Site selection method, device, storage medium and electronic equipment for power grid ring closing device

Abstract

The present invention discloses a site selection method, device, storage medium and electronic device for a power grid closing device. Relating to the field of smart grids, the method comprises: obtaining multiple closing points in a target power grid, and voltage differences and phase angle differences corresponding to the multiple closing points; determining a first set of candidate locations for the closing device from the multiple closing points based on the voltage differences and phase angle differences corresponding to the multiple closing points; determining a second set of candidate locations for the closing device from the multiple closing points based on the equivalent impedances corresponding to the multiple closing points; and determining the installation location of the closing device based on the first set of candidate locations and the second set of candidate locations. The present invention solves the technical problem in the related art of incomplete consideration of factors when determining the installation location of the closing device, resulting in inaccurate closing location installation and, in turn, a low success rate of power grid closing switching.

Description

Technical Field

[0001] The present invention relates to the field of smart grids, and in particular to a site selection method, device, storage medium and electronic equipment for a power grid ring closing device. Background Art

[0002] In the related art, for some large regional power grids, due to the limitation of the breaking capacity of the circuit breaker of the main power grid, the busbar of the 220 kilovolt (kV) voltage level is disconnected, forming a grid partition with a 500kV ring network as the main grid frame and a 220kV ring network, so as to ensure that the short-circuit current of the power grid does not exceed the standard when a fault occurs, and the circuit breaker has the ability to isolate the fault by arcing. In some cases, such as when the power grid is changed before maintenance in spring and autumn and important guarantees, the power grid will often encounter busbar closing operations between grid partitions. When performing busbar closing operations between grid partitions, it is necessary to install a corresponding closing device at the closing point to perform the closing switching operation. However, in the related art, when determining the installation position of the closing device, the factors are not fully considered, resulting in inaccurate installation of the closing position, which in turn easily leads to a low success rate of closing and switching of the power grid.

[0003] To address the above-mentioned problems, no effective solutions have been proposed so far. Summary of the Invention

[0004] The embodiments of the present invention provide a site selection method, device, storage medium and electronic device for a power grid closing device, so as to at least solve the technical problem in the related art that when determining the installation location of the closing device, factors are not fully considered, resulting in inaccurate installation of the closing position, and further resulting in a low success rate of power grid closing switching.

[0005] According to one aspect of an embodiment of the present invention, a site selection method for a power grid closing device is provided, comprising: obtaining multiple closing points in a target power grid, and voltage differences and phase angle differences corresponding to the multiple closing points, respectively, wherein the voltage difference is the difference between the voltage values ​​at both ends of the corresponding closing point, and the phase angle difference is the phase difference between the voltages at both ends of the corresponding closing point; based on the voltage differences and phase angle differences corresponding to the multiple closing points, respectively, determining a first set of candidate positions for the closing device from the multiple closing points; based on the equivalent impedances corresponding to the multiple closing points, respectively, determining a second set of candidate positions for the closing device from the multiple closing points; and determining an installation location for the closing device based on the first set of candidate positions and the second set of candidate positions.

[0006] According to another aspect of an embodiment of the present invention, a site selection device for a power grid closing device is further provided, including: an acquisition module for acquiring multiple closing points in a target power grid, and voltage differences and phase angle differences corresponding to the multiple closing points, wherein the voltage difference is the difference between the voltage values ​​at both ends of the corresponding closing point, and the phase angle difference is the phase difference between the voltages at both ends of the corresponding closing point; a first position determination module for determining a first candidate position set of the closing device from the multiple closing points based on the voltage differences and phase angle differences corresponding to the multiple closing points; a second position determination module for determining a second candidate position set of the closing device from the multiple closing points based on the equivalent impedances corresponding to the multiple closing points; and a site selection module for determining the installation position of the closing device based on the first candidate position set and the second candidate position set.

[0007] According to another aspect of an embodiment of the present invention, a non-volatile storage medium is provided, wherein the non-volatile storage medium stores a plurality of instructions, wherein the instructions are suitable for being loaded by a processor and executed by any one of the methods for selecting a site for a power grid loop closure device.

[0008] According to another aspect of an embodiment of the present invention, an electronic device is also provided, comprising one or more processors and a memory, wherein the memory is used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement any one of the methods for site selection of a power grid loop closing device.

[0009] In an embodiment of the present invention, multiple closing points in a target power grid and voltage differences and phase angle differences corresponding to the multiple closing points are obtained, wherein the voltage difference is the difference between the voltage values ​​at both ends of the corresponding closing point, and the phase angle difference is the phase difference between the voltages at both ends of the corresponding closing point; a first candidate position set of a closing device is determined from the multiple closing points based on the voltage differences and phase angle differences corresponding to the multiple closing points; a second candidate position set of the closing device is determined from the multiple closing points based on the equivalent impedances corresponding to the multiple closing points; and an installation position of the closing device is determined based on the first candidate position set and the second candidate position set. This achieves the purpose of constructing two candidate position sets based on the voltage differences, phase angle differences, and equivalent impedances of the multiple closing points, and comprehensively determining the installation position of the closing device based on the two obtained candidate position sets, thereby achieving the technical effect of improving the accuracy of the closing position installation and thereby improving the success rate of power grid closing switching. This solves the technical problem in the related art of inaccurate closing position installation due to incomplete consideration of factors when determining the installation position of the closing device, thereby resulting in a low success rate of power grid closing switching. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0011] Figure 1 is a flow chart of a method for selecting a site for a power grid ring closing device according to an embodiment of the present invention;

[0012] Figure 2 is a schematic diagram of an optional power grid closing point monitoring according to an embodiment of the present invention;

[0013] Figure 3 is another optional schematic diagram of power grid closing point monitoring according to an embodiment of the present invention;

[0014] Figure 4 is a schematic diagram of a curve of an optional closing point voltage difference and phase angle difference according to an embodiment of the present invention;

[0015] Figure 5 1 is a schematic diagram of an optional phase angle difference distribution of a loop closing point according to an embodiment of the present invention;

[0016] Figure 6 is a schematic diagram of an optional impedance distribution according to an embodiment of the present invention;

[0017] Figure 7 2 is a schematic diagram of a site selection device for a power grid ring closing device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0018] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions 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 embodiments described 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 making creative efforts should fall within the scope of protection of the present invention.

[0019] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned 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 an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0020] First, to facilitate understanding of the embodiments of the present invention, some of the terms or nouns involved in the present invention are explained below:

[0021] Bessel's formula, a method used to calculate standard deviation, is used to describe the degree of dispersion of data.

[0022] A flexible closing device is a flexible conductive connection device used to connect a closing ring to a circuit breaker. It usually consists of a flexible copper busbar and a spring connector. It can provide a reliable conductive connection between the closing ring and the circuit breaker and has good flexibility and bending properties.

[0023] Currently, some large regional power grids, due to the limited breaking capacity of the main grid's circuit breakers, disconnect the 220kV busbars. This creates a 500kV ring network as the main grid framework and 220kV ring networks as sub-grids. This ensures that short-circuit currents do not exceed specified limits during faults and that the circuit breakers have the arcing capability to isolate the fault. Each sub-grid typically has three to four 500kV substations and approximately ten 220kV substations. One regional power grid currently has eight sub-grids. During spring and autumn maintenance and prioritizing critical support operations, cross-sub-grid busbar closing operations are common. With the influx of power electronic equipment and renewable energy sources connected to the grid, grid volatility has increased, and distribution network conditions have become increasingly complex. Furthermore, with increasing demands for grid stability, the demand for loop closing and switching operations is increasing.

[0024] In the early days, due to the lack of advanced loop closing technology, loop closing operations mostly used active hard loop closing technology. This technology relies solely on the dispatcher's operating experience and is usually attempted at night when the grid load is small. At the same time, if the loop closing is unsuccessful, the dispatcher will often debug to reduce the loop closing phase angle difference based on personal operating experience. The loop closing efficiency is low and the loop closing control accuracy is poor.

[0025] With the development of high-voltage power electronics technology, flexible interconnected equipment based on power electronics, such as the Unified Power Flow Controller (UPFC), Static Synchronous Compensator (SOP), and Power System Stabilizer (PST), have been proposed. These flexible loop closing devices, installed at the loop closing operation point, adjust the voltage amplitude and phase angle of the busbars at both ends of the loop to achieve soft loop closing technology and mutual flow coordination between the two ends of the loop. These devices require space and are more expensive than other distribution network equipment. Therefore, the installation location of the flexible loop closing device must be accurate. However, the installation requirements of the loop closing device in related technologies are generally determined based on previous fault records and the experience of operators. This incomplete consideration leads to inaccurate loop closing installation, which in turn results in a low success rate of loop closing switching in the power grid.

[0026] In response to the above-mentioned problems, an embodiment of the present invention provides an embodiment of a method for site selection of a power grid loop closing device. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0027] Figure 1 FIG. 1 is a flow chart of a method for selecting a site for a power grid ring closing device according to an embodiment of the present invention. Figure 1 As shown, the method includes the following steps:

[0028] Step S102: Acquire multiple closing points in the target power grid, and voltage differences and phase angle differences corresponding to the multiple closing points, wherein the voltage difference is the difference between the voltage values ​​at both ends of the corresponding closing point, and the phase angle difference is the phase difference between the voltage values ​​at both ends of the corresponding closing point;

[0029] Optionally, the closing point is the power supply switching point between different grid zones in the target power grid. The target power grid may include multiple grid zones, each corresponding to a different substation, line, distribution equipment, etc., and each grid zone can be independently powered. The phase angle difference is the phase difference between the voltages at the closing point, that is, the phase difference between the voltage waveforms at the closing point.

[0030] Optionally, corresponding voltage acquisition terminals can be set at the corresponding positions at both ends of each closing point to collect the voltage U at the two points of the corresponding closing point. a ∠θ a and U b ∠θ b , where Ua and U b are the voltage values ​​at both ends of the corresponding closing point, ∠θ a and ∠θ b They are the voltage phases at both ends of the corresponding closing point, U a -U b That is the voltage difference between the two ends of the corresponding closing point, ∠θ a -∠θ b That is the phase angle difference between the two ends of the corresponding closing point.

[0031] Step S104, determining a first candidate position set of the loop closing device from the multiple loop closing points based on the voltage differences and phase angle differences corresponding to the multiple loop closing points respectively;

[0032] Optionally, the loop closing device may be a flexible loop closing device, which may determine the first candidate position set based on the voltage difference and phase angle difference of multiple loop closing points obtained at a certain moment, or may determine the first candidate position set based on the voltage difference and phase angle difference of multiple loop closing points obtained at each of multiple moments. The voltage difference and phase angle difference across the loop closing point may reflect the voltage stability at both ends of the loop closing point. The greater the voltage difference and / or the greater the phase angle difference, the poorer the stability of the corresponding loop closing point during loop closing and switching. Therefore, the first candidate position set corresponding to the loop closing device may be determined based on the voltage difference and phase angle difference across the loop closing point.

[0033] In an optional embodiment, based on the voltage differences and phase angle differences corresponding to the multiple closing points, a first candidate position set of the closing device is determined from the multiple closing points, including: obtaining the voltage differences and phase angle differences corresponding to the multiple closing points at different times for multiple times to obtain the voltage difference sets corresponding to the multiple closing points, and the phase angle difference sets corresponding to the multiple closing points; judging whether the voltage differences included in the voltage difference sets corresponding to the multiple closing points are within the target voltage difference range, and whether the phase angle differences included in the phase angle difference sets corresponding to the multiple closing points are within the target phase angle difference range, to obtain a judgment result; and determining the first candidate position set from the multiple closing points according to the judgment result.

[0034] Optionally, the larger the voltage difference, the worse the stability of the corresponding closing point during the closing and switching operation; the larger the phase angle difference, the worse the stability of the corresponding closing point during the closing and switching operation. Therefore, when determining the candidate installation positions of the closing device, the positions of the closing points with larger voltage differences and phase angle differences can be selected to form the first candidate position set corresponding to the closing device. Specifically, the target voltage difference range can be set to be greater than a first value, wherein the first value is greater than 0; when the voltage difference across a certain closing point among the multiple closing points is greater than the first value, it is determined that the voltage difference across the closing point is within the target voltage difference range. The target phase angle difference range can be set to be greater than a second value, wherein the second value is an integer greater than 0; when the voltage difference across a certain closing point among the closing points is greater than the second value, it is determined that the phase angle difference across the closing point is within the target phase angle difference range.

[0035] Optionally, when the voltage difference set corresponding to each of the multiple closing points includes the voltage differences obtained at multiple different moments, and the phase difference set includes the phase angle differences obtained at multiple different moments, the average value of the voltage differences in the voltage difference set corresponding to each closing point and the average value of the electrical phase angle differences in the phase angle difference set corresponding to each closing point can be calculated; and whether the average value of the voltage difference of each closing point is within the target voltage difference range and whether the average value of the phase angle difference is within the target phase angle difference range can be determined to determine whether the position of the closing point can be included in the first candidate position set.

[0036] Optionally, when determining the first candidate position set from multiple closing points, set 1 can be formed based on the closing points whose average voltage difference is within the target voltage difference range among the multiple closing points; set 2 can be formed based on the closing points whose average phase angle difference is within the target phase angle difference range among the multiple closing points; according to the average voltage difference and the average phase angle difference, the angles with the highest voltage difference and the largest fluctuation are selected, and the closing points included in set 1 and set 2 are comprehensively sorted. The average value of the sorting position of each closing point in set 1 and set 2 can be calculated to obtain the average sorting position of each closing point in set 1 and set 2, and a predetermined number of closing points with the top average sorting positions are selected; based on the positions of the predetermined number of closing points, the first candidate position set of the closing device is formed.

[0037] Optionally, Set 1 and Set 2 can be determined by determining whether the voltage differences in the voltage difference sets corresponding to the multiple closing points are all within the target voltage difference range, and whether the phase angle differences in the phase angle difference sets corresponding to the multiple closing points are all within the target phase angle difference range. That is, Set 1 is formed based on the closing points in the voltage difference sets corresponding to the multiple closing points whose voltage differences are all within the target voltage difference range; Set 2 is formed based on the closing points in the phase angle difference sets corresponding to the multiple closing points whose phase angle differences are all within the target phase angle difference range. The subsequent processing method is the same as described above and will not be repeated here.

[0038] In an optional embodiment, before determining whether the voltage differences included in the voltage difference sets corresponding to the multiple closing points are within the target voltage difference range, and whether the phase angle differences included in the phase angle difference sets corresponding to the multiple closing points are within the target phase angle difference range, and obtaining the judgment result, the method further includes: determining the average value of the voltage differences included in the voltage difference sets corresponding to the multiple closing points to obtain the average voltage difference; and calculating the average value of the phase angle differences included in the phase angle difference sets corresponding to the multiple closing points to obtain the average phase angle difference; determining the standard deviation of the voltage differences included in the voltage difference sets corresponding to the multiple closing points to obtain the standard voltage difference; and calculating the standard deviation of the phase angle differences included in the phase angle difference sets corresponding to the multiple closing points to obtain the standard phase angle difference; obtaining the target voltage difference range based on the average voltage difference and the standard voltage difference; and obtaining the target phase angle difference range based on the average phase angle difference and the standard phase angle difference.

[0039] Optionally, the target voltage difference range and the target phase angle difference range are determined by calculating the average value and standard deviation of the voltage difference in the voltage difference set corresponding to the multiple closing points (i.e., the average voltage difference and the standard voltage difference), and the average value and standard deviation of the phase angle difference in the phase angle difference set corresponding to the multiple closing points (i.e., the average phase angle difference and the standard phase angle difference). Specifically, the standard voltage difference and the standard phase angle difference (σ) can be calculated based on, but not limited to, the Bessel formula, and the corresponding mean (i.e., the average voltage difference and the standard voltage difference) 3σ range is used as the corresponding target voltage difference range and the target phase angle difference range. Accordingly, when determining Set 1 and Set 2, the closing points within the corresponding mean (i.e., the average voltage difference and the standard voltage difference) 3σ range are found among the multiple closing points to form Set 1 and Set 2.

[0040] It should be noted that after calculating the standard deviation σ based on the Bessel formula, the fluctuation range of the voltage and phase angle of each closing point can be determined using the mean 3σ range. Under normal circumstances, when most closing points perform closing switching operations, the voltage and phase angle fluctuations will not be too large. The voltage difference and phase angle difference of the corresponding closing points will fall within the range of the mean plus or minus 3σ. If some voltage differences and phase angle differences exceed this range, it may indicate that the closing point is abnormal or has abnormal fluctuations. In this way, unstable points during closing switching operations in multiple closing points can be identified in a timely manner to install closing devices so that the closing switching operations can be completed smoothly.

[0041] Step S106, determining a second candidate position set of the loop closing device from the multiple loop closing points based on the equivalent impedances corresponding to the multiple loop closing points;

[0042] Optionally, the equivalent impedances corresponding to the multiple closing points can be obtained by the Thevenin equivalent method based on the impedance values ​​corresponding to the multiple closing points collected at a certain moment. The Thevenin equivalent can be performed on both ends of the closing point in combination with the grid transformer and line grid data under the typical mode of the regional power grid, and the Thevenin equivalent can be performed on both sides of the switch at the corresponding position of the closing point as the port. Using the unit current method, a current of unit 1 is injected at both ends of the closing point i and j, and the admittance matrix of each closing point in the entire regional power grid is as follows:

[0043]

[0044] Since the current is 1, Z is derived from the impedance matrix eq is the equivalent impedance on both sides of the loop closing point, and the calculation formula is as follows: Z eq =Z i +Z j -2Z ij Where U1,…,U a ,…,U b ,…,U n Indicates the voltage at the corresponding closing point; Z i , Z j , Z ij They are the equivalent impedance of the closing point i, the equivalent impedance of the closing point j, and the equivalent mutual impedance between the two ends of the closing point i and j.

[0045] In an optional embodiment, based on the equivalent impedances corresponding to the multiple closing points, a second candidate position set of the loop closing device is determined from the multiple closing points, including: performing cluster analysis based on the equivalent impedances corresponding to the multiple closing points obtained at the target time to obtain clustering results; and determining the second candidate position set based on the clustering results.

[0046] Optionally, the equivalent impedance Z corresponding to the multiple closing points obtained at the target time can be eq Performing cluster analysis, the classification results obtained can show the high and low impedance distribution of multiple closing points, and then quickly and accurately select the closing point positions with large impedance and concentrated impedance distribution, and construct the second candidate position set corresponding to the closing device. The closing points included in the second candidate position set are the closing points corresponding to the high impedance area, that is, the closing points where the total impedance in the corresponding area is greater than the predetermined impedance. It should be noted that a large equivalent impedance indicates that the load at the corresponding closing point position is too large, and there is a greater risk of fluctuations when closing the loop. The candidate installation positions of the closing device selected in the above manner are also more in line with actual operation needs.

[0047] In an optional embodiment, based on the clustering results, a second set of candidate locations is determined, including: determining multiple cluster centers from the clustering results; and obtaining the second set of candidate locations based on the ring points among the multiple ring points that match the multiple cluster centers.

[0048] Optionally, based on the equivalent impedance Z corresponding to multiple closing points eq Perform cluster analysis and create an equivalent impedance distribution map based on the clustering results. This map shows that the impedance distribution exhibits multiple distinct clusters, each corresponding to a different cluster center. From these clusters, the closing points of the high-impedance region are selected to form the second set of candidate locations. For example, if the impedance distribution exhibits two major clusters, the closing points of the high-impedance region are selected to construct the second set of candidate locations.

[0049] Optionally, the target time may be one or more. When there are multiple target time periods, the second candidate position set may be determined based on a combination of multiple cluster analysis results. Specifically, the second candidate position set may be determined based on multiple loop points where the equivalent impedance at multiple time periods is in a high-impedance region.

[0050] In an optional embodiment, before performing cluster analysis based on the equivalent impedances corresponding to multiple closing points obtained at the target time to obtain the clustering results, the method also includes: obtaining the total load power of the target power grid at different times multiple times to obtain the total load power corresponding to multiple different times; and determining the target time from multiple different times based on the total load power corresponding to multiple different times.

[0051] Optionally, the total load power of the target power grid at different moments can reflect the size of the power load of the power grid at the corresponding moment. In order to reduce the impact of the closing-loop switching operation on the power supply, the closing-loop switching operation can be performed during a period when the power load is relatively small. Since the equivalent impedances corresponding to the multiple closing points at the target moment are used to determine the candidate installation positions of the closing device, the power grid operation characteristics at the target moment should match the power grid operation characteristics at the time of closing-loop switching. Therefore, the target moment can be determined based on the total load power of the target power grid at different moments. Specifically, the moment with a smaller total load power and less than a predetermined load threshold among multiple different moments can be selected as the target moment. The second candidate position set is obtained based on the target moment obtained in the above manner, and the result obtained is more in line with the actual closing-loop switching needs of the power grid.

[0052] Step S108: Determine the installation position of the loop closing device based on the first candidate position set and the second candidate position set.

[0053] Optionally, the first candidate location set includes closing points in the target power grid that are prone to large voltage amplitude and phase fluctuations during loop closing and switching, and the second candidate location set includes closing points with large corresponding loads during loop closing and switching. By combining the first and second candidate location sets, closing points with large voltage amplitude and phase fluctuations and large loads during loop closing and switching can be selected as installation locations for the loop closing device. The installation location of the loop closing device obtained on this basis is more accurate and can better ensure the smooth operation of the loop closing and switching operation.

[0054] In an optional embodiment, determining the installation position of the loop closing device based on the first candidate position set and the second candidate position set includes: determining the intersection of the first candidate position set and the second candidate position set; and obtaining the installation position of the loop closing device based on the intersection.

[0055] Optionally, the intersection of the first candidate location set and the second candidate location set can be taken, and a corresponding number of installation locations can be selected from the intersection based on the number of loop closing devices (e.g., 3) to install the loop closing devices. Accordingly, when selecting a corresponding number of installation locations from the intersection based on the number of loop closing devices (e.g., 3), the loop closing points included in the first candidate location set and the second candidate location set can be sorted separately, and the average of the sorted positions of each loop closing point in the first candidate location set and the second candidate location set can be calculated to obtain the average sorted position of each loop closing point. The positions of the corresponding number of loop closing points (i.e., the number of loop closing devices) whose average sorted positions are ranked at the top are determined as the actual installation positions of the loop closing devices. For example, for a certain loop closing point, if it ranks third in the sorted results of the first candidate location set and second in the sorted results of the second candidate location set, then the average sorted position of the loop closing point is 2.5.

[0056] It should be noted that for multiple closing points with the same average ranking position and meeting the required number of closing devices, selection can be performed based on, but not limited to, the principle of prioritizing positions within the first candidate location set or the second candidate location set. For example, if there are three closing devices and there are two closing points ranked third on average, the principle of prioritizing the first candidate location set can be used to determine which of these two closing points has a higher ranking position within the first candidate location set. The closing point with the higher ranking position can then be selected as the installation location for the closing device.

[0057] Through the above steps S102 to S108, it is possible to construct two candidate position sets based on the voltage difference, phase angle difference and equivalent impedance of multiple closing points, and accurately determine the installation position of the closing device based on the two obtained candidate position sets, thereby achieving the technical effect of improving the accuracy of the installation position of the closing position, and then improving the success rate of the closing and switching of the power grid, thereby solving the technical problem in the related art that, when determining the installation position of the closing device, incomplete consideration of factors leads to inaccurate installation of the closing position, and then leads to a low success rate of the closing and switching of the power grid.

[0058] Based on the above embodiment and optional embodiment, the present invention proposes an optional implementation method of a site selection method for a power grid ring closing device, the method comprising:

[0059] S1, select the location where the closing device is to be installed on the target power grid as the closing point, obtain multiple closing points, install a voltage acquisition terminal with real-time vector acquisition function at the selected closing point location, install a voltage acquisition terminal with real-time vector acquisition function on the upstream incoming line at both ends of the bus tie switch required for detection in the main network or distribution network, and collect the vector voltage U with time stamp at both ends of the closing point a ∠θ a and Ub ∠θ b , and the active power P at both ends a and P b , Figure 2 is a schematic diagram of an optional power grid closing point monitoring according to an embodiment of the present invention, Figure 2 The red line in the middle represents the 500kV high voltage grid line, the red circle represents the 500kV grid substation site, the green line represents the 220kV grid line, and the green circle represents the 220kV grid substation site. Figure 2 The two different busbars of the same station with a closed loop station are marked as "Closed Loop Station Busbar 1" and "Closed Loop Station Busbar 2". Figure 2 The letter marks in the figure indicate the identification of each closed-loop station. Figure 3 is another optional schematic diagram of power grid closing point monitoring according to an embodiment of the present invention, Figure 3 Synchronous terminals 1 and 2 can be used as closing point locations. Terminals 1, 2, ..., and n can be used as monitoring devices to perform network-wide synchronous measurement of the closing point locations. The voltage acquisition terminal can be used to collect the voltage across each closing point. The positioning device can be used to determine the location of each closing point. This allows for the positioning of each closing point in the regional power grid and the collection and detection of the voltage across the closing point. The specific implementation process is as follows:

[0060] S11: Select a regional power grid (i.e., a target power grid) with a low loop closing success rate and a need for a loop closing device, and install a power grid real-time data acquisition terminal (i.e., a voltage acquisition terminal) at the corresponding bus tie incoming line (e.g., the installation location of the bus tie switch). This terminal can collect the synchronous vector voltage and active power P with a time stamp.

[0061] S12, before preparing for the loop closing operation, record the voltage vector U at both ends of the loop closing point. a ∠θ a and U b ∠θ b , and record the time stamp t of this moment.

[0062] S13, collect the active power P with time stamp at both ends of all the closed loop points in the power grid area, that is, the active power P of the closed loop sites a and P b , and record the time stamp t of this moment.

[0063] S2, record the voltage at both ends of the loop point and enter it into the historical database. After updating the historical database, the voltage U at both ends of the loop point is recorded. a and U b The voltage difference at both ends of the loop point is obtained by performing a subtraction. At the same time, the phase ∠θ of the voltage at both ends of the loop point is calculated. a and ∠θ bPerform the subtraction to obtain the phase angle difference of the voltage at both ends of the loop closing point. Figure 4 This is a schematic diagram of a curve showing the voltage difference and phase angle difference at a loop closing point according to an embodiment of the present invention. The diagram illustrates the loop closing point, the changes and fluctuations in the voltage difference and phase angle difference across the two ends over time, and uses the 3σ statistical method to perform historical statistical analysis of the voltage and phase angle differences, deriving the range of occurrence of the voltage and phase angle differences in the target power grid and selecting the top 10% of loop closing points with the largest voltage and phase angle differences. The specific implementation process is as follows:

[0064] S21, calculate the difference of the voltage at both ends of the loop point in the regional power grid. a ∠θ a and U b ∠θ b , at the same time T, U a -U b Get the voltage difference of the closing point and perform ∠θ a -∠θ b Get the phase angle difference of the closing point;

[0065] S22, at this moment T, a set of voltage differences and phase angle differences are obtained; at different t1, t2, t3, ..., tn within a period of time, n sets of voltage differences U at different moments in the observation time are obtained. a -U b and phase angle difference ∠θ a -∠θ b , and calculate the arithmetic mean μ, and calculate the standard deviation σ according to the Bessel formula, and find the voltage difference and phase angle difference of the closing point within the range of 3σ of the mean. Taking the phase angle difference as an example, Figure 5 is a schematic diagram of an optional phase angle difference distribution of a loop closing point according to an embodiment of the present invention, Figure 5 The corresponding relationship between the phase angle difference values ​​at multiple sampling moments of a certain closing point within a certain period of time and the probability of occurrence of this value is shown. The horizontal axis represents the phase angle difference value of the closing point, and the vertical axis represents the probability of this value appearing within a certain period of time (such as the period t0-tn). Through the probability calculation method, the mean and standard deviation of the closing phase angle difference within this period of time can be calculated.

[0066] S23, repeating the operations of steps S21 to S22 for all closing points in the regional power grid to obtain the voltage difference and angle difference fluctuation ranges of all closing points in the regional power grid, and selecting a predetermined number of closing point positions with the largest mean values ​​and fluctuation ranges to form a first candidate position set for the closing device.

[0067] S3, based on the historical active power P at both ends of each closing point a and P bBased on the database, the time period when the closing and switching operation needs to be performed is selected, such as the second quarter of a certain year. The Thevenin impedance equivalent calculation is performed on the closing points of the entire network during this period, and an equivalent impedance distribution map is drawn based on the equivalent impedance results of the closing points. Cluster analysis is then performed based on the equivalent impedance distribution map to select the closing points with high impedance values. The specific implementation process is as follows:

[0068] S31, in the power grid area selected in step S2 and at all closing points, select a time t and a closing point under the same time period t1, t2, t3, ..., tn, and then sum the active power of all stations in the power grid area at the same time to obtain the total load P of the regional power grid. grid , and then perform a closed-loop station equivalent impedance solution.

[0069] S32, combined with the grid transformer and line grid data under the typical mode of regional power grid, performs Thevenin equivalence on both ends of the closing point, and performs Thevenin equivalence on both sides of the switch corresponding to the closing point as ports.

[0070] S33, under the regional power grid active power P at this specific time t, calculate the equivalent impedance Z corresponding to the multiple loop points included in the regional power grid eq , based on the equivalent impedance Z corresponding to multiple closing points eq Perform cluster analysis and draw a closed loop equivalent impedance distribution diagram based on the clustering results. Figure 6 is a schematic diagram of an optional impedance distribution according to an embodiment of the present invention;

[0071] S34, through the iso-impedance distribution diagram, it can be seen that the impedance distribution presents two major clustering areas, and the closing point of the high impedance area is selected;

[0072] S35 , the operations from step S31 to step S34 may be repeated, and the loop closing points in the high impedance area of ​​the regional power grid are solved and verified under different t1 , t2 , t3 , … , tn .

[0073] In S4, the voltage difference represents the characteristics of the closing point over time, and the impedance value of the closing point represents the characteristics of the closing point at electrical distance. The intersection of the closing point set calculated from the voltage difference and phase angle difference (i.e., the first candidate location set) and the closing point high impedance value set (i.e., the second candidate location set) is calculated to select the installation location of the closing device. The specific implementation process is as follows:

[0074] S41, through step S2, select set 1 and set 2 based on the voltage difference and phase angle difference of the closing points, repeat the operations of steps S31 to S33, and solve the closing points in the high-impedance area of ​​the regional power grid under different t1, t2, t3, ..., tn, and obtain the closing points in the region where the closing points are located within a specific time according to the angles with the highest average values ​​of the voltage difference and the average values ​​of the phase angle difference and the largest fluctuations, and comprehensively sort the closing points included in set 1 and set 2. The average value of the sorting position of each closing point in set 1 and set 2 can be calculated to obtain the average sorting position of each closing point in set 1 and set 2, and select a predetermined number of closing points with the highest average sorting positions; based on the corresponding positions of the predetermined number of closing points, a first candidate position set of the closing device is formed.

[0075] S42, through step S3, select and solve under different t1, t2, t3, ..., tn, and obtain the probability that the impedance value of the loop closing station in the area appears in the high impedance area within a specific time, and obtain the final location of the loop closing point in the high impedance area to form the second candidate position set of the loop closing device.

[0076] S43: Take the intersection of the first candidate position set and the second candidate position set, and select a corresponding number of installation locations from the intersection based on the number of loop closing devices (e.g., 3), and install the loop closing devices. Accordingly, when selecting a corresponding number of installation locations from the intersection based on the number of loop closing devices (e.g., 3), the loop closing points included in the first candidate position set and the second candidate position set can be sorted separately, and the sorted position of each loop closing point in the first candidate position set and the second candidate position set can be averaged to obtain the average sorted position of each loop closing point. The positions of the corresponding number of loop closing points (i.e., the number of loop closing devices) whose average sorted positions are ranked at the top are determined as the actual installation positions of the loop closing devices. For example, for a certain loop closing point, if it ranks third in the sorted result of the first candidate position set and second in the sorted result of the second candidate position set, then the average sorted position of the loop closing point is 2.5. It should be noted that for multiple closing points with the same average ranking position and meeting the closing device quantity requirement, selection can be performed based on, but not limited to, the principle of prioritizing positions within the first candidate location set or the second candidate location set. For example, if there are three closing devices and two closing points rank third in average ranking, the first candidate location set priority principle can be used to determine which of these two closing points has a higher ranking position within the first candidate location set and select that closing point as the closing point installation location.

[0077] The embodiment can achieve at least one of the following effects: 1) by performing real-time observation, recording and statistical analysis of the voltage difference and vector difference of the closing point, the analysis is performed based on the actual on-site database, and all data are time-stamped, which greatly improves the accuracy compared with manual experience; 2) based on the research results of the closing theory, by calculating the equivalent impedance of the closing point of the entire network in the regional area, the configuration points of the closing device that may need to be installed are analyzed from the perspective of the electrical distance of the power grid; 3) combining the characteristics of the closing point time and the distance characteristics of the power grid, the degree of demand for the closing device at the power grid site can be fully and accurately described, thereby screening the locations where the closing device is most urgently installed.

[0078] This embodiment also provides a site selection device for a power grid ring closure device, which is used to implement the above-mentioned embodiments and preferred implementations. Details already described will not be repeated here. As used below, the terms "module" and "device" may refer to a combination of software and / or hardware that implements a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, implementation using hardware, or a combination of software and hardware, is also possible and contemplated.

[0079] According to an embodiment of the present invention, there is also provided an embodiment of a device for implementing the above-mentioned method for selecting a site for a power grid ring closing device. Figure 7 FIG. 1 is a schematic structural diagram of a site selection device for a power grid ring closing device according to an embodiment of the present invention. Figure 7 As shown, the site selection device for the power grid loop closing device includes: an acquisition module 200, a first position determination module 202, a second position determination module 204, and a site selection module 206, wherein:

[0080] An acquisition module 200 is configured to acquire multiple closing points in a target power grid, as well as voltage differences and phase angle differences corresponding to the multiple closing points, wherein the voltage difference is the difference between the voltage values ​​at both ends of the corresponding closing point, and the phase angle difference is the phase difference between the voltage values ​​at both ends of the corresponding closing point;

[0081] A first position determination module 202 is connected to the acquisition module 200 and is configured to determine a first candidate position set of the loop closing device from the plurality of loop closing points based on the voltage differences and phase angle differences respectively corresponding to the plurality of loop closing points;

[0082] The second position determination module 204 is connected to the first position determination module 202 and is configured to determine a second candidate position set of the loop closing device from the plurality of loop closing points based on equivalent impedances corresponding to the plurality of loop closing points;

[0083] The site selection module 206 is connected to the second position determination module 204 and is configured to determine an installation position of the loop closing device based on the first candidate position set and the second candidate position set.

[0084] In an embodiment of the present invention, an acquisition module 200 is provided to acquire multiple closing points in a target power grid, and voltage differences and phase angle differences corresponding to the multiple closing points, wherein the voltage difference is the difference between the voltage values ​​at both ends of the corresponding closing point, and the phase angle difference is the phase difference between the voltages at both ends of the corresponding closing point; a first position determination module 202 is connected to the acquisition module 200 and is used to determine a first candidate position set of the closing device from the multiple closing points based on the voltage differences and phase angle differences corresponding to the multiple closing points; a second position determination module 204 is connected to the first position determination module 202 and is used to determine a second candidate position set of the closing device from the multiple closing points based on the equivalent impedances corresponding to the multiple closing points. Set; the site selection module 206 is connected to the second position determination module 204, and is used to determine the installation position of the closing device based on the first candidate position set and the second candidate position set, so as to achieve the purpose of constructing two candidate position sets based on the voltage difference, phase angle difference and equivalent impedance of multiple closing points, and accurately determining the installation position of the closing device based on the two obtained candidate position sets, thereby achieving the technical effect of improving the accuracy of the installation position of the closing position, and then improving the success rate of the closing and switching of the power grid, and thus solving the technical problem in the related art that when determining the installation position of the closing device, the factors are not fully considered, resulting in inaccurate installation of the closing position, and then resulting in a low success rate of the closing and switching of the power grid.

[0085] It should be noted that the above modules can be implemented by software or hardware. For example, for the latter, it can be implemented in the following ways: the above modules can be located in the same processor; or the above modules can be located in different processors in any combination.

[0086] It should be noted that the acquisition module 200, first location determination module 202, second location determination module 204, and site selection module 206 correspond to steps S102 to S108 in the embodiment. The examples and application scenarios implemented by these modules and the corresponding steps are the same, but are not limited to the contents disclosed in the above embodiment. It should be noted that these modules, as part of the device, can be run on a computer terminal.

[0087] It should be noted that the optional or preferred implementation of this embodiment can be found in the relevant description in the embodiment, which will not be repeated here.

[0088] The site selection device of the above-mentioned power grid loop closing device may also include a processor and a memory. The above-mentioned acquisition module 200, first position determination module 202, second position determination module 204, site selection module 206, etc. are all stored in the memory as program modules, and the processor executes the above-mentioned program modules stored in the memory to realize the corresponding functions.

[0089] The processor includes a core, which retrieves corresponding program modules from memory. There can be one or more cores. Memory may include non-permanent memory in a computer-readable medium, random access memory (RAM), and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory includes at least one memory chip.

[0090] According to an embodiment of the present application, an embodiment of a non-volatile storage medium is also provided. Optionally, in this embodiment, the non-volatile storage medium includes a stored program, wherein, when the program is executed, the device containing the non-volatile storage medium is controlled to execute any of the above-mentioned methods for selecting a site for a power grid ring closing device.

[0091] Optionally, in this embodiment, the non-volatile storage medium may be located in any computer terminal in a computer terminal group in a computer network, or in any mobile terminal in a mobile terminal group, and the non-volatile storage medium includes a stored program.

[0092] Optionally, when the program is running, the device where the non-volatile storage medium is located is controlled to perform the following functions: obtain multiple closing points in the target power grid, and the voltage differences and phase angle differences corresponding to the multiple closing points, wherein the voltage difference is the difference between the voltage values ​​at both ends of the corresponding closing point, and the phase angle difference is the phase difference between the voltages at both ends of the corresponding closing point; based on the voltage differences and phase angle differences corresponding to the multiple closing points, determine a first candidate position set of the closing device from the multiple closing points; based on the equivalent impedances corresponding to the multiple closing points, determine a second candidate position set of the closing device from the multiple closing points; and determine the installation position of the closing device based on the first candidate position set and the second candidate position set.

[0093] According to an embodiment of the present application, an embodiment of a processor is further provided. Optionally, in this embodiment, the processor is configured to run a program, wherein when the program is run, any one of the above-mentioned methods for selecting a site for a power grid ring closing device is executed.

[0094] According to an embodiment of the present application, an embodiment of a computer program product is also provided. When executed on a data processing device, the program is suitable for executing the steps of the site selection method for initializing any of the above-mentioned power grid loop closing devices.

[0095] Optionally, the above-mentioned computer program product, when executed on a data processing device, is suitable for executing an initialization program having the following method steps: obtaining multiple closing points in the target power grid, and the voltage differences and phase angle differences corresponding to the multiple closing points, wherein the voltage difference is the difference between the voltage values ​​at both ends of the corresponding closing point, and the phase angle difference is the phase difference between the voltages at both ends of the corresponding closing point; based on the voltage differences and phase angle differences corresponding to the multiple closing points, determining a first candidate position set of the closing device from the multiple closing points; based on the equivalent impedances corresponding to the multiple closing points, determining a second candidate position set of the closing device from the multiple closing points; and determining the installation position of the closing device based on the first candidate position set and the second candidate position set.

[0096] An embodiment of the present invention provides an electronic device, which includes a processor, a memory, and a program stored in the memory and executable on the processor. When the processor executes the program, the following steps are implemented: obtaining multiple closing points in a target power grid, and voltage differences and phase angle differences corresponding to the multiple closing points, wherein the voltage difference is the difference between the voltage values ​​at both ends of the corresponding closing point, and the phase angle difference is the phase difference between the voltages at both ends of the corresponding closing point; determining a first candidate position set of a closing device from the multiple closing points based on the voltage differences and phase angle differences corresponding to the multiple closing points; determining a second candidate position set of the closing device from the multiple closing points based on the equivalent impedances corresponding to the multiple closing points; and determining an installation position of the closing device based on the first candidate position set and the second candidate position set.

[0097] The above sequence of the embodiments of the present invention is for description only and does not represent the superiority or inferiority of the embodiments.

[0098] In the above embodiments of the present invention, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0099] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only exemplary. For example, the division of the above modules can be a logical function division. In actual implementation, there may be other division methods, such as multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, modules or indirect coupling or communication connection of modules, which can be electrical or other forms.

[0100] The modules described above as separate components may or may not be physically separate, and the components shown as modules may or may not be physical modules, that is, they may be located in one place or distributed across multiple modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the present embodiment.

[0101] In addition, the functional modules in various embodiments of the present invention may be integrated into a single processing module, or each module may exist physically separately, or two or more modules may be integrated into a single module. The aforementioned integrated modules may be implemented in the form of hardware or software functional modules.

[0102] If the above-mentioned integrated module is implemented in the form of a software functional module and sold or used as an independent product, it can be stored in a computer-readable non-volatile storage medium. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a non-volatile storage medium and includes a number of instructions for enabling a computer device (which can be a personal computer, server or network device, etc.) to execute all or part of the steps of the various embodiments of the present invention. The aforementioned non-volatile storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, magnetic disk or optical disk and other media that can store program code.

[0103] The above are only preferred embodiments of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for selecting a site for a power grid loop closing device, characterized in that: include: Acquire multiple closing points in the target power grid, as well as voltage differences and phase angle differences corresponding to the multiple closing points, wherein the voltage difference is the difference between the voltage values ​​at both ends of the corresponding closing point, and the phase angle difference is the phase difference between the voltages at both ends of the corresponding closing point; Determining a first set of candidate positions of the loop closing device from the multiple loop closing points based on the voltage differences and phase angle differences respectively corresponding to the multiple loop closing points; determining a second candidate position set of the loop closing device from the multiple loop closing points based on equivalent impedances corresponding to the multiple loop closing points; An installation position of the ring closing device is determined based on the first candidate position set and the second candidate position set.

2. The method according to claim 1, characterized in that The determining a first candidate position set of the loop closing device from the multiple loop closing points based on the voltage differences and phase angle differences respectively corresponding to the multiple loop closing points includes: Acquire voltage differences and phase angle differences corresponding to the plurality of closing points at different times for multiple times to obtain a set of voltage differences corresponding to the plurality of closing points and a set of phase angle differences corresponding to the plurality of closing points; Determining whether the voltage differences included in the voltage difference sets corresponding to the plurality of closing points are within a target voltage difference range, and whether the phase angle differences included in the phase angle difference sets corresponding to the plurality of closing points are within a target phase angle difference range, to obtain a determination result; According to the judgment result, the first candidate position set is determined from the multiple closed-loop points.

3. The method according to claim 2, characterized in that Before determining whether the voltage differences included in the voltage difference sets corresponding to the plurality of closing points are within a target voltage difference range, and whether the phase angle differences included in the phase angle difference sets corresponding to the plurality of closing points are within a target phase angle difference range, the method further includes: Determine the average value of the voltage differences included in the voltage difference sets corresponding to the multiple closing points respectively, to obtain an average voltage difference; and calculate the average value of the phase angle differences included in the phase angle difference sets corresponding to the multiple closing points respectively, to obtain an average phase angle difference; Determine the standard deviation of the voltage differences included in the voltage difference sets corresponding to the multiple closing points respectively to obtain a standard voltage difference; and calculate the standard deviation of the phase angle differences included in the phase angle difference sets corresponding to the multiple closing points respectively to obtain a standard phase angle difference; The target voltage difference range is obtained based on the average voltage difference and the standard voltage difference; and the target phase angle difference range is obtained based on the average phase angle difference and the standard phase angle difference.

4. The method according to claim 1, wherein The determining a second candidate position set of the loop closing device from the multiple loop closing points based on the equivalent impedances respectively corresponding to the multiple loop closing points includes: Performing cluster analysis based on the equivalent impedances corresponding to the multiple loop closing points obtained at the target time to obtain a clustering result; Based on the clustering result, the second candidate position set is determined.

5. The method according to claim 4, characterized in that The determining the second candidate position set based on the clustering result includes: determining a plurality of cluster centers from the clustering results; The second candidate position set is obtained based on the ring-closing points among the multiple ring-closing points that match the multiple cluster centers.

6. The method according to claim 4, characterized in that Before performing cluster analysis based on the equivalent impedances corresponding to the multiple loop closing points acquired at the target time to obtain a clustering result, the method further includes: The total load power of the target power grid at different times is obtained multiple times to obtain the total load power corresponding to multiple different times; The target time is determined from the multiple different times based on the total load powers respectively corresponding to the multiple different times.

7. The method according to any one of claims 1 to 6, characterized in that The determining the installation position of the ring closing device based on the first candidate position set and the second candidate position set includes: Determine an intersection of the first candidate position set and the second candidate position set; The installation position of the ring closing device is obtained based on the intersection.

8. A site selection device for a power grid ring closing device, characterized in that: include: An acquisition module is configured to acquire multiple closing points in a target power grid, and voltage differences and phase angle differences corresponding to the multiple closing points, wherein the voltage difference is the difference between the voltage values ​​at both ends of the corresponding closing point, and the phase angle difference is the phase difference between the voltages at both ends of the corresponding closing point; A first position determination module is configured to determine a first candidate position set of the loop closing device from the plurality of loop closing points based on voltage differences and phase angle differences respectively corresponding to the plurality of loop closing points; A second position determination module is configured to determine a second candidate position set of the loop closing device from the plurality of loop closing points based on equivalent impedances corresponding to the plurality of loop closing points; A site selection module is used to determine the installation location of the ring closing device based on the first candidate location set and the second candidate location set.

9. A non-volatile storage medium, characterized in that: The non-volatile storage medium stores a plurality of instructions, and the instructions are suitable for being loaded by a processor and executed by the site selection method for a power grid ring closing device according to any one of claims 1 to 7.

10. An electronic device, characterized in that: The system comprises one or more processors and a memory, wherein the memory is used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement the site selection method for the power grid loop closing device according to any one of claims 1 to 7.

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