Multi-region flood control scheduling calculation method coupled with downstream river channel flood evolution of reservoir

Abstract

The application discloses a kind of multi-zone flood control scheduling calculation methods of coupling reservoir downstream river course flood evolution, according to the flood control scheduling demand of different flood control protection zones downstream of reservoir, in combination with the flood control task of reservoir, scheduling regulation, engineering characteristics, the maximum flood control storage capacity reserved for different zones, and river course flood propagation characteristics, downstream different flood control sites forecast flow process, the discharge flow of reservoir is determined when downstream multi-zone is carried out flood control scheduling in current period comprehensively.According to the discharge flow process of reservoir early stage and the discharge flow determined in current period, the flow process of each flood control site downstream is recalculated under the current storage operation of reservoir, the forecast flow of each flood control site is updated in turn, the discharge flow of reservoir in next period is determined again, and the flood control scheduling calculation of whole flood is completed by rolling calculation, with the advantages of high calculation accuracy, small flood control storage capacity, high flood control benefit per unit of storage capacity.

Description

Technical Field

[0001] This invention belongs to the field of water conservancy and hydropower technology, specifically referring to a multi-regional flood control scheduling calculation method that couples the evolution of downstream river channels of a reservoir. Background Technology

[0002] Reservoir flood control scheduling refers to the planned regulation of inflow floods into the reservoir, based on hydrological forecasts and under the premise of ensuring dam safety. This aims to improve the spatiotemporal distribution of natural runoff within the basin, thereby preventing flood disasters and protecting the lives and property of people in the reservoir area and downstream flood protection zones. When there are multiple flood protection zones downstream of a reservoir, a crucial issue to be addressed in multi-regional flood control scheduling is how to fully utilize the reservoir's flood control function and scientifically and rationally determine the reservoir's discharge flow in the future, ensuring both the reservoir's own flood control safety and efficient coordination of the flood control needs of multiple downstream areas to maximize flood control benefits.

[0003] Currently, reservoir flood control scheduling calculations primarily rely on forecasted flows from downstream flood control stations and along the river's course. Considering the flood propagation time from the reservoir to these stations, and employing methods such as staggered scheduling, the reservoir's discharge flow is directly determined for future time periods. However, this method lacks flood evolution calculations, failing to fully reflect the stabilizing effect of reservoir discharge on the flow reaching downstream flood control stations. Furthermore, in multi-regional flood control scheduling, it struggles to capture the unique flood evolution characteristics of different downstream areas. Moreover, in real-time scheduling, the reservoir's discharge flow in previous periods influences the forecasted flow at downstream flood control stations in subsequent periods. Therefore, flood control scheduling needs to couple with river flood evolution. Within each scheduling period, the forecasted flow at downstream flood control stations must be calculated continuously based on the reservoir's discharge flow in previous periods, and the current reservoir discharge flow must be recalculated according to the new forecasted flow.

[0004] Current flood control scheduling directly provides the reservoir's discharge flow for the foreseeable future based on downstream forecast flow patterns. This approach fails to consider the impact of earlier scheduling on later forecast flows, making it difficult to accurately determine the reservoir's discharge flow pattern. Furthermore, while some studies construct optimized scheduling models to provide the reservoir's discharge flow for a specific period, they do not employ the scheduling methods used in reservoir planning or design validation. This fails to adequately coordinate scheduling constraints such as the upper limit of flood control capacity reserved for different downstream protection areas when addressing multi-regional flood control. There is an urgent need to effectively combine multi-regional flood control scheduling calculations with flood evolution calculations while adhering to reservoir scheduling regulations, thereby maximizing the utilization of limited flood control capacity. Therefore, in flood control scheduling for multiple regions, it is necessary to consider constraints such as the upper limit of reserved flood control capacity, based on reservoir scheduling regulations, and to couple multi-regional flood control scheduling with the flood evolution of downstream rivers. This involves conducting rolling calculations on a time-by-time basis for the reservoir flood control scheduling process and the downstream multi-regional forecast flow process, thereby achieving an effective combination of multi-regional flood control scheduling calculations and flood evolution calculations, and reasonably determining the reservoir's discharge flow to maximize flood control benefits. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of the prior art by proposing a multi-regional flood control scheduling calculation method that couples the evolution of floodwaters in the downstream river channel of a reservoir, so as to meet the needs of accurate calculation for multi-regional flood control scheduling.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A multi-regional flood control scheduling calculation method coupled with the evolution of floodwaters in the downstream channel of a reservoir includes the following steps:

[0008] (1) Collect basic data on reservoir flood control scheduling and identify different flood protection areas downstream of the reservoir;

[0009] (2) Identify the flood control stations, dispatch targets, and dispatch methods corresponding to each flood protection area. Among them, the flood control station S corresponding to the j-th flood protection area is... j j = 1, 2, ..., m, where m is the total number of flood protection areas, m ≥ 2; flood control stations S j The corresponding scheduling objective is to control the peak flow at each flood control station by impounding floodwaters through reservoirs, ensuring that it does not exceed the safe discharge capacity QF of the river channel. j ;

[0010] (3) Calculate the flood control flow rate QR for the i-th time period of the flood event. Taking into account the upper limit of the flood control capacity reserved by the reservoir for each flood protection area and the scheduling constraints of the reservoir, determine the outflow rate QR for the i-th time period. i Where i = 1, 2, ..., N, N is the total number of periods of the flood event, and N ≥ 1;

[0011] (4) Based on the reservoir's outflow process in the early stage, calculate the downstream river flood evolution and determine the new forecast flow process of each flood control station downstream after the reservoir's operation.

[0012] (5) Determine whether it is the end of the flood period. If not, let period i = i + 1 and repeat steps (3) and (4) to perform flood regulation calculation. If yes, the flood regulation calculation for the flood is completed.

[0013] Preferably, in step (1), the basic data includes the reservoir's scheduling procedures, water level and reservoir capacity curves, discharge capacity curves, flood control limit water level, flood control high water level, maximum daily variation of reservoir water level, maximum / minimum discharge flow of the reservoir to meet scheduling needs, upper limit of flood control storage capacity reserved by the reservoir for each flood protection area, propagation time of the reservoir discharge flow to the downstream flood protection area, flood control scheduling methods of the reservoir for different downstream flood protection areas, and design floods of different frequencies.

[0014] Preferably, step (3) includes the following steps:

[0015] (3.1) In accordance with the reservoir operation regulations and the operation targets of each flood control station, flood control calculations are performed for the i-th time period of this flood event to obtain the target outflow of the reservoir when conducting flood control operations for each downstream flood protection area; among which, the target outflow of the reservoir when conducting flood control operations for the j-th flood protection area is QR. j,i ;

[0016] (3.2) Combine the upper limit of flood control storage capacity V reserved by the reservoir for each flood protection area j Calculate the maximum allowable water storage capacity QM of the reservoir for flood control scheduling in all flood protection areas during the i-th time period. j,i ;

[0017] (3.3) When considering other reservoir scheduling objectives in the overall scheduling procedure, the constraints are determined as follows: When multi-regional flood control scheduling is implemented, the actual outflow QR of the reservoir in the i-th time period is... i .

[0018] Preferably, step (3.1) includes the following steps:

[0019] (3.1.1) By constructing a system connecting the reservoir to each flood control station S j Based on the river flood evolution model, when the upstream reservoir's intercepted flow is QC, after the river flood evolution flattening, the downstream flood control stations S j Maximum reduction in forecast flow QD j and the TF corresponding to the maximum reduction amount j QC refers to the flood control capacity of a reservoir, which determines the level of floodwater it can hold.

[0020] (3.1.2) Analysis yields the values ​​of S for each flood control station. j The hydrological forecast period is TP j The hydrological forecast period for each flood control station is determined to be no less than the flood propagation time from the reservoir to the flood control station, i.e., TP. j ≥TF j ;

[0021] (3.1.3) Obtain the S values ​​of each flood control station. j During the TF period j Forecast flow Then the reservoir is the flood control control station S in the i-th time period. j The target discharge flow rate for flood control scheduling is: Among them: QIN i Let be the inflow to the reservoir during the i-th time period; calculate the target outflow for flood control scheduling at all flood control control stations during the i-th time period.

[0022] Preferably, step (3.1.1) includes the following steps:

[0023] (a) Calculations were performed using the Muskingen channel flood evolution model: Q′ t =C0Q t +C1Q t-1 +C2Q′ t-1 Q t Q t-1 Let Q′ represent the reservoir outflow at time t and t-1, respectively. t Q′ t-1 The flow rates at the downstream flood control stations for time periods t and t-1 are calculated respectively, and C0, C1, and C2 are the river evolution coefficients.

[0024] (b) Subtract the newly added impounded flow QC from the original outflow from the reservoir, and recalculate the forecast flow sequence for each downstream flood control station;

[0025] (c) Compare the forecast flow processes of downstream flood control stations before and after reservoir impoundment, and determine the maximum reduction in flow at downstream flood control stations and the time period after reservoir impoundment.

[0026] Preferably, in step (3.2), the upper limit of the flood control storage capacity V reserved by the reservoir for each flood protection area is considered. j Calculate the maximum allowable water storage capacity QM of the reservoir for flood control scheduling at each flood control station in the i-th time period. j,i It is calculated using the following formula:

[0027] When QR x =QR j,x At that time, F(QR)x QR j,x ) = 1; when QR x ≠QR j,x At that time, F(QR) x QR j,x ) = 0; where ΔH is the time period length.

[0028] Preferably, in step (3.3), the maximum allowable interception capacity QM obtained in step (3.2) is first considered. j,i Recalculate the new target outflow from the reservoir: QR j,i =Max(QR) j,i ,QIN i -QM j,i Then the outflow rate QR from the reservoir in the i-th time period is... i =Min(Max(Min(QR) 1,i QR 2,i QR 3,i ,…,QR j,i ,…,QR m,i ),Q min,i ),Q max,i ); where: Q min,i According to the scheduling procedures, Q represents the minimum allowable discharge flow of the reservoir in time period i. max,i According to the scheduling procedures, this is the maximum allowable discharge flow of the reservoir in the i-th time period.

[0029] Preferably, in step (4), the outflow process of the reservoir in the early stage and the outflow QR of the reservoir in the i-th time period determined in step (3) are combined. i By calculating the flood evolution in the downstream river channel, the new forecast flow process for each downstream flood control station can be obtained.

[0030] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0031] This invention presents a multi-regional flood control scheduling calculation method that couples the flood evolution of downstream river channels. Applicable to reservoirs with multi-regional flood control tasks, this method comprehensively determines the reservoir's discharge flow for the current time period by combining constraints such as reservoir scheduling regulations, boundary conditions such as hydrological forecasts, and hydrological conditions such as flood propagation. Through a coupled river flood evolution calculation model, the reservoir's discharge flow is calculated on a rolling basis for each time period, updating the forecast flow process of different downstream flood control stations in real time, and using this to determine the reservoir's outflow for the next time period. From the perspective of flood control scheduling accuracy, this method not only fully considers the flood control needs of different areas downstream of the reservoir and the flattening characteristics of flood propagation to different areas, but also calculates the forecast flow of downstream flood control stations on a rolling basis for each time period, significantly improving the accuracy of reservoir interception flow calculations for each time period during flood control scheduling. From the perspective of the rationality of flood control scheduling calculations, under the premise of meeting reservoir scheduling regulations, this invention effectively combines and integrates the upper limit of flood control capacity reserved for each region, flood control scheduling methods, other scheduling constraints, and river flood evolution, ensuring the rationality of the overall calculation results during real-time reservoir scheduling. From the perspective of overall calculation effect, this invention can reduce ineffective interception and storage in flood control scheduling, reduce the amount of flood control capacity used, maximize the flood control benefit per unit capacity, and improve the precision of reservoir scheduling decisions. It also helps to fully coordinate the flood control needs and inflow characteristics of multiple downstream areas of the reservoir, improve the flood control safety of different areas, and effectively ensure the safety of people's lives and property. Attached Figure Description

[0032] Figure 1 This is a flowchart illustrating the principle of the multi-regional flood control scheduling calculation method for coupled downstream river flood evolution of the present invention.

[0033] Figure 2 This diagram compares the calculation approaches of the multi-regional flood control scheduling calculation method for coupled downstream river flood evolution in this invention with those for uncoupled downstream river flood evolution.

[0034] Figure 3 This is a comparison diagram of the entire flood outflow process in an embodiment of the present invention. Detailed Implementation

[0035] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings, but these descriptions do not constitute a limitation of the present invention and are merely illustrative. Furthermore, the advantages of the present invention will become clearer and easier to understand by explaining them.

[0036] This invention provides a multi-regional flood control scheduling calculation method coupled with the evolution of downstream river floods. The specific calculation process is as follows: Based on the flood control scheduling needs of different regions downstream of the reservoir and the maximum reserved flood control capacity, combined with the reservoir's own flood control tasks, scheduling procedures, engineering characteristics, river flood propagation characteristics, and the forecast flow processes of different downstream flood control control stations, the current time period is comprehensively determined as the reservoir's discharge flow when multiple downstream regions conduct flood control scheduling. Based on the reservoir's previous discharge flow process and the determined discharge flow for the current time period, a river flood evolution calculation model is coupled to recalculate the flow process of each downstream flood control control station under the current reservoir interception operation. The forecast flow of each flood control control station is updated sequentially, and the reservoir's discharge flow for the next time period is re-determined. This rolling calculation continues until the flood control scheduling calculation for the entire flood is completed.

[0037] like Figure 1 As shown, the present invention provides a multi-regional flood control scheduling calculation method that couples the evolution of floodwaters in the downstream channel of a reservoir, comprising the following steps:

[0038] (1) Collect basic data on reservoir flood control scheduling, and clarify the different flood protection areas downstream of the reservoir and the upper limit of the flood control capacity reserved by the reservoir for each flood protection area;

[0039] The basic data includes the reservoir's operation procedures, water level and storage capacity curves, discharge capacity curves, flood control limit water level, flood control high water level, maximum daily variation of reservoir water level, maximum / minimum discharge flow of the reservoir to meet downstream navigation and other needs, upper limit of flood control storage capacity reserved by the reservoir for each flood protection area, propagation time of reservoir discharge flow to downstream flood protection areas, flood control operation methods of the reservoir for different downstream flood protection areas, and design floods of different frequencies.

[0040] (2) Considering the geographical and economic conditions of each flood protection area, determine the flood control stations, dispatch targets, and dispatch methods corresponding to each flood protection area; among them, the flood control station corresponding to the j-th flood protection area is S. j j = 1, 2, ..., m, where m is the total number of flood protection areas, m ≥ 2; flood control stations S j The corresponding scheduling objective is to control the peak flow at each flood control station by impounding floodwaters through reservoirs, ensuring that it does not exceed the safe discharge capacity QF of the river channel. j ;

[0041] This mainly involves analyzing the geographical conditions, flood control engineering layout, population and economic distribution, distribution of important buildings along the river, river flow characteristics, hydrological station layout, and long-term data accumulation of each flood protection area to comprehensively determine the key hydrological stations that can characterize the flood control safety of the flood protection area. Based on the reservoir's own flood control tasks and the flood control needs of different areas, combined with the river's flow capacity and dike construction, the maximum flood control capacity reserved by the upstream reservoir for different protection areas, and the specific scheduling objectives and methods of the upstream reservoir for different flood control stations are determined. The scheduling objective is that when the area encounters a design flood of a certain frequency, the upstream reservoir will use the corresponding flood control scheduling method to ensure that the peak flow of the flood control station does not exceed the river's safe discharge capacity QF. j .

[0042] (3) Calculate the flood control flow rate QR for the i-th time period of the flood event. Taking into account the upper limit of the flood control capacity reserved by the reservoir for each flood protection area and the scheduling constraints of the reservoir, determine the outflow rate QR for the i-th time period. i i = 1, 2, ..., N, where N is the total number of time periods of this flood event, and N ≥ 1;

[0043] Flood control calculations were performed for the i-th time period of this flood event, taking into account the upper limit of the flood control storage capacity V reserved by the reservoir for each flood protection area. j Taking into account the reservoir's scheduling requirements for power generation, navigation, and ecology, including the maximum and minimum outflow rates and the maximum daily fluctuation of the reservoir water level, the reservoir outflow rate QR for this period is obtained. i ;

[0044] (3.1) According to the reservoir's scheduling method for downstream flood protection areas, combined with the flood control station S j The predicted flow rate was used to perform multiple flood control calculations, resulting in the target outflow rate QR of the reservoir when conducting flood control scheduling for each downstream flood protection area. j,i ;

[0045] (3.1.1) Construct flood control stations S from the reservoir to the downstream areas. j The river flood evolution model calculates the downstream flood control stations S after the river flood evolution flattening when the upstream reservoir impoundment flow is QC. j Maximum reduction in forecast flow QD j and the TF corresponding to the maximum reduction amount j QC is the level of floodwater interception determined based on the flood control capacity of the reservoir.

[0046] (a) Constructing the Muskingan model for river flood evolution calculations: Q′ t =C0Q t +C1Q t-1 +C2Q′ t-1 Q tQ t-1 Let Q′ represent the reservoir outflow at time t and t-1, respectively. t Q′ t-1 The flow rates at the downstream flood control stations for time periods t and t-1 are calculated respectively, and C0, C1, and C2 are the river evolution coefficients.

[0047] (b) Make the reservoir outflow rate Q t =Q t -QC, recalculate S for downstream flood control stations. j Forecast flow process sequence {QP j,1 QP j,2 ,...,QP j,i ,...,QP j,N};

[0048] (c) Compare the forecast flow processes of each flood control station before and after reservoir impoundment, and determine the maximum flow reduction QD at each downstream flood control station after reservoir impoundment. j and the time period TF j ;

[0049] (3.1.2) To support flood control scheduling of the reservoir within the effective hydrological forecast period, it is necessary to analyze and obtain the hydrological forecast period (TP) for each flood control station. j The hydrological forecast period for each flood control station is determined to be no less than the flood propagation time from the reservoir to the flood control station, i.e., TP. j ≥TF j ;

[0050] (3.1.3) Obtain the S values ​​of each flood control station. j In the time period TF j Forecast flow Then the reservoir has different flood control stations S in the i-th time period. j Target discharge flow rate for flood control scheduling

[0051] Among them: QIN i Let be the inflow to the reservoir during the i-th time period; calculate the target outflow for flood control scheduling at all flood control control stations during the i-th time period.

[0052] (3.2) Combine the upper limit of flood control storage capacity V reserved by the reservoir for each flood protection area j Calculate the maximum allowable water storage capacity QM of the reservoir for flood control scheduling at each flood control station in the i-th time period. j,i It is calculated using the following formula: When QR x =QR j,x At that time, F(QR) x QR j,x) = 1; when QR x ≠QR j,x At that time, F(QR) x QR j,x ) = 0; where ΔH is the time period length;

[0053] (3.3) When considering other reservoir scheduling objectives in the overall scheduling procedure, the constraints are determined as follows: When multi-regional flood control scheduling is implemented, the actual outflow QR of the reservoir in the i-th time period is... i First, it is necessary to combine the maximum allowable storage capacity QM obtained in step (3.2). j,i Recalculate the new target outflow from the reservoir: QR j,i =Max(QR) j,i ,QIN i -QM j,i Then the outflow from the reservoir in the i-th time period is:

[0054] QR i =Min(Max(Min(QR) 1,i QR 2,i QR 3,i ,…,QR j,i ,…,QR m,i ),Q min,i ),Q max,i );

[0055] Among them, Q min,i To determine the minimum allowable discharge flow of the reservoir in time period i, considering the scheduling constraints such as power generation, navigation, and ecological considerations stipulated in the scheduling regulations; Q max,i To determine the maximum allowable discharge flow of the reservoir in the i-th time period, considering the scheduling constraints such as the maximum discharge capacity and the maximum daily variation of the reservoir water level as specified in the scheduling regulations;

[0056] (4) Based on the reservoir's outflow process in the early stage, calculate the downstream river flood evolution and determine the new forecast flow process of each flood control station downstream after the reservoir's operation.

[0057] The river flood evolution calculation model from the reservoir to the downstream flood control station is the same as that in steps (3.1.1) (a) and (b). This is combined with the reservoir's early outflow process and the outflow QR of the reservoir in the i-th time period determined in step (3). i By calculating the flood evolution in the downstream river channel, the new forecast flow process for each downstream flood control station can be obtained.

[0058] (5) Determine whether it is the end of the flood period. If not, let period i = i + 1 and repeat steps (3) and (4) to perform flood regulation calculation. If yes, the flood regulation calculation for the flood is completed.

[0059] Example 1

[0060] Taking a reservoir as an example, the calculation of multi-regional flood control scheduling for a downstream river section is performed by coupling the flood evolution of the downstream river channel. This includes the following steps:

[0061] Step 1: Collect basic data on flood control scheduling of the reservoir and clarify the flood protection area involved downstream of the reservoir.

[0062] First, characteristic curves such as water level-capacity curve and discharge capacity curve of the reservoir were collected. The flood control limit water level of the reservoir is 370m, the flood control high water level is 380m, the maximum daily water level fluctuation is 2m, and the minimum discharge flow of the reservoir to meet the downstream navigation demand is approximately 1700m³. 3 / s, according to the reservoir's own flood control tasks, there are three main flood protection areas involved in a certain section of the downstream river. The propagation time of the reservoir's outflow to flood protection area 1, flood protection area 2, and flood protection area 3 is about 3h, 19h, and 32h, respectively. The flood control scheduling methods for flood protection area 1, flood protection area 2, and flood protection area 3 are respectively the flood control scheduling methods of intercepting base flow and compensating for controlled storage, equal storage volume, and compensating for controlled storage.

[0063] Step 2: Determine the control stations and flood control scheduling targets that characterize the flood control safety of each region.

[0064] Based on an analysis of the flood control areas, existing flood control layout, distribution of important structures, hydrological station locations, and river flow characteristics of flood protection areas 1, 2, and 3, the key control hydrological stations representing flood control safety for these areas were determined to be flood control control stations S1, S2, and S3, respectively. The upstream reservoirs have a maximum reserved flood control capacity of 910 million m³ for each of the different flood protection areas. 3 1.46 billion m 3 2.96 billion m 3 Taking into account factors such as river flow capacity and dike construction, the specific scheduling objective for flood protection area 1 is: when encountering a 50-year design flood, the peak flow at flood control station S1 should not exceed 51,000 m³ / h. 3 / s; The specific scheduling objective for flood protection area 2 is: when encountering a 50-year design flood, the peak flow at flood control station S2 should not exceed 52,600 m³ / s. 3 / s; The specific scheduling objective for flood protection area 3 is: when encountering a 100-year design flood, the peak flow at flood control station S3 should not exceed 83,100 m³ / s. 3 / s.

[0065] Step 3: Select the typical design flood process of 1989 with flood control station S3 as the typical control station (design frequency is once every 100 years. According to the flood control needs of downstream flood protection area 1, flood protection area 2, and flood protection area 3, the reservoir starts flood control scheduling in the 10th to 17th time period, each time period lasts 6 hours), and carry out flood control scheduling calculations for flood protection area 1, flood protection area 2, and flood protection area 3.

[0066] Based on the Muskingen model, a river flood evolution model was constructed from the reservoir to downstream flood control stations S1, S2, and S3. The model was used to calculate the flood evolution of the river channel at each 1000 m³ impoundment rate. 3 At a rate of / s, the maximum flow reduction at each downstream flood control station is 600m³. 3 / s, 500m 3 / s, 400m 3 / s, with the maximum reduction occurring in periods 1, 4, and 6 (each period lasting 6 hours). Analysis shows that the effective short-term hydrological forecast for each flood control station is more than 3 days, which can effectively support effective reservoirs in carrying out flood control scheduling based on the time of maximum reduction.

[0067] Based on the flood control scheduling methods for different regions and considering the design flood processes of the reservoir and various flood control stations, flood regulation calculations were performed for each flood control station. The target discharge flow for flood control scheduling of the reservoir for flood protection areas 1, 2, and 3 in the 10th time period (the time period when flood control scheduling is initiated) is 17200 m³ / s. 3 / s, 17200m 3 / s, 1400m 3 / s, the maximum allowable discharge flow of the reservoir during this period is approximately 20,000 m³ / s. 3 / s, minimum discharge flow rate is 2500m³ / s. 3 / s. Considering the various scheduling constraints of the reservoir, the calculated outflow during this period is 2500 m³ / s. 3 / s=Min(Max(Min(1400m 3 / s,17200m 3 / s,17200m 3 / s), 2500m 3 / s), 20000m 3 / s).

[0068] Step 4: Based on the reservoir's previous discharge flow process and the determined current discharge flow of 2500 m³ / h. 3 / s, according to the river flood evolution model from the reservoir to each downstream flood control station constructed in step 3, calculate the new forecast flow process of each downstream flood control station after the reservoir impounds the water.

[0069] Step 5: Determine if it is the end of the flood period. It can be seen that the current period 10 is less than the total number of periods 35. Then let the calculation period i = i + 1, repeat steps (3) and (4) to perform flood regulation calculation until i = 35, then the flood regulation calculation of the flood is completed, and finally output the complete discharge flow process of the reservoir during the entire design flood. The process ends.

[0070] To further illustrate the calculation effect of the present invention, this embodiment compares the reservoir outflow and flood control storage capacity usage obtained using different calculation methods. Table 1 shows the reservoir outflow after flood control scheduling calculations for periods 10-17 in this embodiment. The comparison of the outflow process during the entire flood is as follows: Figure 3 As shown.

[0071] It can be seen that by adopting the calculation method described in this invention, the outflow process when the reservoir initiates flood control scheduling for the downstream protection area is given more accurately. Under the premise of meeting the reservoir scheduling regulations, the amount of flood control storage capacity used is reduced, and the flood control benefits per unit storage capacity are maximized.

[0072] All other unspecified parts belong to the prior art.

[0073] Table 1 shows the reservoir outflow process obtained using different flood control scheduling methods.

[0074]

Claims

1. A multi-regional flood control scheduling calculation method coupled with the evolution of floodwaters in the downstream channel of a reservoir, characterized in that: Includes the following steps: (1) Collect basic data on reservoir flood control scheduling and clarify different flood protection areas downstream of the reservoir; (2) Identify the flood control stations, dispatching targets, and dispatching methods corresponding to each flood protection area, among which, the first j Each flood protection area corresponds to a flood control station. S j , j =1, 2, ..., m , m The total number of flood protection areas, m≥2; flood control stations S j The corresponding scheduling objective is to control the flood peak flow at each flood control station by impounding floodwaters through reservoirs, ensuring that it does not exceed the safe discharge capacity of the river channel. QF j ; (3) The first flood of this event i Flood control calculations are performed based on the time period and the flood control stations. S j During the period TF j Latest forecast traffic The reservoir was determined in the [number]th [year]. i The time period is for flood control stations. S j Target discharge flow rate for flood control scheduling QR j,i for: ； in, i =1, 2, ..., N , N This represents the total number of time periods during this flood event. N ≥1; QIN i Let i be the inflow rate of the reservoir during the i-th time period. QC The flood control capacity is determined based on the reservoir's flood control capabilities. QD j To impound water flow from upstream reservoirs QC downstream flood control stations S j Maximum reduction in forecast flow, TF j Maximum reduction QD j Corresponding time period; Then, taking into account the upper limit of flood control storage capacity reserved by the reservoir for each flood protection area. V j Calculate the reservoir's water level at the 1st... i The time period refers to the maximum allowable water storage capacity for flood control scheduling in all flood protection areas. QM j,i Considering other scheduling constraints of the reservoir, determine the first i Outbound flow during the period QR i ; (4) Based on the reservoir's outflow process in the early stage, calculate the downstream river flood evolution and determine the downstream flood control stations after the reservoir's operation. S j New forecast flow process; (5) Determine whether it is the end of the flood period. If not, then set the period as follows: i = i + 1. Repeat steps (3) and (4) to perform flood control calculations; if so, the flood control calculation for the flood is complete.

2. The multi-regional flood control scheduling calculation method for coupled reservoir downstream river flood evolution according to claim 1, characterized in that: In step (1), the basic data includes the reservoir's scheduling procedures, water level and reservoir capacity curves, discharge capacity curves, flood control limit water level, flood control high water level, maximum daily variation of reservoir water level, maximum / minimum discharge flow of the reservoir to meet scheduling needs, upper limit of flood control storage capacity reserved by the reservoir for each flood protection area, propagation time of the reservoir's discharge flow to the downstream flood protection area, flood control scheduling methods of the reservoir for different downstream flood protection areas, and design floods of different frequencies.

3. The multi-regional flood control scheduling calculation method for coupled reservoir downstream river flood evolution according to claim 1, characterized in that: Step (3) includes the following steps: (3.1) In accordance with the reservoir operation regulations and the operation objectives of each flood control station, the first phase of this flood event was determined. i Flood control calculations were performed for different time periods to obtain the target outflow from the reservoir when conducting flood control scheduling for each downstream flood protection area; among them, the first... j When conducting flood control scheduling for each flood protection area, the target outflow of the reservoir is: QR j,i ; (3.2) Combine the upper limit of flood control storage capacity reserved by the reservoir for each flood protection area. V j Calculate the reservoir's water level at the 1st... i The time period refers to the maximum allowable water storage capacity for flood control scheduling in all flood protection areas. QM j,i ; (3.3) When considering other scheduling objectives of the reservoir in the overall scheduling procedure, and determining it as multi-regional flood control scheduling, the reservoir in the first... i Actual outbound flow during the period QR i .

4. The multi-regional flood control scheduling calculation method for coupled downstream river flood evolution of a reservoir as described in claim 3, characterized in that: Step (3.1) includes the following steps: (3.1.1) By constructing reservoirs to various flood control stations S j The river flood evolution model determines the upstream reservoir's interception flow as... QC At that time, after the river floodwaters had subsided and leveled out, the downstream flood control stations... S j Maximum reduction in forecast flow QD j and the period corresponding to the maximum reduction TF j ; QC The level of floodwater retention determined based on the reservoir's flood control capacity; (3.1.2) Analysis yielded the results for each flood control station. S j Hydrological forecast period is TP j The hydrological forecast period for each flood control station is determined to be no less than the flood propagation time from the reservoir to the flood control station. TP j ≥ TF j ; (3.1.3) Obtain information on each flood control station S j During the period TF j Forecast flow Then the reservoir is in the first i The time period is for flood control stations. S j The target discharge flow rate for flood control scheduling is: ;in: QIN i For the reservoir i Inflow to the reservoir during the specified time period; calculate the reservoir's flow rate during the specified time period. i The time period refers to the target discharge flow rate for flood control scheduling at all flood control control stations.

5. The multi-regional flood control scheduling calculation method for coupled reservoir downstream river flood evolution according to claim 4, characterized in that: Step (3.1.1) includes the following steps: (a) Calculations were performed using the Muskingen channel flood evolution model: , Q t , Q t-1 The first t , t-1 Reservoir outflow during specific time periods , The first t , t-1 Flow rates were calculated at downstream flood control stations during the specified time period. C 0 , C 1 , C 2 This represents the river channel evolution coefficient. (b) Subtract the newly added impounded flow from the original outflow from the reservoir. QC The forecast flow sequences for each downstream flood control station were recalculated. (c) Compare the forecast flow processes of downstream flood control stations before and after reservoir impoundment, and clarify the maximum reduction in flow at downstream flood control stations and the time period after reservoir impoundment.

6. The multi-regional flood control scheduling calculation method for coupled reservoir downstream river flood evolution according to claim 3, characterized in that: In step (3.2), the upper limit of flood control storage capacity reserved by the reservoir for each flood protection area is considered. V j Calculate the reservoir in the first i The time period refers to the maximum allowable water storage capacity for flood control operations at each flood control station. QM j,i It is calculated using the following formula: ； when QR x = QR j,x hour, ; when QR x ≠ QR j,x hour, ;in, This represents the length of the time period.

7. The multi-regional flood control scheduling calculation method for coupled reservoir downstream river flood evolution according to claim 3, characterized in that: In step (3.3), the maximum allowable storage capacity obtained in step (3.2) is first considered. QM j,i Recalculate the new target discharge flow rate from the reservoir: Then the reservoir is in the first i Outbound flow during the period ;in: Q min,i In accordance with the dispatching procedures, the reservoir was on the [date / time]. i The minimum allowable discharge flow rate during the specified time period; Q max,i In accordance with the dispatching procedures, the reservoir was on the [date / time]. i The maximum allowable discharge flow during the specified time period.

8. The multi-regional flood control scheduling calculation method for coupled reservoir downstream river flood evolution according to any one of claims 1-7, characterized in that: In step (4), the reservoir's outflow process in the early stage and the reservoir's first... i Outbound flow during the period QR i By calculating the flood evolution in the downstream river channel, the new forecast flow process for each downstream flood control station can be obtained.

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