relationship between the phase voltage ratio and the voltage ratio threshold; and the third relationship represents the relationship between the neutral point potential offset value and the offset threshold.

[0060] In some embodiments, the target logic determination tool may include the following preset probability allocation rules: exist and In this case, the probability of failure is 0.9; exist and In this case, the probability of failure is 0.8; exist and In this case, the probability of failure is 0.85; exist and and In this case, the probability of failure is 0.98; exist and and In this case, the probability of failure is 0.7; exist and and In this case, the probability of failure is 0.65; exist and In this case, the probability of failure is 0.6; exist and and In this case, the probability of failure is 0; in, Indicates the phase voltage imbalance. K represents the neutral point potential offset. UL This represents the ratio of line-phase voltages. Indicates the unbalance threshold. Indicates the second voltage ratio threshold. Indicates the first voltage ratio threshold. This indicates the offset threshold.

[0061] According to the multi-dimensional neutral wire fault detection method of this application embodiment, the first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage of the target neutral wire are obtained based on the detection cycle; the phase voltage imbalance is determined based on the first phase voltage, second phase voltage, and third phase voltage; the neutral point potential offset is determined based on the first line voltage, second line voltage, and third line voltage; the line-phase voltage ratio is determined based on the first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage; the phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset are analyzed based on the target logic judgment tool to obtain the fault probability of the target neutral wire in the detection cycle; if the number of detection cycles with a fault probability greater than or equal to the probability threshold is greater than or equal to the number threshold, the target neutral wire is determined to be faulty. By comprehensively obtaining the fault probability of the target neutral wire through multi-dimensional parameters such as phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset, the accuracy of determining whether the target neutral wire is faulty is improved.

[0062] To better understand the multi-dimensional zero-wire fault detection method provided in the embodiments of this application, further explanation is provided below. It should be understood that the following discussion is merely exemplary.

[0063] This application provides a multi-dimensional neutral wire fault detection method, the specific steps of which are as follows: Figure 2 As shown: Step 210: Obtain the first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage of the target neutral line based on the detection cycle.

[0064] In some embodiments, the first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage of the target neutral line can be obtained based on an analog-to-digital converter (ADC).

[0065] In some embodiments, after obtaining the first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage of the target neutral line, the effective values ​​of the first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage can be calculated, for example, by using the peak detection method, the distillation averaging method, or any theoretically feasible effective value calculation method.

[0066] In actual implementation, the detection period can be a preset period for acquiring the phase voltage imbalance of the target neutral line, the line-phase voltage ratio, and the neutral point potential offset. The detection period can be any theoretically feasible duration; for example, the detection period can be 5 milliseconds.

[0067] Step 220: Determine the target maximum value, target minimum value, and first average value of the first phase voltage, second phase voltage, and third phase voltage; determine the phase voltage imbalance based on the ratio of the difference between the target maximum value and the target minimum value to the first average value.

[0068] In some embodiments, the target maximum value is the largest among the first phase voltage, the second phase voltage, and the third phase voltage, the target minimum value is the smallest among the first phase voltage, the second phase voltage, and the third phase voltage, and the first average value is the average of the first phase voltage, the second phase voltage, and the third phase voltage.

[0069] In some embodiments, the phase voltage imbalance can be determined based on the following formula: ; in, Indicates the phase voltage imbalance. Indicates the target maximum value. This represents the minimum target value. This represents the first average value.

[0070] Step 230: Based on the first line voltage, the second line voltage, and the third line voltage, determine the first vector voltage, the second vector voltage, and the third vector voltage; determine the average value of the first vector voltage, the second vector voltage, and the third vector voltage as the neutral point potential offset value.

[0071] In some embodiments, the first vector voltage, the second vector voltage, the third vector voltage, and the neutral point potential offset can be obtained based on the following formulas: ; ; ; ; in, Represents the first vector voltage. Indicates the second vector voltage. Indicates the third vector voltage. Indicates the first line voltage. Indicates the second line voltage. This represents the neutral point potential offset.

[0072] Step 240: Determine the first average value of the first phase voltage, the second phase voltage, and the third phase voltage, and determine the second average value of the first line voltage, the second line voltage, and the third line voltage; based on the first average value and the second average value, determine the line-phase voltage ratio.

[0073] In actual implementation, the second average value is the average of the first line voltage, the second line voltage, and the third line voltage.

[0074] In a normal three-phase four-wire system, the ratio of any line voltage to its corresponding phase voltage is equal to... This ratio is stable and unchanging, regardless of whether the load is balanced.

[0075] In some embodiments, the line-phase voltage ratio can be determined based on the following formula: ; Among them, K UL This represents the ratio of line-phase voltages. This represents the first average value. This represents the second average value.

[0076] Step 250: Determine the first relationship between phase voltage imbalance and imbalance threshold, determine the second relationship between line-phase voltage ratio and voltage ratio threshold, and determine the third relationship between neutral point potential offset and offset threshold; based on the preset probability allocation rules in the target logic judgment tool, obtain the fault probability of the target neutral line in the detection cycle according to the first, second and third relationships.

[0077] In practice, the imbalance threshold can be based on a pre-set value for the current power system. For example, the imbalance threshold could be... Any value in the range.

[0078] In practice, the voltage ratio threshold can be based on a preset value of the current power system. The voltage ratio threshold can include a first voltage ratio threshold and a second voltage ratio threshold. For example, the first voltage ratio threshold can be any value between 1.05 and 1.1, and the second voltage ratio threshold can be any value between 0.9 and 0.95.

[0079] In practice, the offset threshold can be based on a pre-set value for the current power system. For example, the offset threshold can be any value between 15 volts and 30 volts.

[0080] In actual implementation, the first relationship represents the relationship between the phase voltage unbalance degree and the unbalance degree threshold; the second relationship represents the relationship between the phase voltage ratio and the voltage ratio threshold; and the third relationship represents the relationship between the neutral point potential offset value and the offset threshold.

[0081] In some embodiments, the target logic determination tool may include the following preset probability allocation rules: exist and In this case, the probability of failure is 0.9; exist and In this case, the probability of failure is 0.8; exist and In this case, the probability of failure is 0.85; exist and and In this case, the probability of failure is 0.98; exist and and In this case, the probability of failure is 0.7; exist and and In this case, the probability of failure is 0.65; exist and In this case, the probability of failure is 0.6; exist and and In this case, the probability of failure is 0; in, Indicates the phase voltage imbalance. K represents the neutral point potential offset. UL This represents the ratio of line-phase voltages. Indicates the unbalance threshold. Indicates the second voltage ratio threshold. Indicates the first voltage ratio threshold. This indicates the offset threshold.

[0082] Step 260: If the number of detection cycles with a fault probability greater than or equal to the probability threshold is greater than or equal to the quantity threshold, determine the target zero-wire fault.

[0083] In actual implementation, the probability threshold can be a pre-set value, and it can be any theoretically feasible percentage. For example, the probability threshold could be 80%.

[0084] In actual implementation, the quantity threshold can be determined based on a preset maximum acceptable failure time. The quantity threshold can be the quotient of the preset maximum acceptable failure time and the detection cycle. For example, if the maximum acceptable failure time is 30 milliseconds, the detection cycle is 5 milliseconds, and the quantity threshold is 6.

[0085] In some embodiments, the phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset can be continuously acquired for several detection cycles. Based on a target logic determination tool, the phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset for each detection cycle are analyzed to obtain the fault probability for that detection cycle. The fault probability of each detection cycle is compared with a probability threshold. If the number of detection cycles with a fault probability greater than or equal to the probability threshold is greater than or equal to a quantity threshold, a target neutral wire fault is determined.

[0086] This application also provides a multi-dimensional zero-line fault detection device.

[0087] like Figure 3 As shown, the multi-dimensional zero-line fault detection device 300 includes: a first acquisition module 310, a second acquisition module 320, and a first determination module 330.

[0088] The first acquisition module 310 is used to acquire the phase voltage imbalance, line-phase voltage ratio and neutral point potential offset of the target neutral line based on the detection cycle. The second acquisition module 320 is used to analyze the phase voltage imbalance, line-phase voltage ratio and neutral point potential offset value based on the target logic judgment tool to obtain the fault probability of the target zero line in the detection period. The first determining module 330 is used to determine the target zero line fault when the number of detection cycles with a fault probability greater than or equal to the probability threshold is greater than or equal to the quantity threshold.

[0089] According to the multi-dimensional neutral wire fault detection device of this application, the phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset of the target neutral wire are obtained based on the detection cycle. The phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset are analyzed based on the target logic judgment tool to obtain the fault probability of the target neutral wire in the detection cycle. When the number of detection cycles with a fault probability greater than or equal to the probability threshold is greater than or equal to the quantity threshold, the target neutral wire is determined to be faulty. The fault probability of the target neutral wire is obtained comprehensively through multi-dimensional parameters such as phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset to improve the accuracy of determining whether the target neutral wire is faulty.

[0090] In some embodiments, the first acquisition module 310 includes: The first acquisition unit is used to acquire the first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage of the target neutral line based on the detection cycle. The first determining unit is used to determine the phase voltage imbalance based on the first phase voltage, the second phase voltage, and the third phase voltage; The second determining unit is used to determine the neutral point potential offset value based on the first line voltage, the second line voltage, and the third line voltage. The third determining unit is used to determine the line-phase voltage ratio based on the first phase voltage, the second phase voltage, the third phase voltage, the first line voltage, the second line voltage, and the third line voltage.

[0091] In some embodiments, the first acquisition unit is used for: Determine the target maximum value, target minimum value, and first average value of the first phase voltage, second phase voltage, and third phase voltage; The phase voltage imbalance is determined based on the ratio of the difference between the target maximum and the target minimum to the first average value.

[0092] In some embodiments, the first acquisition unit is used for: Based on the first line voltage, the second line voltage, and the third line voltage, determine the first vector voltage, the second vector voltage, and the third vector voltage; The average value of the first vector voltage, the second vector voltage, and the third vector voltage is determined as the neutral point potential offset value.

[0093] In some embodiments, the first acquisition unit is used for: Determine the first average value of the first phase voltage, the second phase voltage, and the third phase voltage, and determine the second average value of the first line voltage, the second line voltage, and the third line voltage; The line-phase voltage ratio is determined based on the first average value and the second average value.

[0094] In some embodiments, the first determining module 330 includes: The fourth determining unit is used to determine the first relationship between the phase voltage unbalance degree and the unbalance degree threshold, the second relationship between the line-phase voltage ratio and the voltage ratio threshold, and the third relationship between the neutral point potential offset value and the offset threshold. The second acquisition unit is used to acquire the fault probability of the target zero line in the detection period based on the preset probability allocation rules in the target logic judgment tool and according to the first relationship, the second relationship and the third relationship.

[0095] The multi-dimensional neutral wire fault detection device in this application embodiment can be deployed on an inverter or an integrated energy storage unit; however, this application embodiment does not impose any specific limitations.

[0096] The multi-dimensional neutral wire fault detection device in this application embodiment can be a device with an operating system. This operating system can be a Microsoft (Windows) operating system, an Android operating system, an iOS operating system, or other possible operating systems; this application embodiment does not specifically limit it.

[0097] The multi-dimensional neutral wire fault detection device 300 provided in this application embodiment can achieve... Figures 1 to 2 The various processes implemented in the method implementation examples will not be described again here to avoid repetition.

[0098] In some embodiments, such as Figure 4 As shown, this application embodiment also provides an electronic device 400, including a processor 401, a memory 402, and a computer program stored in the memory 402 and executable on the processor 401. When the program is executed by the processor 401, it implements the various processes of the above-described multi-dimensional zero-line fault detection method embodiment and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0099] This application also provides a non-transitory computer-readable storage medium storing a computer program. When the computer program is executed by a processor, it implements the various processes of the above-described multi-dimensional zero-line fault detection method embodiments and achieves the same technical effect. To avoid repetition, it will not be described again here.

[0100] The processor is the processor in the electronic device described in the above embodiments. The readable storage medium includes computer-readable storage media, such as computer read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk.

[0101] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the above-described multi-dimensional zero-line fault detection method.

[0102] The processor is the processor in the electronic device described in the above embodiments. The readable storage medium includes computer-readable storage media, such as computer read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk.

[0103] This application embodiment also provides a chip, which includes a processor and a communication interface. The communication interface is coupled to the processor. The processor is used to run programs or instructions to implement the various processes of the above-described multi-dimensional zero-wire fault detection method embodiment and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0104] It should be understood that the chip mentioned in the embodiments of this application may also be referred to as a system-on-a-chip, system chip, chip system, or system-on-a-chip, etc.

[0105] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0106] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a computer software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0107] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

[0108] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0109] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A multi-dimensional zero-wire fault detection method, characterized in that, include: Based on the detection cycle, the phase voltage imbalance of the target neutral line, the line-phase voltage ratio, and the neutral point potential offset are obtained. Based on the target logic judgment tool, the phase voltage imbalance, the line-phase voltage ratio, and the neutral point potential offset are analyzed to obtain the fault probability of the target neutral line during the detection period. If the number of detection cycles in which the fault probability is greater than or equal to the probability threshold is greater than or equal to the quantity threshold, the target zero-line fault is determined.

2. The multi-dimensional zero-line fault detection method according to claim 1, characterized in that, The acquisition of phase voltage imbalance, line-phase voltage ratio, and neutral point potential offset of the target neutral line based on the detection cycle includes: The first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage of the target neutral line are obtained based on the detection cycle. The phase voltage imbalance is determined based on the first phase voltage, the second phase voltage, and the third phase voltage; The neutral point potential offset value is determined based on the first line voltage, the second line voltage, and the third line voltage. The line-phase voltage ratio is determined based on the first phase voltage, the second phase voltage, the third phase voltage, the first line voltage, the second line voltage, and the third line voltage.

3. The multi-dimensional zero-line fault detection method according to claim 2, characterized in that, The determination of phase voltage imbalance based on the first phase voltage, the second phase voltage, and the third phase voltage includes: Determine the target maximum value, target minimum value, and first average value of the first phase voltage, the second phase voltage, and the third phase voltage; The phase voltage imbalance is determined based on the ratio of the difference between the target maximum value and the target minimum value to the first average value.

4. The multi-dimensional zero-line fault detection method according to claim 2, characterized in that, The step of determining the neutral point potential offset value based on the first line voltage, the second line voltage, and the third line voltage includes: Based on the first line voltage, the second line voltage, and the third line voltage, a first vector voltage, a second vector voltage, and a third vector voltage are determined. The average of the first vector voltage, the second vector voltage, and the third vector voltage is determined as the neutral point potential offset value.

5. The multi-dimensional zero-line fault detection method according to claim 2, characterized in that, The step of determining the line-phase voltage ratio based on the first phase voltage, the second phase voltage, the third phase voltage, the first line voltage, the second line voltage, and the third line voltage includes: Determine a first average value of the first phase voltage, the second phase voltage, and the third phase voltage, and determine a second average value of the first line voltage, the second line voltage, and the third line voltage; The line-phase voltage ratio is determined based on the first average value and the second average value.

6. The multi-dimensional zero-line fault detection method according to claim 1, characterized in that, The target logic-based judgment tool analyzes the phase voltage imbalance, the line-phase voltage ratio, and the neutral point potential offset to obtain the fault probability of the target neutral line during the detection period, including: A first relationship is determined between the phase voltage imbalance degree and the imbalance degree threshold; a second relationship is determined between the line-phase voltage ratio and the voltage ratio threshold; and a third relationship is determined between the neutral point potential offset value and the offset threshold. Based on the preset probability allocation rules in the target logic determination tool, the fault probability of the target zero line in the detection period is obtained according to the first relationship, the second relationship and the third relationship.

7. A multi-dimensional neutral wire fault detection device, characterized in that, include: The first acquisition module is used to acquire the phase voltage imbalance, line-phase voltage ratio and neutral point potential offset of the target neutral line based on the detection cycle. The second acquisition module is used to analyze the phase voltage imbalance, the line-phase voltage ratio, and the neutral point potential offset value based on the target logic judgment tool to obtain the fault probability of the target neutral line during the detection period. The first determining module is used to determine the target zero-wire fault when the number of detection cycles in which the fault probability is greater than or equal to the probability threshold is greater than or equal to the quantity threshold.

8. The multi-dimensional neutral wire fault detection device according to claim 7, characterized in that, The first acquisition module includes: The first acquisition unit is used to acquire the first phase voltage, second phase voltage, third phase voltage, first line voltage, second line voltage, and third line voltage of the target neutral line based on the detection cycle. The first determining unit is used to determine the phase voltage imbalance based on the first phase voltage, the second phase voltage, and the third phase voltage; The second determining unit is used to determine the neutral point potential offset value based on the first line voltage, the second line voltage, and the third line voltage. The third determining unit is used to determine the line-phase voltage ratio based on the first phase voltage, the second phase voltage, the third phase voltage, the first line voltage, the second line voltage, and the third line voltage.

9. The multi-dimensional neutral wire fault detection device according to claim 8, characterized in that, The first acquisition unit is used for: Determine the target maximum value, target minimum value, and first average value of the first phase voltage, the second phase voltage, and the third phase voltage; The phase voltage imbalance is determined based on the ratio of the difference between the target maximum value and the target minimum value to the first average value.

10. The multi-dimensional zero-line fault detection device according to claim 7, characterized in that, The first determination module includes: The fourth determining unit is used to determine a first relationship between the phase voltage unbalance degree and the unbalance degree threshold, a second relationship between the line-phase voltage ratio and the voltage ratio threshold, and a third relationship between the neutral point potential offset value and the offset threshold. The second acquisition unit is used to acquire the fault probability of the target zero line in the detection period based on the preset probability allocation rules in the target logic judgment tool, according to the first relationship, the second relationship and the third relationship.

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