CN-122023063-A - Flood end water storage method and system based on reservoir area temporary inundation risk control

CN122023063ACN 122023063 ACN122023063 ACN 122023063ACN-122023063-A

Abstract

The invention discloses a flood end water storage method and system based on reservoir area temporary inundation risk control, and relates to the technical field of hydropower dispatching big data acquisition and processing. The method comprises the steps of constructing a sample set of early accumulated rainfall, forecasting a sample set of warehouse-in peak values and a sample set of actual warehouse-in peak values in an effective prediction period, calculating a warehouse-in peak value flow forecasting error, generating a sample set of warehouse-in peak value forecasting errors according to the magnitude group of the early rainfall, analyzing an error distribution rule of warehouse-in peak value flow forecasting in the effective prediction period, determining a forecasting error estimation function, calculating the highest dam front water levels which are corresponding to different frequency dam address design floods and are not increased in a warehouse area, calculating an estimated value of the current forecasting warehouse-in peak value after the largest small error is considered, comparing the estimated value with the corresponding highest dam front water levels which are not increased in the warehouse area, judging the flooding risk and determining a water storage decision. The flood end water storage method can give consideration to various engineering application targets such as flood control, power generation, water supply and the like of the hydropower station, and reasonably optimizes the engineering scheduling mode.

Inventors

LIU JIAN
CHEN MEI
XIE XIAOQIAN
LIANG LIYUAN
LI JIADI
Cai Ruoyi
Mo Jiehuan
XU YINGJUAN
HUANG DEYUN
JING XIANG
ZHENG DONGYAN
ZHANG BO
LI XIANGYANG
WANG HAN
WANG LIUJIE
ZHANG CAN

Assignees

大唐云南发电有限公司
水利部珠江水利委员会珠江水利综合技术中心

Dates

Publication Date: 20260512
Application Date: 20260413

Claims (9)

1. The method for storing water at the tail of flood based on temporary flooding risk control in a reservoir area is characterized by comprising the following steps: step one, constructing a sample set of early-stage accumulated rainfall according to the early-stage rainfall of the reservoir And a sample set of forecast warehouse-in peak values in the early rainfall and corresponding effective prediction period of the reservoir Actual warehouse-in peak value sample set ; Calculating a warehouse-in peak flow forecast error, and grouping according to the early-stage rainfall magnitude to generate a warehouse-in peak forecast error sample set; Analyzing an error distribution rule of the warehouse-in peak flow prediction in the effective prediction period by adopting a site-division regression method according to a warehouse-in peak prediction error sample set, and determining a prediction error estimation function; calculating the highest dam front water level which is not increased and submerged in the reservoir area and corresponds to the designed flood of different frequency dam sites according to the latest actually measured reservoir area topography of the reservoir; And fifthly, calculating an estimated value of the current forecast warehouse-in peak value considering the maximum small error according to a short-term rolling forecast result of the warehouse-in flow at the flood end, comparing the estimated value with the corresponding highest dam front water level which is not increased and submerged in the warehouse area, judging the submerged risk and determining the water storage decision.
2. The method for storing water at the end of flood based on temporary flooding risk control in a reservoir area according to claim 1, wherein the second step is specifically: Calculating the forecasting initial time as follows according to the early rainfall of the reservoir and the forecasting warehouse-in peak value sample set in the corresponding effective forecasting period Corresponding prediction errors of warehouse-in peak flow in each prediction period ; For earlier accumulated rainfall sample set The samples in the model are grouped according to different level intervals to generate prediction error sample sets corresponding to different rainfall intervals ; Forecasting the peak flow rate of warehouse entry in each forecast period Filling the data into a warehouse-in prediction error sample set according to groups of intervals of different quantity levels Obtaining a warehouse-in forecast error sample set 。
3. The method for storing water at the end of flood based on temporary flooding risk control in a reservoir area according to claim 2, wherein the forecast start time is Corresponding prediction errors of warehouse-in peak flow in each prediction period The calculation formula of (2) is as follows: ; Wherein, the For a forecast in-store peak traffic for a valid forecast period starting at a forecast start time, The peak flow is actually put into storage in the effective prediction period from the prediction starting time.
4. A method for storing water at the end of flood based on temporary flooding risk control in a reservoir area according to claim 2 or 3, wherein the third step is specifically: reservoir-warehouse-in peak-forecast-error-based sample set Analyzing an error distribution rule of the warehouse-in peak flow prediction of the water warehouse in the effective prediction period by adopting a quantile regression method; peak forecast error sample set in reservoir Selecting a plurality of quantile points, and determining prediction error estimation values under different confidence degrees when the corresponding early accumulated rainfall is the same as the prediction period length; Determining a prediction error estimation function corresponding to the dividing point according to the prediction error estimation values under different confidence levels; And calculating parameters of a prediction error estimation function through the fractional loss function and the optimization objective function, and determining the error estimation function.
5. The method for storing water at the end of flood based on temporary flooding risk control in a reservoir area according to claim 4, wherein the forecast error estimation function is as follows: ; ; ; Wherein, the In order to divide the position of the object into the points, And To predict quantile related parameters of the error estimation function, As a residual error, the residual error is determined, Is quantile of The corresponding loss value is used to determine, To indicate a function.
6. The method for storing water at the end of flood based on temporary flooding risk control in a reservoir area according to claim 5, wherein the fourth step is specifically as follows: According to the latest actually measured reservoir area topography of the reservoir, a one-dimensional constant non-uniform flow equation is adopted to establish a reservoir area water surface line calculation model, and reservoir area submerged ranges and reservoir area water surface lines corresponding to different dam front water levels under the flood condition of each dam site design are calculated; according to the reservoir submerged range and reservoir water surface line, calculating the highest dam front water level which is corresponding to different frequency dam site design floods and does not increase reservoir submerged 。
7. The method for storing water at the end of flood based on temporary flooding risk control in a reservoir area according to claim 6, wherein the one-dimensional constant non-uniform flow equation is: ; Wherein, the Is the first The sections correspond to the water depths; is the first The sections correspond to the flow velocity; is the first And from the first to the second The sections correspond to the head loss along the journey; is the first And from the first to the second And local head loss caused by expansion or contraction of the cross section in the process of each cross section.
8. The method for storing water at the end of flood based on temporary flooding risk control in a reservoir area according to claim 7, wherein the fifth step is specifically as follows: according to the warehouse-in flow of flood season the short-term rolling forecast is used, rainfall in the current period When reaching the corresponding interval, the warehouse-in peak value is forecasted according to the forecast information And corresponding peak period Calculating the estimated value of the current forecast warehouse-in peak value considering the maximum small error according to the forecast error estimation function ; Based on the estimated value The reservoir submerged range and reservoir water surface line corresponding to the same-level flow are called to obtain and estimate Corresponding highest dam front water level without increasing reservoir area inundation ; Judging the current actual running dam front water level of the reservoir Whether or not to establish; If the current water storage level of the reservoir meets the flood control safety requirement of the reservoir area, the excess water can be further stored back to be not more than the excess water according to the engineering practical application plan 。
9. A flood end water storage system based on reservoir temporary flooding risk control, comprising a memory and a processor, wherein the memory comprises a flood end water storage method program based on reservoir temporary flooding risk control, and the flood end water storage method program based on reservoir temporary flooding risk control realizes the steps of a flood end water storage method based on reservoir temporary flooding risk control according to any one of claims 1 to 8 when being executed by the processor.

Description

Flood end water storage method and system based on reservoir area temporary inundation risk control Technical Field The invention relates to the technical field of hydropower dispatching big data acquisition and processing, in particular to a flood end water storage method and system based on reservoir area temporary inundation risk control. Background With the large-scale development and comprehensive utilization of hydropower energy in China, hydropower station scheduling in flood season has become a key link for balancing flood control safety and power generation benefits. However, in actual dispatching operation, the reservoirs of the medium and small hydropower stations are forced to maintain low water level operation in the flood season due to factors such as small adjustment reservoir capacity, short flood dispatching decision time and the like, so that engineering benefits cannot be fully exerted. In order to reduce the risk of temporary flooding of a reservoir water return section caused by sudden heavy rainfall in a reservoir area during high water level operation of a flood season, the water level is consistent with a dead water level during the flood season, the output of a unit is seriously blocked, and a power generation water head is lower than a rated value for a long time, so that the power grid dispatching is influenced, and the unit is also caused to operate in an unstable state deviating from an optimal efficiency area. The activation of flood control reservoirs above normal water levels presents serious temporary flooding challenges. Some large and medium-sized reservoirs are difficult to effectively use due to the fact that temporary risk avoiding and transferring mechanisms are immature, flood avoiding facilities are not perfect in construction, compensation mechanisms are not complete, and the like. The dilemma of 'having a warehouse and being difficult to use' is that the reservoir has great discounts on the defending ability before extreme weather events, and meanwhile, under the large meteorological background that the current extreme weather events frequently occur and the flood and the dry conversion of the watershed is less smooth, the comprehensive benefit of the hydropower station is not beneficial to overall exertion. The medium-short term hydrological weather forecast is a decision basis for hydropower station flood season scheduling, but has significant uncertainty. The middle-term hydrologic forecast mainly depends on rainfall prediction results of numerical weather forecast, and a numerical weather forecast model has larger errors for predicting rainfall trend in 3-7 days, and particularly the prediction accuracy of rainfall magnitude and falling area is obviously reduced along with the prolongation of forecast time. This uncertainty significantly increases the difficulty of the reservoir scheduling decisions-too conservative pre-venting may waste valuable water resources, while insufficient pre-venting may exacerbate the subsequent flood pressures. Rainfall forecast is affected by a plurality of factors including rainfall magnitude, drop zone, warehouse-in flow level and the like, so that forecast errors are unavoidable. Although rainfall adjacent forecasting systems (such as 'small vortex' systems) can predict the position and intensity of a rainy region for 1-2 hours in the future, the rainfall adjacent forecasting systems still face a plurality of challenges that complex terrains can cause local rainfall enhancement and are difficult to capture accurately by conventional observation networks, reliability of a forecasting method based on statistics is limited due to burstiness and randomness of rainfall processes, and runoff forecasting errors are further amplified by uncertainty of hydrologic model parameters. These uncertainties put the forecast-based hydropower station scheduling decisions at risk, possibly leading to temporary flooding of the reservoir or waste of water resources. The temporary flooding risk and the short-term prediction uncertainty risk of the reservoir area are mutually interwoven to form a complex management challenge, and the development of joint analysis and cooperative regulation is needed. The current flood season hydropower station dispatching mode focuses on single risk management and control, or prediction uncertainty is mainly used for dynamic control of reservoir flood season running water level, or short-term prediction error features are applied to quantitative management of prediction dispatching risks. However, in the context of climate change, extreme rainfall events tend to increase in frequency, making the interaction of the risk of temporary flooding in the reservoir area with the risk of short-term forecast uncertainty more complex. Disclosure of Invention In view of the above problems, the invention aims to provide a flood end water storage method and system based on temporary flooding risk control in a reservoir area. And (3