A method, system, device, medium, and product for optimizing the state of an ultra-high voltage power grid.

Abstract

This application discloses a method, system, device, medium, and product for optimizing the state of an ultra-high voltage (UHV) power grid, relating to the field of UHV engineering evaluation technology. The method includes: determining the target initial operating state of the UHV power grid, initial first power flow solution, initial second power flow solution, initial third power flow solution, initial load change step size, target node, and initial corrected power flow solution; performing multiple rounds of first iterations on the corrected power flow solution to obtain the first target corrected power flow solution; if the DC voltage exceeds the limit, adjusting the switching strategy of each capacitor bank in the UHV power grid, performing multiple rounds of second iterations on the corrected power flow solution to obtain the second target corrected power flow solution, and performing power flow calculations to obtain the critical judgment power flow solution; if the preset critical point is not reached, performing multiple rounds of third iterations on the corrected power flow solution; otherwise, determining the operating state corresponding to the third target corrected power flow solution as the final operating state of the UHV power grid. This application ensures the stable operation of the UHV power grid.

Description

Technical Field

[0001] This application relates to the field of ultra-high voltage (UHV) engineering evaluation technology, and in particular to a method, system, device, medium, and product for optimizing the state of an UHV power grid. Background Technology

[0002] Ultra-high voltage (UHV) power transmission technology has been vigorously developed and applied in the field of ultra-long-distance and ultra-large-capacity power transmission from large energy bases, becoming a key technology and important guarantee for breaking resource bottlenecks and optimizing energy allocation. As the backbone grid for clean energy transmission, during the 14th Five-Year Plan period, UHV power transmission technology will rely on clean energy bases to coordinate the construction of UHV DC channels, continue to expand the transmission and absorption capacity and scope of clean energy, accelerate the construction of a new power system with new energy as the main body, and build a clean, low-carbon, safe, and efficient energy supply, transmission, and absorption system as soon as possible, contributing to China's clean and low-carbon energy upgrading and transformation, and achieving the "3060 dual-carbon" target.

[0003] China's primary energy and electricity load distribution is uneven, with abundant energy resources in the west and a concentrated electricity load in the economically developed east. This uneven distribution necessitates large-scale, long-distance power transmission technologies to address the geographical disparities between energy supply and demand. By the end of 2020, China had completed 35 ultra-high-voltage (UHV) projects, including 14 AC and 16 DC lines, with a total line length of 48,000 kilometers. Investment in UHV projects experienced rapid growth between 2014 and 2020, reaching 196.6 billion yuan.

[0004] Against the backdrop of peak carbon emissions and carbon neutrality, ultra-high voltage (UHV) power grids will continue to play a vital role in optimizing the energy structure, promoting the development of clean energy, and achieving large-scale energy allocation. As a key technology for solving the problem of large-scale, long-distance power transmission, the research and application of UHV technology are of great significance for optimizing the energy structure, promoting the development of clean energy, and achieving large-scale energy allocation.

[0005] With the rapid development of ultra-high voltage power grids, requirements have been put forward for their stable operation. Summary of the Invention

[0006] The purpose of this application is to provide a method, system, device, medium, and product for optimizing the state of ultra-high voltage power grids, thereby ensuring the stable operation of ultra-high voltage power grids.

[0007] To achieve the above objectives, this application provides the following solution:

[0008] Firstly, this application provides a method for optimizing the state of an ultra-high voltage power grid, including:

[0009] Determine the target initial operating state, initial first power flow solution, initial second power flow solution, initial third power flow solution, and initial load change step size of the UHV power grid; each power flow solution includes: load and voltage;

[0010] Based on the voltage of each operating node in the UHV power grid under the initial first power flow solution and the voltage of each operating node under the initial third power flow solution, the target node is determined; the target node is the operating node with the largest difference between the voltage under the initial first power flow solution and the voltage under the initial third power flow solution.

[0011] Using Newton's interpolation method, the initial first, second, and third power flow solutions of the target node are fitted to obtain an initial fitted curve. The extreme points and extreme values ​​of the initial fitted curve are determined and used as the initial predicted power flow solutions. Based on the initial predicted power flow solutions, power flow calculations are performed to obtain the initial corrected power flow solutions. The horizontal axis of the fitted curve represents the load, and the vertical axis represents the voltage.

[0012] Based on the initial corrected power flow solution, the first target corrected power flow solution is obtained by updating the load change step size and performing multiple rounds of first iterations on the corrected power flow solution.

[0013] Determine whether the DC voltage exceeds the limit; if it does, adjust the switching strategy of each capacitor bank in the UHV grid until it does not exceed the limit, all capacitor banks are fully engaged or all capacitor banks are deactivated. Based on the first objective corrected power flow solution, the corrected power flow solution is iterated multiple times by updating the load change step size to obtain the second objective corrected power flow solution.

[0014] Based on the corrected power flow solution of the second objective, power flow calculation is performed to obtain the initial critical judgment power flow solution;

[0015] Determine whether the initial critical point has been reached;

[0016] If the target is not reached, the corrected power flow solution based on the second objective is then iterated multiple times in the third round by updating the load change step size until the preset critical point is reached, thus obtaining the corrected power flow solution for the third objective.

[0017] If the target is achieved, the operating state corresponding to the third target power flow solution will be determined as the final operating state of the UHV power grid.

[0018] Optionally, the target initial operating state and initial first power flow solution of the UHV power grid are determined, including:

[0019] Initialize the operating status of the ultra-high voltage power grid;

[0020] Based on the initial operating state and power flow calculation of the UHV power grid, the operating state of the UHV power grid is iterated multiple times to obtain the target initial operating state and the initial first power flow solution; wherein, the iteration process in any current round includes:

[0021] Based on the operating state in the current round, power flow calculation is performed to obtain the initial power flow solution for the current round;

[0022] Based on the load in the initial power flow solution of the current round, determine whether the power flow has converged in the current iteration round, and obtain the first convergence judgment result of the current round;

[0023] If the first convergence judgment result in the current round is convergence, then the operating state in the current round is determined as the target initial operating state, and the initial power flow solution in the current round is determined as the initial first power flow solution;

[0024] If the first convergence judgment result in the current round is non-convergence, then update the running state in the current round to the running state in the next round, and return "Calculate the power flow based on the running state in the current round to obtain the initial power flow solution in the current round", until the initial first power flow solution is obtained.

[0025] Optionally, determining the initial second power flow solution, the initial third power flow solution, and the initial load change step size of the UHV power grid includes:

[0026] Initialize the load change step size under the target's initial operating state;

[0027] Using the Newton-Raphson method, the load change step size of the UHV power grid is iterated multiple times to obtain the initial second power flow solution, the initial third power flow solution, and the initial load change step size. The iteration process in any given round includes:

[0028] Using the Newton-Raphson method, based on the initial first power flow solution and the load change step size in the current cycle, the second and third power flow solutions in the current cycle are determined;

[0029] Based on the second and third power flow solutions in the current round, determine whether the power flow has converged in the current iteration round, and obtain the second convergence judgment result in the current round;

[0030] If the second convergence judgment result in the current round is convergence, then the second power flow solution in the current round is determined as the initial second power flow solution, the third power flow solution in the current round is determined as the initial third power flow solution, and the load change step size in the current round is determined as the initial load change step size;

[0031] If the second convergence judgment result in the current round is non-convergence, then update the load change step size in the current round to the load change step size in the next round, and return "Using the Newton-Raphson method, based on the initial first power flow solution and the load change step size in the current round, determine the second power flow solution and the third power flow solution in the current round", until the initial second power flow solution, the initial third power flow solution and the initial load change step size are obtained.

[0032] Optionally, based on the initial corrected power flow solution, the corrected power flow solution is iterated multiple times in the first iteration by updating the load change step size to obtain the first target corrected power flow solution, including:

[0033] The iterative process of the corrected power flow solution in any current first iteration includes:

[0034] Obtain the initial second power flow solution, the initial third power flow solution, and the initial load change step size under the current first iteration round;

[0035] Based on the voltage of each operating node in the UHV power grid under the initial first power flow solution in the current first iteration round and the voltage of each operating node under the initial third power flow solution, the target node in the current first iteration round is determined.

[0036] Using Newton's interpolation method, the initial first, second, and third power flow solutions of the target node in the current first iteration are fitted to obtain the fitted curve in the current first iteration. The extreme points and extreme values ​​of the fitted curve in the current first iteration are determined. The extreme points and extreme values ​​in the current first iteration are determined as the predicted power flow solution in the current first iteration. Based on the predicted power flow solution in the current first iteration, power flow calculation is performed to obtain the corrected power flow solution in the current first iteration.

[0037] Based on the load in the corrected power flow solution under the current first iteration, determine whether the power flow has converged under the current first iteration, and obtain the third convergence judgment result under the current first iteration;

[0038] If the third convergence judgment result in the current first iteration round is convergence, then the corrected power flow solution in the current first iteration round is determined as the first target corrected power flow solution;

[0039] If the third convergence judgment result under the current first iteration round is non-convergence, then the initial second power flow solution, initial third power flow solution and initial load change step size under the current first iteration round are updated to the initial second power flow solution, initial third power flow solution and initial load change step size under the next first iteration round, and the function returns "Based on the voltage of each operating node in the UHV power grid under the initial first power flow solution under the current first iteration round and the voltage of each operating node under the initial third power flow solution, determine the target node under the current first iteration round", until the first target corrected power flow solution is obtained.

[0040] Alternatively, the expression for the fitted curve is:

[0041]

[0042] Where λ is the load; a is the coefficient of the quadratic term; U k λ is the voltage at the target node; b is the coefficient of the first-order term; c is the constant term; a1, a2, and a3 are intermediate quantities; λ A For the load in the first tidal current solution; λ B For the load in the second tidal current solution; U kA Solve the voltage of the target node for the first power flow; U kB Solve for the voltage of the target node for the second power flow; λ C For the load in the third tidal current solution; U kC The voltage of the target node is reduced for the third power flow.

[0043] Optionally, based on the first objective corrected power flow solution, the corrected power flow solution is iterated multiple times in the second round by updating the load change step size to obtain the second objective corrected power flow solution, including:

[0044] The iterative process of the corrected power flow solution in any current second iteration includes:

[0045] Obtain the initial second power flow solution, the initial third power flow solution, and the initial load change step size under the current second iteration round;

[0046] Based on the voltage of each operating node in the UHV power grid under the initial first power flow solution in the current second iteration round and the voltage of each operating node under the initial third power flow solution, the target node in the current second iteration round is determined.

[0047] Using Newton's interpolation method, the initial first, second, and third power flow solutions of the target node in the current second iteration are fitted to obtain the fitted curve in the current second iteration. The extreme points and extreme values ​​of the fitted curve in the current second iteration are determined. The extreme points and extreme values ​​in the current second iteration are determined as the predicted power flow solution in the current second iteration. Based on the predicted power flow solution in the current second iteration, power flow calculation is performed to obtain the corrected power flow solution in the current second iteration.

[0048] Based on the load in the corrected power flow solution under the current second iteration, determine whether the power flow has converged under the current second iteration, and obtain the fourth convergence judgment result under the current second iteration;

[0049] If the fourth convergence judgment result in the current second iteration is convergence, then the corrected power flow solution in the current second iteration is determined as the second target corrected power flow solution;

[0050] If the fourth convergence judgment result under the current second iteration round is non-convergence, then the initial second power flow solution, initial third power flow solution and initial load change step size under the current second iteration round are updated to the initial second power flow solution, initial third power flow solution and initial load change step size under the next second iteration round, and the function returns "Based on the voltage of each operating node in the UHV power grid under the initial first power flow solution under the current second iteration round and the voltage of each operating node under the initial third power flow solution, determine the target node under the current second iteration round", until the second target corrected power flow solution is obtained.

[0051] Optionally, based on the second objective corrected power flow solution, the corrected power flow solution is iterated multiple times in the third round by updating the load change step size until a preset critical point is reached, to obtain the third objective corrected power flow solution, including:

[0052] The iterative process of the corrected power flow solution in any current third iteration includes:

[0053] Obtain the initial second power flow solution, the initial third power flow solution, and the initial load change step size under the current third iteration;

[0054] Based on the voltage of each operating node in the UHV power grid under the initial first power flow solution in the current third iteration round and the voltage of each operating node under the initial third power flow solution, the target node in the current third iteration round is determined.

[0055] Using Newton's interpolation method, the initial first, second, and third power flow solutions of the target node in the current third iteration are fitted to obtain the fitted curve in the current third iteration. The extreme points and extreme values ​​of the fitted curve in the current third iteration are determined. The extreme points and extreme values ​​in the current third iteration are determined as the predicted power flow solution in the current third iteration. Based on the predicted power flow solution in the current third iteration, power flow calculation is performed to obtain the corrected power flow solution in the current third iteration.

[0056] Based on the corrected power flow solution in the current third iteration, determine whether the preset critical point has been reached in the current third iteration, and obtain the fifth convergence judgment result in the current third iteration.

[0057] If the fifth convergence judgment result under the current third iteration is convergence, then the corrected power flow solution under the current third iteration is determined as the third target corrected power flow solution;

[0058] If the fifth convergence judgment result under the current third iteration is non-convergence, then the initial second power flow solution, initial third power flow solution, and initial load change step size under the current third iteration are updated to the initial second power flow solution, initial third power flow solution, and initial load change step size under the next third iteration, and the function returns "Based on the voltage of each operating node in the UHV power grid under the initial first power flow solution under the current third iteration and the voltage of each operating node under the initial third power flow solution, determine the target node under the current third iteration", until the third target corrected power flow solution is obtained.

[0059] Secondly, this application provides a computer device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the ultra-high voltage power grid state optimization method described in any of the above claims.

[0060] Thirdly, this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the ultra-high voltage power grid state optimization method described in any of the above claims.

[0061] Fourthly, this application provides a computer program product, including a computer program that, when executed by a processor, implements the ultra-high voltage power grid state optimization method described in any of the above claims.

[0062] According to the specific embodiments provided in this application, the following technical effects are disclosed:

[0063] This application discloses a method, system, device, medium, and product for optimizing the state of an ultra-high voltage (UHV) power grid. First, the target initial operating state, initial first power flow solution, initial second power flow solution, initial third power flow solution, and initial load change step size of the UHV power grid are determined. Based on the voltage of each operating node in the UHV power grid under the initial first power flow solution and the voltage of each operating node under the initial third power flow solution, the target node is determined. Using Newton's interpolation method, the initial first, second, and third power flow solutions of the target node are fitted to obtain an initial fitted curve. The extreme points and extreme values ​​of the initial fitted curve are determined and used as the initial predicted power flow solution. Based on the initial predicted power flow solution, power flow calculation is performed to obtain the initial corrected power flow solution. Second, based on the initial corrected power flow solution, the corrected power flow solution is processed in multiple rounds by updating the load change step size. The process involves one iteration to obtain the first target corrected power flow solution. Then, it is determined whether the DC voltage exceeds the limit. If it does, the switching strategy of each capacitor bank in the UHV grid is adjusted until the limit is not exceeded, all capacitor banks are fully engaged, or all capacitor banks are deactivated. Based on the first target corrected power flow solution, multiple rounds of second iterations are performed by updating the load change step size to obtain the second target corrected power flow solution. Based on the second target corrected power flow solution, power flow calculations are performed to obtain the initial critical judgment power flow solution. Finally, it is determined whether the initial critical judgment power flow solution reaches the preset critical point. If not, multiple rounds of third iterations are performed based on the second target corrected power flow solution by updating the load change step size until the preset critical point is reached to obtain the third target corrected power flow solution. If the critical point is reached, the operating state corresponding to the third target corrected power flow solution is determined as the final operating state of the UHV grid. This application determines the final operating state of the UHV grid by repeatedly updating the load change step size and the capacitor bank switching strategy, thus ensuring the stable operation of the UHV grid. Attached Figure Description

[0064] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0065] Figure 1 This is a schematic flowchart of an ultra-high voltage power grid state optimization method provided in an embodiment of this application;

[0066] Figure 2 This is a schematic diagram of the load voltage curve;

[0067] Figure 3 This is a schematic diagram of the structure of a computer device provided in an embodiment of this application. Detailed Implementation

[0068] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0069] The purpose of this application is to provide a method, system, device, medium, and product for optimizing the state of ultra-high voltage power grids, aiming to ensure the stable operation of ultra-high voltage power grids.

[0070] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0071] In one exemplary embodiment, such as Figure 1 As shown, the ultra-high voltage power grid state optimization method in this embodiment includes:

[0072] Step 1: Determine the target initial operating state, initial first power flow solution, initial second power flow solution, initial third power flow solution, and initial load change step size of the UHV power grid.

[0073] Each power flow solution includes: load and voltage.

[0074] Step 2: Determine the target node based on the voltage of each operating node in the UHV power grid under the initial first power flow solution and the voltage of each operating node under the initial third power flow solution.

[0075] The target node is the operating node with the largest difference between the voltage under the initial first power flow solution and the voltage under the initial third power flow solution.

[0076] Step 3: Using Newton's interpolation method, fit the initial first, second, and third tidal current solutions of the target node to obtain the initial fitted curve, determine the extreme points and extreme values ​​of the initial fitted curve, and use the extreme points and extreme values ​​of the initial fitted curve as the initial predicted tidal current solution. Based on the initial predicted tidal current solution, perform tidal current calculation to obtain the initial corrected tidal current solution.

[0077] In this curve, the horizontal axis represents the load, and the vertical axis represents the voltage.

[0078] Step 4: Based on the initial corrected power flow solution, the corrected power flow solution is iterated multiple times in the first round by updating the load change step size to obtain the first target corrected power flow solution.

[0079] Step 5: Determine if the DC voltage exceeds the limit; if it does, adjust the switching strategy of each capacitor bank in the UHV grid until it does not exceed the limit, all capacitor banks are fully engaged or all capacitor banks are deactivated. Based on the first objective corrected power flow solution, the second objective corrected power flow solution is obtained by updating the load change step size and performing multiple rounds of second iterations.

[0080] Step 6: Based on the second objective corrected power flow solution, perform power flow calculation to obtain the initial critical judgment power flow solution.

[0081] Step 7: Determine the initial critical point to see if the power flow solution has reached the preset critical point.

[0082] Step 8: If the target is not reached, then based on the second objective corrected power flow solution, the corrected power flow solution is iterated multiple times in the third round by updating the load change step size until the preset critical point is reached, and the third objective corrected power flow solution is obtained.

[0083] Step 9: If achieved, the operating state corresponding to the third target corrected power flow solution is determined as the final operating state of the UHV power grid.

[0084] Furthermore, after step 9, the method also includes: calculating the values ​​of each indicator in the final operating state, including: active power margin, active power reserve coefficient, effective short-circuit ratio, and voltage stability.

[0085] The formula for calculating active power margin is:

[0086]

[0087] Among them, D P For active margin; P max P0 is the static voltage stability limit; S is the active power output under final operating conditions. B This represents the system's baseline capacity.

[0088] The formula for calculating the active power reserve coefficient is:

[0089]

[0090] Among them, D P % represents the active power reserve coefficient.

[0091] The formula for calculating the effective short-circuit ratio is:

[0092]

[0093] Wherein, ESCR is the effective short-circuit ratio; S ac Q represents the short-circuit capacity of the system. c For the reactive power compensation capacity of the converter station; P dc It delivers the actual active power to the system in its final operating state.

[0094] The formula for calculating voltage stability is:

[0095]

[0096] Where VSI represents voltage stability; Q dc U represents the actual reactive power absorbed by the system in its final operating state; U represents the bus voltage in its final operating state.

[0097] As an optional implementation, step 1, determining the target initial operating state and initial first power flow solution of the UHV power grid, includes:

[0098] Step 101: Initialize the operating status of the UHV power grid.

[0099] Step 102: Based on the initial operating state and power flow calculation of the UHV power grid, perform multiple iterations on the operating state of the UHV power grid to obtain the target initial operating state and the initial first power flow solution. The iteration process in any given round includes:

[0100] Step 1021: Perform power flow calculation based on the operating state in the current round to obtain the initial power flow solution in the current round.

[0101] Step 1022: Based on the load in the initial power flow solution of the current round, determine whether the power flow has converged in the current iteration round, and obtain the first convergence judgment result of the current round.

[0102] Step 1023: If the first convergence judgment result in the current round is convergence, then the running state in the current round is determined as the target initial running state, and the initial power flow solution in the current round is determined as the initial first power flow solution.

[0103] Step 1024: If the first convergence judgment result in the current round is non-convergence, then update the running state in the current round to the running state in the next round, and return to step 1021 until the initial first power flow solution is obtained.

[0104] As an optional implementation, step 1, determining the initial second power flow solution, the initial third power flow solution, and the initial load change step size of the UHV power grid, includes:

[0105] Step 111: Initialize the load change step size under the initial operating state of the target.

[0106] Step 112: Using the Newton-Raphson method, perform multiple iterations on the load change step size of the UHV power grid to obtain the initial second power flow solution, the initial third power flow solution, and the initial load change step size. The iteration process in any given round includes:

[0107] Step 1121: Using the Newton-Raphson method, based on the initial first power flow solution and the load change step size in the current cycle, determine the second and third power flow solutions in the current cycle.

[0108] Specifically, the formulas for calculating the load in the second and third power flow solutions are as follows:

[0109] λ B =λ A +Δλ.

[0110] λ C =λ B +Δλ.

[0111] Where, λ B For the load in the second tidal current solution; λ A λ represents the load in the first tidal current solution; Δλ is the load change step size; λ C The load in the third current solution.

[0112] Step 1122: Based on the second and third power flow solutions in the current round, determine whether the power flow has converged in the current iteration round, and obtain the second convergence judgment result in the current round.

[0113] Step 1123: If the second convergence judgment result in the current round is convergence, then the second power flow solution in the current round is determined as the initial second power flow solution, the third power flow solution in the current round is determined as the initial third power flow solution, and the load change step size in the current round is determined as the initial load change step size.

[0114] Step 1124: If the second convergence judgment result in the current round is non-convergence, update the load change step size in the current round to the load change step size in the next round, and return to step 1121 until the initial second power flow solution, the initial third power flow solution and the initial load change step size are obtained.

[0115] As an optional implementation, step 4 includes:

[0116] The iterative process of the corrected power flow solution in any current first iteration includes:

[0117] Step 41: Obtain the initial second power flow solution, the initial third power flow solution, and the initial load change step size under the current first iteration round.

[0118] Step 42: Based on the voltage of each operating node in the UHV power grid under the initial first power flow solution in the current first iteration round and the voltage of each operating node under the initial third power flow solution, determine the target node under the current first iteration round.

[0119] Step 43: Using Newton's interpolation method, fit the initial first power flow solution, initial second power flow solution, and initial third power flow solution of the target node in the current first iteration round to obtain the fitted curve in the current first iteration round. Determine the extreme points and extreme values ​​of the fitted curve in the current first iteration round. Use the extreme points and extreme values ​​in the current first iteration round as the predicted power flow solution in the current first iteration round. Based on the predicted power flow solution in the current first iteration round, perform power flow calculation to obtain the corrected power flow solution in the current first iteration round.

[0120] Specifically, such as Figure 2 As shown, the fitted curve is a parabola, with its extreme values ​​close to the static voltage stability limit of the PV curve. The extreme points and extreme values ​​can be expressed as (U cr ,λ max ).

[0121]

[0122] Among them, U cr The extreme point; λ max It is an extreme value.

[0123] Step 44: Based on the load in the corrected power flow solution under the current first iteration, determine whether the power flow has converged under the current first iteration, and obtain the third convergence judgment result under the current first iteration.

[0124] Step 45: If the third convergence judgment result in the current first iteration is convergence, then the corrected power flow solution in the current first iteration is determined as the first target corrected power flow solution.

[0125] Step 46: If the third convergence judgment result under the current first iteration round is non-convergence, then update the initial second power flow solution, initial third power flow solution and initial load change step size under the current first iteration round to the initial second power flow solution, initial third power flow solution and initial load change step size under the next first iteration round, and return to step 42 until the first target corrected power flow solution is obtained.

[0126] As an optional implementation, the expression for the fitted curve is:

[0127]

[0128] Where λ is the load; a is the coefficient of the quadratic term; U k λ is the voltage at the target node; b is the coefficient of the first-order term; c is the constant term; a1, a2, and a3 are intermediate quantities; λ A For the load in the first tidal current solution; λ B For the load in the second tidal current solution; U kA Solve the voltage of the target node for the first power flow; U kBSolve for the voltage of the target node for the second power flow; λ C For the load in the third tidal current solution; U kC The voltage at the target node is reduced for the third power flow.

[0129] As an optional implementation, step 5, based on the first target corrected power flow solution, involves updating the load change step size and performing multiple rounds of second iterations on the corrected power flow solution to obtain the second target corrected power flow solution, including:

[0130] The iterative process of the corrected power flow solution in any current second iteration includes:

[0131] Step 51: Obtain the initial second power flow solution, the initial third power flow solution, and the initial load change step size under the current second iteration round.

[0132] Step 52: Based on the voltage of each operating node in the UHV power grid under the initial first power flow solution and the voltage of each operating node under the initial third power flow solution in the current second iteration round, determine the target node in the current second iteration round.

[0133] Step 53: Using Newton's interpolation method, fit the initial first, second, and third power flow solutions of the target node in the current second iteration to obtain the fitted curve in the current second iteration. Determine the extreme points and extreme values ​​of the fitted curve in the current second iteration. Use the extreme points and extreme values ​​in the current second iteration as the predicted power flow solution in the current second iteration. Based on the predicted power flow solution in the current second iteration, perform power flow calculation to obtain the corrected power flow solution in the current second iteration.

[0134] Step 54: Based on the load in the corrected power flow solution under the current second iteration, determine whether the power flow has converged under the current second iteration, and obtain the fourth convergence judgment result under the current second iteration.

[0135] Step 55: If the fourth convergence judgment result in the current second iteration is convergence, then the corrected power flow solution in the current second iteration is determined as the second target corrected power flow solution.

[0136] Step 56: If the fourth convergence judgment result under the current second iteration round is non-convergence, then update the initial second power flow solution, initial third power flow solution and initial load change step size under the current second iteration round to the initial second power flow solution, initial third power flow solution and initial load change step size under the next second iteration round, and return to step 52 until the second target corrected power flow solution is obtained.

[0137] As an optional implementation, step 8 includes:

[0138] The iterative process of the corrected power flow solution in any current third iteration includes:

[0139] Step 81: Obtain the initial second power flow solution, the initial third power flow solution, and the initial load change step size under the current third iteration.

[0140] Step 82: Based on the voltage of each operating node in the UHV power grid under the initial first power flow solution in the current third iteration round and the voltage of each operating node under the initial third power flow solution, determine the target node under the current third iteration round.

[0141] Step 83: Using Newton's interpolation method, fit the initial first power flow solution, initial second power flow solution, and initial third power flow solution of the target node in the current third iteration to obtain the fitted curve in the current third iteration. Determine the extreme points and extreme values ​​of the fitted curve in the current third iteration. Use the extreme points and extreme values ​​in the current third iteration as the predicted power flow solution in the current third iteration. Based on the predicted power flow solution in the current third iteration, perform power flow calculation to obtain the corrected power flow solution in the current third iteration.

[0142] Step 84: Based on the corrected power flow solution in the current third iteration, determine whether the preset critical point has been reached in the current third iteration, and obtain the fifth convergence judgment result in the current third iteration.

[0143] Step 85: If the fifth convergence judgment result under the current third iteration is convergence, then the corrected power flow solution under the current third iteration is determined as the third target corrected power flow solution.

[0144] Step 86: If the fifth convergence judgment result under the current third iteration is non-convergence, then update the initial second power flow solution, initial third power flow solution and initial load change step size under the current third iteration to the initial second power flow solution, initial third power flow solution and initial load change step size under the next third iteration, and return to step 82 until the third target corrected power flow solution is obtained.

[0145] In one exemplary embodiment, a computer device is provided, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement an ultra-high voltage power grid state optimization method.

[0146] In one exemplary embodiment, a computer-readable storage medium is provided having a computer program stored thereon that, when executed by a processor, implements a method for optimizing the state of an ultra-high voltage power grid.

[0147] In one exemplary embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements a method for optimizing the state of an ultra-high voltage power grid.

[0148] In one exemplary embodiment, a computer device is provided, which may be a server or a terminal, and its internal structure diagram may be as follows. Figure 3 As shown, this computer device includes a processor, memory, input / output (I / O) interfaces, and a communication interface. The processor, memory, and I / O interfaces are connected via a system bus, and the communication interface is also connected to the system bus via the I / O interfaces. The processor provides computational and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and databases. The internal memory provides the environment for the operating system and computer programs stored in the non-volatile storage media to run. The I / O interfaces are used for exchanging information between the processor and external devices. The communication interface is used for communicating with external terminals via a network connection. When the computer program is executed by the processor, it implements a method for optimizing the state of an ultra-high voltage power grid.

[0149] Those skilled in the art will understand that Figure 3 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0150] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data must comply with relevant regulations.

[0151] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM).

[0152] The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0153] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0154] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A method for optimizing the state of an ultra-high voltage power grid, characterized in that, The ultra-high voltage power grid state optimization method includes: Determine the target initial operating state, initial first power flow solution, initial second power flow solution, initial third power flow solution, and initial load change step size of the UHV power grid; each power flow solution includes: load and voltage; Based on the voltage of each operating node in the UHV power grid under the initial first power flow solution and the voltage of each operating node under the initial third power flow solution, the target node is determined; the target node is the operating node with the largest difference between the voltage under the initial first power flow solution and the voltage under the initial third power flow solution. Using Newton's interpolation method, the initial first, second, and third power flow solutions of the target node are fitted to obtain an initial fitted curve. The extreme points and extreme values ​​of the initial fitted curve are determined and used as the initial predicted power flow solutions. Based on the initial predicted power flow solutions, power flow calculations are performed to obtain the initial corrected power flow solutions. The horizontal axis of the fitted curve represents the load, and the vertical axis represents the voltage. Based on the initial corrected power flow solution, the first target corrected power flow solution is obtained by updating the load change step size and performing multiple rounds of first iterations on the corrected power flow solution. Determine whether the DC voltage exceeds the limit; if it does, adjust the switching strategy of each capacitor bank in the UHV grid until it does not exceed the limit, all capacitor banks are fully engaged or all capacitor banks are deactivated. Based on the first objective corrected power flow solution, the corrected power flow solution is iterated multiple times by updating the load change step size to obtain the second objective corrected power flow solution. Based on the corrected power flow solution of the second objective, power flow calculation is performed to obtain the initial critical judgment power flow solution; Determine whether the initial critical point has been reached; If the target is not reached, the corrected power flow solution based on the second objective is then iterated multiple times in the third round by updating the load change step size until the preset critical point is reached, thus obtaining the corrected power flow solution for the third objective. If the target is achieved, the operating state corresponding to the third target power flow solution will be determined as the final operating state of the UHV power grid.

2. The ultra-high voltage power grid state optimization method according to claim 1, characterized in that, Determine the target initial operating state and initial first power flow solution of the UHV power grid, including: Initialize the operating status of the ultra-high voltage power grid; Based on the initial operating state and power flow calculation of the UHV power grid, the operating state of the UHV power grid is iterated multiple times to obtain the target initial operating state and the initial first power flow solution; wherein, the iteration process in any current round includes: Based on the operating state in the current round, power flow calculation is performed to obtain the initial power flow solution for the current round; Based on the load in the initial power flow solution of the current round, determine whether the power flow has converged in the current iteration round, and obtain the first convergence judgment result of the current round; If the first convergence judgment result in the current round is convergence, then the operating state in the current round is determined as the target initial operating state, and the initial power flow solution in the current round is determined as the initial first power flow solution; If the first convergence judgment result in the current round is non-convergence, then update the running state in the current round to the running state in the next round, and return "Calculate the power flow based on the running state in the current round to obtain the initial power flow solution in the current round", until the initial first power flow solution is obtained.

3. The ultra-high voltage power grid state optimization method according to claim 2, characterized in that, Determining the initial second power flow solution, the initial third power flow solution, and the initial load change step size of the UHV power grid includes: Initialize the load change step size under the target's initial operating state; Using the Newton-Raphson method, the load change step size of the UHV power grid is iterated multiple times to obtain the initial second power flow solution, the initial third power flow solution, and the initial load change step size. The iteration process in any given round includes: Using the Newton-Raphson method, based on the initial first power flow solution and the load change step size in the current cycle, the second and third power flow solutions in the current cycle are determined; Based on the second and third power flow solutions in the current round, determine whether the power flow has converged in the current iteration round, and obtain the second convergence judgment result in the current round; If the second convergence judgment result in the current round is convergence, then the second power flow solution in the current round is determined as the initial second power flow solution, the third power flow solution in the current round is determined as the initial third power flow solution, and the load change step size in the current round is determined as the initial load change step size; If the second convergence judgment result in the current round is non-convergence, then update the load change step size in the current round to the load change step size in the next round, and return to "Using the Newton-Raphson method, based on the initial first power flow solution and the load change step size in the current round, determine the second power flow solution and the third power flow solution in the current round", until the initial second power flow solution, the initial third power flow solution and the initial load change step size are obtained.

4. The ultra-high voltage power grid state optimization method according to claim 3, characterized in that, Based on the initial corrected power flow solution, the corrected power flow solution is iterated multiple times in the first round by updating the load change step size to obtain the first target corrected power flow solution, including: The iterative process of the corrected power flow solution in any current first iteration includes: Obtain the initial second power flow solution, the initial third power flow solution, and the initial load change step size under the current first iteration round; Based on the voltage of each operating node in the UHV power grid under the initial first power flow solution in the current first iteration round and the voltage of each operating node under the initial third power flow solution, the target node in the current first iteration round is determined. Using Newton's interpolation method, the initial first, second, and third power flow solutions of the target node in the current first iteration are fitted to obtain the fitted curve in the current first iteration. The extreme points and extreme values ​​of the fitted curve in the current first iteration are determined. The extreme points and extreme values ​​in the current first iteration are determined as the predicted power flow solution in the current first iteration. Based on the predicted power flow solution in the current first iteration, power flow calculation is performed to obtain the corrected power flow solution in the current first iteration. Based on the load in the corrected power flow solution under the current first iteration, determine whether the power flow has converged under the current first iteration, and obtain the third convergence judgment result under the current first iteration; If the third convergence judgment result in the current first iteration round is convergence, then the corrected power flow solution in the current first iteration round is determined as the first target corrected power flow solution; If the third convergence judgment result under the current first iteration round is non-convergence, then the initial second power flow solution, initial third power flow solution and initial load change step size under the current first iteration round are updated to the initial second power flow solution, initial third power flow solution and initial load change step size under the next first iteration round, and the function returns "Based on the voltage of each operating node in the UHV power grid under the initial first power flow solution under the current first iteration round and the voltage of each operating node under the initial third power flow solution, determine the target node under the current first iteration round", until the first target corrected power flow solution is obtained.

5. The ultra-high voltage power grid state optimization method according to claim 4, characterized in that, The expression for the fitted curve is: Where λ is the load; a is the coefficient of the quadratic term; U k λ is the voltage at the target node; b is the coefficient of the first-order term; c is the constant term; a1, a2, and a3 are intermediate quantities; λ A For the load in the first tidal current solution; λ B For the load in the second tidal current solution; U kA Solve the voltage of the target node for the first power flow; U kB Solve for the voltage of the target node for the second power flow; λ C For the load in the third tidal current solution; U kC The voltage of the target node is reduced for the third power flow.

6. The ultra-high voltage power grid state optimization method according to claim 5, characterized in that, Based on the first objective corrected power flow solution, the second objective corrected power flow solution is obtained by updating the load change step size and performing multiple rounds of second iterations, including: The iterative process of the corrected power flow solution in any current second iteration includes: Obtain the initial second power flow solution, the initial third power flow solution, and the initial load change step size under the current second iteration round; Based on the voltage of each operating node in the UHV power grid under the initial first power flow solution in the current second iteration round and the voltage of each operating node under the initial third power flow solution, the target node in the current second iteration round is determined. Using Newton's interpolation method, the initial first, second, and third power flow solutions of the target node in the current second iteration are fitted to obtain the fitted curve in the current second iteration. The extreme points and extreme values ​​of the fitted curve in the current second iteration are determined. The extreme points and extreme values ​​in the current second iteration are determined as the predicted power flow solution in the current second iteration. Based on the predicted power flow solution in the current second iteration, power flow calculation is performed to obtain the corrected power flow solution in the current second iteration. Based on the load in the corrected power flow solution under the current second iteration, determine whether the power flow has converged under the current second iteration, and obtain the fourth convergence judgment result under the current second iteration; If the fourth convergence judgment result in the current second iteration is convergence, then the corrected power flow solution in the current second iteration is determined as the second target corrected power flow solution; If the fourth convergence judgment result under the current second iteration round is non-convergence, then the initial second power flow solution, initial third power flow solution and initial load change step size under the current second iteration round are updated to the initial second power flow solution, initial third power flow solution and initial load change step size under the next second iteration round, and the function returns "Based on the voltage of each operating node in the UHV power grid under the initial first power flow solution under the current second iteration round and the voltage of each operating node under the initial third power flow solution, determine the target node under the current second iteration round", until the second target corrected power flow solution is obtained.

7. The ultra-high voltage power grid state optimization method according to claim 6, characterized in that, Based on the second objective corrected power flow solution, the corrected power flow solution is iterated multiple times in the third round by updating the load change step size until a preset critical point is reached, thus obtaining the third objective corrected power flow solution, including: The iterative process of the corrected power flow solution in any current third iteration includes: Obtain the initial second power flow solution, the initial third power flow solution, and the initial load change step size under the current third iteration; Based on the voltage of each operating node in the UHV power grid under the initial first power flow solution in the current third iteration round and the voltage of each operating node under the initial third power flow solution, the target node in the current third iteration round is determined. Using Newton's interpolation method, the initial first, second, and third power flow solutions of the target node in the current third iteration are fitted to obtain the fitted curve in the current third iteration. The extreme points and extreme values ​​of the fitted curve in the current third iteration are determined. The extreme points and extreme values ​​in the current third iteration are determined as the predicted power flow solution in the current third iteration. Based on the predicted power flow solution in the current third iteration, power flow calculation is performed to obtain the corrected power flow solution in the current third iteration. Based on the corrected power flow solution in the current third iteration, determine whether the preset critical point has been reached in the current third iteration, and obtain the fifth convergence judgment result in the current third iteration. If the fifth convergence judgment result under the current third iteration is convergence, then the corrected power flow solution under the current third iteration is determined as the third target corrected power flow solution; If the fifth convergence judgment result under the current third iteration is non-convergence, then the initial second power flow solution, initial third power flow solution, and initial load change step size under the current third iteration are updated to the initial second power flow solution, initial third power flow solution, and initial load change step size under the next third iteration, and the function returns "Based on the voltage of each operating node in the UHV power grid under the initial first power flow solution under the current third iteration and the voltage of each operating node under the initial third power flow solution, determine the target node under the current third iteration", until the third target corrected power flow solution is obtained.

8. A computer device, comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that the processor executes the computer program to implement the ultra-high voltage power grid state optimization method according to any one of claims 1-7.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the computer program implements the UHV power grid state optimization method according to any one of claims 1-7.

10. A computer program product, comprising a computer program, characterized in that, When executed by a processor, the computer program implements the UHV power grid state optimization method according to any one of claims 1-7.

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