Method for determining grounding fault of power distribution network, electronic equipment and program product

Abstract

The embodiment of the invention provides a method for determining a grounding fault of a power distribution network, electronic equipment and a program product. The method comprises the following steps: obtaining first zero-sequence current and second zero-sequence current of each distribution line in the power distribution network in response to the fact that zero-sequence voltage of a bus in the power distribution network meets a first fault detection requirement; wherein the first zero-sequence current is obtained based on the first current transformer, and the second zero-sequence current is obtained based on the second current transformer; the transformation ratio of the first current transformer is greater than that of the second current transformer; if it is determined that the first zero-sequence current is larger than or equal to the zero-sequence current threshold value, it is determined that the corresponding distribution line has a ground fault; and if it is determined that the first zero-sequence current is smaller than the zero-sequence current threshold value, analyzing at least one of the zero-sequence voltage and the second zero-sequence current based on a second fault detection requirement to determine a ground fault detection result of the corresponding distribution line. The method is used for achieving the effect of determining the grounding fault of the power distribution network accurately.

Description

Technical Field

[0001] The present application relates to the technical field of distribution networks, and in particular, to a method for determining a grounding fault in a distribution network, an electronic device, and a program product. Background Art

[0002] During the operation of a distribution network, grounding fault detection is a key technology to ensure the safe operation of the power system.

[0003] In the prior art, if the zero-sequence voltage of a bus is greater than the starting limit value, the zero-sequence current in each distribution line can be detected by a current transformer, and whether a corresponding distribution line has a grounding fault is determined according to the magnitude relationship between the zero-sequence current and a preset threshold value.

[0004] However, if the zero-sequence current in the distribution line fluctuates greatly, it will cause the current transformer to be unable to meet the requirements of both high precision and anti-saturation ability at the same time, thereby affecting the accuracy of the detected zero-sequence current and further affecting the accuracy of determining the grounding fault in the distribution network. Summary of the Invention

[0005] Embodiments of the present application provide a method for determining a grounding fault in a distribution network, an electronic device, and a program product, so as to achieve the effect of improving the accuracy of determining the grounding fault in the distribution network.

[0006] In a first aspect, an embodiment of the present application provides a method for determining a grounding fault in a distribution network, including:

[0007] In response to the zero-sequence voltage of a bus in the distribution network satisfying a first fault detection requirement, obtaining a first zero-sequence current and a second zero-sequence current of each distribution line in the distribution network;

[0008] Wherein, the first fault detection requirement is used to determine whether the distribution network needs to perform grounding fault detection; wherein, the first zero-sequence current is obtained based on a first current transformer, and the second zero-sequence current is obtained based on a second current transformer; the turns ratio of the first current transformer is greater than the turns ratio of the second current transformer;

[0009] If it is determined that the first zero-sequence current is greater than or equal to a zero-sequence current threshold value, it is determined that the corresponding distribution line has a grounding fault; wherein, the zero-sequence current threshold value is used for comparison processing with the first zero-sequence current to determine the grounding fault detection result of the corresponding distribution line; the zero-sequence current threshold value is indicated by a second fault detection requirement; the second fault detection requirement is used to determine whether the distribution line has a grounding fault;

[0010] If it is determined that the first zero-sequence current is less than the zero-sequence current threshold, at least one of the zero-sequence voltage and the second zero-sequence current is analyzed based on the second fault detection requirement to determine the grounding fault detection result of the corresponding distribution line.

[0011] In a possible implementation, the second fault detection requirement further indicates a first zero-sequence voltage threshold; wherein, the first zero-sequence voltage threshold is used to compare with the zero-sequence voltage when the first zero-sequence current is less than the zero-sequence current threshold to determine the grounding fault detection result of the corresponding distribution line; analyzing at least one of the zero-sequence voltage and the second zero-sequence current based on the second fault detection requirement to determine the grounding fault detection result of the corresponding distribution line includes: if it is determined that the zero-sequence voltage is greater than or equal to the first zero-sequence voltage threshold, it is determined that there is no grounding fault in the corresponding distribution line; if it is determined that the zero-sequence voltage is less than the first zero-sequence voltage threshold, the zero-sequence voltage and the second zero-sequence current are subjected to a phase comparison process based on the second fault detection requirement to determine the grounding fault detection result of the corresponding distribution line.

[0012] In a possible implementation, the second fault detection requirement further indicates a phase threshold range; wherein, the phase threshold range is used to perform a phase comparison process when the first zero-sequence current is less than the zero-sequence current threshold and the zero-sequence voltage is less than the first zero-sequence voltage threshold to determine the grounding fault detection result of the corresponding distribution line; performing a phase comparison process on the zero-sequence voltage and the second zero-sequence current based on the second fault detection requirement to determine the grounding fault detection result of the corresponding distribution line includes: taking the phase of the zero-sequence voltage as the reference phase and obtaining the phase of the second zero-sequence current; if it is determined that the phase of the second zero-sequence current is within the phase threshold range, it is determined that there is a grounding fault in the corresponding distribution line; otherwise, it is determined that there is no grounding fault in the corresponding distribution line.

[0013] In a possible implementation, the first fault detection requirement indicates a second zero-sequence voltage threshold; wherein, the second zero-sequence voltage threshold is used to compare with the zero-sequence voltage to determine whether the distribution network needs to perform a grounding fault detection; wherein, if the zero-sequence voltage is greater than or equal to the second zero-sequence voltage threshold, it is determined that the distribution network needs to perform a grounding fault detection.

[0014] In a possible implementation manner, the second fault detection requirement further indicates a first zero-sequence voltage threshold; wherein, the first zero-sequence voltage threshold is used to compare and process with the zero-sequence voltage when the first zero-sequence current is less than the zero-sequence current threshold, so as to determine the grounding fault detection result of the corresponding distribution line; wherein, the first zero-sequence voltage threshold is less than the second zero-sequence voltage threshold.

[0015] In a possible implementation manner, the first current transformer and the second current transformer satisfy at least one of the following: the transformation ratio of the first current transformer is greater than a first transformation ratio threshold, and the transformation ratio of the second current transformer is less than a second transformation ratio threshold; wherein, the first transformation ratio threshold is greater than the second transformation ratio threshold; the ratio between the transformation ratio of the first current transformer and the transformation ratio of the second current transformer is greater than a preset ratio threshold; the first current transformer is a phase current transformer; the second current transformer is a zero-sequence current transformer.

[0016] In a second aspect, an embodiment of the present application provides a device for determining a grounding fault of a distribution network, including:

[0017] An acquisition module, configured to acquire a first zero-sequence current and a second zero-sequence current of each distribution line in the distribution network in response to the zero-sequence voltage of the bus in the distribution network satisfying a first fault detection requirement; wherein, the first fault detection requirement is used to determine whether the distribution network needs to perform a grounding fault detection; wherein, the first zero-sequence current is obtained based on a first current transformer, and the second zero-sequence current is obtained based on a second current transformer; the transformation ratio of the first current transformer is greater than the transformation ratio of the second current transformer;

[0018] A determination module, configured to determine that there is a grounding fault in the corresponding distribution line if it is determined that the first zero-sequence current is greater than or equal to a zero-sequence current threshold; wherein, the zero-sequence current threshold is used to compare and process with the first zero-sequence current to determine the grounding fault detection result of the corresponding distribution line; the zero-sequence current threshold is indicated by a second fault detection requirement; the second fault detection requirement is used to determine whether there is a grounding fault in the distribution line; if it is determined that the first zero-sequence current is less than the zero-sequence current threshold, at least one of the zero-sequence voltage and the second zero-sequence current is analyzed based on the second fault detection requirement to determine the grounding fault detection result of the corresponding distribution line.

[0019] In a possible implementation manner, the second fault detection requirement further indicates a first zero-sequence voltage threshold; wherein, the first zero-sequence voltage threshold is used to compare with the zero-sequence voltage when the first zero-sequence current is less than the zero-sequence current threshold, so as to determine the grounding fault detection result of the corresponding distribution line; the determining module is specifically configured to, if it is determined that the zero-sequence voltage is greater than or equal to the first zero-sequence voltage threshold, determine that there is no grounding fault in the corresponding distribution line; if it is determined that the zero-sequence voltage is less than the first zero-sequence voltage threshold, perform a phase comparison process on the zero-sequence voltage and the second zero-sequence current based on the second fault detection requirement, so as to determine the grounding fault detection result of the corresponding distribution line.

[0020] In a possible implementation manner, the second fault detection requirement further indicates a phase threshold range; wherein, the phase threshold range is used to perform a phase comparison process when the first zero-sequence current is less than the zero-sequence current threshold and the zero-sequence voltage is less than the first zero-sequence voltage threshold, so as to determine the grounding fault detection result of the corresponding distribution line; the determining module is further specifically configured to use the phase of the zero-sequence voltage as the reference phase, and obtain the phase of the second zero-sequence current; if it is determined that the phase of the second zero-sequence current is within the phase threshold range, determine that there is a grounding fault in the corresponding distribution line; otherwise, determine that there is no grounding fault in the corresponding distribution line.

[0021] In a possible implementation manner, the first fault detection requirement indicates a second zero-sequence voltage threshold; wherein, the second zero-sequence voltage threshold is used to compare with the zero-sequence voltage to determine whether the distribution network needs to perform a grounding fault detection; wherein, if the zero-sequence voltage is greater than or equal to the second zero-sequence voltage threshold, it is determined that the distribution network needs to perform a grounding fault detection.

[0022] In a possible implementation manner, the second fault detection requirement further indicates a first zero-sequence voltage threshold; wherein, the first zero-sequence voltage threshold is used to compare with the zero-sequence voltage when the first zero-sequence current is less than the zero-sequence current threshold, so as to determine the grounding fault detection result of the corresponding distribution line; wherein, the first zero-sequence voltage threshold is less than the second zero-sequence voltage threshold.

[0023] In a possible implementation, the first current transformer and the second current transformer satisfy at least one of the following: the transformation ratio of the first current transformer is greater than a first transformation ratio threshold, and the transformation ratio of the second current transformer is less than a second transformation ratio threshold; wherein, the first transformation ratio threshold is greater than the second transformation ratio threshold; the ratio between the transformation ratio of the first current transformer and the transformation ratio of the second current transformer is greater than a preset ratio threshold; the first current transformer is a phase current transformer; the second current transformer is a zero-sequence current transformer.

[0024] In a third aspect, an embodiment of the present application provides an electronic device, including: a memory, a processor;

[0025] The memory stores computer-executable instructions;

[0026] The processor executes the computer-executable instructions stored in the memory, so that the processor executes the above first aspect and / or various possible implementation manners of the first aspect.

[0027] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, in which computer-executable instructions are stored, and when the computer-executable instructions are executed by a processor, they are used to implement the above first aspect and / or various possible implementation manners of the first aspect.

[0028] In a fifth aspect, an embodiment of the present application provides a computer program product, including a computer program, and when the computer program is executed by a processor, it implements the above first aspect and / or various possible implementation manners of the first aspect.

[0029] The method, electronic device and program product for determining a grounding fault of a distribution network provided by the embodiments of the present application, by responding to the zero-sequence voltage of a busbar in the distribution network satisfying a first fault detection requirement, obtaining the first zero-sequence current and the second zero-sequence current of each distribution line in the distribution network, if it is determined that the first zero-sequence current is greater than or equal to the zero-sequence current threshold, it is determined that the corresponding distribution line has a grounding fault, if it is determined that the first zero-sequence current is less than the zero-sequence current threshold, at least one of the zero-sequence voltage and the second zero-sequence current is analyzed based on a second fault detection requirement to determine the grounding fault detection result of the corresponding distribution line, wherein, two zero-sequence currents of a distribution line are obtained through two current transformers with different transformation ratios, and the grounding faults of each distribution network are determined in combination with the corresponding fault detection requirements, which solves the problem that one current transformer cannot simultaneously meet the requirements of high precision and anti-saturation ability, and further improves the accuracy of determining the grounding fault of the distribution network on the basis of improving the accuracy of the detected zero-sequence current. Description of the Drawings

[0030] The accompanying drawings here are incorporated into the description and form a part of this description, showing embodiments consistent with this application, and are used together with the description to explain the principles of this application.

[0031] Figure 1 Schematic flow of the method for determining the grounding fault of the distribution network provided for this application Figure 1 ;

[0032] Figure 2 Schematic flow of the method for determining the grounding fault of the distribution network provided for this application Figure 2 ;

[0033] Figure 3 Schematic flow of the method for determining the grounding fault of the distribution network provided for this application Figure 3 ;

[0034] Figure 4 Schematic structural diagram of the device for determining the grounding fault of the distribution network provided for this application;

[0035] Figure 5 Schematic structural diagram of the electronic device provided for this application.

[0036] Through the above accompanying drawings, specific embodiments of this application have been shown, and there will be more detailed descriptions hereinafter. These drawings and textual descriptions are not intended to limit the scope of the concept of this application in any way, but to illustrate the concept of this application to those skilled in the art by referring to specific embodiments. Detailed implementation manners

[0037] Here, the exemplary embodiments will be described in detail, and the examples are shown in the accompanying drawings. When the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementation manners described in the following exemplary embodiments do not represent all implementation manners consistent with this application. On the contrary, they are merely examples of devices and methods consistent with some aspects of this application as detailed in the appended claims.

[0038] In the prior art, if the zero-sequence voltage of the bus is greater than the starting limit value, the zero-sequence current in each distribution line can be detected through a current transformer, and whether the corresponding distribution line has a grounding fault can be determined according to the magnitude relationship between the zero-sequence current and a preset threshold. However, if the zero-sequence current in the distribution line fluctuates greatly, it will cause the current transformer to be unable to meet the requirements of both high precision and anti-saturation ability at the same time, thereby affecting the accuracy of the detected zero-sequence current and further affecting the accuracy of determining the grounding fault of the distribution network.

[0039] The method for determining the grounding fault of a distribution network provided by this application obtains the first zero-sequence current and the second zero-sequence current of each distribution line in the distribution network by responding to the zero-sequence voltage of the bus in the distribution network satisfying the first fault detection requirement. If it is determined that the first zero-sequence current is greater than or equal to the zero-sequence current threshold, it is determined that the corresponding distribution line has a grounding fault. If it is determined that the first zero-sequence current is less than the zero-sequence current threshold, at least one of the zero-sequence voltage and the second zero-sequence current is analyzed based on the second fault detection requirement to determine the grounding fault detection result of the corresponding distribution line. Among them, the two zero-sequence currents of a distribution line are obtained through two current transformers with different turns ratios, and the grounding faults of each distribution network are determined in combination with the corresponding fault detection requirements, solving the problem that a single current transformer cannot simultaneously meet the requirements of high precision and anti-saturation ability. On the basis of improving the accuracy of the detected zero-sequence current, the accuracy of determining the grounding fault of the distribution network is further improved.

[0040] The following uses specific embodiments to detail the technical solution of this application and how the technical solution of this application solves the above technical problems. These several specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of this application will be described below with reference to the accompanying drawings.

[0041] Figure 1 Flow schematic of the method for determining the grounding fault of a distribution network provided by this application Figure 1 , such as Figure 1 shown, this method includes:

[0042] Step S101, in response to the zero-sequence voltage of the bus in the distribution network satisfying the first fault detection requirement, obtain the first zero-sequence current and the second zero-sequence current of each distribution line in the distribution network.

[0043] Among them, a distribution network refers to a power grid that receives electric energy from a transmission network or a regional power plant and distributes it locally through distribution facilities or by voltage levels to various users. The distribution network consists of overhead lines, cables, poles, distribution transformers, disconnect switches, reactive power compensators, and some auxiliary facilities, etc. Its main function is to distribute electric energy in the power grid. It usually adopts a closed-loop design and open-loop operation method to improve the flexibility of operation and power supply reliability. The voltage levels of the distribution network are diverse, including high-voltage distribution networks (6~110kV), low-voltage distribution networks (0.4kV), etc., to meet the needs of different users.

[0044] Among them, the busbar is a special conductor in the power grid, usually a group of conductors located inside the substation, used to connect various devices. The main function of the busbar is to collect, distribute, and transmit electric energy. In the power system, the busbar connects each current-carrying branch circuit in the distribution device to ensure the efficient transmission of electric energy between different devices. The busbar is usually composed of flat conductors made of copper or aluminum, with a relatively large diameter and width to carry a large amount of current. The structural design and material selection of the busbar are carefully calculated to ensure that it can meet the requirements of the continuous working current and have sufficient short-circuit thermal stability performance.

[0045] Among them, the distribution line is one of the main components in the power system that transmits electric energy from the power source to the user terminals. It is connected through various cables and wires, and distributes the electric energy output by the high-voltage transmission transformer to each power consumption point according to a certain capacity and voltage level. According to different voltage levels, the distribution lines can be divided into high-voltage distribution lines (110 kV and above), medium-voltage distribution lines (10 kV - 35 kV), and low-voltage distribution lines (220 V - 1000 V). These lines respectively undertake the important task of transmitting electric energy from power plants or substations to various users in cities, rural areas, and industrial areas.

[0046] Specifically, inside the substation, the busbar forms a complex electric energy transmission network by connecting electrical devices such as transformers and switchgear. This network is connected to the external power grid through distribution lines, forming a complete power system. The distribution lines then transmit electric energy from the substation or power plant to the location where the users are through forms such as cables or overhead conductors. In this process, the distribution lines need to consider various factors such as terrain, traffic, and environment to ensure the reliable transmission of electric energy.

[0047] Among them, the zero-sequence voltage refers to the co-directional voltage component generated when, in a three-phase power system, during an asymmetric fault (such as single-phase grounding or two-phase grounding), the vector sum of the three-phase voltages is no longer zero. It is mainly used to detect and locate grounding faults.

[0048] Among them, grounding fault detection refers to detecting whether there are grounding faults in each distribution line of the distribution network. To avoid wasting computing resources and improve the efficiency of determining grounding faults in the distribution network, it can first be determined whether grounding fault detection is required in the distribution network, that is, whether the distribution network includes distribution lines with grounding faults. If it includes, further grounding fault detection is carried out, that is, detecting which distribution line in each distribution line has a grounding fault. Otherwise, continue to monitor whether grounding fault detection is required in the distribution network.

[0049] Among them, the first fault detection requirement is used to determine whether grounding fault detection is required in the distribution network.

[0050] Among them, the first fault detection requirement can also be referred to as the starting requirement for ground fault detection. Specifically, this application does not limit the first fault detection requirement. Any preset requirement for determining whether a distribution network needs to perform ground fault detection based on zero-sequence voltage can be used as the first fault detection requirement provided by this application. Optionally, the first fault detection requirement provided by this application may include at least one analysis method such as threshold analysis, trend analysis, deviation value analysis, and comparison analysis. Among them, if the zero-sequence voltage meets the requirements corresponding to any one of the analysis methods in the first fault detection requirement, it is determined that the zero-sequence voltage meets the first fault detection requirement.

[0051] Specifically, if the zero-sequence voltage meets the first fault detection requirement, it is determined that the distribution network needs to perform ground fault detection, that is, the distribution network includes a power distribution line with a ground fault. If the zero-sequence voltage does not meet the first fault detection requirement, it is determined that the distribution network does not need to perform ground fault detection, that is, the distribution network includes a power distribution line without a ground fault. At this time, the zero-sequence voltage can be continuously monitored so that ground fault detection can be performed in a timely manner when it is detected that the zero-sequence voltage meets the first fault detection requirement, improving the accuracy and efficiency of determining the ground fault in the distribution network.

[0052] Specifically, in response to the zero-sequence voltage of the bus in the distribution network meeting the first fault detection requirement, it is determined that the distribution network needs to perform ground fault detection. Therefore, the first zero-sequence current and the second zero-sequence current of each power distribution line in the distribution network can be obtained to perform ground fault detection on each power distribution line.

[0053] Among them, the zero-sequence current refers to the current component generated due to unbalanced three-phase currents or faults (such as single-phase ground faults) in a three-phase alternating current system. It usually shows that the vector sum of the three-phase currents is not zero, that is, I0 = I a +I b +I c , where I a , I b , I c are the three-phase currents respectively. Under normal circumstances, the vector sum of the three-phase currents is zero, but when the system shows imbalance or fault, the zero-sequence current will appear.

[0054] Among them, the first zero-sequence current is obtained based on the first current transformer, and the second zero-sequence current is obtained based on the second current transformer. The transformation ratio of the first current transformer is greater than that of the second current transformer.

[0055] Among them, a current transformer (CT for short) is an instrument that measures by converting a large current on the primary side into a small current on the secondary side based on the principle of electromagnetic induction, facilitating measurement, protection, and control. For example, in a high-voltage power system, the primary-side current can be as high as several thousand amperes or even tens of thousands of amperes. Directly measuring such a large current is very difficult and dangerous. Through a current transformer, the large current can be transformed into a standard small current of 5A or 1A, enabling measuring instruments and protection devices to work safely and accurately.

[0056] Among them, among the numerous parameters of the current transformer, the transformation ratio of the current transformer is a very important parameter. The transformation ratio of the current transformer refers to the ratio of the primary-side current to the secondary-side current. For example, a current transformer with a transformation ratio of 1000:5 means that when the primary-side current is 1000A, the secondary-side current is 5A.

[0057] Specifically, this application does not limit the process of obtaining the first zero-sequence current and the second zero-sequence current of each distribution line in the distribution network. Optionally, it can be obtained based on the first current transformer and the second current transformer configured in the distribution line.

[0058] Among them, based on the above description of the current transformer, when the current on the distribution line side of the current transformer, that is, the primary side, is large, if the current transformer uses a small transformation ratio, it is very easy to become saturated, resulting in a deviation between the current value detected on the protection side, that is, the secondary side, and the actual value, thereby affecting the accuracy of grounding fault detection. When the current on the distribution line side of the current transformer, that is, the primary side, is small, such as in the case of a high-resistance grounding fault, if the current transformer uses a large transformation ratio, it will cause the current value detected on the protection side, that is, the primary side, to be extremely small, exceeding the range that can be accurately detected under the accuracy limit of the current transformer itself, thereby affecting the accuracy of grounding fault detection.

[0059] Therefore, based on two current transformers with different transformation ratios, this application can obtain two zero-sequence currents corresponding to the distribution line to improve the accuracy of determining the grounding fault of the distribution line based on the zero-sequence current.

[0060] Step S102: If it is determined that the first zero-sequence current is greater than or equal to the zero-sequence current threshold, it is determined that the corresponding distribution line has a grounding fault.

[0061] Specifically, based on the above description of the first zero-sequence current, the first zero-sequence current is the zero-sequence current determined based on the current transformer with a larger transformation ratio among the two current transformers. Among them, since the current transformer with a larger transformation ratio needs to consider the impact of detection accuracy on accuracy, when it is determined that the first zero-sequence current is larger, it can be considered that the detection accuracy of the current transformer has no impact on the accuracy of the first zero-sequence current.

[0062] Among them, the zero-sequence current threshold is used for comparison processing with the first zero-sequence current to determine the grounding fault detection result of the corresponding distribution line.

[0063] Specifically, based on the above descriptions of the zero-sequence current and the first zero-sequence current, on the premise that the numerical value of the zero-sequence current is accurately detected, if the zero-sequence current is greater than a certain threshold, it is determined that there is a grounding fault in the corresponding distribution line. Therefore, the zero-sequence current threshold refers to the threshold that can be used to determine that the first zero-sequence current is accurately detected and to determine whether there is a grounding fault in the corresponding distribution line.

[0064] Among them, the present application does not limit the determination process of the zero-sequence current threshold. Optionally, a pre-calibrated threshold for determining whether the detected first zero-sequence current is accurate can be obtained; a pre-calibrated threshold for comparing with the accurately detected first zero-sequence current to determine whether there is a grounding fault in the corresponding distribution line can be obtained; and then the larger value of the two obtained thresholds is determined as the zero-sequence current threshold. The zero-sequence current threshold obtained through the above process can be used to determine whether the detected first zero-sequence current is accurately detected and to determine whether there is a grounding fault in the corresponding distribution line.

[0065] Among them, the zero-sequence current threshold is indicated by the second fault detection requirement. The second fault detection requirement is used to determine whether there is a grounding fault in the distribution line.

[0066] Specifically, based on the above description of the first fault detection requirement, in response to the zero-sequence voltage of the bus in the distribution network satisfying the first fault detection requirement, it is possible to determine whether there is a grounding fault in each distribution line in the distribution network. At this time, this process can be implemented based on the second fault detection requirement for determining whether there is a grounding fault in the distribution line. Among them, based on the above description of the zero-sequence current threshold, the zero-sequence current threshold is indicated by the second fault detection requirement.

[0067] Step S103: If it is determined that the first zero-sequence current is less than the zero-sequence current threshold, then analyze at least one of the zero-sequence voltage and the second zero-sequence current based on the second fault detection requirement to determine the grounding fault detection result of the corresponding distribution line.

[0068] Specifically, based on the above descriptions of the first zero-sequence current and the zero-sequence current threshold, if it is determined that the first zero-sequence current is less than the zero-sequence current threshold, it is impossible to determine whether the first zero-sequence current is accurately detected, or it is impossible to determine that there is no grounding fault in the corresponding distribution line through the zero-sequence current threshold.

[0069] Among them, if the zero-sequence current threshold is a pre-calibrated threshold for determining whether the detected first zero-sequence current is accurate, and the first zero-sequence current is less than the zero-sequence current threshold, it cannot be directly determined that the first zero-sequence current is less than the pre-calibrated threshold for comparing with the accurately detected first zero-sequence current to determine whether there is a ground fault in the corresponding distribution line. At the same time, the first zero-sequence current being less than the zero-sequence current threshold indicates that the detected first zero-sequence current is inaccurate. Therefore, if the first zero-sequence current is less than the zero-sequence current threshold, due to the inaccurate detection of the corresponding first zero-sequence current, and the zero-sequence current threshold cannot determine the reason for the fault in the corresponding distribution line, other parameters are needed to further judge the corresponding distribution line.

[0070] Specifically, based on the description in step S102, the second fault detection requirement is used to determine whether there is a ground fault in the distribution line. Therefore, at least one of the zero-sequence voltage and the second zero-sequence current can be further analyzed based on the second fault detection requirement to determine the ground fault detection result of the corresponding distribution line.

[0071] Specifically, this application does not limit the process of analyzing at least one of the zero-sequence voltage and the second zero-sequence current based on the second fault detection requirement to determine the ground fault detection result of the corresponding distribution line. Optionally, the second fault detection requirement can also include at least one analysis method such as threshold analysis, change trend analysis, deviation value analysis, and comparison analysis. Among them, if at least one of the zero-sequence voltage and the second zero-sequence current meets the requirements corresponding to any analysis method in the second fault detection requirement, the ground fault detection result of the corresponding distribution line can be determined.

[0072] The method for determining the ground fault of the distribution network provided by the embodiment of this application obtains the first zero-sequence current and the second zero-sequence current of each distribution line in the distribution network by responding to the zero-sequence voltage of the bus in the distribution network meeting the first fault detection requirement. If it is determined that the first zero-sequence current is greater than or equal to the zero-sequence current threshold, it is determined that there is a ground fault in the corresponding distribution line. If it is determined that the first zero-sequence current is less than the zero-sequence current threshold, at least one of the zero-sequence voltage and the second zero-sequence current is analyzed based on the second fault detection requirement to determine the ground fault detection result of the corresponding distribution line. Among them, the two zero-sequence currents of a distribution line are obtained through two current transformers with different turns ratios, and the ground faults of each distribution network are determined by combining the corresponding fault detection requirements, which solves the problem that a single current transformer cannot simultaneously meet the requirements of high precision and anti-saturation ability, and further improves the accuracy of determining the ground fault of the distribution network on the basis of improving the accuracy of the detected zero-sequence current.

[0073] Optionally, based on the descriptions of the current transformer and the transformation ratio of the current transformer in the above embodiments, after obtaining the first zero-sequence current and the second zero-sequence current of each distribution line in the distribution network, the first zero-sequence current and the second zero-sequence current can be analyzed and processed to obtain the true zero-sequence current of the corresponding distribution line, and based on the determined true zero-sequence current and a preset current threshold, it can be determined whether there is a ground fault in the corresponding distribution line.

[0074] Among them, the present application does not limit the process of analyzing and processing the first zero-sequence current and the second zero-sequence current to obtain the true zero-sequence current of the corresponding distribution line. Optionally, the first zero-sequence current and the second zero-sequence current can be calculated and processed by means of weighted averaging or the like to obtain the true zero-sequence current of the corresponding distribution line.

[0075] Among them, by analyzing and processing the first zero-sequence current and the second zero-sequence current to obtain the true zero-sequence current of the corresponding distribution line, the accuracy limitation and saturation risk of the current transformer are avoided, and the accuracy of determining the ground fault in the distribution network is further improved.

[0076] Figure 2 Flow schematic of the method for determining the ground fault of the distribution network provided by the present application Figure 2 , as Figure 2 shown, on the basis of the Figure 1 embodiment, this embodiment details the analysis of at least one of the zero-sequence voltage and the second zero-sequence current based on the second fault detection requirement to determine the ground fault detection result of the corresponding distribution line. The method includes:

[0077] Step S201, determine whether the zero-sequence voltage is greater than or equal to the first zero-sequence voltage threshold.

[0078] Specifically, based on the judgment process in step S103, if it is determined that the first zero-sequence current is less than the zero-sequence current threshold, although it is impossible to determine whether the detected first zero-sequence current is accurate, it can be determined that the zero-sequence current corresponding to the distribution line will not be too large. On this premise, if it is determined that the zero-sequence voltage of the bus is large, it is determined that there is no ground fault in the corresponding distribution line. At this time, the zero-sequence voltage of the bus may be affected by other factors such as unbalanced load and system resonance, resulting in an increase in the zero-sequence voltage, but no ground fault actually occurs.

[0079] Among them, the second fault detection requirement also indicates the first zero-sequence voltage threshold. The first zero-sequence voltage threshold is used to compare with the zero-sequence voltage when the first zero-sequence current is less than the zero-sequence current threshold to determine the ground fault detection result of the corresponding distribution line.

[0080] Among them, this application does not limit the first zero-sequence voltage threshold. Optionally, the first zero-sequence voltage threshold can be pre-calibrated when the first zero-sequence current is less than the zero-sequence current threshold, and is a voltage threshold that excludes the influence of other factors causing the zero-sequence voltage to increase.

[0081] Step S202: If it is determined that the zero-sequence voltage is greater than or equal to the first zero-sequence voltage threshold, it is determined that the corresponding distribution line has no grounding fault.

[0082] Specifically, based on the description of the first zero-sequence voltage threshold in step S201, when the first zero-sequence current is less than the zero-sequence current threshold, if it is determined that the zero-sequence voltage is greater than or equal to the first zero-sequence voltage threshold, it is determined that the corresponding distribution line has no grounding fault.

[0083] Step S203: If it is determined that the zero-sequence voltage is less than the first zero-sequence voltage threshold, the phase comparison process is performed on the zero-sequence voltage and the second zero-sequence current based on the second fault detection requirement to determine the grounding fault detection result of the corresponding distribution line.

[0084] Specifically, based on the description of the first zero-sequence voltage threshold in step S201, when the first zero-sequence current is less than the zero-sequence current threshold, if it is determined that the zero-sequence voltage is less than the first zero-sequence voltage threshold, it cannot be determined that the corresponding distribution line has no grounding fault. At this time, if it is necessary to accurately determine whether the corresponding distribution line has a grounding fault, further analysis is required based on the second fault detection requirement.

[0085] Specifically, the zero-sequence voltage and the second zero-sequence current can be subjected to phase comparison processing based on the second fault detection requirement to determine the grounding fault detection result of the corresponding distribution line. The specific reason is that when a grounding fault occurs in the corresponding distribution line, there are significant characteristics between the zero-sequence current and the zero-sequence voltage of the bus. Therefore, the zero-sequence voltage and the zero-sequence current can be subjected to phase comparison processing to determine the grounding fault detection result of the corresponding distribution line. At the same time, based on the above description, at this time, it has been determined that the first zero-sequence current is less than the zero-sequence current threshold. Based on the description of the first zero-sequence current and the first zero-sequence current transformer, due to the accuracy limitation of the zero-sequence current transformer, the first zero-sequence current measured at this time may not be accurate, resulting in inaccurate phase information provided. Therefore, if phase comparison processing is performed based on it and the zero-sequence voltage, the grounding fault detection result of the corresponding distribution line finally determined will be inaccurate. At this time, based on the description of the second zero-sequence current and the second zero-sequence current transformer, when the first zero-sequence current is less than the zero-sequence current threshold, the zero-sequence current in the distribution line is small, and the easy saturation of the second zero-sequence transformer will not affect the accuracy of the zero-sequence current detection. Therefore, the accuracy of the measured second zero-sequence current is higher than that of the measured first zero-sequence current, and the accuracy of the provided phase information is also higher. Therefore, performing phase comparison processing based on the second zero-sequence current and the zero-sequence voltage can improve the accuracy of the grounding fault detection result of the corresponding distribution line.

[0086] Among them, in the process described above, if the detection accuracy of the first zero-sequence current or the second zero-sequence current is high, the provided phase information is consistent.

[0087] The process provided by the embodiment of the present application analyzes at least one of the zero-sequence voltage and the second zero-sequence current based on the second fault detection requirement to determine the grounding fault detection result of the corresponding distribution line. By judging whether the zero-sequence voltage is greater than or equal to the first zero-sequence voltage threshold, if it is determined that the zero-sequence voltage is greater than or equal to the first zero-sequence voltage threshold, it is determined that there is no grounding fault in the corresponding distribution line. If it is determined that the zero-sequence voltage is less than the first zero-sequence voltage threshold, the phase comparison process is performed on the zero-sequence voltage and the second zero-sequence current based on the second fault detection requirement to determine the grounding fault detection result of the corresponding distribution line. Among them, by setting the first zero-sequence voltage threshold, it is possible to efficiently and accurately identify the situation where the zero-sequence voltage is increased due to other interference factors rather than a grounding fault, improving the accuracy and efficiency of determining the grounding fault in the distribution network. Among them, in the process of further determining whether there is a fault in the corresponding distribution line by means of phase comparison, based on the second zero-sequence current with higher accuracy and more accurate phase information in this case, the accuracy of determining the grounding fault in the distribution network can be further improved. Based on the above description, the process provided by the embodiment of the present application analyzes at least one of the zero-sequence voltage and the second zero-sequence current based on the second fault detection requirement to determine the grounding fault detection result of the corresponding distribution line, which can improve the accuracy and efficiency of determining the grounding fault in the distribution network.

[0088] Figure 3 It is a schematic flow chart of the method for determining the grounding fault of the distribution network provided by the present application Figure 3 , such as Figure 3 shown, based on the embodiment of Figure 1 or Figure 2 On the basis of the embodiment, the phase comparison process of the zero-sequence voltage and the second zero-sequence current based on the second fault detection requirement is described in detail to determine the grounding fault detection result of the corresponding distribution line. The method includes:

[0089] Step S301: Taking the phase of the zero-sequence voltage as the reference phase, obtain the phase of the second zero-sequence current.

[0090] Specifically, the present application does not limit the process of taking the phase of the zero-sequence voltage as the reference phase and obtaining the phase of the second zero-sequence current. Optionally, the phase of the zero-sequence voltage can be obtained from a preset phase measuring instrument. Among them, the phase measuring instrument herein is connected to the voltage transformer for detecting the zero-sequence voltage and the second current transformer for detecting the second zero-sequence current, and is set to use the phase of the zero-sequence voltage as the reference phase.

[0091] Step S302: Judge whether the phase of the second zero-sequence current is within the phase threshold range.

[0092] Among them, since the phase of the second zero-sequence current is the phase obtained with the phase of the zero-sequence voltage as the reference phase, the phase of the second zero-sequence current can characterize the angular relationship between the second zero-sequence current and the zero-sequence voltage. Among them, if the second zero-sequence current is less than zero, it is determined that the angle of the second zero-sequence current lags behind the angle of the zero-sequence voltage; if the second zero-sequence current is greater than zero, it is determined that the angle of the second zero-sequence current leads the angle of the zero-sequence voltage.

[0093] Among them, in the process of describing the phase characteristics of the grounding fault of the distribution line, if the angle of the second zero-sequence current lags behind the angle of the zero-sequence voltage and the lagged angle exceeds a certain threshold, a positive-direction grounding fault will occur. At this time, it can be determined that the distribution line corresponding to the second zero-sequence current has a grounding fault.

[0094] Therefore, after obtaining the phase of the second zero-sequence current with the phase of the zero-sequence voltage as the reference phase, it is possible to determine whether the corresponding distribution line has a grounding fault by setting a threshold.

[0095] Among them, the second fault detection requirement also indicates a phase threshold range. The phase threshold range is used to perform phase comparison processing when the first zero-sequence current is less than the zero-sequence current threshold and the zero-sequence voltage is less than the first zero-sequence voltage threshold, so as to determine the grounding fault detection result of the corresponding distribution line.

[0096] Specifically, based on the above description, the phase threshold range indicated by the second fault detection requirement is the threshold range of the phase used to determine whether a positive-direction grounding fault occurs in the distribution network, that is, the threshold range of the phase used to determine whether the distribution line corresponding to the second zero-sequence current has a grounding fault.

[0097] Specifically, the present application does not limit the phase threshold range. Any threshold range of the phase that can be used to determine whether a positive-direction grounding fault occurs in the distribution network, that is, the threshold range of the phase used to determine whether the distribution line corresponding to the second zero-sequence current has a grounding fault, can be used as the phase threshold range provided by the present application. Optionally, the phase threshold range provided by the present application can be from -180° to -90°.

[0098] Step S303: If it is determined that the phase of the second zero-sequence current is within the phase threshold range, it is determined that the corresponding distribution line has a grounding fault.

[0099] Specifically, based on the above description of the phase of the second zero-sequence current and the phase threshold range, if it is determined that the phase of the second zero-sequence current is within the phase threshold range, it is determined that the corresponding distribution line has a grounding fault.

[0100] Step S304: If it is determined that the phase of the second zero-sequence current is outside the phase threshold range, it is determined that the corresponding distribution line does not have a grounding fault.

[0101] Specifically, based on the above description of the phase of the second zero-sequence current and the phase threshold range, if it is determined that the phase of the second zero-sequence current is outside the phase threshold range, it is determined that there is a ground fault in the corresponding distribution line.

[0102] In the embodiment of the present application, the process of comparing the phases of the zero-sequence voltage and the second zero-sequence current based on the second fault detection requirement to determine the ground fault detection result of the corresponding distribution line is as follows: taking the phase of the zero-sequence voltage as the reference phase, obtaining the phase of the second zero-sequence current, and determining whether the phase of the second zero-sequence current is within the phase threshold range. If it is determined that the phase of the second zero-sequence current is within the phase threshold range, it is determined that there is a ground fault in the corresponding distribution line. If it is determined that the phase of the second zero-sequence current is outside the phase threshold range, it is determined that there is no ground fault in the corresponding distribution line. Among them, by performing the phase comparison process through the phase threshold range indicated by the second fault detection requirement, the accuracy of the corresponding distribution line can be determined efficiently and accurately, and further improve the accuracy of determining the ground fault in the distribution network.

[0103] In a possible embodiment, the first fault detection requirement indicates a second zero-sequence voltage threshold. The second zero-sequence voltage threshold is used to compare with the zero-sequence voltage to determine whether the distribution network needs to perform ground fault detection. If the zero-sequence voltage is greater than or equal to the second zero-sequence voltage threshold, it is determined that the distribution network needs to perform ground fault detection.

[0104] Specifically, based on the description of the zero-sequence voltage in step S101, the zero-sequence voltage to a certain extent characterizes the distribution lines in the distribution network including those with ground faults. However, due to the influence of external interference factors, when a small zero-sequence voltage appears, it cannot directly determine the distribution lines in the distribution network including those with ground faults. Therefore, by setting a voltage threshold, the influence of external interference factors can be excluded to a certain extent, thereby improving the accuracy of determining the distribution lines in the distribution network including those with ground faults, and further improving the accuracy of determining the ground fault in the distribution network.

[0105] Among them, by setting a voltage threshold, the influence of external interference factors can be excluded to a certain extent, thereby improving the accuracy of determining the distribution lines in the distribution network including those with ground faults, and further improving the accuracy of determining the ground fault in the distribution network.

[0106] In a possible embodiment, the second fault detection requirement also indicates a first zero-sequence voltage threshold. The first zero-sequence voltage threshold is used to compare with the zero-sequence voltage to determine the ground fault detection result of the corresponding distribution line when the first zero-sequence current is less than the zero-sequence current threshold.

[0107] Among them, the first zero-sequence voltage threshold is less than the second zero-sequence voltage threshold.

[0108] Specifically, for the description of the first zero-sequence voltage threshold, reference can be made to the description in step S201, which will not be elaborated here.

[0109] Among them, since the first zero-sequence voltage threshold is the zero-sequence voltage threshold set when further determining whether there is a grounding fault in the process of determining the distribution line after determining that the distribution network needs to perform grounding fault detection, and based on Figure 2 the description in the illustrated embodiment, if the zero-sequence voltage is less than the first zero-sequence voltage threshold, there is still a situation where the distribution line has a grounding fault. Therefore, the first zero-sequence voltage threshold can be set to be less than the second zero-sequence voltage threshold to improve the accuracy of determining whether the distribution network needs to perform grounding fault detection, and further improve the accuracy and efficiency of the grounding fault detection of the distribution network.

[0110] In a possible embodiment, the first current transformer and the second current transformer satisfy at least one of the following:

[0111] The turns ratio of the first current transformer is greater than the first turns ratio threshold, and the turns ratio of the second current transformer is less than the second turns ratio threshold. Among them, the first turns ratio threshold is greater than the second turns ratio threshold.

[0112] The ratio between the turns ratio of the first current transformer and the turns ratio of the second current transformer is greater than a preset ratio threshold.

[0113] The first current transformer is a phase current transformer. The second current transformer is a zero-sequence current transformer.

[0114] Specifically, based on the description in step S101, the turns ratio of the first current transformer is greater than the turns ratio of the second current transformer to avoid the interference of the saturation and accuracy of the current transformer and improve the accuracy and efficiency of the grounding fault detection of the distribution network.

[0115] However, if the gap between the turns ratio of the first current transformer and the turns ratio of the second current transformer is not large enough, it will cause an incomplete avoidance of the interference of the saturation and accuracy of the current transformer. Therefore, the gap between the turns ratio of the first current transformer and the turns ratio of the second current transformer can be increased by setting the turns ratio of the first current transformer to be greater than the first turns ratio threshold and setting the turns ratio of the second current transformer to be less than the second turns ratio threshold. Among them, since the turns ratio of the first current transformer is greater than the turns ratio of the second current transformer, the first turns ratio threshold is greater than the second turns ratio threshold. Optionally, the first turns ratio threshold can be 300, and the second turns ratio threshold can be 30.

[0116] Alternatively, the difference between the transformation ratio of the first current transformer and that of the second current transformer can also be increased by setting the ratio between the transformation ratio of the first current transformer and that of the second current transformer to be greater than a preset ratio threshold. Optionally, the ratio threshold can be 10:1.

[0117] Among them, a phase current transformer is an electrical device that transforms a large current into a small current according to a certain ratio, and is mainly used for the monitoring, control, and protection of power systems. Its core function is to provide a small current signal proportional to the primary side current for measuring instruments and relay protection devices, so as to achieve safe and accurate monitoring and control of the power system; a zero-sequence current transformer is a device used to monitor and protect the unbalanced current in a power system. It mainly realizes the monitoring and protection functions by detecting the zero-sequence component of the current. When an unbalanced phenomenon occurs in the power system, such as a fault or leakage in one phase, the zero-sequence current transformer can sense and record these abnormal current changes, so as to judge whether there is a fault in the system.

[0118] Specifically, based on the above description of the phase current transformer and the zero-sequence current transformer, compared with the zero-sequence current transformer, the transformation ratio of the phase current transformer can be set to a larger value. Therefore, by setting the first current transformer as a phase current transformer and the second current transformer as a zero-sequence current transformer, the difference between the transformation ratio of the first current transformer and that of the second current transformer can meet the requirements of the accuracy and efficiency of the grounding fault detection in the current distribution network, that is, the requirement of avoiding the interference of the saturation and accuracy of the current transformer.

[0119] Among them, if the difference between the transformation ratio of the first current transformer and that of the second current transformer is not large enough, it will cause an incomplete avoidance of the interference of the saturation and accuracy of the current transformer. In this application, by setting at least one of the transformation ratio threshold, the ratio threshold of the transformation ratio, the type of the current transformer, etc., the difference between the transformation ratio of the first current transformer and that of the second current transformer is increased, so as to improve the accuracy of the detection of the first zero-sequence current and the second zero-sequence current, and further improve the accuracy and efficiency of the grounding fault detection in the distribution network.

[0120] Figure 4 The following is a schematic structural diagram of the device for determining the grounding fault of the distribution network provided by this application, as Figure 4 shown, the device 40 for determining the grounding fault of the distribution network provided in this embodiment includes:

[0121] An acquisition module 401 is configured to acquire a first zero-sequence current and a second zero-sequence current of each distribution line in the distribution network in response to the zero-sequence voltage of the bus in the distribution network satisfying a first fault detection requirement; wherein, the first fault detection requirement is used to determine whether the distribution network needs to perform a ground fault detection; wherein, the first zero-sequence current is obtained based on a first current transformer, and the second zero-sequence current is obtained based on a second current transformer; the transformation ratio of the first current transformer is greater than that of the second current transformer;

[0122] A determination module 402 is configured to determine that the corresponding distribution line has a ground fault if it is determined that the first zero-sequence current is greater than or equal to a zero-sequence current threshold; wherein, the zero-sequence current threshold is used for comparison processing with the first zero-sequence current to determine the ground fault detection result of the corresponding distribution line; the zero-sequence current threshold is indicated by a second fault detection requirement; the second fault detection requirement is used to determine whether the distribution line has a ground fault; if it is determined that the first zero-sequence current is less than the zero-sequence current threshold, at least one of the zero-sequence voltage and the second zero-sequence current is analyzed based on the second fault detection requirement to determine the ground fault detection result of the corresponding distribution line.

[0123] In a possible embodiment, the second fault detection requirement further indicates a first zero-sequence voltage threshold; wherein, the first zero-sequence voltage threshold is used for comparison processing with the zero-sequence voltage when the first zero-sequence current is less than the zero-sequence current threshold to determine the ground fault detection result of the corresponding distribution line; the determination module 402 is specifically configured to determine that the corresponding distribution line does not have a ground fault if it is determined that the zero-sequence voltage is greater than or equal to the first zero-sequence voltage threshold; if it is determined that the zero-sequence voltage is less than the first zero-sequence voltage threshold, phase comparison processing is performed on the zero-sequence voltage and the second zero-sequence current based on the second fault detection requirement to determine the ground fault detection result of the corresponding distribution line.

[0124] In a possible embodiment, the second fault detection requirement further indicates a phase threshold range; wherein, the phase threshold range is used for phase comparison processing when the first zero-sequence current is less than the zero-sequence current threshold and the zero-sequence voltage is less than the first zero-sequence voltage threshold to determine the ground fault detection result of the corresponding distribution line; the determination module 402 is further specifically configured to take the phase of the zero-sequence voltage as a reference phase and obtain the phase of the second zero-sequence current; if it is determined that the phase of the second zero-sequence current is within the phase threshold range, it is determined that the corresponding distribution line has a ground fault; otherwise, it is determined that the corresponding distribution line does not have a ground fault.

[0125] In a possible embodiment, the first fault detection requirement indicates a second zero-sequence voltage threshold; wherein, the second zero-sequence voltage threshold is used to compare with the zero-sequence voltage for processing to determine whether the distribution network needs to perform ground fault detection; wherein, if the zero-sequence voltage is greater than or equal to the second zero-sequence voltage threshold, it is determined that the distribution network needs to perform ground fault detection.

[0126] In a possible embodiment, the second fault detection requirement further indicates a first zero-sequence voltage threshold; wherein, the first zero-sequence voltage threshold is used to compare with the zero-sequence voltage for processing to determine the ground fault detection result of the corresponding distribution line when the first zero-sequence current is less than the zero-sequence current threshold; wherein, the first zero-sequence voltage threshold is less than the second zero-sequence voltage threshold. [[ID= 4]]

[0127] In a possible embodiment, the first current transformer and the second current transformer satisfy at least one of the following: the turns ratio of the first current transformer is greater than the first turns ratio threshold, and the turns ratio of the second current transformer is less than the second turns ratio threshold; wherein, the first turns ratio threshold is greater than the second turns ratio threshold; the ratio between the turns ratio of the first current transformer and the turns ratio of the second current transformer is greater than a preset ratio threshold; the first current transformer is a phase current transformer; the second current transformer is a zero-sequence current transformer.

[0128] The device for determining the ground fault of the distribution network provided in this embodiment can execute the method provided in the above method embodiment, and its implementation principle and technical effect are similar, which will not be elaborated here in this embodiment.

[0129] Figure 5 This is a schematic structural diagram of the electronic device provided in this application. As Figure 5 shown, the electronic device 50 provided in this embodiment includes: at least one processor 501 and a memory 502. Optionally, the electronic device 50 further includes a communication component 503. Wherein, the processor 501, the memory 502, and the communication component 503 are connected through a bus 504.

[0130] In the specific implementation process, at least one processor 501 executes the computer execution instructions stored in the memory 502, so that at least one processor 501 executes the above method.

[0131] The specific implementation process of the processor 501 can refer to the above method embodiment, and its implementation principle and technical effect are similar, which will not be elaborated here in this embodiment.

[0132] In the above embodiments, it should be understood that the processor may be a central processing unit (CPU for short), or other general-purpose processors, digital signal processors (DSP for short), application specific integrated circuits (ASIC for short), etc. The general-purpose processor may be a microprocessor or any conventional processor, etc. The steps of the method disclosed in combination with the invention can be directly implemented by the execution of the hardware processor, or by the combination of hardware and software modules in the processor.

[0133] The memory may include a high-speed random access memory (RAM), and may also include non-volatile memory (NVM), such as at least one disk memory.

[0134] The bus may be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, an Extended Industry Standard Architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For the convenience of representation, the buses in the drawings of this application are not limited to only one bus or one type of bus.

[0135] This application also provides a computer program product, including a computer program, which implements the above method when executed by a processor.

[0136] This application also provides a computer-readable storage medium, in which computer-executable instructions are stored, and when the processor executes the computer-executable instructions, the above method is implemented.

[0137] The above-readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, a magnetic disk or an optical disc. The readable storage medium can be any available medium accessible by a general-purpose or special-purpose computer.

[0138] An exemplary readable storage medium is coupled to a processor, enabling the processor to read information from and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can be located in an Application Specific Integrated Circuits (ASIC). Of course, the processor and the readable storage medium can also exist as discrete components in a device.

[0139] The division of units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Additionally, the couplings or direct couplings or communication connections shown or discussed between each other can be through some interfaces. The indirect couplings or communication connections of devices or units can be in electrical, mechanical, or other forms.

[0140] The units described as separate components may or may not be physically separated. The components shown as units may or may not be physical units, that is, they can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0141] Furthermore, in each embodiment of the present invention, the functional units can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit.

[0142] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or a part of this technical solution can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods in each embodiment of the present invention. The aforementioned storage medium includes various media that can store program codes, such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs.

[0143] Those of ordinary skill in the art can understand that all or part of the steps of implementing the above method embodiments can be completed by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it performs the steps including those of the above method embodiments; and the aforementioned storage medium includes: various media such as ROM, RAM, magnetic disks, or optical discs that can store program codes.

[0144] Finally, it should be noted that: after considering the specification and practicing the invention disclosed herein, those skilled in the art will readily conceive of other embodiments of the present invention. The present invention is intended to cover any variations, uses, or adaptations of the present invention, which follow the general principles of the present invention and include known common knowledge or conventional technical means in the technical field not disclosed by the present invention. It is not limited to the exact structures described above and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present invention is only limited by the appended claims.

Claims

1. A method for determining a grounding fault in a distribution network, characterized in that, Including: In response to the zero-sequence voltage of the busbar in the distribution network satisfying the first fault detection requirement, obtaining the first zero-sequence current and the second zero-sequence current of each distribution line in the distribution network; Wherein, the first fault detection requirement is used to determine whether the distribution network needs to perform ground fault detection; wherein, the first zero-sequence current is obtained based on the first current transformer, and the second zero-sequence current is obtained based on the second current transformer; the transformation ratio of the first current transformer is greater than the transformation ratio of the second current transformer; If it is determined that the first zero-sequence current is greater than or equal to the zero-sequence current threshold, it is determined that the corresponding distribution line has a ground fault; wherein, the zero-sequence current threshold is used for comparison processing with the first zero-sequence current to determine the ground fault detection result of the corresponding distribution line; the zero-sequence current threshold is indicated by the second fault detection requirement; the second fault detection requirement is used to determine whether the distribution line has a ground fault; If it is determined that the first zero-sequence current is less than the zero-sequence current threshold, at least one of the zero-sequence voltage and the second zero-sequence current is analyzed based on the second fault detection requirement to determine the ground fault detection result of the corresponding distribution line.

2. The method according to claim 1, wherein The second fault detection requirement also indicates a first zero-sequence voltage threshold; wherein, the first zero-sequence voltage threshold is used for comparison processing with the zero-sequence voltage when the first zero-sequence current is less than the zero-sequence current threshold to determine the ground fault detection result of the corresponding distribution line; Analyzing at least one of the zero-sequence voltage and the second zero-sequence current based on the second fault detection requirement to determine the ground fault detection result of the corresponding distribution line, including: If it is determined that the zero-sequence voltage is greater than or equal to the first zero-sequence voltage threshold, it is determined that the corresponding distribution line does not have a ground fault; If it is determined that the zero-sequence voltage is less than the first zero-sequence voltage threshold, the zero-sequence voltage and the second zero-sequence current are subjected to phase comparison processing based on the second fault detection requirement to determine the ground fault detection result of the corresponding distribution line.

3. The method according to claim 2, characterized in that, The second fault detection requirement also indicates a phase threshold range; wherein, the phase threshold range is used for phase comparison processing when the first zero-sequence current is less than the zero-sequence current threshold and the zero-sequence voltage is less than the first zero-sequence voltage threshold to determine the ground fault detection result of the corresponding distribution line; Performing phase comparison processing on the zero-sequence voltage and the second zero-sequence current based on the second fault detection requirement to determine the ground fault detection result of the corresponding distribution line, including: Taking the phase of the zero-sequence voltage as the reference phase, and obtaining the phase of the second zero-sequence current; If it is determined that the phase of the second zero-sequence current is within the phase threshold range, it is determined that the corresponding distribution line has a ground fault; otherwise, it is determined that the corresponding distribution line does not have a ground fault.

4. The method according to claim 1, characterized in that, The first fault detection requirement indicates a second zero-sequence voltage threshold; wherein, the second zero-sequence voltage threshold is used to compare with the zero-sequence voltage to determine whether the distribution network needs to perform a ground fault detection; wherein, if the zero-sequence voltage is greater than or equal to the second zero-sequence voltage threshold, it is determined that the distribution network needs to perform a ground fault detection.

5. The method according to claim 4, characterized in that, The second fault detection requirement further indicates a first zero-sequence voltage threshold; wherein, the first zero-sequence voltage threshold is used to compare with the zero-sequence voltage when the first zero-sequence current is less than the zero-sequence current threshold to determine the ground fault detection result of the corresponding distribution line. Wherein, the first zero-sequence voltage threshold is less than the second zero-sequence voltage threshold.

6. The method according to any one of claims 1-5, characterized in that, The first current transformer and the second current transformer satisfy at least one of the following: The turns ratio of the first current transformer is greater than a first turns ratio threshold, and the turns ratio of the second current transformer is less than a second turns ratio threshold; wherein, the first turns ratio threshold is greater than the second turns ratio threshold. The ratio between the turns ratio of the first current transformer and the turns ratio of the second current transformer is greater than a preset ratio threshold. The first current transformer is a phase current transformer; the second current transformer is a zero-sequence current transformer.

7. An apparatus for determining a grounding fault in a distribution network, characterized in that, Comprising: An acquisition module, configured to acquire a first zero-sequence current and a second zero-sequence current of each distribution line in the distribution network in response to the zero-sequence voltage of the bus in the distribution network satisfying the first fault detection requirement; wherein, the first fault detection requirement is used to determine whether the distribution network needs to perform a ground fault detection; wherein, the first zero-sequence current is obtained based on a first current transformer, and the second zero-sequence current is obtained based on a second current transformer; the turns ratio of the first current transformer is greater than the turns ratio of the second current transformer. A determination module, configured to determine that there is a ground fault in the corresponding distribution line if it is determined that the first zero-sequence current is greater than or equal to the zero-sequence current threshold; wherein, the zero-sequence current threshold is used to compare with the first zero-sequence current to determine the ground fault detection result of the corresponding distribution line; the zero-sequence current threshold is indicated by the second fault detection requirement; the second fault detection requirement is used to determine whether there is a ground fault in the distribution line; if it is determined that the first zero-sequence current is less than the zero-sequence current threshold, at least one of the zero-sequence voltage and the second zero-sequence current is analyzed based on the second fault detection requirement to determine the ground fault detection result of the corresponding distribution line.

8. An electronic device, characterized in that, Comprising: A memory, a processor; The memory stores computer execution instructions; The processor executes the computer execution instructions stored in the memory, so that the processor executes the method according to any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer execution instructions, and when the computer execution instructions are executed by a processor, they are used to implement the method according to any one of claims 1-6.

10. A computer program product, characterized in that, Comprising a computer program, which when executed by a processor implements the method according to any one of claims 1-6.

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