Reservoir forecasting and dispatching integrated method

Abstract

The invention provides a reservoir forecasting and dispatching integrated method. The reservoir forecasting and dispatching integrated method comprises the steps that water catchment units of a reservoir water catchment area are divided according to DEM topographic data; a hydrological model is adopted to simulate the hydrological process of each catchment unit, and the runoff yield of each catchment unit is obtained; constructing a topological relation between an upstream river channel and a reservoir area of the reservoir, and performing simulation based on the runoff by adopting a hydrodynamic model to obtain flow convergence data; constructing a sluice and weir discharge model, setting a reservoir dispatching scheme, and calculating the discharge flow of the reservoir; a reservoir area regulation and storage model is constructed, and the reservoir area water level in the forecasting period is obtained; and pushing a reservoir scheduling scheme based on the reservoir area water level in the forecast period. According to the method, accurate simulation of reservoir forecast scheduling is realized, an effective tool is provided for flood control and disaster reduction and optimal scheduling of water resources, and the method has important practical value.

Description

Technical Field

[0001] The invention relates to the field of information technology, and in particular to a reservoir forecasting and dispatching integrated method. Background Art

[0002] Reservoirs play an important role in river basin flood control, water supply security, irrigation, power generation, ecological protection and landscape value.

[0003] However, the traditional reservoir water space management method has problems such as incomplete coverage, insufficient scheduling and operation decision-making capabilities, and waste of human resources.

[0004] In order to ensure the safe and stable operation of the reservoir and improve the intelligence level of reservoir management and the operation and maintenance efficiency, the present invention provides an integrated reservoir forecasting and scheduling model to form an overall solution for reservoir space management and operation guarantee. Summary of the invention

[0005] The purpose of the present invention is to propose a reservoir forecasting and dispatching integrated method for the reservoir space management and operation guarantee problem.

[0006] The technical solution of the present invention is: The present invention provides a reservoir forecasting and dispatching integrated method, comprising: S1. Divide the catchment area of ​​the reservoir into catchment units according to DEM terrain data; S2. Use a hydrological model to simulate the hydrological process of each catchment unit to obtain the flow yield of each catchment unit; S3, construct the topological relationship between the upstream river channel and the reservoir area, use the hydrodynamic model to simulate based on flow production, and obtain flow inflow data; S4, construct the flood discharge gate and weir discharge model, set the reservoir dispatching plan, and calculate the reservoir discharge flow; S5. Construct a reservoir regulation model to obtain the reservoir water level during the forecast period; S6. Based on the reservoir water level during the forecast period, the reservoir dispatching plan is pushed.

[0007] Furthermore, the division of the water catchment area of ​​the reservoir into water catchment units according to the DEM terrain data in S1 includes: The DEM data was preprocessed, the D8 algorithm was used for flow direction analysis, the catchment area was calculated through cumulative flow analysis, and the catchment units were divided according to the set thresholds, and the terrain and geometric feature data of each unit were extracted.

[0008] Furthermore, the hydrological model is used in S2 to simulate the flow generation and confluence process of each water catchment unit to obtain the flow inflow data of the upstream river channel and the reservoir area of ​​the reservoir, including: S21. Based on the land use type, the soil underlying surface is divided into water surface, building land and dry land; S22, when the underlying surface type is dry land (permeable, including forest land, grassland or other dry land); If the soil is in an unsaturated seepage state, the following formula is used to calculate the soil infiltration rate: ; middle I is the rainfall intensity (mm / hr); If the soil is saturated and a stable seepage is formed, the soil infiltration rate is calculated and the soil infiltration amount at each time step is obtained using the following formula;

[0009] in: f p is the infiltration capacity, in mm / hr, K s is the infiltration conductivity, in mm / hr, M d is the initial saturation difference (volume / volume), S av is the average soil matrix suction (mm), F is the initial soil infiltration (mm), t To calculate the duration.

[0010] S23. When the underlying surface type is water surface or building land, the fixed runoff coefficient is used to calculate the flow rate: ; Where: P is a fixed runoff coefficient, S 0 For initial losses; When the underlying surface type is dry land, the following formula is used to calculate the runoff:

[0011] Where: P is the rainfall, E is the evaporation amount, S For loss, q is the flow rate, and the unit is mm.

[0012] Further, the S3 includes: S31, establishing a topological connection relationship by superimposing the river network vector data with the watershed unit boundary; S32, taking the flow produced by each water-collecting unit as lateral inflow or upstream inflow, and obtaining flow inflow data through a one-dimensional hydrodynamic model.

[0013] Further, the S32 specifically includes: If there is a river network inside the catchment unit or it is located in the reservoir area, the flow produced by the catchment unit will be regarded as the lateral inflow; If there is no river network inside the catchment unit or it is outside the reservoir area, then find the downstream unit connected to the catchment unit, and take the flow of the catchment unit as the upstream inflow of the downstream catchment unit according to the topological connection relationship; The inflow conditions of each catchment unit were taken as boundary conditions, and the one-dimensional hydrodynamic model was used to obtain the flow inflow data of the upstream river channel and reservoir area.

[0014] Further, the S4 includes: Obtain floodgate parameter information and determine whether the flow state is orifice flow or weir flow; Calculate the flow rate, perform weighted averaging on the flow rates calculated from the orifice flow and weir flow, and obtain the final discharge flow rate of the flood discharge gate.

[0015] Furthermore, the obtained flood discharge gate and weir parameter information is used to determine whether the flow state is orifice flow or weir flow: Get the water depth above the lock H u , Total water head on the gate H 0. Water depth under the gate H d , Gate opening e Parameter information; When the reservoir discharge is not controlled by gates, it is judged as free weir flow; when e / H u When it is greater than 0.65, it is judged as weir flow; otherwise, it is hole flow; when H d / H When 0>0.8, it is judged as submerged outflow; otherwise, it is free outflow; when e / H u When >0.60, the flow calculated from the orifice flow and the weir flow is weighted averaged so that the orifice outflow reaches the critical point of the weir outflow as the final flood discharge of the flood gate.

[0016] Through the above judgment results, the specific flow state of the sluice is determined, which is divided into five working conditions: free hole flow, free weir flow, submerged hole flow, submerged weir flow and no flow, and the flow rate is calculated respectively.

[0017] Further, the S5 includes: Obtain terrain elevation information of the reservoir area; Establish a reservoir storage model, solve the storage differential equation, and obtain the reservoir water level during the forecast period Z : Where: Q is the algebraic sum of the inflow and outflow of the storage area, Q o represents the reservoir discharge, Q i Represents the inbound flow, Q e represents the loss flow, including evapotranspiration factors; A ( Z ) is the area of ​​the regulation and storage area corresponding to the water level; t For time.

[0018] Furthermore, S6 includes: According to the reservoir water level in the forecast period, determine whether the discharge of the flood gate needs to be adjusted. If necessary, the optimal scheduling plan is matched based on cluster analysis and Euclidean distance and pushed; Specifically: K-means clustering algorithm is used to cluster the historical operation plans of reservoirs to obtain different types of typical operation plans; The reservoir water level in the current forecast period is compared with the water levels of each typical scheduling scheme, and the alternative scheduling scheme closest to the current water level is found by calculating the Euclidean distance.

[0019] Furthermore, the method also includes: selecting observation data of rainfall, water level and flow of typical flood events to calibrate the parameters of the hydrological model, including: using the Nash-Sutcliffe coefficient and the coefficient of determination R2 as evaluation indicators, and adjusting the hydrological model runoff parameters and river roughness parameters to achieve the best degree of agreement between the simulated values ​​and the measured values.

[0020] Beneficial effects of the present invention: The present invention discloses an integrated method for reservoir forecasting and dispatching. The method divides the water catchment unit based on DEM terrain data; considers the spatial distribution difference of land use types, adopts a hydrological model to simulate the flow generation and convergence process; constructs the topological relationship between the upstream river channel of the reservoir and the reservoir area, adopts a hydrodynamic model to obtain the flow inflow data; constructs a reservoir regulation model to simulate the water level change in the reservoir area, and pushes the reservoir dispatching plan. The method of the present invention realizes the accurate simulation of reservoir forecasting and dispatching, provides an effective tool for flood prevention and disaster reduction and water resources optimization dispatching, and has important practical value.

[0021] The present invention tightly couples the runoff generation and confluence model with the hydrodynamic model to realize the simulation of the entire process of rainfall-runoff generation and confluence-reservoir scheduling; key parameters are calibrated through typical flood event data, and indicators such as the Nash coefficient are used to evaluate and optimize the model accuracy.

[0022] Other features and advantages of the present invention will be described in detail in the following detailed description. DETAILED DESCRIPTION

[0023] The preferred embodiments of the present invention will be described in more detail below. It should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0024] The present invention provides a reservoir forecasting and dispatching integrated method, comprising: S1. Preprocess the DEM data, use the D8 algorithm to analyze the flow direction, calculate the catchment area through cumulative flow analysis, divide the catchment units according to the set threshold, and extract the topographic and geometric feature data of each unit.

[0025] S2. Use the hydrological model to simulate the hydrological process of each catchment unit to obtain the runoff of each catchment unit; specifically including: S21. Based on the land use type, the soil underlying surface is divided into water surface, building land and dry land; S22. When the underlying surface type is dry land, the dry land is permeable, including forest land, grassland or other dry land; If the soil is in an unsaturated seepage state, the following formula is used to calculate the soil infiltration rate: ; middle I is the rainfall intensity (mm / hr);

[0026] If the soil is saturated and a stable seepage is formed, the soil infiltration rate is calculated and the soil infiltration amount at each time step is obtained using the following formula; ; in: f p is the infiltration capacity, in mm / hr, K s is the infiltration conductivity, in mm / hr, M d is the initial saturation difference (volume / volume), S av is the average soil matrix suction (mm), F is the initial soil infiltration (mm), t To calculate the duration.

[0027] S23. When the underlying surface type is water surface or building land, the fixed runoff coefficient is used to calculate the flow rate;

[0028] Where: P is a fixed runoff coefficient, S 0 For initial losses; When the underlying surface type is dry land, the following formula is used to calculate the runoff:

[0029] Where: P is the rainfall, E is the evaporation amount, S For loss, q is the flow rate, and the unit is mm.

[0030] S3. Construct the topological relationship between the upstream river channel and the reservoir area, use the hydrodynamic model to simulate based on flow production, and obtain flow inflow data, including: S31, establishing a topological connection relationship by superimposing the river network vector data with the watershed unit boundary; S32, taking the flow produced by each water collection unit as lateral inflow or upstream inflow, and obtaining flow inflow data through a one-dimensional hydrodynamic model; If there is a river network inside the catchment unit or it is located in the reservoir area, the flow produced by the catchment unit will be regarded as the lateral inflow; If there is no river network inside the catchment unit or it is outside the reservoir area, then find the downstream unit connected to the catchment unit, and take the flow of the catchment unit as the upstream inflow of the downstream catchment unit according to the topological connection relationship; The inflow conditions of each catchment unit were taken as boundary conditions, and the one-dimensional hydrodynamic model was used to obtain the flow inflow data of the upstream river channel and reservoir area.

[0031] S4. Obtain parameter information of the flood discharge gate, determine whether the flow state is hole flow or weir flow; calculate the flow rate, perform weighted averaging on the flow rates calculated for the hole flow and weir flow, and obtain the final flood discharge flow rate of the flood discharge gate.

[0032] S5. Construct a reservoir regulation model to obtain the reservoir water level during the forecast period; including: Obtain terrain elevation information of the reservoir area; Establish a reservoir storage model, solve the storage differential equation, and obtain the reservoir water level during the forecast period Z :

[0033] Where: Q is the algebraic sum of the inflow and outflow of the storage area, Q o represents the reservoir discharge, Q i Represents the inbound flow, Q e represents the loss flow, including evapotranspiration factors; A ( Z ) is the area of ​​the regulation and storage area corresponding to the water level; t For time.

[0034] S6. Based on the reservoir water level during the forecast period, the reservoir dispatching plan is pushed.

[0035] In one example, the obtained flood discharge gate and weir parameter information is used to determine whether the flow state is hole flow or weir flow: Get the water depth above the lock H u , Total water head on the gate H 0. Water depth under the gate H d , Gate opening e Parameter information; When the reservoir discharge is not controlled by gates, it is judged as free weir flow; when e / H u When it is greater than 0.65, it is judged as weir flow; otherwise, it is hole flow; when H d / H When 0>0.8, it is judged as submerged outflow; otherwise, it is free outflow; when e / H u When >0.60, the flow calculated from the orifice flow and the weir flow is weighted averaged so that the orifice outflow reaches the critical point of the weir outflow as the final flood discharge of the flood gate.

[0036] Through the above judgment results, the specific flow state of the sluice is determined, which is divided into five working conditions: free hole flow, free weir flow, submerged hole flow, submerged weir flow and no flow. The flow rate is calculated using the following formulas respectively.

[0037] (a) No flow ; (b) Free hole flow ; (c) Free weir flow ; (d) Submerged hole flow ; (e) Submerged weir flow ; Where: M 1. M 2. M 3. M 4 are the comprehensive flow coefficients under free hole flow, free weir flow, submerged hole flow and submerged weir flow conditions respectively; B w The total clear width of the gate opening; Q i and Q i+1 They are i and iFlow rate at section +1.

[0038] In one example, based on the reservoir water level during the forecast period, it is determined whether the discharge of the flood gate needs to be adjusted. If necessary, the optimal scheduling solution is matched based on cluster analysis and Euclidean distance and pushed; Specifically: K-means clustering algorithm is used to cluster the historical operation plans of reservoirs to obtain different types of typical operation plans; The reservoir water level in the current forecast period is compared with the water levels of each typical scheduling scheme, and the alternative scheduling scheme closest to the current water level is found by calculating the Euclidean distance.

[0039] In one example, the method further includes: selecting observation data of rainfall, water level, and flow of typical flood events to calibrate the parameters of the hydrological model, including: using the Nash-Sutcliffe coefficient and the coefficient of determination R 2 As evaluation indicators, the runoff parameters and channel roughness parameters of the hydrological model are adjusted to achieve the best agreement between the simulated values ​​and the measured values.

[0040] According to the relevant specifications for model calibration and verification, the measured rainfall, water level and flow data of more than three typical rainstorms were selected; the Nash-Sutcliffe coefficient NSE and the coefficient of determination were used. R 2 As an evaluation index, the effectiveness of the model is evaluated; the accuracy of the simulation results is improved by adjusting the hydrological model parameters such as the runoff coefficient, soil infiltration rate, and the hydrodynamic model parameters such as the river roughness, gate, and weir comprehensive flow coefficient in the model; if the simulated value is close to the measured order of magnitude and process trend, the Nash-Sutcliffe coefficient and determination coefficient are determined. R 2 Whether the requirements are met; it is usually stipulated that the maximum water level error between the verification result and the actual flood is no more than 15cm, and the Nash efficiency coefficient of the predicted water level is greater than or equal to 0.7, and the determination coefficient R 2 If the value is greater than 0.8 and the relative error is less than or equal to 10%, the model accuracy is high and can be verified through calibration. The accuracy index can be adjusted according to the actual situation of the calculation object and specific business needs. By continuously adjusting and optimizing the model parameters, the degree of agreement between the simulated value and the measured value is optimized and the model calibration is completed.

[0041] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A reservoir forecasting and dispatching integrated method, characterized in that: include: S1. Divide the catchment area of ​​the reservoir into catchment units according to DEM terrain data; S2. Use a hydrological model to simulate the hydrological process of each catchment unit to obtain the flow yield of each catchment unit; S3, construct the topological relationship between the upstream river channel and the reservoir area, use the hydrodynamic model to simulate based on flow production, and obtain flow inflow data; S4, construct the flood discharge gate and weir discharge model, set the reservoir dispatching plan, and calculate the reservoir discharge flow; S5. Construct a reservoir regulation model to obtain the reservoir water level during the forecast period; S6. Based on the reservoir water level during the forecast period, the reservoir dispatching plan is pushed.

2. The reservoir forecasting and dispatching integrated method according to claim 1, characterized in that: In S1, the water catchment area of ​​the reservoir is divided into water catchment units according to the DEM terrain data, including: The DEM data was preprocessed, the D8 algorithm was used for flow direction analysis, the catchment area was calculated through cumulative flow analysis, and the catchment units were divided according to the set thresholds, and the terrain and geometric feature data of each unit were extracted.

3. The reservoir forecasting and dispatching integrated method according to claim 1 is characterized in that In S2, a hydrological model is used to simulate the flow generation and confluence process of each catchment unit to obtain the flow inflow data of the upstream river channel and reservoir area of ​​the reservoir, including: S21. Based on the land use type, the soil underlying surface is divided into water surface, building land and dry land; S22, the lower surface type is dry land; If the soil is in an unsaturated seepage state, the following formula is used to calculate the soil infiltration rate: ; middle I is the rainfall intensity (mm / hr); If the soil is saturated and a stable seepage is formed, the soil infiltration rate is calculated and the soil infiltration amount at each time step is obtained using the following formula; ; in: f p is the infiltration capacity, in mm / hr, K s is the infiltration conductivity, in mm / hr, M d is the initial saturation difference, S av is the average soil matrix suction, unit: mm, F is the initial soil infiltration, in mm, t To calculate duration; S23. When the underlying surface type is water surface or building land, the fixed runoff coefficient is used to calculate the flow rate: ； Where: Ψ is a fixed runoff coefficient, S 0 For initial losses; When the underlying surface type is dry land, the following formula is used to calculate the runoff: ； Where: P is the rainfall, E is the evaporation amount, S For loss, q is the flow rate, and the unit is mm.

4. The reservoir forecasting and dispatching integrated method according to claim 1 is characterized in that The S3 includes: S31, establishing a topological connection relationship by superimposing the river network vector data with the watershed unit boundary; S32, taking the flow produced by each water-collecting unit as lateral inflow or upstream inflow, and obtaining flow inflow data through a one-dimensional hydrodynamic model.

5. The reservoir forecasting and dispatching integrated method according to claim 4 is characterized in that The S32 specifically includes: If there is a river network inside the catchment unit or it is located in the reservoir area, the flow produced by the catchment unit will be regarded as the lateral inflow; If there is no river network inside the catchment unit or it is outside the reservoir area, then find the downstream unit connected to the catchment unit, and take the flow of the catchment unit as the upstream inflow of the downstream catchment unit according to the topological connection relationship; The inflow conditions of each catchment unit were taken as boundary conditions, and the one-dimensional hydrodynamic model was used to obtain the flow inflow data of the upstream river channel and reservoir area.

6. The reservoir forecasting and dispatching integrated method according to claim 1, characterized in that: The S4 includes: Obtain floodgate parameter information and determine whether the flow state is orifice flow or weir flow; Calculate the flow rate, perform weighted averaging on the flow rates calculated from the orifice flow and weir flow, and obtain the final discharge flow rate of the flood discharge gate.

7. The reservoir forecasting and dispatching integrated method according to claim 6, characterized in that: The obtained flood discharge gate and weir parameter information is used to determine whether the flow state is hole flow or weir flow: Get the water depth above the lock H u , Total water head on the gate H 0. Water depth under the gate H d , Gate opening e Parameter information; When the reservoir discharge is not controlled by gates, it is judged as free weir flow; when e / H u When it is greater than 0.65, it is judged as weir flow; otherwise, it is hole flow; when H d / H When 0>0.8, it is judged as submerged outflow; otherwise, it is free outflow; when e / H u When >0.60, the flow calculated from the orifice flow and the weir flow is weighted averaged so that the orifice outflow reaches the critical point of the weir outflow as the final flood discharge of the flood gate.

8. The reservoir forecasting and dispatching integrated method according to claim 1, characterized in that: The S5 includes: Obtain terrain elevation information of the reservoir area; Establish a reservoir storage model, solve the storage differential equation, and obtain the reservoir water level during the forecast period Z : ； Where: Q is the algebraic sum of the inflow and outflow of the storage area, Q o represents the reservoir discharge, Q i Represents the inbound flow, Q e represents the loss flow, including evapotranspiration factors; A ( Z ) is the area of ​​the regulation and storage area corresponding to the water level; t For time.

9. The reservoir forecasting and dispatching integrated method according to claim 1, characterized in that S6 include: According to the reservoir water level in the forecast period, determine whether the discharge of the flood gate needs to be adjusted. If necessary, the optimal scheduling plan is matched based on cluster analysis and Euclidean distance and pushed; Specifically: K-means clustering algorithm is used to cluster the historical operation plans of reservoirs to obtain different types of typical operation plans; The reservoir water level in the current forecast period is compared with the water levels of each typical scheduling scheme, and the alternative scheduling scheme closest to the current water level is found by calculating the Euclidean distance.

10. The reservoir forecasting and dispatching integrated method according to claim 1, characterized in that: The method also includes: selecting observation data of rainfall, water level and flow of typical flood events to calibrate the parameters of the hydrological model, including: using the Nash-Sutcliffe coefficient and the coefficient of determination R 2 As evaluation indicators, the runoff parameters and channel roughness parameters of the hydrological model are adjusted to achieve the best agreement between the simulated values ​​and the measured values.

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