CN-122022234-A - Long-term scheduling method in water-light storage system considering sediment accumulation and reservoir backwater

CN122022234ACN 122022234 ACN122022234 ACN 122022234ACN-122022234-A

Abstract

The invention relates to the cross field of clean renewable energy utilization, reservoir dispatching and water ecological balance, and discloses a long-term dispatching method in a water light storage system considering sediment accumulation and reservoir backwater. The method comprises the following steps of (1) coupling short-term electric quantity loss characteristics of a system, taking the generated energy and the generation guarantee rate as targets, establishing a water-light accumulation integrated medium-long term scheduling model, (2) simulating two-dimensional non-uniform water-sand numerical values of a plane based on a non-constant shallow water motion equation, a non-uniform sand-sediment diffusion equation and a riverbed deformation equation, and establishing a sediment accumulation and backwater model, (3) coupling the water-light accumulation integrated scheduling model and the sediment accumulation model in a mutual feeding mode, so that the water-light accumulation medium-long term scheduling taking sediment accumulation and reservoir backwater into consideration is realized. According to the invention, a water-light-sand multi-target coupling reservoir operation scheduling model considering multi-source uncertainty and multi-source constraint conditions is constructed, and the linkage of complementary scheduling, sediment accumulation and backwater calculation is realized.

Inventors

WU DI
LIU PAN
YIN SHUHONG
GONG LANQIANG
YU JIYUAN
MA LI
LI LI
LIU ZHEYUAN
GUAN ZHEN
ZOU MINMIN

Assignees

中国电建集团贵阳勘测设计研究院有限公司
华能澜沧江水电股份有限公司
武汉大学

Dates

Publication Date: 20260512
Application Date: 20251216

Claims (7)

1. A method for long-term dispatching in a water light storage system considering sediment accumulation and reservoir backwater is characterized by comprising the following steps: (1) The method comprises the steps of coupling short-term electric quantity loss characteristics of a system, and establishing a water-light-storage integrated medium-long-term scheduling model by taking the generated energy and the generated electricity guarantee rate as targets; (2) Simulating a planar two-dimensional non-uniform water-sediment value based on a non-constant shallow water motion equation, a non-uniform sediment diffusion equation and a riverbed deformation equation, and establishing a sediment accumulation and backwater model; (3) The real-time coupling water-light-storage integrated dispatching and water-sand prevention and control calculation are realized, and the long-term dispatching in the water-light-storage integrated system meeting the sediment accumulation and reservoir backwater requirements is realized.
2. The method for long-term dispatching in a water-light accumulation system considering sediment accumulation and reservoir backwater as claimed in claim 1, wherein the following steps (1): The method for establishing the short-term dispatching model of the water-light-storage integrated system comprises the steps of simulating a power generation plan preparation and real-time dispatching process so as to accurately simulate electric quantity loss and deduce an electric quantity loss function, wherein the electric quantity loss function is as follows: ; wherein: Indicating that the water-light-storage integrated system has water power as power The loss rate of electric quantity at the time of representing Photoelectric discarding; Representing the drawing and accumulating damage; a medium-long term scheduling model of a short-term power loss characteristic of the coupling system is constructed, the optimization targets are as follows: ; Wherein: ; ; in the formula, EP and ER are respectively the generated energy and the generated electricity guarantee rate of the complementary system in the whole scheduling period, I and I are respectively the long-term scheduling period number and the total scheduling period number; , , The average water power output, the actual average photovoltaic output and the electric quantity loss output in the first period are respectively; Indicating that the water-light-storage integrated system has water power as power The electric quantity loss rate is obtained according to a short-term simulation model; ensuring the output for the complementary system; the net output of the complementary system is lower than the number of guaranteed outputs during the whole scheduling period.
3. The method for long-term dispatching in a water and light accumulation system considering sediment accumulation and reservoir backwater as claimed in claim 2, wherein the model constraint conditions comprise water balance constraint, hydropower flow range constraint, hydropower head range constraint, hydropower output range constraint, pumped storage energy storage range constraint and pumped storage energy balance constraint.
4. The method for long-term dispatching in a water-light accumulation system considering sediment accumulation and reservoir backwater as claimed in claim 1, wherein the step (2) is characterized in that: Based on a non-constant shallow water motion equation, a non-uniform sediment diffusion equation and a riverbed deformation equation, two sediment motion forms of suspended substances and bed load and an exchange mechanism of the suspended substances and bed sediment are considered, a planar two-dimensional water-sediment numerical model is constructed, the model considers the influence of upstream water-supply sand grading and local beds Sha Jipei on water-supply sand carrying capacity, the riverbed is divided into a mixed layer, a sedimentation memory layer and an original riverbed in riverbed deformation calculation, and the principle of exchange of the riverbed and the water-supply sand carrying capacity is considered according to respective characteristics; The model adopts a strategy combining the body-attached coordinate transformation and the finite volume method to solve the hydraulic calculation problem under the complex physical boundary condition, wherein the body-attached coordinate transformation is to map an irregular calculation area in a physical plane to a regular rectangular area in the calculation plane through coordinate transformation, so that the application of the boundary condition becomes direct and accurate, and the grid generation and the processing of the boundary condition are greatly simplified; transformation principle: curve coordinates in physical plane , ) And calculating regular coordinates in plane , ) The transformation between follows the Cauchy-Riemann condition: ; after the coordinate transformation is completed, all control equations established in the physical plane are converted into a regular calculation plane to be solved.
5. The method for long-term dispatching in a water-light accumulation system considering sediment accumulation and reservoir backwater as claimed in claim 4, wherein the transformed physical equation is as follows: Water flow continuity equation: ; Equation of motion of water flow: ; Dispersion of the suspended mass diffusion equation: ; the solution process is that the water flow continuous equation and the motion equation are solved in a combined way through a finite volume method, on the basis, the suspended mass continuous equation is solved through the finite volume method, and the riverbed deformation equation and the bed sand composition equation are solved through a difference method.
6. The method for long-term dispatching in a water-light accumulation system considering sediment accumulation and reservoir backwater as claimed in claim 1, wherein the step (3) is characterized in that: on the basis of the existing water-light-storage integrated dispatching model and sediment accumulation and backwater calculation model, key elements and connection nodes for coupling mutual feeding are identified, a water-light-sand integrated system is oriented, a multi-target cooperative reservoir dispatching model is constructed, and a real-time coupling method is provided.
7. The method for long-term dispatching in a water and light accumulation system considering sediment accumulation and reservoir backwater as claimed in claim 6, wherein the real-time coupling of water and light accumulation integrated dispatching and water and sand prevention and control calculation comprises the following steps: 1) In the optimal scheduling process of the water-light-sand integrated system, the water-light accumulation complementary scheduling model and the sediment accumulation and backwater model synchronously execute calculation, namely, in each calculation period, the water-light accumulation model calculates the down-flow rate, the water level change, the power generation and power rejection conditions; 2) The sediment accumulation and backwater model carries out systematic recheck on the elevation and the position of the vertex of the reservoir accumulation delta every five years, if the calculated value exceeds the set threshold value, the characteristic water level scheme is adjusted, and the optimization calculation is carried out again; 3) And after the optimization scheduling of the water-light-sand integrated system is finished, synchronously outputting the optimal running track of the reservoir and the maximum sedimentation height of the reservoir tail under the condition, namely, the optimal running track of the reservoir meeting the overall control requirement of the system.

Description

Long-term scheduling method in water-light storage system considering sediment accumulation and reservoir backwater Technical Field The invention belongs to the cross field of clean renewable energy utilization, reservoir dispatching and water ecological balance, and relates to a long-term dispatching method in a water-light storage (integrated) system considering sediment accumulation and reservoir backwater. Background The reservoir dispatching operation needs to consider the self operation benefit, the cascade hydropower station operation benefit, the water-light storage complementary operation benefit and the reservoir tail sensitive point to influence a plurality of dispatching targets and complex constraint conditions, and is a complex hydraulic engineering problem related to various factors such as reservoir hydrology, waterpower, sediment and the like and various different water resource utilization requirements. The problem not only comprises the content of the joint scheduling and the complementary operation of the water light storage of the cascade reservoir, but also needs to carry out sediment accumulation calculation of the reservoir and reservoir backwater calculation. Silt accumulation is one of the common problems in reservoirs, the accumulation amount of the silt accumulation is related to the sand amount in the reservoir, the flow rate of a reservoir area, backwater and other factors, the backwater accumulation capacity, flood control capacity, power generation efficiency and the like of the reservoir are affected, and backwater of the reservoir is related to the quality and water quantity control of reservoir outlet water and the balance of downstream ecological environment and water demand. At present, the research on long-term dispatching in reservoirs is mostly focused on dispatching characteristic analysis and dispatching strategy formulation of common hydropower hedging wind and light, and the research on a model for coupling sediment accumulation and reservoir backwater is less. Based on the method, the invention provides a method for dispatching the water, the light and the storage integrated system in a medium-long term by considering sediment accumulation and reservoir backwater. Disclosure of Invention The invention aims to solve the problems that the current research on long-term dispatching in reservoirs is mostly focused on dispatching characteristic analysis and dispatching strategy formulation of common hydropower hedging wind and light, and the research on a model for coupling sediment accumulation and reservoir backwater is less. Based on the method, the hydropower station multi-target coupling reservoir operation scheduling model taking water and sand prevention and control as boundary conditions and comprehensively considering the cascade hydropower benefits and the base water light storage complementary benefits is provided, sediment accumulation calculation of reservoirs, reservoir backwater calculation, integrated base water light storage complementary calculation and cascade reservoir group joint scheduling calculation are coupled together to form linkage and mutual feedback on calculation. The technical scheme is that the method for dispatching the water-light storage system for the sediment accumulation and reservoir backwater for a long time comprises the following steps: (1) And the coupling system short-term electric quantity loss characteristic is used for establishing a water-light-storage integrated medium-long-term scheduling model by taking the generated energy and the generated electricity guarantee rate as targets. Firstly, a short-term dispatching model of the water-light-storage integrated system is established, and a power generation plan preparation and real-time dispatching process is simulated so as to accurately simulate electric quantity loss and deduce an electric quantity loss function. The power loss function is as follows: ; wherein: Indicating that the water-light-storage integrated system has water power as power The loss rate of electric quantity at the time of representingPhotoelectric discarding; Representing the suction and accumulation damage. Accordingly, a medium-long term scheduling model of the short-term electric quantity loss characteristic of the coupling system is constructed, and the optimization targets are as follows: ; Wherein: ; ; in the formula, EP and ER are respectively the generated energy and the generated electricity guarantee rate of the complementary system in the whole scheduling period, I and I are respectively the long-term scheduling period number and the total scheduling period number; ,, The average water power output, the actual average photovoltaic output and the electric quantity loss output in the first period are respectively; Indicating that the water-light-storage integrated system has water power as power The electric quantity loss rate is obtained according to a short-term simulation model; ensuri