Site selection method and device of power grid loop closing device, storage medium and electronic equipment

Abstract

The invention discloses a site selection method and device for a power grid loop closing device, a storage medium and electronic equipment. The method comprises the following steps: acquiring a plurality of loop closing points in a target power grid, and voltage differences and phase angle differences corresponding to the plurality of loop closing points respectively; determining a first candidate position set of the loop closing device from the plurality of loop closing points based on the voltage differences and the phase angle differences corresponding to the plurality of loop closing points; determining a second candidate position set of the loop closing device from the plurality of loop closing points based on the equivalent impedances corresponding to the plurality of loop closing points; and determining the installation position of the loop closing device based on the first candidate position set and the second candidate position set. According to the invention, the technical problem of low power grid loop closing switching success rate caused by inaccurate installation of the loop closing position due to incomplete consideration factors when the installation position of the loop closing device is determined in the prior art is solved.

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 with a voltage level of 220 kilovolts (kV) is disconnected to form a grid partition with a 500kV ring network as the main grid frame and a 220kV ring network 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 pulling an arc. 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 considered are not comprehensive, 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 solution has been proposed yet. 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 position 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 respectively 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 for the closing device from the multiple closing points based on the voltage differences and phase angle differences respectively corresponding to the multiple closing points; determining a second set of candidate positions for the closing device from the multiple closing points based on the equivalent impedances respectively corresponding to the multiple closing points; and determining an installation position 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 also provided, comprising: an acquisition module, used to acquire multiple closing points in a target power grid, and voltage differences and phase angle differences respectively 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, 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 respectively corresponding to the multiple closing points; a second position determination module, used to determine a second candidate position set of the closing device from the multiple closing points based on the equivalent impedances respectively corresponding to the multiple closing points; and a site selection module, used to determine 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 executing any one of the methods for selecting a site for a power grid ring closing device.

[0008] According to another aspect of an embodiment of the present invention, there is further provided an electronic device, 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 closing device.

[0009] In an embodiment of the present invention, by acquiring multiple closing points in a target power grid, and voltage differences and phase angle differences respectively 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 respectively corresponding to the multiple closing points, a first candidate position set of a closing device is determined from the multiple closing points; based on the equivalent impedances respectively 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 first candidate position set and the second candidate position set, an installation position of the closing device is determined, thereby achieving the purpose of constructing two candidate position sets based on the voltage differences, phase angle differences and equivalent impedances of multiple closing points, and comprehensively determining the installation position of the closing device based on the obtained two candidate position sets, thereby achieving the technical effect of improving the accuracy of the closing position installation position, thereby improving the success rate of the closing switch of the power grid, thereby 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, thereby resulting in a low success rate of the closing switch of the power grid. 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 curve diagram of an optional closing point voltage difference and phase angle difference according to an embodiment of the present invention;

[0015] 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;

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

[0017] Figure 7 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 scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0019] It should be noted that the terms "first", "second", etc. in the specification 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 data 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 that are 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 terms or nouns involved in the present invention are explained below:

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

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

[0023] At present, for some large regional power grids, due to the limitation of the breaking capacity of the circuit breaker of the main grid, the busbar of 220kV voltage level is disconnected to form a grid partition with 500kV ring network as the main grid frame and 220kV ring network to ensure that the short-circuit current of the grid does not exceed the standard when a fault occurs, and the circuit breaker has the ability to isolate the fault by arcing. Each grid partition generally has 3 to 4 500kV substations and about 10 220kV substations. There are 8 grid partitions in a certain regional power grid. When the grid mode is changed before the spring and autumn maintenance and important guarantees, the grid will often encounter the operation of closing the busbar between the grid partitions. With the large proportion of power electronic equipment and new energy connected to the grid, the volatility of the grid has become stronger, and the distribution network situation has become more complicated. At the same time, with the higher requirements for grid stability, the demand for closing and switching operations has become higher and higher.

[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 dispatching personnel'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 interconnection equipment based on power electronics technology, such as Unified Power Flow Controller (UPFC), Static Synchronous Compensator (SOP), Power System Stabilizer (PST) and other series of flexible closing devices have been proposed one after another. Such closing devices are installed at the closing operation point, and the voltage amplitude and phase angle of the busbars at both ends of the closing are adjusted to achieve soft closing technology and mutual assistance of current at both ends of the closing. Such devices need to occupy space and are more expensive than other distribution network equipment. Therefore, the installation position of the flexible closing ring needs to be accurate at present. However, the installation requirements of the closing ring device in the relevant technology basically rely on the fault records of previous years and the experience of the operating personnel to determine the installation position of the closing ring device. The factors are not fully considered, resulting in inaccurate installation of the closing ring position, which in turn leads to a low success rate of closing ring switching of the power grid.

[0026] In response to the above problems, an embodiment of the present invention provides a method embodiment for site selection of a power grid 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 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 comprises the following steps:

[0028] Step S102, obtaining 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 voltages at both ends of the corresponding closing point;

[0029] Optionally, the closing point is a power supply switching point between different grid partitions in the target grid. The target grid may include multiple grid partitions, and different grid partitions correspond to different substations, lines, distribution equipment, etc. Multiple grid partitions can be powered separately. The phase angle difference is the phase difference of the voltage at both ends of the closing point, that is, the phase difference between the voltage waveforms at both ends of the closing point.

[0030] Optionally, corresponding voltage collection terminals can be respectively 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 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 It 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 respectively corresponding to the multiple loop closing points;

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

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

[0034] Optionally, the larger the voltage difference, the worse the stability of the corresponding closing point when the closing loop is switched; the larger the phase angle difference, the worse the stability of the corresponding closing point when the closing loop is switched. Therefore, when determining the candidate installation position of the closing device, the position of the closing point where the voltage difference and the phase angle difference are both large 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 between the two ends of a certain closing point among the multiple closing points is greater than the first value, it is determined that the voltage difference between the two ends of 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 between the two ends of a certain closing point among the closing points is greater than the second value, it is determined that the phase angle difference between the two ends of 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 voltage differences obtained at multiple different moments, and the phase difference set includes phase 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 differences in the phase difference set corresponding to each closing point can be calculated; and whether the position of the closing point can be included in the first candidate position set can be determined by 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 difference is within the target phase difference range.

[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; the angles with the highest voltage difference and the largest fluctuation of the phase angle difference are selected according to the average values ​​of the voltage difference and the average values ​​of the phase angle difference, and the closing points included in set 1 and set 2 are comprehensively sorted, and 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, a first candidate position set for the closing device is formed.

[0037] Optionally, the determination of set 1 and set 2 can also be performed by judging 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, the closing points whose voltage differences in the voltage difference sets corresponding to the multiple closing points are all within the target voltage difference range constitute set 1; and the closing points whose phase angle differences in the phase angle difference sets corresponding to the multiple closing points are all within the target phase angle difference range constitute set 2. The subsequent processing method is the same as the above, and will not be repeated here.

[0038] In an optional embodiment, before determining whether the voltage difference included in the voltage difference set corresponding to the multiple closing points is within the target voltage difference range, and whether the phase angle difference included in the phase angle difference set corresponding to the multiple closing points is within the target phase angle difference range, the method further includes: determining the average value of the voltage difference included in the voltage difference set corresponding to the multiple closing points to obtain the average voltage difference; and calculating the average value of the phase angle difference included in the phase angle difference set corresponding to the multiple closing points to obtain the average phase angle difference; determining the standard deviation of the voltage difference included in the voltage difference set corresponding to the multiple closing points to obtain the standard voltage difference; and calculating the standard deviation of the phase angle difference included in the phase angle difference set 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 3σ range of the corresponding mean (i.e., the average voltage difference and the standard voltage difference) in the multiple closing points are found 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 are performing closing switching operations, the voltage and phase angle fluctuations will not be too large, and 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 fluctuates abnormally. In the above manner, the unstable points during the closing switching operation in multiple closing points can be identified in time to install the closing device so that the closing switching operation 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 respectively corresponding to the multiple loop closing points;

[0042] Optionally, the equivalent impedances corresponding to multiple closing points can be obtained through 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 in a typical 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 ports. 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 respectively 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 closing device is determined from the multiple closing points, including: performing cluster analysis based on the equivalent impedances corresponding to the multiple closing points acquired 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 each of the multiple loop closing points obtained at the target time can be eq Cluster analysis is performed, and the classification results obtained can present the high and low impedance distribution of multiple closing points, and then the closing point positions with large impedance and concentrated impedance distribution can be quickly and accurately selected to 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 the closing switch is turned on. The candidate installation positions for 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, determining a second set of candidate positions includes: determining multiple cluster centers from the clustering results; and obtaining the second set of candidate positions 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 draw an equivalent impedance distribution map based on the clustering results; through the equivalent impedance distribution map, it can be seen that the impedance distribution presents multiple different clustering areas, and different clustering areas correspond to different clustering centers. The closing points of the high impedance area are selected from multiple different clustering areas to form the second candidate position set. For example, when the impedance distribution presents two major clustering areas, the closing points of the high impedance area are selected to construct the second candidate position set.

[0049] Optionally, the target time may be one or more, and when there are multiple target times, the second candidate position set may be determined based on multiple cluster analysis results. Specifically, the second candidate position set may be determined based on multiple closing points where the equivalent impedances at multiple times are in the 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 for multiple times to obtain the total load power corresponding to multiple different times; based on the total load power corresponding to multiple different times, determining the target time from multiple different times.

[0051] Optionally, the total load power of the target power grid at different times can reflect the size of the power load of the power grid at the corresponding time. 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 of relatively small power load. Since the equivalent impedances corresponding to the multiple closing points at the target time are used to determine the candidate installation positions of the closing device, the power grid operation characteristics at the target time should match the power grid operation characteristics during the closing-loop switching. Therefore, the target time can be determined based on the total load power of the target power grid at different times. Specifically, the time when the corresponding total load power is small and less than the predetermined load threshold value among multiple different times can be selected as the target time. The second candidate position set is obtained based on the target time 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: determining 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 position set includes closing points in the target power grid that are prone to large voltage amplitude and phase fluctuations during closing switching, and the second candidate position set includes closing points with large corresponding loads during closing switching. By combining the first candidate position set and the second candidate position set, closing points with large voltage amplitude and phase fluctuations and large loads during closing switching can be screened out as installation positions for closing devices. The installation position of the closing device obtained on this basis is more accurate and can better ensure the smooth closing 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 position set and the second candidate position set can be taken, and a corresponding number of installation positions can be selected from the intersection according to the number of closing devices (such as 3), and the closing devices can be installed. Correspondingly, when a corresponding number of installation positions are selected from the intersection according to the number of closing devices (such as 3), the closing points included in the first candidate position set and the second candidate position set can be sorted respectively, and the sorted positions of each closing point in the first candidate position set and the second candidate position set are averaged to obtain the average sorted position of each closing point, and the positions of the closing points of the corresponding number (i.e., the number of closing devices) whose average sorted positions are ranked in the front are determined as the actual installation positions of the closing devices. For example, for a certain closing point, the closing point ranks third in the sorted results of the first candidate position set and ranks second in the sorted results of the second candidate position set, then the average sorted position of the closing point is 2.5.

[0056] It should be noted that, for multiple closing points with the same average ranking position and meeting the number requirement of closing devices, they can be screened according to, but not limited to, the principle of priority in the first candidate position set or the position priority in the second candidate position set. For example, when there are three closing devices, there are two closing points with the third place in the average ranking position. At this time, according to the principle of priority in the first candidate position set, it can be determined which of the two closing points has a higher ranking position in the first candidate position set, and the closing point with a higher ranking position can be selected as the installation position of 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 technology 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.

[0058] Based on the above embodiments and optional embodiments, the present invention proposes an implementation method of an optional 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, install a voltage acquisition terminal with real-time vector acquisition function on the upper incoming line at both ends of the bus tie switch required to be detected 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 buses of the same station are marked as "Bus 1 of the closed-loop station" and "Bus 2 of the closed-loop station". 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 The synchronization terminal 1 and the synchronization terminal 2 can be used as the closing point location. The terminal 1, terminal 2...terminal n are used as monitoring equipment to perform the whole network synchronous measurement of the closing point location. The voltage at both ends of each closing point is collected through the voltage collection terminal. The location of each closing point is determined by the positioning device, thereby realizing the positioning of each closing point in the regional power grid and the collection and detection of the voltage at both ends of the closing point. The specific implementation process is as follows:

[0060] S11, select a regional power grid (i.e., target power grid) in which the closing success rate is low and a closing device is needed, and install a power grid real-time data acquisition terminal (i.e., voltage acquisition terminal) at the corresponding bus tie incoming line (such as the installation position of the bus tie switch), which can collect synchronous vector voltage and active power P with time stamp;

[0061] S12, before preparing for the closing operation, the voltage vector U is recorded at both ends of the 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 closing point and enter it into the historical database. After updating the historical database, the voltage U at both ends of the closing point is recorded. a and U b The voltage difference between the two ends of the closing point is obtained by subtracting the voltage between the two ends of the closing point. At the same time, the phase ∠θ of the voltage between the two ends of the closing 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 curve diagram of an optional closing point voltage difference and phase angle difference according to an embodiment of the present invention, which shows the closing point; the change and fluctuation of the voltage difference and phase angle difference at both ends over time; and uses the 3σ statistical method to perform historical statistical analysis of the voltage difference and phase angle difference, obtain the range statistics of the voltage difference and phase angle difference of the target power grid, and select the top 10% of the closing points with larger voltage difference and phase angle difference. 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, and the voltage U 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 difference and phase angle difference is obtained; at different t1, t2, t3, ..., tn within a period of time, n sets of voltage difference U at different moments in the observation time are obtained a -U b and phase angle difference ∠θ a -∠θ b , and find 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 ​​of a certain closing point at multiple sampling moments within a certain period of time and the probability of occurrence of the 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 in a certain period of time (such as the t0-tn period). 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 step S21 to step S22 for all the closing points in the regional power grid, obtaining the voltage difference and angle difference fluctuation range of all the closing points in the regional power grid, and selecting a predetermined number of closing point positions with the largest mean value and fluctuation range to form a first candidate position set of the closing device.

[0067] S3, based on the historical active power P at both ends of each closing point a and P bDatabases such as the Grid Database and the Grid Database are used to select the time period when the closing operation needs to be performed, 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 time period, and an equivalent impedance distribution map is drawn based on the equivalent impedance results of the closing points. Cluster analysis is 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 the closing points, a time t and a closing point are selected under the same time period t1, t2, t3, ..., tn, and then the active power of all stations in the power grid area at the same time is summed 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 at the corresponding position of 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 equivalent 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 closing points in the high impedance area of ​​the regional power grid are solved and verified under different t1, t2, t3, ..., tn.

[0073] S4, the voltage difference represents the characteristics of the closing point in the historical time, and the impedance value of the closing point represents the characteristics of the closing point in the electrical distance. The closing point set (i.e., the first candidate position set) and the closing point high impedance value set (i.e., the second candidate position set) calculated by the voltage difference and phase angle difference are intersected to select the installation position 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 step S31 to step 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 included in set 1 and set 2 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 fluctuation within a specific time. 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 top 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 constructed.

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

[0076] S43, take the intersection of the first candidate position set and the second candidate position set, and select the corresponding number of installation positions from the intersection according to the number of closing devices (such as 3), and install the closing devices. Correspondingly, when selecting the corresponding number of installation positions from the intersection according to the number of closing devices (such as 3), the closing points included in the first candidate position set and the second candidate position set can be sorted respectively, and the sorted positions of each closing point in the first candidate position set and the second candidate position set are averaged to obtain the average sorted position of each closing point, and the positions of the closing points of the corresponding number (i.e., the number of closing devices) whose average sorted positions are ranked in the front are determined as the actual installation positions of the closing devices. For example, for a certain closing point, the closing point ranks third in the sorted result of the first candidate position set and ranks second in the sorted result of the second candidate position set, then the average sorted position of the closing point is 2.5. It should be noted that for multiple closing points with the same average ranking position and meeting the number requirement of closing devices, they can be screened according to, but not limited to, the principle of priority in the first candidate position set or the position priority in the second candidate position set. For example, when there are three closing devices, there are two closing points with the third place in the average ranking position. At this time, according to the principle of priority in the first candidate position set, which of the two closing points has a higher ranking position in the first candidate position set can be selected as the closing point installation position.

[0077] The embodiments can achieve at least one of the following effects: 1) Real-time observation, recording and statistical analysis of voltage difference and vector difference of the closing point are performed, and the analysis is performed based on the actual on-site database. At the same time, all data are marked with time, which greatly improves the accuracy compared with manual experience; 2) Based on the research results of closing point theory, the equivalent impedance of the closing point is calculated for the entire network in the regional area, and 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 power grid distance characteristics, the degree of demand for the closing device at the power grid site can be fully and accurately described, thereby screening out the most urgent installation locations of the closing device.

[0078] In this embodiment, a site selection device for a power grid ring closing device is also provided, and the device is used to implement the above-mentioned embodiments and preferred implementation modes, and the descriptions that have been made will not be repeated. As used below, the terms "module" and "device" can be 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, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0079] According to an embodiment of the present invention, there is also provided an embodiment of a device for implementing the site selection method of the above-mentioned power grid ring closing device. Figure 7 is a structural schematic diagram of a site selection device for a power grid ring closing device according to an embodiment of the present invention, such as Figure 7 As shown, the site selection device of the above-mentioned power grid ring 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] The acquisition module 200 is used to 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 voltages at both ends of the corresponding closing point;

[0081] A first position determination module 202, connected to the acquisition module 200, is used to determine 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;

[0082] The 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 loop closing device from the multiple loop closing points based on the equivalent impedances respectively corresponding to the multiple loop closing points;

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

[0084] In the embodiment of the present invention, an acquisition module 200 is provided to acquire multiple closing points in the target power grid, and voltage differences and phase angle differences respectively 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 respectively 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 respectively 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 switch of the power grid, and then solving the technical problem in the related technology 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 switch 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, the first location determination module 202, the second location determination module 204, and the site selection module 206 correspond to steps S102 to S108 in the embodiment, and the examples and application scenarios implemented by the modules and the corresponding steps are the same, but are not limited to the contents disclosed in the above embodiments. It should be noted that the modules as part of the device can be run in a computer terminal.

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

[0088] The site selection device of the above-mentioned power grid closing device may also include a processor and a memory. The above-mentioned acquisition module 200, the first position determination module 202, the second position determination module 204, the 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 kernel, which retrieves the corresponding program module from the memory. The kernel may be one or more. The 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. The 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 where the non-volatile storage medium is located is controlled to execute any one 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 also provided. Optionally, in this embodiment, the processor is used 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 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 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 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 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 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 respectively 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 respectively 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 respectively 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 emphasis. 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 schematic. For example, the division of the above modules can be a logical function division. There may be other division methods in actual implementation, 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 separated, and the components shown as modules may or may not be physical modules, that is, they may be located in one place or distributed on 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, each functional module in each embodiment of the present invention may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of software functional modules.

[0102] If the above-mentioned integrated module is implemented in the form of a software function 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, including a number of instructions to enable a computer device (which can be a personal computer, server or network device, etc.) to perform 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 codes.

[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 closing device, characterized in that: include: Acquire multiple closing points in the target power grid, and voltage differences and phase angle differences respectively 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; Determine 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; Based on the equivalent impedances respectively corresponding to the multiple closing points, determining a second candidate position set of the closing device from the multiple closing points; An installation position of the loop 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 respectively corresponding to the multiple closing points at different times for multiple times to obtain voltage difference sets respectively corresponding to the multiple closing points and phase angle difference sets respectively corresponding to the multiple closing points; Determine whether the voltage differences included in the voltage difference sets respectively 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 respectively corresponding to the plurality of closing points are within a target phase angle difference range, and obtain a determination result; According to the judgment result, the first candidate position set is determined from the multiple loop points.

3. The method according to claim 2, characterized in that Before determining whether the voltage difference included in the voltage difference sets respectively corresponding to the multiple closing points is within the target voltage difference range, and whether the phase angle difference included in the phase angle difference sets respectively corresponding to the multiple closing points is within the 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 difference 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 difference 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, characterized in that 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 equivalent impedances corresponding to the multiple loop closing points respectively 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 loop points among the multiple loop 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 respectively corresponding to the multiple loop closing points acquired at the target time to obtain a cluster 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 closing device, characterized in that: include: An acquisition module is used to acquire multiple closing points in the target power grid, and voltage differences and phase angle differences respectively 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, 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, configured to determine a second candidate position set of the loop closing device from the plurality of loop closing points based on equivalent impedances respectively 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 as described in any one of claims 1 to 7.

10. An electronic device, characterized in that: It includes 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 closing device as described in any one of claims 1 to 7.

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