Methods and apparatus for predicting the attenuation variation of daily regulating waves along the path of a hydropower station

Abstract

This invention provides a method and apparatus for predicting the attenuation of daily regulating waves along the course of a hydropower station. The method includes selecting N cross-sectional locations within the potential influence range of the daily regulating wave on a target river section and dividing the river section into N-1 sub-segments. Simultaneously, topographic data for each cross-section is acquired, and daily average water level-daily average flow relationship curves are plotted for each cross-section within the target river section. Hydraulic parameters for each sub-segment are obtained under different characteristic flow rates. Based on the hydraulic parameters of each cross-section under different characteristic flow rates, the attenuation distance of the daily regulating wave under different scheduling conditions is obtained. The impact amplitude and timing of the daily regulating wave at a specific location under different scheduling conditions are also determined. Based on the characteristic that the amplitude of the daily regulating wave is relatively small compared to the river channel depth, this invention proposes a simplified process for solving the one-dimensional flow motion equation of an open channel, thereby enabling quantitative prediction of the impact of the daily regulating wave on downstream navigation channels. Its advantages include low data requirements and computational complexity, ease of application, high reliability, and ease of promotion.

Description

Technical Field

[0001] This invention belongs to the field of water conservancy and waterway engineering technology, specifically relating to a method and apparatus for predicting the daily attenuation changes of regulating waves along the path of a hydropower station. Background Technology

[0002] In recent years, the proportion of hydropower in my country's power development plans has been increasing year by year, and the construction of hydropower stations has become more and more common. Hydropower stations undertake peak-shaving tasks in the power system, and the peak load flow generated and discharged cyclically will have a periodic impact on the water level in downstream river channels, resulting in daily regulating waves. The characteristics of daily regulating waves are frequent intraday water level changes, and during propagation, the wave height gradually decreases due to the natural regulation of the river channel until it disappears after a certain distance downstream of the reservoir. In addition to the natural water surface gradient, the daily regulating wave also has an additional water surface gradient during its propagation, causing periodic changes in water level, flow velocity, water depth, and gradient, which adversely affects the normal operation of ports and navigation facilities and the safe navigation of ships in a certain section downstream of the dam. Shipping departments need to rationally arrange and select different times of day for navigation based on the propagation pattern of the daily regulating wave of the power station, in conjunction with the ship's range and draft. Since the daily regulation of hydropower stations often plays a dominant role in the conflict between hydropower station operation and downstream shipping, coordinating the conflict between hydropower and shipping by predicting the attenuation changes of the daily regulation wave along the route is an important prerequisite for achieving coordinated development between hydropower and shipping.

[0003] In current engineering practice, the common methods for predicting the attenuation of daily regulating waves along the river's course in power plants include physical models, numerical simulations, or a combination of both. Physical models scale the actual topography of the engineering river section to a specific scale, and then simulate the flow process under different scheduling schemes at the model inlet to study the hydrodynamic characteristics and navigation factors along the river's course. Numerical simulation methods, on the other hand, use software to build mathematical models of the engineering river section, allowing for multiple, large-scale simulations of the flow field. While these methods can accurately determine the propagation patterns of daily regulating wave attenuation along the river's course, they rely on detailed river topographic data and expensive experimental and computational equipment, resulting in high modeling costs, long development cycles, and high levels of expertise required from the technical personnel implementing the methods, thus presenting numerous limitations in engineering practice.

[0004] From an engineering practice perspective, predicting the propagation characteristics of daily regulating waves in power plants primarily faces two types of needs. First, in the impact assessment of daily regulating schemes, it is necessary to rapidly extrapolate the propagation distance of daily regulating waves under various possible operating conditions, enabling the selection of appropriate scheduling options from a large pool of options. Second, in downstream navigation scheduling and navigation aid design, it is necessary to estimate the water level fluctuations, velocity fluctuations, and additional gradients caused by daily regulating waves at various locations, thus providing a basis for safety assessments of waterways and anchorages. To meet these engineering practice needs, it is urgent to propose a method that requires less data, is fast and simple, and can simultaneously calculate the amplitude, phase, and additional gradient of daily regulating waves, in addition to conventional mathematical or physical modeling methods. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a method and apparatus for predicting the attenuation of daily regulating waves along the course of a hydropower station. Based on the characteristic that the amplitude of daily regulating waves is relatively small compared to the depth of the river channel, a simplified process for solving the one-dimensional flow motion equation of an open channel is proposed, thereby enabling quantitative prediction of the impact of daily regulating waves on downstream waterways. Its advantages include low data requirements and computational workload, ease of application, high reliability, and ease of promotion.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0007] A method for predicting the daily attenuation variation of regulating waves along the path of a hydropower station includes the following steps:

[0008] For the target river section, N cross-section locations are selected within the potential influence range of the daily regulating wave of the hydropower station, and the river section is divided into N-1 sub-segments. At the same time, the topographic data of each cross-section is obtained.

[0009] Plot the daily average water level to daily average flow curves for each cross section within the target river segment;

[0010] Based on the topographic data of each section and the daily average water level to daily average flow curve, the hydraulic parameters of each sub-river section under different characteristic flow rates were obtained.

[0011] Based on the hydraulic parameters of each sub-river section under different characteristic flow rates, the amplitude attenuation factor and hysteresis phase angle of the N-1 sub-river sections below the inlet section are obtained, and the daily regulating wave attenuation distance under different scheduling conditions is also obtained.

[0012] Based on the amplitude attenuation factor and lag phase angle of the N-1 sub-river sections below the inlet section, as well as the attenuation distance of the daily regulating wave under different scheduling conditions, the influence amplitude and timing of the daily regulating wave at a specific location under different scheduling conditions are obtained.

[0013] Furthermore, the method for obtaining the hydraulic parameters of each sub-river segment under different characteristic flow rates based on the topographic data of each cross section and the daily average water level-daily average flow relationship curve is as follows:

[0014] Based on the flow characteristics of the inlet hydrological stations in the river section, three levels of characteristic flow are selected: flood, medium water and low water. According to the water flow distribution characteristics along the river, different characteristic flows at each section along the river are determined by flow conservation.

[0015] Based on the different characteristic flows of each cross section, and combined with the daily average water level to daily average flow relationship curve, the water level under different characteristic flows is determined. Then, the water level and the topographic data of each cross section are combined to calculate the cross section water flow area and cross section water surface width under different characteristic flows.

[0016] Based on the cross-sectional flow area and cross-sectional water surface width under different characteristic flow rates, the cross-sectional flow velocity and cross-sectional water depth under different characteristic flow rates are obtained;

[0017] For N-1 sub-river segments and different characteristic flows, the average flow velocity, average water depth, average Froude number, and average gradient of each sub-river segment under different characteristic flows are obtained as hydraulic parameters of each sub-river segment under different characteristic flows.

[0018] Furthermore, the formulas for calculating the average flow velocity, average water depth, average Froude number, and average gradient within each sub-river segment under different characteristic flow conditions are as follows:

[0019]

[0020]

[0021] In the formula, Let be the average water depth in the j-th sub-segment under the i-th characteristic flow level. Let be the average flow velocity within the j-th sub-segment under the i-th level characteristic flow. Let Froude number be the average Froude number in the j-th sub-segment under the i-th characteristic flow level. Let be the average gradient within the j-th sub-river segment under the i-th level characteristic flow. These are the inlet and outlet cross-sectional water depths of the j-th sub-river segment under the i-th characteristic flow rate. denoted as , and respectively as the inlet and outlet velocities of the j-th sub-segment under the i-th characteristic flow rate, where g is the acceleration due to gravity. Let Δx be the water level difference between the upper and lower sections of the j-th sub-river segment under the i-th characteristic flow rate. j Let be the length of the j-th sub-segment, i = 1 to 3, j = 1 to N-1.

[0022] Furthermore, the method for obtaining the daily regulating wave attenuation distance under various scheduling conditions based on the hydraulic parameters of each sub-river section under different characteristic flow rates is as follows:

[0023] Obtain the water level and flow velocity processes at the river inlet section;

[0024] Based on the hydraulic parameters of each sub-river segment under different characteristic flow rates, the amplitude attenuation factor and hysteresis phase angle of the N-1 sub-river segments below the inlet section are obtained;

[0025] Under each characteristic flow rate, for each regulation scheme, the water level and velocity amplitude of N-1 sections below the inlet section are obtained based on the water level process and velocity process of the inlet section, as well as the amplitude attenuation factor and hysteresis phase angle. Various daily regulation schemes are combined with different characteristic flow rates to form several scheduling conditions, and the water level and velocity amplitude of each section under each scheduling condition are obtained.

[0026] To obtain the daily regulating wave attenuation distance of a target river section under a certain working condition, specifically: for a certain section G under a certain working condition, compare the water level wave amplitude and flow velocity wave amplitude of section G with the allowable water level wave amplitude critical threshold and flow velocity wave amplitude critical threshold, respectively. If the water level wave amplitude of section G is less than the water level wave amplitude critical threshold while the water level wave amplitude of its upstream section is greater than the water level wave amplitude critical threshold, and the flow velocity wave amplitude of section G is less than the flow velocity wave amplitude critical threshold while the flow velocity wave amplitude of its upstream section is greater than the flow velocity wave amplitude critical threshold, then the daily regulating wave attenuation distance of the river section under this working condition is considered to be the distance from the inlet section to section G.

[0027] The formulas for calculating the water level amplitude and velocity amplitude at N-1 sections below the inlet section are as follows:

[0028]

[0029] In the formula, Let $\frac{i}{j}$ represent the water level amplitude and velocity amplitude at the $j$-th cross-section under the $i$-th characteristic flow rate. ΔV1 i These represent the water level amplitude and flow velocity amplitude caused by daily regulation disturbances at the inlet section of the river segment under Class I flow conditions. Let be the amplitude attenuation factor of the k-th sub-segment under the i-th level characteristic flow, where i = 1 to 3, j = 2 to N;

[0030] Repeat the steps described above to obtain the daily regulating wave attenuation distance under a specific operating condition of the target river section until the daily regulating wave attenuation distance under each operating condition of the target river section is obtained.

[0031] Furthermore, based on the hydraulic parameters of each sub-river segment under different characteristic flow rates, the wave amplitude attenuation factor and hysteresis phase angle in N-1 sub-river segments below the inlet section are obtained, and the method for obtaining the daily regulating wave attenuation distance under different scheduling conditions is as follows:

[0032] The formulas for calculating the wave amplitude attenuation factor and hysteresis phase angle within the N-1 sub-segments below the inlet section are as follows:

[0033]

[0034] In the formula, Let be the attenuation ratio of the fluctuation amplitude generated in the j-th sub-segment under the i-th level characteristic flow. Δx represents the phase lag angle generated in the j-th sub-segment under the i-th characteristic flow rate, and ω represents the wave frequency generated by the daily regulation of the power station; j Let be the distance between the inlet and outlet of the j-th sub-river segment, where i = 1 to 3 and j = 1 to N-1;

[0035] in, The calculation formula is:

[0036]

[0037] parameter The calculation formula is:

[0038]

[0039] In the formula, Let Frudd be the average Frudd number of the j-th sub-segment under the i-th flow level. Let be the average flow velocity of the j-th sub-segment under the i-th flow level. Let be the average water depth of the j-th sub-segment under the i-th flow level. Let be the average gradient of the j-th sub-river segment under the i-th level flow rate.

[0040] Furthermore, the method for obtaining the amplitude and timing of the daily regulation wave impact at a specific location under different scheduling conditions is as follows:

[0041] Based on the length of each sub-segment, obtain the sub-segment M where a specific location is located within the target river segment, and obtain the distance ΔL between the specific location and the inlet section M of the sub-segment M.

[0042] For a given scheduling condition, the water level process and flow velocity process at ΔL downstream of section M are obtained based on the amplitude attenuation factor and the lag phase angle, respectively. Furthermore, based on the water level process and flow velocity process at ΔL downstream of section M, the maximum flow velocity, maximum navigation depth, and the timing of the occurrence of the maximum flow velocity and maximum navigation depth caused by the daily regulation wave of the hydropower station at a specific location are obtained.

[0043] The timing of the occurrence of instantaneous additional drop, instantaneous total drop, and instantaneous maximum additional drop at a specific location is obtained based on the amplitude attenuation factor and the hysteresis phase angle.

[0044] The maximum flow velocity, maximum navigation depth, instantaneous additional drop, and instantaneous total drop at a specific location under the scheduling conditions are taken as the daily control wave influence amplitude at that specific location under the scheduling conditions. The timing of the occurrence of the maximum flow velocity and maximum navigation depth at a specific location under the scheduling conditions, and the timing of the occurrence of the instantaneous maximum additional drop are taken as the influence timing of the specific location under the scheduling conditions.

[0045] For several other scheduling conditions, jump to the step of obtaining the sub-segment M of the target river segment based on the daily regulating wave influence amplitude, until the daily regulating wave influence amplitude and timing of the specific location under all scheduling conditions are obtained.

[0046] Furthermore, the formulas for calculating the water level and velocity processes at ΔL downstream of section M under a specific scheduling condition are as follows:

[0047]

[0048] in, The water level at section M without daily regulation interference under flow rate i. Let M be the average flow velocity of the Mth sub-river segment under the i-th flow level. The gradient within sub-river segment M at flow rate i, excluding diurnal regulating wave interference. and Let be the amplitude attenuation factor and phase lag angle caused by the distance ΔL at flow rate i. Let be the amplitude attenuation factor for the k-th sub-segment under the i-th flow level. Let ω be the phase lag angle of the k-th sub-river segment under the i-th level flow rate, ω be the wave frequency generated by the daily regulation of the hydropower station, and t be the time. ΔV1 represents the water level fluctuation amplitude at the inlet section caused by daily regulation disturbances under Class i flow conditions. i The velocity amplitude at the inlet section caused by daily regulation disturbance at flow rate i, where i = 1 to 3;

[0049] The maximum flow velocity at a specific location caused by the daily regulation wave of the power station is:

[0050]

[0051] Maximum navigation depth is:

[0052]

[0053] Among them, Z b This refers to the elevation of the riverbed at the edge of the navigation channel.

[0054] The timing of the occurrence of maximum current velocity and maximum navigation depth is as follows:

[0055]

[0056] The instantaneous additional drop caused by the daily regulation wave of the power station at a specific location under different dispatching conditions is as follows:

[0057]

[0058] The instantaneous total ratio is then:

[0059]

[0060] in, These represent the amplitude attenuation factor and phase lag angle caused by distance ΔL at section M compared to section M, respectively, under flow rate i.

[0061] The timing of the instantaneous maximum additional drop is:

[0062]

[0063] A method for predicting the daily attenuation variation of regulating waves in a hydropower station includes:

[0064] The module selects N cross-section locations within the potential influence range of the hydropower station's daily regulating wave for the target river section and divides the river section into N-1 sub-segments, while simultaneously acquiring topographic data for each cross-section.

[0065] Plot the daily average water level to daily average flow curves for each cross section within the target river segment;

[0066] Based on the topographic data of each section and the daily average water level to daily average flow curve, the hydraulic parameters of each sub-river section under different characteristic flow rates were obtained.

[0067] Based on the hydraulic parameters of each sub-river section under different characteristic flow rates, the amplitude attenuation factor and hysteresis phase angle of the N-1 sub-river sections below the inlet section are obtained, and the daily regulating wave attenuation distance under different scheduling conditions is also obtained.

[0068] Based on the amplitude attenuation factor and lag phase angle of the N-1 sub-river sections below the inlet section, as well as the attenuation distance of the daily regulating wave under different scheduling conditions, the influence amplitude and timing of the daily regulating wave at a specific location under different scheduling conditions are obtained.

[0069] An electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the above-described method for predicting the daily regulation wave attenuation along the path of a hydropower station.

[0070] A non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-described method for predicting the daily regulation wave attenuation along the path of a hydropower station.

[0071] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0072] This invention proposes a method and apparatus for predicting the attenuation of daily regulating waves along the course of a hydropower station. Several characteristic cross-sections are selected within the target river section. Using a long series of water level and flow observation data, the water level-flow relationship curves for each cross-section are determined. Characteristic flow rates at various levels are selected during the dry, medium, and flood seasons. Hydraulic parameters such as water depth and velocity at each characteristic cross-section are calculated. Finally, based on these cross-sectional hydraulic parameters and the parameters of the daily regulating wave generated by the power station at the river inlet, the attenuation of the daily regulating wave along the course of the river is predicted. This method not only allows for the rapid determination of the attenuation distance of the daily regulating wave downstream of the power station based on actual scheduling plans and hydrological information, but also determines the magnitude of the impact of the daily regulating wave on key locations downstream of the dam, such as the values ​​of maximum flow velocity, maximum navigation depth, and maximum gradient, as well as the timing of their periodic occurrences. Compared to conventional physical or mathematical modeling methods, this method has the advantages of requiring less topographic data, being simple to operate, low-cost, and highly efficient, and also has good reliability. It provides a new tool for the planning and design of hydropower stations and the selection of scheduling schemes for existing power stations. Attached Figure Description

[0073] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and are intended to explain the invention, but do not constitute an undue limitation thereof. In the drawings:

[0074] Figure 1 This is a flowchart of the method for predicting the daily regulation wave attenuation along the path of a hydropower station according to the present invention;

[0075] Figure 2 This is a location map of each station along the river section in an embodiment of the present invention;

[0076] Figure 3 This is a graph showing the relationship between the daily average water level and the daily average flow rate at each hydrological station in this embodiment of the invention.

[0077] Figure 4 This is a graph showing the measured amplitude attenuation changes at four stations, A, B, C, and E, in an embodiment of the present invention.

[0078] Figure 5 This is a comparison chart of the measured wave amplitude attenuation ratio and the calculated wave amplitude attenuation ratio for each sub-river segment in the embodiments of the present invention;

[0079] Figure 6 This is a schematic diagram of the method for predicting the daily attenuation change of the regulating wave in a hydropower station according to the present invention. Detailed Implementation

[0080] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0081] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0082] Example 1

[0083] Example 1 provides a method for predicting the daily attenuation variation of regulating waves in a hydropower station, comprising the following steps:

[0084] Step S1: For the target river section, select N cross-section locations within the possible influence range of the daily regulation wave of the hydropower station and divide the river section into N-1 sub-river sections, while obtaining the topographic data of each cross-section.

[0085] Step S2: Plot the daily average water level to daily average flow curve for each cross section within the target river segment;

[0086] Step S3: Based on the topographic data of each section and the daily average water level to daily average flow relationship curve, obtain the hydraulic parameters of each sub-river section under different characteristic flow rates;

[0087] Step S4: Based on the hydraulic parameters of each sub-river section under different characteristic flow rates, obtain the wave amplitude attenuation factor and hysteresis phase angle in N-1 sub-river sections below the inlet section, and obtain the daily regulating wave attenuation distance under different scheduling conditions.

[0088] Step S5: Based on the wave amplitude attenuation factor and hysteresis phase angle in the N-1 sub-river sections below the inlet section and the daily regulation wave attenuation distance under different scheduling conditions, obtain the daily regulation wave influence amplitude and timing at a specific location under different scheduling conditions.

[0089] The method provided in this embodiment for predicting the attenuation of daily regulating waves along the course of a hydropower station is based on the characteristic that the amplitude of daily regulating waves is relatively small compared to the depth of the river channel. It proposes a simplified process for solving the one-dimensional flow motion equation of an open channel, thereby enabling quantitative prediction of the impact of daily regulating waves on downstream waterways. Its features include low data requirements and computational workload, ease of application and high reliability, and easy promotion.

[0090] In this embodiment, in step S1, for the target river section, N cross-sectional locations are selected within the influence range of the hydropower station's daily regulating wave, and the river section is divided into N-1 sub-segments. The method for obtaining topographic data for each cross-section is as follows:

[0091] Step S1.1: For the target river section, select N cross-sectional locations within the potential influence range of the hydropower station's daily regulating waves. These locations should include hydrological or water level stations, as well as upstream or downstream of tributary confluences, with a cross-sectional spacing Δx. j (j=1~N-1) should be as moderate as possible, cross-sectional width B j (j=1~N) should be as close as possible to the average width of the river channel within the river segment, where j is the subscript, B j Let Δx be the width of the j-th cross section. j This is the distance between the j-th cross-section and the (j+1)-th cross-section;

[0092] Step S1.2: For each selected cross section, observe the topography of each cross section along the direction perpendicular to the riverbank. The observation range includes both above and below water and should reach the inundation range of the highest flood level in previous years. The topographic data is stored in the form of distance from the starting point to the elevation.

[0093] Step S1.3: For the target river segment, divide the river segment into N-1 sub-segments using the selected N cross sections.

[0094] In step S1.1 of this embodiment, when selecting the cross-section, if the hydrological stations in the target river section are densely distributed, there is no need to select other cross-sections; the cross-section can be selected at the hydrological station location. If there are few hydrological stations in the target river section, cross-sections can be selected starting from the initial hydrological station at intervals of 30 to 50B (B being the river width). If the hydrological stations in the target river section are evenly distributed and there are tributary confluences in the target river section, then cross-sections should be selected not only at the hydrological stations but also at the river confluences. If there are no tributaries, then only cross-sections need to be selected at the hydrological stations. Although natural rivers are generally non-uniform flows, since the target river section is divided into several sub-segments, and the width of the inlet and outlet cross-sections of each sub-segment is close to the average width of the river channel, each sub-segment tends to be uniform. Therefore, each sub-segment can be approximated as a constant uniform flow.

[0095] In this embodiment, the method for plotting the daily average water level to daily average flow curve of each cross section within the target river section in step S2 is as follows:

[0096] Step S2.1: For N cross sections within the target river section, collect and calculate the daily average flow of each cross section. The daily average flow of the cross section where the hydrological station is located is directly obtained by taking the daily average of the observed values. If there is a diversion between the cross section and the upstream hydrological station, the daily average flow of the cross section should be the flow of the upstream hydrological station minus the daily average flow of the diversion of the tributary. If there is a confluence between the cross section and the upstream hydrological station, the flow of the cross section should be the flow of the upstream hydrological station plus the daily average flow of the confluence of the tributary.

[0097] Step S2.2: For N cross sections within the target river section, collect and calculate the daily average water level of each cross section. The daily average water level of the cross section where the water level station is located is directly obtained by taking the daily average of the station's observation values. For cross sections where the water level station is not located, it is necessary to conduct continuous water level observations for one month for each of the different characteristic flows, and then take the daily average of the observed water levels. In this embodiment, the different characteristic flows refer to the dry season flow, the medium-water season flow, and the flood season flow.

[0098] Step S2.3: Using the daily average flow and daily average water level data of each cross section, use Excel to fit the daily average water level to daily average flow curve of each cross section in the form of a quadratic polynomial.

[0099] In step S2.1 of this embodiment, the daily average flow rate of the cross section other than the hydrological station can be taken from the daily average flow rate Q0 of the upstream hydrological station of the cross section. If there is a tributary divergence and confluence phenomenon between the cross section and the hydrological station, and the daily average flow rate of the divergence is q1 and the daily average flow rate of the confluence is q2, then the flow rate of the cross section Q = Q0 - q1 + q2.

[0100] In this embodiment, the method for obtaining the hydraulic parameters of each sub-river segment under different characteristic flow rates in step S3 is as follows:

[0101] Step S3.1: For the target river section, based on the flow characteristics of the inlet hydrological station within the river section, select three levels of characteristic flow Q for the flood season, medium-water season, and dry season. i (i = 1 to 3), and based on the characteristics of water flow distribution along the route, the three-level characteristic flow rates of each section along the route are determined according to the principle of flow conservation;

[0102] Step S3.2: For each cross-section, determine the water level under each characteristic flow rate by combining the three-level characteristic flow rate with the daily average water level-daily average flow rate relationship curve. Then, by combining water level and cross-sectional topographic data, the cross-sectional area of ​​each section under each characteristic flow rate is calculated. Cross-sectional water surface width The principle of cross-sectional area calculation is to divide the cross-section of the water passage into several small trapezoids, and finally calculate the sum of the areas of the small trapezoids, which is the cross-sectional area.

[0103] Step S3.3: Calculate the cross-sectional water flow area using the parameters from step S3.2. and cross-sectional water surface width Calculate the cross-sectional velocity at each section under the third-order characteristic flow rate. water depth The cross-sectional velocity is the ratio of the characteristic flow rate to the cross-sectional area of ​​the water flow at that flow rate level, i.e. Cross-sectional water depth It is the ratio of cross-sectional area to cross-sectional width, i.e.

[0104] Step S3.4: For N-1 sub-river segments and the three-level characteristic flow, calculate the average flow velocity in each sub-river segment under the i-th level characteristic flow. Average water depth Average Frude Number and average ratio

[0105] Average flow velocity within the sub-river section The average flow velocity across the upper and lower cross sections, and the average water depth. This is the average water depth across the upper and lower cross sections.

[0106] In step S3.1 of this embodiment, the selected characteristic flow levels are the three characteristic flow levels Q for the flood season, the medium-water season, and the dry season. i (i = 1 to 3), flood characteristic flow Q 1 A flood flow rate with a frequency of 5% (once in 20 years) can be selected, and the characteristic flow rate of medium-water is Q. 2 The multi-year average flow rate and the low-water characteristic flow rate Q can be used. 3 The low-water flow level with a multi-year guarantee rate of 90% to 98% can be selected based on the waterway guarantee rate. The specific selection scheme can also be adjusted according to actual application.

[0107] In step S3.1 of this embodiment, the formulas for calculating the average flow velocity, average water depth, average Froude number, and average gradient in each sub-river segment under different characteristic flow rates are as follows:

[0108]

[0109] In the formula, Let be the average water depth in the j-th sub-segment under the i-th characteristic flow level. Let be the average flow velocity within the j-th sub-segment under the i-th level characteristic flow. Let Froude number be the average Froude number in the j-th sub-segment under the i-th characteristic flow level. Let be the average gradient within the j-th sub-river segment under the i-th level characteristic flow. These are the inlet and outlet cross-sectional water depths of the j-th sub-river segment under the i-th characteristic flow rate. denoted as , and respectively as the inlet and outlet velocities of the j-th sub-segment under the i-th characteristic flow rate, where g is the acceleration due to gravity. Let Δx be the water level difference between the upper and lower sections of the j-th sub-river segment under the i-th characteristic flow rate. j Let be the length of the j-th sub-segment, i = 1 to 3, j = 1 to N-1.

[0110] In this embodiment, in step S4, based on the hydraulic parameters of each sub-river segment under different characteristic flow rates, the wave amplitude attenuation factor and hysteresis phase angle of N-1 sub-river segments below the inlet section are obtained, and the method for obtaining the daily regulating wave attenuation distance under different scheduling conditions is as follows:

[0111] Step S4.1: Assuming that under the three characteristic flow levels of dry season, medium water season, and flood season, the daily regulating wave of the power station is a sine wave caused by the periodic turbine switching or supplementary turbine operation, the resulting water level or flow process at the downstream river inlet section is expressed as follows:

[0112] or

[0113] in, The water level at the inlet section of the river segment under Class I flow conditions when there is no daily regulation interference. The water level fluctuation amplitude caused by daily regulation disturbance at the inlet section of the river section under Class I flow; The flow rate at the inlet section of the river segment under Class I flow conditions, without daily regulation interference. This refers to the flow amplitude caused by daily regulation disturbances at the river inlet section under flow level i. If only the water level or flow process at the inlet section is known, the flow or water level process expression can be derived from the water level-flow relationship curve of that section. Similarly, the velocity process V1 at the river inlet section can be derived from the flow process. i =V1 i' +ΔV1 i sin(ωt), where V1 i' ΔV1 represents the flow velocity at the inlet section of the river segment under Class i flow conditions without daily regulation disturbance. i The velocity amplitude caused by daily regulation disturbance at the inlet section of the river segment under Class i flow rate.

[0114] Step S4.2: For each characteristic flow level, calculate the wave amplitude attenuation factor in the N-1 sub-river segments below the inlet section. and lag phase angle Where i = 1 to 3 represents the characteristic flow, and j = 1 to N-1 represents the sub-river segment;

[0115] Step S4.3: For each regulation scheme, calculate the water level and velocity amplitude at N-1 cross-sections below the inlet cross-section. in The water level and velocity amplitude of the j-th cross section under the i-th level characteristic flow (j = 2 ~ N) are respectively. The above process can be carried out under each level of characteristic flow, but the parameters are different. If there are m daily regulation schemes, after combining with the three levels of characteristic flow, 3m calculation conditions are formed. A total of 3m(N-1) calculations are required in N-1 sub-river segments.

[0116] Step S4.3: For the water level and velocity amplitude determined in step S4.3, successively compare the water level and velocity amplitude of each cross-section with the allowable water level amplitude critical threshold δ. Z Critical threshold of flow velocity amplitude δ V In comparison, the daily regulating wave attenuation distance of the river section under each scheduling condition is obtained;

[0117] To obtain the daily regulating wave attenuation distance of a target river segment under a specific operating condition, the following steps are taken: For a specific cross-section G under a given operating condition, the water level wave amplitude and velocity wave amplitude of cross-section G are compared with the allowable critical thresholds for water level wave amplitude and velocity wave amplitude, respectively. If the water level wave amplitude of cross-section G is less than the critical threshold while the water level wave amplitude of its upstream cross-section is greater than the critical threshold, and the velocity wave amplitude of cross-section G is less than the critical threshold while the velocity wave amplitude of its upstream cross-section is greater than the critical threshold, then the daily regulating wave attenuation distance of the river segment under this operating condition is considered to be the distance from the inlet cross-section to cross-section G, i.e.

[0118] By repeatedly executing the steps of the method for obtaining the daily regulating wave attenuation distance under a specific operating condition in a target river segment, the daily regulating wave attenuation distance under different regulating operating conditions can be determined. Where i = 1 to 3 represents the characteristic flow level. This represents the scheduling scheme.

[0119] In step S4.2 of this embodiment, the formulas for calculating the wave amplitude attenuation factor and hysteresis phase angle in the N-1 sub-segments below the inlet section are as follows:

[0120]

[0121] In the formula, Let be the attenuation ratio of the fluctuation amplitude generated in the j-th sub-segment under the i-th level characteristic flow. Let ω be the phase lag angle generated in the j-th sub-segment under the i-th level characteristic flow, and let ω be the wave frequency generated by the daily regulation of the power station, which is a setpoint determined by the dispatching scheme; Δx j Let j be the distance between the inlet and outlet of the j-th sub-river segment;

[0122] in, The calculation formula is:

[0123]

[0124] In the above formula, the parameters The following formula can be used to calculate:

[0125]

[0126] In the formula, Let Frudd be the average Frudd number of the j-th sub-segment under the i-th flow level. Let be the average flow velocity of the j-th sub-segment under the i-th flow level. Let be the average water depth of the j-th sub-segment under the i-th flow level. Let be the average gradient of the j-th sub-river segment under the i-th level flow rate.

[0127] In this embodiment, the method for obtaining the amplitude and timing of the daily adjustment wave impact at a specific location under different scheduling conditions in step S5 is as follows:

[0128] Step 5.1: For a specific location within a river segment, such as a wharf, anchorage, or key navigation section (shoal or dangerous shoal) at a distance 's' from the river segment's inlet, determine the sub-segment of that location. Then the cross-section is located in the Mth sub-river segment, and the distance from the Mth cross-section is...

[0129] Step 5.2: For a given scheduling condition, calculate the water level process and flow velocity process at ΔL downstream of the Mth cross section, which can be written as follows: in, The water level at section M without daily regulation disturbance at flow rate i is obtained by combining the characteristic flow rate level with the water level-flow rate relationship at section M. Let M be the average flow velocity of the Mth sub-river segment under the i-th flow level. The amplitude of the water level or flow velocity wave is determined by the amplitude attenuation factor and the lag phase angle of all sub-river segments along the course, i.e. and Let be the amplitude attenuation factor and phase lag angle caused by distance ΔL at flow rate i, and let be the maximum flow velocity at position s caused by the daily regulation wave of the power station. Maximum navigation depth is (Z b The elevation of the riverbed at the edge of the navigation channel (where the maximum flow velocity and maximum navigation depth occur) is...

[0130] Step 5.3: The instantaneous additional gradient at a specific location caused by the daily regulation wave of the hydropower station can be expressed by formula... To calculate, the instantaneous total decrease is: Among them These represent the amplitude attenuation ratio and phase lag angle caused by the distance ΔL at section M, respectively. For the gradient within sub-river segment M at flow rate i without diurnal regulating wave interference, the timing of the occurrence of the instantaneous maximum additional gradient can be expressed by the formula. Calculation. Repeat step 5.3 to calculate the amplitude and timing of the daily control wave impact at a specific location under different operating conditions.

[0131] In step 5.2 of this embodiment, Calculated by the following formula:

[0132]

[0133] In the formula, ΔL is the distance from a specific location to the Mth cross-section. Determined by the characteristic flow rate and the hydraulic factors within the Mth sub-segment, the calculation formula is as follows:

[0134]

[0135] in,

[0136]

[0137]

[0138] In the formula, Let Froude number be the average Froude number of the Mth sub-segment under the i-th flow level. Let M be the average water depth in the Mth sub-segment under the i-th characteristic flow rate. Let M be the average gradient of the Mth sub-river segment under the i-th flow level. Let M be the average flow velocity of the Mth sub-segment under the i-th flow level. Let be the average water depth of the Mth sub-segment under the i-th flow rate.

[0139] Step 5.4: Take the maximum current speed, maximum navigation depth, instantaneous additional drop, and instantaneous total drop at a specific location under the scheduling conditions as the daily control wave influence amplitude at that specific location under the scheduling conditions, and take the timing of the occurrence of the maximum current speed and maximum navigation depth at a specific location under the scheduling conditions, and the timing of the occurrence of the instantaneous maximum additional drop as the influence timing of the specific location under the scheduling conditions.

[0140] Step 5.5: For several other scheduling conditions, proceed to the step of obtaining the sub-segment M of the target river segment based on the daily regulating wave impact amplitude, until the daily regulating wave impact amplitude and timing of the specific location under all scheduling conditions are obtained.

[0141] This invention proposes a method for predicting the attenuation of daily regulating waves along the course of a hydropower station. Specifically, it involves selecting several cross-sections within a target river section, using long-term series of water level and flow observation data to determine the water level-flow relationship curves for each cross-section, selecting characteristic flow rates at each stage during the dry, medium, and flood seasons, and calculating hydraulic parameters such as water depth and velocity at each cross-section under these characteristic flow rates. Finally, based on these cross-section hydraulic parameters and the parameters of the daily regulating waves generated by the power station at the river inlet, the attenuation of the daily regulating waves along the course of the station is predicted. This method not only allows for the rapid determination of the attenuation distance of the daily regulating waves downstream of the power station based on actual scheduling plans and hydrological information, but also determines the magnitude of the impact of the daily regulating waves on key locations downstream of the dam, such as the values ​​of maximum flow velocity, maximum navigation depth, and maximum gradient, as well as the timing of their periodic occurrences. Compared to conventional physical or mathematical modeling methods, this method has advantages such as requiring less topographic data, being simpler to operate, lower cost, and higher efficiency, and also exhibits better reliability. It provides a new tool for the planning and design of hydropower stations and the selection of scheduling schemes for existing power stations.

[0142] The following describes in detail, with reference to the accompanying drawings, a specific implementation scheme of a method for predicting the daily attenuation variation of regulating waves in a hydropower station, which relates to the present invention.

[0143] The hydrological data used in this embodiment are the daily average flow and daily average water level observation data of a certain river section from February 7 to March 15, 2016. This period is the dry season for this river section, and hydrological stations are located at both the river inlet and outlet. This embodiment only uses the dry season flow as the characteristic flow for illustration, and the daily regulation scheme is a certain scheme n. Furthermore, this embodiment only calculates the attenuation distance of the water level wave amplitude, and does not calculate the amplitude and timing of the influence of the daily regulation wave on a specific location.

[0144] The method for predicting the daily attenuation variation of regulating waves in a hydropower station provided in this embodiment includes the following steps:

[0145] Step S1: For the target river section, select N cross-sectional locations within the daily regulation wave influence range of the hydropower station and divide the river section into N-1 sub-segments, while acquiring the topographic data of each cross-section.

[0146] Depend on Figure 2As can be seen, in this embodiment, there are three hydrological stations in the river section: Station A, Station C, and Station F. Station A not only houses a hydrological station but also a hydropower station. Stations B, D, and E are located at the river confluence and branching points. Stations B, D, and E are equipped with temporary daily regulating wave observation gauges, providing 24 water level observations per day. Therefore, six cross-sections were ultimately selected for this river section, downstream of Stations A, B, C, D, E, and F. The distances from Station A to each of these stations (excluding Station A) are 36.63 km, 57.96 km, 76.06 km, 127.9 km, and 146.2 km, respectively. Based on the selected cross-sections, the topography of each cross-section was observed along the direction perpendicular to the riverbank, and the topographic data was stored in the form of distance from starting point to elevation. The river section was then divided into five sub-sections based on the selected cross-sections.

[0147] Step S2: Plot the daily average water level to daily average flow curve for each section within the target river segment.

[0148] Stations A, C, and F in this river section are hydrological stations; therefore, the daily average flow and daily average water level at the cross-sections of stations A, C, and F can be directly obtained by taking the daily average of the observed values. Stations B, D, and E are not hydrological stations; therefore, water level observations were conducted at the cross-sections of stations B, D, and E for 38 days, and the daily average water level was obtained by taking the daily average of the observed data. The daily average flow at the cross-sections of stations B, D, and E can be obtained by using the daily average flow of their adjacent hydrological stations, based on the confluence and diversion characteristics of their respective river sections. Finally, the daily average water level-daily average flow relationship curves for each cross-section are plotted. Due to space limitations, this embodiment only provides the water level-flow relationship curves for stations A, C, and F as shown below. Figure 3 As shown.

[0149] Step S3: Based on the topographic data of each section and the daily average water level to daily average flow curve, obtain the hydraulic parameters of each sub-river section under different characteristic flow rates.

[0150] Due to space limitations, this embodiment only selects the low-water flow as the characteristic flow. Hydrological data shows that the low-water flow in this river section was 6700 m³ / h from February 7th to March 15th, 2016. 3 / s. In this embodiment, the amplitude attenuation changes are calculated at cross sections A, B, C, D, E, and F. The detailed calculation process of the hydraulic parameters for each sub-river segment is not described here. Based on the data from each cross section, the average water depth within sub-river segments AB, BC, CD, DE, and EF is calculated. Average flow rate Average Frude Number and average ratio The specific calculation results are shown in Table 1 below.

[0151] Table 1 Calculation table of parameters for each sub-river section

[0152]

[0153] Step S4: Obtain the daily regulating wave attenuation distance under different scheduling conditions based on the hydraulic parameters of each section under different characteristic flow rates.

[0154] This embodiment analyzes the attenuation distance of water level wave amplitude. In this embodiment, δ Z =0.08m, ΔZ1 =0.28m. This embodiment shows the attenuation changes of the measured water level amplitudes at points A, B, C, and E in this river section over time, as follows: Figure 4 As shown.

[0155] first, Figure 4 Although it is a change in the amplitude of water level fluctuations over time, Figure 4 In this context, the water level amplitude at each station at the same time can be considered as the attenuation change of the amplitude along the path. Since the daily regulating wave propagates from station A, it can be seen that... Figure 4 The water level fluctuation was largest at station A. As the fluctuation spread to station B, it could be seen that... Figure 4 The water level fluctuation amplitude at station B is significantly smaller, and the time it takes for the water level fluctuation amplitude to reach its maximum value is longer than that at station A, indicating a larger phase lag angle. Similarly... Figure 4 The water level fluctuation amplitudes at stations C and E gradually decrease, and the time it takes for the water level fluctuation amplitude to reach its maximum value is longer than that at station B, meaning the phase lag angle gradually accumulates and increases. That is, from Figure 4 It can be seen that the water level fluctuation amplitude gradually decreases from upstream to downstream. At station A, the water level fluctuation amplitude generally fluctuates above 0.20m, while at station B, the amplitude has decreased by about 40%. Finally, by the time it reaches station E, the amplitude is within 0.1m. Furthermore, observing the water level fluctuation amplitude changes at each station, it can be observed that the fluctuation trend gradually stabilizes. In this embodiment, it is possible to... Figure 5 Based on this, the error between the amplitude attenuation ratio calculated by the water level wave amplitude attenuation formula proposed in this embodiment and the measured amplitude attenuation ratio is observed. The results calculated using the water level wave amplitude attenuation formula in this embodiment are given below. In Table 2 below, the variation period of the regulating wave is 24 hours, so the calculated ω data are shown in the table below. a, b, c, d, p, E, and F are the various calculation parameters, Δx is the distance between the inlet and outlet of each sub-river segment, and the finally calculated β is the amplitude attenuation ratio. The specific calculation results for the phase lag angle are shown in Table 2 below.

[0156] Table 2. Calculation of Water Level Amplitude Attenuation Ratio and Phase Lag Angle for Each Sub-River Section

[0157]

[0158] To verify the accuracy of this formula, Table 3 below shows a comparison between the measured water level amplitude attenuation ratios of sub-river segments AB, BC, CD, DE, and EF and the water level amplitude attenuation ratios calculated by the formula. Figure 5 This allows for a more intuitive comparison between the two situations.

[0159] Table 3: Comparison of the attenuation of water level amplitude along the course of the regulating wave.

[0160] A—B BC CD DE EF Measured water level wave amplitude attenuation ratio 0.604 0.875 1.036 0.483 0.714 Calculate the water level wave amplitude attenuation ratio 0.667 0.886 0.794 0.518 0.803 relative error 10.43％ 1.26％ 23.36％ 7.25％ 12.46％

[0161] Comparing the measured and calculated data, it was found that the measured and calculated wave amplitude changes for sub-river segments A-B, BC, D-E, and EF were quite similar, with no significant differences and a relative error within 15%. The measured and calculated wave amplitude changes for sub-river segment CD showed a larger error. This is because the location of section D has sandbars and complex topography, making the water flow at section D not a constant uniform flow. This method approximates the river flow as a constant uniform flow, hence the larger but still relatively accurate error in the measured and calculated wave amplitude changes for sub-river segment CD. Therefore, it can be considered that the formula's description and fitting of the problem are relatively reasonable. Considering all aspects, it can be clearly seen that the wave amplitude does indeed decrease exponentially with distance, reaching a certain level at 6700m. 3 In the case of / s Approximately 127 km beyond, that is, when it propagates to section E, the change in wave amplitude becomes extremely small. It can be assumed that after section E, the impact of the daily regulating wave on ship navigation can be ignored to a certain extent.

[0162] The above embodiments are merely illustrative examples of the technical solution of the present invention. The method for predicting the daily attenuation variation of regulating waves in a hydropower station, as described in the present invention, is not limited to the content described in the above embodiments, but is defined by the scope of the claims. Any modifications, additions, or equivalent substitutions made by those skilled in the art based on these embodiments are within the scope of protection claimed by the claims of the present invention.

Claims

1. A method for predicting the daily attenuation variation of regulating waves along the path of a hydropower station, characterized in that, Includes the following steps: For the target river section, N cross-section locations are selected within the potential influence range of the daily regulating wave of the hydropower station, and the river section is divided into N-1 sub-segments. At the same time, the topographic data of each cross-section is obtained. Plot the daily average water level to daily average flow curves for each cross section within the target river segment; Based on the topographic data of each section and the daily average water level to daily average flow curve, the hydraulic parameters of each sub-river section under different characteristic flow rates were obtained. Based on the hydraulic parameters of each sub-river section under different characteristic flow rates, the amplitude attenuation factor and hysteresis phase angle of the N-1 sub-river sections below the inlet section are obtained, and the daily regulating wave attenuation distance under different scheduling conditions is also obtained. Based on the amplitude attenuation factor and hysteresis phase angle of the N-1 sub-river sections below the inlet section and the attenuation distance of the daily regulating wave under different scheduling conditions, the influence amplitude and timing of the daily regulating wave at a specific location under different scheduling conditions are obtained. The method for obtaining the amplitude and timing of the daily regulation wave impact at a specific location under different scheduling conditions is as follows: Based on the length of each sub-segment, the sub-segment M at a specific location within the target river segment is obtained, along with the distance between that specific location and the inlet section M of that sub-segment M. ; For a given scheduling condition, the downstream section M is obtained based on the amplitude attenuation factor and the hysteresis phase angle. The water level and flow velocity processes at the location, and based on the downstream section M. The water level and flow velocity processes at a specific location are used to obtain the maximum flow velocity, maximum navigation depth, and the timing of the occurrence of the maximum flow velocity and maximum navigation depth caused by the daily regulation wave of the hydropower station. The timing of the occurrence of instantaneous additional drop, instantaneous total drop, and instantaneous maximum additional drop at a specific location is obtained based on the amplitude attenuation factor and the hysteresis phase angle. The maximum flow velocity, maximum navigation depth, instantaneous additional drop, and instantaneous total drop at a specific location under the scheduling conditions are taken as the daily control wave influence amplitude at that specific location under the scheduling conditions. The timing of the occurrence of the maximum flow velocity and maximum navigation depth at a specific location under the scheduling conditions, and the timing of the occurrence of the instantaneous maximum additional drop are taken as the influence timing of the specific location under the scheduling conditions. For several other scheduling conditions, jump to the step of obtaining the sub-segment M of the target river segment based on the daily regulating wave influence amplitude, until the daily regulating wave influence amplitude and timing of the specific location under all scheduling conditions are obtained.

2. The method for predicting the attenuation variation of daily regulating waves along the path of a hydropower station according to claim 1, characterized in that, The method for obtaining hydraulic parameters of each sub-river segment under different characteristic flow rates based on topographic data of each cross section and the daily average water level-daily average flow relationship curve is as follows: Based on the flow characteristics of the inlet hydrological stations in the river section, three levels of characteristic flow are selected: flood, medium water and low water. According to the water flow distribution characteristics along the river, different characteristic flows at each section along the river are determined by flow conservation. Based on the different characteristic flows of each cross section, combined with the daily average water level ~ daily average flow relationship curve, the water level under different characteristic flows is determined. Then, the water level and the topographic data of each cross section are combined to calculate the cross section water flow area and cross section water surface width under different characteristic flows. Based on the cross-sectional flow area and cross-sectional water surface width under different characteristic flow rates, the cross-sectional flow velocity and cross-sectional water depth under different characteristic flow rates are obtained; For N-1 sub-river segments and different characteristic flows, the average flow velocity, average water depth, average Froude number, and average gradient of each sub-river segment under different characteristic flows are obtained as hydraulic parameters of each sub-river segment under different characteristic flows.

3. The method for predicting the daily attenuation variation of the regulating wave along the path of a hydropower station according to claim 2, characterized in that: The formulas for calculating the average flow velocity, average water depth, average Froude number, and average gradient in each sub-river segment under different characteristic flow conditions are as follows: In the formula, for The first characteristic flow under level The average water depth within each section of the river for The first characteristic flow under level Average flow velocity within each river section for The first characteristic flow under level Average number of Frude numbers within each river section for The first characteristic flow under level Average gradient within each river section , They are respectively The first characteristic flow under level The water depth at the inlet and outlet sections of each section of the river. , They are respectively The first characteristic flow under level The flow velocity at the inlet and outlet sections of each river segment It is the acceleration due to gravity. for The first characteristic flow under level The water level difference between the inlet and outlet sections of the Gezi River section For the first The length of each section of the river , .

4. The method for predicting the daily attenuation variation of the regulating wave along the path of a hydropower station according to claim 1, characterized in that, The method for obtaining the daily regulation wave attenuation distance under various scheduling conditions based on the hydraulic parameters of each sub-river segment under different characteristic flow rates is as follows: Obtain the water level and flow velocity processes at the river inlet section; Based on the hydraulic parameters of each sub-river segment under different characteristic flow rates, the amplitude attenuation factor and hysteresis phase angle of the N-1 sub-river segments below the inlet section are obtained; Under each characteristic flow rate, for each regulation scheme, the water level and velocity amplitude of N-1 sections below the inlet section are obtained based on the water level process and velocity process of the inlet section, as well as the amplitude attenuation factor and hysteresis phase angle. Various daily regulation schemes are combined with different characteristic flow rates to form several scheduling conditions, and the water level and velocity amplitude of each section under each scheduling condition are obtained. To obtain the daily regulating wave attenuation distance of a target river section under a certain working condition, specifically: for a certain section G under a certain working condition, compare the water level wave amplitude and flow velocity wave amplitude of section G with the allowable water level wave amplitude critical threshold and flow velocity wave amplitude critical threshold, respectively. If the water level wave amplitude of section G is less than the water level wave amplitude critical threshold while the water level wave amplitude of its upstream section is greater than the water level wave amplitude critical threshold, and the flow velocity wave amplitude of section G is less than the flow velocity wave amplitude critical threshold while the flow velocity wave amplitude of its upstream section is greater than the flow velocity wave amplitude critical threshold, then the daily regulating wave attenuation distance of the river section under this working condition is considered to be the distance from the inlet section to section G. The formulas for calculating the water level amplitude and velocity amplitude at N-1 sections below the inlet section are as follows: In the formula, , They are respectively The first characteristic flow under level Water level fluctuation amplitude and flow velocity fluctuation amplitude at each cross section , They are respectively The amplitude of water level fluctuations and velocity fluctuations caused by daily regulation disturbances at the inlet section of the river section under the grade-level flow rate. for The first characteristic flow under level The amplitude attenuation factor of each river segment ; Repeat the steps described above to obtain the daily regulating wave attenuation distance under a specific operating condition of the target river section until the daily regulating wave attenuation distance under each operating condition of the target river section is obtained.

5. The method for predicting the daily attenuation variation of the regulating wave along the path of a hydropower station according to claim 1, characterized in that, Based on the hydraulic parameters of each sub-river segment under different characteristic flow rates, the wave amplitude attenuation factor and lag phase angle of N-1 sub-river segments below the inlet section are obtained, and the method for obtaining the daily regulating wave attenuation distance under different scheduling conditions is as follows: The formulas for calculating the wave amplitude attenuation factor and hysteresis phase angle within the N-1 sub-segments below the inlet section are as follows: In the formula, for The first characteristic flow under level The attenuation ratio of fluctuation amplitude generated within each sub-river section for The first characteristic flow under level The phase lag angle generated within each sub-river segment The frequency generated by the daily regulation of the power plant; For the first The distance between the inlet and outlet of each section of the river , ; in, , The calculation formula is: ， parameter , , , , The calculation formula is: ， ， ， In the formula, for Level 1 flow The average Frude number of each sub-river segment for Level 1 flow The average flow velocity of each river section for Level 1 flow The average water depth of each section of the river for Level 1 flow The average gradient of each sub-river section.

6. The method for predicting the daily attenuation variation of the regulating wave along the path of a hydropower station according to claim 1, characterized in that: Downstream of section M under a certain scheduling condition The formulas for calculating the water level and flow velocity processes at the location are: in, for The water level at section M under level-one flow without daily regulation interference. for The average flow velocity of the Mth sub-river segment under the Class I flow rate, for The gradient within the sub-river section M under the level flow rate without diurnal regulating wave interference. , , , and for Distance at high flow rate The resulting amplitude attenuation factor and phase lag angle, for Level 1 flow The amplitude attenuation factor of each river segment for Level 1 flow Phase lag angle of each sub-river segment The wave frequency generated by the daily regulation of the hydropower station, For time, for The water level fluctuation amplitude at the inlet section caused by daily regulation disturbances under graded flow conditions. for The velocity fluctuation amplitude at the inlet section caused by daily regulation disturbances at the primary flow rate. ; The maximum flow velocity at a specific location caused by the daily regulation wave of the power station is: ； Maximum navigation depth is: in, This refers to the elevation of the riverbed at the edge of the navigation channel. The timing of the occurrence of maximum current velocity and maximum navigation depth is as follows: The instantaneous additional drop caused by the daily regulation wave of the power station at a specific location under different dispatching conditions is as follows: The instantaneous total ratio is then: in, , They represent Distance at high flow rate The resulting amplitude attenuation factor and phase lag angle; The timing of the instantaneous maximum additional drop is: 。 7. A device for predicting the attenuation variation of daily regulating waves along the path of a hydropower station, characterized in that, include: The module selects N cross-section locations within the potential influence range of the hydropower station's daily regulating wave for the target river section and divides the river section into N-1 sub-segments, while simultaneously acquiring topographic data for each cross-section. The plotting module plots the daily average water level to daily average flow curves for each cross-section within the target river section. Based on the topographic data of each section and the daily average water level to daily average flow curve, the hydraulic parameters of each sub-river section under different characteristic flow rates were obtained. The first acquisition module, based on the hydraulic parameters of each sub-river section under different characteristic flow rates, acquires the wave amplitude attenuation factor and hysteresis phase angle in N-1 sub-river sections below the inlet section, and acquires the daily regulating wave attenuation distance under different scheduling conditions. The second acquisition module, based on the wave amplitude attenuation factor and hysteresis phase angle in N-1 sub-river sections below the inlet section and the daily regulation wave attenuation distance under different scheduling conditions, obtains the influence amplitude and timing of the daily regulation wave at a specific location under different scheduling conditions. The third acquisition module obtains the daily adjustment wave impact amplitude and timing at a specific location under different scheduling conditions as follows: Based on the length of each sub-segment, the sub-segment M at a specific location within the target river segment is obtained, along with the distance between that specific location and the inlet section M of that sub-segment M. ; For a given scheduling condition, the downstream section M is obtained based on the amplitude attenuation factor and the hysteresis phase angle. The water level and flow velocity processes at the location, and based on the downstream section M. The water level and flow velocity processes at a specific location are used to obtain the maximum flow velocity, maximum navigation depth, and the timing of the occurrence of the maximum flow velocity and maximum navigation depth caused by the daily regulation wave of the hydropower station. The timing of the occurrence of instantaneous additional drop, instantaneous total drop, and instantaneous maximum additional drop at a specific location is obtained based on the amplitude attenuation factor and the hysteresis phase angle. The maximum flow velocity, maximum navigation depth, instantaneous additional drop, and instantaneous total drop at a specific location under the scheduling conditions are taken as the daily control wave influence amplitude at that specific location under the scheduling conditions. The timing of the occurrence of the maximum flow velocity and maximum navigation depth at a specific location under the scheduling conditions, and the timing of the occurrence of the instantaneous maximum additional drop are taken as the influence timing of the specific location under the scheduling conditions. For several other scheduling conditions, jump to the step of obtaining the sub-segment M of the target river segment based on the daily regulating wave influence amplitude, until the daily regulating wave influence amplitude and timing of the specific location under all scheduling conditions are obtained.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the method for predicting the daily attenuation change of the regulating wave along the path of a hydropower station as described in any one of claims 1 to 6.

9. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the method for predicting the daily attenuation change of the regulating wave along the path of a hydropower station as described in any one of claims 1 to 6.

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