Four-quadrant adaptive intelligent current protection method and system for power distribution network

Abstract

The invention discloses a four-quadrant adaptive intelligent current protection method and system for a power distribution network, and the method comprises the steps: determining a phase angle difference according to fault current data and fault voltage data; fault types and a target quadrant where the fault types are located in four quadrants of the power distribution network are determined through the phase angle difference, and the fault types comprise a resistive and inductive load user fault, a non-clean energy power generation user fault, a clean energy power generation user fault and a resistive and capacitive load user fault; the method comprises the steps of adopting overcurrent protection under the condition that fault current data is larger than a constant current value, and adopting overcurrent protection under the condition that the fault current data is larger than the constant current value, and performing overcurrent protection on line faults of different fault currents in different operation modes due to the fact that the power flow direction is changed after the operation modes are changed. According to the invention, the problem that reliable action cannot be realized due to different fault currents inside and outside the demarcation point of various power generation users can be perfectly solved, and the quickness and selectivity of fault protection of the power distribution network are effectively improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of distribution network protection technology, and in particular to a four-quadrant adaptive intelligent current protection method and system for a distribution network. Background Art

[0002] With the continuous development of society, the power system plays an important role in our daily life. It not only affects the user's electricity experience, but also has a profound impact on economic and social development. The safety protection of the distribution network is the premise of ensuring the stability of power supply. Unstable power supply will lead to the failure to meet the user's electricity demand, and even have an adverse impact on the normal production and life of the masses. Therefore, it is of great significance to carry out safety protection of the distribution network.

[0003] At present, overcurrent protection is usually used for the safety protection of distribution networks. Overcurrent protection is to protect the company's equipment from damage by cutting off the circuit or sending an alarm signal when the current exceeds the predetermined maximum value. However, when the overcurrent protection is used for current quick-break and time-limited current quick-break protection, the fault current limit values ​​are different due to the changes in the operating conditions of different types of enterprises, but the current setting value is fixed. It is impossible to adaptively adjust the maximum current limit value for the changes in the operating conditions of different types of enterprises. As a result, when a fault occurs in the distribution network, the overcurrent protection device cannot quickly lock and cut off the fault current, causing the company's equipment to be damaged due to excessive current. When the operation mode of the power grid changes, the flow changes, and the fault current value at the same point is different, resulting in unnecessary expansion of the fault power outage range, thereby affecting the stability of the power system.

[0004] Therefore, a method is urgently needed to solve the above problems. Summary of the invention

[0005] The embodiments of the present application provide a four-quadrant adaptive intelligent current protection method and system for a power distribution network, which are used to improve the stability of the power system.

[0006] To achieve the above objectives, the embodiments of the present application adopt the following technical solutions:

[0007] In a first aspect, a four-quadrant adaptive intelligent current protection method for a distribution network is provided, comprising:

[0008] Obtaining fault current data and fault voltage data of a target line in a distribution network at the time of a fault;

[0009] Determining the phase angle difference of the target line according to the fault current data and the fault voltage data;

[0010] Determine the fault type according to the fault current phase angle difference, and determine the target quadrant of the fault type in the four quadrants of the distribution network, the fault types including resistive and inductive load user faults, non-clean energy power generation user faults, clean energy power generation users, resistive and capacitive load user faults, and line faults after the power flow direction changes after the operation mode changes;

[0011] Determine whether the fault current data is greater than the current setting corresponding to the target quadrant, and if the fault current data is greater than the current setting, perform overcurrent protection on the target user fault, and perform overcurrent protection on the line fault with the same point fault due to different fault currents under different operating modes due to the change of the flow direction after the operating mode changes.

[0012] In a possible implementation manner of the first aspect, in the four quadrants of the distribution network, the resistive-inductive load users are located in the first quadrant of the four quadrants, the non-clean energy power generation users are located in the second quadrant of the four quadrants, the clean energy power generation users are located in the third quadrant of the four quadrants, and the resistive-capacitive load users are located in the fourth quadrant of the four quadrants. The resistive-inductive load users are used to input active power and reactive power to the distribution network, the non-clean energy power generation users are used to output active power and reactive power to the distribution network, the clean energy power generation users are used to output active power and reactive power to the distribution network, and the resistive-capacitive load users are used to input active power and reactive power to the distribution network;

[0013] Before acquiring the fault current data and the fault voltage data of the target line in the distribution network at the time of the fault, the method includes:

[0014] Acquire current data and voltage data of the distribution network in real time, and determine whether the distribution network has a fault according to the current data and the voltage data;

[0015] In the case where there is a fault in the distribution network, the step of acquiring the fault current data and the fault voltage data of the target line in the distribution network at the time of the fault is performed.

[0016] In a possible implementation manner of the first aspect, determining the phase angle difference of the target line according to the fault current data and the fault voltage data includes:

[0017] Obtaining an instantaneous power value of the distribution network at the moment of the fault through the fault current data and the fault voltage data, wherein the instantaneous power value includes reactive power and active power;

[0018] Based on the reactive power and the active power, determining an input value and an output value of the reactive power, and an input value and an output value of the active power;

[0019] Calculating the power factor of the target line at the fault moment through the input value and output value of the reactive power and the input value and output value of the active power;

[0020] The phase angle difference of the target line is obtained by using a preset phase angle formula and calculating according to the power factor.

[0021] In a possible implementation manner of the first aspect, determining whether the distribution network has a fault according to the current data and the voltage data includes:

[0022] Acquire historical sample current data and historical sample voltage data;

[0023] Constructing a historical current spectrum diagram and a historical voltage spectrum diagram according to the historical sample current data and the historical sample voltage data;

[0024] Constructing a real-time current spectrum diagram and a real-time voltage spectrum diagram according to the current data and the voltage data acquired in real time;

[0025] Extracting a historical current feature vector of the historical current spectrum graph and a historical voltage feature vector of the historical voltage spectrum graph;

[0026] Extracting a real-time current feature vector of the real-time current spectrum diagram and a real-time voltage feature vector of the real-time voltage spectrum diagram;

[0027] Calculating a first similarity between the historical current feature vector and the real-time current feature vector;

[0028] Calculating a second similarity between the historical voltage feature vector and the real-time voltage feature vector;

[0029] If either the first similarity or the second similarity is smaller than a preset similarity threshold, it is determined that a fault exists in the power distribution network.

[0030] In a possible implementation of the first aspect, the real-time current feature vector includes a current amplitude and a current phase, the real-time voltage feature vector includes a voltage amplitude and a voltage phase, and the voltage feature vector includes a voltage amplitude and a voltage phase. After constructing a real-time current spectrum diagram and a real-time voltage spectrum diagram using the current data and the voltage data acquired in real time, the method includes:

[0031] Judging whether there is signal interference in the real-time current spectrum diagram according to the current amplitude and the current phase of the real-time current spectrum diagram;

[0032] If the current amplitude in the real-time current spectrum diagram is greater than a preset reference amplitude and the offset value of the current phase is greater than a preset phase threshold, it is determined that there is signal interference in the real-time current spectrum diagram;

[0033] Using a preset spectrum correction method to correct the real-time current spectrum diagram;

[0034] Judging whether there is signal interference in the real-time voltage spectrum graph according to the voltage amplitude and the voltage phase of the real-time voltage spectrum graph;

[0035] If the voltage amplitude in the real-time voltage spectrum diagram is greater than a preset reference amplitude and the offset value of the voltage phase is greater than a preset phase threshold, it is determined that there is signal interference in the real-time voltage spectrum diagram;

[0036] The real-time voltage spectrum diagram is corrected using a preset spectrum correction step.

[0037] In a possible implementation manner of the first aspect, the method further includes:

[0038] Calculating the composite power of the fault line through the fault current data and the fault voltage data;

[0039] Determine a power range within which the composite power lies;

[0040] Determining a preliminary fault type and a preliminary fault severity through the power range;

[0041] Based on the preliminary fault type and the preliminary fault severity, dividing the target line to obtain a plurality of sub-lines;

[0042] A preset fault location technology is used for each of the sub-circuits to determine the faulty sub-circuits and the fault location in the faulty sub-circuits.

[0043] In a possible implementation manner of the first aspect, before acquiring fault current data of a target line in the distribution network at the time of a fault, the method further includes:

[0044] Acquire a terminal node and a branch node in the distribution line of the target phase, wherein the branch node is located at a connection point between a branch line of the distribution line and a main line of the distribution line, and the terminal node is located at a connection point between a branch line of the distribution line and a load device;

[0045] The terminal node and the branch node constitute a section of the distribution line, the section of the distribution line includes a main line section and a branch line section, the line between the terminal node and the branch node is the branch line section, and the line between the branch node and the adjacent branch node is the main line section;

[0046] Determining the impact degree of each of the sections, and determining at least one target route according to the impact degree;

[0047] Determining the fault type according to the fault current phase angle difference, and determining the target quadrant of the fault type in the four quadrants of the distribution network, includes:

[0048] Determine a preset angle range where the phase angle difference is located, and determine a user fault type corresponding to the target line through the preset angle range;

[0049] According to the user fault type, a target quadrant corresponding to the user type is determined in the four quadrants of the power distribution network.

[0050] In a possible implementation manner of the first aspect, determining the influence degree of each of the sections, and determining at least one target route according to the influence degree, includes:

[0051] Obtaining the transmission power of each of the sections at the time of the fault;

[0052] Comparing each of the transmission powers with a preset reference power, marking the section exceeding the preset reference power, and obtaining an over-reference power section;

[0053] Comparing the transmission power of each section at the time of the fault with a preset reference power, marking the section that does not exceed the preset reference power, and obtaining a section that does not exceed the reference power;

[0054] Determine the difference between each of the super-reference power sections and a preset reference power to obtain a first power value set;

[0055] Determine the difference between each of the power sections that does not exceed the reference power and exceeds the preset reference power, and obtain a second power value set;

[0056] The first power number set and the second power number set form a matrix, wherein a row vector in the matrix represents each of the segments, and a column vector in the matrix is ​​formed by the first power number set and the second power number set;

[0057] Determining the impact level of each of the segments based on a preset risk assessment matrix;

[0058] Multiplying the influence degree of each of the sections by the power value of each of the sections corresponding to the matrix to obtain an influence degree matrix;

[0059] The sections exceeding the preset threshold in the influence degree matrix are marked, and the sections exceeding the preset threshold are used as target routes.

[0060] In a second aspect, the present application provides a machine-readable storage medium having instructions stored thereon, the instructions being used to enable a machine to execute the above-mentioned four-quadrant adaptive intelligent current protection method for a distribution network.

[0061] In a third aspect, the present application provides a four-quadrant adaptive intelligent current protection system for a distribution network, comprising:

[0062] a memory configured to store instructions; and

[0063] The processor is configured to call the instructions from the memory and implement the above-mentioned four-quadrant adaptive intelligent current protection method for the distribution network when executing the instructions.

[0064] Through the above technical scheme, by obtaining the current data and voltage data of the distribution network and determining whether there is a fault in the distribution network, the fault of the distribution network can be effectively monitored, and the abnormal situation in the distribution network can be discovered in time, so as to take measures in advance to prevent the occurrence of the fault. In the case of a fault in the distribution network, the fault location is determined, and the fault location of the distribution network can be obtained in time and accurately, reducing the time for troubleshooting the distribution network and reducing the economic losses caused by power outages. Among them, the four quadrants of the distribution network are divided based on the user type. By determining the fault location, it is possible to quickly identify the target user affected by the fault, and determine the target quadrant where the target user is located in the four quadrants of the distribution network, which can optimize the resource scheduling and allocation of the distribution network and improve the maintenance efficiency of the distribution network. Determine the current setting value of the target quadrant. When the fault current is greater than the current setting value of the target quadrant, take overcurrent protection for the target user in the target quadrant. Through overcurrent protection, the faulty equipment of the target user is isolated in time, which can prevent the fault from spreading in the power grid, reduce the impact of the fault on the overall operation of the power grid, and ensure the stability of the power system operation.

[0065] Other features and advantages of the embodiments of the present application will be described in detail in the subsequent specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] Figure 1 A schematic diagram of a flow chart of a four-quadrant adaptive intelligent current protection method for a distribution network provided in an embodiment of the present application;

[0067] Figure 2 A schematic diagram of a four-quadrant distribution network provided in an embodiment of the present application;

[0068] Figure 3 A schematic diagram of the structure of a main line section and a branch line section of a distribution network provided in an embodiment of the present application. DETAILED DESCRIPTION

[0069] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the specific implementation methods described herein are only used to illustrate and explain the embodiments of the present application, and are not used to limit the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0070] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0071] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present application, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0072] Figure 1 The following schematically shows a flow chart of a four-quadrant adaptive intelligent current protection method for a distribution network according to an embodiment of the present application. Figure 1 As shown, an embodiment of the present application provides a four-quadrant adaptive intelligent current protection method for a distribution network, which may include the following steps.

[0073] S110, acquiring fault current data and fault voltage data of a target line in the distribution network at the time of a fault;

[0074] S120, determining the phase angle difference of the target line according to the fault current data and the fault voltage data;

[0075] S130, determining the fault type according to the fault current phase angle difference, and determining the target quadrant of the fault type in the four quadrants of the distribution network, the fault types including resistive inductive load user faults, non-clean energy power generation user faults, clean energy power generation users, resistive and capacitive load user faults, and line faults after the power flow direction changes after the operation mode changes;

[0076] S140, determining whether the fault current data is greater than the current setting corresponding to the target quadrant, and in the case where the fault current data is greater than the current setting, performing overcurrent protection on the target user fault, and performing overcurrent protection on the line fault where the direction of the power flow changes after the operation mode changes and the fault current is different under different operation modes at the same point.

[0077] The fault current data and fault voltage data of the target line in the distribution network at the time of the fault can be obtained through smart meters and sensors, which can be current sensors and voltage sensors. Through the data of smart meters and sensors, the operating status of the distribution line can be monitored in real time, and parameters such as current, voltage, power factor, etc. can be monitored in real time, including the monitoring of fault current and fault voltage.

[0078] After obtaining the fault current data and fault voltage data of the target line in the distribution network at the time of the fault, the phase angle difference of the target line is determined according to the fault current data and the fault voltage data. Specifically, the instantaneous power value of the distribution network at the time of the fault is first obtained through the fault current data and the fault voltage data, wherein the instantaneous power value includes reactive power and active power. The instantaneous power value of the distribution network at the time of the fault can be determined by measuring equipment such as current transformers and voltage transformers, and appropriate signal processing such as filtering and amplifying signals may be required to improve the accuracy of the measurement. Reactive power refers to the electric power required to establish a magnetic field when components such as inductors and capacitors in electrical equipment are working. It is a form of electrical energy, but it cannot do work and cannot be consumed. Active power refers to the electric power required to keep the equipment running, that is, the electric power that converts electric energy into other forms of energy. Subsequently, based on the reactive power and the active power, the input value and the output value of the reactive power, as well as the input value and the output value of the active power are determined; and the power factor at the moment of the fault is calculated by the active power formula or the reactive power formula, and the phase angle difference of the target line is obtained by the preset phase angle formula and according to the power factor calculation.

[0079] Figure 2 A schematic diagram of the structure of a four-quadrant distribution network according to an embodiment of the present application is schematically shown, as shown in the figure: the first quadrant is for resistive and inductive load users, the second quadrant is for non-clean energy power generation users, the third quadrant is for clean energy power generation users, and the fourth quadrant is for resistive and capacitive load users;

[0080] After determining the phase angle difference of the target line, the fault type is determined according to the fault current phase angle difference. In this embodiment, the fault types include resistive inductive load user faults, non-clean energy power generation user faults, clean energy power generation user faults, resistive and capacitive load user faults, and line faults after the flow direction changes after the operation mode changes. The phase angle difference refers to the displacement difference between two waves with the same frequency but different phases. In alternating current, it specifically refers to the phase difference between two currents or voltages with the same frequency. Line faults after the flow direction changes after the operation mode changes refer to when the operation mode of the power system changes, such as power switching or load transfer, which will affect the power distribution and flow direction in the system. For example, when a power source is cut off, the power originally provided by the power source will be redistributed, which may cause the flow direction of other lines to change. In this embodiment, the four quadrants of the distribution network are divided based on user types, which include resistive inductive load users, non-clean energy power generation users, clean energy power generation users and resistive capacitive load users. The resistive inductive load users are located in the first quadrant of the four quadrants. The first quadrant is for inputting active power and inputting reactive power. The users are resistive inductive loads and need to obtain electric energy and reactive power from the power grid; the non-clean energy power generation users are located in the second quadrant of the four quadrants. The second quadrant is for outputting active power but inputting reactive power, and sending active power back to the power grid but still needing to obtain reactive power from the power grid; the clean energy power generation users are located in the third quadrant of the four quadrants. The third quadrant is for outputting active power and outputting reactive power, and sending electric energy and reactive power back to the power grid; the resistive capacitive load users are located in the fourth quadrant of the four quadrants. The fourth quadrant is for inputting active power but outputting reactive power. The users are resistive capacitive loads and obtain active power from the power grid but send reactive power back to the power grid. The fourth quadrant is for inputting active power but outputting reactive power. The user is a resistive and capacitive load, which obtains active power from the power grid but returns reactive power to the power grid. According to the fault current phase angle difference, the fault type is determined, and the target quadrant of the fault type in the four quadrants of the distribution network is determined. That is to say, the fault type is obtained by comparing the fault current phase angle difference with the known fault type characteristics. For example, in the case of a symmetrical fault, the phase angle difference of the three-phase voltage and current is 120°, and the phase angle of the positive sequence component is consistent, and the phase angle of the negative sequence component is 0°. In the case of an asymmetrical fault, the phase angle difference of the three-phase voltage and current is not 120°, and the phase angles of the positive sequence component and the negative sequence component are different. Common asymmetrical fault types include single-phase grounding faults, two-phase short circuit faults, etc. Asymmetrical faults refer to faults in which the three-phase voltage and current are asymmetrical in amplitude or phase. This is because an asymmetrical fault will cause the magnitude and phase of the three-phase current to no longer be equal or differ by a fixed angle, so the phase angle difference also presents the characteristics of asymmetrical distribution.If the phase angle difference meets the characteristics of a symmetrical fault, for example, the three-phase phase angle difference is 120°, and the phase angles of the positive sequence components are consistent and the phase angle of the negative sequence component is 0°, then it is judged as a symmetrical fault. If the phase angle difference does not meet the characteristics of a symmetrical fault, further analysis is performed to determine whether it meets the characteristics of an asymmetrical fault.

[0081] After determining the fault type, determine the fault type and determine the target quadrant of the fault type in the four quadrants of the distribution network. Specifically, determine the preset angle range where the phase angle difference is located, and determine the user type corresponding to the target line through the preset angle range. After obtaining the user type, determine the target quadrant corresponding to the user type in the four quadrants of the distribution network. For example, when the phase difference is between 0° and 90° and the power factor is greater than 0, the target user is in the first quadrant; when the phase difference is between -90° and 0° and the power factor is less than 0, it means that active power is emitted but reactive power is absorbed, and the target user is in the second quadrant; when the phase difference is between -90° and -180° and the power factor is less than 0, it means that active and reactive power are emitted, and the target user is in the third quadrant; when the phase difference is between 0° and 90° and the power factor is greater than 0, but the current direction is opposite to the voltage direction, the target user is in the fourth quadrant.

[0082] Determine whether the fault current data is greater than the current setting corresponding to the target quadrant, and when the fault current data is greater than the current setting, perform overcurrent protection on the target user fault, and perform overcurrent protection on the line fault with the same point fault due to different fault currents under different operating modes after the flow direction changes after the operation mode changes, that is, determine whether the fault current data is greater than the current setting corresponding to the target quadrant, and when the fault current data is greater than the current setting, perform overcurrent protection on the target user in the target quadrant. Overcurrent protection means that when the current flowing through the protected element exceeds the preset value, the protection device is activated to ensure the selectivity of the action, so that the circuit breaker trips or sends an alarm signal, thereby protecting the circuit and electrical equipment from damage. That is to say, when the distribution line fails, such as short circuit, overload, etc., the current value caused by the abnormality is determined. Whether the abnormal current value is greater than the maximum current preset value in the target quadrant, when the abnormal current value is greater than the maximum current preset value, the current protection device is taken. That is to say, when the current flowing through the protected element exceeds the preset value, the protection device is activated to cut off or limit the current, thereby protecting the equipment and circuit from damage.

[0083] Through the above technical scheme, by obtaining the current data and voltage data of the distribution network and determining whether there is a fault in the distribution network, the fault of the distribution network can be effectively monitored, and the abnormal situation in the distribution network can be discovered in time, so as to take measures in advance to prevent the occurrence of the fault. In the case of a fault in the distribution network, the fault location is determined, and the fault location of the distribution network can be obtained in time and accurately, reducing the time for troubleshooting the distribution network and reducing the economic losses caused by power outages. Among them, the four quadrants of the distribution network are divided based on the user type. By determining the fault location, it is possible to quickly identify the target user affected by the fault, and determine the target quadrant where the target user is located in the four quadrants of the distribution network, which can optimize the resource scheduling and allocation of the distribution network and improve the maintenance efficiency of the distribution network. Determine the current setting value of the target quadrant. When the fault current is greater than the current setting value of the target quadrant, take overcurrent protection for the target user in the target quadrant. Through overcurrent protection, the faulty equipment of the target user is isolated in time, which can prevent the fault from spreading in the power grid, reduce the impact of the fault on the overall operation of the power grid, and ensure the stability of the power system operation.

[0084] In one implementation manner of this embodiment, before acquiring the fault current data and the fault voltage data of the distribution network, the method includes:

[0085] S210, acquiring current data and voltage data of the distribution network in real time, and determining whether there is a fault in the distribution network according to the current data and voltage data;

[0086] S220: When there is a fault in the distribution network, execute the step of obtaining fault current data and fault voltage data of the distribution network.

[0087] The current data and voltage data of the distribution network are obtained in real time. The current data and voltage data of the distribution network can be collected through the data acquisition system. The data acquisition system includes a measuring unit, an acquisition unit, a synchronization unit and a post-processing unit. The measuring unit is mainly composed of a voltage divider, a current sensor and a voltage sensor, which are used to convert large current signals and high voltages in the circuit into small analog signals; the acquisition unit is responsible for receiving the small analog signals transmitted by the measuring unit and converting them into digital signals for storage and transmission; the synchronization unit is used to maintain the synchronization between the post-processing unit and the acquisition unit to ensure the accuracy and consistency of the data; the post-processing unit processes and analyzes the collected data to generate corresponding current and voltage data reports; after the current data and voltage data of the distribution network are collected by the data acquisition system, it is determined whether there is a fault in the distribution network. In this embodiment In the example, the failure of the distribution network refers to the line failure of the distribution network. The line failure of the distribution network is generally caused by line disconnection, line short circuit, line grounding, line overload and phase-to-phase short circuit caused by foreign objects; line disconnection may be caused by line aging, insulation damage, weather influence, etc.; line short circuit mainly occurs between various phases, and is caused by multiple different phases being grounded; line grounding is usually caused by the insulation decline and breakdown of the user's drop-type fuse, lightning arrester or wall bushing; line overload refers to the phenomenon that the load is too large or the current is too large, causing the equipment to burn out or personal safety to be threatened; the phase-to-phase short circuit caused by foreign objects may be caused by foreign objects, such as plastic paper with aluminum foil, tarpaulin paper with aluminum foil, broken TV antennas near the line, broken branches, discarded recording tapes, etc. These materials may be blown onto the line due to strong winds, which may cause phase-to-phase short circuits. Whether there is a fault in the distribution network is determined based on the current data and voltage data, mainly through the current spectrum diagram and the voltage spectrum diagram. Specifically, the spectrum diagram is constructed by obtaining historical current data and historical voltage data, and the spectrum diagram is constructed by real-time current data and voltage data. The similarity between the historical current spectrum diagram and the real-time current spectrum diagram, and the similarity between the historical voltage spectrum diagram and the real-time voltage spectrum diagram are compared respectively, so as to determine whether there is a fault in the distribution network.

[0088] When there is a fault in the distribution network, the fault current data and fault voltage data can be obtained through smart meters and sensors. Through the data of smart meters and sensors, the operating status of the distribution line can be monitored in real time, and the parameters such as current, voltage, power factor, etc. can be monitored in real time, including the monitoring of fault current and fault voltage. After obtaining the fault current data and fault voltage data, the fault location is determined based on the fault current data and fault voltage data, which can be obtained by calculating the composite power of the fault line. In this embodiment, the composite power is the apparent power, which is used to describe the total power in the AC circuit, including active power and reactive power. First, determine the apparent power range of the line, and divide the fault line based on the preliminary fault type and the preliminary fault severity to obtain multiple sub-lines; second, after determining the multiple sub-lines, determine the fault location in the target fault line based on a preset fault location technology. In this embodiment, the preset fault location technology refers to a set of automatic and efficient fault point detection and positioning systems based on fault indicator technology, GSM communication technology and GIS technology. It is mainly used for the detection and positioning of various fault points in the distribution system. Through the preset fault location technology, the longitude and latitude coordinates of the fault location are determined in the sub-line, thereby obtaining the fault location.

[0089] By acquiring the current data and voltage data of the distribution network in real time and determining whether there is a fault in the distribution network based on the current data and voltage data, when there is a fault in the distribution network, executing the steps of acquiring the fault current data and fault voltage data of the distribution network, the abnormal state of the distribution network can be detected at the first time, which helps to reduce the impact of the fault on the distribution network and users and improve the reliability and stability of the system.

[0090] In one implementation of this embodiment, determining the phase angle difference of the target line according to the fault current data and the fault voltage data includes:

[0091] S310, obtaining an instantaneous power value of the distribution network at the time of the fault through the fault current data and the fault voltage data, wherein the instantaneous power value includes reactive power and active power;

[0092] S320, determining an input value and an output value of reactive power, and an input value and an output value of active power based on reactive power and active power;

[0093] S330, calculating the power factor of the target line at the time of the fault through the input value and output value of the reactive power and the input value and output value of the active power;

[0094] S340: Using a preset phase angle formula, calculate the phase angle difference of the target line according to the power factor.

[0095] According to the fault current data and the fault voltage data, the phase angle difference of the target line is determined. Specifically, first, the instantaneous power value of the distribution network at the time of the fault is obtained through the fault current data and the fault voltage data, wherein the instantaneous power value includes reactive power and active power, wherein the instantaneous power value includes reactive power and active power, wherein the instantaneous power value includes reactive power and active power, and active power refers to the electric power required to keep the equipment running, that is, the electric power that converts electric energy into other forms of energy. Reactive power refers to the electric power required to establish a magnetic field when components such as inductors and capacitors in electrical equipment are working. It is a form of electric energy, but it cannot do work and cannot be consumed. In other words, to determine the instantaneous power value at the time of the fault in the distribution network, it can be obtained through measuring equipment such as current transformers and voltage transformers to improve the accuracy of the measurement. The instantaneous values ​​of the current and voltage obtained are calculated using the formula for instantaneous power. The calculation formula for instantaneous power is:

[0096] p(t)=v(t)×i(t)

[0097] Where p(t) is the instantaneous power, v(t) is the instantaneous voltage, and i(t) is the instantaneous current;

[0098] The instantaneous power value of the distribution network at the moment of fault is obtained through the calculation formula of instantaneous power.

[0099] After obtaining the instantaneous power value, the input value and output value of reactive power, as well as the input value and output value of active power are determined based on reactive power and active power, that is, the input value and output value of reactive power, as well as the input value and output value of active power are calculated respectively using the instantaneous power calculation formula. In the power system, when the device or load needs to absorb reactive power from the power grid, there is an input of reactive power. For example, inductive loads such as motors absorb reactive power during operation, and these reactive powers are used to establish and maintain magnetic fields in electromagnetic fields. On the contrary, when the device or load emits reactive power to the power grid, there is an output of reactive power. For example, capacitive loads such as capacitors emit reactive power during charging and discharging. The input value of active power refers to the power actually absorbed by the device or load from the power grid, and the electric energy provided by the power grid to the device or load is used to drive the device to operate or meet the energy consumption requirements of the load. In the power system, the input value of active power is usually obtained by measuring the voltage across the device or load and the current flowing through, and calculating their product. The output value of active power refers to the effective power actually output by the device or load per unit time. This is the part where the device or load converts the electrical energy provided by the power grid into other forms of energy and performs work externally.

[0100] The phase angle difference at the time of the fault is calculated through the input and output values ​​of reactive power and the input and output values ​​of active power. The phase angle difference refers to the displacement difference between two waves with the same frequency but different phases. In alternating current, it specifically refers to the phase difference between two currents or voltages with the same frequency. Specifically, the phase angle difference can be calculated based on the corresponding input and output values ​​of power in the four quadrants. For example, the power factor can be calculated through the formula of active power. The formula of active power is as follows:

[0101]

[0102] Among them, P is the active power, which represents the actual power consumed by the circuit, U is the effective value of the voltage, I is the effective value of the current, and φ is the phase angle difference between the voltage and current, also known as the power factor angle.

[0103] The power factor is calculated by the reactive power formula, and the reactive power formula is as follows:

[0104]

[0105] Among them, Q is reactive power, which represents the power that exchanges energy with the power supply due to the energy storage function of the inductor or capacitor, U is the effective value of the voltage, I is the effective value of the current, and φ is the phase angle difference between the voltage and the current.

[0106] By using the active power formula and the reactive power formula, the corresponding power factor angle is calculated in the target quadrant based on the power input and output mode corresponding to the target quadrant and the input and output values.

[0107] The preset phase angle formula is used to calculate the phase angle difference of the target line according to the power factor angle. The preset phase angle formula is:

[0108]

[0109] Where θ represents the phase angle difference, Indicates power factor;

[0110] The power factor is obtained by calculation, and the phase angle difference of the target line is calculated using a preset phase angle formula.

[0111] By using the real-time current spectrum features and real-time voltage spectrum features to determine the fault time of the distribution network and the instantaneous power at the time of the fault, the power flow at the time of the fault can be accurately obtained, and the fault location can be quickly located. By using the phase angle difference, the target quadrant where the target user is located can be determined. Based on the target quadrant of the target user in the four quadrants of the distribution network, a targeted fault repair strategy can be formulated, which helps to ensure the effectiveness and safety of measures taken on the faulty line.

[0112] In one implementation of this embodiment, determining whether there is a fault in the distribution network according to the current data and the voltage data includes:

[0113] S410, obtaining historical sample current data and historical sample voltage data;

[0114] S420, constructing a historical current spectrum diagram and a historical voltage spectrum diagram according to the historical sample current data and the historical sample voltage data;

[0115] S430, constructing a real-time current spectrum diagram and a real-time voltage spectrum diagram according to the current data and voltage data acquired in real time;

[0116] S440, extracting a historical current feature vector of the historical current spectrum graph and a historical voltage feature vector of the historical voltage spectrum graph;

[0117] S450, extracting a real-time current feature vector of the real-time current spectrum graph and a real-time voltage feature vector of the real-time voltage spectrum graph;

[0118] S460, calculating a first similarity between the historical current feature vector and the real-time current feature vector;

[0119] S470, calculating a second similarity between the historical voltage feature vector and the real-time voltage feature vector;

[0120] S480: If any one of the first similarity and the second similarity is less than a preset similarity threshold, it is determined that a fault exists in the distribution network.

[0121] First, obtain historical sample current data and historical sample voltage data through data acquisition software. By installing data acquisition software, you can collect current and voltage data from the power system in real time and automatically record historical data. For example, the HiWoo Cloud platform can seamlessly connect to various types of power distribution equipment, including transformers, switch cabinets, circuit breakers, etc., and collect and store the operating status parameters of the equipment in real time and accurately, such as current, voltage, temperature, humidity, etc.

[0122] After obtaining the historical sample current data and the historical sample voltage data, the historical sample current and the historical sample voltage data are used to construct a historical current spectrum diagram and a historical voltage spectrum diagram. The historical current spectrum diagram refers to a graphical representation of the distribution and intensity of the current signal at different frequencies in a certain period of time in the past and is recorded and analyzed. It can be obtained by using mathematical methods such as Fourier transform by converting the current signal from the time domain to the frequency domain. The historical voltage spectrum diagram refers to a graphical representation of the distribution and intensity of the voltage signal at different frequencies in a certain period of time in the past and is recorded and analyzed. It is usually represented as a visual display of the voltage signal in the frequency domain, with the horizontal axis representing the frequency and the vertical axis representing the voltage amplitude or power at the corresponding frequency. The spectrum diagram can be obtained by Fourier transform, which is a mathematical method mainly used to convert functions from the time domain to the frequency domain and is commonly used in spectrum analysis in the field of signal processing. That is to say, the historical sample current and the historical sample voltage data are converted from the time domain to the frequency domain using Fourier transform to obtain the historical current spectrum diagram and the historical voltage spectrum diagram. In this embodiment, the historical current spectrum diagram is obtained by the historical sample current, and the historical voltage spectrum diagram is obtained by the historical sample voltage.

[0123] Secondly, a real-time current spectrum diagram and a real-time voltage spectrum diagram are constructed according to the current data and voltage data acquired in real time. The real-time current spectrum diagram shows the real-time distribution and intensity of the current signal at different frequencies. It is usually expressed as being obtained by converting the current signal from the time domain to the frequency domain in real time, and is implemented by relying on efficient algorithms such as fast Fourier transform. The real-time voltage spectrum diagram is used to show the real-time distribution and intensity of the voltage signal at different frequencies. It is usually expressed as being obtained by converting the voltage signal from the time domain to the frequency domain in real time, and is implemented by relying on efficient algorithms such as fast Fourier transform. The spectrum diagram can be obtained by Fourier transform, which is a mathematical method mainly used to convert functions from the time domain to the frequency domain and is commonly used in spectrum analysis in the field of signal processing. In other words, the current data and voltage data acquired in real time are converted from the time domain to the frequency domain using Fourier transform to obtain a real-time current spectrum diagram and a real-time voltage spectrum diagram. In this embodiment, the real-time current spectrum diagram is obtained by the current data acquired in real time, and the real-time voltage spectrum diagram is obtained by the voltage data acquired in real time.

[0124] After constructing the historical current spectrum graph and the historical voltage spectrum graph, the historical current feature vector of the historical current spectrum graph and the historical voltage feature vector of the historical voltage spectrum graph can be extracted through a neural network model. The neural network model has a convolution layer, a pooling layer, and a fully connected layer. The convolution layer can perform a convolution operation on the input data through a series of learnable convolution kernels to extract local features in the image. The local features can be features such as edges, textures, and shapes. The feature extraction of the spectrum graph of the historical current spectrum graph and the historical voltage spectrum graph is performed through the convolution layer in the convolutional neural network to determine the amplitude, frequency distribution, and amplitude feature vector of the historical current spectrum graph and the historical voltage spectrum graph.

[0125] Subsequently, the real-time current feature vector and the real-time voltage feature vector are extracted from the real-time current spectrum graph and the real-time voltage spectrum graph. A convolutional neural network can also be used. Similarly, the feature extraction of the spectrum graph is performed on the real-time current spectrum graph and the real-time voltage spectrum graph through the convolution layer in the convolutional neural network to determine the feature vectors of the intensity, frequency distribution and amplitude of the real-time current spectrum graph and the real-time voltage spectrum graph.

[0126] After determining the historical voltage feature vector, the historical current feature vector, the real-time voltage feature vector, and the real-time current feature vector, the first similarity between the historical current feature vector and the real-time current feature vector is calculated. In this embodiment, the first similarity refers to the similarity relationship between the historical current feature vector and the real-time current feature vector. The first similarity can be calculated by cosine similarity, which is an indicator for measuring the directional similarity of two vectors. The principle is based on the vector space model, representing documents or data items as vectors, and calculating the cosine values ​​between these vectors. The similarity is obtained by calculating the cosine value of the angle between the historical current feature vector and the real-time current feature vector through cosine similarity. When the cosine value is closer to 1, it means that the two feature vectors are more similar, and when the cosine value is closer to 0, it means that the two feature vectors are less similar.

[0127] The second similarity between the historical voltage feature vector and the real-time voltage feature vector is calculated. In this embodiment, the second similarity refers to the similarity relationship between the historical voltage feature vector and the real-time voltage feature vector. The second similarity can be calculated by cosine similarity, which is an indicator for measuring the directional similarity of two vectors. The principle is based on the vector space model, representing documents or data items as vectors, and calculating the cosine value between these vectors. The similarity is obtained by calculating the cosine value of the angle between the historical voltage feature vector and the real-time voltage feature vector through cosine similarity. When the cosine value is closer to 1, it means that the two feature vectors are more similar, and when the cosine value is closer to 0, it means that the two feature vectors are less similar.

[0128] After determining the first similarity and the second similarity, the first similarity and the second similarity are compared with a preset similarity threshold, which can be determined according to actual conditions. When one of the first similarity and the second similarity is less than the preset similarity threshold, for example, when the preset current similarity threshold is 80% and the preset voltage similarity threshold is 80%, and it is calculated that the similarity of either the first similarity or the second similarity is less than 80%, it is determined that there is a fault in the distribution network.

[0129] By converting current and voltage data into a spectrum, the frequency distribution and change trend of the data can be clearly seen, and small changes and anomalies in the current and voltage data can be captured, thereby improving the accuracy of fault detection. By calculating the similarity between historical feature vectors and real-time feature vectors, it is possible to determine that there is a fault in the distribution network and take effective measures in a timely manner, thereby improving the accuracy of fault detection and ensuring the stable operation of the power system.

[0130] In one implementation of this embodiment, the real-time current feature vector includes the current amplitude and the current phase, the real-time voltage feature vector includes the voltage amplitude and the voltage phase, and the voltage feature vector includes the voltage amplitude and the voltage phase. After the real-time current data and voltage data acquired in real time are constructed into a real-time current spectrum diagram and a real-time voltage spectrum diagram, the following steps are included:

[0131] S510, judging whether there is signal interference in the real-time current spectrum diagram according to the current amplitude and current phase of the real-time current spectrum diagram;

[0132] S520, if the current amplitude in the real-time current spectrum diagram is greater than the preset reference amplitude and the offset value of the current phase is greater than the preset phase threshold, it is determined that there is signal interference in the real-time current spectrum diagram;

[0133] S530, using a preset spectrum correction method to correct the real-time current spectrum diagram;

[0134] S540, judging whether there is signal interference in the real-time voltage spectrum graph according to the voltage amplitude and voltage phase of the real-time voltage spectrum graph;

[0135] S550, if the voltage amplitude in the real-time voltage spectrum diagram is greater than the preset reference amplitude and the voltage phase offset value is greater than the preset phase threshold, it is determined that there is signal interference in the real-time voltage spectrum diagram;

[0136] S560: Use a preset spectrum correction method to correct the real-time voltage spectrum diagram.

[0137] After constructing the real-time current spectrum graph and the real-time voltage spectrum graph with the current data and voltage data acquired in real time, first, the current amplitude and current phase of the real-time current spectrum graph are used to determine whether there is signal interference in the real-time current spectrum graph. Signal interference may generally be electromagnetic radiation interference. External electromagnetic fields may cause radiation interference to the current spectrum graph measuring equipment, such as radio waves, lightning, etc., which will have a certain impact on the current spectrum graph. In addition, when multiple signals are transmitted simultaneously, intermodulation effects may occur between them, generating new interference signals. This interference is particularly common in communication systems and may also affect the measurement of the current spectrum graph. In this embodiment, the electromagnetic radiation interference in the real-time current spectrum graph is mainly analyzed. When electromagnetic radiation interference appears in the current spectrum graph, the current spectrum graph will have a phase deviation, such as a phase delay or advance. The phase deviation may be manifested in the spectrum graph as a phase angle shift of each frequency component, and the phase relationship of the original signal is no longer maintained. The amplitude of the current spectrum graph may also have amplitude deviation. For example, magnetic radiation interference may appear as high-frequency noise or random noise. These noises will be superimposed on the original current signal, causing the amplitude in the spectrum graph to fluctuate or increase, causing the amplitude of some frequency components in the spectrum graph to increase and shift, while the amplitude of other frequency components may be underestimated. Therefore, when the current amplitude and current phase of the real-time current spectrum graph deviate, it is determined that there is signal interference in the real-time current spectrum graph. Specifically, if the current amplitude in the real-time current spectrum graph is greater than the preset reference amplitude and the offset value of the current phase is greater than the preset phase threshold, it is determined that there is signal interference in the real-time current spectrum graph. The preset threshold can be determined according to the actual situation. When there is electromagnetic radiation interference, the current amplitude will be greater than the preset reference amplitude. Since the interference signal is usually superimposed on the original signal, resulting in an increase in amplitude, when the value of the current amplitude offset is greater than the preset reference amplitude, it is determined that there is signal interference in the real-time current spectrum graph.

[0138] When there is signal interference in the real-time current spectrum diagram, a preset spectrum correction method is used to correct the real-time current spectrum diagram. In this embodiment, the preset spectrum correction method can be a smoothing method. The real-time current spectrum diagram can be corrected by the smoothing method. By smoothing the spectrum signal, the influence of noise on the spectrum signal can be reduced. The smoothing method is to give a weighted average to the actual data and the original predicted data continuously obtained, so that the prediction result is closer to the actual situation. By using the smoothing method to perform weighted averaging on the current signal data, the accuracy of the actual data obtained is improved, the interference of the electromagnetic radiation signal on the current signal is reduced, and the real-time current spectrum diagram is guaranteed to be more accurate, thereby correcting the real-time current spectrum diagram with interference.

[0139] After the real-time current spectrum diagram is corrected, the voltage amplitude and voltage phase of the real-time voltage spectrum diagram are used to determine whether there is signal interference in the real-time voltage spectrum diagram. The signal interference in the real-time voltage spectrum diagram generally includes electromagnetic interference, such as power frequency interference and radio frequency interference, and mutual interference between devices. For example, when multiple electronic devices work at the same time, the electromagnetic fields between them may interfere with each other. In this embodiment, the signal interference of the real-time voltage spectrum diagram is mainly to analyze the power frequency interference in the electromagnetic interference. The power frequency interference is generally the electromagnetic field radiation interference generated by the transmission and distribution system and the electric traction system. When electromagnetic field radiation interference occurs, the voltage amplitude in the real-time voltage spectrum diagram will increase. Electromagnetic field radiation interference is usually manifested as broadband noise or peaks of specific frequencies in the spectrum diagram. These interference signals will be superimposed on the original signal, resulting in an increase in the noise floor of the voltage spectrum diagram. Therefore, after the electromagnetic field radiation interference occurs, the voltage amplitude in the real-time voltage spectrum diagram will increase. At the same time, when electromagnetic field radiation interference occurs, the voltage phase in the real-time voltage spectrum graph will have a phase shift. Therefore, when the voltage amplitude and voltage phase of the real-time voltage spectrum graph deviate, it is determined that there is signal interference in the real-time voltage spectrum graph. Specifically, if the voltage amplitude in the real-time voltage spectrum graph is greater than the preset reference amplitude and the voltage phase offset value is greater than the preset phase threshold, it is determined that there is signal interference in the real-time voltage spectrum graph. The preset threshold can be determined according to actual conditions. When there is electromagnetic radiation interference, the voltage amplitude will be greater than the preset reference amplitude. Since the interference signal is usually superimposed on the original signal, resulting in an increase in amplitude, when the voltage amplitude offset value is greater than the preset reference amplitude, it is determined that there is signal interference in the real-time voltage spectrum graph.

[0140] When there is signal interference in the real-time voltage spectrum graph, a preset spectrum correction method is used to correct the real-time voltage spectrum graph. In this embodiment, the preset spectrum correction method can be a smoothing method. The real-time voltage spectrum graph can be corrected by the smoothing method. By smoothing the spectrum signal, the influence of noise on the spectrum signal can be reduced. The smoothing method is to give a weighted average to the actual data and the original predicted data continuously obtained, so that the prediction result is closer to the actual situation. By using the smoothing method to perform weighted averaging on the voltage signal data, the accuracy of the actual data obtained is improved, the interference of the electromagnetic radiation signal on the voltage signal is reduced, and the real-time voltage spectrum graph is guaranteed to be more accurate, thereby correcting the real-time voltage spectrum graph with interference.

[0141] By judging whether there is signal interference in the real-time current spectrum diagram and the real-time voltage spectrum diagram, and correcting the real-time current spectrum diagram and the real-time voltage spectrum diagram, these interference signals can be effectively reduced or eliminated, thereby improving the quality of voltage signals and current signals, enhancing system stability, optimizing data analysis and reducing maintenance costs, and ensuring the stable operation of the power system and the accuracy of data processing.

[0142] In one implementation of this embodiment, the method further includes:

[0143] S610, calculating the composite power of the fault line through the fault current data and the fault voltage data;

[0144] S612, determining a power range where the composite power is located;

[0145] S613. Determine preliminary fault type and preliminary fault severity through power range;

[0146] S614, dividing the target line based on the preliminary fault type and the preliminary fault severity to obtain multiple sub-lines;

[0147] S615: Use a preset fault location technology for each sub-line to determine the faulty sub-line and the fault location in the faulty sub-line.

[0148] Based on the fault current data and the fault voltage data, the fault location is determined. Specifically, the composite power of the fault line is calculated through the fault current data and the fault voltage data. In this embodiment, the composite power is the apparent power. The apparent power is used to describe the total power in the AC circuit, including active power and reactive power. The calculation formula of the apparent power is as follows:

[0149] S=P+jQ

[0150] Among them, S represents apparent power, P represents active power, Q represents reactive power, and j represents imaginary unit;

[0151] The real part of the composite power is the active power, and the imaginary part is the reactive power. By calculating the composite power of the fault line and analyzing the real and imaginary parts of the composite power, the preliminary fault type can be determined. The preliminary fault type can be a short circuit fault, a line break fault, and a ground fault. For example, if the reactive power is large, it may indicate the presence of a capacitive or inductive fault, such as an arc discharge in a ground fault. The power range in which the composite power is located is determined to determine the severity of the preliminary fault. The size of the composite power can reflect the severity of the fault. When there is a large composite power, it may mean that there is a large energy release or loss at the fault point, which requires more urgent processing. In other words, the composite power is compared with the preset power range. Different power ranges correspond to different severity levels. For example, when the preset power range can be set to a minor fault, a general fault, and a severe fault according to the actual situation, it is determined in which power range the composite power is, thereby determining the corresponding severity.

[0152] When the fault type and fault severity are preliminarily determined, the fault line is divided according to the preliminarily determined fault type and fault severity, that is, the fault line is divided based on the power range. In this embodiment, the power range is the power range where the composite power is located. When there are multiple fault types, the fault line is divided according to the fault type, such as short circuit fault, line break fault and ground fault. When the fault type is one, the fault line is divided according to the fault severity, such as minor fault, general fault and severe fault, so as to determine multiple sub-lines.

[0153] After determining multiple sub-circuits, the fault location is determined within the sub-circuit based on the preset fault location technology. In this embodiment, the fault location is the longitude and latitude coordinates of the fault within the sub-circuit. The preset fault location technology refers to a set of automatic and efficient fault point detection and location systems based on fault indicator technology, GSM communication technology and GIS technology. It is mainly used for the detection and location of various fault points in the power distribution system. Fault indicator technology refers to a device installed on the power line to indicate the fault current. It can detect and determine the circuit fault by detecting the characteristics of the fault current. GSM communication technology is a widely used second-generation digital cellular mobile communication standard. GIS technology is a computer-based tool for analyzing and processing spatial information. The longitude and latitude coordinates of the fault location in the sub-circuit can be accurately determined by the preset fault location technology, thereby determining the fault location within the sub-circuit.

[0154] By calculating the composite power of the fault line through the fault current data and the fault voltage data, the preliminary fault type and the preliminary fault severity can be determined, which helps to accurately determine the fault type and severity and take corresponding treatment measures. Based on the preliminary fault type and the preliminary fault severity, the fault line is divided to obtain multiple sub-lines, and the fault location is determined within the sub-line based on the preset fault location technology. According to the fault type and severity, a targeted fault handling plan can be formulated, which helps to improve the efficiency and quality of fault handling, timely discover and handle faults, prevent the fault from expanding, and avoid causing greater damage to the power system.

[0155] In one implementation manner of this embodiment, before obtaining the fault current data of the target line in the distribution network at the time of the fault, the method further includes:

[0156] S710, obtaining a terminal node and a branch node in a distribution line of a target phase, wherein the branch node is located at a connection point between a branch line of the distribution line and a main line of the distribution line, and the terminal node is located at a connection point between a branch line of the distribution line and a load device;

[0157] S720, the terminal node and the branch node constitute a section of the distribution line, the section of the distribution line includes a main line section and a branch line section, the line between the terminal node and the branch node is the branch line section, and the line between the branch node and the adjacent branch node is the main line section;

[0158] S730: Determine the impact degree of each section, and determine at least one target route according to the impact degree.

[0159] According to the fault current phase angle difference, the fault type is determined, and the target quadrant of the fault type in the four quadrants of the distribution network is determined, including:

[0160] S740, determining a preset angle range where the phase angle difference is located, and determining a user fault type corresponding to the target line through the preset angle range;

[0161] S750. Determine a target quadrant corresponding to the user type in the four quadrants of the distribution network according to the user fault type.

[0162] Based on the phase angle difference at the moment of the fault, the target quadrant where the target user is located in the four quadrants of the distribution network is determined. Specifically, first, the distribution line in the fault quadrant is phase-converted to obtain the distribution line of the target phase. The target phase includes the first modal phase and the second modal phase. In this embodiment, the distribution line in the fault quadrant is phase-converted by Clarke transformation, and the distribution line in the fault quadrant is converted from a three-phase stationary coordinate system to a two-phase stationary coordinate system; Clarke transformation is a coordinate transformation method commonly used in motor control and power systems. Its core idea is to convert the current or voltage in the three-phase stationary coordinate system into the current or voltage in the two-phase stationary coordinate system for analysis and control. That is to say, the distribution line in the fault quadrant is converted from the three-phase stationary coordinate system to the two-phase stationary coordinate system by Clarke transformation. In this embodiment, the three-phase stationary coordinate system is the abc coordinate system, and the two-phase stationary coordinate system is the coordinate system under the first modal phase and the coordinate system under the second modal phase, so as to obtain the target phase. In this embodiment, the target phase includes the first modal phase and the second modal phase, which are the phases obtained by Clarke transformation.

[0163] Figure 3 A schematic diagram of the structure of a main line section and a branch line section of a distribution network according to an embodiment of the present application is schematically shown. As shown in the figure, the main line of the distribution line includes a terminal node and a branch node. The line between the terminal node and the branch node is a branch line section, and the line between a branch node and an adjacent branch node is a main line section;

[0164] After obtaining the distribution line of the target phase, the terminal node and branch node in the distribution line of the target phase are obtained. In this embodiment, the branch node is located at the connection point between the branch line of the distribution line and the main line of the distribution line, and the terminal node is located at the connection point between the branch line of the distribution line and the load device. The branch node refers to the location where the current or signal is divided or merged in the distribution line. In the distribution network, the branch node is usually located at the connection point between the trunk line and the branch line, and plays the role of distributing or collecting current. The terminal node refers to the final receiving point or sending point of the current or signal in the distribution line. In the distribution system, the terminal node generally refers to the node directly connected to the power supply or load. As the end of the distribution line, the terminal node is directly connected to the load or user equipment. They are the starting point of electric energy use and the key nodes in the distribution line.

[0165] After obtaining the terminal nodes and branch nodes in the distribution line of the target phase, the terminal nodes and branch nodes constitute the section of the distribution line. In this embodiment, the section of the distribution line includes the main line section and the branch line section, wherein the line between the terminal node and the branch node is the branch line section, and the line between the branch node and the adjacent branch node is the main line section. The main line section refers to the line section connecting adjacent branch nodes, which is usually the backbone part of the distribution network and is responsible for transmitting electric energy from the power supply end to each branch node. The branch line section refers to the line section from the branch node to the terminal node, which is responsible for distributing electric energy from the main line section to a specific load point.

[0166] After determining the main line sections and branch line sections within the distribution line, determine the degree of influence of each section. In this embodiment, determining the degree of influence of each section refers to the influence of the faulty line on the fluctuation of electrical parameters of other lines, and determine the target line based on the degree of influence. That is to say, by judging the changes in electrical parameters in the distribution line, the degree of influence of each section is determined, and based on the degree of influence of each section, the target line is determined. In this embodiment, the target line is a section with a degree of influence greater than a preset threshold, and the section greater than the preset threshold is used as the target section.

[0167] According to the fault current phase angle difference, the fault type is determined, and the target quadrant of the fault type in the four quadrants of the distribution network is determined. That is to say, the fault type is obtained by comparing the fault current phase angle difference with the known fault type characteristics. For example, in the case of a symmetrical fault, the phase angle difference of the three-phase voltage and current is 120°, and the phase angle of the positive sequence component is consistent, and the phase angle of the negative sequence component is 0°. In the case of an asymmetrical fault, the phase angle difference of the three-phase voltage and current is not 120°, and the phase angles of the positive sequence component and the negative sequence component are different. Common asymmetrical fault types include single-phase grounding faults, two-phase short circuit faults, etc. Asymmetrical faults refer to faults in which the three-phase voltage and current are asymmetrical in amplitude or phase. This is because an asymmetrical fault will cause the magnitude and phase of the three-phase current to no longer be equal or differ by a fixed angle, so the phase angle difference also presents the characteristics of asymmetrical distribution. If the phase angle difference meets the characteristics of a symmetrical fault, for example, the three-phase phase angle difference is 120°, and the phase angles of the positive sequence components are consistent and the phase angle of the negative sequence component is 0°, then it is judged as a symmetrical fault. If the phase angle difference does not meet the characteristics of a symmetrical fault, further analysis is performed to determine whether it meets the characteristics of an asymmetrical fault. After determining the fault type, determine the fault type and determine the target quadrant of the fault type in the four quadrants of the distribution network. Specifically, determine the preset angle range of the phase angle difference, and determine the user type corresponding to the target line through the preset angle range. After obtaining the user type, determine the target quadrant corresponding to the user type in the four quadrants of the distribution network. For example, when the phase difference is between 0° and 90° and the power factor is greater than 0, the target user is in the first quadrant; when the phase difference is between -90° and 0° and the power factor is less than 0, it means that active power is emitted but reactive power is absorbed, and the target user is in the second quadrant; when the phase difference is between -90° and -180° and the power factor is less than 0, it means that active and reactive power are emitted, and the target user is in the third quadrant; when the phase difference is between 0° and 90° and the power factor is greater than 0, but the current direction is opposite to the voltage direction, the target user is in the fourth quadrant.

[0168] Another implementation method in this embodiment is to determine the target line and then determine the fault type through the following steps. Specifically, this step simplifies the analysis of complex three-phase asymmetric circuits by decomposing the asymmetric components in the three-phase circuit, such as current or electricity, into three groups of symmetrical components, namely positive sequence, negative sequence and zero sequence components. In the first modal phase, the first phase angle difference value at both ends of each target line is determined respectively. According to the first phase angle difference value, it is determined whether it is a preset first fault type. If it is the first fault type, the target fault type is determined. Specifically, in this embodiment, the first phase angle difference value refers to the phase angle difference value at both ends of the target line in the first modal phase. First, the current value in the first modal phase at both ends of the target line is obtained, and the first phase angle difference value is derived using the Clarke transformation formula and the current value in the first modal phase. The Clarke transformation formula is as follows:

[0169]

[0170] in, Represents the current value in the first mode phase, I a ,I b and I c Indicates the three-phase current phasor value, represents the first phase angle difference value within the first mode phase;

[0171] Therefore, the formula for the phase angle difference within the first mode phase can be derived using the following transformation formula, as shown below:

[0172]

[0173] Represents the first phase angle difference value within the first mode phase, θ a ,θ b and θ c Indicates the phase angles corresponding to the three phases respectively;

[0174] When a phase in the three-phase circuit fails, the first phase angle difference value in the first modal phase is not 0. When phases b and c fail, the first phase angle difference value in the first modal phase is also not 0. When the fault type is a short circuit between phases b and c, the first phase angle difference value in the first modal phase is 0.

[0175] Therefore, by analyzing the first phase angle difference value, it is determined whether the first phase angle difference value is 0, and then the first fault type is determined to be a bc phase short circuit or a phase a fault, or a phase b and c fault. For example, when the first phase angle difference value is 0, it can be determined that the first fault type is a bc phase short circuit; when the first phase angle difference value is not 0, it is determined that the first fault type is an a phase fault or a phase b and c fault. When the first phase angle difference value is not 0, it is necessary to analyze the phase angle difference in the second modal phase to further determine the fault type.

[0176] Subsequently, within the second modal phase, the second phase angle difference value at both ends of each target line is determined respectively to obtain the second target fault line. In this embodiment, the second phase angle difference value refers to the phase angle difference value at both ends of the target line within the second modal phase. First, the current values ​​within the second modal phase at both ends of the target line are obtained, and the second phase angle difference value is derived using the transformation formula and the current value within the second modal phase. The transformation formula is as follows:

[0177]

[0178] Among them, I β Represents the current value in the first mode phase, I b and Ic Indicates the b-phase current and c-phase current in the three-phase current, θ β Represents the second phase angle difference value within the second mode phase;

[0179] Therefore, the transformation formula can be used to deduce the formula for the phase angle difference within the second mode phase, as shown below:

[0180]

[0181] θ β Represents the second phase angle difference value within the second mode phase, θ b and θ c Indicates the phase angle between phase b and phase c in the three-phase system, I b and I c Indicates the b-phase current and c-phase current in the three-phase current;

[0182] The second target fault line is determined by the second phase angle difference value. Specifically, when a fault occurs in phase b or phase c, the second phase angle difference value in the second modal phase is not 0. When a fault occurs in phase a, the second phase angle difference value is 0.

[0183] Therefore, by analyzing the second phase angle difference value, it is determined whether the second phase angle difference value is 0, and then the second fault type is determined to be a short circuit between phases b and c or a phase fault, or a phase b and a phase c fault. For example, when the second phase angle difference value is not 0, it can be determined that the fault type is a fault in phase b or phase c, and when the second phase angle difference value is 0, it can be determined that the fault type is a phase fault.

[0184] By determining the target quadrant of the target user in the four quadrants of the distribution network through the phase angle difference at the time of the fault, the fault point can be located more quickly, the troubleshooting time can be shortened, and it is helpful to timely discover and deal with potential unstable factors in the power system and improve the stability of the power system.

[0185] In one implementation of this embodiment, determining the influence degree of each section and determining at least one target route according to the influence degree includes:

[0186] S801, obtaining the transmission power of each section at the time of the fault;

[0187] S802, comparing each transmission power with a preset reference power, marking a section that exceeds the preset reference power, and obtaining an over-reference power section;

[0188] S803, comparing the transmission power of each section at the time of the fault with a preset reference power, marking the section that does not exceed the preset reference power, and obtaining the section that does not exceed the reference power;

[0189] S804, determining the difference between each super-reference power section and a preset reference power to obtain a first power number set;

[0190] S805, determining the difference between each power section that does not exceed the reference power and exceeds the preset reference power, and obtaining a second power number set;

[0191] S806, forming a matrix with the first power number set and the second power number set, wherein a row vector in the matrix represents each segment, and a column vector in the matrix is ​​formed by the first power number set and the second power number set;

[0192] S807. Determine the impact level of each section based on a preset risk assessment matrix;

[0193] S808, multiplying the influence degree of each section by the power value of each corresponding section in the matrix to obtain an influence degree matrix;

[0194] S809: Mark the sections in the influence degree matrix that exceed the preset threshold, and use the sections that exceed the preset threshold as target lines.

[0195] Determine the impact of each section, and determine the target line based on the impact. Specifically, first, obtain the transmission power of each section at the time of the fault. The transmission power of each section can be directly measured by a power measurement device, such as a power meter. The transmission power represents the electric energy transmitted through a specific circuit or device in a unit time. In the power system, the size of the transmission power is directly related to the distribution, utilization and efficiency of electric energy.

[0196] After determining the transmission power, each transmission power is compared with a preset reference power, and the segment exceeding the preset reference power is marked to obtain an over-reference power segment. The preset reference power can be determined based on the capacity, load demand, and safety of the actual power system. That is to say, the transmission power data of each segment is compared with the preset reference power, and the segment exceeding the reference power is identified. The segment exceeding the reference power may have problems such as overload, voltage fluctuation, or power oscillation, and the segment exceeding the reference power is marked for subsequent analysis and processing, thereby determining the over-reference power segment. In this embodiment, the over-reference power segment is a segment exceeding the preset reference power.

[0197] Similarly, the transmission power of each section at the time of the fault is compared with the preset reference power, and the section that does not exceed the preset reference power is marked to obtain the section that does not exceed the reference power. The preset reference power can be determined according to the capacity, load demand, and safety of the actual power system. In this embodiment, the section that does not exceed the reference power is the section that does not exceed the preset reference power. In other words, the transmission power data of each section is compared with the preset reference power, and the section that does not exceed the reference power is identified, and the section that does not exceed the reference power is marked for subsequent analysis and processing, thereby determining the section that does not exceed the reference power.

[0198] After determining the power segment that does not exceed the benchmark power and determining the power segment that exceeds the benchmark power, determine the difference between the power segment that exceeds the benchmark power and the preset benchmark power to obtain a first power number set. In this embodiment, the first power number set is a set of power difference values ​​obtained by subtracting the benchmark power from the transmission power, that is, the power difference is obtained by subtracting the transmission power from the benchmark power. Since the power value of the power segment that does not exceed the benchmark power must be less than the preset benchmark power, the power value in the first power number set is 0 or a negative value.

[0199] After obtaining the first power number set, the difference between the power segment that does not exceed the preset reference power is determined to obtain the second power number set. In this embodiment, the second power number set is a set of power difference values ​​obtained by subtracting the reference power from the transmission power, that is, the power difference is obtained by subtracting the reference power from the transmission power. Since the power value of the power segment that exceeds the reference power must be greater than the preset reference power, the power value in the first power number set is a positive value.

[0200] After obtaining the first power number set and the second power number set, the first power number set and the second power number set are formed into a matrix, wherein the row vector in the matrix represents each segment, and the column vector in the matrix is ​​composed of the first power number set and the second power number set, that is, each segment is taken as a row vector of the matrix, and the difference between the segment that does not exceed the benchmark power and exceeds the preset benchmark power and the difference between the segment that exceeds the benchmark power and exceeds the preset benchmark power are respectively taken as column vectors of the matrix, thereby obtaining a matrix.

[0201] Based on the preset risk assessment matrix, the impact degree of each section is determined. The preset risk assessment matrix usually consists of a two-dimensional table. The horizontal axis represents the possibility of risk occurrence, and the vertical axis represents the impact degree of the risk. The cells in the matrix can be graded and color-coded according to the possibility and impact degree of the risk to reflect the level of risk. Common color codes include red high risk, yellow medium risk and green low risk. That is to say, through the preset risk assessment matrix, the degree of impact of each section due to the failure of the distribution network is determined, and the target line is determined according to the impact degree of each section.

[0202] After obtaining the degree of influence of each section, the degree of influence of each section is multiplied by the power value of each section corresponding to the matrix to obtain the degree of influence matrix. In this embodiment, the degree of influence matrix refers to the matrix of the degree of influence of the distribution line fault on other section lines. Each row of this matrix represents a line section, and the value in the matrix represents the product of the degree of influence of the section.

[0203] The sections exceeding the preset threshold in the influence degree matrix are marked and taken as target routes. The preset threshold can be determined according to the actual situation. That is, the sections exceeding the threshold are marked to obtain the target routes.

[0204] By determining the degree of impact of each section and ultimately determining the target line, we can accurately identify risk sections, quantify risk impacts, improve the operational efficiency of the power system, and ensure the safe, stable and efficient operation of the power system.

[0205] An embodiment of the present application also provides a machine-readable storage medium, on which instructions are stored, and the instructions are used to enable a machine to execute the above-mentioned four-quadrant adaptive intelligent current protection method for the distribution network.

[0206] The embodiment of the present application also provides a four-quadrant adaptive intelligent current protection system for a distribution network, comprising:

[0207] a memory configured to store instructions; and

[0208] The processor is configured to call instructions from the memory and implement the above-mentioned four-quadrant adaptive intelligent current protection method for the distribution network when executing the instructions.

[0209] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0210] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0211] These computer program instructions may also be stored in a computer readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0212] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0213] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0214] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0215] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tape disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0216] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0217] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A four-quadrant adaptive intelligent current protection method for a distribution network, characterized in that: include: Obtaining fault current data and fault voltage data of a target line in a distribution network at the time of a fault; Determining the phase angle difference of the target line according to the fault current data and the fault voltage data; Determine the fault type according to the fault current phase angle difference, and determine the target quadrant of the fault type in the four quadrants of the distribution network, the fault types including resistive and inductive load user faults, non-clean energy power generation user faults, clean energy power generation users, resistive and capacitive load user faults, and line faults after the power flow direction changes after the operation mode changes; Determine whether the fault current data is greater than the current setting corresponding to the target quadrant, and if the fault current data is greater than the current setting, perform overcurrent protection on the target user fault, and perform overcurrent protection on the line fault with the same point fault due to different fault currents under different operating modes due to the change of the flow direction after the operating mode changes.

2. The method according to claim 1, characterized in that In the four quadrants of the distribution network, the resistive-inductive load users are located in the first quadrant of the four quadrants, the non-clean energy power generation users are located in the second quadrant of the four quadrants, the clean energy power generation users are located in the third quadrant of the four quadrants, and the resistive-capacitive load users are located in the fourth quadrant of the four quadrants. The resistive-inductive load users are used to input active power and reactive power into the distribution network, the non-clean energy power generation users are used to output active power and reactive power to the distribution network, the clean energy power generation users are used to output active power and reactive power to the distribution network, and the resistive-capacitive load users are used to input active power and reactive power to the distribution network; Before acquiring the fault current data and the fault voltage data of the target line in the distribution network at the time of the fault, the method includes: Acquire current data and voltage data of the distribution network in real time, and determine whether the distribution network has a fault according to the current data and the voltage data; In the case where there is a fault in the distribution network, the step of acquiring the fault current data and the fault voltage data of the target line in the distribution network at the time of the fault is performed.

3. The method according to claim 2, characterized in that The determining the phase angle difference of the target line according to the fault current data and the fault voltage data comprises: Obtaining an instantaneous power value of the distribution network at the moment of the fault through the fault current data and the fault voltage data, wherein the instantaneous power value includes reactive power and active power; Based on the reactive power and the active power, determining an input value and an output value of the reactive power, and an input value and an output value of the active power; Calculating the power factor of the target line at the fault moment through the input value and output value of the reactive power and the input value and output value of the active power; The phase angle difference of the target line is obtained by using a preset phase angle formula and calculating according to the power factor.

4. The method according to claim 3, characterized in that The determining whether the power distribution network has a fault according to the current data and the voltage data includes: Acquire historical sample current data and historical sample voltage data; Constructing a historical current spectrum diagram and a historical voltage spectrum diagram according to the historical sample current data and the historical sample voltage data; Constructing a real-time current spectrum diagram and a real-time voltage spectrum diagram according to the current data and the voltage data acquired in real time; Extracting a historical current feature vector of the historical current spectrum graph and a historical voltage feature vector of the historical voltage spectrum graph; Extracting a real-time current feature vector of the real-time current spectrum diagram and a real-time voltage feature vector of the real-time voltage spectrum diagram; Calculating a first similarity between the historical current feature vector and the real-time current feature vector; Calculating a second similarity between the historical voltage feature vector and the real-time voltage feature vector; If either the first similarity or the second similarity is smaller than a preset similarity threshold, it is determined that a fault exists in the power distribution network.

5. The method according to claim 4, characterized in that The real-time current feature vector includes a current amplitude and a current phase, the real-time voltage feature vector includes a voltage amplitude and a voltage phase, and the voltage feature vector includes a voltage amplitude and a voltage phase. After constructing a real-time current spectrum diagram and a real-time voltage spectrum diagram by using the current data and the voltage data acquired in real time, the method includes: Judging whether there is signal interference in the real-time current spectrum diagram according to the current amplitude and the current phase of the real-time current spectrum diagram; If the current amplitude in the real-time current spectrum diagram is greater than a preset reference amplitude and the offset value of the current phase is greater than a preset phase threshold, it is determined that there is signal interference in the real-time current spectrum diagram; Using a preset spectrum correction method to correct the real-time current spectrum diagram; Judging whether there is signal interference in the real-time voltage spectrum graph according to the voltage amplitude and the voltage phase of the real-time voltage spectrum graph; If the voltage amplitude in the real-time voltage spectrum diagram is greater than a preset reference amplitude and the offset value of the voltage phase is greater than a preset phase threshold, it is determined that there is signal interference in the real-time voltage spectrum diagram; The real-time voltage spectrum diagram is corrected using a preset spectrum correction step.

6. The method according to claim 1, characterized in that The method further comprises: Calculating the composite power of the fault line through the fault current data and the fault voltage data; Determine a power range within which the composite power lies; Determining a preliminary fault type and a preliminary fault severity through the power range; Based on the preliminary fault type and the preliminary fault severity, dividing the target line to obtain a plurality of sub-lines; A preset fault location technology is used for each of the sub-circuits to determine the faulty sub-circuits and the fault location in the faulty sub-circuits.

7. The method according to claim 6, characterized in that Before acquiring the fault current data of the target line in the distribution network at the time of the fault, the method further includes: Acquire a terminal node and a branch node in the distribution line of the target phase, wherein the branch node is located at a connection point between a branch line of the distribution line and a main line of the distribution line, and the terminal node is located at a connection point between a branch line of the distribution line and a load device; The terminal node and the branch node constitute a section of the distribution line, the section of the distribution line includes a main line section and a branch line section, the line between the terminal node and the branch node is the branch line section, and the line between the branch node and the adjacent branch node is the main line section; Determining the impact degree of each of the sections, and determining at least one target route according to the impact degree; Determining the fault type according to the fault current phase angle difference, and determining the target quadrant of the fault type in the four quadrants of the distribution network, includes: Determine a preset angle range where the phase angle difference is located, and determine a user fault type corresponding to the target line through the preset angle range; According to the user fault type, a target quadrant corresponding to the user type is determined in the four quadrants of the power distribution network.

8. The method according to claim 7, characterized in that The determining the influence degree of each of the sections and determining at least one target route according to the influence degree comprises: Obtaining the transmission power of each of the sections at the time of the fault; Comparing each of the transmission powers with a preset reference power, marking the section exceeding the preset reference power, and obtaining an over-reference power section; Comparing the transmission power of each section at the time of the fault with a preset reference power, marking the section that does not exceed the preset reference power, and obtaining a section that does not exceed the reference power; Determine the difference between each of the super-reference power sections and a preset reference power to obtain a first power value set; Determine the difference between each of the power sections that does not exceed the reference power and exceeds the preset reference power, and obtain a second power value set; The first power number set and the second power number set form a matrix, wherein a row vector in the matrix represents each of the segments, and a column vector in the matrix is ​​formed by the first power number set and the second power number set; Determining the impact level of each of the segments based on a preset risk assessment matrix; Multiplying the influence degree of each of the sections by the power value of each of the sections corresponding to the matrix to obtain an influence degree matrix; The sections exceeding the preset threshold in the influence degree matrix are marked, and the sections exceeding the preset threshold are used as target routes.

9. A machine-readable storage medium, characterized in that: The machine-readable storage medium stores instructions, which are used to enable the machine to execute the four-quadrant adaptive intelligent current protection method for the distribution network according to any one of claims 1 to 8.

10. A four-quadrant adaptive intelligent current protection system for a distribution network, characterized in that: include: a memory configured to store instructions; as well as A processor is configured to call the instruction from the memory and implement the four-quadrant adaptive intelligent current protection method for a power distribution network according to any one of claims 1 to 8 when executing the instruction.

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