A Line Pilot Protection Method Based on the Similarity of Current Differential Double Cumulants

Abstract

The present invention provides a line longitudinal protection method based on the similarity of current differential double cumulative amount, which can accurately locate faults and relates to data processing technology. The method includes dividing the line of the energy storage new energy station to obtain the new energy station side and the system side, obtaining the station side current and the system side current of the new energy station side and the system side; respectively calculating the instantaneous differential component of the station side current and the system side current, obtaining the station side differential component and the system side differential component, calculating the accumulation of the station side differential component and the system side differential component within a preset period, obtaining the station side cumulative amount and the system side cumulative amount and performing multiple differential accumulations, performing Pearson similarity calculation to obtain a reference value, and obtaining a first response action based on the reference value; if the first response action meets the preset requirements, then constructing a function based on the station side current and / or the system side current to obtain an action function, and comparing the action function with the preset function to obtain a line longitudinal protection result.

Description

Technical Field

[0001] The invention relates to data processing technology, and in particular to a line pilot protection method based on current differential double cumulative amount similarity. Background Art

[0002] As the installed capacity of renewable energy sources such as wind power and photovoltaics is growing rapidly, their contribution to energy supply is becoming increasingly significant. However, the output power of such renewable energy is significantly unstable and intermittent, which poses a considerable challenge to the stable operation of the power grid. In order to meet this challenge, energy storage technology is widely used to balance the output power of renewable energy. Therefore, new energy stations equipped with energy storage will become one of the mainstream modes of renewable energy development in future active distribution networks.

[0003] In the existing technology, traditional grid protection measures are often designed based on stable power supply characteristics, which makes it difficult to effectively respond to new changes brought about by new energy stations. In particular, when new energy stations are equipped with energy storage systems, the size and direction of their output power can be controlled, resulting in the possibility of changes in the direction of short-circuit current when the grid fails, and the traditional relay protection criteria may fail.

[0004] Therefore, how to accurately and reliably identify the fault location after a fault occurs in the distribution network connected to the energy storage power station based on the new characteristics of the new energy station after it is connected to the power grid has become an urgent problem that needs to be solved. Summary of the invention

[0005] The present invention provides a line longitudinal protection method based on the similarity of current differential double cumulative amounts, which can accurately and reliably identify the fault location after a fault occurs in a distribution network connected to an energy storage power station according to the new characteristics after the new energy station is connected to the power grid.

[0006] A first aspect of the present invention provides a line pilot protection method based on current differential double cumulative similarity, comprising:

[0007] The line of the energy storage new energy station is divided and processed to obtain the new energy station side and the system side, and the station side current and the system side current of the new energy station side and the system side are obtained respectively based on the current transformer;

[0008] The instantaneous difference components of the station-side current and the system-side current are calculated respectively to obtain the station-side difference component and the system-side difference component, and the accumulation of the station-side difference component and the system-side difference component within a preset period is calculated to obtain the station-side cumulative amount and the system-side cumulative amount;

[0009] Performing multiple differential accumulations based on the station-side cumulative amount and the system-side cumulative amount, and performing Pearson similarity calculation to obtain a reference value, and obtaining a first response action based on the reference value;

[0010] If the first response action meets the preset requirements, a function is constructed based on the station-side current and / or the system-side current to obtain an action function, and the action function is compared with the preset function to obtain a line longitudinal protection result.

[0011] Optionally, in a possible implementation manner of the first aspect, respectively calculating the instantaneous differential components of the station-side current and the system-side current to obtain the station-side differential component and the system-side differential component, and calculating the accumulation of the station-side differential component and the system-side differential component within a preset period to obtain the station-side cumulative amount and the system-side cumulative amount include:

[0012] Obtain the current sampling values ​​of the station-side current at adjacent time points and perform difference calculation to obtain the station-side difference component;

[0013] Obtaining current sampling values ​​of the system side current at adjacent time points and performing difference calculation to obtain a system side difference component;

[0014] The station-side differential quantities of all time points within a preset period are counted to obtain the station-side cumulative quantities;

[0015] The system side differential quantity at all time points within a preset period is counted to obtain the system side cumulative quantity.

[0016] Optionally, in a possible implementation manner of the first aspect, performing multiple differential accumulations based on the station-side cumulative amount and the system-side cumulative amount, performing Pearson similarity calculation to obtain a reference value, and obtaining a first response action based on the reference value includes:

[0017] Double cumulative values ​​are calculated for the station side cumulative amount and the system side cumulative amount respectively, and a station side set and a system side set are generated based on the time series based on the double cumulative amount on the station side and the double cumulative amount on the system side;

[0018] The station side set and the system side set respectively contain the station side double cumulative amount and the system side double cumulative amount sorted in time series, and the number of elements in the station side set and the system side set is the same as the number of samples in one power frequency cycle;

[0019] The station side set and the system side set are processed based on Pearson similarity calculation to obtain a reference value, and a first response action is obtained based on the reference value.

[0020] Optionally, in a possible implementation manner of the first aspect, the processing the station side set and the system side set based on the Pearson similarity calculation to obtain a reference value, and obtaining a first response action based on the reference value includes:

[0021] The station side set and the system side set are respectively used as two groups of input vectors to perform Pearson similarity calculation to obtain the Pearson similarity coefficient. The value range of the Pearson correlation coefficient is [-1,1];

[0022] Obtaining a reference value based on the value of the Pearson similarity coefficient;

[0023] If the distance between the reference value and -1 is less than the first preset requirement, it is judged as an out-of-zone fault, and a first response action of not performing a protection action is obtained;

[0024] If the reference value is greater than 0 and the distance value is less than the first preset requirement, it is determined to be an in-zone fault, and a first response action of performing a protection action is obtained.

[0025] Optionally, in a possible implementation manner of the first aspect, if the first response action meets a preset requirement, constructing a function based on the station-side current and / or the system-side current to obtain an action function, and comparing the action function with a preset function to obtain a line longitudinal protection result, including:

[0026] If it is determined to be an out-of-zone fault, the first response action meets the preset requirements, then the first time of generating the first response action is obtained, the second time is determined by reverse calculation according to the first preset time period, and the first time period is obtained based on the first time and the second time;

[0027] Acquiring power information on the system side within a first time period to obtain a first action function, wherein the first action function includes first sub-functions of different phases;

[0028] The first action function is compared with a first preset function to obtain a first comparison result, and an action device is determined based on the comparison result to obtain a line longitudinal protection result.

[0029] Optionally, in a possible implementation manner of the first aspect, comparing the first action function with a first preset function to obtain a first comparison result, and determining an action device based on the comparison result to obtain a line longitudinal protection result includes:

[0030] The first sub-functions of different phases are segmented and processed according to a preset time interval to obtain a plurality of first function segments, and each first function segment is numbered according to the time sequence of the first function segments to obtain a multi-dimensional number, wherein the multi-dimensional number includes a first phase dimension number and a first function segment sequence number;

[0031] Calculating the phase difference of the first sub-functions with different phases to obtain a plurality of phase difference groups;

[0032] Based on the first phase dimension number and the first function segment sequence number, determining a preset function segment corresponding to each first function segment in the first preset function;

[0033] A first comparison result is obtained by fusion comparison of the first function segment, the preset function segment, and the phase difference of the phase difference group, and an action device is determined based on the first comparison result to obtain a line longitudinal protection result.

[0034] Optionally, in a possible implementation manner of the first aspect, obtaining a first comparison result based on fusing and comparing the first function segment, the preset function segment, and the phase difference of the phase difference group, and determining an action device based on the first comparison result to obtain a line longitudinal protection result includes:

[0035] Taking each first function segment and preset function segment with the same multi-dimensional label as a function group, calculating the first slope and the preset slope of the first function segment and the preset function segment in the function group, and obtaining a first difference between the first slope and the preset slope;

[0036] Calculating the extreme value difference between each first sub-function and a preset sub-function;

[0037] Based on the first difference, the phase difference of each phase difference group, and the extreme value difference of each phase difference group, a first similarity is obtained by fusion comparison, and the faulty device corresponding to the first similarity with the largest value is determined as the first comparison result. Based on the faulty device, the action device is determined to obtain the line longitudinal protection result.

[0038] Optionally, in a possible implementation manner of the first aspect, if the first response action meets a preset requirement, a first action function is obtained by constructing a function based on the station-side current and / or the system-side current, and the first action function is compared with a preset function to obtain a line longitudinal protection result, including:

[0039] If it is determined to be an in-zone fault, the first response action meets the preset requirements, then the third time for generating the first response action is obtained, and the fourth time is determined by reverse calculation according to the second preset time period, and the second time period is obtained based on the third time and the fourth time;

[0040] Acquiring the electric energy information at the station side in a second time period to obtain a second action function, wherein the second action function includes second sub-functions of different phases;

[0041] The second action function is compared with a second preset function to obtain a second comparison result, the second comparison result is verified to obtain a verified second comparison result, and the action device is determined based on the verified second comparison result to obtain a line longitudinal protection result.

[0042] Optionally, in a possible implementation manner of the first aspect, comparing the second action function with a second preset function to obtain a second comparison result, verifying the second comparison result to obtain a verified second comparison result, and determining an action device based on the verified second comparison result to obtain a line longitudinal protection result includes:

[0043] Segment the second sub-functions of different phases according to a preset time interval to obtain a plurality of second function segments, and label each second function segment according to the time sequence of the second function segments to obtain a multi-dimensional label, wherein the multi-dimensional label includes a second phase dimension number and a second function segment sequence number;

[0044] Calculating phase differences of second sub-functions with different phases to obtain multiple phase difference groups;

[0045] Based on the second phase dimension number and the second function segment sequence number, determining a preset function segment corresponding to each second function segment in the second preset function;

[0046] Based on the phase difference fusion comparison of the second function segment, the preset function segment, and the phase difference group, a second comparison result is obtained, a third function on the system side corresponding to the second action function is obtained, and the second action function is verified based on the third function to obtain a verified second comparison result.

[0047] Optionally, in a possible implementation manner of the first aspect, obtaining a second comparison result based on fusing and comparing the second function segment, the preset function segment, and the phase difference group, obtaining a third function on the system side corresponding to the second action function, and verifying the second action function based on the third function to obtain a verified second comparison result includes:

[0048] Calling the verification function corresponding to the second action function, if the verification function is empty, directly using the second action function as the second comparison result after verification processing;

[0049] If the verification function is not empty, the third function and the verification function are respectively decomposed to obtain a third function segment and a verification function segment, and a second comparison result after verification is obtained by fusion comparison of the third function segment, the verification function segment and the verification phase difference group.

[0050] Optionally, in a possible implementation manner of the first aspect, the third function and the verification function are respectively decomposed to obtain a third function segment and a verification function segment, and a second comparison result after verification is obtained based on a fusion comparison of the third function segment, the verification function segment, and the verification phase difference of the verification phase difference group, including:

[0051] Taking each third function segment and verification function segment with the same multi-dimensional label as a verification function group, calculating the third slope and verification slope of the third function segment and verification function segment, and obtaining the verification difference between the third slope and the verification slope;

[0052] Calculate the extreme value difference between each third sub-function and the verification sub-function;

[0053] The verification similarity is obtained based on the verification difference, the verification phase difference of each verification phase difference group, and the verification extreme value difference of each verification phase difference group. If the verification similarity is greater than the verification preset value, the verification result is judged to be passed, and a second comparison result of the verification result passing is obtained.

[0054] According to a second aspect of the present invention, a storage medium is provided, in which a computer program is stored. When the computer program is executed by a processor, it is used to implement the method of the first aspect of the present invention and various possible designs of the first aspect.

[0055] The beneficial effects of the present invention are as follows:

[0056] 1. The present invention can effectively distinguish internal and external faults according to the new characteristics of the new energy station after it is connected to the power grid. It is suitable for the scenario where a high proportion of new energy stations with energy storage are connected to the distribution network, so that the fault location can be accurately and reliably identified after a fault occurs in the distribution network connected to the energy storage power station. Among them, the present invention can more effectively capture the current change characteristics during power grid faults by calculating the current difference between the new energy station side and the system side, and accumulating and accumulating the difference multiple times. Secondly, through the Pearson similarity calculation, the fault power information can be accurately judged, so as to distinguish the corresponding internal and external faults in the region later, thereby improving the accuracy and reliability of line protection.

[0057] 2. The present invention can accurately locate faults, improve the reliability of line protection, and is suitable for new energy station environments. The present invention can quickly and accurately identify line fault areas through similarity calculation of cumulative quantities, and can amplify current waveform differences through double cumulative quantities to determine protection performance under complex fault conditions, fully considering the characteristics of new energy stations and improving the applicability of protection in new energy environments.

[0058] 3. The present invention can effectively solve the protection problem after the new energy station is connected to the power grid through the fine analysis of the current waveform, and provide solid technical support for improving the stability and security of the power grid. Among them, the present invention can compare the corresponding action function with the preset function in multiple dimensions through the determined out-of-area faults and in-area faults, so as to determine the corresponding comparison results, and because when the equipment in the station fails, it may affect the system power outside the station, so the corresponding second comparison result can be further verified by the verification function, which is convenient for improving the accuracy of fault identification, so as to timely perform line protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 A flow chart of a line pilot protection method based on current differential double cumulative similarity provided by the present invention;

[0060] Figure 2 A schematic diagram of the topological structure of a power distribution network connected to a photovoltaic power station provided by the present invention. DETAILED DESCRIPTION

[0061] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0062] The terms "first", "second", "third", "fourth", etc. (if any) in the description and claims of the present invention and the above drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in sequences other than those illustrated or described herein.

[0063] It should be understood that in various embodiments of the present invention, the size of the sequence number of each process does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0064] It should be understood that in the present invention, "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus comprising a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products or apparatuses.

[0065] It should be understood that in the present invention, "plurality" refers to two or more than two. "And / or" is merely a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the objects associated before and after are in an "or" relationship. "Contains A, B and C", "Contains A, B, C" means that A, B, and C are all included, "Contains A, B or C" means that one of A, B, and C is included, and "Contains A, B and / or C" means that any one, any two, or any three of A, B, and C are included.

[0066] It should be understood that in the present invention, "B corresponding to A", "B corresponding to A", "A corresponds to B" or "B corresponds to A" means that B is associated with A and B can be determined based on A. Determining B based on A does not mean determining B based only on A, but B can also be determined based on A and / or other information. A and B match when the similarity between A and B is greater than or equal to a preset threshold.

[0067] Depending on the context, "if" as used herein may be interpreted as "when" or "when" or "in response to determining" or "in response to detecting."

[0068] The technical solution of the present invention is described in detail with specific embodiments below. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0069] like Figure 1 As shown, the present invention provides a line pilot protection method based on the similarity of current differential double cumulative amounts. The specific implementation of the line pilot protection method based on the similarity of current differential double cumulative amounts includes:

[0070] S1, divide the lines of the energy storage new energy station to obtain the new energy station side and the system side, and obtain the station side current and system side current of the new energy station side and the system side respectively based on the current transformer.

[0071] It should be noted that when a fault occurs in the dedicated line connected to the new energy station with energy storage, the fundamental frequency short-circuit current fed back by the new energy station with energy storage will no longer always flow from the power supply to the fault point, especially when the new energy station with energy storage absorbs electric energy as a whole, its fundamental frequency short-circuit current will flow from the fault point to the power supply side, and will no longer always flow from the power supply point to the fault point. The characteristics of the fault current flow direction make the traditional relay protection judgment criteria face the risk of failure. Therefore, the protection method of the corresponding line can be determined by the similarity relationship between the double cumulative amounts of the instantaneous current difference between the station side and the system side of the dedicated line connected to the new energy station with energy storage, so as to correctly identify the faults in the distribution network connected to the photovoltaic power station with energy storage.

[0072] It can be understood that the new energy station side is the side of the power grid line that contains a new energy station, for example, the line side of the line contains photovoltaic power sources and storage power sources; the system side is the side of the power grid line that uses load electricity, for example, the line side of the line contains power-consuming equipment; the station side current is the current corresponding to the new energy station side, and the system side current is the current corresponding to the system side of the line.

[0073] It is worth mentioning that the present invention is applied to the power grid environment of energy storage and renewable energy stations. When there is no energy storage and renewable energy station in the power grid line, the method will no longer be applicable.

[0074] Through the above implementation, the present invention can determine the corresponding station-side current and system-side current, so as to subsequently calculate the corresponding current difference, thereby accurately identifying the fault and performing line protection.

[0075] S2, respectively calculate the instantaneous differential components of the station side current and the system side current to obtain the station side differential component and the system side differential component, calculate the accumulation of the station side differential component and the system side differential component within a preset period, and obtain the station side cumulative amount and the system side cumulative amount.

[0076] It can be understood that the instantaneous differential component is the instantaneous current difference, the station side differential component is the instantaneous differential value of the current corresponding to the new energy station side, the system side differential component is the instantaneous differential value of the current corresponding to the system side, the preset period is a pre-set time period, which is used to count the current difference within the corresponding time period in order to protect the line, the station side cumulative amount is the cumulative value of the differential component corresponding to the new energy station side, and the system side cumulative amount is the cumulative value of the system side differential component within the preset period.

[0077] Through the above implementation, the present invention can obtain the station-side cumulative amount and the system-side cumulative amount in the corresponding line, so as to perform subsequent current similarity comparison and thus perform line protection.

[0078] In some embodiments, the specific implementation of step S2 (the instantaneous differential components of the station-side current and the system-side current are calculated respectively to obtain the station-side differential component and the system-side differential component, and the accumulation of the station-side differential component and the system-side differential component within a preset period is calculated to obtain the station-side cumulative amount and the system-side cumulative amount) includes:

[0079] S21, obtaining the current sampling values ​​of the station-side current at adjacent time points and performing difference calculation to obtain the station-side difference component.

[0080] It can be understood that the current sampling values ​​of the station-side current collected at adjacent time points are subjected to difference calculation, so that the corresponding station-side difference component can be calculated.

[0081] For example, the calculation method is ,in, is the jth sampling value of the current, It is the difference component of the j-th current sampling value corresponding to the new energy station side.

[0082] S22, obtaining current sampling values ​​of the system side current at adjacent time points and performing difference calculation to obtain a system side difference component.

[0083] It can be understood that by performing difference calculation on the current sampling values ​​of the system side current collected at adjacent time points, the corresponding system side differential component can be calculated.

[0084] For example, the calculation method is ,in, is the jth sampling value of the system side current, is the difference value corresponding to the jth current sampling value on the system side.

[0085] S23, calculating the station-side differential quantities at all time points within a preset period to obtain the station-side cumulative quantity.

[0086] It is understandable that after obtaining the differential value on the station side, the values ​​of all time points within the preset period can be further counted, so that the cumulative amount on the station side can be obtained, so that the Pearson similarity calculation can be performed through multiple differential accumulations later.

[0087] For example, to calculate the cumulative amount of the current difference within a preset period, the expression can be: ,in, It represents the current differential accumulation calculated at the new energy station side in the mth power frequency cycle, and N represents the number of sampling points in a preset cycle.

[0088] S24, counting the system side differential quantities at all time points within a preset period to obtain the system side cumulative quantity.

[0089] It can be understood that the system side differential components at all time points within the preset period are accumulated to obtain the system side cumulative amount, which is convenient for Pearson similarity calculation, thereby determining the corresponding line fault, so as to quickly and accurately perform line protection.

[0090] For example, to calculate the cumulative amount of the current difference within a preset period, the expression can be: ,in, It indicates the current differential accumulation calculated by the system side in the mth power frequency cycle, and N indicates the number of sampling points in a preset cycle.

[0091] S3, performing multiple differential accumulations based on the station-side cumulative amount and the system-side cumulative amount, and performing Pearson similarity calculation to obtain a reference value, and obtaining a first response action based on the reference value.

[0092] It should be noted that, taking the photovoltaic power station as an example, the normal operation or the occurrence of internal and external faults on the dedicated line is the change characteristic of the double accumulation of the current difference on both sides of the line, such as Figure 2 FIG. 1 is a schematic diagram of the topological structure of the power distribution network connected to the photovoltaic power station according to the embodiment of the present invention. Here, it is stipulated that the positive direction of the current on the line is the busbar flowing to the line. Figure 2 The positive direction of the current on the renewable energy station side of the middle line is from the renewable energy station side to the system side, and the positive direction of the current on the system side is from the system side to the renewable energy station side.

[0093] It is understandable that in normal operation, ignoring the influence of the line-to-ground capacitance current, the current flowing through both sides of the line should be the same. However, because the positive directions of the currents on both sides are exactly opposite, the instantaneous current waveforms on both sides show completely opposite trends. At this time, the current difference components on both sides satisfy the following relationship:

[0094] ,

[0095] in, It represents the difference of the jth current sampling value at the new energy station side. Represents the difference of the jth current sampling value on the system side, Indicates separation.

[0096] In view of this, after double accumulation, the current difference on both sides should satisfy the following relationship:

[0097] ,

[0098] in, is the calculation result of the kth current differential accumulation corresponding to the new energy station side, is the calculation result of the kth current differential accumulation on the system side.

[0099] Therefore, during normal operation, the values ​​of the double cumulative amounts of the current difference on both sides of the line are basically the same, and the change trends are completely opposite. Similarly, for out-of-zone faults, the same current flows through both sides of the line, and the amplitudes of the double cumulative amounts of the current difference are basically the same and the change trends are opposite. In the above cases, the similarity of the double cumulative amounts of the current difference on both sides shows a strong negative correlation.

[0100] However, if an in-region fault occurs on the line, when the photovoltaic power station provides active power to the grid (subject to the fault ride-through requirements for the access of new energy to the grid, once the grid fails, the reactive power output by the photovoltaic power station is always capacitive), the phase difference between the short-circuit current and its voltage on the new energy station side and the system side of the line are both acute angles, that is, the current flows from the line side to the fault point, and the change trend of its current differential double accumulation also changes accordingly. In this scenario, the similarity becomes positively correlated. When the photovoltaic power station absorbs power from the grid, the short-circuit current on the new energy station side of the line flows from the fault point to the power supply, and the short-circuit current on the system side flows from the power supply to the fault point. The flow direction of the current on both sides is similar to that of normal operating conditions or out-of-region faults, but the change trend of the current waveforms on both sides is not the same. The current differential double accumulation used in the present invention can amplify the degree of difference in the current waveforms on both sides, so that the current waveforms with differences show a strong positive similarity.

[0101] Therefore, the present invention uses the current differential double accumulation on both sides of the line as the input of the similarity algorithm, performs Pearson similarity calculation, and uses the similarity coefficients on both sides as a criterion to realize fault identification.

[0102] In some embodiments, the specific implementation of step S3 (the step of performing multiple differential accumulations based on the station-side cumulative amount and the system-side cumulative amount, performing Pearson similarity calculation to obtain a reference value, and obtaining a first response action based on the reference value) includes:

[0103] S31, performing double cumulative value calculations on the station side cumulative amount and the system side cumulative amount respectively, and generating a station side set and a system side set based on the time series based on the double cumulative amount on the station side and the double cumulative amount on the system side.

[0104] It should be noted that in order to perform Pearson similarity calculation on the current in the line, it is necessary to perform double cumulative value calculation on the station side cumulative amount and the system side cumulative amount respectively, so as to determine the double cumulative amounts corresponding to different times, thereby generating a station side set and a system side set, which is convenient for subsequent fault judgment and thus line protection.

[0105] It can be understood that the calculation expression of the double accumulation of the current difference components on both sides can be:

[0106] ,

[0107] In the formula, represents the calculation result of the kth current differential double accumulant, Indicates phase difference, subscript i=s,p, where s and p represent the system side and the new energy station side respectively.

[0108] It is not difficult to understand that the double cumulative amount on the station side is the double cumulative amount of the station side cumulative amount corresponding to the new energy station side, the double cumulative amount on the system side is the double cumulative amount of the system side cumulative amount corresponding to the system side, the station side set is the set of double cumulative amounts corresponding to the new energy station side arranged in chronological order, and the system side set is the set of double cumulative amounts corresponding to the system side arranged in chronological order.

[0109] S32, the station side set and the system side set respectively contain the station side double cumulative quantities and the system side double cumulative quantities sorted in time series, and the number of elements in the station side set and the system side set is the same as the number of samples in one power frequency cycle.

[0110] It can be understood that the set S and the set P respectively contain the differential double accumulants of the new energy station side and the system side currents sorted in time series, and the number of elements thereof is the same as the number of samples in a preset period.

[0111] For example: ,

[0112] ,

[0113] S33, processing the station side set and the system side set based on Pearson similarity calculation to obtain a reference value, and obtaining a first response action based on the reference value.

[0114] It can be understood that by performing Pearson similarity calculation on the station side set and the system side set, the parameter value for judging the fault in the line can be obtained, so that the corresponding first response action can be obtained according to the reference value, so as to timely protect the normal operation of the line.

[0115] The first response action is an execution action of responding to the fault for protection, so as to complete the line protection.

[0116] In some embodiments, the specific implementation of step S33 (processing the station side set and the system side set based on the Pearson similarity calculation to obtain a reference value, and obtaining a first response action based on the reference value) includes:

[0117] S331, taking the station side set and the system side set as two groups of input vectors respectively to perform Pearson similarity calculation processing to obtain the Pearson similarity coefficient, and the value range of the Pearson correlation coefficient is [-1,1].

[0118] It should be noted that the value range of the Pearson correlation coefficient is [-1,1], and the positive or negative value of the correlation coefficient indicates the positive or negative correlation of the double accumulative quantities of the current difference on both sides.

[0119] It can be understood that, according to the current differential double cumulants on both sides of the line, the set S and the set P are respectively used as two groups of input vectors S and vectors P, so as to obtain the Pearson similarity coefficient for subsequent fault judgment.

[0120] S332: Obtain a reference value based on the value of the Pearson similarity coefficient.

[0121] It can be understood that the Pearson similarity calculation expression used for Pearson similarity calculation is as follows:

[0122] ,

[0123] Among them, r is the Pearson similarity coefficient of the double cumulant of the current difference on both sides, that is, the reference value, and are the kth elements of vector S and vector P, respectively, corresponding to the current differential double accumulation on the new energy station side and the system side and , and are the means of each element of vector S and vector P respectively.

[0124] It is not difficult to understand that the reference value is the Pearson similarity coefficient value obtained by performing Pearson similarity calculation. If and only if the trends of the double cumulative amounts of current differences on both sides are completely opposite, that is, when one set of variables increases, the other set of variables decreases at exactly the same proportion, the obtained similarity coefficient is -1, which represents a complete negative correlation. If and only if the trends of the double cumulative amounts of current differences on both sides are exactly the same, that is, when one set of variables increases, the other set of variables also increases at exactly the same proportion, the obtained similarity coefficient is 1. When there is no clear increase or decrease correlation between the two sets of variables, the numerators cancel each other out, and the obtained similarity coefficient is 0.

[0125] S333: If the distance between the reference value and -1 is less than the first preset requirement, it is judged as an out-of-zone fault, and a first response action of not performing a protection action is obtained.

[0126] It can be understood that when the reference value is closer to -1 than the first preset requirement, it can be explained that the trend of the double accumulation of the current difference on both sides of the corresponding line is close to a completely opposite state, so it can be judged that the corresponding is a completely negative correlation, which can be explained as an out-of-zone fault, and the first response action is not to perform protection action.

[0127] S334: If the reference value is greater than 0 and the distance value is less than the first preset requirement, it is determined to be an in-zone fault, and a first response action of performing a protection action is obtained.

[0128] It can be understood that the obtained Pearson correlation coefficient r is compared with the set protection action criterion setting value 0, so as to identify the in-zone or out-of-zone faults occurring on the line. The corresponding protection action criterion is r>0. When it is determined to be an in-zone fault, the protection action is performed and the faulty line is cut off to protect the power grid line in time and reduce the degree of fault damage.

[0129] S4: If the first response action meets the preset requirements, a function is constructed based on the station-side current and / or the system-side current to obtain an action function, and the action function is compared with a preset function to obtain a line longitudinal protection result.

[0130] It can be understood that when a fault occurs in the line, since the current waveforms when different devices fail are different, when the first response action meets the preset requirements, a function can be constructed according to the station side current and / or the system side current to obtain an action function, so as to compare the constructed action function with the preset function, thereby accurately determining the corresponding line longitudinal protection result and performing line protection in a timely manner.

[0131] Among them, the preset requirements are pre-set. For example, when an out-of-zone fault or an in-zone fault occurs, the first response action meets the preset requirements and fault verification is required. The corresponding action function can be constructed for subsequent comparison with the preset function to obtain the line longitudinal protection result. The action function is a waveform function corresponding to the station-side current or the system-side current, and the preset function is a waveform function preset according to different equipment configurations.

[0132] In some embodiments, the specific implementation of step S4 (if the first response action meets the preset requirements, a function is constructed based on the station-side current and / or the system-side current to obtain an action function, and the action function is compared with a preset function to obtain a line longitudinal protection result) includes:

[0133] S41, if it is determined to be an out-of-zone fault, the first response action meets the preset requirements, then the first moment of generating the first response action is obtained, the second moment is determined by reverse calculation according to the first preset time period, and the first time period is obtained based on the first moment and the second moment.

[0134] It should be noted that when it is determined that an out-of-zone fault occurs in the corresponding line, in order to further determine the corresponding equipment, for example, when the fault occurs in a specific device such as a storage device or a power generation device, the response time of the fault can be obtained so that the corresponding action function can be constructed later to improve the accuracy of the fault judgment.

[0135] Among them, the first moment is the moment of the response action, the first preset duration is the pre-set response duration, the second moment is the moment value corresponding to the first preset time before the first moment, and the first time period is the time period between the first moment and the second moment, so that the corresponding action function can be constructed later according to the first time period.

[0136] S42: Acquire power information on the system side within a first time period to obtain a first action function, where the first action function includes first sub-functions of different phases.

[0137] It can be understood that, since the corresponding device may use three-phase electricity or four-phase electricity, it contains multiple phase information, so the corresponding first action function has first sub-functions with different phases.

[0138] The first action function is a function of the electric energy information of the system side in the first time period, and the first sub-function is a function of the corresponding phase electric energy information.

[0139] S43, comparing the first action function with a first preset function to obtain a first comparison result, and determining an action device based on the comparison result to obtain a line longitudinal protection result.

[0140] It can be understood that by comparing the first action function with the first preset function, a first comparison result can be obtained. For example, when the first action function is compared with the first preset function, when there is a difference between the first sub-function corresponding to the A phase and the first preset function, it can be determined that the phase power information of the corresponding equipment has a fault, thereby determining the corresponding line longitudinal protection result.

[0141] The first comparison result is a display result after comparing the first action function with the first preset function, for example, the structures may be the same or different.

[0142] In some embodiments, the specific implementation of step S43 (comparing the first action function with the first preset function to obtain a first comparison result, and determining the action device based on the comparison result to obtain the line longitudinal protection result) includes:

[0143] S431, splitting and processing the first sub-functions of different phases according to preset time intervals to obtain multiple first function segments, and labeling them according to the time sequence of the first function segments to obtain a multi-dimensional label for each first function segment, wherein the multi-dimensional label includes a first phase dimension number and a first function segment sequence number.

[0144] It is understandable that in order to make the comparison structure more accurate, the first sub-function may be segmented, and the obtained multiple first function segments may be multi-dimensionally labeled to facilitate subsequent rapid comparison of information.

[0145] Among them, the preset time interval is a pre-set interval time period for segmentation, the first function segment is the function segment after the first sub-function is segmented, the multi-dimensional label is the label corresponding to each first function segment, and contains multiple dimensional information, such as corresponding phase information and timing sequence, that is, the corresponding multi-dimensional label can be A1, A2, so that A1 can be expressed as the first first function segment corresponding to the A phase, A2 can be expressed as the second first function segment corresponding to the A phase, the first phase dimension number is the label corresponding to the phase dimension corresponding to the first function segment, such as A, B, C, and the first function segment sequence number is the timing sequence of the first function segment in the corresponding first sub-function, such as 1, 2, 3, 4, etc.

[0146] S432, calculating the phase difference of the first sub-functions with different phases to obtain a plurality of phase difference groups.

[0147] It can be understood that the phase difference is the phase difference value corresponding to different first sub-functions, and the phase difference group is the phase combination corresponding to the calculated phase difference. For example, when the phase difference between phase A and phase B is π, the corresponding phase difference group is (phase A, phase B).

[0148] S433: Based on the first phase dimension number and the first function segment sequence number, determine the preset function segment corresponding to each first function segment in the first preset function.

[0149] It can be understood that according to the first phase dimension number and the first function segment sequence number, a preset function segment corresponding to the first function segment can be determined within the first preset function, so that the corresponding information can be compared subsequently, thereby improving the accuracy of the comparison result.

[0150] The preset function segment is a function segment in the first preset function.

[0151] S434, obtaining a first comparison result based on a fusion comparison of the first function segment, the preset function segment, and the phase difference of the phase difference group, and determining an action device based on the first comparison result to obtain a line longitudinal protection result.

[0152] It can be understood that the first function segment in the first sub-function is compared with the corresponding preset function segment, and at the same time, each phase difference group in the first action function is compared with the phase difference corresponding to the phase difference group in the first preset function. Through multi-dimensional comparison, the first comparison result is determined, thereby improving the accuracy of the line longitudinal protection result corresponding to the action device.

[0153] In some embodiments, the specific implementation of step S434 (obtaining a first comparison result based on the fusion comparison of the first function segment, the preset function segment, and the phase difference of the phase difference group, and determining the action device based on the first comparison result to obtain the line longitudinal protection result) includes:

[0154] S4341, taking each first function segment and preset function segment with the same multi-dimensional label as a function group, calculating the first slope and preset slope of the first function segment and preset function segment in the function group, and obtaining the first difference between the first slope and the preset slope.

[0155] It can be understood that the function group is a combination of the first function segment and the preset function segment corresponding to the same multi-dimensional label, the first slope is the slope of the first function segment in the function group, the preset slope is the slope of the preset function segment, and the first difference is the difference between the first slope and the preset slope.

[0156] It is not difficult to understand that, when the first difference is smaller, the corresponding first slope is closer to the preset slope, so that the corresponding comparison result can be determined more accurately to perform line protection.

[0157] S4342, calculating the extreme value difference between each first sub-function and a preset sub-function.

[0158] It can be understood that when the difference between the extreme values ​​of the first sub-function and the preset sub-function is smaller, it means that the equipment corresponding to the first sub-function is more similar to the equipment corresponding to the first preset function, and the corresponding fault similarity coefficients are closer, so as to perform line protection. When the extreme value difference is larger, the corresponding faults are less similar.

[0159] The preset sub-function is a sub-function with a corresponding different phase in the first preset function, and the extreme value difference is a difference between an extreme value of the first sub-function and an extreme value of the preset sub-function.

[0160] S4343, obtain the first similarity based on the fusion comparison of the first difference, the phase difference of each phase difference group, and the extreme value difference of each phase difference group, determine the faulty device corresponding to the first similarity with the largest value as the first comparison result, and determine the action device based on the faulty device to obtain the line longitudinal protection result.

[0161] It can be understood that the first similarity is the similarity calculated by fusion comparison of the first difference, the phase difference of each phase difference group and the corresponding extreme value difference, and the faulty device corresponding to the first similarity with the largest value is taken as the faulty device result compared, so as to determine the equipment that needs to be protected and obtain the line longitudinal protection result, so as to accurately determine the faulty device for line protection.

[0162] In another embodiment, the specific implementation of step S4 (if the first response action meets the preset requirements, a function is constructed based on the station-side current and / or the system-side current to obtain a first action function, and the first action function is compared with a preset function to obtain a line longitudinal protection result) includes:

[0163] S44, if it is determined to be an in-zone fault, the first response action meets the preset requirements, then the third moment of generating the first response action is obtained, the fourth moment is determined by reverse calculation according to the second preset time period, and the second time period is obtained based on the third moment and the fourth moment.

[0164] It is understandable that when the corresponding fault is determined to be an intra-zone fault, in order to further determine the specific device where the fault occurs, the response time of the fault can be obtained so as to subsequently construct the corresponding action function to improve the accuracy of fault judgment.

[0165] Among them, the third moment is the moment of response action corresponding to the fault in the area, the second preset duration is the pre-set response duration, the fourth moment is the moment value corresponding to the second preset time before the third moment, and the second time period is the time period between the third moment and the fourth moment, so that the corresponding second action function can be constructed later according to the second time period.

[0166] S45, acquiring the electric energy information at the station side in a second time period to obtain a second action function, where the second action function includes second sub-functions with different phases.

[0167] It can be understood that the station side is the energy supply equipment side in the power grid line, the second action function is the function corresponding to the power information of the station side in the second time period, and the second sub-function is the function of the corresponding different phases in the second action function.

[0168] It is not difficult to understand that the equipment on the station side may use multi-phase electricity, so the corresponding second action function has multiple sub-functions with different phases.

[0169] S46, comparing the second action function with a second preset function to obtain a second comparison result, verifying the second comparison result to obtain a verified second comparison result, and determining the action device based on the verified second comparison result to obtain a line longitudinal protection result.

[0170] It can be understood that by comparing the second action function with the second preset function, a corresponding second comparison result can be obtained, and then the line longitudinal protection result corresponding to the action device can be determined, so as to accurately determine the specific faulty equipment and perform timely line protection.

[0171] The second preset function is a pre-set electric energy information function for comparing and determining faults within the area, and the second comparison result is a result of comparing the function of the device determined to be a fault within the area.

[0172] In some embodiments, the specific implementation of step S46 (comparing the second action function with the second preset function to obtain a second comparison result, verifying the second comparison result to obtain a verified second comparison result, and determining the action device based on the verified second comparison result to obtain the line longitudinal protection result) includes:

[0173] S461, splitting and processing the second sub-functions of different phases according to preset time intervals to obtain multiple second function segments, and labeling them according to the time sequence of the second function segments to obtain a multi-dimensional label for each second function segment, wherein the multi-dimensional label includes a second phase dimension number and a second function segment sequence number.

[0174] It can be understood that the second function segment is a function segment obtained by dividing the second sub-function by a preset time interval, and each second function segment has a corresponding multi-dimensional label, and the multi-dimensional label includes a second phase dimension number and a second function segment sequence number, wherein the second phase dimension number is the label of the phase dimension corresponding to the second sub-function segment, and the second function segment sequence number is the sequence number of the second sub-function segment in the corresponding second sub-function arranged according to time sequence.

[0175] S462, calculating the phase difference of the second sub-functions with different phases to obtain a plurality of phase difference groups.

[0176] It can be understood that the difference of the second sub-functions with different phases is calculated to obtain the phase difference and the corresponding phase difference group. The specific implementation process is consistent with the phase difference and phase difference group of the first sub-function mentioned above, and will not be repeated here.

[0177] S463: Based on the second phase dimension number and the second function segment sequence number, determine the preset function segment corresponding to each second function segment in the second preset function.

[0178] It can be understood that the corresponding preset function segment can be determined in the second preset function through the second phase dimension number corresponding to the second function segment and the second function segment sequence number, so as to facilitate subsequent information comparison, thereby improving the accuracy of the comparison result.

[0179] The preset function segment is a function segment in the second preset function.

[0180] S464, based on the phase difference fusion comparison of the second function segment, the preset function segment, and the phase difference group, a second comparison result is obtained, a third function on the system side corresponding to the second action function is obtained, and the second action function is verified based on the third function to obtain a verified second comparison result.

[0181] It should be noted that since a failure in the energy supply equipment will have an impact on the system side, the result can be verified through a third function on the system side to improve the accuracy of the comparison result, so that line protection can be carried out in a timely manner.

[0182] It can be understood that the second function segment in the second sub-function is compared with the corresponding preset function segment, and at the same time, each phase difference group in the second action function is compared with the phase difference corresponding to the phase difference group in the second preset function. Through multi-dimensional comparison, the second comparison result is determined, so as to obtain the third function on the system side corresponding to the second action function, and verify the third function with the second action function, so as to improve the accuracy of the line longitudinal protection result corresponding to the action device.

[0183] The third function is the electric energy information function on the system side corresponding to the fault in the area.

[0184] In some embodiments, the specific implementation of step S464 (obtaining a second comparison result based on the fusion comparison of the second function segment, the preset function segment, and the phase difference group, obtaining a third function on the system side corresponding to the second action function, and verifying the second action function based on the third function to obtain a verified second comparison result) includes:

[0185] S4641, call the verification function corresponding to the second action function. If the verification function is empty, directly use the second action function as the second comparison result after verification processing.

[0186] It can be understood that the current verification function is the electric energy function corresponding to the station side. When the verification function is empty, it means that there is no function, that is, there is no need to verify the function, so the second action function can be used as the second comparison result after the verification process.

[0187] S4642, if the verification function is not empty, the third function and the verification function are respectively decomposed to obtain a third function segment and a verification function segment, and a second comparison result after verification is obtained based on a fusion comparison of the third function segment, the verification function segment, and the verification phase difference of the verification phase difference group.

[0188] It can be understood that when the verification function is not empty, the third function and the verification function can be divided according to the preset time interval to obtain a third function segment and a verification function segment and the third function segment can be labeled, so that the third function segment and the corresponding verification function segment can be compared, and the verification phase difference of the verification phase difference group can be fused and compared to obtain the verification result, that is, the second comparison result after verification.

[0189] Among them, the third function segment is the function segment after the third function is divided, the verification function segment is the function segment after the verification function is divided, the phase difference group is the function combination between the verification function segments corresponding to different phases, and the verification phase difference is the corresponding phase difference value in different verification functions.

[0190] In some embodiments, the specific implementation of step S4642 (decomposing the third function and the verification function to obtain the third function segment and the verification function segment respectively, and obtaining the verified second comparison result based on fusing and comparing the third function segment, the verification function segment, and the verification phase difference of the verification phase difference group) includes:

[0191] S46421, take each third function segment and verification function segment with the same multi-dimensional label as a verification function group, calculate the third slope and verification slope of the third function segment and verification function segment, and obtain the verification difference between the third slope and the verification slope.

[0192] It can be understood that the verification function group is a combination of a third function segment and a verification function segment with the same multi-dimensional label, the third slope is the function slope corresponding to the third function segment, the verification slope is the function slope corresponding to the verification function segment, and the verification difference is the difference between the third slope and the verification slope.

[0193] It is not difficult to understand that, when the verification difference is smaller, the corresponding third slope and the verification slope are closer, so that the corresponding comparison result can be determined more accurately to perform line protection.

[0194] S46422, calculate the extreme value difference between each third sub-function and the verification sub-function.

[0195] It can be understood that when the difference between the extreme values ​​of the third sub-function and the verification sub-function is smaller, it means that the equipment corresponding to the third sub-function is more similar to the equipment corresponding to the verification function, and the corresponding fault similarity coefficients are closer, so as to facilitate line protection. When the extreme value difference is larger, the corresponding functions are less similar.

[0196] The verification sub-function is a sub-function with a corresponding different phase in the verification function, and the extreme value difference is a difference between the extreme value of the third sub-function and the extreme value of the verification sub-function.

[0197] S46423, based on the verification difference, the verification phase difference of each verification phase difference group, and the verification extreme value difference of each verification phase difference group, the verification similarity is obtained by fusion comparison. If the verification similarity is greater than the verification preset value, it is judged that the verification result passes, and a second comparison result of the verification result passing is obtained.

[0198] It can be understood that the verification similarity is the similarity value after verification of the comparison result, and is the similarity calculated by fusing and comparing the verification difference, the verification phase difference of each verification phase difference group and the verification extreme value difference of each verification phase difference group. When the verification similarity is greater than the verification preset value, it can be said that the corresponding result similarity is high, and the function and the corresponding device are close, so it can be judged that the verification result passes, that is, it can be said that the corresponding judgment result is correct, and then the second comparison result that passes the verification result can be obtained.

[0199] It is not difficult to understand that when the fault is an in-zone fault, it can be explained that the corresponding equipment inside the station has a fault problem, and the function inside the station side can be compared with the corresponding preset function to determine the corresponding suspected equipment with a fault. After the corresponding suspicious equipment is determined, the equipment may affect the electric energy outside the station side. Therefore, the electric energy verification function corresponding to the equipment can be verified. If there is no verification function, no verification is performed. If there is a verification function, further verification is performed, that is, the accuracy is verified according to the verification function corresponding to different equipment attributes. When the verification function is verified for similarity with the function outside the station side, when the verification similarity is greater than the preset value of the judgment, it can be explained that the corresponding determined equipment is correct, so as to improve the accuracy of determining the faulty equipment.

[0200] The present invention also provides a storage medium, in which a computer program is stored. When the computer program is executed by a processor, it is used to implement the methods provided by the various embodiments described above.

[0201] Among them, the storage medium can be a computer storage medium or a communication medium. The communication medium includes any medium that facilitates the transmission of a computer program from one place to another. The computer storage medium can be any available medium that can be accessed by a general-purpose or special-purpose computer. For example, the storage medium is coupled to the processor so that the processor can read information from the storage medium and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and the storage medium can be located in an application-specific integrated circuit (Application Specific Integrated Circuits, referred to as: ASIC). In addition, the ASIC can be located in a user device. Of course, the processor and the storage medium can also exist in a communication device as discrete components. The storage medium can be a read-only memory (ROM), a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, and an optical data storage device, etc.

[0202] The present invention also provides a program product, which includes an execution instruction, which is stored in a storage medium. At least one processor of a device can read the execution instruction from the storage medium, and at least one processor executes the execution instruction so that the device implements the methods provided in the above various embodiments.

[0203] In the above-mentioned terminal or server embodiments, it should be understood that the processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), etc. A general-purpose processor may be a microprocessor or any conventional processor. The steps of the method disclosed in the present invention may be directly implemented as being executed by a hardware processor, or may be executed by a combination of hardware and software modules in the processor.

[0204] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A line pilot protection method based on the similarity of current differential double cumulative quantities, characterized in that: include: The line of the energy storage new energy station is divided and processed to obtain the new energy station side and the system side, and the station side current and the system side current of the new energy station side and the system side are obtained respectively based on the current transformer; The instantaneous difference components of the station-side current and the system-side current are calculated respectively to obtain the station-side difference component and the system-side difference component, and the accumulation of the station-side difference component and the system-side difference component within a preset period is calculated to obtain the station-side cumulative amount and the system-side cumulative amount; Performing multiple differential accumulations based on the station-side cumulative amount and the system-side cumulative amount, and performing Pearson similarity calculation to obtain a reference value, and obtaining a first response action based on the reference value; If the first response action meets the preset requirements, a function is constructed based on the station-side current and / or the system-side current to obtain an action function, and the action function is compared with the preset function to obtain a line longitudinal protection result.

2. The line pilot protection method based on current differential double cumulative similarity according to claim 1 is characterized in that: The instantaneous difference components of the station-side current and the system-side current are calculated respectively to obtain the station-side difference component and the system-side difference component, and the accumulation of the station-side difference component and the system-side difference component within a preset period is calculated to obtain the station-side cumulative amount and the system-side cumulative amount, including: Obtain the current sampling values ​​of the station-side current at adjacent time points and perform difference calculation to obtain the station-side difference component; Obtaining current sampling values ​​of the system side current at adjacent time points and performing difference calculation to obtain a system side difference component; The station-side differential quantities of all time points within a preset period are counted to obtain the station-side cumulative quantities; The system side differential quantity at all time points within a preset period is counted to obtain the system side cumulative quantity.

3. The line pilot protection method based on current differential double cumulative similarity according to claim 2 is characterized in that: The method of performing multiple differential accumulations based on the station-side cumulative amount and the system-side cumulative amount, and performing Pearson similarity calculation to obtain a reference value, and obtaining a first response action based on the reference value, includes: Double cumulative values ​​are calculated for the station side cumulative amount and the system side cumulative amount respectively, and a station side set and a system side set are generated based on the time series based on the double cumulative amount on the station side and the double cumulative amount on the system side; The station side set and the system side set respectively contain the station side double cumulative amount and the system side double cumulative amount sorted in time series, and the number of elements in the station side set and the system side set is the same as the number of samples in one power frequency cycle; The station side set and the system side set are processed based on Pearson similarity calculation to obtain a reference value, and a first response action is obtained based on the reference value.

4. The line pilot protection method based on current differential double cumulative similarity according to claim 3 is characterized in that: The step of processing the station side set and the system side set based on the Pearson similarity calculation to obtain a reference value, and obtaining a first response action based on the reference value includes: The station side set and the system side set are respectively used as two groups of input vectors to perform Pearson similarity calculation to obtain the Pearson similarity coefficient. The value range of the Pearson correlation coefficient is [-1,1]; Obtaining a reference value based on the value of the Pearson similarity coefficient; If the distance between the reference value and -1 is less than the first preset requirement, it is judged as an out-of-zone fault, and a first response action of not performing a protection action is obtained; If the reference value is greater than 0 and the distance value is less than the first preset requirement, it is determined to be an in-zone fault, and a first response action of performing a protection action is obtained.

5. The line pilot protection method based on current differential double cumulative similarity according to claim 4 is characterized in that: If the first response action meets the preset requirements, a function is constructed based on the station-side current and / or the system-side current to obtain an action function, and the action function is compared with a preset function to obtain a line longitudinal protection result, including: If it is determined to be an out-of-zone fault, the first response action meets the preset requirements, then the first time of generating the first response action is obtained, the second time is determined by reverse calculation according to the first preset time period, and the first time period is obtained based on the first time and the second time; Acquiring power information on the system side within a first time period to obtain a first action function, wherein the first action function includes first sub-functions of different phases; The first action function is compared with a first preset function to obtain a first comparison result, and an action device is determined based on the comparison result to obtain a line longitudinal protection result.

6. The line pilot protection method based on current differential double cumulative similarity according to claim 5 is characterized in that: The step of comparing the first action function with a first preset function to obtain a first comparison result, and determining an action device based on the comparison result to obtain a line longitudinal protection result includes: The first sub-functions of different phases are segmented and processed according to a preset time interval to obtain a plurality of first function segments, and each first function segment is numbered according to the time sequence of the first function segments to obtain a multi-dimensional number, wherein the multi-dimensional number includes a first phase dimension number and a first function segment sequence number; Calculating the phase difference of the first sub-functions with different phases to obtain a plurality of phase difference groups; Based on the first phase dimension number and the first function segment sequence number, determining a first preset function segment corresponding to each first function segment in the first preset function; A first comparison result is obtained by fusion comparison of the first function segment, the first preset function segment, and the phase difference of the phase difference group, and an action device is determined based on the first comparison result to obtain a line longitudinal protection result.

7. The line pilot protection method based on current differential double cumulative similarity according to claim 6 is characterized in that: The method of obtaining a first comparison result by fusing and comparing the first function segment, the first preset function segment, and the phase difference of the phase difference group, and determining an action device based on the first comparison result to obtain a line longitudinal protection result includes: Taking each first function segment and first preset function segment with the same multi-dimensional label as a function group, calculating the first slope and the preset slope of the first function segment and the first preset function segment in the function group, and obtaining a first difference between the first slope and the preset slope; Calculating the extreme value difference between each first sub-function and a preset sub-function; Based on the first difference, the phase difference of each phase difference group, and the extreme value difference of each phase difference group, a first similarity is obtained by fusion comparison, and the faulty device corresponding to the first similarity with the largest value is determined as the first comparison result. Based on the faulty device, the action device is determined to obtain the line longitudinal protection result.

8. The line pilot protection method based on current differential double cumulative similarity according to claim 4 is characterized in that: If the first response action meets the preset requirements, a function is constructed based on the station-side current and / or the system-side current to obtain a first action function, and the first action function is compared with a preset function to obtain a line longitudinal protection result, including: If it is determined to be an in-zone fault, the first response action meets the preset requirements, then the third time for generating the first response action is obtained, and the fourth time is determined by reverse calculation according to the second preset time period, and the second time period is obtained based on the third time and the fourth time; Acquiring the electric energy information at the station side in a second time period to obtain a second action function, wherein the second action function includes second sub-functions of different phases; The second action function is compared with a second preset function to obtain a second comparison result, the second comparison result is verified to obtain a verified second comparison result, and the action device is determined based on the verified second comparison result to obtain a line longitudinal protection result.

9. The line pilot protection method based on current differential double cumulative similarity according to claim 8, characterized in that: The step of comparing the second action function with a second preset function to obtain a second comparison result, performing verification processing on the second comparison result to obtain a verified second comparison result, and determining an action device based on the verified second comparison result to obtain a line longitudinal protection result includes: Segment the second sub-functions of different phases according to a preset time interval to obtain a plurality of second function segments, and label each second function segment according to the time sequence of the second function segments to obtain a multi-dimensional label, wherein the multi-dimensional label includes a second phase dimension number and a second function segment sequence number; Calculating phase differences of second sub-functions with different phases to obtain multiple phase difference groups; Based on the second phase dimension number and the second function segment sequence number, determining the second preset function segment corresponding to each second function segment in the second preset function; Based on the phase difference fusion comparison of the second function segment, the second preset function segment, and the phase difference group, a second comparison result is obtained, a third function on the system side corresponding to the second action function is obtained, and the second action function is verified based on the third function to obtain a verified second comparison result.

10. The line pilot protection method based on current differential double cumulative similarity according to claim 9, characterized in that: The method of obtaining a second comparison result based on the phase difference fusion comparison of the second function segment, the second preset function segment, and the phase difference group, obtaining a third function on the system side corresponding to the second action function, and verifying the second action function based on the third function to obtain a verified second comparison result includes: Calling the verification function corresponding to the second action function, if the verification function is empty, directly using the second action function as the second comparison result after verification processing; If the verification function is not empty, the third function and the verification function are respectively decomposed to obtain a third function segment and a verification function segment, and a second comparison result after verification is obtained by fusion comparison of the third function segment, the verification function segment and the verification phase difference group.

11. The line pilot protection method based on current differential double cumulative similarity according to claim 10, characterized in that: The third function and the verification function are decomposed to obtain a third function segment and a verification function segment respectively, and a second comparison result after verification is obtained by fusing and comparing the third function segment, the verification function segment, and the verification phase difference of the verification phase difference group, including: Taking each third function segment and verification function segment with the same multi-dimensional label as a verification function group, calculating the third slope and verification slope of the third function segment and verification function segment, and obtaining the verification difference between the third slope and the verification slope; Calculate the extreme value difference between each third sub-function and the verification sub-function; The verification similarity is obtained based on the verification difference, the verification phase difference of each verification phase difference group, and the verification extreme value difference of each verification phase difference group. If the verification similarity is greater than the verification preset value, the verification result is judged to be passed, and a second comparison result of the verification result passing is obtained.

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