Method for determining combined drought-resisting multi-dimensional early warning parameters of cascade reservoir group

Abstract

The invention belongs to the technical field of hydraulic engineering, and discloses a cascade reservoir group combined drought resistance multi-dimensional early warning parameter determination method, which comprises the following steps: constructing a plurality of drought scenes and a cascade reservoir group-based conventional scheduling model and a drought resistance scheduling model according to a drainage basin to which a cascade reservoir group belongs; inputting each drought scene into a drought-resistant scheduling model, and determining a supply-limited early-warning water level of each reservoir in each drought scene according to a solving result of the drought-resistant scheduling model; and inputting each drought scene into the conventional scheduling model, and determining a drought-resistant early warning period and a limited water supply coefficient of each reservoir in each drought scene according to a scheduling comparison result of the cascade reservoir group under the two scheduling models. According to the method, the supply limit early-warning water level of the cascade reservoir group in the drainage basin is calculated, the drought-resistant early-warning period and the water supply limit coefficient are determined, and the drought early-warning system is constructed, so that the drought trend is pre-judged in advance, man-made drought inducing and water supply limit measures are implemented, the reservoir water amount is effectively stored, and the impact of drought on water resource supply and demand balance is reduced.

Description

Technical Field

[0001] The invention discloses a method for determining multi-dimensional early warning parameters of a cascade reservoir group combined with drought resistance, and belongs to the technical field of water conservancy engineering. Background Art

[0002] As one of the most common and serious natural disasters in the world, drought disasters are of great importance. They not only damage the natural environment and affect agricultural production, but also pose a major threat to the sustainable development of the social economy. According to statistics, the economic losses caused by drought in the world each year are as high as 6-8 billion US dollars, far exceeding other meteorological disasters.

[0003] As a key engineering measure for drought relief in the river basin, reservoirs play an irreplaceable role in alleviating drought and ensuring water supply through their storage capacity. With the help of reservoirs' storage function, the natural runoff process of the main and tributary rivers in the river basin can be scientifically adjusted to match the water demand process of production, life and ecology in different regions, thereby effectively alleviating the losses caused by drought.

[0004] However, the current construction of reservoir drought warning system has obvious deficiencies. Especially in the joint drought prevention of cascade reservoirs, there is a lack of systematic methods that take into account both water supply and demand from the perspective of the whole basin. The existing warning system focuses on the monitoring and prediction of a single reservoir or a local area, ignoring the synergy between multiple reservoirs in the basin and the hydrological connection between upstream and downstream, resulting in inefficient water resource allocation and difficulty in achieving optimal allocation and efficient utilization.

[0005] In addition, the traditional early warning model is unable to fully reflect the complex hydrological processes in the basin and the mutual influence between reservoirs, making the early warning information lack accuracy and timeliness. Summary of the invention

[0006] The purpose of the present invention is to provide a method for determining multi-dimensional early warning parameters for joint drought resistance of a cascade reservoir group, aiming to solve the limitations of current technologies. Traditional early warning models mainly focus on the monitoring and prediction of a single reservoir or a local area, often ignoring the synergistic effect between multiple reservoirs in the entire basin, as well as the close hydrological connection between upstream and downstream, making it difficult to achieve the optimal allocation and efficient utilization of water resources. In order to overcome these technical difficulties, the present invention proposes a method for determining multi-dimensional early warning parameters for joint drought resistance of a cascade reservoir group, and the specific scheme is as follows: A method for determining multi-dimensional early warning parameters for joint drought relief of cascade reservoirs, comprising: Step 1: construct multiple drought scenarios and conventional scheduling models and drought-resistant scheduling models based on the cascade reservoir groups according to the river basins to which the cascade reservoir groups belong; Step 2: input each drought scenario into the drought-resistant scheduling model, and determine the supply limit warning water level of each reservoir under each drought scenario according to the solution result of the drought-resistant scheduling model; Step 3: Input each drought scenario into the conventional scheduling model, and determine the drought warning period and restricted water supply coefficient of each reservoir in each drought scenario according to the scheduling comparison results of the cascade reservoir group under the two scheduling models.

[0007] Preferably, multiple drought scenarios are constructed, specifically including: Multiple drought scenarios are constructed based on the hydrological data of the basin to which the cascade reservoirs belong and the preset drought tolerance corresponding to different scenarios in the basin.

[0008] Preferably, multiple drought scenarios are constructed based on the hydrological data of the basin to which the cascade reservoir group belongs and the preset drought tolerance corresponding to different scenarios in the basin, specifically including: Selecting multiple typical years corresponding to different drought levels based on historical hydrological data of the watershed to which the cascade reservoir group belongs; A plurality of drought scenarios are constructed according to the hydrological processes of the plurality of typical years and the preset drought tolerances corresponding to different scenarios in the basin.

[0009] Preferably, multiple typical years corresponding to different drought levels are selected according to the historical hydrological data, specifically including: A plurality of typical years of different drought levels are selected according to the water demand processes corresponding to different scenarios and the water inflow difference of the cascade reservoir group.

[0010] Preferably, the optimization objective of the drought resistance scheduling model is: The sum of the water supply satisfaction deviation values ​​in different scenarios within the basin is the smallest.

[0011] Preferably, the constraints of the drought resistance scheduling model are: Reservoir water level constraints, reservoir group water balance constraints, reservoir discharge flow constraints, warning water shortage rate threshold constraints and non-negative constraints.

[0012] Preferably, the warning water shortage rate threshold is determined according to the warning level under the drought level corresponding to the drought scenario.

[0013] Preferably, the step 3 specifically includes: Input each drought scenario into the conventional scheduling model to determine the scheduling comparison results of the cascade reservoir group under the conventional scheduling model and the drought-resistant scheduling model under each drought scenario; The drought warning period and the restricted water supply coefficient of each reservoir under each drought scenario are determined according to the dispatch comparison results.

[0014] Preferably, determining the drought warning period of each reservoir under each drought scenario according to the dispatch comparison result specifically includes: The period in the scheduling comparison result when the outflow of each reservoir in the drought-resistant scheduling model is less than the corresponding period in the conventional scheduling model is recorded as the drought-resistant warning period of the reservoir under the corresponding drought scenario.

[0015] Preferably, determining the restricted water supply coefficient of each reservoir in each drought scenario according to the scheduling comparison result specifically includes: During the drought warning period, the proportion of simulated water supply from each reservoir to each water user under the corresponding drought scenario in the drought scheduling model is recorded as the restricted water supply coefficient of the reservoir under the corresponding drought scenario.

[0016] Beneficial effects: The method for determining the multi-dimensional warning parameters of the present invention establishes a drought-resistant dispatching model for the cascade reservoir group in the river basin to obtain an optimized reservoir dispatching method, guides the reservoir to release stored water resources flexibly and efficiently, and converts the "concentrated damage" that may have been caused into "wide and shallow damage", thereby reducing the impact of drought on the balance of water supply and demand, protecting the stable operation of regional social and economic activities and the sustainability of the ecological environment; by predicting the drought trend, implementing artificial drought and water supply restriction measures, and effectively storing reservoir water. The present invention uses the reservoir's limited supply warning water level, drought warning period and water supply restriction coefficient as parameters of the multi-dimensional warning mechanism. In the drought warning mode, decision makers use the method for determining the warning parameters to issue early warnings and take effective measures to reduce losses due to drought, so that the overall water supply situation of water-demanding departments is better. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is the water demand process in a typical year of mild drought and moderate drought in the embodiment of the present invention, wherein (a) is the water demand process in a typical year of mild drought, and (b) is the water demand process in a typical year of moderate drought; Figure 2 is the water demand process in a typical year of severe drought and extreme drought in the embodiment of the present invention, wherein (c) is the water demand process in a typical year of severe drought, and (d) is the water demand process in a typical year of extreme drought; Figure 3 is the supply limit warning water level of the Longyangxia Reservoir in the embodiment of the present invention; Figure 4 is the limited supply warning water level of the Liujiaxia Reservoir in the embodiment of the present invention; Figure 5 is the limited supply warning water level of the Xiaolangdi Reservoir in an embodiment of the present invention; Figure 6 This is the dispatching process of the Longyangxia Reservoir under two models in an embodiment of the present invention; Figure 7 This is the dispatching process of the Liujiaxia Reservoir under two models in an embodiment of the present invention; Figure 8 This is the dispatching process of the Xiaolangdi Reservoir under two models in an embodiment of the present invention; Fig. 9 is the limited water supply coefficient corresponding to different drought scenarios in the embodiment of the present invention; Fig.10 It is a flow chart of a method for determining multi-dimensional early warning parameters for joint drought resistance of a cascade reservoir group according to the present invention. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the present invention more clear, the present invention is further described in detail below in conjunction with specific implementation methods. It should be understood that the specific implementation methods described here are only used to explain the present invention and do not limit the scope of protection of the present invention.

[0019] The present invention proposes Fig.10 The method for determining multi-dimensional early warning parameters for joint drought resistance of a cascade reservoir group is shown, which aims to improve the drought resistance capacity in the basin through scientific and reasonable prediction and scheduling. Specifically, this embodiment will take the Yellow River Basin as an example to describe the specific implementation of the present invention in detail: Step 1: construct multiple drought scenarios based on the hydrological data of the basin to which the cascade reservoir group belongs, and construct a conventional dispatching model and a drought-resistant dispatching model for the cascade reservoir group; Furthermore, constructing multiple drought scenarios specifically includes: constructing multiple drought scenarios based on the hydrological data of the basin to which the cascade reservoir group belongs and the preset drought tolerance corresponding to different scenarios in the basin. The preset drought tolerance corresponding to different scenarios represents the preset drought tolerance of each water user in the basin.

[0020] Furthermore, multiple drought scenarios are constructed based on the hydrological data of the basin to which the cascade reservoir group belongs and the preset drought tolerance of each water user in the basin, specifically including: obtaining historical hydrological data of the basin to which the cascade reservoir group belongs, and selecting multiple typical years corresponding to different drought levels based on the historical hydrological data; and constructing multiple drought scenarios based on the hydrological processes of the multiple typical years and the preset drought tolerance of each water user in the basin.

[0021] In this embodiment, it specifically includes consulting the hydrological yearbook and other information of the Yellow River Basin, and collecting the long series of water inflow and water demand of the main and tributary rivers in the basin. Specifically, it includes Longyangxia Reservoir, Liujiaxia Reservoir and Xiaolangdi Reservoir, as well as Taohe River, Huangshui River, Datong River, Fenhe River, Weihe River, Qinhe River, Yiluo River and Dawen River connected to the main stream of the Yellow River. Taking the hydrological year as the statistical period, the water shortage rate of each hydrological year is calculated according to the water demand of the water-using unit. The calculation formula of the water shortage rate is as follows:

[0022] Where: for Water shortage rate in the hydrological year; and They are Water demand and water inflow in the hydrological year.

[0023] Further, the drought level of a typical year is determined according to the water shortage rate of the typical year.

[0024] After obtaining the water shortage rate of each hydrological year, the drought level of each hydrological year is determined according to the drought level classification standard shown in Table 1. Finally, multiple typical years of different drought levels are selected according to the difference between the water demand process corresponding to different scenarios and the water inflow of the cascade reservoir group. That is, according to the most unfavorable principle of the water demand process of the water user (that is, the water demand process of each water user is the most different from the water inflow of the cascade reservoir group), a typical year is selected in each warning level under each drought level. In this embodiment, the water inflow and water demand process of the typical years of different drought levels are as follows: Figure 1 and Figure 2 shown.

[0025] Table 1 Drought levels at different water shortage rates

[0026] Subsequently, considering the water demand characteristics of water-using units in the Yellow River Basin and their ability to withstand water shortages, the drought tolerance of each water-using unit was preset, and different drought scenarios were constructed based on the drought tolerance of each water-using unit and various typical year combinations.

[0027] Constructing a conventional scheduling model and a drought-resistant scheduling model, specifically including: collecting data on the cascade reservoir groups in the Yellow River Basin, as well as the needs of water users in different time periods, and constructing a conventional scheduling model and a drought-resistant scheduling model.

[0028] The construction of the conventional scheduling model is as follows: Considering the water supply of the main and tributary rivers in the Yellow River Basin, the water demand of each reservoir is calculated. The calculation formula is as follows:

[0029] Where: is the simulation period; for Reservoir The amount of water stored during the period; for The amount of water inflow from the main stream during the period; for The tributaries within the controlled catchment area of ​​the reservoir are The amount of water inflow during the period.

[0030] A conventional scheduling model is established based on standardized operating rules and various constraints. The conventional scheduling model is used to simulate the operation of cascade reservoirs. The conventional scheduling model calculates the relationship between the water storage and water demand of each reservoir in the Yellow River Basin during the simulation period in each drought scenario; it simulates the operation process of each reservoir in the Yellow River Basin. If the reservoir water storage is greater than the water demand, water will be supplied on demand; if the reservoir water storage is less than the water demand, the reservoir will use all the water above the dead water level for water supply; if the reservoir water storage is greater than the maximum water storage capacity of the reservoir, the reservoir will increase the discharge to keep the water storage at the maximum position.

[0031] The constraints of the conventional scheduling model include: (1) Water balance constraint, as shown in the following formula:

[0032] Where: It is Year The storage capacity of the reservoir at the end of the time period; It is years The inflow to the reservoir during the period; It is Year Downflow during the period.

[0033] (2) Reservoir water level constraint, as shown in the following formula:

[0034] Where: It is the dead water level of the reservoir; It is Year The water level of the reservoir at the end of the period; In the non-flood season, it indicates the normal water storage level of the reservoir, and in the flood season, it indicates the flood limit water level.

[0035] (3) Downstream flow constraint, as shown in the following formula:

[0036] Where: yes Minimum downstream flow requirement within the time period; It is years The outflow from the reservoir at the end of the period; yes The maximum downstream flow demand during the period.

[0037] (4) Non-negative constraints: all variables are non-negative values.

[0038] The construction of drought resistance scheduling model specifically includes: Taking the water level of each reservoir in the cascade reservoir group in the Yellow River Basin and the water level of supply limit warning as decision variables, and taking the minimum sum of the water supply satisfaction deviation values ​​of each water user in the Yellow River Basin (minimum annual fluctuation) as the optimization goal, a drought-resistant scheduling model was constructed according to the optimization goals and constraints.

[0039] The optimization objective of the drought resistance scheduling model is:

[0040] Where: The goal for model optimization; For the Period Water supply satisfaction in each area; for Average water supply satisfaction of the region; It is the average value of the annual water supply satisfaction deviation; is the total number of simulation periods; is the total number of regions.

[0041] The constraints of the drought-resistant scheduling model include reservoir water level constraints, reservoir group water balance constraints, reservoir discharge flow constraints, warning water shortage rate threshold constraints and non-negative constraints, as follows: (1) Water balance constraint, as shown in the following formula:

[0042] Where: It is Year The storage capacity of the reservoir at the end of the time period; It is years The inflow to the reservoir during the period; It is Year Downflow during the period.

[0043] (2) Reservoir water level constraint, as shown in the following formula:

[0044] Where: It is the dead water level of the reservoir; It is Year The water level of the reservoir at the end of the period; In the non-flood season, it indicates the normal water storage level of the reservoir, and in the flood season, it indicates the flood limit water level.

[0045] (3) Downstream flow constraint, as shown in the following formula:

[0046] Where: yes Minimum downstream flow requirement within the time period; It is years The outflow from the reservoir at the end of the period; yes The maximum downstream flow demand during the period.

[0047] (4) The early warning water shortage rate threshold constraint is as follows:

[0048] Where: For the Drought level Water shortage rate in the basin under the level 1 warning level; For the basin Water shortage rate in the basin under the level 1 warning.

[0049] (5) Non-negative constraints: all variables are non-negative.

[0050] The above-mentioned warning water shortage rate threshold is determined according to the warning level under the drought level corresponding to the drought scenario. The warning levels specifically include level I, level II, level III, and level IV. The warning water shortage rate threshold represents the achievement threshold corresponding to the simulated scheduling of the drought resistance scheduling model under each warning level.

[0051] Step 2: input each drought scenario into the drought relief scheduling model, and determine the supply limit warning water level of each reservoir under the drought scenario according to the solution result of the drought relief scheduling model; Specifically, a drought scenario is input into the conventional operation model to simulate the operation process of the cascade reservoirs in the Yellow River Basin, and the drought scenario is input into the drought resistance operation model to simulate the drought resistance operation process of the cascade reservoirs in the Yellow River Basin; The conventional dispatching model and drought-resistant dispatching model are compiled and solved by using the Gurobi solver package in Python, and the conventional dispatching process and drought-resistant dispatching process of the cascade reservoirs of the input drought scenario are simulated. Among them, the water level of the reservoir obtained in the drought-resistant dispatching process is recorded as the limited supply warning water level corresponding to the warning level under the drought level corresponding to the drought scenario. The limited supply warning water level is an indicative indicator to support the release of drought warning signals in the basin. In the early stage of reservoir dispatch, the limited supply water level is used for early warning, and artificial supply is limited to increase the water supply in the later stage of drought. The higher the drought level, the more water needs to be stored in advance. Therefore, the limited supply warning water level should change with the different drought levels. At the same time, under the same level of drought, the limited supply warning water level for different degrees of drought scenarios should also be different. That is, different limited supply warning water levels correspond to different warning levels, and different drought-resistant measures are taken.

[0052] In this embodiment, the limited supply warning water levels corresponding to different warning levels of Longyangxia, Liujiaxia and Xiaolangdi reservoirs in the Yellow River Basin under different drought levels are as follows: Figure 3-Figure 5 shown.

[0053] Step 3: Input each drought scenario into the conventional scheduling model, and determine the drought warning period and restricted water supply coefficient of each reservoir under each drought scenario according to the scheduling comparison results of the cascade reservoir group under the two scheduling models.

[0054] Furthermore, the step 3 specifically includes: Each drought scenario is input into the conventional scheduling model to determine the scheduling comparison results of the cascade reservoir group under the conventional scheduling model and the drought-resistant scheduling model under each drought scenario; the drought warning period and the restricted water supply coefficient of each reservoir under each drought scenario are determined according to the scheduling comparison results. Specifically, the period in the scheduling comparison results when the outflow of each reservoir in the drought-resistant scheduling model is less than the corresponding period of the conventional scheduling model is recorded as the drought warning period of the reservoir under the corresponding drought scenario. Further, during the drought warning period, the proportion of simulated water supply of each reservoir to each water user under the corresponding drought scenario in the drought-resistant scheduling model is recorded as the restricted water supply coefficient of the reservoir under the corresponding drought scenario. The drought warning period is the "flexibility" to provide preparation time for coordinating the amount of water required for drought relief in the later stage of drought. The longer the warning period, the more drought relief water can be stored in advance for the later stage of drought, and the easier it is to achieve wide and shallow damage during the entire scheduling period; the shorter the warning period, if the forecast deviation of the drought event is large, it is easy to aggravate the irreversible drought losses in the early stage of drought. The water supply restriction coefficient is a drought relief measure corresponding to the water supply restriction level. By artificially restricting the water supply during the warning period, the water supply available in the later period can be increased. Different water supply restriction coefficients correspond to different water supply restriction warning water levels.

[0055] The water level for water restriction warning affects the drought warning period and the water restriction ratio during the warning period. The longer the warning period, the smaller the water restriction coefficient; the shorter the warning period, the larger the water restriction coefficient.

[0056] Specifically, the dispatching process and drought relief dispatching process of the same drought scenario are compared, and the conventional dispatching process and drought relief dispatching process of the reservoirs in the two dispatching models are compared. If the outflow of the reservoir in the drought relief dispatching process is less than that in the conventional dispatching process, then this period is the drought relief warning period. Specifically, in this embodiment, the conventional dispatching process and drought relief dispatching process of Longyangxia, Liujiaxia and Xiaolangdi reservoirs in the same drought scenario are plotted in the same figure. The plots of each reservoir under different drought levels are as follows: Figure 6-Figure 8 shown.

[0057] The simulated water supply rate of different water users in the drought warning period during the drought dispatch process is recorded as the restricted water supply coefficient. Specifically, in this embodiment, the restricted water supply coefficient of the basin under different drought levels is as follows: Fig. 9 The restricted water supply coefficients of the tributaries of the Yellow River in this embodiment are shown in Table 2.

[0058] Table 2 Restricted water supply coefficients of each tributary

[0059] The present invention calculates the supply limit warning water level of the cascade reservoir group in the basin, determines the drought warning period and the water supply restriction coefficient, and constructs a drought warning system to predict the drought trend in advance, implement artificial drought and water supply restriction measures, and effectively store the water volume of the reservoir. When a drought occurs, the reservoir guided by the model can release the stored water resources more flexibly and efficiently, and transform the "concentrated damage" that may have been caused into "wide and shallow damage", thereby reducing the impact of drought on the balance of water supply and demand, and protecting the stable operation of regional social and economic activities and the sustainability of the ecological environment. Reservoir decision makers can reduce losses due to drought through early warning and take effective measures, so that the overall water supply situation of water-demanding departments is better.

[0060] The above are only several embodiments of the present invention and are not intended to limit the present invention in any form. Although the present invention is disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any technician familiar with the profession, without departing from the scope of the technical solution of the present invention, using the above disclosed technical content to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A method for determining multi-dimensional early warning parameters for joint drought relief of cascade reservoirs, characterized in that: include: Step 1: construct multiple drought scenarios and conventional scheduling models and drought-resistant scheduling models based on the cascade reservoir groups according to the river basins to which the cascade reservoir groups belong; Step 2: input each drought scenario into the drought-resistant scheduling model, and determine the supply limit warning water level of each reservoir under each drought scenario according to the solution result of the drought-resistant scheduling model; Step 3: Input each drought scenario into the conventional scheduling model, and determine the drought warning period and restricted water supply coefficient of each reservoir in each drought scenario according to the scheduling comparison results of the cascade reservoir group under the two scheduling models.

2. The method for determining multi-dimensional early warning parameters for joint drought relief of cascade reservoirs according to claim 1 is characterized in that: Build multiple drought scenarios, including: Multiple drought scenarios are constructed based on the hydrological data of the basin to which the cascade reservoirs belong and the preset drought tolerance corresponding to different scenarios in the basin.

3. The method for determining multi-dimensional early warning parameters for joint drought relief of cascade reservoirs according to claim 2 is characterized in that: Based on the hydrological data of the basin to which the cascade reservoirs belong and the preset drought tolerance corresponding to different scenarios in the basin, multiple drought scenarios are constructed, including: Selecting multiple typical years corresponding to different drought levels based on historical hydrological data of the watershed to which the cascade reservoir group belongs; A plurality of drought scenarios are constructed according to the hydrological processes of the plurality of typical years and the preset drought tolerances corresponding to different scenarios in the basin.

4. The method for determining multi-dimensional early warning parameters for joint drought relief of cascade reservoirs according to claim 3 is characterized in that: According to the historical hydrological data, multiple typical years corresponding to different drought levels are selected, including: A plurality of typical years of different drought levels are selected according to the water demand processes corresponding to different scenarios and the water inflow difference of the cascade reservoir group.

5. The method for determining multi-dimensional early warning parameters for joint drought relief of cascade reservoirs according to claim 1, characterized in that: The optimization goal of the drought resistance scheduling model is: The sum of the water supply satisfaction deviation values ​​in different scenarios within the basin is the smallest.

6. The method for determining multi-dimensional early warning parameters for joint drought relief of cascade reservoirs according to claim 1, characterized in that: The constraints of the drought resistance scheduling model are: Reservoir water level constraints, reservoir group water balance constraints, reservoir discharge flow constraints, warning water shortage rate threshold constraints and non-negative constraints.

7. The method for determining multi-dimensional early warning parameters for joint drought relief of cascade reservoirs according to claim 6, characterized in that: The warning water shortage rate threshold is determined according to the warning level under the drought level corresponding to the drought scenario.

8. The method for determining multi-dimensional early warning parameters for joint drought relief of cascade reservoirs according to claim 1, characterized in that: The step 3 specifically includes: Input each drought scenario into the conventional scheduling model to determine the scheduling comparison results of the cascade reservoir group under the conventional scheduling model and the drought-resistant scheduling model under each drought scenario; The drought warning period and the restricted water supply coefficient of each reservoir under each drought scenario are determined according to the dispatch comparison results.

9. The method for determining multi-dimensional early warning parameters for joint drought relief of cascade reservoirs according to claim 8, characterized in that: The drought warning period of each reservoir under each drought scenario is determined according to the dispatch comparison results, specifically including: The period in the scheduling comparison result when the outflow of each reservoir in the drought-resistant scheduling model is less than the corresponding period in the conventional scheduling model is recorded as the drought-resistant warning period of the reservoir under the corresponding drought scenario.

10. The method for determining multi-dimensional early warning parameters for joint drought relief of cascade reservoirs according to claim 9, characterized in that: According to the scheduling comparison results, the restricted water supply coefficient of each reservoir under each drought scenario is determined, specifically including: During the drought warning period, the proportion of simulated water supply from each reservoir to each water user under the corresponding drought scenario in the drought scheduling model is recorded as the restricted water supply coefficient of the reservoir under the corresponding drought scenario.

Images