A watershed water engineering group joint scheduling method based on structural dimension reduction

Abstract

The application discloses a kind of based on structural dimension reduction's watershed water engineering group joint scheduling method, it is related to water conservancy field.The influence degree between water engineering is analyzed by measured hydrological data, the strong and weak hydraulic relationship is defined, and complex watershed water engineering system is decomposed into parallel scheduling unit in group, and the group is relatively independent;With flood control section as group boundary, upstream group scheduling result is used as downstream group boundary input, realize indirect cooperation between each parallel unit, while retaining the overall flood control correlation and hydraulic coupling relationship of whole watershed, avoid dimension disaster and solution instability caused by direct coupling calculation between groups, realize the organic unification of local optimization and overall planning, guarantee the overall scientificity and reliability of watershed flood control scheduling.

Description

Technical Field

[0001] This invention relates to the field of water conservancy engineering, and in particular to a joint scheduling method for a group of water conservancy projects in a watershed based on structural dimensionality reduction. Background Technology

[0002] Reservoirs, sluice gates, and flood storage and detention areas, as core components of the basin flood control system, play an irreplaceable role in flood prevention and disaster reduction due to their powerful flood storage and regulation capabilities. With the construction and commissioning of numerous reservoirs and power stations, the basin water project scheduling model has gradually shifted from traditional independent operation of single reservoirs to collaborative scheduling of multiple projects. Joint flood control optimization scheduling of reservoirs, sluice gates, and flood storage and detention areas has become an important non-engineering flood control measure. This scheduling method, through the construction of mathematical models and the application of optimization algorithms, can achieve precise control of flood peak regulation and flood storage, effectively mitigating or even avoiding flood disasters, and meeting the needs for rapid response and precise control in practical applications of basin flood control.

[0003] Extensive research and numerous achievements have been made by scholars both domestically and internationally regarding the joint flood control scheduling problem of watershed water conservancy projects. Wasimi et al. constructed a linear programming model to solve the watershed flood control scheduling problem with the objective of minimizing flood losses; Yi Shuzhen et al. established a joint scheduling model for the parallel reservoirs in the Lishui River basin with the objective of minimizing and uniformly discharging the total flood discharge; Kelman et al. introduced a penalty function to optimize the flood control capacity allocation of the reservoir group in the Brazil River basin; Sheng Dong et al. took the reservoir group in the Xiaoshui River basin as an example, set hierarchical flood control objectives in the model, and solved the problem using the DP-PS algorithm. To further improve the computational efficiency of the model, scholars have proposed a variety of optimization strategies: Mingbo et al. replaced the traditional two-point linear interpolation with a piecewise linear function of the reservoir characteristic curve, which significantly shortened the computation time of the model without affecting the optimization accuracy and algorithm stability; Ji Changming et al. used parallel acceleration technology to realize GPU parallel computing of the algorithm through OpenACC, which improved the computational efficiency; Yao Yonggao established a reservoir group flood control scheduling model based on two strategies: selecting key flood control reservoirs and dividing the key scheduling period, which shortened the model computation time by 24% and 65%, respectively; Bao et al. established a complex relationship between reservoir discharge flow and flood loss through machine learning methods, which improved the model solution efficiency while ensuring the computational accuracy.

[0004] Current research still has significant shortcomings: Most watershed water projects are complex and interconnected, making it difficult for traditional scheduling models to fully leverage the collaborative flood control effectiveness of multiple projects; most scheduling models and optimization algorithms are too time-consuming to solve, failing to adapt to real-time flood control scheduling scenarios and thus unable to meet the core needs of rapid response and precise control in actual watershed flood control operations. Existing efficiency optimization strategies are mostly targeted at single types of water projects or specific scenarios, lacking versatility and failing to address the efficiency bottleneck of joint scheduling under complex interconnected systems. They also cannot provide efficient and reliable technical support for the engineering application of joint optimization scheduling for flood control of watershed water project groups. Summary of the Invention

[0005] To address the aforementioned issues, this invention provides a joint scheduling method for watershed water conservancy projects based on structural dimensionality reduction. This method improves model solution efficiency while ensuring scheduling accuracy, specifically solving the problems of long solution time and difficulty in real-time operation of traditional models. It provides scientific support for the engineering application of joint optimization scheduling for flood control in watershed water conservancy projects.

[0006] This invention is implemented as follows:

[0007] It includes two aspects, the first aspect:

[0008] A joint scheduling method for watershed water conservancy projects based on structure dimensionality reduction includes the following steps:

[0009] Collect and organize basic watershed data, including basic water engineering data, hydrological time series data, and flood evolution-related parameters, to ensure data consistency in time series and perform preprocessing.

[0010] Based on the interval flood process, coupled with the outflow of water projects and combined with the measured flow data of key flood control sections in the basin, a joint flood control scheduling model of the basin's water project group is constructed to simulate the water level and flow changes of water projects and downstream control sections under the combined effect of flood and engineering scheduling. The model takes the reduction of the peak flood flow of the downstream section to the greatest extent while ensuring the safety of water projects as the objective function, and sets constraints, including water level constraints, flow constraints, water balance constraints, hydraulic relationship constraints, outflow amplitude constraints, and non-negativity constraints.

[0011] By analyzing measured hydrological data, we can determine the extent to which changes in the discharge of upstream water projects affect the inflow and water level of downstream water projects, and clarify the relative strengths of hydraulic influences between water projects.

[0012] Using the main stream of the river as the natural network, the approved flood control sections, hydrological station sections and river flood control nodes within the basin are selected as the boundaries between groups. Water projects with strong hydraulic impact are grouped into the same parallel scheduling unit to ensure that the projects within the group are closely related to hydraulics and have strong scheduling coordination.

[0013] Each parallel scheduling unit dynamically configures optimization objectives based on the actual scheduling needs of the basin; key reservoirs with large flood control capacity and outstanding regulation capabilities are set as core scheduling decision variables within the unit; the control rules of downstream supporting non-core projects are uniformly incorporated into the model constraints for overall consideration, and the model solution dimensionality is reduced by simplifying optimization variables and solidifying the control boundaries of auxiliary projects, thereby reducing the computational complexity of the model.

[0014] Indirect coordination is achieved between parallel scheduling units through the transmission of hydrological data at control sections, with the scheduling results of the upstream unit serving as the boundary input for the downstream unit. Using the flood control sections downstream of each parallel scheduling unit as the inter-unit coupling and transmission nodes, the downstream unit's discharge flow process, after flood evolution calculation using the Muskingan method, serves as the interval flood input boundary for the downstream unit. Scheduling solutions are sequentially performed on each parallel scheduling unit from upstream to downstream according to the direction of the basin flood evolution. After the upstream unit completes its solution, it transmits the discharge flow results to the downstream unit, which then performs its solution based on the updated boundary conditions, thus achieving temporal coordination between units.

[0015] Furthermore, the aforementioned interval flood refers to the flow generated between the water project and the downstream flood control section. Combining the outflow from the water project and the measured flow at the control section, the calculation formula is derived through the Muskingan method as follows:

[0016]

[0017] In the formula, For water engineering The flood process between the downstream flood control section and the downstream flood control section; The downstream flood control section Flow rate at any given moment; , , For flood evolution coefficient, ;

[0018] The Muskingan method uses a 1-hour time step to maintain consistency with the accuracy of watershed hydrological time series data and the data acquisition interval for real-time monitoring of water conservancy projects; the length of the river segment is set according to the stability requirements of the calculation parameters and does not exceed 10km.

[0019] Furthermore, the formula for calculating the objective function is as follows:

[0020]

[0021] In the formula, Q represents the optimal peak flood discharge for downstream flood control sections. Let T be the flow rate at the downstream flood control section during time period t, and T be the total number of scheduling periods.

[0022] Furthermore, the water level constraint is specifically as follows:

[0023] Water level constraints: During the scheduling process, the water level of the water project must be controlled within the allowable range to avoid the water level being too low and exceeding the lower limit of the project's operation, and to prevent the water level from being too high and exceeding the safety control threshold. This ensures the structural safety and operational stability of the water project itself and requires the following formula to be met:

[0024]

[0025] In the formula, , Water projects The minimum and maximum water levels that are allowed to be reached during the scheduling process; For water engineering At the end of the scheduling period, the first The actual water level during the period; The preset target water level at the end of the water project period;

[0026] Flow constraints include constraints on the discharge capacity of water projects, the safe discharge capacity of downstream river channels, and the safe flow constraints at control sections. The calculation formulas are as follows:

[0027]

[0028]

[0029]

[0030] In the formula, Let be the discharge flow rate of the i-th water project at time t. For water engineering Maximum discharge capacity Let t be the flow rate at the j-th downstream flood control control section at time t; For water engineering The safe discharge capacity of the downstream river channel; The safe flood discharge flow rate for the j-th control section downstream;

[0031] Water balance constraint: Ensures water conservation during scheduling; the calculation formula is as follows:

[0032]

[0033] in, For water engineering The water storage volume at time t; Water projects Inflow rate during time period t; Water projects Outflow rate during time period t; To calculate the time step;

[0034] Hydraulic constraints: The functional relationships between water level and reservoir capacity, and between water level and discharge capacity, must satisfy the water level-reservoir capacity curve and the water level-discharge capacity curve, respectively. The calculation formulas are as follows:

[0035]

[0036]

[0037] In the formula, For water engineering The water storage at time t, For water engineering The water surface elevation at time t; For water engineering Water level-reservoir capacity relationship function; For water engineering The water level-discharge capacity relationship function;

[0038] Outflow rate variation constraint: To avoid frequent opening and closing of the gate, the change in outflow rate between adjacent time periods must be controlled within the allowable range. The calculation formula is as follows:

[0039]

[0040] In the formula, For water engineering The maximum allowable flow rate variation within adjacent time periods;

[0041] Non-negativity constraint: Water level, reservoir capacity, and flow rate variables are all non-negative values.

[0042] Furthermore, the relative strengths of hydraulic influences among water conservancy projects are determined through hydraulic influence weighting, and the calculation formula is as follows:

[0043]

[0044] In the formula, The weight of the hydraulic influence of upstream water project i on downstream water project j; The upstream water project is lagging behind Outbound flow rate during a given time period, m 3 / s, The flood evolution time lag is represented by K, which is the river flow propagation coefficient. ; Let be the inflow rate of the downstream water project j at time t.

[0045] Furthermore, the criteria for classifying the strong and weak relationships are as follows: a hydraulic influence weight of 0 to 0.2 indicates a weak hydraulic influence, 0.2 to 0.6 indicates a medium hydraulic influence, and 0.6 to 1.0 indicates a strong hydraulic influence.

[0046] Furthermore, the method also includes a verification and adjustment mechanism. Using the hydraulic influence weights among water projects within a parallel scheduling unit group as the core indicator, the unit group is verified based on specific hydraulic response conditions. The verification includes verification of the hydraulic correlation within the group, the validity of the boundary between groups, and the scheduling complexity and efficiency. For items that fail the verification, corresponding adjustments are implemented based on the actual situation of the basin. After all adjustments are completed, verification is repeated until all verification indicators meet the standards. After the initial verification, regular or irregular review verifications are conducted based on changes in the basin's hydrological situation, water project modifications, and extreme flood events, forming a closed-loop management system of division-verification-adjustment-re-verification. Records related to verification and adjustment are retained to ensure traceability and reproducibility.

[0047] Furthermore, the verification of the hydraulic correlation within the group specifically involves: using the hydraulic influence weights between water projects within the unit group as the core indicator, and combining the following two hydraulic response scenarios to comprehensively determine strong hydraulic correlation in order to verify the correlation within the group;

[0048] Upstream and downstream conditions of the main stream: If the flood control capacity of the upstream core project accounts for ≥30% of the total flood control capacity of the downstream, it is determined to be a strong hydraulic impact;

[0049] Adjacent tributary situation: If the sum of the flood control capacity of the core projects of the tributaries accounts for ≥50% of the total flood control capacity downstream of the confluence section, it is judged as a strong hydraulic impact;

[0050] By using model simulation calculations, combined with the above-mentioned situations and hydraulic influence weighting indicators, it is determined whether the hydraulic correlation of water projects within the group is close. If the correlation does not meet expectations, it is judged as not meeting the standard.

[0051] The beneficial effects of this invention are: by analyzing the degree of influence between water projects through measured hydrological data and clarifying the strong and weak hydraulic relationships, this invention groups and divides the complex watershed water engineering system into parallel scheduling units that are closely related within the group and relatively independent between the groups, effectively solving the problem of modeling difficulties in high-dimensional hybrid systems and improving the adaptability and modeling accuracy of complex water engineering layouts.

[0052] By decomposing the entire watershed system into multiple relatively independent parallel units, the dimensionality of decision variables and the computational scale of a single scheduling model are reduced. Compared with the traditional whole-watershed coupled optimization solution method, the amount of computation and solution time are greatly reduced. The optimized scheduling strategies of each unit can be generated quickly, which is suitable for the timeliness requirements of rapid response and precise control in flood control scheduling scenarios, and provides efficient technical support for real-time flood control decision-making.

[0053] Using the flood control section as the boundary between groups and the upstream group scheduling result as the downstream group boundary input, the indirect coordination of each parallel unit is realized. While preserving the overall flood control correlation and hydraulic coupling relationship of the whole basin, the dimensionality curse and solution instability caused by direct coupling calculation between groups are avoided. This achieves the organic unity of local optimization and global planning, ensuring the overall scientificity and reliability of the basin flood control scheduling.

[0054] Based on actual hydrological and hydraulic relationships, the structured dimensionality reduction method does not rely on fixed engineering layouts or parameters of specific watersheds. It has good universality and can be flexibly applied to joint scheduling scenarios of watershed water engineering groups of different scales and layouts. It reduces the implementation and promotion costs of complex scheduling models in practical engineering applications and has significant engineering application value.

[0055] The present invention will be explained in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0056] Figure 1 This is a flowchart of the joint scheduling method for watershed water engineering groups based on structural dimensionality reduction according to the present invention.

[0057] Figure 2 A schematic diagram of the joint scheduling of a watershed water engineering group based on structure dimensionality reduction;

[0058] Figure 3 The results are from a simulation comparison of the joint scheduling of water conservancy projects in the basin. Detailed Implementation

[0059] Example 1:

[0060] This embodiment presents a joint scheduling method for watershed water conservancy projects based on structural dimensionality reduction. It models and reduces the structural dimensionality of existing topological connectivity relationships within the watershed's water conservancy projects. These topological relationships represent the existing project layout and do not require reconstruction in this invention. Figure 1 As shown, it includes the following steps:

[0061] Step S1, Data Acquisition and Preprocessing:

[0062] Systematically collect core data on water conservancy projects and flood control sections within the basin, ensuring data integrity and accuracy, specifically including:

[0063] (1) Basic parameters of water conservancy projects: flood control limit water level, maximum allowable water level, minimum operating water level, total storage capacity, water level-storage capacity curve, water level-discharge capacity curve, maximum discharge capacity, safe discharge capacity of downstream river channel, safe flood discharge flow of flood control section and other engineering characteristic parameters of each reservoir / sluice gate / flood storage area;

[0064] (2) Hydrological time series data: hourly inflow, outflow and real-time water level of each water project during the scheduling period, and hourly measured flow and water level of each flood control section;

[0065] (3) Flood evolution parameters: flood evolution coefficients (C0, C1, C2) required by the Muskingan method;

[0066] Preprocessing methods:

[0067] (1) Rationality verification: Based on the operational boundary of the water project, obvious abnormal values ​​such as water level exceeding the engineering design range and negative flow are eliminated;

[0068] (2) Outlier handling: adopt The criteria identify outliers. For missing data in hydrological time series, linear interpolation is performed using measured data from adjacent time points. The missing values ​​are fitted using the linear relationship between flow and water level between the two points to complete the data.

[0069] Step S2, Construction of the joint flood control scheduling model:

[0070] Based on the inter-regional flood process, this study couples the outflow from water projects such as reservoirs and sluices, and combines measured flow rates at key flood control sections to complete parameter calibration and model verification, thus constructing a joint flood control scheduling model for a group of water conservancy projects in the basin. The model takes natural floods and inter-regional flood processes as inputs, and its core output is the dynamic process of water level and flow at water projects and downstream control sections, providing quantitative simulation support for the coordinated and unitized joint flood control scheduling of water projects.

[0071] Inter-regional floods are runoff generated between a water project and its downstream flood control section. They require calculation using the Muskingan method, combining the outflow from the water project and the measured flow at the control section. The calculation formula is as follows:

[0072]

[0073] In the formula, For water engineering The interval flood process between the downstream flood control section and the downstream flood control section, m 3 / s; The downstream flood control section Flow rate at any given moment, m 3 / s; , , For flood evolution coefficient, .

[0074] The Muskingan method uses a 1-hour time step to maintain consistency with the accuracy of watershed hydrological time series data and the data acquisition interval of real-time monitoring of water conservancy projects. The length of the river segment is set according to the stability requirements of the calculation parameters, usually not exceeding 10km. In practical applications, it can be flexibly adjusted according to the river topography, hydraulic characteristics and calculation accuracy requirements.

[0075] Step S3, optimize the objective and constraints:

[0076] 1. Model objective function:

[0077] The model's core objective is to ensure the safety of the water project itself and minimize the peak flood flow at the downstream control section. Therefore, in the event of a flood, the scheduling objective can be set as follows: while ensuring the safety of the water project itself, the peak flood flow at the downstream flood control section should be as small as possible, thereby minimizing the downstream flood control pressure. The objective function is shown in the following equation:

[0078]

[0079] In the formula, Q represents the optimal peak flood discharge for downstream flood control sections. Let T be the flow rate at the downstream flood control section during time period t, and T be the total number of scheduling periods.

[0080] 2. Model constraint setting:

[0081] 1) Water level constraint:

[0082] During the scheduling process, the water level of the water project must be controlled within the allowable range. This means preventing the water level from falling too low and exceeding the project's lower operating limit, while also preventing it from rising too high and breaching safety control thresholds. This ensures the structural safety and operational stability of the water project itself, and requires meeting the following formula:

[0083]

[0084] In the formula, , Water projects The minimum and maximum water levels allowed to be reached during the scheduling process, in meters (m); For water engineering At the end of the scheduling period (the first The actual water level (in meters) during the specified time period. The target water level at the end of the water project period is set in meters.

[0085] 2) Flow constraints:

[0086] This includes constraints on the discharge capacity of water projects, the safe discharge capacity of downstream river channels, and the safe flow constraints at control sections. The calculation formulas are as follows:

[0087]

[0088]

[0089]

[0090] In the formula, Let be the discharge flow rate of the i-th water project at time t. For water engineering Maximum discharge capacity Let t be the flow rate at the j-th downstream flood control control section at time t; For water engineering The safe discharge capacity of the downstream river channel; The safe flood discharge capacity is defined as the j-th control section downstream. All parameters mentioned above are in meters (m³). 3 / s.

[0091] In the formula, , Water projects Maximum discharge capacity, downstream of the water project The flow rate at time t at each control section, m 3 / s; , Water projects The safe discharge capacity of the downstream river channel and the safe flood discharge capacity of the downstream flood control section, m 3 / s.

[0092] 3) Water balance constraints:

[0093] To ensure water conservation during the scheduling process, the calculation formula is as follows:

[0094]

[0095] in, For water engineering The water storage volume at time t; Water projects Inflow rate during time period t; Water projects Outflow rate during time period t; To calculate the time step;

[0096] 4) Hydraulic constraints:

[0097] The functional relationships between water level and reservoir capacity, and between water level and discharge capacity, must satisfy the water level-reservoir capacity curve and the water level-discharge capacity curve, respectively. The calculation formulas are as follows:

[0098]

[0099]

[0100] In the formula, For water engineering The water storage at time t, For water engineering The water surface elevation at time t; For water engineering Water level-reservoir capacity relationship function; For water engineering The water level-discharge capacity relationship function.

[0101] 5) Constraints on outbound flow rate variation:

[0102] To avoid frequent opening and closing of the gates, the change in outflow rate between adjacent time periods must be controlled within the allowable range. The calculation formula is as follows:

[0103]

[0104] In the formula, For water engineering The maximum allowable flow rate variation within adjacent time periods, m 3 / s.

[0105] 6) Nonnegativity constraint

[0106] Variables such as water level, reservoir capacity, and flow rate are all non-negative.

[0107] Step S4, structural dimensionality reduction:

[0108] During flood control scheduling, water gates are not opened and closed frequently, but are typically adjusted every 4-6 hours when necessary. To reflect the actual scheduling process and accelerate the model's solution rate, the model's decision-making period is set to 4 hours. By simplifying the number of time periods, the computational load is reduced. The specific processing steps are as follows.

[0109] 1) The hourly reservoir inflow process and the interval flood process are averaged over 4 hours to obtain the model input data for T / 4 decision periods;

[0110] 2) After solving the model, the outbound flow process obtained in T / 4 decision periods is interpolated and extended to an outbound flow process in T periods;

[0111] 3) Combining the reservoir inflow process and the interval flood process in T time periods, the hourly reservoir water level, reservoir capacity change process and flow process at the downstream control section are recalculated using the water balance principle.

[0112] For complex hybrid systems consisting of multiple water projects, the core scheduling challenge lies in the intricate series and parallel relationships between these projects. This necessitates simultaneously handling multi-dimensional hydraulic coupling constraints and a large number of decision variables. Consequently, each iteration of the model requires traversing the coupling relationships of all water projects, resulting in an exponential increase in computational complexity, making it difficult to meet real-time scheduling requirements. To address this common problem in the scheduling of hybrid water projects, a "grouping and collaboration" structural dimensionality reduction approach is adopted, as detailed below:

[0113] 4.1 Clarify the relative strengths of hydraulic influences among water projects:

[0114] By analyzing measured hydrological data, we can determine the extent to which changes in the discharge of upstream water projects affect the inflow and water level of downstream water projects, and clarify the relative strengths of hydraulic influences between water projects.

[0115] Hydraulic correlation analysis: The inflow of downstream water projects consists of "the discharge of upstream water projects + the inter-regional flood". The higher the proportion of upstream discharge to downstream inflow, the stronger its hydraulic control effect and the closer the connection. The formula for determining the strength of the hydraulic correlation between water projects is as follows:

[0116]

[0117] In the formula, The weight of the hydraulic influence of upstream water project i on downstream water project j; The upstream water project is lagging behind Outbound flow rate during a given time period, m 3 / s, ( (where K is the river flow propagation coefficient, representing the flood evolution time lag). ; Let be the inflow rate of the downstream water project j at time t.

[0118] Quantitative assessment of impact: Weighting the hydraulic impact of upstream water projects on downstream water projects. Quantify the impact of upstream discharge on downstream water projects and clarify the strength of hydraulic connections between water projects. The closer to 1, the more the inflow of downstream water project j depends on the outflow of upstream water project i, and the stronger the hydraulic correlation; the closer to 0, the weaker the correlation.

[0119] Clearly defined strength relationships: Based on quantitative assessment results, the strength ranges of hydraulic influence are divided, the priority of the impact of different upstream water projects on different downstream water projects is clarified, and a grading standard for the strength of hydraulic correlations is established based on engineering experience: hydraulic influence weight. Values ​​of 0-0.2 represent weak hydraulic influence, 0.2-0.6 represent moderate hydraulic influence, and 0.6-1.0 represent strong hydraulic influence. Priority is given to marking water project association pairs with high impact and short response time delays, distinguishing between core impact sources (strongly impacting upstream projects) and secondary impact sources (weakly impacting upstream projects), and forming a list of the strong and weak relationships of hydraulic influence among water projects.

[0120] 4.2 Water Engineering Grouping:

[0121] Using the main stream of the river as its natural network, approved flood control sections, hydrological station sections, and river flood control nodes within the basin are selected as inter-group boundaries. Water projects with significant hydraulic impact (strong hydraulic impact) are grouped into the same parallel dispatch unit to ensure close hydraulic connections and strong dispatch coordination among projects within the group. For example... Figure 2 As shown, Reservoir 1 and Reservoir 2 are connected in parallel, and the two are connected in series with Reservoir 3. The three have a significant hydraulic influence. Reservoir 3 is set as the boundary between groups, and Reservoir 1 and Reservoir 2 are divided into the same parallel scheduling unit.

[0122] 4.3 Simplification of Coordination Logic within Parallel Scheduling Unit Groups:

[0123] The unit partitioning logic relies on the inherent topological layout and hydraulic coupling characteristics of the project, and dynamically configures optimization objectives according to the actual scheduling needs of the basin. It can select to reduce the peak flow at downstream flood control sections, or, based on the multi-objective coordination requirements of flood control scheduling, superimpose core flood control optimization objectives such as minimizing flood diversion and maximizing remaining flood control capacity. It can also be compatible with and expand objectives such as water supply security, maximizing power generation benefits, and ensuring navigation water levels. The addition, subtraction, replacement, weight adjustment, and priority configuration of the above scheduling objectives are all directly implemented within the constructed dimensionality-reduced scheduling unit group, without the need for re-constructing the topology and partitioning the units, thus improving the versatility, adaptability, and execution efficiency of the joint scheduling of the water project group.

[0124] For example, each parallel scheduling unit takes reducing the peak flow of its downstream flood control section as its core scheduling objective, and sets the backbone reservoirs with large flood control capacity and outstanding regulation capabilities as the core scheduling decision variables within the unit; the control rules of downstream supporting sluice gates, flood storage and detention areas and other non-core projects are uniformly incorporated into the model constraints for overall consideration, and the model solution dimensionality is reduced by simplifying and optimizing variables and solidifying the control boundaries of auxiliary projects, which effectively reduces the computational complexity of the unit model.

[0125] 4.4 Indirect Coordination Between Parallel Scheduling Units:

[0126] Parallel scheduling units achieve indirect coordination through the transmission of hydrological data at control sections. The scheduling results of the upstream group serve as the boundary input for the downstream group, thus preserving the overall flood control correlation of the system while avoiding direct coupling calculations between groups.

[0127] Using the flood control sections downstream of each parallel dispatching unit as inter-group coupling and transmission nodes, the downstream discharge flow process of the upstream unit is calculated using the Muskingan method to complete the flood evolution calculation, and then used as the interval flood input boundary of the downstream unit. According to the direction of the basin flood evolution, the dispatching solution is carried out for each parallel dispatching unit from upstream to downstream. After the upstream unit completes the solution, it immediately transmits the discharge flow result to the downstream unit. The downstream unit carries out the solution based on the updated boundary conditions, thereby realizing the temporal coordination between units.

[0128] Step S5, Verification and Adjustment Mechanism:

[0129] The verification of the dimensionality reduction requirements—strong coupling within the verification unit group and relative independence between groups—ensures that the grouping can support subsequent scheduling calculations. This mainly includes three core verifications:

[0130] 5.1 Verification:

[0131] 5.1.1 Verification of hydraulic correlation tightness within the group:

[0132] Hydraulic influence weights among water works within a unit group As the core indicator, the following specific hydraulic response scenarios will be combined to comprehensively determine strong hydraulic correlations and verify the tightness of intragroup correlations:

[0133] (1) Situation of upstream and downstream of the main stream: If the flood control capacity of the upstream core project accounts for ≥30% of the total flood control capacity of the downstream, it is determined to be a strong hydraulic impact;

[0134] (2) Adjacent tributary situation: If the sum of the flood control capacity of the core projects of the tributary accounts for ≥50% of the total flood control capacity downstream of the confluence section, it is determined to be a strong hydraulic impact.

[0135] Through model simulation calculations, combined with the above situations and The indicator is used to determine whether the hydraulic connections between water projects within a group are close. If the degree of connection does not meet expectations, it is judged as failing to meet the standard.

[0136] 5.1.2 Validation of inter-group boundaries:

[0137] Taking the inter-group flood control section as the core, the isolation effect of the boundary on the hydraulic interference between groups and the feasibility of inter-group coordination are verified. Through independent scheduling and joint scheduling simulation of the whole basin, it is verified whether the boundary can achieve effective isolation and coordination. If either effect fails to meet the standard, the boundary is judged to be invalid.

[0138] 5.1.3 Scheduling Complexity and Efficiency Verification:

[0139] Verify the solution efficiency and convergence of the grouped model, compare the model calculation results before and after grouping, and verify whether the dimensionality reduction objective has been achieved. If the calculation efficiency has not improved or the model cannot converge stably, it is judged as unsatisfactory.

[0140] 5.2 Adjustment Mechanism:

[0141] For items that fail the verification, adjustments are made based on the actual situation of the watershed: if the intra-group correlation is not up to standard, the correlation is improved by splitting and reorganizing the unit groups; if the inter-group boundary is not up to standard, the boundary delineation or constraint conditions are optimized to ensure the independence and coordination between groups; if the scheduling efficiency is not up to standard, the unit size is simplified, the constraints are simplified, or the algorithm is optimized.

[0142] After all adjustments are completed, re-verification is required until all standards are met. After the initial verification, regular reviews should be conducted in conjunction with changes in the watershed and engineering projects to form a closed loop of division-verification-adjustment-reverification, with relevant records retained to ensure traceability and reproducibility.

[0143] After the structural dimensionality reduction method of this invention is verified and adjusted, a low-dimensional joint scheduling model of water conservancy projects that meets the accuracy requirements of flood control scheduling can be obtained. Based on this model, the flood control scheduling of the basin can be directly calculated, and the scheduling results such as water conservancy project flow, water level process and downstream control section flood process can be output to guide the actual flood control scheduling work of the basin.

[0144] This invention analyzes the hydraulic impact of a watershed water conservancy project group and reduces its structural dimensions to form closely related but relatively independent parallel scheduling units. It achieves indirect coordination between groups through control sections. While preserving the overall flood control correlation, it avoids direct coupling calculation of the entire system. This fundamentally solves the technical problems of traditional scheduling modes, such as the inability to fully utilize the flood control effectiveness of multi-project collaboration, the excessive time required to solve scheduling models to meet real-time scheduling needs, and the poor universality of existing optimization strategies. It realizes rapid response, precise control, and engineering application of joint scheduling of complex mixed water conservancy project groups.

[0145] Example 2:

[0146] This embodiment presents an example of a joint scheduling method for watershed water conservancy projects based on structure dimensionality reduction. A watershed water conservancy project group is selected as the research object to conduct analysis and verify the feasibility and practicality of the joint scheduling method based on structure dimensionality reduction. The spatial distribution of the water conservancy projects is as follows: Figure 2 As shown, the calculation results of the joint scheduling example of the water project group are summarized in Table 1. Figure 3 .

[0147] This study set up two comparison schemes, B1 and B2, as control variables to eliminate the interference of boundary condition differences on scheduling results. The two schemes adopted completely consistent joint scheduling boundary constraints. The specific parameters are detailed in Table 2.

[0148] Table 1. Calculation results of a joint operation example of a water conservancy project group in a certain river basin.

[0149]

[0150] Table 2 Joint Scheduling Boundary Conditions

[0151]

[0152] Among them, Scheme B1 uses 4 hours as a decision period for joint scheduling of water engineering groups, while Scheme B2 adopts structural dimensionality reduction based on Scheme B1, transforming the complex hybrid system into two sets of parallel scheduling units.

[0153] The upstream group (Reservoirs 1 and 2) will conduct joint scheduling with Reservoir 3 as the control section, aiming to minimize the maximum peak reduction and the maximum three-day flood volume at this control section. The downstream group (Reservoirs 3 and 4) will conduct joint scheduling with the goal of maximizing the peak reduction at control section 2.

[0154] Depend on Figure 3 The calculation results show that the flow process at control section 2 is basically consistent in the reservoir scheduling process of the two schemes. The main difference lies in the inflow process of reservoir 3. This is because scheme B2 avoids the situation of "peak-to-peak" encounter between inter-regional flood and reservoir discharge through the coordinated interception of reservoir 1 and reservoir 2, which verifies the optimization effect of joint scheduling of water projects on the coordinated peak staggering of upstream reservoirs.

[0155] As can be seen from the statistical results in Table 1, the calculation time of scheme B1 is 348s, and the simulated peak flow of control section 2 is 4015m³ / s; scheme B2, based on B1, superimposes structural dimensionality reduction, and the calculation time is further reduced to 182s. Compared with B1, the model calculation rate is improved by 48%, and the simulated peak flow of control section 2 is 3955m³ / s, with a deviation of only 60m³ / s from scheme B1, and the deviation rate is less than 1.5%.

[0156] This result fully demonstrates that the joint scheduling method for watershed water conservancy projects based on structure reduction can significantly reduce computational load and effectively improve the solution efficiency of the joint optimization scheduling model for flood control of water conservancy projects by simplifying system coupling relationships while ensuring scheduling accuracy. In summary, the joint scheduling method for watershed water conservancy projects based on structure reduction proposed in this invention is successful and feasible.

[0157] The above description is only used to illustrate the technical solutions of the present invention and is not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention (such as the application of various formulas, the order of steps, etc.) without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A joint scheduling method for a watershed water conservancy project group based on structural dimensionality reduction, characterized in that, Includes the following: Collect and organize basic watershed data, including basic water engineering data, hydrological time series data, and flood evolution-related parameters, to ensure data consistency in time series and perform preprocessing. Based on the interval flood process, coupled with the outflow of water projects and combined with the measured flow data of key flood control sections in the basin, a joint flood control scheduling model of the basin's water project group is constructed to simulate the water level and flow changes of water projects and downstream control sections under the combined effect of flood and engineering scheduling. The model takes the reduction of the peak flood flow of the downstream section to the greatest extent while ensuring the safety of water projects as the objective function, and sets constraints, including water level constraints, flow constraints, water balance constraints, hydraulic relationship constraints, outflow amplitude constraints, and non-negativity constraints. By analyzing measured hydrological data, we can determine the extent to which changes in the discharge of upstream water projects affect the inflow and water level of downstream water projects, and clarify the relative strengths of hydraulic influences between water projects. Using the main stream of the river as the natural network, the approved flood control sections, hydrological station sections and river flood control nodes within the basin are selected as the boundaries between groups. Water projects with strong hydraulic impact are grouped into the same parallel scheduling unit to ensure that the projects within the group are closely related to hydraulics and have strong scheduling coordination. Each parallel dispatching unit dynamically configures and optimizes targets based on the actual dispatching needs of the basin; key reservoirs with large flood control capacity and outstanding regulation capabilities are set as core dispatching decision variables within the unit; The management rules for downstream non-core supporting projects are uniformly incorporated into the model constraints for overall consideration. By simplifying and optimizing variables and solidifying the management boundaries of ancillary projects, the model solution is reduced in dimensionality, thereby reducing the computational complexity of the model. Indirect coordination is achieved between parallel scheduling units through the transmission of hydrological data at control sections, with the scheduling results of the upstream unit serving as the boundary input for the downstream unit. Using the flood control sections downstream of each parallel scheduling unit as the inter-unit coupling and transmission nodes, the downstream unit's discharge flow process, after flood evolution calculation using the Muskingan method, serves as the interval flood input boundary for the downstream unit. Scheduling solutions are sequentially performed on each parallel scheduling unit from upstream to downstream according to the direction of the basin flood evolution. After the upstream unit completes its solution, it transmits the discharge flow results to the downstream unit, which then performs its solution based on the updated boundary conditions, thus achieving temporal coordination between units.

2. The method for joint scheduling of watershed water conservancy projects based on structural dimensionality reduction according to claim 1, characterized in that, The interval flood refers to the runoff generated between the water project and the downstream flood control section. The calculation formula is derived by combining the outflow from the water project and the measured flow at the control section, using the Muskingan method: In the formula, For water engineering The flood process between the downstream flood control section and the downstream flood control section; The downstream flood control section Flow rate at any given moment; , , For flood evolution coefficient, .

3. The method for joint scheduling of watershed water conservancy projects based on structural dimensionality reduction according to claim 1, characterized in that, The objective function is calculated using the following formula: In the formula, Q represents the optimal peak flood discharge for downstream flood control sections. Let T be the flow rate at the downstream flood control section during time period t, and T be the total number of scheduling periods.

4. The method for joint scheduling of watershed water conservancy projects based on structural dimensionality reduction according to claim 1, characterized in that, The water level constraint is specifically as follows: Water level constraints: During the scheduling process, the water level of the water project must be controlled within the allowable range to avoid the water level being too low and exceeding the lower limit of the project's operation, and to prevent the water level from being too high and exceeding the safety control threshold. This ensures the structural safety and operational stability of the water project itself and requires the following formula to be met: In the formula, , Water projects The minimum and maximum water levels that are allowed to be reached during the scheduling process; For water engineering At the end of the scheduling period, the first The actual water level during the period; The preset target water level at the end of the water project period; Flow constraints include constraints on the discharge capacity of water projects, the safe discharge capacity of downstream river channels, and the safe flow constraints at control sections. The calculation formulas are as follows: In the formula, Let be the discharge flow rate of the i-th water project at time t. For water engineering Maximum discharge capacity Let t be the flow rate at the j-th downstream flood control control section at time t; For water engineering The safe discharge capacity of the downstream river channel; The safe flood discharge flow rate for the j-th control section downstream; Water balance constraint: Ensures water conservation during scheduling; the calculation formula is as follows: in, For water engineering The water storage volume at time t; Water projects Inflow rate during time period t; Water projects Outflow rate during time period t; To calculate the time step; Hydraulic constraints: The functional relationships between water level and reservoir capacity, and between water level and discharge capacity, must satisfy the water level-reservoir capacity curve and the water level-discharge capacity curve, respectively. The calculation formulas are as follows: In the formula, For water engineering The water storage at time t, For water engineering The water surface elevation at time t; For water engineering Water level-reservoir capacity relationship function; For water engineering The water level-discharge capacity relationship function; Outflow rate variation constraint: To avoid frequent opening and closing of the gate, the change in outflow rate between adjacent time periods must be controlled within the allowable range. The calculation formula is as follows: In the formula, For water engineering The maximum allowable flow rate variation within adjacent time periods; Non-negativity constraint: Water level, reservoir capacity, and flow rate variables are all non-negative values.

5. The method for joint scheduling of watershed water conservancy projects based on structural dimensionality reduction according to claim 1, characterized in that, The relative strengths of hydraulic influences between water projects are clearly defined, and the calculation formula is as follows: (Hydraulic influence weighting is used to determine the relative strengths of these influences.) In the formula, The weight of the hydraulic influence of upstream water project i on downstream water project j; The upstream water project is lagging behind Outbound flow rate during a given time period, m 3 / s, The flood evolution time lag is represented by K, which is the river flow propagation coefficient. ; Let be the inflow rate of the downstream water project j at time t.

6. The method for joint scheduling of watershed water conservancy projects based on structural dimensionality reduction according to claim 5, characterized in that, The criteria for classifying the strength of the relationship are as follows: a hydraulic influence weight of 0 to 0.2 indicates a weak hydraulic influence, 0.2 to 0.6 indicates a medium hydraulic influence, and 0.6 to 1.0 indicates a strong hydraulic influence.

7. The method for joint scheduling of watershed water conservancy projects based on structural dimensionality reduction according to claim 1, characterized in that, The method also includes a verification and adjustment mechanism. Using the hydraulic influence weights among water projects within a parallel scheduling unit group as the core indicator, the unit group is verified based on specific hydraulic response conditions. The verification includes verification of the hydraulic correlation within the group, the validity of the boundary between groups, and the scheduling complexity and efficiency. For items that fail the verification, corresponding adjustments are implemented based on the actual situation of the basin. After all adjustments are completed, verification is repeated until all verification indicators meet the standards. After the initial verification, regular or irregular review verifications are conducted based on changes in the basin's hydrological situation, water project modifications, and extreme flood events, forming a closed-loop management system of division-verification-adjustment-re-verification. Records related to verification and adjustment are retained to ensure traceability and reproducibility.

8. The method for joint scheduling of watershed water conservancy projects based on structural dimensionality reduction according to claim 7, characterized in that, The verification of the hydraulic correlation within the group is specifically as follows: taking the hydraulic influence weight between each water project within the unit group as the core indicator, and combining the following two hydraulic response scenarios to comprehensively determine strong hydraulic correlation in order to verify the correlation within the group; Upstream and downstream conditions of the main stream: If the flood control capacity of the upstream core project accounts for ≥30% of the total flood control capacity of the downstream, it is determined to be a strong hydraulic impact; Adjacent tributary situation: If the sum of the flood control capacity of the core projects of the tributaries accounts for ≥50% of the total flood control capacity downstream of the confluence section, it is judged as a strong hydraulic impact; By using model simulation calculations, combined with the above-mentioned situations and hydraulic influence weighting indicators, it is determined whether the hydraulic correlation of water projects within the group is close. If the correlation does not meet expectations, it is judged as not meeting the standard.

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