Power distribution network dispatching control method based on special variable acquisition terminal

Abstract

The application belongs to the technical field of distribution network dispatching control, and specifically discloses a distribution network dispatching control method based on a distribution transformer acquisition terminal, which comprises the following steps: synchronously acquiring the current and voltage of multiple lines, performing consistency checking on branch current and total current and consistency checking on voltage drop of adjacent lines based on upstream and downstream and parallel relationship, and correcting the electric parameters according to the checking result; comparing the corrected electric parameters with the out-of-limit threshold, locating the dispatching demand line and evaluating the dispatching demand; searching for candidate lines, calculating the remaining carrying capacity and checking the voltage thermal stability, sorting and accumulating the qualified candidate lines according to the remaining carrying capacity, screening the dispatching line to perform load transfer; rechecking the electric parameters after a delay duration, marking the line as unusable and returning to the correction step if the dispatching target is not met, and alarming if the maximum number of cycles is exceeded. The application improves the accuracy and reliability of distribution network dispatching through spatial coordination correction and closed-loop review.

Description

Technical Field

[0001] This invention belongs to the field of power distribution network dispatch and control technology, and relates to a power distribution network dispatch and control method based on a dedicated transformer acquisition terminal. Background Technology

[0002] Dedicated transformer data acquisition terminals are used to collect electrical parameters such as current and voltage from various lines on the user side, enabling power consumption monitoring and load control. During distribution network operation, anomalies such as current or voltage exceeding limits may occur. Traditional methods rely on manual handling by maintenance personnel, resulting in slow response and excessive dependence on experience. Some existing intelligent distribution systems attempt to automatically search for available power transfer lines and execute scheduling based on collected parameters to improve power supply reliability.

[0003] For example, Chinese invention patent CN115714382A discloses a method and apparatus for real-time dispatching of an active distribution network based on security reinforcement learning. The method includes: establishing a real-time dispatching model for an active distribution network containing distributed generation resources; transforming the model into a constrained Markov decision process model; training the constrained Markov decision process model using a reinforcement learning algorithm to obtain a policy neural network; and using the policy neural network to output the optimal real-time dispatching strategy to achieve real-time dispatching of the active distribution network. This solution can balance economy and security even in the absence of an accurate model.

[0004] However, the above-mentioned existing technologies have the following shortcomings: First, the method uses the collected data for reinforcement learning decision-making, but does not perform consistency verification and correction on the measured current and measured voltage of multiple lines collected by the special transformer acquisition terminal. As a result, when there are deviations in the measured data, it cannot identify and correct the deviated lines, which leads to misjudgment of the scheduling strategy based on erroneous data and inaccurate location of abnormal lines.

[0005] Second, although the method performs safety constraint verification before scheduling actions are executed through action monitors and action correctors, it does not set up a delayed review step after scheduling execution. When the load transfer operation is completed, if the current of the scheduling demand line still exceeds the over-limit threshold or the voltage has not returned to the normal range, the scheduling parameters cannot be dynamically adjusted or the scheduling operation can be rolled back based on the review results. This makes it difficult to ensure the reliable achievement of the scheduling objective and poses a risk that scheduling failures cannot be automatically recovered. Summary of the Invention

[0006] In view of this, in order to solve the problems mentioned in the background technology, a distribution network dispatch and control method based on dedicated transformer acquisition terminal is proposed.

[0007] The objective of this invention can be achieved through the following technical solution: This invention provides a distribution network dispatch and control method based on a dedicated transformer acquisition terminal, comprising: synchronously acquiring the measured current and measured voltage of multiple lines through the dedicated transformer acquisition terminal; based on the upstream and downstream connection relationship and adjacent parallel relationship of the lines, performing consistency verification on the measured current of each downstream branch line and the measured current of the upstream total line, and performing consistency verification on the measured voltage drop of adjacent lines, and obtaining the corrected electrical parameters based on the verification results.

[0008] The corrected electrical parameters are compared with the preset over-limit thresholds to locate the lines with scheduling needs and evaluate their scheduling requirements.

[0009] Based on the distribution network connection relationship, candidate lines for electrical connection of the dispatching line are searched and the remaining carrying capacity of the candidate lines is calculated. The voltage thermal stability of the candidate lines is checked and dispatching lines are selected accordingly, and load transfer is performed.

[0010] After a preset delay, the electrical parameters of the required and scheduled lines are checked to determine whether the scheduling objective is met. If the scheduling objective is met, the current scheduling ends; otherwise, based on the checked electrical parameters, the process returns to the electrical parameter acquisition and spatial collaborative correction steps.

[0011] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The present invention performs consistency verification of branch current and total current based on upstream and downstream and adjacent relationships by measuring the current and voltage of multiple lines, and performs consistency verification of voltage drop of adjacent lines. The electrical parameters are corrected according to the verification results. When there is a deviation in the measured data, the deviation line can be identified and corrected, avoiding scheduling misjudgment based on erroneous data, and improving the accuracy of abnormal line location.

[0012] (2) This invention re-checks and collects the scheduling demand line and the scheduling line after the scheduling operation is completed and after a preset delay time. The re-checked electrical parameters are compared with the corrected electrical parameters to determine whether the scheduling target is met. If not, the scheduling target is dynamically adjusted or rolled back and returned to the correction step, which ensures the reliable realization of the scheduling target and avoids the risk of not being able to recover automatically after scheduling failure.

[0013] (3) By comparing the corrected electrical parameters with the over-limit threshold, the present invention identifies the line with over-limit current or over-limit current and all the electrically connected lines downstream of its upstream branch nodes as the set of lines with scheduling demand, and on this basis evaluates the load transfer demand and voltage support demand, thus realizing the systematic identification of the range of lines electrically associated with the over-limit line.

[0014] (4) This invention searches for and schedules candidate lines that are electrically connected to the required lines, calculates their remaining capacity and checks the voltage thermal stability, sorts the qualified candidate lines according to their remaining capacity and adds them up in sequence, selects the scheduling lines that can jointly carry all the current to be transferred, and allocates the transfer current according to the proportion of the remaining capacity. Under the premise of ensuring voltage thermal stability, the load transfer is completed, avoiding the risk of scheduling failure due to insufficient capacity of a single line, and improving the reliability of the scheduling scheme. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram showing the connections between the steps of the method of the present invention;

[0017] Figure 2 This is a schematic diagram showing the connection steps of the current consistency verification and correction process in this invention;

[0018] Figure 3 This is a schematic diagram of the voltage drop consistency verification and correction steps of the present invention. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] This invention synchronously collects measured current and voltage data from multiple power lines via a dedicated transformer acquisition terminal. Based on upstream and downstream relationships and adjacent lines, it performs consistency checks on branch currents and total currents, as well as voltage drops on adjacent lines, and corrects electrical parameters according to the check results. Then, it uses the corrected electrical parameters to locate abnormal lines and assess dispatching needs. By searching for candidate lines, calculating capacity, and verifying voltage thermal stability, it selects dispatching lines to execute load transfer. Finally, through preset delay review and closed-loop correction, it achieves precise control and adaptive adjustment of the distribution network dispatching, solving the problems of misjudgment due to data deviation and the inability to automatically recover from dispatching failures caused by the lack of closed-loop review in existing technologies.

[0021] Please see Figure 1As shown, the power distribution network dispatch and control method based on a dedicated transformer acquisition terminal provided by the present invention includes the following steps S1 to S4.

[0022] S1, Electrical Parameter Acquisition and Spatial Coordinated Correction

[0023] The measured current and voltage of multiple lines are simultaneously collected by a dedicated transformer acquisition terminal. Based on the upstream and downstream connection relationships and adjacent parallel relationships of the lines, the consistency of the measured current of each downstream branch line with the measured current of the upstream total line is verified, as well as the consistency of the measured voltage drop of adjacent lines. Corrected electrical parameters are obtained based on the verification results. Adjacent lines refer to two lines with a common electrical connection node, including lines connected end-to-end to form an upstream and downstream power supply path, and parallel branch lines derived from the same branch node. Voltage drop refers to the difference between the measured voltage at the beginning and end of an adjacent line.

[0024] Please see Figure 2 As shown, exemplarily, the consistency verification of the measured current of each downstream branch line with the measured current of the upstream main line includes the following steps S1-1 to S1-5.

[0025] S1-1. Obtain the measured current of upstream and downstream lines: Obtain the measured current of the upstream main line and each downstream branch line collected by the same dedicated transformer acquisition terminal.

[0026] S1-2. Calculate the current and residual and determine the deviation: Sum the measured currents of each downstream branch line and calculate the residual between the downstream branch line current and the measured current of the upstream total line. If the residual exceeds the preset threshold, it is determined that there is a current deviation.

[0027] It should be added that the preset threshold is used to determine whether the residual between the sum of the downstream branch currents and the upstream total current exceeds the allowable range of normal measurement error. This preset threshold can be determined comprehensively based on the current measurement accuracy of the dedicated transformer acquisition terminal (e.g., 2 to 3 times the nominal error of the instrument) and a preset percentage of the line's rated current (e.g., 1% to 5%). As a specific implementation, it can be directly set to 2% of the rated current based on engineering experience.

[0028] S1-3. Screening of lines to be corrected: After determining that there is a current deviation, calculate the deviation rate between the measured current and the historical average value of each downstream branch line, and select the branch lines with a deviation rate greater than the preset lower limit of the deviation rate as the lines to be corrected.

[0029] It should be added that the preset deviation rate lower limit is used to distinguish between normal historical fluctuations and abnormal deviations in line current. This lower limit value can be set according to the standard deviation multiple of the historical current data of each downstream branch line. As a specific implementation method, for each branch line, the current values ​​of at least the most recent thirty historical collection points are statistically analyzed, the average value and standard deviation are calculated, and the preset deviation rate lower limit is set to twice the standard deviation divided by the historical average value and then multiplied by 100%. If the relative magnitude of the measured current of a certain line deviating from the historical average value exceeds this value, it is considered that there may be an abnormal deviation and it needs to be listed as a line to be corrected.

[0030] S1-4. Calculate the total correction current: Calculate the difference between the measured current of the upstream total line and the sum of the measured currents of all non-corrected lines, and use it as the total correction current.

[0031] S1-5. Proportional allocation of correction current: Calculate the sum of the measured current values ​​of all lines to be corrected as the total measured current of the lines to be corrected, and divide the measured current value of each line to be corrected by the total measured current of the lines to be corrected to obtain the allocation ratio of each line to be corrected. Then multiply the total correction current by the allocation ratio to obtain the correction current of each line to be corrected.

[0032] Please see Figure 3 As shown, exemplarily, the consistency verification of voltage drop across adjacent lines includes the following steps S1-6 to S1-9.

[0033] S1-6. Calculate the measured voltage drop and theoretical voltage drop: Obtain the measured voltage at the beginning and end of the adjacent line, take the difference between the measured voltage at the beginning and the measured voltage at the end as the measured voltage drop, and calculate the theoretical voltage drop based on the line impedance parameters and the measured current flowing through the line.

[0034] S1-7. Deviation Comparison and Marking of Abnormal Lines: Compare the measured voltage drop with the theoretical voltage drop, calculate the deviation, and if the deviation exceeds the preset voltage deviation threshold, determine that the corresponding line has a voltage abnormality and mark the line as a line whose voltage needs to be corrected.

[0035] It should be added that the preset voltage deviation threshold is used to determine whether the deviation between the measured voltage drop and the theoretical value exceeds the normal allowable range. In a specific embodiment, a sequence of deviations between the measured and theoretical voltage drops is obtained during a continuous historical period when the line is operating normally and has no record of exceeding limits. The standard deviation of this sequence is calculated, and the preset voltage deviation threshold is set to three times the standard deviation. The continuous historical period can be a time window consisting of at least thirty recent sampling points.

[0036] S1-8. Determine adjacent healthy lines: Traverse all adjacent lines, collect the set of all lines marked as voltage to be corrected, and take the adjacent lines not marked as voltage to be corrected as adjacent healthy lines.

[0037] S1-9. Calculate the corrected voltage: For each line whose voltage needs to be corrected, the corrected voltage of the line whose voltage needs to be corrected is calculated by interpolation, with reference to the voltage drop coefficient of the adjacent healthy line.

[0038] Specifically, the calculation of the correction voltage includes the following steps:

[0039] S1-9-1, Constructing a Reference Dataset

[0040] A reference set of all adjacent healthy lines that share the same upstream or downstream node as the line to be corrected and were not marked as having voltage anomalies in the aforementioned consistency check is obtained. If the measured current of an adjacent healthy line is zero, that line is removed from the reference set.

[0041] For each healthy line in the reference set, calculate its voltage drop factor. The specific calculation method is as follows: subtract the measured voltage at the end of the healthy line from the measured voltage at the beginning of the healthy line, and divide the difference by the measured current flowing through the healthy line.

[0042] S1-9-2, Determine the interpolation variables

[0043] With line impedance as the independent variable and voltage drop factor as the dependent variable, the impedance value of the line to be corrected is denoted as the line impedance to be corrected.

[0044] S1-9-3. Estimating the voltage drop coefficient of the line to be corrected using linear interpolation.

[0045] Based on the number of healthy lines in the reference set, the following three cases are handled: If the reference set contains two or more healthy lines: Select the two healthy lines whose impedance values ​​are closest to the impedance of the line to be corrected from the reference set, denoted as the first healthy line (impedance value less than or equal to the impedance of the line to be corrected) and the second healthy line (impedance value greater than or equal to the impedance of the line to be corrected). Calculate the estimated voltage drop factor of the line to be corrected based on the linear interpolation formula. , ,in , Voltage drop coefficients for the first and second healthy circuits, respectively. The impedance of the line to be corrected. , These are the impedances of the first and second healthy circuits, respectively.

[0046] The reference set contains only one healthy line: calculate the estimated voltage drop factor for the line to be corrected. , ,in This represents the voltage drop factor for the healthy circuit. Its impedance.

[0047] If the reference set is empty: divide the difference between the measured voltage at the beginning of the line to be corrected and 95% of the rated voltage by the measured current of the line. Here, 95% of the rated voltage is used as the lower limit reference value of the voltage at the end of the line, that is, it is assumed that the voltage at the end of the line is not lower than 95% of the rated voltage within the allowable range of dispatch.

[0048] S1-9-4, Calculate the correction voltage

[0049] Multiply the estimated voltage drop factor of the line to be corrected by the measured current of the line to obtain the estimated voltage drop of the line. Then subtract the estimated voltage drop from the measured voltage at the beginning of the line to be corrected to obtain the corrected voltage at the end node of the line.

[0050] For example, obtaining the corrected electrical parameters includes: for a branch line that has undergone current correction, using the corrected current as the corrected current of the line; otherwise, using the measured current as the corrected current of the line.

[0051] For lines that have undergone voltage correction, the corrected voltage is used as the corrected voltage for that line; otherwise, the measured voltage is used as the corrected voltage for that line.

[0052] The corrected current and corrected voltage are used together as the corrected electrical parameters.

[0053] S2. Abnormal route location and scheduling requirement assessment

[0054] The corrected electrical parameters are compared with the preset over-limit thresholds to locate the lines with scheduling needs and evaluate their scheduling requirements.

[0055] For example, the location scheduling demand line includes: comparing the corrected current of each line with a preset current over-limit threshold; if the current exceeds the threshold, the line is marked as a current over-limit line.

[0056] It should be added that the preset current over-limit threshold is used to determine whether the line current exceeds the allowable range for normal operation. In this embodiment, the threshold is obtained by the following statistical method: obtaining a sequence of measured current values ​​of the line during a continuous historical period when it is operating normally and has no over-limit records, and then taking the maximum value in the historical sequence as the preset current over-limit threshold.

[0057] The corrected voltage of each line is compared with the preset voltage threshold range. If the voltage is lower than the lower threshold or higher than the upper threshold, the line is marked as a voltage over-limit line.

[0058] It should be added that the preset voltage threshold range is used to determine whether the line voltage is within the allowable range for normal operation, including a lower threshold and an upper threshold. The lower threshold is used to determine if the voltage is too low, and the upper threshold is used to determine if the voltage is too high. The preset voltage threshold range is obtained through the following statistical method: obtaining a sequence of measured voltage values ​​for the line during a continuous historical period of normal operation without any record of exceeding limits, and calculating the minimum and maximum values ​​of this sequence, which are used as the lower threshold and upper threshold, respectively.

[0059] Lines marked as exceeding current or voltage limits will be used as the initial dispatching demand lines.

[0060] Based on the distribution network topology, trace the upstream adjacent branch nodes that are directly electrically connected to the initial dispatch demand line, and take all lines located downstream of the branch node and electrically connected to the initial dispatch demand line as dispatch demand lines.

[0061] It should be noted that all lines downstream of this branch node are considered as dispatch demand lines because, in the tree topology of the distribution network, downstream lines supplied by the same upstream branch node are electrically coupled, sharing the voltage level and short-circuit capacity constraints of that branch node, and are all electrically connected to the initial dispatch demand lines. When one of these lines is marked as an initial dispatch demand line due to overload or voltage exceeding limits, other downstream lines supplied by that branch node also face potential safety risks. On the one hand, if the upstream branch node itself has insufficient capacity or voltage drop issues, all downstream lines within its power supply range will be affected; on the other hand, during subsequent load transfer scheduling, if only the initially exceeding-limit line is processed while other lines under the same node are ignored, lines that were originally not exceeding limits may develop new exceeding limits due to accepting transferred loads or adjustments to their operating modes. Therefore, it is necessary to include all lines downstream of this branch node in the dispatch demand line set to ensure the completeness and effectiveness of scheduling decisions.

[0062] For example, the assessment of the scheduling demand of the lines includes: first, for lines in the scheduling demand that do not have a current over-limit marker and do not have a voltage over-limit marker (i.e., healthy lines included because they share an upstream branch node with over-limit lines), their scheduling demand is marked as no demand, and no effective demand is generated in the subsequent load transfer or voltage support calculation.

[0063] If a line with a scheduling requirement has a current limit violation flag, it is determined that the line has a load transfer requirement. The current limit violation amount of the line is calculated as the current to be transferred, and the access node of the line is used as the scheduling source point. The current limit violation amount is the difference between the corrected measured current of the line and the preset current limit violation threshold; if the measured current is less than or equal to the threshold, the violation amount is 0.

[0064] If a line with a dispatch demand has a voltage over-limit marker, it is determined that the line has a voltage support demand, and the node with the largest voltage deviation from the rated value in the line is taken as the reactive power compensation point.

[0065] The sum of all currents that need to be transferred corresponding to each dispatching source point is calculated as the total load transfer demand for that dispatching source point. If the same dispatching source point corresponds to multiple load transfer demands (i.e., multiple current-over-limit lines connected to the same node), the combined total load transfer demand will be used as the total current value to be transferred in subsequent steps.

[0066] The number of voltage support requirements corresponding to each reactive power compensation point is counted. If the same reactive power compensation point corresponds to multiple voltage support requirements, they are merged into the voltage support requirements of the reactive power compensation point. Specifically, merging the voltage support requirements of the reactive power compensation point means summing up the reactive power deficits corresponding to all voltage support requirements under that reactive power compensation point. In a specific embodiment, the reactive power compensation amount required for each voltage-over-limit line under that node is calculated. , ,in The system's rated line voltage, For the first Measured voltage of the over-limit line For the first The equivalent reactance of an over-limit line can be obtained by multiplying the reactance per unit length of the line by the line length. Then, sum all the reactive power compensation amounts to get the total reactive power compensation requirement for that reactive power compensation point.

[0067] It should be noted that this method includes all lines downstream of upstream branch nodes in the set of lines requiring dispatch, even if some of these lines are not currently experiencing current or voltage exceedances. The purpose is that, in subsequent load transfers or voltage support dispatching, healthy lines may face new exceedance risks due to taking on transferred loads or adjustments to their operating modes. By marking these lines as lines requiring dispatch, but with a demand of 0, they can be uniformly monitored during candidate line screening, capacity verification, and review steps, ensuring the overall safety of the dispatching scheme. This processing has already been implemented in the dispatching demand assessment step through the absence of demand marking, thus avoiding invalid calculations.

[0068] S3, Candidate Route Search and Scheduling Route Selection

[0069] Based on the distribution network connection relationship, candidate lines for electrical connection of the dispatching line are searched and the remaining carrying capacity of the candidate lines is calculated. The voltage thermal stability of the candidate lines is checked and dispatching lines are selected accordingly, and load transfer is performed.

[0070] For example, calculating the remaining carrying capacity of the candidate line includes obtaining the rated current carrying capacity and measured current of the candidate line.

[0071] Calculate the difference between the rated current carrying capacity and the measured current, and use it as the remaining carrying capacity of the candidate line.

[0072] For example, the voltage thermal stability verification of the candidate line includes: obtaining the line impedance parameters and measured current of the candidate line.

[0073] The total current to be received is obtained by summing the measured current of the candidate line with the total transfer current of the line requiring scheduling.

[0074] Multiply the total current received by the line impedance to obtain the voltage drop at the end of the candidate line.

[0075] The total current and voltage drop values ​​are compared with the thermal stability limit current and the upper limit of allowable voltage drop, respectively.

[0076] If the total current received does not exceed the thermal stability limit current and the voltage drop does not exceed the allowable voltage drop limit, then the candidate line voltage thermal stability is deemed qualified; otherwise, it is deemed unqualified.

[0077] For example, the screening and scheduling of lines includes: sorting candidate lines that are deemed qualified in terms of voltage thermal stability from largest to smallest in terms of remaining capacity.

[0078] The remaining capacity of each candidate line is accumulated sequentially. When the sum is greater than or equal to the total current to be transferred, all candidate lines involved in the accumulation are used as dispatch lines. If the sum of the remaining capacity of all candidate lines is still less than the total current to be transferred, the current dispatch is terminated and an alarm is issued.

[0079] When the selected dispatch lines include multiple lines, the total current to be transferred is allocated according to the proportion of the remaining carrying capacity of each line. Then, the tie switches corresponding to each dispatch line are closed simultaneously, and the corresponding sectionalizing switches are opened to execute parallel load transfer.

[0080] It should be noted that when there are multiple lines with scheduling needs that require load transfer, this method sequentially performs steps S3 to S4 on each line with scheduling needs, and updates the remaining capacity of the relevant lines after each load transfer for subsequent scheduling use.

[0081] S4. Review and Closed-Loop Correction

[0082] After a preset delay period, the electrical parameters of the requested and dispatched lines are checked to determine whether the dispatch objective is met. The preset delay period is set based on the actual operating conditions of the distribution network; in a specific implementation, for medium-voltage distribution networks, this period is 10–30 seconds. If the dispatch objective is met, the current dispatch ends; otherwise, the following anti-looping process is executed: the number of loop iterations is accumulated, initially 0, and incremented by 1 for each return.

[0083] First, perform a rollback operation: disconnect the closed connecting switches in this scheduling, close the disconnected section switches, and restore the operation mode to that before scheduling.

[0084] Then, all the selected scheduling lines are temporarily marked as unavailable, and these lines will not be considered in subsequent loops.

[0085] If the cumulative number of cycles does not exceed the preset maximum number of cycles (3 in this embodiment), then return to step S1: electrical parameter acquisition and spatial collaborative correction step according to the reviewed electrical parameters, and re-execute the candidate line search and screening.

[0086] If the cumulative number of cycles exceeds the preset maximum number of cycles, or if the currently available candidate lines (i.e., lines not marked as unavailable) can no longer meet the total transfer current requirement through sorting and accumulation (e.g., the sum of the remaining capacity of the remaining candidate lines is less than the total transfer current requirement), then the current scheduling will be terminated and an alarm signal will be issued.

[0087] It should be noted that marking a line as unavailable means temporarily removing it during the current scheduling process to avoid repeatedly selecting the same line and causing the loop to fail to converge. Furthermore, if all candidate lines are marked as unavailable or have insufficient remaining total capacity during the anti-loop processing, the current scheduling will also be terminated and an alarm will be issued.

[0088] For example, determining whether the scheduling objective is met includes: obtaining the measured current and measured voltage of the line requiring scheduling after review and the line being scheduled.

[0089] If the measured current of the dispatched line does not exceed the preset current over-limit threshold, and the measured voltage is within the preset voltage threshold range, and the measured current of the dispatched line does not exceed its thermal stability limit current, then the dispatch target is deemed to be met; otherwise, it is deemed not to be met.

[0090] This invention constructs a complete closed-loop process for distribution network dispatch control based on a dedicated transformer acquisition terminal through the aforementioned steps S1 to S4. Spatial collaborative correction eliminates the interference of measured data deviations on dispatch decisions, and post-execution delay review and closed-loop correction ensure the reliable achievement of dispatch objectives, effectively improving the accuracy, adaptability, and economy of distribution network dispatch.

[0091] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented, in whole or in part, in the form of a computer program product.

[0092] Those skilled in the art will recognize that the modules and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0093] In addition, the functional modules in the various embodiments of this application can be integrated into one processing module, or each module can exist physically separately, or two or more modules can be integrated into one module.

[0094] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0095] Finally, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A distribution network dispatching and control method based on a dedicated transformer data acquisition terminal, characterized in that: The method includes: The measured current and voltage of multiple lines are collected synchronously through the dedicated transformer acquisition terminal. Based on the upstream and downstream connection relationship and adjacent parallel relationship of the lines, the consistency verification of the measured current of each downstream branch line with the measured current of the upstream total line is performed, as well as the consistency verification of the measured voltage drop of adjacent lines. The corrected electrical parameters are obtained based on the verification results. The corrected electrical parameters are compared with the preset over-limit thresholds to locate the dispatch demand lines and assess their dispatch demand. Specifically, lines marked as current over-limit or voltage over-limit are taken as the initial dispatch demand lines. According to the distribution network topology, the upstream adjacent branch nodes that are directly electrically connected to the initial dispatch demand lines are traced, and all lines located downstream of the branch node and electrically connected to the initial dispatch demand lines are taken as dispatch demand lines. Based on the distribution network connection relationship, candidate lines for electrical connection of the dispatch demand are searched, the remaining carrying capacity of the candidate lines is calculated, and the voltage thermal stability of the candidate lines is checked. Based on this, dispatch lines are selected and load transfer is performed. After a preset delay, the electrical parameters of the scheduling demand line and the scheduling line are checked to determine whether the scheduling objective is met. If the scheduling objective is met, the current scheduling ends; otherwise, based on the checked electrical parameters, the process returns to the electrical parameter acquisition and spatial collaborative correction step. The consistency verification of the measured current of each downstream branch line with the measured current of the upstream main line includes: Obtain the measured current of the upstream main line and each downstream branch line collected by the same dedicated transformer acquisition terminal; The measured currents of each downstream branch line are summed, and the residual between the downstream branch line current and the measured current of the upstream total line is calculated. If the residual exceeds the preset threshold, it is determined that there is a current deviation. After determining that there is a current deviation, for each downstream branch line, the deviation rate between the measured current and the historical average value of the line is calculated, and the branch lines with a deviation rate greater than the preset lower limit of the deviation rate are designated as lines to be corrected. Calculate the difference between the measured current of the upstream total line and the sum of the measured currents of all non-corrected lines, and use this difference as the total correction current. Calculate the sum of the measured current values ​​of all lines to be corrected as the total measured current of the lines to be corrected. Divide the measured current value of each line to be corrected by the total measured current of the lines to be corrected to obtain the allocation ratio of each line to be corrected. Then multiply the total correction current by the allocation ratio to obtain the correction current of each line to be corrected.

2. The distribution network dispatching and control method based on a dedicated transformer acquisition terminal according to claim 1, characterized in that: The consistency check of voltage drop across adjacent lines includes: Obtain the measured voltages at the beginning and end of adjacent lines, take the difference between the measured voltages at the beginning and end as the measured voltage drop, and calculate the theoretical voltage drop based on the line impedance parameters and the measured current flowing through the line. The measured voltage drop is compared with the theoretical voltage drop, and the deviation is calculated. If the deviation exceeds the preset voltage deviation threshold, the corresponding line is determined to have a voltage anomaly and the line is marked as a line whose voltage needs to be corrected. Traverse all adjacent lines, collect the set of all lines marked as having voltage to be corrected, and treat the adjacent lines not marked as having voltage to be corrected as adjacent healthy lines. For each line whose voltage needs to be corrected, the correction voltage of the line whose voltage needs to be corrected is calculated by interpolation, with reference to the voltage drop coefficient of the adjacent healthy line.

3. The distribution network dispatching and control method based on a dedicated transformer acquisition terminal according to claim 1, characterized in that: The acquisition of the corrected electrical parameters includes: For branch lines that have undergone current correction, the corrected current is used as the corrected current of the line; otherwise, the measured current is used as the corrected current of the line. For lines that have undergone voltage correction, the corrected voltage shall be used as the corrected voltage of the line; otherwise, the measured voltage shall be used as the corrected voltage of the line. The corrected current and corrected voltage are used together as the corrected electrical parameters.

4. The distribution network dispatching and control method based on a dedicated transformer acquisition terminal according to claim 1, characterized in that: The line marking methods for current or voltage exceeding limits include: The corrected current of each line is compared with the preset current over-limit threshold. If the current exceeds the threshold, the line is marked as a current over-limit line. The corrected voltage of each line is compared with the preset voltage threshold range. If the voltage is lower than the lower threshold or higher than the upper threshold, the line is marked as a voltage over-limit line.

5. The distribution network dispatching and control method based on a dedicated transformer acquisition terminal according to claim 1, characterized in that: The scheduling requirements of the lines being evaluated include: For lines with scheduling needs that do not have current over-limit markers or voltage over-limit markers, their scheduling needs are marked as no need. If a line with a current limit exceeding the limit has a current limit exceeding the limit, it is determined that the line has a load transfer requirement. The current limit exceeding the limit of the line is calculated as the current to be transferred for the line, and the access node of the line is used as the dispatch source point. If a line with a dispatch demand has a voltage over-limit marker, it is determined that the line has a voltage support demand, and the node with the largest voltage deviation from the rated value in the line is taken as the reactive power compensation point. The sum of all currents that need to be transferred corresponding to each scheduling source point is counted as the total load transfer demand of that scheduling source point; Count the voltage support demand corresponding to each reactive power compensation point. If the same reactive power compensation point corresponds to multiple voltage support demands, then merge them into the voltage support demand of the reactive power compensation point.

6. The distribution network dispatching and control method based on a dedicated transformer acquisition terminal according to claim 1, characterized in that: The remaining capacity of the candidate lines is calculated as follows: Obtain the rated current carrying capacity and measured current of the candidate circuit; Calculate the difference between the rated current carrying capacity and the measured current, and use it as the remaining carrying capacity of the candidate line.

7. The distribution network dispatching and control method based on a dedicated transformer acquisition terminal according to claim 1, characterized in that: The voltage thermal stability of the candidate circuit being checked includes: Obtain the line impedance parameters and measured current of the candidate lines; The total current to be received is obtained by summing the measured current of the candidate line with the total transfer current of the line requiring scheduling. Multiply the total current received by the line impedance to obtain the voltage drop value at the end of the candidate line; The total current and voltage drop values ​​are compared with the thermal stability limit current and the upper limit of the allowable voltage drop, respectively. If the total current received does not exceed the thermal stability limit current and the voltage drop does not exceed the allowable voltage drop limit, then the candidate line voltage thermal stability is deemed qualified; otherwise, it is deemed unqualified.

8. The distribution network dispatching and control method based on a dedicated transformer acquisition terminal according to claim 7, characterized in that: The screening and scheduling lines include: Candidate lines that pass the voltage thermal stability test are sorted from largest to smallest according to their remaining capacity. The remaining capacity of each candidate line is accumulated sequentially. When the sum is greater than or equal to the total current to be transferred, all candidate lines involved in the accumulation are used as dispatch lines. If the sum of the remaining capacity of all candidate lines is still less than the total current to be transferred, the current dispatch is terminated and an alarm is issued.

9. The distribution network dispatching and control method based on a dedicated transformer acquisition terminal according to claim 1, characterized in that: The determination of whether the scheduling objective is met includes: Obtain the measured current and voltage of the dispatched lines and the dispatched lines after the review; If the measured current of the dispatched line does not exceed the preset current over-limit threshold, and the measured voltage is within the preset voltage threshold range, and the measured current of the dispatched line does not exceed its thermal stability limit current, then the dispatch target is deemed to be met; otherwise, it is deemed not to be met.

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