Method and device for setting multi-value area of distance protection, equipment and storage medium

Abstract

The application discloses a setting method and device for distance protection multi-fixed value area, equipment and storage medium, which calculates the first short-circuit current flowing through the first protection node and the second short-circuit current of the second protection node when a short circuit occurs at the outlet of the first protection node according to the node admittance matrix and the node impedance matrix of the power grid, wherein the first protection node is the adjacent node of the second protection node; the short-circuit current trajectory similarity between multiple operation modes is calculated; the multiple operation modes are clustered based on the short-circuit current trajectory similarity, and multiple target fixed value areas are obtained, each target fixed value area corresponds to one or more operation modes, so that one-to-many matching of protection fixed values and operation modes is realized, so that the increasing operation modes can be effectively coped with; finally, the particle swarm optimization algorithm is used to perform fixed value optimization calculation on each target fixed value area respectively, and a fixed value calculation result is obtained. The speed of protection fixed value setting is improved, and the risk of protection node misoperation is reduced.

Description

Technical Field

[0001] This application relates to the field of relay protection setting calculation technology, and in particular to a method, apparatus, equipment and storage medium for setting multiple setting zones of distance protection. Background Technology

[0002] Relay protection, as the first line of defense for the safe and stable operation of the power grid, plays an indispensable role in quickly and selectively isolating faults and ensuring the safe and stable operation of the system. Modern ultra-high voltage line backup protection typically includes distance protection and zero-sequence current protection. Zero-sequence current protection usually serves as a supplement to distance protection, used only to clear high-resistance grounding faults. Distance protection is usually set in a tiered, coordinated manner. However, with the development of the power economy, the continuous expansion of the power grid, and the increasing complexity of power grid operation modes, the protection settings calculated using the traditional setting mode of "one set of settings to handle all operating modes" are unlikely to achieve optimal performance.

[0003] Currently, some technologies propose using a one-to-one matching between protection settings and operating modes in online setting to significantly improve setting performance. However, online setting has high real-time requirements; data acquisition, topology analysis, and setting calculations all require time, and this time is closely related to system scale. When the system scale reaches a certain level, existing online setting systems struggle to meet real-time requirements, making it difficult to achieve a one-to-one match between protection settings and operating modes. Therefore, a setting calculation method specifically for distance protection is urgently needed to achieve the matching between protection settings and operating modes. Summary of the Invention

[0004] This application provides a method, apparatus, device, and storage medium for setting multiple setting zones for distance protection, in order to solve the technical problem that current online setting is unable to cope with the increasing number of operating modes.

[0005] To address the aforementioned technical problems, firstly, this application provides a method for setting multiple setting zones for distance protection, comprising:

[0006] Based on the node admittance matrix and node impedance matrix of the power grid, calculate the first short-circuit current flowing through the first protection node and the second short-circuit current flowing through the second protection node when a short circuit occurs at the outlet of the first protection node, where the first protection node is an adjacent node of the second protection node.

[0007] Based on the first short-circuit current and the second short-circuit current, the similarity of short-circuit current trajectories among various operating modes is calculated.

[0008] Based on the similarity of short-circuit current trajectories, multiple operating modes are clustered to obtain multiple target setpoint regions, each of which corresponds to one or more operating modes;

[0009] Using the particle swarm optimization algorithm, the constant value optimization calculation is performed for each target constant value region to obtain the constant value calculation result.

[0010] In some implementations, based on the node admittance matrix and node impedance matrix of the power grid, the first short-circuit current flowing through the first protection node and the second short-circuit current flowing through the second protection node when a short circuit occurs at the outlet of the first protection node are calculated, including:

[0011] Calculate the node admittance matrix and node impedance matrix based on the power grid node data;

[0012] Based on the nodal admittance matrix and the nodal impedance matrix, calculate the first short-circuit current and the second short-circuit current. The calculation of the first short-circuit current is expressed as follows:

[0013] i a =(1-Z) a,n / Z n,n )×Y a,n ;

[0014] The calculation of the second short-circuit current is expressed as follows:

[0015] i s =[(1-Z s,n / Z n,n )-(1-Z a,n / Z n,n )]×Y s,a ;

[0016] Among them, i a Z represents the first short-circuit current. a,n Z represents the mutual impedance between the first protection node a and the outlet n in the node impedance matrix. n,n Z represents the self-impedance of outlet n in the nodal impedance matrix. s,n Y represents the mutual impedance between the second protection node s and the outlet n in the node impedance matrix. a,n Y represents the mutual admittance between the first protection node a and the outlet n in the node admittance matrix. s,a Let be the mutual admittance between the first protected node a and the second protected node s in the node admittance matrix.

[0017] In some implementations, the short-circuit current trajectory similarity between various operating modes is calculated based on the first short-circuit current and the second short-circuit current, including:

[0018] Based on the first short-circuit current and the second short-circuit current, the first short-circuit current trajectory of the first protection node and the second short-circuit current trajectory of the second protection node are determined under various operating modes, respectively.

[0019] Based on the first and second short-circuit current trajectories, the similarity of short-circuit current trajectories among various operating modes is calculated.

[0020] In some implementations, based on the first and second short-circuit current trajectories, the similarity of short-circuit current trajectories among various operating modes is calculated, including:

[0021] Using a preset similarity formula, the similarity between the short-circuit current trajectories is calculated based on the first and second short-circuit current trajectories. The preset similarity formula is as follows:

[0022]

[0023] in, The similarity of the short-circuit current trajectories between operating mode l and operating mode c. The weighted Euclidean distance of the short-circuit current trajectory of the first protection node a under operating mode l and operating mode c is given. w is the weighted Euclidean distance of the short-circuit current trajectory of the second protection node s under operating mode l and operating mode c. j These are the weighting coefficients. For the neighboring protected node q of protected node p j When a short-circuit fault occurs at the outlet, the Euler-Symmetric distance of the short-circuit current at the first protection node a under operating mode l and operating mode c. For the neighboring protected node q of protected node p j When a short-circuit fault occurs at the outlet, the Euler distance of the short-circuit current of the second protection node s under operating mode l and operating mode c.

[0024] In some implementations, multiple operating modes are clustered based on the similarity of short-circuit current trajectories to obtain multiple target setpoint regions, including:

[0025] For each operating mode, a first short-circuit current and a second short-circuit current under each operating mode are combined into a cluster sample to obtain a cluster sample set;

[0026] From the cluster sample set, several cluster samples are randomly selected as cluster centers, and each cluster center corresponds to a fixed value region;

[0027] Based on the similarity of short-circuit current trajectories between clustered samples and cluster centers, the clustered sample set is iteratively clustered until the preset number of iterations or the fixed value region no longer changes, resulting in multiple target fixed value regions.

[0028] In some implementations, each iteration of clustering includes the following steps:

[0029] For each cluster sample other than the cluster center, based on the short-circuit current trajectory similarity between the cluster sample and the cluster center, the first target cluster center with the smallest short-circuit current trajectory similarity with the cluster sample is determined, and the cluster sample is assigned to the fixed value region corresponding to the first target cluster center.

[0030] If the preset number of iterations is not reached or the fixed value area changes, the average value of the clustered samples in each fixed value area is calculated, and the average value is used as the new cluster center. The new cluster center is used as the cluster center for the next iteration of clustering.

[0031] In some implementations, the particle swarm optimization algorithm is used to perform constant value optimization calculations for each constant value region, obtaining constant value calculation results, including:

[0032] For each fixed value zone, using the protection nodes in the power grid as particles, initialize the initial velocity and initial position of all particles;

[0033] Calculate the fitness of each particle and determine the individual optimal solution and the global optimal solution for each particle.

[0034] Update the velocity and position of each particle, and continue to determine the individual optimal solution and the global optimal solution for each particle until the preset number of iterations is reached to obtain the result of the constant value calculation.

[0035] Secondly, this application also provides a distance protection multi-setting zone setting device, comprising:

[0036] The first calculation module is used to calculate the first short-circuit current flowing through the first protection node and the second short-circuit current flowing through the second protection node when a short circuit occurs at the outlet of the first protection node, based on the node admittance matrix and node impedance matrix of the power grid, wherein the first protection node is an adjacent node of the second protection node.

[0037] The second calculation module is used to calculate the short-circuit current trajectory similarity between multiple operating modes based on the first short-circuit current and the second short-circuit current.

[0038] The clustering module is used to cluster multiple operating modes based on the similarity of short-circuit current trajectories to obtain multiple target setpoint regions, each of which corresponds to one or more operating modes.

[0039] The optimization module is used to perform constant value optimization calculations for each target constant value region using the particle swarm optimization algorithm, and obtain the constant value calculation results.

[0040] Thirdly, this application also provides a computer device, including a processor and a memory, the memory being used to store a computer program, which, when executed by the processor, implements the distance protection multi-setting zone setting method as described in the first aspect.

[0041] Fourthly, this application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the distance protection multi-setting zone setting method as described in the first aspect.

[0042] Compared with the prior art, this application has at least the following beneficial effects:

[0043] By calculating the first short-circuit current flowing through the first protection node and the second short-circuit current flowing through the second protection node when a short circuit occurs at the outlet of the first protection node, based on the node admittance matrix and node impedance matrix of the power grid, the first protection node is an adjacent node of the second protection node. Based on the first and second short-circuit currents, the short-circuit current trajectory similarity among various operating modes is calculated. Based on the short-circuit current trajectory similarity, multiple operating modes are clustered to obtain multiple target setting regions. Each target setting region corresponds to one or more operating modes, thereby achieving a one-to-many match between protection settings and operating modes to effectively cope with the increasing number of operating modes. Finally, the particle swarm optimization algorithm is used to perform setting optimization calculations for each target setting region to obtain the setting calculation results. This application combines short-circuit current trajectory similarity and particle swarm optimization algorithm for setting value adjustment, improving the speed of protection setting value adjustment and reducing the risk of protection node maloperation. Attached Figure Description

[0044] Figure 1 This is a schematic flowchart illustrating the distance protection multi-setting zone setting method according to an embodiment of this application;

[0045] Figure 2 This is a schematic diagram of the power network topology shown in the embodiments of this application;

[0046] Figure 3 This is a schematic diagram of the structure of the distance protection multi-setting zone setting device shown in the embodiments of this application;

[0047] Figure 4 This is a schematic diagram of the structure of a computer device shown in an embodiment of this application. Detailed Implementation

[0048] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0049] Please refer to Figure 1 , Figure 1This is a flowchart illustrating a method for setting multiple distance protection settings in an embodiment of this application. The method for setting multiple distance protection settings in this application can be applied to computer devices, including but not limited to smartphones, laptops, tablets, desktop computers, physical servers, and cloud servers. Figure 1 As shown, the distance protection multi-setting zone setting method of this embodiment includes steps S101 to S104, which are described in detail below:

[0050] Step S101: Based on the node admittance matrix and node impedance matrix of the power grid, calculate the first short-circuit current flowing through the first protection node and the second short-circuit current flowing through the second protection node when a short circuit occurs at the outlet of the first protection node, wherein the first protection node is an adjacent node of the second protection node.

[0051] In this step, based on the power grid topology, the node admittance matrix and node impedance matrix are calculated. This allows for the calculation of the changed node short-circuit current when the protection settings need to be adjusted due to changes in the operating mode, such as power grid faults. This describes the changes and uses them to determine the current similarity between different operating modes, thereby classifying the different operating modes and providing a basis for subsequent matching of protection settings with multiple operating modes.

[0052] In some embodiments, step S101 includes:

[0053] Calculate the node admittance matrix and the node impedance matrix based on the power grid node data;

[0054] Based on the node admittance matrix and the node impedance matrix, the first short-circuit current and the second short-circuit current are calculated. The calculation of the first short-circuit current is expressed as follows:

[0055] i a =(1-Z) a,n / Z n,n )×Y a,n ;

[0056] The calculation of the second short-circuit current is expressed as follows:

[0057] i s =[(1-Z s,n / Z n,n )-(1-Z a,n / Z n,n )]×Y s,a ;

[0058] Among them, i a Z represents the first short-circuit current. a,n Z represents the mutual impedance between the first protection node a and the outlet n in the node impedance matrix.n,n Z represents the self-impedance of outlet n in the nodal impedance matrix. s,n Y represents the mutual impedance between the second protection node s and the outlet n in the node impedance matrix. a,n Y represents the mutual admittance between the first protection node a and the outlet n in the node admittance matrix. s,a Let be the mutual admittance between the first protected node a and the second protected node s in the node admittance matrix.

[0059] In this embodiment, under simulation conditions, one of the protection nodes of the power grid is selected sequentially as the second protection node s, and its adjacent protection node is called the first protection node a. A three-phase metallic short circuit is set at the outlet of the first protection node a, and the node admittance matrix and the node impedance matrix are calculated, wherein the node admittance matrix is:

[0060]

[0061] Where Y ii The sum of the admittances of the branches directly connected to protection node i is called the self-admittance, Y. ij The negative of the sum of the branch admittances between protection node i and protection node j is called the mutual admittance.

[0062] The node impedance matrix is ​​the inverse of the node admittance matrix, expressed as: Z = inv(Y).

[0063] Step S102: Based on the first short-circuit current and the second short-circuit current, calculate the short-circuit current trajectory similarity between multiple operating modes.

[0064] In this step, each operating mode corresponds to a first short-circuit current and a second short-circuit current. By determining the similarity of the short-circuit current trajectories between each pair of operating modes, the similarity of the two operating modes in terms of short-circuit current can be determined. Thus, the same protection setting method can be used to calculate the setting for two operating modes with similar short-circuit currents, achieving a one-to-many match between protection settings and operating modes, effectively coping with the increasing number of operating modes.

[0065] In some embodiments, calculating the short-circuit current trajectory similarity among multiple operating modes based on the first short-circuit current and the second short-circuit current includes:

[0066] Based on the first short-circuit current and the second short-circuit current, the first short-circuit current trajectory of the first protection node and the second short-circuit current trajectory of the second protection node are determined under various operating modes, respectively.

[0067] Based on the first short-circuit current trajectory and the second short-circuit current trajectory, the short-circuit current trajectory similarity between various operating modes is calculated.

[0068] In this embodiment, assuming the total number of distance protection nodes in the entire network is m and the total number of protection setting coordination pairs is n, the short-circuit current trajectory of the entire network under operation mode l can be described as follows:

[0069]

[0070]

[0071] in This represents the current trajectory flowing through the first protection node a in operating mode l. This represents the current trajectory flowing through the second protection node s in operating mode l. For the neighboring protected node q of protected node p j When a short circuit fault occurs at the outlet, the flow passes through the protection node q j The current, For the neighboring protected node q of protected node p j The current flowing through the protection node p when a short-circuit fault occurs at the outlet.

[0072] In some embodiments, calculating the short-circuit current trajectory similarity among various operating modes based on the first short-circuit current trajectory and the second short-circuit current trajectory includes:

[0073] Using a preset similarity formula, the similarity of the short-circuit current trajectories is calculated based on the first short-circuit current trajectory and the second short-circuit current trajectory. The preset similarity formula is as follows:

[0074]

[0075] in, The similarity of the short-circuit current trajectories between operating mode l and operating mode c. The weighted Euclidean distance of the short-circuit current trajectory of the first protection node a under operating mode l and operating mode c is given. w is the weighted Euclidean distance of the short-circuit current trajectory of the second protection node s under operating mode l and operating mode c. j These are the weighting coefficients. For the neighboring protected node q of protected node p j When a short-circuit fault occurs at the outlet, the Euler-Symmetric distance of the short-circuit current at the first protection node a under operating mode l and operating mode c. For the neighboring protected node q of protected node p j When a short-circuit fault occurs at the outlet, the Euler distance of the short-circuit current of the second protection node s under operating mode l and operating mode c.

[0076] Optionally, the protection of some important nodes can be enhanced by increasing the weighting coefficient to increase its impact on subsequent clustering. The short-circuit fault is a three-phase metallic short-circuit fault.

[0077] Step S103: Based on the short-circuit current trajectory similarity, cluster the various operating modes to obtain multiple target setpoint regions, each target setpoint region corresponding to one or more of the operating modes.

[0078] In this step, by using the short-circuit current characteristics of different operating modes, the similarity of the optimization methods between different operating modes when optimizing the settings is determined, thereby achieving a one-to-many match between protection setting optimization and operating modes.

[0079] In some embodiments, step S103 includes:

[0080] For each of the aforementioned operating modes, a first short-circuit current and a second short-circuit current under the aforementioned operating mode are combined into a cluster sample to obtain a cluster sample set;

[0081] From the clustered sample set, a number of clustered samples are randomly selected as cluster centers, and each cluster center corresponds to a fixed value region;

[0082] Based on the short-circuit current trajectory similarity between the clustered samples and the cluster centers, the clustered sample set is iteratively clustered until a preset number of iterations or the fixed value region no longer changes, resulting in multiple target fixed value regions.

[0083] In this embodiment, each iteration of clustering includes the following steps:

[0084] For each cluster sample other than the cluster center, based on the short-circuit current trajectory similarity between the cluster sample and the cluster center, a first target cluster center with the smallest short-circuit current trajectory similarity to the cluster sample is determined, and the cluster sample is assigned to the fixed value region corresponding to the first target cluster center.

[0085] If the preset number of iterations is not reached or the fixed value region changes, the average value of the clustered samples in each fixed value region is calculated, and the average value is used as the new cluster center. The new cluster center is used as the cluster center for the next iteration of clustering.

[0086] In this embodiment, the K-Means algorithm is used to cluster operating modes based on the proposed short-circuit current trajectory similarity index: common operating modes generated by the power grid over a period of time are collected, and a large number of operating modes are generated for a specific network through offline simulation to include as many scenarios as possible. Two sets of short-circuit current vectors can be calculated for each operating mode: the current vector flowing through this protection and the current vector flowing through the adjacent protection. These two sets of vectors are merged into one vector group, considered as a sample, and the K-Means clustering algorithm is used to cluster the operating modes. The steps are as follows:

[0087] 3.1 Randomly select k points from the sample as the centers of k initial sample clusters;

[0088] 3.2 Calculate the short-circuit current trajectory similarity index between each remaining sample point and the k cluster centers. Find the cluster center of the sample with the lowest similarity index, and assign this sample to the corresponding cluster;

[0089] 3.3 Calculate the average value of the samples within each cluster and define it as the new cluster center;

[0090] 3.4 Repeat steps 3.2-3.3 until the samples within the cluster no longer change or the preset number of iterations is reached.

[0091] Step S104: Using the particle swarm optimization algorithm, perform fixed value optimization calculations for each of the target fixed value regions to obtain the fixed value calculation results.

[0092] In this embodiment, each target setpoint range corresponds to one or more operating modes, so that the protection setpoint optimization can be applied to multiple operating modes.

[0093] In some embodiments, step S104 includes:

[0094] For each of the setpoint regions, using the protection nodes in the power grid as particles, initialize the initial velocity and initial position of all particles;

[0095] Calculate the fitness of each particle and determine the individual optimal solution and the global optimal solution for each particle.

[0096] Update the velocity and position of each particle, and continue to determine the individual optimal solution and the global optimal solution for each particle until the preset number of iterations is reached to obtain the value calculation result.

[0097] In this embodiment, the particle swarm optimization algorithm is used to perform constant value optimization calculations on each cluster after clustering; the constant value optimization calculations for the k clusters are independent of each other, and the following explanation is based on one of the clusters:

[0098] 4.1 Initialize all particles, setting the size, initial velocity, and initial position of the particle swarm;

[0099] 4.2 Calculate the fitness function of each particle and find the individual optimal solution and the global optimal solution, where the fitness function is shown below;

[0100]

[0101] Where M is the fitness value, I is the number of definite-time protections in the system, J is the number of definite-time protection delay periods, and t i (j) represents the operating time of the j-th delay period of the time-limited protection i. The sum of all additional protection times that do not satisfy the differential constraint, ∑ k t sen The sum of all additional protection times that do not meet the sensitivity constraints, ∑ k t sel The sum of additional times for all protections that do not meet the selective constraints.

[0102] 4.3 Update the velocity and position of all particles using the formula shown below;

[0103] v i =w×v i +c1×rand()×(pbest i -x i )+c2×rand()×(gbest i -x i )

[0104] x i =x i +v i ;

[0105] In the formula, i = 1, 2, 3…N, where i is the index of the particle in this group, v i It is the particle's velocity, x i The current position of the particle is , rand() is a random number between (0, 1), c1 and c2 are learning factors, and w is the inertia factor.

[0106] 4.4 If the termination condition is met, the process will terminate; otherwise, proceed to 4.2 and continue execution.

[0107] As an example, and not a limitation, the IEEE 39-node system is used as an example. The system topology diagram is as follows: Figure 2 As shown. The offline simulation uses the N-1 principle commonly used in power grid analysis to generate the operating mode, that is, it considers the operating mode generated after 46 lines are out of service (in actual applications, the number of lines that are out of service at the same time can be increased or decreased).

[0108] The number of fixed-value zones was set to 6 (which can be adjusted according to actual needs). The results of clustering the 46 considered operating modes are shown in the table below:

[0109]

[0110] A particle swarm optimization (PSO) tuning model is established based on minimizing the sum of the total network protection action time and the time of loss of selectivity. The initial parameters for the PSO algorithm are set as follows: total number of particles N = 100, individual learning factor c1 = 2, social learning factor c2 = 2, and maximum number of iterations k. max =100, the inertia factor w adopts a linear decreasing weight strategy, as shown in the following formula:

[0111]

[0112] Where w is the inertia factor for each iteration, w ini Let w be the initial inertia factor, set to 0.9. end The inertia factor at the maximum number of iterations is set to 0.4, k. max is the maximum number of iterations, and k is the current number of iterations.

[0113] To verify the superiority of the proposed method, the protection setting calculation method of "one set of settings to handle all operating modes" (referred to as Method 1) is compared with the proposed method (referred to as Method 2). The results are shown in the table below, where the probability of losing selectivity is the maximum probability of losing selectivity among the considered operating modes:

[0114]

[0115] As shown in the table above, the proposed method significantly reduces the probability of protection losing selectivity compared to Method 1. Specifically, the probability of loss of selectivity for cluster C5 is reduced by 10.87%, and the maximum probability of loss of selectivity among all clusters is only the same as that of Method 1. Regarding the overall network protection action time, all six clusters show significant reductions, with the largest reduction being 14.18%. In summary, compared to the traditional protection setting calculation method that considers all operating modes with a single set of settings, the proposed method significantly improves the selectivity and speed of protection, greatly enhancing its ability to cope with extreme operating modes.

[0116] To implement the distance protection multi-setting zone setting method corresponding to the above method embodiments, in order to achieve the corresponding functions and technical effects, see [link to documentation]. Figure 3 , Figure 3This diagram illustrates a structural block diagram of a distance protection multi-setting zone setting device according to an embodiment of this application. For ease of explanation, only the parts relevant to this embodiment are shown. The distance protection multi-setting zone setting device provided in this embodiment includes:

[0117] The first calculation module 301 is used to calculate, based on the node admittance matrix and node impedance matrix of the power grid, the first short-circuit current flowing through the first protection node and the second short-circuit current flowing through the second protection node when a short circuit occurs at the outlet of the first protection node, wherein the first protection node is an adjacent node of the second protection node.

[0118] The second calculation module 302 is used to calculate the short-circuit current trajectory similarity between multiple operating modes based on the first short-circuit current and the second short-circuit current.

[0119] Clustering module 303 is used to cluster multiple operating modes based on the short-circuit current trajectory similarity to obtain multiple target setpoint regions, each target setpoint region corresponding to one or more of the operating modes;

[0120] The optimization module 304 is used to perform fixed-value optimization calculations on each of the target fixed-value regions using the particle swarm optimization algorithm to obtain the fixed-value calculation results.

[0121] In some embodiments, the first computing module 301 is specifically used for:

[0122] Calculate the node admittance matrix and the node impedance matrix based on the power grid node data;

[0123] Based on the node admittance matrix and the node impedance matrix, the first short-circuit current and the second short-circuit current are calculated. The calculation of the first short-circuit current is expressed as follows:

[0124] i a =(1-Z) a,n / Z n,n )×Y a,n ;

[0125] The calculation of the second short-circuit current is expressed as follows:

[0126] i s =[(1-Z s,n / Z n,n )-(1-Z a,n / Z n,n )]×Y s,a ;

[0127] Among them, i a Z represents the first short-circuit current. a,n Z represents the mutual impedance between the first protection node a and the outlet n in the node impedance matrix.n,n Z represents the self-impedance of outlet n in the nodal impedance matrix. s,n Y represents the mutual impedance between the second protection node s and the outlet n in the node impedance matrix. a,n Y represents the mutual admittance between the first protection node a and the outlet n in the node admittance matrix. s,a Let be the mutual admittance between the first protected node a and the second protected node s in the node admittance matrix.

[0128] In some embodiments, the second computing module 302 includes:

[0129] The determining unit is configured to determine, based on the first short-circuit current and the second short-circuit current, the first short-circuit current trajectory of the first protection node and the second short-circuit current trajectory of the second protection node under various operating modes, respectively.

[0130] The calculation unit is used to calculate the short-circuit current trajectory similarity among various operating modes based on the first short-circuit current trajectory and the second short-circuit current trajectory.

[0131] In some embodiments, the computing unit is specifically used for:

[0132] Using a preset similarity formula, the similarity of the short-circuit current trajectories is calculated based on the first short-circuit current trajectory and the second short-circuit current trajectory. The preset similarity formula is as follows:

[0133]

[0134] in, The similarity of the short-circuit current trajectories between operating mode l and operating mode c. The weighted Euclidean distance of the short-circuit current trajectory of the first protection node a under operating mode l and operating mode c is given. w is the weighted Euclidean distance of the short-circuit current trajectory of the second protection node s under operating mode l and operating mode c. j These are the weighting coefficients. For the neighboring protected node q of protected node p j When a short-circuit fault occurs at the outlet, the Euler-Symmetric distance of the short-circuit current at the first protection node a under operating mode l and operating mode c. For the neighboring protected node q of protected node p j When a short-circuit fault occurs at the outlet, the Euler distance of the short-circuit current of the second protection node s under operating mode l and operating mode c.

[0135] In some embodiments, the clustering module 303 is specifically used for:

[0136] For each of the aforementioned operating modes, a first short-circuit current and a second short-circuit current under the aforementioned operating mode are combined into a cluster sample to obtain a cluster sample set;

[0137] From the clustered sample set, a number of clustered samples are randomly selected as cluster centers, and each cluster center corresponds to a fixed value region;

[0138] Based on the short-circuit current trajectory similarity between the clustered samples and the cluster centers, the clustered sample set is iteratively clustered until a preset number of iterations or the fixed value region no longer changes, resulting in multiple target fixed value regions.

[0139] In some embodiments, each iteration of clustering includes the following steps:

[0140] For each cluster sample other than the cluster center, based on the short-circuit current trajectory similarity between the cluster sample and the cluster center, a first target cluster center with the smallest short-circuit current trajectory similarity to the cluster sample is determined, and the cluster sample is assigned to the fixed value region corresponding to the first target cluster center.

[0141] If the preset number of iterations is not reached or the fixed value region changes, the average value of the clustered samples in each fixed value region is calculated, and the average value is used as the new cluster center. The new cluster center is used as the cluster center for the next iteration of clustering.

[0142] In some embodiments, the optimization module 304 is specifically used for:

[0143] For each of the setpoint regions, using the protection nodes in the power grid as particles, initialize the initial velocity and initial position of all particles;

[0144] Calculate the fitness of each particle and determine the individual optimal solution and the global optimal solution for each particle.

[0145] Update the velocity and position of each particle, and continue to determine the individual optimal solution and the global optimal solution for each particle until the preset number of iterations is reached to obtain the value calculation result.

[0146] The aforementioned distance protection multi-setting zone setting device can implement the distance protection multi-setting zone setting method of the above method embodiments. The options in the above method embodiments are also applicable to this embodiment, and will not be detailed here. The remaining contents of this application embodiment can be referred to the contents of the above method embodiments, and will not be repeated in this embodiment.

[0147] Figure 4 This is a schematic diagram of the structure of a computer device provided in an embodiment of this application. Figure 4 As shown, the computer device 4 of this embodiment includes: at least one processor 40 ( Figure 4 (Only one is shown in the diagram) a processor, a memory 41, and a computer program 42 stored in the memory 41 and executable on the at least one processor 40, which, when executing the computer program 42, implements the steps in any of the above method embodiments.

[0148] The computer device 4 can be a smartphone, tablet, desktop computer, cloud server, or other computing device. This computer device may include, but is not limited to, a processor 40 and a memory 41. Those skilled in the art will understand that... Figure 4 The computer device 4 is merely an example and does not constitute a limitation on the computer device 4. It may include more or fewer components than shown, or combine certain components, or different components, such as input / output devices, network access devices, etc.

[0149] The processor 40 may be a Central Processing Unit (CPU), or it may be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor.

[0150] In some embodiments, the memory 41 may be an internal storage unit of the computer device 4, such as a hard disk or memory of the computer device 4. In other embodiments, the memory 41 may be an external storage device of the computer device 4, such as a plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, etc., equipped on the computer device 4. Furthermore, the memory 41 may include both internal and external storage units of the computer device 4. The memory 41 is used to store the operating system, applications, bootloader, data, and other programs, such as the program code of the computer program. The memory 41 can also be used to temporarily store data that has been output or will be output.

[0151] In addition, embodiments of this application also provide a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps in any of the above method embodiments.

[0152] This application provides a computer program product that, when run on a computer device, enables the computer device to execute the steps described in the various method embodiments above.

[0153] In the several embodiments provided in this application, it will be understood that each block in the flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than those shown in the figures. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved.

[0154] If the aforementioned functions are implemented as software functional modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0155] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this application. It should be understood that the above descriptions are merely specific embodiments of this application and are not intended to limit the scope of protection of this application. In particular, it should be noted that any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application for those skilled in the art.

Claims

1. A method for setting multiple setting zones for distance protection, characterized in that, include: Based on the node admittance matrix and node impedance matrix of the power grid, calculate the first short-circuit current flowing through the first protection node and the second short-circuit current flowing through the second protection node when a short circuit occurs at the outlet of the first protection node, wherein the first protection node is an adjacent node of the second protection node. Based on the first short-circuit current and the second short-circuit current, calculate the short-circuit current trajectory similarity between multiple operating modes; Based on the short-circuit current trajectory similarity, multiple operating modes are clustered to obtain multiple target setpoint regions, and each target setpoint region corresponds to one or more of the operating modes. Using the particle swarm optimization algorithm, the constant value optimization calculation is performed on each of the target constant value regions to obtain the constant value calculation results; The calculation of short-circuit current trajectory similarity among various operating modes based on the first short-circuit current and the second short-circuit current includes: Based on the first short-circuit current and the second short-circuit current, the first short-circuit current trajectory of the first protection node and the second short-circuit current trajectory of the second protection node are determined under various operating modes, respectively. Based on the first short-circuit current trajectory and the second short-circuit current trajectory, calculate the short-circuit current trajectory similarity among the various operating modes; The step of calculating the short-circuit current trajectory similarity among various operating modes based on the first short-circuit current trajectory and the second short-circuit current trajectory includes: Using a preset similarity formula, the similarity of the short-circuit current trajectories is calculated based on the first short-circuit current trajectory and the second short-circuit current trajectory. The preset similarity formula is as follows: ； in, Operating mode Operating mode Similarity of short-circuit current trajectories between them First protection node In operation mode Operating mode The weighted Euclidean distance of the short-circuit current trajectory. As the second protection node In operation mode Operating mode The weighted Euclidean distance of the short-circuit current trajectory. These are the weighting coefficients. To protect nodes Adjacent protection nodes First protection node during short circuit fault at the outlet In operation mode Operating mode The Euler distance for the short-circuit current. To protect nodes Adjacent protection nodes Second protection node during short circuit fault at the outlet In operation mode Operating mode The Euler distance for the short-circuit current; Based on the short-circuit current trajectory similarity, clustering is performed on various operating modes to obtain multiple target setpoint regions, including: For each of the aforementioned operating modes, a first short-circuit current and a second short-circuit current under the aforementioned operating mode are combined into a cluster sample to obtain a cluster sample set; From the clustered sample set, a number of clustered samples are randomly selected as cluster centers, and each cluster center corresponds to a fixed value region; Based on the short-circuit current trajectory similarity between the clustered samples and the cluster centers, the clustered sample set is iteratively clustered until a preset number of iterations or the fixed value region no longer changes, resulting in multiple target fixed value regions. Each iteration of clustering includes the following steps: For each cluster sample other than the cluster center, based on the short-circuit current trajectory similarity between the cluster sample and the cluster center, a first target cluster center with the smallest short-circuit current trajectory similarity to the cluster sample is determined, and the cluster sample is assigned to the fixed value region corresponding to the first target cluster center. If the preset number of iterations is not reached or the fixed value region changes, the average value of the clustered samples in each fixed value region is calculated, and the average value is used as the new cluster center. The new cluster center is used as the cluster center for the next iteration of clustering.

2. The distance protection multi-setting zone setting method as described in claim 1, characterized in that, The calculation of the first short-circuit current flowing through the first protection node and the second short-circuit current flowing through the second protection node when a short circuit occurs at the outlet of the first protection node, based on the node admittance matrix and node impedance matrix of the power grid, includes: Calculate the node admittance matrix and the node impedance matrix based on the power grid node data; Based on the node admittance matrix and the node impedance matrix, the first short-circuit current and the second short-circuit current are calculated. The calculation of the first short-circuit current is expressed as follows: ； The calculation of the second short-circuit current is expressed as follows: ； in, Indicates the first short-circuit current. The first protected node in the node impedance matrix With exports mutual impedance between For the outlet in the nodal impedance matrix Self-impedance, The second protection node in the node impedance matrix With exports mutual impedance between The first protected node in the node admittance matrix With exports Mutual admittance between them The first protected node in the node admittance matrix With the second protection node Mutual admittance between them.

3. The distance protection multi-setting zone setting method as described in claim 1, characterized in that, The step of using the particle swarm optimization algorithm to perform constant value optimization calculations for each of the constant value regions, and obtaining constant value calculation results, includes: For each of the setpoint regions, using the protection nodes in the power grid as particles, initialize the initial velocity and initial position of all particles; Calculate the fitness of each particle and determine the individual optimal solution and the global optimal solution for each particle. Update the velocity and position of each particle, and continue to determine the individual optimal solution and the global optimal solution for each particle until the preset number of iterations is reached to obtain the value calculation result.

4. A distance protection multi-setting zone setting device, characterized in that, include: The first calculation module is used to calculate, based on the node admittance matrix and node impedance matrix of the power grid, the first short-circuit current flowing through the first protection node and the second short-circuit current flowing through the second protection node when a short circuit occurs at the outlet of the first protection node, wherein the first protection node is an adjacent node of the second protection node. The second calculation module is used to calculate the short-circuit current trajectory similarity between multiple operating modes based on the first short-circuit current and the second short-circuit current. The clustering module is used to cluster multiple operating modes based on the short-circuit current trajectory similarity to obtain multiple target setpoint regions, each target setpoint region corresponding to one or more of the operating modes; The optimization module is used to perform fixed-value optimization calculations on each of the target fixed-value regions using the particle swarm optimization algorithm to obtain the fixed-value calculation results. The second computing module includes: The determining unit is configured to determine, based on the first short-circuit current and the second short-circuit current, the first short-circuit current trajectory of the first protection node and the second short-circuit current trajectory of the second protection node under various operating modes, respectively. A calculation unit is used to calculate the short-circuit current trajectory similarity among various operating modes based on the first short-circuit current trajectory and the second short-circuit current trajectory. The computing unit is specifically used for: Using a preset similarity formula, the similarity of the short-circuit current trajectories is calculated based on the first short-circuit current trajectory and the second short-circuit current trajectory. The preset similarity formula is as follows: ； in, Operating mode Operating mode Similarity of short-circuit current trajectories between them First protection node In operation mode Operating mode The weighted Euclidean distance of the short-circuit current trajectory. As the second protection node In operation mode Operating mode The weighted Euclidean distance of the short-circuit current trajectory. These are the weighting coefficients. To protect nodes Adjacent protection nodes First protection node during short circuit fault at the outlet In operation mode Operating mode The Euler distance for the short-circuit current. To protect nodes Adjacent protection nodes Second protection node during short circuit fault at the outlet In operation mode Operating mode The Euler distance for the short-circuit current; The clustering module is specifically used for: For each of the aforementioned operating modes, a first short-circuit current and a second short-circuit current under the aforementioned operating mode are combined into a cluster sample to obtain a cluster sample set; From the clustered sample set, a number of clustered samples are randomly selected as cluster centers, and each cluster center corresponds to a fixed value region; Based on the short-circuit current trajectory similarity between the clustered samples and the cluster centers, the clustered sample set is iteratively clustered until a preset number of iterations or the fixed value region no longer changes, resulting in multiple target fixed value regions. Each iteration of clustering includes the following steps: For each cluster sample other than the cluster center, based on the short-circuit current trajectory similarity between the cluster sample and the cluster center, a first target cluster center with the smallest short-circuit current trajectory similarity to the cluster sample is determined, and the cluster sample is assigned to the fixed value region corresponding to the first target cluster center. If the preset number of iterations is not reached or the fixed value region changes, the average value of the clustered samples in each fixed value region is calculated, and the average value is used as the new cluster center. The new cluster center is used as the cluster center for the next iteration of clustering.

5. A computer device, characterized in that, It includes a processor and a memory, the memory being used to store a computer program, which, when executed by the processor, implements the distance protection multi-setting zone setting method as described in any one of claims 1 to 3.

6. A computer-readable storage medium, characterized in that, It stores a computer program that, when executed by a processor, implements the distance protection multi-setting zone setting method as described in any one of claims 1 to 3.

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