Hybrid pumping and storage combined operation scheduling method for coupling pumping power generation hydrodynamic simulation

Abstract

The invention provides a hybrid pumping and storage combined operation scheduling method for coupled pumping power generation hydrodynamic simulation for hybrid pumping and storage and an upper reservoir, a lower reservoir, an upper reservoir hydropower station and a lower reservoir hydropower station depending on the hybrid pumping and storage, and the method comprises the following steps: S1, determining a combined operation scheduling boundary condition; s2, establishing an upper reservoir water-wind-light integrated operation scheduling model; s3, establishing a hybrid pumped storage wind-solar storage integrated operation scheduling model; s4, establishing a lower reservoir reverse regulation operation scheduling model; s5, establishing a lower reservoir pumping power generation coupling hydrodynamic force numerical simulation model; and S6, determining a joint operation scheduling scheme after hydrodynamic correction. A coupling hydrodynamic simulation method is adopted to correct the rationality and accuracy of operation scheduling, a reasonable water-wind-light-storage integrated complementary operation scheduling strategy is provided, nesting of hydraulic calculation and upper reservoir power station water-wind-light-storage integrated electric power complementary calculation and nesting of hybrid pumped storage wind-light-storage integrated electric power complementary calculation are achieved, and the operation scheduling efficiency is improved. And a reverse regulation scheduling strategy of the reservoir under mixed pumping and storage is provided.

Description

Technical Field

[0001] The present invention relates to the field of joint operation and dispatching, and in particular to a hybrid pumped-storage wind-solar-storage integrated operation and dispatching, and a hybrid pumped-storage joint operation and dispatching method coupled with pumped-power generation hydrodynamic simulation. Background Art

[0002] Hybrid pumped storage power station (referred to as hybrid pumped storage) is a hydropower station that has both pumped storage and runoff power generation functions. It is an important component of pumped storage power stations and an ideal "high-quality long-term energy storage" method. Hybrid pumped storage has increased installed capacity, enhanced peak-shaving capacity, and long continuous power generation and pumping operation time. It can not only use the abandoned water of the hydropower station to generate electricity and improve the efficiency of water energy utilization, but also can be adjusted daily, weekly, ten-day or even seasonally. It has obvious advantages in serving new energy power generation and can better meet the needs of power systems and clean energy bases for regulation capabilities. Hybrid pumped storage does not require the construction of upper and lower reservoirs, but only requires the construction of a new water transmission and power generation system. It usually does not involve major environmentally sensitive objects, involves less land acquisition and immigration, has rich geological data accumulation, and has low operation and maintenance costs. It is easy to quickly implement construction and exert functional benefits. Under the situation of large-scale development and utilization of new power systems and new energy, hybrid pumped storage will usher in rapid development and effectively promote the development of integrated clean energy bases for water, wind, and solar storage in the basin.

[0003] The hybrid pumped storage and its upper reservoir, lower reservoir, upper reservoir hydropower station, and lower reservoir power station together form a joint system of "2 reservoirs and 3 stations". One of the characteristics of this system is the superposition of water-wind-solar integration and wind-solar-storage integration, that is, the conventional hydropower stations of the upper and lower reservoirs have the conditions for complementing with wind and solar (i.e., water-wind-solar integration), while the hybrid pumped storage can complement the additional wind and solar (i.e., wind-solar-storage integration), and the superposition of the two forms a multi-energy complementary system relationship of water-wind-solar-storage integration. The second characteristic of this system is that the hydraulic calculation of the cascade reservoir and the complementary power calculation of water-wind-solar-storage are nested, that is, the hybrid pumped storage and conventional hydropower stations share the same reservoir, and are coordinated as a group of power sources. Based on the reasonable allocation of the regulating storage capacity of the shared reservoir, the impact of the dynamic fluctuation of the reservoir water level, and the coordinated power transmission of the transmission channel, conventional hydropower stations and hybrid pumped storage are closely linked not only from the hydraulic connection but also from the power connection, forming a complex operation and dispatching system.

[0004] The inlet / outlet of the lower reservoir of the hybrid pumped storage is generally close to the downstream of the dam of the upper reservoir, and is located at the tail of the lower reservoir. Under power generation conditions, the power generation water flows downstream, forming a positive superposition effect with the power generation of the conventional units in the upper reservoir; while the pumping condition will form a reverse flow, and because the pumping flow is large and the reverse flow velocity is also large, the return water of the lower reservoir will not only not be piled up near the inlet / outlet, but will drop rapidly, thus forming a pumping funnel phenomenon. Whether it is the power generation superposition effect or the pumping funnel phenomenon, it will affect the water level along the lower reservoir, the power generation head and the regulating storage capacity, which is manifested in the calculation error between the operation of conventional hydropower and hybrid pumped storage and the actual situation, thus affecting the rationality and accuracy of the hybrid pumped storage joint dispatch. Summary of the invention

[0005] The main purpose of the present invention is to provide a hybrid pumped-storage joint operation scheduling method coupled with pumped-power generation hydrodynamic simulation to solve the problems in the above-mentioned background technology.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is: the method steps are as follows:

[0007] S1. Determine the boundary conditions for joint operation scheduling;

[0008] S2. Establish an integrated operation and dispatching model for water, wind and solar power in the upper reservoir;

[0009] S3. Establish a hybrid pumped-storage wind-solar-storage integrated operation and dispatching model;

[0010] S4. Establish the counter-regulation operation and dispatching model of the lower reservoir;

[0011] S5. Establish a numerical simulation model of the coupling hydrodynamics of pumping power generation in the lower reservoir;

[0012] S6. Determine the joint operation scheduling plan after hydrodynamic correction.

[0013] Preferably, the algorithm calculation process of step S2 is as follows:

[0014] A1. Arrange the basic parameters of the upper reservoir power station, runoff data, complementary wind and solar data, and unit characteristic parameter input data;

[0015] A2. According to the annual operation mode of the upper reservoir power station, annual runoff regulation calculation is carried out to determine the reservoir outflow, water level changes and water storage and release process in each month of the year;

[0016] A3. Count the daily average output of complementary wind and solar power, make fine adjustments to the daily operation and dispatch of the upper reservoir power station in different months, appropriately reduce the hydropower generation flow on the day with large wind and solar power output, appropriately increase the hydropower generation flow on the day with small wind and solar power output, and update the monthly regulation calculation results;

[0017] A4. Carry out the water-wind-solar complementarity calculation of the upper reservoir power station on a daily basis, and nest the power complementarity and hydraulic calculation of the hydropower station;

[0018] A5. The subsequent step S3 is the hybrid pumped storage wind-solar storage daily complementary calculation and step S4 is the lower reservoir daily counter-regulation calculation, which will affect the storage capacity and water level status of the upper and lower reservoirs, thereby affecting the nested results of the hydraulic calculation and power calculation in this step S2. Therefore, a large loop iterative calculation is performed after step S4 until the storage capacity and water level status of the upper and lower reservoirs remain unchanged.

[0019] Preferably, the specific process of step A4 is as follows:

[0020] B1. Calculate the power generation head based on the existing upper reservoir water level and determine the expected output;

[0021] B2. Calculate the wind and solar peak power to be deducted based on the hydropower base load output and channel capacity limit;

[0022] B3. Hydropower is given priority in power generation. All hydropower is sent out, and wind and solar power are sent out using the idle capacity of the channel. The output that can be absorbed by wind and solar power is determined based on the surplus space in the channel, as well as the output that is abandoned;

[0023] B4. Combine the hourly output of wind and solar power to determine the hourly output of hydropower;

[0024] B5. Assuming the power generation flow, calculate the storage capacity and current water level of the upper and lower reservoirs in each time period, and pay attention to the situation where the hybrid pumped storage power generation is blocked. The power generation output and power generation flow of the upper reservoir power station are included in the forward output and forward flow of the hybrid pumped storage;

[0025] B6. Calculate the power generation head loss, power generation head and power generation efficiency of the upper reservoir at each time period;

[0026] B7. Update the power generation flow according to the hydropower output, power generation head and power generation efficiency of the unit;

[0027] B8. Iterate steps B5, B6 and B7 until the power generation flow converges and remains unchanged.

[0028] Preferably, the algorithm calculation process of step S3 is as follows:

[0029] C1. Arrange the basic parameters of hybrid pumped storage, runoff data, complementary wind and solar data, and unit characteristic parameter input data;

[0030] C2. Perform hybrid pumped storage wind-solar-storage complementation calculations on a daily basis, nesting power complementation and hybrid pumped storage hydropower calculations;

[0031] C3. The subsequent step S4 is the intraday counter-regulation calculation of the lower reservoir, which will affect the storage capacity and water level status of the lower reservoir, thereby affecting the nested results of the hydraulic calculation and power calculation in this step 3. Therefore, a large loop iterative calculation is performed after step S4 until the storage capacity and water level status of the lower reservoir remain unchanged.

[0032] Preferably, the specific process of step C2 is as follows:

[0033] D1. Wind and solar power are sent out and consumed in channels first. The hourly wind and solar power output process is determined according to the channel capacity limit and the hybrid pumped storage capacity. The part exceeding the channel capacity is stored through hybrid pumped storage. If there is surplus wind and solar power output after energy storage, it will be considered as abandoned wind and solar power output;

[0034] D2. The number of hybrid pumped-storage hydropower units should be determined by comprehensively considering the power efficiency;

[0035] D3. Iteratively calculate the hourly pumping flow rate according to the determined hourly pumping input process of the hybrid pumped storage; that is, assuming the pumping flow rate, calculate the increase in pumping head, pumping head, and unit pumping efficiency in each time period, update the pumping flow rate according to the pumping input, pumping head, unit pumping efficiency, etc., and iterate the process until the pumping flow rate converges and remains unchanged;

[0036] D4. According to the principle of water balance, the daily power generation water volume is determined according to the daily pumping water volume of the hybrid pumped storage;

[0037] D5. Calculate the water head of hybrid pumped storage power generation and determine the expected output;

[0038] D6. Similar to the iterative calculation of pumping input and pumping flow, the power generation output and power generation flow are determined through iterative calculation. That is, assuming the power generation flow, calculate the power generation head loss, power generation head, and unit power generation efficiency in each period, update the power generation flow according to the power generation output, power generation head, unit power generation efficiency, etc., and iterate the process until the power generation flow converges and remains unchanged;

[0039] D7. Calculate the storage capacity and water level of the upper reservoir and the lower reservoir at each time period based on the determined hourly process of the hybrid pumped storage flow and power generation flow;

[0040] D8, iterate the process D3, D4, D5, D6 and D7 until the pumping flow and power generation flow converge and remain unchanged.

[0041] Preferably, the algorithm calculation process of step S4 is as follows:

[0042] E1. Arrange the basic parameters of the reservoir power station, runoff data, and unit characteristic parameter input data;

[0043] E2. Based on the results of wind-solar complementarity of the upper reservoir and wind-solar complementarity of the hybrid pumped-storage system, calculate the inflow flow of the lower reservoir, analyze the changing pattern of the inflow flow, and clearly divide the water supply period and water storage period;

[0044] E3. Carry out the reverse regulation calculation of the lower reservoir power station every day, and find the optimal solution through trial calculation;

[0045] E4. According to the determined critical water level at the end of the water supply period, determine the storage capacity and water level change process of the lower reservoir in each period, and determine the power generation head loss, power generation head, generator set efficiency and power generation output of the lower reservoir power station according to the outflow flow;

[0046] E5. Combined with the daily complementary calculation of water, wind and solar power in the upper reservoir power station in step S2, the daily complementary calculation of wind and solar power in the hybrid pumped storage system in step S3, and the daily counter-regulation calculation of the lower reservoir in step S4, the storage capacity and water level status of the upper and lower reservoirs are finally determined. Therefore, it is necessary to repeat the large-loop iterative calculation of steps S2, S3, and S4 until the storage capacity and water level status of the upper and lower reservoirs remain unchanged and the nested results of the hydraulic calculation and power calculation of steps S2, S3, and S4 remain unchanged.

[0047] Preferably, the specific process of step E3 is as follows:

[0048] F1. Use binary search method to find the optimal solution of the critical water level at the end of the water supply period. The initial value is the average of the dead water level and the normal water level.

[0049] F2. The regulating storage capacity between the normal water level and the trial water level is both the available water volume for use during the water supply period and the required water volume for storage during the water storage period. This part of water volume is used to increase the flow during the period of low water supply period and to store water for replenishment during the period of high water supply period.

[0050] F3. Assuming the average outflow during the water supply period, count the time periods when the incoming water flow is less than the average outflow during the water supply period, calculate the total inflow of the corresponding period, add the total inflow water volume to the calculated available water volume during the water supply period, and divide it by the total number of time periods with less inflow to obtain the updated average outflow during the water supply period. This process needs to be iterated until the average outflow during the water supply period converges and remains unchanged, and the calculation result must meet the minimum outflow flow requirement;

[0051] F4. Assuming the average outflow during the water storage period, count the time periods when the incoming water flow during the water storage period is greater than the average outflow during the water storage period, calculate the total inflow water volume of the corresponding period, subtract the calculated water storage volume during the water storage period from the total incoming water volume, and divide it by the total number of time periods with more inflow to obtain the updated average outflow flow during the water storage period. This process needs to be iterated until the average outflow flow during the water storage period converges and remains unchanged, and the calculation result must meet the minimum outflow flow requirement;

[0052] F5. Determine the average outflow during the water supply period and the water storage period, and use the binary method to halve the range of judgment;

[0053] If the average outflow during the water supply period is less than that during the water storage period, it means that the available water volume during the water supply period is too small and more water can be stored during the water storage period. Therefore, the trial water level should be lowered and the solution range should be reduced to the lower half of the original solution range.

[0054] If the average outflow during the water supply period is greater than that during the water storage period, it indicates that the available water volume used during the water supply period is too large and the water storage should be reduced during the water storage period. Therefore, the trial water level should be raised and the solution range should be reduced to the upper half of the original solution range.

[0055] F6. Through repeated iterative processes F2, F3, F4 and F5, the solution range is continuously halved until the solution range approaches the optimal solution. The optimal solution at this time is the critical water level at the end of the water supply period, indicating that the binary search method gives a reasonable scheduling process for reservoir water supply and water storage under the current inflow conditions.

[0056] Preferably, the specific steps of step S5 are as follows:

[0057] G1. Determine the theoretical formula and calculation method of the model. The model is built using the basic equations of fluid mechanics, but needs to be modified for the unsteady flow under pumping simulation, including the continuity equation and momentum equation;

[0058] G2. Determine the model boundary conditions. In the hydraulic simulation of the lower reservoir pumping, boundary conditions need to be defined to describe the interaction between the fluid and the solid boundary, including fixed boundary conditions, free boundary conditions and inlet / outlet boundary conditions;

[0059] G3. Organize terrain data and collect surveying and mapping data of the entire reservoir. The surveying and mapping accuracy must meet the accuracy requirements for supporting hydrodynamic simulation, and organize the terrain data of the riverbed and reservoir bank;

[0060] G4. Perform grid division, determine the grid size, generate a two-dimensional grid of the water body, and represent the horizontal and vertical distribution of water flow by dividing the water body into small grid cells;

[0061] The non-uniform grid division method is adopted to appropriately increase the area of ​​a single grid in relatively unimportant areas, and to encrypt the grids of important local river sections near the inlet / outlet, which can coordinate the relationship between grid density, calculation time and calculation accuracy.

[0062] G5. Determine the calculation step size, select different simulation time steps to simulate the same terrain, keep other boundary conditions unchanged, and analyze the sensitivity of the simulation results;

[0063] In the hydrodynamic simulation of pumping conditions, a segmented simulation strategy is adopted, and different time steps are selected according to different pumping reliability to ensure the accuracy of simulation results at critical moments;

[0064] G6. Calibrate the riverbed roughness. Calibrate the riverbed roughness of the hydrodynamic model based on the relationship between the measured flow and the corresponding water surface line.

[0065] Considering that the gradient, riverbed composition and cross-sectional geometry of long-distance rivers may vary greatly, in order to ensure that the calibration results can more accurately reflect the real river terrain characteristics, the riverbed roughness is set in sections according to the above factors. At the same time, the calibration efficiency can be improved by adopting the method of section-by-section calibration.

[0066] G7,Model rationality analysis,The first step is to judge the reliability of the simulation results under different initial conditions according to the hydrodynamic laws;

[0067] In the second step, the measured data are used to analyze the accuracy of the simulation results, and the correlation coefficient and Nash coefficient are used to judge the accuracy of the simulated water level process and the measured process. If the correlation coefficient or Nash coefficient is greater than 0.8 and the p-value is <0.05, it can be considered that the results simulated by this model have a high degree of credibility.

[0068] G8. Develop simulation conditions and perform hydrodynamic simulation calculations. Combine the daily calculation results after iterative convergence of step S2, step S3, and step S4, summarize and classify different pumping conditions and power generation conditions. The conditions can be sorted out to reach hundreds or thousands, and a large number of hydrodynamic numerical simulations of pumping conditions and power generation conditions can be performed.

[0069] For each working condition, it is necessary to set the initial water level and flow boundary conditions of the lower reservoir, make the boundary conditions of all working conditions as input data, and apply the lower reservoir hydrodynamic numerical simulation model to carry out numerical simulation calculations.

[0070] Preferably, the specific steps of step S6 are as follows:

[0071] H1. Use high-performance computers to obtain simulation results of all calculation conditions and process simulation output data in batches for summary and analysis of hydrodynamic laws;

[0072] H2. Using big data analysis, the hydrodynamic simulation results of all calculation conditions are summarized and statistically analyzed to obtain three sets of water level-discharge relationship curves;

[0073] The first is the relationship curve between the water level of the hybrid pumped storage inlet / outlet, the storage capacity of the lower reservoir, the hybrid pumped storage / power generation flow, and the outflow flow of the upper reservoir power station;

[0074] The second is the relationship curve among the tailwater level of the upper reservoir, the outflow of the upper reservoir, the storage capacity of the lower reservoir, and the hybrid pumped storage / power generation flow;

[0075] The third is the relationship curve among the water level in front of the lower reservoir dam, the storage capacity of the lower reservoir, the outflow of the lower reservoir, and the hybrid pumped storage / power generation flow;

[0076] H3. Convert the rules summarized in the above hydrodynamic simulation into the water level-flow relationship curve after big data analysis, and then convert them into the input conditions for hydraulic calculation. Feedback the hydrodynamic rules into the daily complementary calculation of water, wind and solar power in the upper reservoir power station in step S2, the daily complementary calculation of wind, solar and storage in the hybrid pumped storage in step S3, and the daily reverse regulation calculation step of the lower reservoir in step S4, to ensure the rationality and accuracy of the joint operation scheduling plan.

[0077] The present invention provides a hybrid pumped-storage joint operation scheduling method coupled with pumped-water power generation hydrodynamic simulation, with the following beneficial effects:

[0078] 1. The invention proposes the concept of a "2 reservoirs and 3 stations" joint operation and dispatching system, that is, the hybrid pumped storage and its upper reservoir, lower reservoir, upper reservoir hydropower station, and lower reservoir power station together constitute a "2 reservoirs and 3 stations" joint system, realizing the superposition and combination of water-wind-solar integration and wind-solar-storage integration, as well as the nesting of hydraulic calculations of cascade reservoirs and complementary power calculations of water-wind-solar-storage;

[0079] 2. The present invention adopts the method of coupled hydrodynamic simulation to correct the rationality and accuracy of operation scheduling;

[0080] 3. The present invention proposes a water-wind-solar integrated complementary operation scheduling strategy for the upper reservoir power station, which realizes the embedding of hydraulic calculation into the electric power complementary calculation of the upper reservoir power station;

[0081] 4. The present invention proposes a water-wind-solar integrated complementary operation scheduling strategy for the upper reservoir power station, which realizes the embedding of hydraulic calculation into the electric power complementary calculation of the upper reservoir power station;

[0082] 5. The present invention proposes a hybrid pumped-storage, wind-solar-solar integrated lower reservoir counter-regulation scheduling strategy. BRIEF DESCRIPTION OF THE DRAWINGS

[0083] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0084] Figure 1 It is a flow chart of the present invention;

[0085] Figure 2 It is a specific technical roadmap of the method of the present invention; DETAILED DESCRIPTION

[0086] Example 1

[0087] like Figures 1-2 As shown in FIG. 1 , a hybrid pumped-storage joint operation scheduling method coupled with pumped-hydropower generation hydrodynamic simulation is shown in FIG. 1 , and the method steps are as follows:

[0088] Step S1: Determine the boundary conditions for joint operation scheduling, as follows:

[0089] The first category is the basic parameters of reservoir power stations and hybrid pumped storage. The basic parameters include normal water storage level, dead water level, installed capacity, single unit capacity, rated head, base load output, full generation flow, minimum discharge flow, power generation head loss, pumping head loss, and delivery channel scale.

[0090] The second category is the characteristic curves of reservoir power stations and hybrid pumped storage. The characteristic curves include water level and storage capacity relationship curves, reservoir operation and dispatch limit lines, unit maintenance arrangement curves, tailwater level and flow relationship curves, inlet / outlet water level and flow relationship curves, etc.

[0091] The third category is representative hydrological series data. You can choose three or five representative years, 365-day daily runoff series of the upper reservoir, and the interval runoff series between the upper and lower reservoirs.

[0092] The fourth category is representative new energy data, including reservoir power stations, hybrid pumped storage complementary new energy scale, and the corresponding hourly 8760h typical output process.

[0093] The fifth category is the unit operation characteristic curves of reservoir power stations and hybrid pumped storage. Generally, many groups of two-dimensional plane curves are used to represent the unit operation efficiency under different head and flow conditions. In order to facilitate the calculation and query of unit operation efficiency, a three-dimensional discretization method is adopted, similar to the way of converting contour lines into rasterized digital elevations. Many groups of two-dimensional efficiency curves are organized into three-dimensional space and discretized into grid points. The grid coordinates represent different heads and different flows, and the grid values ​​represent the corresponding unit operation efficiency, and finally a two-dimensional array of unit operation efficiency is formed.

[0094] Step S2: Establishing the integrated operation and dispatching model of the upper reservoir water, wind and solar

[0095] The complementary operation of the upper reservoir power station and wind power and photovoltaic power generation is based on the following dispatching principles:

[0096] (1) Annual operation and dispatch. Based on the annual runoff regulation calculation of the reservoir power station, equal flow generation is adopted in the flood season and equal output generation is adopted in the dry season to determine the annual scale of power generation water allocation, average output and reservoir drawdown process. The complementary operation of the upper reservoir power station and wind and solar power does not change the annual scale of operation and dispatch process.

[0097] (2) Monthly operation and dispatching. On a monthly scale, the hydropower output process and water volume distribution on each day of the month can be slightly adjusted according to the characteristics of the complementary wind and solar power output of the upper reservoir power station, so that the combined output of water, wind and solar power after complementation is more stable and uniform.

[0098] (3) Constraints on the water volume, water level and flow of the upper reservoir. Constraints such as water volume balance, water level operation range restrictions (dead water level ~ normal water storage level, or dead water level ~ flood limit water level), and minimum downstream flow requirements should be met.

[0099] Water balance constraints:

[0100] V up (t+1)=V up (t)+(Q upin (t)-Q upout (t)+Q p (t))*dt(Formula 2-1)

[0101] Where V up (t+1) is the water storage capacity of the upper reservoir in the next period, V up (t) is the water storage capacity of the upper reservoir in the current period, Q upin (t) is the inflow of the upper reservoir in the current period, Q upout (t) is the outflow of the upper reservoir in the current period, Q p (t) is the pumping flow rate in the current period, and dt is the time interval of the calculation period.

[0102] Reservoir water level constraints:

[0103] Z upmin ≤Z up (t)≤Z upmax (Formula 2-2)

[0104] In the formula, Z up (t) is the water level of the upper reservoir in the current period, Z upmin is the lowest operating water level of the upper reservoir (the lowest can reach dead water level), Z upmax It is the highest operating water level of the upper reservoir (the highest water level before the flood season can reach the flood limit water level, and the highest water level at the end of the flood season can reach the normal water storage level).

[0105] Ecological and unit minimum downstream flow constraints:

[0106] Q upout (t)≥max(Q upenv ,Q upmin )(Formula 2-3)

[0107] In the formula, Q upout (t) is the outflow of the upper reservoir in the current period, Q upenv is the ecological flow that should be guaranteed by the upper reservoir, Qupmin It is the minimum downstream flow required for the upper reservoir unit to generate electricity.

[0108] (4) Power generation constraints of the upper reservoir power station. The power generation conditions of the upper reservoir power station take into account the minimum power generation output limit of a single unit, excluding the maintenance units, and consider the unit capacity is blocked when the water level of the upper reservoir is low and the power generation head is lower than the rated head of the turbine, that is, to meet the expected output requirements under different heads.

[0109]

[0110] Where N up (t) is the power generation output of the upper reservoir in the current period, n up (t) is the number of units in operation during the current period (excluding units under maintenance), N upmin is the minimum power output of a single machine, N upmax (t) is the maximum generating capacity of the unit under the corresponding water head of the upper reservoir in the current period. up (t) is the generating head of the upper reservoir power station in the current period, H uprate is the rated water head of the upper reservoir unit, N upunit is the capacity of the upper reservoir unit. When the water head is not lower than the rated water head, there is no obstruction. When the water head is lower than the rated water head, it is necessary to calculate the maximum power generation capacity after considering the obstruction. g is the acceleration of gravity, Q up (t) is the power generation flow of the upper reservoir power station in the current period (when the power generation head is lower than the rated head, the maximum power generation flow is lower than the rated power generation flow), η up1 (t) is the turbine efficiency of the upper reservoir, η up2 For the efficiency of the generator on the reservoir.

[0111] (5) Calculation of the generating efficiency of the upper reservoir power station unit. The efficiency of the turbine unit of the upper reservoir power station is obtained according to the operating characteristic curve. Specifically, the two-dimensional array of the unit operating efficiency formed by three-dimensional discretization can be queried.

[0112]

[0113] (6) Nested calculation of hydropower and electricity. Ensure the nesting of hydropower calculation and electricity calculation in accordance with the idea of ​​"determining the hydropower output based on the complementary wind and solar power, and determining the hydropower output based on the hydropower inflow". According to the output characteristics of new energy and the demand for complementarity, adjust the daily output process and flow distribution of the hydropower station, reduce the power generation flow and output during the day, free up channels for wind and solar power transmission, and adjust the power generation flow and output appropriately in the early morning to make up for the reduced power generation during the day.

[0114] (7) Processing of hybrid pumped-storage power generation. If the hybrid pumped-storage unit cannot generate electricity but can pump water during certain periods of time (unit maintenance, or low head causing unit power generation to be restricted), and the water pumped to the upper reservoir cannot be discharged through the hybrid pumped-storage unit, it is necessary to use the surplus capacity of the upper reservoir power station unit to generate electricity. The upper reservoir power station unit should be used in the operation and scheduling of the upper reservoir power station to realize this part of the hybrid pumped-storage power generation.

[0115] (8) Power generation statistics of the Upper Reservoir Power Station. The power generation output is reasonably calculated based on the hourly power generation head, power generation efficiency, and power generation flow. Based on the hourly power generation output process, the annual power generation and annual power generation utilization hours of the Upper Reservoir Power Station can be calculated.

[0116]

[0117] In the formula, E up is the annual power generation of the upper reservoir power station, and dt is the calculation time interval. up is the annual power generation utilization hours of the upper reservoir power station, N upcapacity This is the installed capacity of the upper reservoir power station.

[0118] (9) Statistics on complementary wind and solar power generation at the upper reservoir power station. The bundled output should not exceed the channel capacity limit of the upper reservoir power station (wind and solar can be sent out using the surplus space in the channel when the hydropower station is blocked or under maintenance). When the complementary output of wind and solar exceeds the channel capacity, wind and solar are abandoned in the same proportion, thereby determining the hourly wind and solar output process, annual power consumption, and wind and solar abandonment rates.

[0119] N up (t)+N upFG (t)≤N upchannel (Formula 2-8)

[0120] N upabandon (t) = N upgenerate (t)-N upFG (t) (Formula 2-9)

[0121] Where N up (t) is the power generation output of the upper reservoir in the current period, N upFG (t) is the wind power and photovoltaic power output that complements the hydropower of the reservoir in the current period, N upchannel is the maximum capacity of the transmission channel of the upper reservoir. N upgenerate (t) is the available power output of wind power and photovoltaic power generation in the reservoir at the current time period, N upabandon (t) is the abandoned wind and solar power output of the complementary wind and photovoltaic power generation in the reservoir during the current period.

[0122]

[0123] In the formula, E upFGis the annual consumption of wind and solar power complementary to the upper reservoir power station, dt is the calculation time interval, h upFG is the annual power generation utilization hours of the upper reservoir power station complementing wind and solar power, N upFGcapacity It is to complement the installed capacity of wind and solar power stations in the upper reservoir. upabandon The amount of wind and solar power abandoned by the upper reservoir power station, R upFG The wind and solar power abandonment rate that complements the upper reservoir power station.

[0124] Step 3: Establish a hybrid pumped storage wind and solar storage integrated operation and dispatching model

[0125] The complementary operation of hybrid pumped storage, wind power and photovoltaic power includes the following dispatching principles:

[0126] (1) Nested calculation of water power and electricity. The nesting of water power calculation and electricity calculation is ensured by following the idea of ​​"determining the pumping input and pumping flow rate based on complementary wind and solar power, and determining the power generation flow rate and power generation output based on the pumping flow rate". According to the output characteristics of new energy and the complementary needs, the pumping and power generation periods within the day are reasonably arranged. When the wind and solar power output is large during the day, the surplus wind and solar power output is pumped and stored, and the peak power generation is operated during the evening peak. In the early morning, the power generation is supplemented according to the pumping volume. It is carried out in two steps. The first step is to determine the time period and pumping output required for pumping in combination with the pumping characteristics of the unit and the power transmission channel, and determine the pumping flow rate accordingly. The second step is to convert the pumped water into power generation water according to the water balance principle, and reasonably allocate the power generation output and flow rate within the day.

[0127] (2) Calculation of pumping head and generating head of hybrid pumped storage. The head amplitude of hybrid pumped storage changes with the water storage and drawdown of the upper reservoir. The annual change process of the upper reservoir is related to different water inflow conditions, the dispatching and operation of the reservoir and power station. In addition, the head amplitude of hybrid pumped storage is also related to the daily water level drawdown of the lower reservoir and the water level-flow relationship curve of the lower reservoir inlet / outlet. The larger the outflow of the upper reservoir power station, the more likely it is to cause the water level near the lower reservoir inlet / outlet to rise.

[0128] H g (t) = Z up (t)-Z down (t)-H gloss (Q g (t))(Formula 3-1)

[0129]

[0130] In the formula, H g (t) is the hybrid pumped storage power generation head in the current period, Z up (t) is the water level in front of the reservoir dam in the current period, Z down (t) is the water level near the reservoir inlet / outlet in the current period, H glossis the head loss of the hybrid pumped storage power generation, and the hybrid pumped storage power generation flow Q in the current period g (t) related. g (t) is the hybrid pumped storage power generation output in the current period, η1(t) is the efficiency of the hybrid pumped storage turbine, and η2 is the efficiency of the hybrid pumped storage generator. The two formulas are nested and require appropriate iterative calculations in practical applications.

[0131] H p (t) = Z up (t)-Z down (t)+H ploss (Q p (t))(Formula 3-3)

[0132]

[0133] In the formula, H p (t) is the pumping head of the hybrid pumped storage in the current period, H ploss is the added value of the hybrid pumped storage pumping head, and is related to the hybrid pumped storage pumping flow Q in the current period p (t) related. p (t) is the hybrid pumped storage pumping input in the current period, η3(t) is the hybrid pumped storage pump efficiency, and η4 is the hybrid pumped storage motor efficiency. The two formulas are nested and require appropriate iterative calculations in practical applications.

[0134] Z down (t) = f(V down (t),Q g (t)|Q p (t),Q upout (t))(Formula 3-5)

[0135] Where, the water level Z near the inlet / outlet of the lower reservoir is down (t), mainly related to the reservoir capacity V in the current period down (t). It is also affected by the continuous pumping flow Q of the hybrid pumped storage system. p (t) or power generation flow Q g The influence of (t) cannot be directly determined by looking up the water level and storage capacity relationship curve, but needs to be determined through hydrodynamic correction and repeated iterative calculation. In addition, the outflow of the upper reservoir in the current period Q upout The high water level caused by (t) may also affect the water level near the inlet / outlet of the lower reservoir.

[0136] (3) Calculation of pumping input of hybrid pumped storage units. The hybrid pumped storage pump operating conditions consider the pumping of an integer number of units, excluding the units under maintenance. When pumping, the water levels at the inlet / outlet of the upper and lower reservoirs need to be no lower than the pumping limit water level, and the limitation of the remaining regulating storage capacity of the lower reservoir should be considered. When the water level of the upper reservoir is low and the water level of the lower reservoir is high, the pumping head is small and the pumping flow is large, and the pumping input is slightly greater than the capacity of a single unit; when the water level of the upper reservoir is high and the water level of the lower reservoir is low, the pumping head is large and the pumping flow is small, and the pumping input is slightly less than the capacity of a single unit.

[0137]

[0138] N p (t) = n p (t)N unit R p (H p (t))(Formula 3-7)

[0139] In the formula, Z downmin To limit the water level for the lower reservoir pumping operation, is the normal water level of the lower reservoir, N p (t) is the hybrid pumped storage input in the current period, which is based on the pumping of an integer number of units, n p (t) is the number of hybrid pumped storage units in operation during the current period (excluding units under maintenance), N unit is the unit capacity of the hybrid pumped storage unit, R p is the pumping power coefficient of the hybrid pumped storage unit, and the pumping head H of the hybrid pumped storage unit in the current period p (t) is related to the lift. When the lift is small, it is generally greater than 1, and when the lift is large, it is generally less than 1.

[0140] (4) Calculation of unit power generation output of hybrid pumped storage. The hybrid pumped storage turbine operating conditions take into account the minimum power generation output limit of a single unit, deduct the maintenance unit, and consider the unit capacity is blocked when the upper reservoir water level is low and the generating head is lower than the rated head of the turbine.

[0141]

[0142] Where N g (t) is the hybrid pumped storage power generation output in the current period, n g (t) is the number of hybrid pumped storage generator sets in operation during the current period (excluding the units under maintenance), N gmin is the minimum power generation output of a single hybrid pumped storage unit, N gmin (t) is the maximum generating capacity of the hybrid pumped storage unit under the corresponding water head in the current period. g (t) is the hybrid pumped storage power generation head in the current period, H grate is the rated water head of the hybrid pumped storage unit, Ngunit is the capacity of a single unit of a hybrid pumped storage unit, and is unobstructed when the water head is not lower than the rated water head. When the water head is lower than the rated water head, it is necessary to calculate the maximum power generation capacity after considering the obstruction, η1(t) is the efficiency of the hybrid pumped storage turbine, and η2 is the efficiency of the hybrid pumped storage generator.

[0143] (5) Calculation of unit efficiency of hybrid pumped storage. The unit efficiency of the actual pumping and power generation of the hybrid pumped storage can be obtained based on the operating characteristic curve. Specifically, the two-dimensional array of unit operating efficiency formed by three-dimensional discretization can be queried.

[0144]

[0145] η3(t)=f(H o (t))(Formula 3-11)

[0146] (6) Treatment of additional power generation at the upper reservoir power station. In a flood year with more natural runoff, the water inflow to the upper reservoir is relatively abundant during the flood season. At this time, the conventional units of the upper reservoir power station have already generated full power, but a small amount of water may still be abandoned. The excess water can be generated by the reversible units of the hybrid pumped storage to increase the power generation output and realize the resource utilization of conventional hydropower abandonment. The reversible units of the hybrid pumped storage should be used in the operation and scheduling of the hybrid pumped storage to realize this part of the additional power generation of the upper reservoir power station.

[0147] (7) Hybrid pumped storage power generation and pumping statistics. Reasonably calculate the pumping and power generation output based on the hourly head, efficiency, and flow. Calculate the pumped power and annual power generation of the hybrid pumped storage based on the hourly pumping input and power generation process, and determine the pumped power generation cycle efficiency of the hybrid pumped storage.

[0148]

[0149] In the formula, E g is the annual power generation of hybrid pumped storage, h g is the annual power generation utilization hours of hybrid pumped storage, E p is the annual pumped hydroelectricity of the hybrid pumped storage system, h p is the annual pumping hours of hybrid pumped storage, N capacity Hybrid pumped storage installed capacity, dt is the calculation time interval, η cycle is the annual power generation pumping cycle efficiency of the hybrid pumped storage.

[0150] (8) Statistics of hybrid pumped-storage and wind-solar power generation. The bundled output should not exceed the channel capacity limit of the hybrid pumped-storage system (wind and solar can use the excess channel space when the hybrid pumped-storage power station is blocked or under maintenance). When the wind and solar output still exceeds the channel capacity after deducting the pumped-storage input, wind and solar are abandoned in the same proportion, and the wind and solar abandonment rates are calculated.

[0151] Ng (t)+N FG (t)≤N channel (Formula 3-15)

[0152] N abandon (t) = N generate (t)-N p (t)-N FG (t) (Formula 3-16)

[0153] Where N g (t) is the power generation output of the hybrid pumped storage in the current period, N FG (t) is the wind power and photovoltaic output that complements the hybrid pumped storage in the current period, N channel is the maximum capacity of the hybrid pumped storage transmission channel. N generate (t) is the power output of the hybrid pumped storage and wind power photovoltaic system in the current period, N abandon (t) is the abandoned wind and solar power output of the hybrid pumped storage complementary wind power and photovoltaic power generation in the current period, N p (t) is the pumping input of hybrid pumped storage in the current period.

[0154]

[0155] In the formula, E FG is the annual power consumption of the hybrid pumped storage power station complementing wind and solar power, dt is the calculation time interval, h FG is the annual power generation utilization hours of the hybrid pumped storage system complementing wind and solar power, N FGcapacity The installed capacity of hybrid pumped storage and wind-solar complementary power generation. abandon is the amount of wind and solar power abandoned by the hybrid pumped storage system, R FG is the wind and solar curtailment rate of hybrid pumped storage and wind-solar complementary system, E p It is the annual pumped hydroelectricity of hybrid pumped storage.

[0156] Step 4: Establish the counter-regulation operation and dispatching model of the lower reservoir

[0157] If the regulating capacity of the lower reservoir is large and has the conditions for complementary operation with wind power and photovoltaic power, it can be similar to the upper reservoir, and its scheduling principles are the same as those of the upper reservoir.

[0158] If the regulating storage capacity of the lower reservoir is small and does not have the ability to complement wind power and photovoltaic power, the lower reservoir power station will take priority in undertaking the daily counter-regulation task of the upper reservoir power station and the hybrid pumped storage power station. The dispatching principles for counter-regulation operation are as follows:

[0159] (1) Determination of the inflow flow of the lower reservoir power station. The inflow flow of the lower reservoir should take into account the outflow flow of the upper reservoir power station, possible interval inflow flow, superimposed hybrid pumped storage power generation flow, and deduct the pumping flow of the hybrid pumped storage.

[0160] Q downin (t) = Q upout (t)+Q interval (t)+Q g (t)-Q p (t)(Formula 4-1)

[0161] In the formula, Q downin (t) is the water flow of the lower reservoir in the current period, Q upout (t) is the outflow of the upper reservoir in the current period, Q interval (t) is the inflow flow between the upper and lower reservoirs in the current period, Q g (t) is the power generation flow of the hybrid pumped storage in the current period, Q P (t) is the pumping flow of hybrid pumped storage in the current period.

[0162] (2) Constraints on the amount of water, water level and flow in the lower reservoir. Constraints such as water balance, water level operation range restrictions (dead water level to normal water storage level, or dead water level to flood limit water level), and minimum discharge flow requirements should be met.

[0163] Water balance constraints:

[0164] V down (t+1)=V down (t)+(Q downin (t)-Q downout (t))*dt(Formula 4-2)

[0165] Where V down (t+1) is the water storage capacity of the lower reservoir in the next period, V down (t) is the water storage capacity of the lower reservoir in the current period, Q downin (t) is the water flow of the lower reservoir in the current period, Q downout (t) is the outflow of the lower reservoir in the current period, and dt is the time interval of the calculation period.

[0166] Reservoir water level constraints (inlet / outlet water level, dam front water level):

[0167] Z downmin ≤Z down (t)≤Z downmax (Formula 4-3)

[0168] Z′ downmin ≤Z′ down (t)≤Z downmax (Formula 4-4)

[0169] In the formula, Z down (t) is the water level of the lower reservoir inlet / outlet in the current period, Z downminThe water level limit for pumping operation at the inlet / outlet of the lower reservoir (may be lower than the dead water level when there is a pumping funnel effect), Z downmax It is the highest water level of the lower reservoir (up to the normal water level). Z′ down (t) is the water level in front of the lower reservoir dam in the current period, Z′ downmin The lowest water level in front of the lower reservoir dam (usually dead water level)

[0170] Ecological and unit minimum downstream flow constraints:

[0171] Q downout (t)≥Q min =max(Q downenv ,Q downmin )(Formula 4-5)

[0172] In the formula, Q down (t) is the outflow of the lower reservoir in the current period, Q min is the minimum outflow of the lower reservoir, and the ecological flow Q that the lower reservoir should ensure downenv The minimum discharge flow Q required for the Hexia Reservoir unit to generate electricity downmin The larger value of .

[0173] (3) Analyze the operation and dispatch characteristics of each time period during the day and determine the division of counter-regulation operation time periods.

[0174] The day can be divided into three time periods (daytime photovoltaic power generation period, evening load peak period, and other time periods in the early morning). Considering the requirements of the reservoir counter-regulation task, the requirements of ecological flow stability, and the requirements of downstream river habitat stability, the requirements of counter-regulation scheduling are determined as "maintaining flow stability as much as possible in each time period and minimizing flow differences between time periods". Based on this requirement, the specific operation and scheduling methods for each time period are determined as follows:

[0175] During the daytime when photovoltaic power generation is high (e.g. 10:00-18:00): the reservoir is initially maintained at a normal water level as much as possible to ensure sufficient water. On the basis of retaining the storage capacity required for the ecological flow discharged from the lower reservoir power station, the water volume required for hybrid pumping and storage is met, and the remaining water volume is discharged reasonably and stably. When the output of new energy is large, the hybrid pumping and storage pumps more water. If there is still remaining storage capacity, the discharge flow of the lower reservoir power station can be increased; when the output of new energy is small, the hybrid pumping and storage pumps less water, and there is more remaining storage capacity. It is appropriate to draw more water during the flood season and discharge appropriately during the dry season. In this case, the lower reservoir does not necessarily draw down to the dead water level at the end of the day and before the evening peak.

[0176] During the evening peak period (e.g. 19:00-24:00): meet the peak-shaving needs of the power grid, and store the remaining water reasonably. If the peak-shaving demand of the power grid is high, the lower reservoir power station and the upper reservoir power station will perform peak-shaving synchronously, the power generation output will be large, and the amount of water available for water storage in the reservoir will be small. Choose appropriate water storage. If the peak-shaving demand of the power grid is relatively small, the power generation output of the lower reservoir power station is small, the power generation flow is reduced, and the amount of water that can be stored in the reservoir is large. At this time, it is appropriate to store water during the evening peak of the dry season to ensure that it can be stored to the normal water storage level during the daytime of the next day; it is not necessary to store water to the normal water storage level at the end of the evening peak of the flood season. It is advisable to coordinate with the water inflow situation in the early morning period, reasonably control the water storage rhythm, and ensure that it can be stored to the normal water storage level during the daytime of the next day.

[0177] Other periods in the early morning (for example, 0:00-9:00): Electricity consumption is low, photovoltaic power generation does not occur, and water is stored appropriately according to the inflow flow to ensure that there is sufficient water in the reservoir before the lunch rush hour.

[0178] When calculating the intraday counter-regulation, the reservoir water storage and release conditions are taken into consideration. The daytime photovoltaic peak period can be regarded as the water supply period, and the evening peak period and other periods in the early morning can be regarded as the water storage period. The changing pattern of the incoming water flow can be analyzed to divide the water supply period and the water storage period. That is, the period when the incoming water flow increases and decreases can be used as the dividing period when the water storage period ends and the water supply period begins, and the period when the incoming water flow decreases and increases can be used as the dividing period when the water supply period ends and the water storage period begins, thereby clearly dividing the water supply period and the water storage period.

[0179] (4) Daily counter-regulation operation and dispatching strategy of the lower reservoir.

[0180] According to the idea of ​​"rationally dividing the water storage and supply periods, making full use of the regulating storage capacity of the lower reservoir to smooth the outflow flow, and minimizing the daily outflow flow fluctuation", the use of the counter-regulation storage capacity and water level scheduling of the lower reservoir are determined.

[0181] According to the principle of counter-regulation of the lower reservoir, the flow rate during the water supply period and the water storage period should be kept as stable as possible, and the fluctuation (difference) of the outflow flow between the water supply period and the water storage period should be as small as possible. The optimization objective function is as follows:

[0182]

[0183] Where ΔQ represents the difference in average outflow between the water supply period and the water storage period. represents the average outflow during the water supply period, represents the average outflow during the water storage period. Both variables are related to the critical water level Z of the lower reservoir at the end of the water supply period and the beginning of the water storage period (i.e., the end of the day and the beginning of the evening peak). critical related.

[0184] Determine the critical water level Z of the lower reservoir at the end of the water supply period and the beginning of the water storage period (i.e. the end of the day and the beginning of the evening peak) by trial calculation critical , determining this water level can determine the water supply volume V of the lower reservoir during the water supply period gong , water storage capacity of the lower reservoir during the water storage period V xu .

[0185]

[0186] In the formula, represents the storage capacity corresponding to the normal water level of the lower reservoir, V(Z critical ) represents the storage capacity corresponding to the critical water level of the reservoir at the end of the water supply period and the beginning of the water storage period.

[0187] (5) Determine the reservoir operation and outflow process during the water supply period and water storage period.

[0188] During the water supply period, the water supply of the lower reservoir V should be fully utilized. gong , minimize the outflow during the water supply period, that is, use the regulating reservoir capacity to increase the outflow to Iterative calculations are required for specific calculations. With V gong Directly related, the calculation formula is as follows:

[0189]

[0190] In the formula, Q min represents the minimum outflow of the lower reservoir, dt represents the calculation time interval, T represents the total number of periods when the water inflow is low and the regulating storage capacity needs to be used for replenishment, ΔQ gong (t) represents the outflow flow that can be provided by the water during the period when the regulating reservoir capacity needs to be used for replenishment. downin (t) After deducting the minimum outflow, it is still less than the average outflow during the water supply period Statistics are taken at the time.

[0191] During the water storage period, it is necessary to ensure that the lower reservoir completes the water storage capacity V xu , while completing the water storage task, reduce the outflow during the water storage period, that is, reasonably store water during the period with more water, and reduce the outflow to Iterative calculations are required for specific calculations. With V xu Directly related, the calculation formula is as follows:

[0192]

[0193] In the formula, Q min represents the minimum outflow of the lower reservoir, dt represents the calculation time interval, T represents the total number of time periods when there is more water and water can be stored, ΔQxu (t) represents the outflow flow rate that can be provided by the incoming water during the period of water storage. downin (t) After deducting the minimum outflow, it is greater than the average outflow during the storage period Statistics are taken at the time.

[0194] (6) Power generation constraints of the lower reservoir power station. The power generation conditions of the lower reservoir power station take into account the minimum power generation output limit of a single unit, excluding the maintenance units, and consider the unit capacity is blocked when the water level of the lower reservoir is low and the power generation head is lower than the rated head of the turbine, that is, to meet the expected output requirements under different water heads.

[0195]

[0196] Where N down (t) is the power generation output of the lower reservoir in the current period, n down (t) is the number of units in operation during the current period (excluding units under maintenance), N downmin is the minimum power output of a single machine, N downmax (t) is the maximum generating capacity of the unit under the corresponding water head of the lower reservoir in the current period. down (t) is the generating head of the reservoir power station in the current period, H downrate is the rated water head of the lower reservoir unit, N downunit is the unit capacity of the lower reservoir unit. It is unobstructed when the water head is not lower than the rated water head. When the water head is lower than the rated water head, it is necessary to calculate the maximum power generation capacity after obstruction, Q down (t) is the power generation flow of the reservoir power station in the current period (when the power generation head is lower than the rated head, the maximum power generation flow is lower than the rated power generation flow), η dn1 (t) is the turbine efficiency of the lower reservoir, η dn2 The efficiency of the generator under the reservoir.

[0197] (7) Calculation of the generating efficiency of the lower reservoir power station. The generating efficiency of the lower reservoir power station is obtained based on the operating characteristic curve. Specifically, the two-dimensional array of the generating efficiency formed by three-dimensional discretization can be queried.

[0198]

[0199] (8) Power generation statistics of the lower reservoir power station. Reasonably calculate the power generation output based on the hourly power generation head, power generation efficiency, and power generation flow. Determine the annual power generation and annual power generation hours of the lower reservoir power station based on the hourly power generation process.

[0200]

[0201] In the formula, E down is the annual power generation of the lower reservoir power station, and dt is the calculation time interval. downis the annual power generation utilization hours of the lower reservoir power station, N downcapacity This is the installed capacity of the lower reservoir power station.

[0202] Step 5: Establish a numerical simulation model for the coupling of pumping power generation and hydrodynamics of the lower reservoir

[0203] The theoretical basis of hydrodynamic simulation involves continuity equations and momentum equations, basic equations of fluid mechanics, boundary conditions and initial conditions, and numerical calculation methods. The upper reservoir generally has a large regulating storage capacity, and pumping and power generation have little impact on the upper reservoir. The inlet / outlet of the lower reservoir is generally located at the tail of the lower reservoir, and is greatly affected by the pumping and power generation flow. Therefore, the main focus is on establishing a numerical simulation model of the lower reservoir pumping and power generation coupled hydrodynamics.

[0204] (1) Determine the theoretical formula and calculation method of the model. The model is built using the basic equations of fluid mechanics, but needs to be modified for the unsteady flow under pumping simulation, including the continuity equation (mass conservation equation), momentum equation, etc. The following is the two-dimensional Saint-Venant equations for unsteady flow:

[0205] h=Hz (Formula 5-1)

[0206] Where h is the water depth; H is the water level elevation; and Z is the riverbed elevation.

[0207] Considering that pumping simulation is a non-steady flow, its source and sink terms are not equal to 0, and its continuity equation is:

[0208]

[0209] Where x and y are distance coordinates in the Cartesian rectangular coordinate system; t is the time coordinate; u and v are the flow velocities in the x and y directions respectively; and q is the source-sink vector.

[0210] Similarly, its momentum equation is expressed as follows:

[0211]

[0212] Where g is the acceleration due to gravity; v is t is the turbulent viscosity coefficient; c f is the bottom friction coefficient; f is the Coriolis coefficient.

[0213] The model uses numerical calculation methods such as finite difference method, finite element method, finite volume method, etc. to solve the basic equations, and finally obtains parameters such as fluid velocity and pressure on different grids through numerical iterative calculation.

[0214] (2) Determine the model boundary conditions. In the hydrodynamic simulation of reservoir pumping, boundary conditions need to be defined to describe the interaction between the fluid and the solid boundary, including fixed boundary conditions (such as solid wall, wall friction), free boundary conditions (such as free water surface) and inlet / outlet boundary conditions.

[0215] The model uses the initial water level elevation as the water level at the initial moment of hydrodynamic calculation and defines three water inlet / outlet boundaries of the lower reservoir: the outflow of the upper reservoir power station in, the outflow of the lower reservoir power station out, and the outflow of the pumped flow of the hybrid pumped storage or the inflow of the power generation flow.

[0216] (3) Organize terrain data. Collect surveying and mapping data of the entire reservoir. The surveying and mapping accuracy must meet the accuracy requirements for supporting hydrodynamic simulation, and organize the terrain data of the riverbed and reservoir bank. If necessary, discrete interpolation can be used to generate raster terrain data with a resolution of 1m×1m.

[0217] (4) Perform grid division and determine the grid size. Generate a two-dimensional grid of the water body. By dividing the water body into small grid units, the horizontal and vertical distribution of the water flow can be represented. The resolution and accuracy of the grid can be adjusted as needed, taking into account both the calculation accuracy and the calculation time. When modeling terrain, the denser the grid division, the higher the calculation accuracy, but the single calculation time increases exponentially.

[0218] By adopting a non-uniform grid division method, the area of ​​a single grid is appropriately increased in relatively unimportant areas, and the grid is encrypted in important local river sections near the inlet / outlet, which can coordinate the relationship between grid density, calculation time and calculation accuracy.

[0219] (5) Determine the calculation step size. The calculation time step size will affect the calculation accuracy of the hydrodynamic simulation of the reservoir pumping and power generation. In order to evaluate the sensitivity of the simulation results to the change of the time step size, different simulation time steps can be selected to simulate the same terrain, keep other boundary conditions unchanged, and analyze the sensitivity of the simulation results.

[0220] In the hydrodynamic simulation of pumping conditions, a segmented simulation strategy can be innovatively adopted to select different time steps according to different pumping reliability. When the water intake conditions are good and the pumping reliability is high, a larger time step is selected to improve the calculation efficiency; when the water intake conditions are poor and the pumping reliability is low, a smaller time step is used to ensure the accuracy of the simulation results at critical moments.

[0221] (6) Calibrate the riverbed roughness. Calibrate the riverbed roughness of the hydrodynamic model based on the relationship between the measured flow and the corresponding water surface line. First, measure the flow of the river section and obtain the corresponding water surface line. Then, input an assumed roughness value into the hydrodynamic simulation software and simulate according to the measured flow to obtain the water surface line of each section of the river. According to the deviation between the simulated value and the measured value of the water surface line, adjust the calculated roughness value according to the basic principles of hydrodynamics (the greater the roughness, the greater the water flow resistance and the increase in the height of the water surface line) and re-simulate. Repeat the above steps and perform repeated calculations until the simulation results are basically consistent with the measured results. At this time, it can be considered that the calibrated roughness can reflect the actual water flow resistance.

[0222] Considering that the gradient, riverbed composition, cross-sectional geometry, etc. of long-distance rivers may vary greatly, in order to ensure that the calibration results can more accurately reflect the actual terrain characteristics of the river channel, the riverbed roughness can be set in sections according to the above factors. At the same time, the calibration method can be adopted to improve the calibration efficiency.

[0223] (7) Model rationality analysis. The first step is to judge the reliability of the simulation results under different initial conditions based on the laws of hydrodynamics. For example, when other conditions remain unchanged, as the flow rate in the river increases, the water level in the river will increase, and the flow rate will also increase. The second step is to use measured data to analyze the accuracy of the simulation results, and use indicators such as correlation coefficient and Nash coefficient to judge the accuracy of the simulated water level process and the measured process. If the correlation coefficient or Nash coefficient is greater than 0.8 (and p-value < 0.05), it can be considered that the results simulated by this model have a high degree of credibility.

[0224] (8) Formulate simulation conditions and perform hydrodynamic simulation calculations. Combine the daily calculation results after iterative convergence of steps S2, S3, and S4, summarize and classify different pumping conditions and power generation conditions, and the conditions can reach hundreds or thousands, and perform hydrodynamic numerical simulations of a large number of pumping conditions and power generation conditions.

[0225] Each working condition requires setting the initial water level of the lower reservoir and the boundary conditions of the calculated flow (including the outflow of the upper reservoir power station, the outflow of the lower reservoir power station, and the outflow of the pumped flow of the hybrid pumped storage or the inflow of the power generation flow). The boundary conditions of all working conditions are input data, and the numerical simulation model of the lower reservoir hydrodynamics is applied to perform numerical simulation calculations.

[0226] Step 6: Determine the joint operation scheduling plan after hydrodynamic correction

[0227] (1) Arrangement of numerical simulation results and summary of hydrodynamic laws.

[0228] High-performance computers are used to obtain simulation results of all calculation conditions, and the simulation output data is processed in batches for the summary and analysis of hydrodynamic laws. Through the analysis results of case numerical simulation, the hydrodynamic laws can be summarized as follows:

[0229] 1) Due to the local hydrodynamic characteristics of the hybrid pumped storage and power generation, the water surface line of the lower reservoir cannot remain stable. The power generation condition will cause local Yonghe due to the outflow state of the inlet / outlet, while the pumping condition will cause a pumping funnel effect due to the inflow state of the inlet / outlet. Therefore, the water level-flow relationship of the lower reservoir inlet / outlet cannot be directly obtained using the static water level-storage capacity relationship curve, but is determined based on the storage capacity of the lower reservoir and the hydrodynamic influence of the pumping and power generation conditions of the hybrid pumped storage. The water level-flow relationship of the lower reservoir inlet / outlet is not only directly related to the storage capacity of the lower reservoir, but also directly related to the pumping flow and power generation flow of the hybrid pumped storage.

[0230] 2) The tailwater of the upper reservoir power station is located at the tail of the lower reservoir, generally upstream of the inlet / outlet of the lower hybrid pumped storage reservoir. The water level of the inlet / outlet of the lower hybrid pumped storage reservoir is directly affected by the outflow of the upper reservoir power station. When the outflow of the upper reservoir power station changes, the water flow of the inlet / outlet of the lower hybrid pumped storage reservoir also changes accordingly. Therefore, the water level-flow relationship of the inlet / outlet of the lower reservoir is directly related to the storage capacity of the lower reservoir, the pumping flow and power generation flow of the hybrid pumped storage, and also to the outflow of the upper reservoir power station.

[0231] 3) The tailwater level of the upper reservoir power station is generally directly related to its own power generation flow. At the same time, for the case of cascade connection, the tailwater level of the upper reservoir power station is also affected by the top support of the lower reservoir. When the storage capacity of the lower reservoir is large and the water level in front of the dam is close to the normal water storage level, the tailwater top support effect of the lower reservoir power station is more obvious. Therefore, the relationship between the tailwater level and flow of the upper reservoir hydropower station is not only directly related to its own power generation flow, but also related to the storage capacity of the lower reservoir.

[0232] 4) The upper reservoir power station continues to generate electricity, and the tailwater of the corresponding upper reservoir power station remains in an outflow state. The pumping and power generation operation of the hybrid pumped storage will simultaneously affect the tailwater level of the upper reservoir hydropower station. When the hybrid pumped storage power station is in power generation operation, the inlet / outlet of the lower reservoir is in an outflow state, and the hybrid pumped storage power generation flow has a certain jacking effect on the power generation tailwater level of the upper reservoir hydropower station. When the hybrid pumped storage power station is in pumping operation, the inlet / outlet of the lower reservoir is in an inflow state, which will accelerate the water flow to be pumped out of the river channel. Moreover, if the pumping flow is large, it may cause the water surface line of the lower reservoir to drop rapidly near the inlet / outlet, forming a pumping funnel effect, indicating that the pumping flow of the hybrid pumped storage will cause the power generation tailwater level of the upper reservoir hydropower station to decrease. Therefore, the relationship between the tailwater level and flow of the upper reservoir hydropower station is not only directly related to its own power generation flow and the storage capacity of the lower reservoir, but also related to the pumping flow and power generation flow of the hybrid pumped storage.

[0233] 5) The lower reservoir needs to maintain the power generation of the lower reservoir power station and continue to discharge to the downstream. When the flow of the lower reservoir to the downstream is large and greater than the net water flow, there is not enough water to replenish the water body in front of the lower reservoir dam, which will cause the water level in front of the lower reservoir dam to produce a hydraulic slope downstream, showing a non-horizontal section. Therefore, the water level in front of the dam of the lower reservoir cannot be obtained by the static water level storage capacity relationship curve through the storage capacity. The impact of the discharge of the lower reservoir should be considered, that is, the water level in front of the dam of the lower reservoir is not only directly related to the storage capacity of the lower reservoir, but also related to the outflow of the lower reservoir.

[0234] 6) The switching between the pumping and power generation conditions of the hybrid pumped storage will also affect the water level in front of the lower reservoir dam. When the hybrid pumped storage is pumping, the net inflow flow rate for the water body in front of the dam decreases, and the water level in front of the lower reservoir dam will be relatively lowered; when the hybrid pumped storage is generating electricity, the net inflow flow rate for the water body in front of the dam increases, and the water level in front of the lower reservoir dam will be relatively raised. Therefore, the water level and storage capacity relationship curve in front of the dam of the lower reservoir is directly related to the pumping flow and power generation flow of the hybrid pumped storage.

[0235] By using big data analysis methods, the hydrodynamic simulation results of all calculation conditions were summarized and statistically analyzed to obtain three sets of important water level-flow relationship curves.

[0236] The first is the relationship curve between the hybrid pumped storage inlet / outlet water level ~ lower reservoir storage capacity ~ hybrid pumped storage pumping / power generation flow ~ upper reservoir power station outflow. This is a set of four-dimensional relationship curves, which can be extracted and converted into multiple sets of hybrid pumped storage inlet / outlet water level ~ hybrid pumped storage pumping / power generation flow relationship curves under different upper reservoir outflow and lower reservoir storage capacity combinations in actual application.

[0237]

[0238] In the formula, Z down V is the water level of the lower reservoir inlet / outlet; down is the storage capacity of the lower reservoir; Q p is the pumped flow rate of hybrid pumped storage, Q g is the hybrid pumped storage power generation flow, and the two do not occur at the same time; Q upout This is the outflow from the upper reservoir.

[0239] The second is the relationship curve between the tailwater level of the upper reservoir, the outflow of the upper reservoir, the storage capacity of the lower reservoir, and the hybrid pumped storage / power generation flow. This is a set of four-dimensional relationship curves, which can be extracted and converted into multiple sets of upper reservoir tailwater level-upper reservoir outflow relationship curves under different hybrid pumped storage / power generation flows and different lower reservoir capacities in practical applications.

[0240]

[0241] In the formula, Zuptail It is the tail water level of the upper reservoir.

[0242] The third is the relationship curve between the water level in front of the lower reservoir dam, the storage capacity of the lower reservoir, the outflow of the lower reservoir, and the hybrid pumped storage / power generation flow. This is a set of four-dimensional relationship curves, which can be extracted and converted into multiple sets of relationship curves between the water level in front of the lower reservoir dam and the outflow of the lower reservoir under different hybrid pumped storage / power generation conditions and different lower reservoir storage capacities in actual application.

[0243]

[0244] In the formula, Z′ down is the water level in front of the lower reservoir dam, Q downout It is the outflow flow of the lower reservoir.

[0245] Hydrodynamically corrected joint operation scheduling scheme.

[0246] The laws summarized from the above hydrodynamic simulation are converted into a water level-flow relationship curve after big data analysis, and then converted into input conditions for hydraulic calculations. The hydrodynamic laws are fed back into the daily complementary calculation of water, wind and solar power in the upper reservoir power station in step S2, the daily complementary calculation of wind, solar and storage in the hybrid pumped storage system in step S3, and the daily reverse regulation calculation of the lower reservoir in step S4, to ensure the rationality and accuracy of the hybrid pumped storage joint operation scheduling plan.

[0247] The above embodiments are only preferred technical solutions of the present invention and should not be regarded as limiting the present invention. The protection scope of the present invention shall be the technical solutions recorded in the claims, including equivalent replacement solutions of the technical features in the technical solutions recorded in the claims. That is, equivalent replacement improvements within this scope are also within the protection scope of the present invention.

Claims

1. A hybrid pumped-storage joint operation dispatching method coupled with pumped-hydropower generation hydrodynamic simulation, characterized by: The steps are as follows: S1. Determine the boundary conditions for joint operation scheduling; S2. Establish an integrated operation and dispatching model for water, wind and solar power in the upper reservoir; S3. Establish a hybrid pumped-storage wind-solar-storage integrated operation and dispatching model; S4. Establish the counter-regulation operation and dispatching model of the lower reservoir; S5. Establish a numerical simulation model of the coupling hydrodynamics of pumping power generation in the lower reservoir; S6. Determine the joint operation scheduling plan after hydrodynamic correction.

2. The hybrid pumped-storage combined operation dispatching method coupled with pumped-water generation hydrodynamic simulation according to claim 1 is characterized by: The algorithm calculation process of step S2 is as follows: A1. Arrange the basic parameters of the upper reservoir power station, runoff data, complementary wind and solar data, and unit characteristic parameter input data; A2. According to the annual operation mode of the upper reservoir power station, annual runoff regulation calculation is carried out to determine the reservoir outflow, water level changes and water storage and release process in each month of the year; A3. Count the daily average output of complementary wind and solar power, make fine adjustments to the daily operation and dispatch of the upper reservoir power station in different months, appropriately reduce the hydropower generation flow on the day with large wind and solar power output, appropriately increase the hydropower generation flow on the day with small wind and solar power output, and update the monthly regulation calculation results; A4. Carry out the water-wind-solar complementarity calculation of the upper reservoir power station on a daily basis, and nest the power complementarity and hydraulic calculation of the hydropower station; A5. The subsequent step S3 is the hybrid pumped storage wind-solar storage daily complementary calculation and step S4 is the lower reservoir daily counter-regulation calculation, which will affect the storage capacity and water level status of the upper and lower reservoirs, thereby affecting the nested results of the hydraulic calculation and power calculation in this step S2. Therefore, a large loop iterative calculation is performed after step S4 until the storage capacity and water level status of the upper and lower reservoirs remain unchanged.

3. The hybrid pumped-storage combined operation dispatching method coupled with pumped-water generation hydrodynamic simulation according to claim 2 is characterized by: The specific process of step A4 is as follows: B1. Calculate the power generation head based on the existing upper reservoir water level and determine the expected output; B2. Calculate the wind and solar peak power to be deducted based on the hydropower base load output and channel capacity limit; B3. Hydropower is given priority in power generation. All hydropower is sent out, and wind and solar power are sent out using the idle capacity of the channel. The output that can be absorbed by wind and solar power is determined based on the surplus space in the channel, as well as the output that is abandoned; B4. Combine the hourly output of wind and solar power to determine the hourly output of hydropower; B5. Assuming the power generation flow, calculate the storage capacity and current water level of the upper and lower reservoirs in each time period, and pay attention to the situation where the hybrid pumped storage power generation is blocked. The power generation output and power generation flow of the upper reservoir power station are included in the forward output and forward flow of the hybrid pumped storage; B6. Calculate the power generation head loss, power generation head and power generation efficiency of the upper reservoir at each time period; B7. Update the power generation flow according to the hydropower output, power generation head and power generation efficiency of the unit; B8. Iterate steps B5, B6 and B7 until the power generation flow converges and remains unchanged.

4. The hybrid pumped-storage combined operation dispatching method coupled with pumped-water generation hydrodynamic simulation according to claim 1 is characterized by: The algorithm calculation process of step S3 is as follows: C1. Arrange the basic parameters of hybrid pumped storage, runoff data, complementary wind and solar data, and unit characteristic parameter input data; C2. Perform hybrid pumped storage wind-solar-storage complementation calculations on a daily basis, nesting power complementation and hybrid pumped storage hydropower calculations; C3. The subsequent step S4 is the intraday counter-regulation calculation of the lower reservoir, which will affect the storage capacity and water level status of the lower reservoir, thereby affecting the nested results of the hydraulic calculation and power calculation in this step 3. Therefore, a large loop iterative calculation is performed after step S4 until the storage capacity and water level status of the lower reservoir remain unchanged.

5. The hybrid pumped-storage combined operation dispatching method coupled with pumped-water generation hydrodynamic simulation according to claim 4 is characterized by: The specific process of step C2 is as follows: D1. Wind and solar power are sent out and consumed in channels first. The hourly wind and solar power output process is determined according to the channel capacity limit and the hybrid pumped storage capacity. The part exceeding the channel capacity is stored through hybrid pumped storage. If there is surplus wind and solar power output after energy storage, it will be considered as abandoned wind and solar power output; D2. The number of hybrid pumped-storage hydropower units should be determined by comprehensively considering the power efficiency; D3. Iteratively calculate the hourly pumping flow rate according to the determined hourly pumping input process of the hybrid pumped storage; that is, assuming the pumping flow rate, calculate the increase in pumping head, pumping head, and unit pumping efficiency in each time period, update the pumping flow rate according to the pumping input, pumping head, unit pumping efficiency, etc., and iterate the process until the pumping flow rate converges and remains unchanged; D4. According to the principle of water balance, the daily power generation water volume is determined according to the daily pumping water volume of the hybrid pumped storage; D5. Calculate the water head of hybrid pumped storage power generation and determine the expected output; D6. Similar to the iterative calculation of pumping input and pumping flow, the power generation output and power generation flow are determined through iterative calculation. That is, assuming the power generation flow, calculate the power generation head loss, power generation head, and unit power generation efficiency in each period, update the power generation flow according to the power generation output, power generation head, unit power generation efficiency, etc., and iterate the process until the power generation flow converges and remains unchanged; D7. Calculate the storage capacity and water level of the upper reservoir and the lower reservoir at each time period based on the determined hourly process of the hybrid pumped storage flow and power generation flow; D8, iterate the process D3, D4, D5, D6 and D7 until the pumping flow and power generation flow converge and remain unchanged.

6. The hybrid pumped-storage combined operation dispatching method coupled with pumped-water generation hydrodynamic simulation according to claim 1 is characterized by: The algorithm calculation process of step S4 is as follows: E1. Arrange the basic parameters of the reservoir power station, runoff data, and unit characteristic parameter input data; E2. Based on the results of wind-solar complementarity of the upper reservoir and wind-solar complementarity of the hybrid pumped-storage system, calculate the inflow flow of the lower reservoir, analyze the changing pattern of the inflow flow, and clearly divide the water supply period and water storage period; E3. Carry out the reverse regulation calculation of the lower reservoir power station every day, and find the optimal solution through trial calculation; E4. According to the determined critical water level at the end of the water supply period, determine the storage capacity and water level change process of the lower reservoir in each period, and determine the power generation head loss, power generation head, generator set efficiency and power generation output of the lower reservoir power station according to the outflow flow; E5. Combined with the daily complementary calculation of water, wind and solar power in the upper reservoir power station in step S2, the daily complementary calculation of wind and solar power in the hybrid pumped storage system in step S3, and the daily counter-regulation calculation of the lower reservoir in step S4, the storage capacity and water level status of the upper and lower reservoirs are finally determined. Therefore, it is necessary to repeat the large-loop iterative calculation of steps S2, S3, and S4 until the storage capacity and water level status of the upper and lower reservoirs remain unchanged and the nested results of the hydraulic calculation and power calculation of steps S2, S3, and S4 remain unchanged.

7. The hybrid pumped-storage combined operation dispatching method coupled with pumped-water generation hydrodynamic simulation according to claim 6 is characterized by: The specific process of step E3 is as follows: F1. Use binary search method to find the optimal solution of the critical water level at the end of the water supply period. The initial value is the average of the dead water level and the normal water level. F2. The regulating storage capacity between the normal water level and the trial water level is both the available water volume for use during the water supply period and the required water volume for storage during the water storage period. This part of water volume is used to increase the flow during the period of low water supply period and to store water for replenishment during the period of high water supply period. F3. Assuming the average outflow during the water supply period, count the time periods when the incoming water flow is less than the average outflow during the water supply period, calculate the total inflow of the corresponding period, add the total inflow water volume to the calculated available water volume during the water supply period, and divide it by the total number of time periods with less inflow to obtain the updated average outflow during the water supply period. This process needs to be iterated until the average outflow during the water supply period converges and remains unchanged, and the calculation result must meet the minimum outflow flow requirement; F4. Assuming the average outflow during the water storage period, count the time periods when the incoming water flow during the water storage period is greater than the average outflow during the water storage period, calculate the total inflow water volume of the corresponding period, subtract the calculated water storage volume during the water storage period from the total incoming water volume, and divide it by the total number of time periods with more inflow to obtain the updated average outflow flow during the water storage period. This process needs to be iterated until the average outflow flow during the water storage period converges and remains unchanged, and the calculation result must meet the minimum outflow flow requirement; F5. Determine the average outflow during the water supply period and the water storage period, and use the binary method to halve the range of judgment; If the average outflow during the water supply period is less than that during the water storage period, it means that the available water volume during the water supply period is too small and more water can be stored during the water storage period. Therefore, the trial water level should be lowered and the solution range should be reduced to the lower half of the original solution range. If the average outflow during the water supply period is greater than that during the water storage period, it indicates that the available water volume used during the water supply period is too large and the water storage should be reduced during the water storage period. Therefore, the trial water level should be raised and the solution range should be reduced to the upper half of the original solution range. F6. Through repeated iterative processes F2, F3, F4 and F5, the solution range is continuously halved until the solution range approaches the optimal solution. The optimal solution at this time is the critical water level at the end of the water supply period, indicating that the binary search method gives a reasonable scheduling process for reservoir water supply and water storage under the current inflow conditions.

8. The hybrid pumped-storage combined operation dispatching method coupled with pumped-water generation hydrodynamic simulation according to claim 1 is characterized by: The specific steps of step S5 are as follows: G1. Determine the theoretical formula and calculation method of the model. The model is built using the basic equations of fluid mechanics, but needs to be modified for the unsteady flow under pumping simulation, including the continuity equation and momentum equation; G2. Determine the model boundary conditions. In the hydraulic simulation of the lower reservoir pumping, boundary conditions need to be defined to describe the interaction between the fluid and the solid boundary, including fixed boundary conditions, free boundary conditions and inlet / outlet boundary conditions; G3. Organize terrain data and collect surveying and mapping data of the entire reservoir. The surveying and mapping accuracy must meet the accuracy requirements for supporting hydrodynamic simulation, and organize the terrain data of the riverbed and reservoir bank; G4. Perform grid division, determine the grid size, generate a two-dimensional grid of the water body, and represent the horizontal and vertical distribution of water flow by dividing the water body into small grid cells; The non-uniform grid division method is adopted to appropriately increase the area of ​​a single grid in relatively unimportant areas, and to encrypt the grids of important local river sections near the inlet / outlet, which can coordinate the relationship between grid density, calculation time and calculation accuracy. G5. Determine the calculation step size, select different simulation time steps to simulate the same terrain, keep other boundary conditions unchanged, and analyze the sensitivity of the simulation results; In the hydrodynamic simulation of pumping conditions, a segmented simulation strategy is adopted, and different time steps are selected according to different pumping reliability to ensure the accuracy of simulation results at critical moments; G6. Calibrate the riverbed roughness. Calibrate the riverbed roughness of the hydrodynamic model based on the relationship between the measured flow and the corresponding water surface line. Considering that the gradient, riverbed composition and cross-sectional geometry of long-distance rivers may vary greatly, in order to ensure that the calibration results can more accurately reflect the real river terrain characteristics, the riverbed roughness is set in sections according to the above factors. At the same time, the calibration efficiency can be improved by adopting the method of section-by-section calibration. G7,Model rationality analysis,The first step is to judge the reliability of the simulation results under different initial conditions according to the hydrodynamic laws; In the second step, the measured data are used to analyze the accuracy of the simulation results, and the correlation coefficient and Nash coefficient are used to judge the accuracy of the simulated water level process and the measured process. If the correlation coefficient or Nash coefficient is greater than 0.8 and the p-value is <0.05, it can be considered that the results simulated by this model have a high degree of credibility. G8. Develop simulation conditions and perform hydrodynamic simulation calculations. Combine the daily calculation results after iterative convergence of step S2, step S3, and step S4, summarize and classify different pumping conditions and power generation conditions. The conditions can be sorted out to reach hundreds or thousands, and a large number of hydrodynamic numerical simulations of pumping conditions and power generation conditions can be performed. For each working condition, it is necessary to set the initial water level and flow boundary conditions of the lower reservoir, make the boundary conditions of all working conditions as input data, and apply the lower reservoir hydrodynamic numerical simulation model to carry out numerical simulation calculations.

9. The hybrid pumped-storage combined operation dispatching method coupled with pumped-water generation hydrodynamic simulation according to claim 1 is characterized by: The specific steps of step S6 are as follows: H1. Use high-performance computers to obtain simulation results of all calculation conditions and process simulation output data in batches for summary and analysis of hydrodynamic laws; H2. Using big data analysis, the hydrodynamic simulation results of all calculation conditions are summarized and statistically analyzed to obtain three sets of water level-flow relationship curves; The first is the relationship curve between the water level of the hybrid pumped storage inlet / outlet, the storage capacity of the lower reservoir, the hybrid pumped storage / power generation flow, and the outflow flow of the upper reservoir power station; The second is the relationship curve among the tailwater level of the upper reservoir, the outflow of the upper reservoir, the storage capacity of the lower reservoir, and the hybrid pumped storage / power generation flow; The third is the relationship curve among the water level in front of the lower reservoir dam, the storage capacity of the lower reservoir, the outflow of the lower reservoir, and the hybrid pumped storage / power generation flow; H3. Convert the rules summarized in the above hydrodynamic simulation into the water level-flow relationship curve after big data analysis, and then convert them into the input conditions for hydraulic calculation. Feedback the hydrodynamic rules into the daily complementary calculation of water, wind and solar power in the upper reservoir power station in step S2, the daily complementary calculation of wind, solar and storage in the hybrid pumped storage in step S3, and the daily reverse regulation calculation step of the lower reservoir in step S4, to ensure the rationality and accuracy of the joint operation scheduling plan.

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