Flood control dispatching simulation method and system suitable for multistage series-parallel cascade reservoirs

Abstract

The invention discloses a flood control scheduling simulation method and system suitable for multistage series-parallel cascade reservoirs. The method comprises the following steps: collecting and sorting basic data; extracting a river network water system, dividing sub-basins, generating a topological structure based on a cascade reservoir series-parallel connection relation, and performing standardization processing; on the basis of a cascade reservoir topological structure relation, a model is constructed based on a three-layer nested loop, and reservoir entering flood and flood regulation calculation process simulation of a cascade reservoir is realized step by step from upstream to downstream; by setting schemes, cascade reservoir flood control scheduling processes under different schemes are simulated, and scheme comparative analysis and effect evaluation are carried out. According to the method, the data base plate and the water and rain condition monitoring information are fully utilized, cascade reservoirs with complex series-parallel connection relations such as series connection, parallel connection or series-parallel connection can be adapted, cascade reservoir flood forecasting and flood control dispatching process simulation is achieved, reliable guarantee is provided for scientifically and reasonably formulating a cascade reservoir dispatching scheme, and the method is suitable for large-scale popularization and application. And a technical support is provided for improving flood control and disaster reduction capabilities.

Description

Technical Field

[0001] The present invention relates to the technical fields of reservoir flood control operation, cascade reservoir joint operation, and computational simulation technology, and particularly relates to a flood control operation simulation method and system suitable for multi-level series-parallel cascade reservoirs. Background Art

[0002] The joint operation of cascade reservoirs is an important measure to ensure the flood control safety management of the basin. The key lies in that through the joint operation of cascade reservoirs, excess flood or base flow can be regulated in different reservoirs as needed, improving the flood control standard of the flood control protection area and ensuring the flood control safety of key areas.

[0003] Currently, the common cascade reservoirs are series reservoir groups located on the same river, and there is a close hydraulic connection between the reservoirs. Parallel reservoir groups or complex cascade reservoirs with series-parallel combinations without direct hydraulic connection are relatively rare. In actual work, especially on small and medium-sized rivers, a large number of reservoirs located in the same water system with direct or indirect hydraulic connections can form cascade reservoirs. By regulating and controlling the storage and discharge of these cascade reservoirs, minimizing flood losses as much as possible is the key to the precise prevention and control of basin flood disasters. Therefore, based on the existing joint operation technology, effectively simulating the flood evolution and joint operation process of complex series-parallel cascade reservoirs and realizing the preview of flood control operation processes under different joint operation schemes are the key tasks in the prevention and control of basin flood disasters. Summary of the Invention

[0004] The purpose of the present invention is to provide a flood control operation simulation method and system suitable for multi-level series-parallel cascade reservoirs, which can effectively simulate the flood control operation process of multi-level series-parallel cascade reservoirs, provide a reliable guarantee for scientifically and reasonably formulating joint operation schemes, and provide technical support for improving the flood control and disaster reduction ability of the basin, so as to solve the problems raised in the above background art.

[0005] To achieve the above purpose, the present invention provides the following technical solutions:

[0006] A flood control operation simulation method suitable for multi-level series-parallel cascade reservoirs includes the following steps:

[0007] Step 1, collection and collation of basic data: Collect the basin basic data, reservoir basic data, reservoir flood control operation regulations, and water regime and rainfall monitoring station network information of the area to be simulated;

[0008] Step 2, generation and processing of the topological structure considering the series-parallel relationship of cascade reservoirs: Extract the river network water system based on the collected data, divide sub-basins, analyze the series-parallel relationship of cascade reservoirs, generate the topological structure of cascade reservoirs, and perform standardization processing;

[0009] Step 3, Simulation Method and Model Construction of Flood Control Operation for Cascade Reservoirs Based on Topological Structure: Combining the generated topological structure relationships of cascade reservoirs, calculate the sub-basin process, flood control operation, and river channel confluence respectively, and construct a model based on three-layer nested loops to simulate the inflow flood and flood regulation calculation process of cascade reservoirs step by step from upstream to downstream;

[0010] Step 4, Model Simulation and Scheme Evaluation: Set flood forecasting schemes and joint operation schemes, simulate the flood control operation process of cascade reservoirs under different schemes, and conduct scheme comparison analysis and effect evaluation in combination with the simulation results.

[0011] Furthermore, the basin basic data includes: the basin water system map containing rivers, lakes, and reservoirs, high-precision elevation data, and the basic data of rivers, lakes, and reservoirs; the reservoir basic data includes: reservoir characteristic water levels, characteristic storage capacities, water level-storage capacity curves, and water level-discharge curves; the water regime and rainfall monitoring station network information includes: the water regime and rainfall monitoring station network information including rain gauges, water level gauges, flow gauges, and hydrological stations and their measured data.

[0012] Furthermore, in Step 2, the generation and processing of the topological structure considering the series and parallel relationships of cascade reservoirs specifically include:

[0013] S201: River network water system extraction: Conduct hydrological analysis based on the high-precision elevation data and basin water system map of the basin to be simulated, divide the basic basins, and extract the river network consistent with the actual water system;

[0014] S202: Sub-basin division: According to the actual distribution positions of cascade reservoirs in the river network, merge the boundaries of basic basins and divide several sub-basins;

[0015] S203: Analysis of series and parallel relationships of cascade reservoirs: Based on the river network and sub-basin ranges, clarify the catchment areas of each reservoir, and identify the series and parallel relationships of cascade reservoirs according to the confluence relationships between upstream and downstream reservoirs;

[0016] S204: Topological structure generation: Based on the series and parallel relationships of cascade reservoirs, establish the association relationships with upstream and downstream reservoirs for each reservoir to form a preliminary topological structure, and assign calculation levels in the order from upstream to downstream;

[0017] S205: Standardization processing: Conduct data formatting processing on the preliminarily formed topological structure of cascade reservoirs, construct a topological relationship table, and store the standardized topological structure data in the database.

[0018] Furthermore, in Step 3: Simulation Method and Model Construction of Flood Control Operation for Cascade Reservoirs Based on Topological Structure, specifically include:

[0019] S301: Sub-basin flood process calculation method:

[0020] Based on the sub - watershed division results, combined with the flood forecasting scheme, a flood forecasting model is used to simulate the flood flow process of each sub - watershed. The calculation formula is as follows:

[0021]

[0022] In the formula, represents the simulated flow of the m - th sub - watershed, MODEL flood represents the flood forecasting model, represents the geographical characteristics of the m - th sub - watershed, represents the meteorological data within the m - th sub - watershed, β flood represents the parameters of the flood forecasting model;

[0023] If a certain sub - watershed completely covers the reservoir catchment area, the flow process at the outlet section of this sub - watershed is the flood inflow process of this reservoir; if a certain sub - watershed only covers a part of the reservoir catchment area, the flow process at the outlet section of this sub - watershed is the flood process of the corresponding catchment area of this reservoir.

[0024] S302: Flood control operation calculation method for independent reservoirs:

[0025] Based on the calculation result of the grade distribution, the independent reservoirs with a calculation grade of 1 in the topological structure of cascade reservoirs are extracted. For a certain independent reservoir, calculate the total inflow of the current independent reservoir, and combined with the set flood control operation scheme, use the reservoir flood routing calculation model to simulate the flood control operation process of the independent reservoir, and obtain the water level change process and the released flood process. The calculation formula is as follows:

[0026]

[0027] In the formula, j1 represents the j - th reservoir under the calculation grade 1, represents the total inflow of the j1 - th reservoir, represents the number of sub - watersheds corresponding to the j1 - th reservoir, represents the simulated flow of the sub - watershed where the j - th reservoir converges, represents the outflow of the j1 - th reservoir, MODEL operation represents the reservoir flood routing calculation model, represents the initial water level of the j1 - th reservoir, represents the water level - storage curve of the j1 - th reservoir, represents the water level - discharge curve of the j1 - th reservoir, represents the flood control operation scheme of the j1 - th reservoir;

[0028] S303: River confluence calculation method between upstream and downstream reservoirs:

[0029] Extract all reservoirs with a calculation level greater than 1 in the topological structure of cascade reservoirs based on the calculation level allocation results. For a certain reservoir at the current calculation level, obtain the flood discharge process of the upstream reservoir corresponding to the current reservoir. Use the river confluence calculation model to simulate the river confluence process from the dam of each upstream reservoir of the current reservoir to the dam of the current reservoir, and calculate the total inflow of the current reservoir. The calculation formula is as follows:

[0030]

[0031] In the formula, j k represents the j-th reservoir at the calculation level k, represents the number of upstream reservoirs of the j-th k reservoir, represents the total flood discharge of the upstream reservoirs reaching the j-th k reservoir, represents the flow rate reaching the j-th k reservoir after the flood discharge of the l-th upstream reservoir, MODEL routing represents the river confluence calculation model, represents the flood discharge of the l-th upstream reservoir, and respectively represent the river length and slope from the dam of the l-th upstream reservoir to the dam of the j-th k reservoir, β routing represents the parameter of the river confluence calculation model;

[0032] S304: Flood control operation calculation method for cascade reservoirs:

[0033] For a certain reservoir with a calculation level greater than 1, combine the set operation plan and the calculated total inflow, and use the reservoir flood regulation calculation model to simulate the flood control operation process of the current reservoir to obtain the water level change process and flood discharge process of the current reservoir. The calculation formula is as follows:

[0034]

[0035]

[0036] In the formula, j k represents the j-th reservoir at the calculation level k, represents the total inflow of the j-th k reservoir, represents the simulated flow rate in the catchment area of the j-th k reservoir, represents the outflow of the j-th k reservoir, represents the initial water level [m] of the j-th k reservoir, represents the j-thk The water level - storage capacity curve of the jth k reservoir's water level - discharge curve, indicating the flood control operation plan for the jth reservoir;

[0037] S305: Model construction based on three - layer nested loops:

[0038] Through the calculation of level loop, reservoir traversal loop, and time - step iteration loop for three - layer nested loop setting, the inflow flood and flood regulation calculation process of cascade reservoirs are simulated hour by hour, reservoir by reservoir, and level by level to achieve model construction.

[0039] Furthermore, the S305: Model construction based on three - layer nested loops includes:

[0040] S3051: Identification of series - parallel relationships of cascade reservoirs: Extract the topological structure of cascade reservoirs in the area to be simulated from the database, identify the series, parallel, and combined series - parallel relationships between cascade reservoirs, and determine the calculation level of each reservoir;

[0041] S3052: Simulation of sub - basin flood process: Based on the flood forecasting model, calculate the flood discharge process of each sub - basin, and store the simulated sub - basin flood forecasting results in the sub - basin flood forecasting result library;

[0042] S3053: Model simulation based on three - layer nested loops: Adopt the three - layer loop setting method to form an iterative calculation loop with the calculation level as the first level, all reservoirs at the corresponding level as the second level, and all time steps within the simulation period as the third level.

[0043] Furthermore, the model simulation based on three - layer nested loops includes:

[0044] Taking a certain reservoir at the current calculation level as the object, based on the flood discharge process of the upstream reservoir corresponding to the current reservoir, use the river channel confluence calculation model to calculate the flood process reaching the dam of the current reservoir from the upstream reservoir, and combine the sub - basin flood process simulation results to obtain the flood process of the current reservoir's interval inflow, and determine the inflow flood process of the current reservoir.

[0045] Furthermore, the model construction based on three - layer nested loops also includes:

[0046] S3054: Based on the model simulation results of three - layer nested loops, taking the inflow flood discharge process of the current reservoir as input data, use the flood control operation model to calculate the hourly flood control operation of the current reservoir, and simulate the water level change process and the discharge process of the current reservoir;

[0047] S3055: Use the outflow result of the current reservoir as input data to provide boundary conditions for the river confluence simulation of the reservoir at the next calculation level;

[0048] S3056: After traversing all the reservoirs at the current calculation level, enter the reservoir loop at the next calculation level and repeat the above process until all the reservoirs at all calculation levels are calculated;

[0049] S3057: When the loops of all reservoirs at all calculation levels end, output the water level change process and the flood outflow process of each cascade reservoir in the simulation area and save them to the reservoir flood regulation calculation result library.

[0050] Further, in the fourth step, based on a three-layer nested loop to construct a model simulation and scheme evaluation, the specific steps include:

[0051] S401: Review and storage of basic data: Based on the collected and sorted basin basic data, reservoir basic data, reservoir flood control operation regulations and water regime and rainfall monitoring network information, after manual review, perform standardized processing and storage;

[0052] S402: Modeling preprocessing and storage: Based on the generation and processing of the topological structure considering the series and parallel relationships of cascade reservoirs, extract the river network water system, divide sub-basins and generate the topological structure of cascade reservoirs, and perform standardized processing and storage;

[0053] S403: Model selection and parameter storage: Combine the runoff generation and confluence characteristics of the area to be simulated and the completeness of basic data, select the corresponding flood forecasting model, river confluence calculation model, and reservoir flood regulation calculation model, and determine the model parameters through parameter calibration;

[0054] S404: Database configuration: Configure the link method of database tables to complete the database configuration;

[0055] S405: Scheme setting: For the cascade reservoirs in the area to be simulated, combine historical water regime and rainfall information and the forecast rainfall process to set the flood forecasting scheme; considering the flood control safety of the flood control protection area downstream of the reservoir, combine the current flood situation of the reservoir to set the joint operation scheme;

[0056] S406: Parameter reception and model operation: Determine the operation parameters of the start time of the forecast period, the length of the forecast period, the time step length, and the length of the warm-up period, and input them into the corresponding flood forecasting model, river confluence calculation model, and reservoir flood regulation calculation model to operate the models;

[0057] S407: Flood process simulation under a given scheme: Based on the flood forecasting scheme, simulate the flood process at the outlet section of each sub-basin and perform data analysis and display;

[0058] S408: Simulation of the scheduling process under a given scenario: Simulate the joint scheduling process of cascade reservoirs based on the joint scheduling scheme, and conduct data analysis and display.

[0059] S409: By setting different scenarios, simulate the flood process and the reservoir scheduling process respectively, and conduct comparative analysis and effect evaluation of the scenarios in combination with the simulation results.

[0060] The present invention provides another technical solution, a flood control scheduling simulation system suitable for multi-level series-parallel cascade reservoirs, including:

[0061] The basic data processing module is used to collect and process the basin basic data, reservoir basic data, and water regime and rainfall monitoring network information.

[0062] The topological structure generation module is used to analyze the series-parallel relationship of cascade reservoirs based on the data collected by the basic data processing module, generate the topological structure of cascade reservoirs, and output a standardized topological relationship table.

[0063] The sub-basin flood forecasting module is used to select a flood forecasting model according to the runoff generation and concentration characteristics of the sub-basin and calibrate the model parameters, and simulate and output the flood flow process of the sub-basin.

[0064] The reservoir flood routing module is used to simulate the inflow flood process and flood control scheduling process of the reservoir level by level according to the calculation level order based on the topological structure relationship of cascade reservoirs, calculate the river channel confluence between the upper and lower reservoirs, and output the water level change process and the discharged flood process of each reservoir.

[0065] The scenario setting and simulation evaluation module is used to run the model based on the set flood forecasting scenario and joint scheduling scenario, evaluate the flood control scheduling process and effect of cascade reservoirs under the set scenario, generate an operation evaluation report, and provide optimization suggestions for the scheduling scenario, providing technical support for optimizing the flood control scheduling scenario.

[0066] Compared with the prior art, the beneficial effects of the present invention are:

[0067] The flood control scheduling simulation method and system suitable for multi-level series-parallel cascade reservoirs provided by the present invention fully integrate the basin basic data, reservoir characteristic data, and water regime and rainfall monitoring data, form a topological structure based on the series-parallel relationship of cascade reservoirs, construct a flood forecasting and joint scheduling model for cascade reservoirs, and at the same time, in combination with the set flood forecasting scenario and joint scheduling scenario, conduct process simulation and scenario evaluation. The present invention can be adapted to cascade reservoirs with complex series-parallel relationships such as series, parallel, or mixed connection, can realize the preview of the flood control scheduling process and scenario comparison under different joint scheduling scenarios, and improve the scientificity and effectiveness of flood control scheduling. Description of the Drawings

[0068] Figure 1Flow chart of the flood control operation simulation method for adapting to multi-level series-parallel cascade reservoirs of the present invention;

[0069] Figure 2 Schematic diagram of the river network and sub-watershed of the present invention;

[0070] Figure 3 Schematic diagram of the cascade reservoir topological structure of the present invention;

[0071] Figure 4 Schematic diagram of the flood control operation simulation method for cascade reservoirs based on topological structure of the present invention;

[0072] Figure 5 Schematic diagram of the construction of the real-time forecasting and joint operation model for cascade reservoirs based on three-layer nested loops of the present invention;

[0073] Figure 6 Sub-watershed flood forecasting results in the specific embodiment of the present invention;

[0074] Figure 7 Operation results of Huashan Reservoir under Joint Operation Plan 1 of the present invention;

[0075] Figure 8 Operation results of Feishahe Reservoir under Joint Operation Plan 1 of the present invention;

[0076] Figure 9 Operation results of Huashan Reservoir under Joint Operation Plan 2 of the present invention;

[0077] Figure 10 Operation results of Feishahe Huashan Reservoir under Joint Operation Plan 2 of the present invention;

[0078] Figure 11 Comparison of the operation results of Huashan Reservoir under two groups of joint operation plans of the present invention;

[0079] Figure 12 Comparison of the operation results of Feishahe Reservoir under two groups of joint operation plans of the present invention. Detailed implementation manners

[0080] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0081] To solve the technical problems in the prior art, where the scheduling mainly targets a single reservoir, it is difficult to consider the interaction between cascade reservoirs and the benefits of joint scheduling, and it is difficult to cope with complex series-parallel cascade reservoir systems, and it is impossible to effectively simulate the flood routing and joint scheduling process of multi-level series-parallel cascade reservoirs, please refer to Figures 1 - 12 , the present embodiment provides the following technical solutions:

[0082] A flood control scheduling simulation method suitable for multi-level series-parallel cascade reservoirs, including the following steps:

[0083] Step 1, collection and collation of basic data: Collect the basin basic data, reservoir basic data, reservoir flood control scheduling regulations and water regime and rainfall monitoring network information of the area to be simulated;

[0084] In this embodiment, the basin basic data includes: the basin water system map containing rivers, lakes, and reservoirs, high-precision elevation data (DEM), and the basic data of rivers, lakes, and reservoirs; the reservoir basic data includes: the characteristic water levels, characteristic storage capacities, water level-storage capacity curves, and water level-discharge curves of the cascade reservoirs; the water regime and rainfall monitoring network information includes: the water regime and rainfall monitoring network information and its measured data including rain gauges, water level gauges, flow gauges, and hydrological stations;

[0085] Step 2, generation and processing of the topological structure considering the series-parallel relationship of cascade reservoirs: Extract the river network water system based on the collected data, divide the sub-basins, analyze the series-parallel relationship of the cascade reservoirs, generate the topological structure of the cascade reservoirs, and perform standardization processing to convert the generated topological structure into a unified and standard form for subsequent analysis, calculation, and model application;

[0086] Step 3, construction of the flood control scheduling simulation method and model based on the topological structure: Combine the generated topological structure relationship of the cascade reservoirs, perform sub-basin process calculation, flood control scheduling calculation, and river channel confluence calculation respectively, and construct a model based on three-layer nested loops to simulate the inflow flood and flood regulation calculation process of the cascade reservoirs step by step from upstream to downstream;

[0087] Step 4, construction of the model simulation and plan evaluation based on three-layer nested loops: Set flood forecasting plans and joint scheduling plans, simulate the flood control scheduling process of the cascade reservoirs under different plans, and conduct plan comparison analysis and effect evaluation in combination with the simulation results. Its steps include:

[0088] S401: Review and storage of basic data. Based on the basin basic data, reservoir basic data, reservoir flood control scheduling regulations, and water regime and rainfall monitoring network information collected and collated in Step 1, after manual review, perform standardization processing and storage according to the requirements of "Table Structure and Identifiers for Real-Time Rainfall and Water Regime Database" (SL323-2011);

[0089] S402: Modeling preprocessing and database storage. Based on the generation and processing of the topological structure considering the series - parallel relationship of cascade reservoirs, river network water system extraction, sub - watershed division, and the generation of the topological structure of cascade reservoirs are carried out, and then standardized processing is performed and stored in the database.

[0090] S403: Model selection and parameter database storage. Considering the runoff generation and concentration characteristics of the area to be simulated and the completeness of basic data, appropriate flood forecasting models, river channel routing models, and reservoir flood regulation calculation models are selected. The model parameters are determined through parameter calibration, and then standardized processing is carried out according to the requirements of "Table Structure and Identifiers for Real - Time Rainfall and Water Level Database" (SL323 - 2011) and stored in the database.

[0091] S404: Database configuration. Configure the connection methods of database tables such as basic data, modeling data, and model parameters to complete the database configuration.

[0092] S405: Scheme setting. For the cascade reservoirs in the area to be simulated, combined with historical rainfall and water level information and the predicted rainfall process, set the flood forecasting scheme. Considering the flood control safety of the flood - control protected area downstream of the reservoir and the current flood situation of the reservoir, set the joint operation scheme.

[0093] S406: System parameter reception and model operation. Determine the operation parameters such as the start time of the forecasting period, the length of the forecasting period, the time step length, and the length of the warm - up period, and input them into the corresponding flood forecasting models, river channel routing models, and reservoir flood regulation calculation models to run the models.

[0094] S407: Flood process simulation under a given scheme: Based on the given flood forecasting scheme, simulate the flood processes at the outlet cross - sections of each sub - watershed, and conduct data analysis and display.

[0095] S408: Operation process simulation under a given scheme: Based on the given joint operation scheme, simulate the joint operation process of cascade reservoirs, and conduct data analysis and display.

[0096] S409: By setting different schemes, respectively conduct flood process and reservoir operation process simulations, and conduct scheme comparison analysis and effect evaluation in combination with the simulation results.

[0097] In this embodiment, through the comprehensive integration of basin - wide basic data, reservoir characteristic data, and rainfall and water level monitoring data, based on the cascade reservoir system with standardized topological structure, simulations are carried out in combination with flood forecasting schemes and joint operation schemes. At the same time, comprehensive evaluation is carried out based on the simulation results, which improves the scientificity and effectiveness of flood control operation. It can effectively solve the problems in the existing technology that mainly focus on the operation of single reservoirs and are difficult to consider the interaction between cascade reservoirs and the benefits of joint operation. At the same time, it can handle complex series - parallel cascade reservoir systems and simulate the flood evolution and joint operation processes of multi - level series - parallel cascade reservoirs.

[0098] In this embodiment, step two, the generation and processing of the topological structure considering the series - parallel relationship of cascade reservoirs specifically include:

[0099] S201: River network water system extraction: Based on the high - precision elevation data and the river network map of the basin to be simulated, hydrological analysis is carried out to divide the basic basin (for example, the area of the basic basin is 5 km 2 ), and extract the river network consistent with the real water system;

[0100] S202: Sub - basin division: According to the actual distribution position of the cascade reservoirs in the river network, merge the boundaries of the basic basins, and divide the basic basins into sub - basins consistent with the reservoir catchments, making it adapt to the catchments and river network of the cascade reservoirs. At the same time, form a complete outlet section of the sub - basin. In each sub - basin, combined with the river network flow direction, clarify the main stream and tributary paths, and divide several sub - basins;

[0101] S203: Analysis of the series - parallel relationship of cascade reservoirs: Based on the river network and sub - basin scope, clarify the catchment area (i.e., the corresponding sub - basin) of each reservoir. According to the confluence relationship between upstream and downstream reservoirs, identify the series - parallel relationship of cascade reservoirs, including: Parallel relationship: If the incoming flood of a reservoir is not affected by other reservoirs, it forms a parallel relationship with other reservoirs; Series relationship: If the discharged flood of a certain reservoir flows into a downstream reservoir, the two form a series relationship; Mixed - series relationship: Combine the parallel and series relationships to analyze the complex mixed - series cascade reservoir structure;

[0102] In this embodiment, for the parallel relationship: Reservoir 1 and Reservoir 2 are independent of each other and both directly receive the flood in their respective sub - basins. For the series relationship: The discharged floods of Reservoir 1 and Reservoir 2 are confluent through the river channel and first flow into Reservoir 3, and the discharged flood of Reservoir 3 is confluent through the river channel and flows into Reservoir 4. For the mixed - series relationship: The parallel Reservoir 1 and Reservoir 2 jointly affect the series Reservoir 3 and Reservoir 4;

[0103] S204: Topological structure generation: Based on the series - parallel relationship of the cascade reservoirs, establish the association relationship with upstream and downstream reservoirs for each reservoir to form a preliminary topological structure, and assign calculation levels in the order from upstream to downstream, including but not limited to calculation level 1, calculation level 2, and calculation level 3;

[0104] In this embodiment, an independent reservoir without an upstream reservoir, that is, an independent reservoir directly receiving the runoff from the sub - basin, is set as calculation level 1 (such as Reservoir 1 and Reservoir 2), a reservoir receiving the discharged flood of a calculation - level - 1 reservoir is set as calculation level 2 (such as Reservoir 3), and a reservoir receiving the discharged flood of a calculation - level - 2 reservoir is set as calculation level 3 (such as Reservoir 4);

[0105] S205: Standardization Processing: Perform data formatting on the preliminarily formed cascade reservoir topological structure, construct a topological relation table, record information including reservoir number, calculation level, upstream reservoir number, and the source of the inflow (sub-basin / upstream reservoir), and store the standardized topological structure data in the database to form a standardized topological structure table for subsequent model calls.

[0106] In this embodiment, by truly reflecting the river network structure and the catchment area of the cascade reservoir, the accuracy of the geographical information for flood simulation is ensured, which is beneficial to more accurately predicting the flood process, clarifying the series and parallel relationships of the cascade reservoir, helping to formulate a more reasonable reservoir operation plan, improving benefits such as flood control and power generation, and realizing the reasonable allocation of computing resources.

[0107] In this embodiment, Step 3: The flood control operation simulation method and model construction for cascade reservoirs based on the topological structure specifically include:

[0108] S301: Sub-basin flood process calculation method:

[0109] Based on the sub-basin division results, combined with the flood forecasting scheme, use the flood forecasting model to simulate the flood flow process of each sub-basin. The calculation formula is as follows:

[0110]

[0111] In the formula, represents the simulated flow of the m-th sub-basin, MODEL flood represents the flood forecasting model, represents the geographical characteristics of the m-th sub-basin, represents the meteorological data within the m-th sub-basin, and β flood represents the flood forecasting model parameters;

[0112] If a certain sub-basin completely covers the reservoir catchment area, the flow process at the outlet section of this sub-basin is the inflow flood process of this reservoir; if a certain sub-basin only covers a part of the reservoir catchment area, the flow process at the outlet section of this sub-basin is the flood process of the corresponding catchment interval of this reservoir.

[0113] S302: Flood control operation calculation method for independent reservoirs:

[0114] Based on the calculation level allocation results, extract the independent reservoirs with a calculation level of 1 in the topological structure of the cascade reservoir. For a certain independent reservoir, calculate the total inflow of the current independent reservoir, and combined with the set flood control operation plan, use the reservoir flood regulation calculation model to simulate the flood control operation process of the independent reservoir to obtain the water level change process and the downstream flood process. The calculation formula is as follows:

[0115]

[0116] In the formula, j1 represents the jth reservoir at calculation level 1, represents the total inflow of the j1th reservoir, represents the number of sub - basins corresponding to the j1th reservoir, represents the simulated flow of the sub - basin where the jth reservoir receives inflow, represents the outflow of the j1th reservoir, MODEL operation represents the reservoir flood regulation calculation model, represents the initial water level of the j1th reservoir, represents the water level - storage capacity curve of the j1th reservoir, represents the water level - discharge curve of the j1th reservoir, represents the flood control operation plan of the j1th reservoir;

[0117] S303: River confluence calculation method between upper and lower reservoirs:

[0118] Extract all reservoirs with a calculation level greater than 1 from the topological structure of cascade reservoirs based on the calculation level allocation results. For a certain reservoir at the current calculation level, obtain the flood discharge process of the upstream reservoir corresponding to the current reservoir. Use the river confluence calculation model to simulate the river confluence process from the downstream of each upstream reservoir dam to the upstream of the current reservoir dam, and calculate the total inflow of the current reservoir. The calculation formula is as follows:

[0119]

[0120] In the formula, j k represents the jth reservoir at calculation level k, represents the j k number of upstream reservoirs of the th reservoir, represents the total flood discharge of the upstream reservoirs reaching the j k th reservoir, represents the flow reaching the j k th reservoir after the lth upstream reservoir discharges flood, MODEL routing represents the river confluence calculation model, represents the flood discharge of the lth upstream reservoir, and respectively represent the river length and slope from the downstream of the lth upstream reservoir dam to the upstream of the j k th reservoir dam, β routing represents the parameter of the river confluence calculation model;

[0121] S304: Flood control operation calculation method for cascade reservoirs:

[0122] For a certain reservoir with a calculation level greater than 1, combined with the set scheduling plan and the calculated total inflow, the flood regulation calculation model of the reservoir is used to simulate the flood control scheduling process of the current reservoir, and the water level change process and the released flood process of the current reservoir are obtained. The calculation formula is as follows:

[0123]

[0124] In the formula, j k represents the jth reservoir at the calculation level k, represents the j k total inflow of the jth reservoir, represents the j k simulated flow in the catchment area of the jth reservoir, represents the j k outflow of the jth reservoir, represents the j k initial water level [m] of the jth reservoir, represents the j k water level - storage curve of the jth reservoir, represents the j k water level - discharge curve of the jth reservoir, represents the flood control scheduling plan of the jth reservoir;

[0125] S305: Model construction based on three - layer nested loops:

[0126] Through the calculation level loop, reservoir traversal loop, and time step iteration loop for three - layer nested loop setting, the flood inflow and flood regulation calculation process of cascade reservoirs are simulated step - by - step, reservoir - by - reservoir, and level - by - level to achieve model construction.

[0127] In this embodiment, the method of three - layer loop setting is as follows:

[0128] From the minimum calculation level to the maximum calculation level, a calculation level loop of cascade reservoirs is formed, and flood regulation calculations of reservoirs are carried out level - by - level; at each calculation level, all reservoirs at this level are traversed, and flood regulation calculations are carried out for each reservoir; for each reservoir at the current calculation level, starting from the simulation start time, the time step is determined in combination with the forecast period length and the time step length to form a time step iteration loop within the simulation period, and flood regulation calculations are carried out step - by - step, so as to generate a real - time forecast and joint scheduling model of cascade reservoirs.

[0129] In this embodiment, by calculating the flood process of sub-watersheds step by step, the reservoir inflow flood is more accurately simulated, providing reliable basic data for flood control scheduling. The flood control scheduling calculations for independent reservoirs and cascade reservoirs contribute to formulating scientific reservoir scheduling plans, effectively reducing flood disasters, clarifying the logical sequence of joint scheduling calculations, ensuring the orderly progress of the flood routing calculation of cascade reservoirs, improving the calculation efficiency and the accuracy of simulation results, being able to handle complex cascade reservoir structures, and meeting the reservoir scheduling requirements of different series-parallel relationships.

[0130] In this embodiment, S305: Model construction based on three-layer nested loops includes:

[0131] S3051: Identification of the series-parallel relationship of cascade reservoirs: Extract the topological structure of cascade reservoirs in the area to be simulated from the database, identify the series, parallel, and mixed connection relationships between cascade reservoirs, and determine the calculation level of each reservoir;

[0132] S3052: Simulation of the sub-watershed calculation process: Calculate the flood flow process of each sub-watershed based on the flood forecasting model, and store the simulated sub-watershed flood forecasting results in the sub-watershed flood forecasting result library;

[0133] S3053: Model construction based on three-layer nested loops: Adopt a three-layer loop setting method to form an iterative calculation loop with the calculation level as the first layer, all reservoirs at the corresponding level as the second layer, and all time periods within the simulation period as the third layer. Taking a certain reservoir at the current calculation level as the object, based on the downstream flood process of the upstream reservoir corresponding to the current reservoir, use the river channel confluence routing model to calculate the flood process reaching the dam of the current reservoir from the downstream of the upstream reservoir, and combine the simulation results of the sub-watershed flood process to obtain the flood process of the confluence of the current reservoir's interval, and determine the inflow flood process of the current reservoir:

[0134] S3054: Based on the simulation results of the model based on three-layer nested loops, take the inflow flood flow process of the current reservoir as input data, and use the flood control scheduling model to perform the hourly flood control scheduling calculation of the current reservoir, and simulate the change process of the reservoir water level and the downstream discharge process of the current reservoir;

[0135] S3055: Take the downstream discharge result of the current reservoir as input data to provide boundary conditions for the river channel confluence simulation of the next calculation level reservoir;

[0136] S3056: When all reservoirs at the current calculation level are traversed, enter the reservoir loop of the next calculation level, and repeat the above process until all reservoirs at all calculation levels are calculated;

[0137] S3057: When the reservoir cycle of all calculation levels ends, output the water level change process and the flood discharge process of each cascade reservoir in the simulation area, and save them to the reservoir flood regulation calculation result library.

[0138] In this embodiment, by considering the series and parallel relationships of cascade reservoirs, the simulation of the flood control operation process of complex cascade reservoirs is realized. By identifying the series and parallel relationships of cascade reservoirs and performing flood regulation calculations step by step, the flood process and water level changes of each reservoir can be simulated more accurately, improving the accuracy of the simulation results. It can adapt to different types of cascade reservoirs, including series, parallel, and mixed-connected reservoirs, with strong adaptability. Through a three-layer nested loop, the automatic operation of the model is realized, improving the simulation efficiency and simulating the flood control operation process of cascade reservoirs under different scenarios.

[0139] A specific embodiment of the present invention is a cascade reservoir object formed by two reservoirs, Huashan Reservoir and Feisha River Reservoir, on the Shihe River, a tributary of the Huaihe River. In this embodiment, the simulation operation starts at 8:00 on July 14, 2024, the forecast period is selected as 96 hours (i.e., 4 days), the calculation time step is 1 hour, and the flood forecasting and joint operation process of the Huashan-Feisha River cascade reservoir is simulated.

[0140] Step 1, Collection and collation of basic information:

[0141] The Shihe River is a right-bank tributary of the upper reaches of the Huaihe River, with a drainage area of 2012 km 2 , and the main stream length is 147 km. Among them, in this implementation case, the drainage area involved is 174 km 2 .

[0142] (1) Basin basic data:

[0143] The Huashan Reservoir intercepts the upper reaches of the Shihe River in the Huaihe River Basin. It is a large-scale water conservancy project mainly for irrigation, with comprehensive benefits such as flood control, power generation, and aquaculture. The rainfall-receiving area of the Huashan Reservoir is 129 km 2 , the river length above the dam site is 24.8 km, and the average river slope is 7.68‰.

[0144] The Feisha River Reservoir is a medium-sized reservoir mainly for flood control, irrigation, and water supply, with comprehensive benefits such as power generation and aquaculture. The Feisha River Reservoir is located downstream of the Huashan Reservoir, with a total rainfall-receiving area of 174 km 2 . After deducting the intercepted area of the Huashan Reservoir, the rainfall-receiving area of the interval is 45 km 2 , the interval river length is 12.5 km, and the average river slope is 3.3‰.

[0145] (2) Reservoir basic data:

[0146] The normal storage level of Huashan Reservoir is 237.00 m, the design flood level is 240.35 m, the check flood level is 242.14 m, and the flood control limited level during the flood season is the normal storage level of 237.00 m. The inlet elevation of the irrigation pipeline of Huashan Reservoir is 200 m, and the designed flow rate of the pipeline is 30 m 3 / s.

[0147] The normal storage level of Feishahe Reservoir is 182.25 m, the design flood level is 183.87 m, the check flood level is 185.20 m, and the flood control limited level during the flood season is the normal storage level of 182.25 m. The inlet elevation of the water conveyance tunnel of Feishahe Reservoir is 161 m, and the designed flow rate of the pipeline is 80.5 m 3 / s.

[0148] (3) Reservoir flood control operation regulations:

[0149] The real-time operation regulations of Huashan Reservoir and Feishahe Reservoir are as follows:

[0150] 1) Huashan Reservoir:

[0151] ① When the reservoir water level approaches the normal storage level, the reservoir water level can be adjusted by generating electricity through the water conveyance tunnel or supplying water for irrigation and replenishing water to the downstream Feishahe Reservoir.

[0152] ② When the reservoir water level exceeds the normal storage level, free flood discharge is carried out through the open spillway.

[0153] 2) Feishahe Reservoir:

[0154] ① Flood season water level: The normal storage level of the reservoir, and when the normal water level is reached, the reservoir will overflow by itself.

[0155] ② Flood control operation: When there is a conflict between the reservoir flood discharge and the downstream river channel, the safety of the downstream river channel shall be subordinated to the safety of the reservoir.

[0156] (4) Information of the water regime and rainfall monitoring station network:

[0157] Since in this implementation case, a hypothetical rainfall process is adopted, therefore, it is not necessary to collect the information of rain gauges within the basin area, and only the measured data of the water level stations of Huashan Reservoir and Feishahe Reservoir need to be collected.

[0158] Step 2, generation of the topological structure considering the series-parallel relationship of cascade reservoirs:

[0159] According to the method described in Step 2, combined with the series-parallel topological structure of the Huashan-Feishahe cascade reservoir generated in this embodiment, the specific steps are as follows:

[0160] (1) Extract the river network water system according to the method described in Step 2 to obtain the water system distribution map of the basins where Huashan Reservoir and Feishahe Reservoir are located in this embodiment;

[0161] (2) Sub - basin division is carried out according to the method described in step two to obtain the sub - basin division results and the runoff generation and concentration paths in this implementation case;

[0162] (3) Analysis of the series - parallel relationship of cascade reservoirs. Huashan Reservoir and Feishahe Reservoir form a series of cascade reservoirs. After the flood generated by heavy rain in the upstream catchment area of Huashan Reservoir enters the reservoir, it is regulated by Huashan Reservoir and then discharged. The flood discharge process of Huashan Reservoir is superimposed on the flood process in the catchment area between Huashan - Feishahe Reservoirs and then flows into Feishahe Reservoir. After being regulated by Feishahe Reservoir, it is discharged;

[0163] (4) Topological structure generation. According to the series - parallel relationship of cascade reservoirs analyzed in step (3), a computational topological structure of the cascade reservoirs formed by the series connection of Huashan Reservoir - Feishahe Reservoir is generated, thereby determining that the calculation level of Huashan Reservoir is 1 and that of Feishahe Reservoir is 2;

[0164] Step 3, the flood control operation simulation method for cascade reservoirs based on topological structure:

[0165] Combined with the sub - basin results divided in step 2 and the generated topological structure, according to the method described in step three, determine the flood control operation simulation method for Huashan - Feishahe cascade reservoirs. The specific method is as follows:

[0166] (1) Calculation of flood processes for 6 sub - basins:

[0167] For the 6 divided sub - basins, a flood forecasting model is used to simulate the flood processes at the outlet sections of 6 sub - basins, namely the main stream basin of Shihe River upstream of Huashan Reservoir, the catchment area of tributary 1 flowing into Huashan Reservoir, the catchment area of tributary 2 flowing into Huashan Reservoir, the catchment area of tributary 2 flowing into Huashan Reservoir, the catchment area of the reservoir area of Huashan Reservoir, and the catchment area between Huashan - Feishahe Reservoirs;

[0168] (2) Flood control operation calculation for independent reservoirs:

[0169] For the independent reservoir with a calculation level of 1 (i.e., Huashan Reservoir), based on the simulation results of sub - basin flood forecasting, the flood processes of 5 sub - basins, namely the main stream basin of Shihe River upstream of Huashan Reservoir, the catchment area of tributary 1 flowing into Huashan Reservoir, the catchment area of tributary 2 flowing into Huashan Reservoir, the catchment area of tributary 2 flowing into Huashan Reservoir, and the catchment area of the reservoir area of Huashan Reservoir, are superimposed to calculate the total inflow of Huashan Reservoir; combined with the set operation plan of Huashan Reservoir, a reservoir flood regulation calculation model is used to simulate the flood control operation process of Huashan Reservoir to obtain the water level change process and the flood discharge process of Huashan Reservoir;

[0170] (3) River channel confluence calculation between upper and lower reservoirs:

[0171] For the reservoir with calculation level 2 (i.e., Feisha River Reservoir), based on the simulation results of the flood control operation calculation model of its upper reservoir (i.e., Huashan Reservoir), obtain the flood discharge process of Huashan Reservoir; adopt the river channel confluence calculation model to simulate the river channel confluence process from downstream of Huashan Reservoir Dam to in front of Feisha River Reservoir Dam, and obtain the flow rate of Huashan Reservoir flowing into Feisha River Reservoir.

[0172] (4) Flood control operation calculation of cascade reservoirs:

[0173] For the reservoir with calculation level 2 (i.e., Feisha River Reservoir), based on the simulation results of the flood forecasting model, obtain the flood process in the catchment area between Huashan - Feisha River reservoirs, superimpose the flood volume of Huashan Reservoir flowing into Feisha River Reservoir, and calculate the total inflow of Feisha River Reservoir; combined with the set operation plan of Feisha River Reservoir, adopt the reservoir flood regulation calculation model to simulate the flood control operation process of Feisha River Reservoir, and obtain the water level change process and flood discharge process of Feisha River Reservoir.

[0174] (5) Logical sequence of joint operation calculation:

[0175] According to the sequence of calculation levels 1 and 2, perform flood regulation calculations for all reservoirs at the corresponding calculation levels step by step, so as to realize the simulation of the flood regulation calculation process of each reservoir in the cascade reservoirs, and obtain the water level change process and flood discharge process of all reservoirs.

[0176] Furthermore, construction of the real - time forecasting and joint operation model for cascade reservoirs based on the set plan:

[0177] Construct the flood forecasting and operation model for Huashan - Feisha River cascade reservoirs according to the method described in step 3, specifically as follows:

[0178] (1) Review and storage of basic data:

[0179] Based on the basic information collected and sorted in step 1, review and store the basic data of the reservoir and the reservoir flood control operation regulations.

[0180] (2) Pre - processing and storage for modeling:

[0181] Extract the river network water system, divide sub - basins, and generate the topological structure of cascade reservoirs according to the method described in step S2, and store them after standardization.

[0182] (3) Model selection and parameter storage:

[0183] Select the Xin'anjiang model to forecast the flood process of 6 sub-basins, and select the peak staggering and superposition method to calculate the river confluence from downstream of Huashan Reservoir to the front of Feishahe Reservoir. When using the peak staggering and superposition method, the length and slope of the confluence river channel need to be provided. According to the basic information collected in Step 1, the river length from downstream of Huashan Reservoir to the front of Feishahe Reservoir is 12.5 km, and the average river slope is 3.3‰. Specifically Figure 11 in fields RIVER_LENGTH and RIVER_SLOPE;

[0184] (4) Scheme setting:

[0185] For the Huashan-Feishahe cascade reservoir, combining historical and forecast water and rain information, considering the flood control safety of the flood control protection area downstream of the reservoir, set the flood forecast scheme and the joint operation scheme;

[0186] (5) Database configuration:

[0187] Provide the database table names and their database connection methods for the basic information, model parameters, scheme settings, calculation results, etc. of the Huashan-Feishahe cascade reservoir modeling to complete the database configuration;

[0188] (6) Construction of real-time forecast and joint operation model:

[0189] Adopt the methods described in Step S3 and Step S4 to complete the construction of the real-time forecast and joint operation model of the Huashan-Feishahe cascade reservoir.

[0190] Step 4, simulation and analysis of the flood control operation process of the cascade reservoir based on the set scheme:

[0191] Carry out the simulation and analysis of the flood control operation process of the Huashan-Feishahe cascade reservoir according to the method described in Step S4. The specific steps are as follows:

[0192] (1) Scheme setting:

[0193] 1) Flood forecast scheme:

[0194] Set 1 group of flood forecast schemes (ground rainfall + given rainfall mode), and the preheating period length of the Xin'anjiang model is taken as 90 days. Under this flood forecast scheme, it is assumed that the hourly areal rainfall of the whole basin in the first 48 hours before the forecast period is 10 mm and there is no rainfall in the next 48 hours, and ground rainfall is adopted during the preheating period of the Xin'anjiang model.

[0195] 2) Cascade reservoir joint operation scheme:

[0196] Set 2 groups of joint operation schemes for the Huashan-Feishahe cascade reservoir. The specific situations are as follows:

[0197] ① Joint operation scheme 1 (rule-based operation): Both Huashan Reservoir and Feishahe Reservoir adopt the operation regulations. The specific operation scheme is shown inFigure 9 ;

[0198] ② Combined dispatching plan 2 (instruction dispatching): For Huashan Reservoir and Feisha River Reservoir, instruction dispatching is adopted. After the user analyzes the water regime and rainfall of the basin, the dispatching plans for the two reservoirs are set. For the specific dispatching plan, see Figure 12 .

[0199] (2) System parameter reception and operation model:

[0200] ① Receive the system operation parameters, determine that the calculation start time is 8:00 on July 14, 2024, the calculation time step is 1 hour, and the forecast period length is 96 time periods, and run the model in the following order:

[0201] ② Based on the set flood forecasting plan, run the flood forecasting model to simulate the flood processes of 6 sub-basins;

[0202] ① Based on the set combined dispatching plan 1 and combined with the simulation results of the flood forecasting plan, simulate the combined dispatching process of Huashan - Feisha River Reservoirs;

[0203] ③ Based on the set combined dispatching plan 2 and combined with the simulation results of the flood forecasting plan, simulate the combined dispatching process of Huashan - Feisha River Reservoirs.

[0204] (3) Sub-basin flood forecasting results:

[0205] Based on the rainfall process provided by the flood forecasting plan (ground rainfall + given rainfall mode), run the flood forecasting model to obtain the forecast flood processes of 6 sub-basins, see Figure 6 .

[0206] (4) Simulation results under the set combined dispatching plan 1:

[0207] Under the set combined dispatching plan 1, Huashan Reservoir and Feisha River Reservoir are dispatched according to the set combined dispatching plan.

[0208] 1) Huashan Reservoir:

[0209] From Figure 7 it can be seen that because it is assumed in the flood forecasting plan that the hourly areal rainfall of the whole basin is 10 mm in the first 48 hours, the inflow flood volume of Huashan Reservoir in the early stage of the forecast is relatively large, and the maximum flood peak flow reaches 365 m 3 / s; the water level of Huashan Reservoir at the initial moment is 230.94 m (lower than the normal storage level of 237.0 m); the combined dispatching plan 1 sets the dispatching plan for Huashan Reservoir as: when the water level exceeds the normal storage level of 237.00 m, it is freely discharged through the open spillway);

[0210] From Figure 7It can be seen that with the inflow of floodwater, the reservoir water level of Huashan Reservoir gradually increases. At the 36th time period when the calculation starts, the reservoir water level exceeds the normal storage level of 237.0 m, and the spillway discharges freely. However, the inflow discharge is greater than the outflow discharge, and the reservoir water level keeps rising. Until the 55th time period when the calculation starts, the inflow discharge is less than the outflow discharge, and the reservoir water level gradually decreases. During the whole simulation process, the maximum reservoir water level is 238.86 m, which is higher than the normal storage level of 237.0 m and lower than the design flood level of 240.35 m.

[0211] 2) Feishahe Reservoir:

[0212] It can be seen from Figure 8 that due to the impounding effect of Huashan Reservoir, the inflow flood volume of Feishahe Reservoir is smaller than that of Huashan Reservoir, and the maximum flood peak discharge is 177 m 3 / s; the water level of Feishahe Reservoir at the initial moment is 175.57 m (lower than the normal storage level of 182.25 m); the operation plan of Feishahe Reservoir set in the joint operation plan 1 is: reach the normal storage level of 182.25 m and discharge freely through the spillway;

[0213] It can be seen from Figure 8 that with the inflow of the floodwater released from Huashan Reservoir and the floodwater from the intermediate area, the reservoir water level of Feishahe Reservoir gradually increases. At the 52nd time period when the calculation starts, the reservoir water level exceeds the normal storage level of 182.25 m, and the spillway starts to discharge freely. However, the inflow discharge is greater than the outflow discharge, and the reservoir water level still keeps rising. Until the 67th time period when the calculation starts, the inflow discharge is less than the outflow discharge, and the reservoir water level gradually decreases. During the whole simulation process, the maximum reservoir water level is 183.09 m, which is higher than the normal storage level of 182.25 m and lower than the design flood level of 183.87 m.

[0214] (5) Set the simulation results under the joint operation plan 2:

[0215] Under the set joint operation plan 2, Huashan Reservoir and Feishahe Reservoir are operated according to the set joint operation plan.

[0216] 1) Huashan Reservoir:

[0217] It can be seen from Figure 9 that since it is assumed in the flood forecasting plan that the hourly areal rainfall over the whole basin is 10 mm in the first 48 hours, the inflow flood volume of Huashan Reservoir is relatively large in the early stage of the forecast, and the maximum flood peak discharge reaches 365 m 3 / s; the water level of Huashan Reservoir at the initial moment is 230.94 m (lower than the normal storage level of 237.0 m); the operation plan of Huashan Reservoir set in the joint operation plan 2 is: pre-discharge using the irrigation water conveyance pipe, and the designed discharge of the irrigation water conveyance pipe is 30 m 3 / s; when the water level exceeds the normal storage level, the spillway discharges freely;

[0218] As can be seen Figure 9 from Figure 9 , while the flood is flowing in, Huashan Reservoir pre-discharges water through the irrigation water conveyance pipeline at a rate of 30 m 3 / s. The inflow is greater than the outflow, and the reservoir water level continues to rise. By the 38th time step at the start of the calculation, the reservoir water level exceeds the normal storage level of 237.0 m, and the spillway discharges freely. However, the inflow is still greater than the total outflow, and the reservoir water level continues to rise until the 56th time step at the start of the calculation, when the inflow is less than the total outflow and the reservoir water level gradually decreases. During the entire simulation process, the maximum reservoir water level is 238.43 m, which is higher than the normal storage level of 237.0 m and lower than the design flood level of 240.35 m.

[0219] 2) Feishahe Reservoir:

[0220] As can be seen Figure 10 from Figure 10 , due to the interception of Huashan Reservoir, the inflow flood volume of Feishahe Reservoir is smaller than that of Huashan Reservoir, and the maximum flood peak flow is 188 m 3 / s; the water level of Feishahe Reservoir at the initial moment is 175.50 m (lower than the normal storage level of 182.25 m); the joint operation plan 2 sets the operation plan of Feishahe Reservoir as follows: pre-discharge water using the water conveyance tunnel, and the designed flow rate of the water conveyance tunnel is 80.5 m 3 / s; when the water level exceeds the normal storage level, the spillway discharges freely;

[0221] As can be seen Figure 10 from Figure 10 , while the flood discharged from Huashan Reservoir and the flood from the intermediate area are flowing in, pre-discharge water through the water conveyance tunnel at a rate of 80.5 m 3 / s. In the first 5 time steps of the calculation, the outflow is greater than the inflow, and the reservoir water level drops slightly; from the 6th time step to the 76th time step of the calculation, since the reservoir water level does not reach the normal storage level, only discharge water through the water conveyance tunnel at a rate of 80.5 m 3 / s, but the inflow is still greater than the outflow, and the reservoir water level gradually rises; starting from the 77th time step, the inflow is less than the outflow, and the reservoir water level gradually decreases. During the entire simulation process, the maximum reservoir water level is 180.13 m, which is lower than the normal storage level of 182.25 m.

[0222] (6) Comparative analysis of the operation processes under the two groups of operation plans:

[0223] As Figure 11 shown in Figure 11 is the comparison of the flood control operation results of Huashan Reservoir under the two groups of joint operation plans. As can be seen from the figure, under joint operation plan 2, Huashan Reservoir has a smaller pre-discharge flow rate and a larger reservoir capacity, resulting in little difference in the change process of the reservoir water level of Huashan Reservoir between joint operation plan 2 and plan 1.

[0224] As Figure 12The figure shows the comparison of the flood control operation results of Feishahe Reservoir under two sets of joint operation schemes. It can be seen from the figure that under Joint Operation Scheme 2, Feishahe Reservoir pre-discharges at 80.5 m 3 / s, making the water level rise of Feishahe Reservoir significantly slower than that in Scheme 1. Under Joint Operation Scheme 1, the highest water level of Feishahe Reservoir reaches 183.09 m, which is higher than the normal storage level of 182.25 m and slightly lower than the design flood level of 183.87 m; while under Joint Operation Scheme 2, the highest water level of Feishahe Reservoir is 180.13 m, significantly lower than the normal storage level of 182.25 m. That is to say, the pre-discharge scheme set in Joint Operation Scheme 2 helps to ensure the flood control safety of Feishahe Reservoir.

[0225] In order to better implement a flood control operation simulation method suitable for multi-level series-parallel cascade reservoirs, the present invention provides a flood control operation simulation system for multi-level series-parallel cascade reservoirs, including:

[0226] A basic data processing module, which is used to collect and process basin basic data, reservoir basic data, and water regime and rainfall monitoring network information, and provide input data for subsequent model calculations;

[0227] A topology structure generation module, which is used to analyze the series-parallel relationship of cascade reservoirs based on the data collected by the basic data processing module, generate the topology structure of the cascade reservoirs, and output a standardized topology relation table, such as Table 1;

[0228] A sub-basin flood forecasting module, which is used to select a suitable flood forecasting model according to the runoff generation and concentration characteristics of the sub-basin, calibrate the model parameters, and simulate and output the flood flow process at the outlet section of the sub-basin;

[0229] A reservoir flood routing calculation module, which is used to simulate the inflow flood process and flood control operation process of the reservoir level by level according to the calculation level sequence based on the cascade reservoir topology structure relationship, calculate the river channel confluence between the upper and lower reservoirs, and output the water level change process and the discharged flood process of each reservoir;

[0230] A scheme setting and simulation evaluation module, which is used to run the model based on the set flood forecasting scheme and joint operation scheme, evaluate the flood control operation process and effect of the cascade reservoirs under the set scheme, generate an operation evaluation report, and provide optimization suggestions for the operation scheme;

[0231] Table 1 Temporal and spatial topology structure relation table of the calculated sub-basins and river network water systems

[0232]

[0233]

[0234] Descriptions of each field in the table structure are as follows:

[0235] 1) Watershed coding: Sub-watershed coding, which is unique.

[0236] 2) Watershed name: The watershed name corresponding to the watershed coding.

[0237] 3) Regulation reservoir coding: When the flood of the sub-watershed flows into the reservoir, a corresponding reservoir coding is given, which is unique.

[0238] 4) Regulation reservoir name: The reservoir name corresponding to the regulation reservoir coding.

[0239] 5) Upstream river channel coding: The upstream river channel / reservoir coding corresponding to the sub-watershed or the regulation reservoir.

[0240] 6) Upstream river channel name: The river channel / reservoir name corresponding to the upstream river channel coding.

[0241] 7) Upstream river channel level: The calculated level of the upstream river channel coding.

[0242] 8) Section stake number: The section stake number where the sub-watershed or the regulation reservoir flows into the upstream river / reservoir.

[0243] 9) Flood peak staggering and superposition: Whether to adopt the flood peak staggering and superposition calculation scheme. The field value of 1 indicates adoption, and the field value of 0 indicates non-adoption.

[0244] 10) River channel length: The length of the confluence river channel, in km.

[0245] 11) River channel slope: The slope of the confluence river channel, in ‰.

[0246] In this embodiment, the system can automatically identify the series and parallel relationships of cascade reservoirs, perform reservoir flood routing calculations step by step from upstream to downstream based on the topological structure, combine real-time water regime and meteorological forecast data, complete the simulation of joint flood control operation of cascade reservoirs, output the change process of reservoir water levels, the flood discharge process of each reservoir, and the scheduling evaluation results, providing scientific decision-making support for regional flood control.

[0247] As described above, it is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent replacements or changes, and all should be covered within the protection scope of the present invention.

Claims

1. A flood control dispatch simulation method for multi-stage series-parallel cascade reservoirs, characterized in that: The following steps are involved: Step 1: Collection and collation of basic data: Collect basic basin data, reservoir data, reservoir flood control and dispatching procedures, and water and rainfall monitoring station network information of the area to be simulated; Step 2: Consider the topological structure generation and processing of the series-parallel relationship of cascade reservoirs: extract the river network based on the collected basic data, divide the sub-basins, analyze the series-parallel relationship of cascade reservoirs, generate the topological structure of cascade reservoirs, and perform standardized processing; Step 3: Simulation method and model construction of flood control dispatching of cascade reservoirs based on topological structure: Combined with the generated topological structure relationship of cascade reservoirs, sub-basin process calculation, flood control dispatching calculation, and river confluence calculation are performed respectively. The model is constructed based on three-layer nested loops to simulate the inflow flood and flood control calculation process of cascade reservoirs step by step from upstream to downstream; Step 4: Model simulation and scheme evaluation: Set up flood forecasting and joint scheduling schemes, simulate the flood control scheduling process of cascade reservoirs under different schemes, and conduct scheme comparison analysis and effect evaluation based on model simulation results.

2. The flood control dispatch simulation method adapted to multi-stage series-parallel cascade reservoirs according to claim 1 is characterized in that: The basic data of the river basin include: river system maps of the river basin including rivers, lakes and reservoirs, high-precision elevation data and basic data of rivers, lakes and reservoirs; among them, the basic data of reservoirs include: basic data of reservoir characteristic water level, characteristic storage capacity, water level-storage capacity curve, and water level-discharge curve; the water and rainfall monitoring station network information includes: water and rainfall monitoring station network information including rainfall stations, water level stations, flow stations, and hydrological stations and their actual measured data.

3. The flood control dispatch simulation method adapted to multi-stage series-parallel cascade reservoirs according to claim 2 is characterized in that: The second step is to consider the topological structure generation and processing of the series-parallel relationship of the cascade reservoirs, which specifically includes: S201: River network extraction: Based on the high-precision elevation data of the watershed to be simulated and the watershed water system map, hydrological analysis is performed to divide the basic watershed and extract the river network consistent with the real water system; S202: Sub-basin division: Based on the actual distribution of cascade reservoirs in the river network, merge the basic basin boundaries and divide them into several sub-basins; S203: Analysis of the series and parallel relationship of cascade reservoirs: Based on the river network and sub-basin range, the catchment area of ​​each reservoir is clarified, and the series and parallel relationship of cascade reservoirs is identified according to the confluence relationship between upstream and downstream reservoirs; S204: Topology structure generation: Based on the series-parallel relationship of the cascade reservoirs, an association relationship is established for each reservoir with upstream and downstream reservoirs to form a preliminary topology structure, and the calculation level is allocated according to the series-parallel relationship and in the order from upstream to downstream; S205: Standardization processing: data formatting is performed on the initially formed cascade reservoir topology structure, a topology relationship table is constructed, and standardized topology structure data is stored in a database.

4. The flood control dispatch simulation method adapted to multi-stage series-parallel cascade reservoirs according to claim 3 is characterized in that: The step three: constructing a simulation method and model for flood control dispatching of cascade reservoirs based on topological structure, specifically includes: S301: Calculation method for sub-basin flood process: Based on the sub-basin division results and combined with the flood forecasting scheme, the flood forecasting model is used to simulate the flood flow process of each sub-basin. The calculation formula is as follows: In the formula, represents the simulated flow of the mth sub-basin, MODEL flood represents the flood forecasting model, represents the geographical characteristics of the mth sub-basin, represents the meteorological data in the mth sub-basin, β flood represents the flood forecast model parameters; If a sub-basin completely covers the water collection range of the reservoir, the flow process at the outlet section of the sub-basin is the flood process of the reservoir; if a sub-basin only covers a part of the water collection range of the reservoir, the flow process at the outlet section of the sub-basin is the flood process of the corresponding catchment area of ​​the reservoir; S302: Calculation method for flood control dispatch of independent reservoirs: On the basis of the calculation grade allocation results, the reservoirs corresponding to the calculation grade in the topological structure of the cascade reservoirs are extracted, the total inflow of the reservoir corresponding to the current calculation grade is calculated, and combined with the set flood control dispatching scheme, the reservoir flood regulation calculation model is used to simulate the flood control dispatching process of the reservoir corresponding to the current calculation grade, and the reservoir water level change process and the downstream flood discharge process are obtained. The calculation formula is as follows: In the formula, j1 represents the jth reservoir under calculation level 1, represents the total inflow of the j1th reservoir, represents the number of sub-basins corresponding to the j1-th reservoir, represents the simulated flow of the jth reservoir into the sub-basin, represents the outflow of the j1th reservoir, MODEL operation represents the reservoir flood control calculation model, represents the starting water level of the j1th reservoir, represents the water level-storage capacity curve of the j1th reservoir, represents the water level-discharge curve of the j1th reservoir, represents the flood control dispatching plan of the j1th reservoir; S303: Calculation method for river confluence between upper and lower reservoirs: Based on the calculation grade allocation result, the reservoirs corresponding to all calculation grades except the calculation grade of step S302 in the topological structure of the cascade reservoirs are extracted. For a reservoir under the current calculation grade, the downstream flood discharge process of the upper reservoir corresponding to the current reservoir is obtained. The river confluence calculation model is used to simulate the river confluence process from each upper reservoir dam of the current reservoir to the dam of the current reservoir, and the total inflow flow of the current reservoir is calculated. The calculation formula is as follows: In the formula, j k Indicates the calculation of the jth reservoir at level k, k>1, Indicates the jth k The number of upstream reservoirs of the reservoir, Indicates that the jth k The total discharge of the parent reservoir of the reservoir, It means that after the flood discharge from the lth upper reservoir reaches the jth k The flow of the reservoir, MODEL routing represents the river confluence routing model, represents the flood discharge of the lth upper reservoir, and Respectively represent the lth upper reservoir dam down to the jth k The length and slope of the river channel in front of the reservoir dam, β routing Indicates the parameters of the river confluence routing model; S304: Calculation method for flood control dispatch of cascade reservoirs: For the reservoir corresponding to step S303, combined with the set dispatching scheme and the calculated total inflow, the reservoir flood control calculation model is used to simulate the flood control dispatching process of the current reservoir, and the reservoir water level change process and the downstream flood discharge process of the current reservoir are obtained. The calculation formula is as follows: In the formula, j k Indicates the calculation of the jth reservoir under level k, Indicates the jth k The total inflow to the reservoir, Indicates the jth k The simulated flow between the reservoir catchment areas is Indicates the jth k The outflow of the reservoir, Indicates the jth k The starting water level of the reservoir [m], Indicates the jth k The water level-capacity curve of a reservoir, Indicates the jth k The water level-discharge curve of a reservoir, represents the flood control dispatching plan of the jth reservoir; S305: Model construction based on three-layer nested loops: By setting up three-layer nested loops including calculation level loop, reservoir traversal loop and time period iteration loop, the flood inflow and flood control calculation process of cascade reservoirs are simulated time by time, reservoir by reservoir and level by level to realize model construction.

5. The flood control dispatch simulation method adapted to multi-stage series-parallel cascade reservoirs according to claim 4 is characterized in that: S305: Model construction based on three-layer nested loops, including: S3051: Identification of series and parallel relationships of cascade reservoirs: Extract the topological structure of the cascade reservoirs in the area to be simulated from the database, identify the series, parallel and mixed relationships between the cascade reservoirs, and determine the calculation level of each reservoir; S3052: Sub-basin flood process simulation: Calculate the flood flow process of each sub-basin based on the flood forecasting model, and store the simulated sub-basin flood forecast results in the sub-basin flood forecast results database; S3053: Model simulation based on three-layer nested loops: A three-layer loop setting method is used to form an iterative calculation loop with the calculation level as the first level, all reservoirs under the corresponding level as the second level, and all time periods within the simulation period as the third level.

6. The flood control dispatch simulation method adapted to multi-stage series-parallel cascade reservoirs according to claim 5, characterized in that: The model simulation based on three-layer nested loops includes: Taking a reservoir at the current calculation level as the object, based on the downstream flood process of the upstream reservoir corresponding to the current reservoir, the river confluence routing model is used to calculate the flood process of the upstream reservoir reaching the current reservoir dam, and combined with the sub-basin flood process simulation results to obtain the interval inflow flood process of the current reservoir, and determine the inflow flood process of the current reservoir.

7. The flood control dispatch simulation method adapted to multi-stage series-parallel cascade reservoirs according to claim 6, characterized in that: The model construction based on three-layer nested loops also includes: S3054: Based on the simulation results of the model based on the three-layer nested loop, the discharge flow results of the current reservoir are used as input data to provide boundary conditions for the river confluence simulation of the next calculation level reservoir; S3055: After all reservoirs of the current calculation level are traversed, the next calculation level reservoir cycle is entered, and the above process is repeated until all reservoirs of the calculation level are calculated; S3056: When the reservoir cycle of all calculation levels is completed, the water level change process and flood discharge process of each cascade reservoir in the simulation area are output and saved in the reservoir flood control calculation results database.

8. The flood control dispatch simulation method adapted to multi-stage series-parallel cascade reservoirs according to claim 7 is characterized in that: The fourth step, model simulation and solution evaluation, specifically includes the following steps: S401: Basic data review and storage: Based on the collected and sorted basin basic data, reservoir basic data, reservoir flood control dispatching regulations and water and rainfall monitoring station network information, they are manually reviewed, standardized and stored; S402: Modeling preprocessing and storage: Based on the topological structure generation and processing considering the series and parallel relationship of cascade reservoirs, river network extraction, sub-basin division and cascade reservoir topological structure generation are carried out, and standardized processing is carried out and stored; S403: Model selection and parameter storage: Based on the runoff characteristics of the area to be simulated and the completeness of the basic data, the corresponding flood forecasting model, river runoff calculation model, and reservoir flood control calculation model are selected, and the model parameters are determined through parameter calibration; S404: Database configuration: configure the link mode of the database table to complete the database configuration; S405: Scheme setting: For the cascade reservoirs in the area to be simulated, a flood forecasting scheme is set in combination with historical water and rainfall information and forecast rainfall processes, and a joint dispatching scheme is set in combination with the current flood situation of the reservoirs, taking into account the flood control safety of the flood protection area downstream of the reservoirs; S406: receiving parameters and operating the model: determining the operating parameters of the forecast period start time, forecast period length, period length, and warm-up period length, and inputting them into the corresponding flood forecast model, river confluence calculation model, and reservoir flood control calculation model to operate the model; S407: Flood process simulation under a given scheme: simulate the flood process at the outlet section of each sub-basin based on the flood forecasting scheme, and perform data analysis and display; S408: Simulation of the dispatching process under a given scheme: Simulate the joint dispatching process of cascade reservoirs based on the joint dispatching scheme, and perform data analysis and display; S409: By setting different flood forecasting schemes and joint dispatching schemes, the flood process and reservoir dispatching process are simulated respectively, and the scheme comparison analysis and effect evaluation are carried out based on the simulation results.

9. A flood control dispatching simulation system adapted to multi-stage series-parallel cascade reservoirs, applied in the flood control dispatching simulation method adapted to multi-stage series-parallel cascade reservoirs as claimed in claim 8, characterized in that: include: Basic data processing module, used to collect and process basin basic data, reservoir basic data and water and rainfall monitoring station network information; A topology structure generation module is used to analyze the series-parallel relationship of the cascade reservoirs based on the data collected by the basic data processing module, generate the topology of the cascade reservoirs, and output a standardized topology relationship table; The sub-basin flood forecasting module is used to select the corresponding flood forecasting model and calibrate the model parameters according to the sub-basin runoff characteristics, simulate and output the flood flow process at the outlet section of the sub-basin; The reservoir flood control calculation module is used to simulate the reservoir flood inflow process and flood control dispatch process step by step according to the calculation level order based on the topological structure relationship of the cascade reservoirs, calculate the river confluence between the upper and lower reservoirs, and output the reservoir water level change process and downstream flood discharge process of each reservoir; The scheme setting and simulation evaluation module is used to run the model based on the set flood forecasting scheme and joint scheduling scheme, evaluate the flood control scheduling process and effect of cascade reservoirs under the set scheme, generate an operation evaluation report, and provide optimization suggestions for the scheduling scheme.

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