Daily peak regulation and compensation model method for hydropower weak-flexibility power grid in flood season

Abstract

The invention relates to a hydropower weak flexibility power grid flood season daily peak regulation and compensation model method. The method comprises the steps of obtaining a daily plan load curve, wind power, hydropower and thermal power parameters of a power grid; subtracting the wind power load from the power grid load, and updating the residual equivalent load of water and thermal power; constructing a cascade power station intraday total abandoned water minimum model; subtracting the hydropower output from the power grid residual load, and updating to obtain the thermal power residual load; constructing a thermal power total cost minimum model; calculating to obtain an output plan of each thermal power unit; opportunity cost loss caused by shutdown of the thermal power generating unit participating in deep peak regulation and deep peak regulation are compensated; a peak regulation contribution rate coefficient is introduced to carry out peak regulation benefit distribution, and the compensation amount of each power station is obtained; and distributing the deep peak regulation benefit of the deep peak regulation power station. The opportunity cost loss caused by shutdown of the thermal power generating units participating in deep peak regulation and deep peak regulation are compensated, the compensation amount of each unit is obtained, and deep peak regulation benefit distribution of the deep peak regulation power station is realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of optimized dispatching of water, thermal and wind power in power grids, and in particular relates to a daily peak regulation and compensation model method for a hydropower weakly flexible power grid during flood season. Background Art

[0002] The accelerated commissioning of intermittent renewable energy sources like wind power has placed higher demands on the grid's regulation capabilities. In some southern regions, where hydropower dominates, frequent flooding during the summer flood season has led to a dramatic increase in water inflows across river basins, resulting in a gradual loss of hydropower's excellent peak-shaving capabilities. To reduce water abandonment at power plants and ensure efficient use of clean energy, hydropower plants are forced to operate at maximum capacity, shifting to baseload grid operation. To ensure the safe operation of the grid, traditional thermal power plants must shoulder the arduous task of peak-shaving during the flood season. Deep peak-shaving is a subsidiary service for the grid's peak-shaving function.

[0003] At present, the domestic compensation mechanism for peak-shaving ancillary services is still imperfect. How to determine reasonable compensation rules for deep peak-shaving thermal power to mobilize its enthusiasm for deep peak-shaving, while also ensuring a reasonable distribution of compensation costs among non-peak-shaving power sources, is an urgent issue to be addressed. Therefore, research on flood season power generation planning and peak-shaving cost allocation for power grids lacking flexible peak-shaving sources is of great significance to ensuring the safe and stable operation of the power grid. Summary of the Invention

[0004] The technical problem of this invention is to propose a model method for daily peak-shaving and compensation during the flood season for hydropower weakly flexible power grids. Based on a layered solution approach, the daily grid plan during the flood season is divided into three layers: wind, hydropower, and thermal power. These three layers optimize and solve the remaining load to update the remaining load, thereby realizing the production of multi-energy short-term power generation plans. Furthermore, based on the daily power generation output plan of hydropower, thermal power, and wind power sources within the grid during the flood season, an improved method for compensating for ancillary service costs for daily peak-shaving of thermal power and allocating costs between power sources is used to compensate for the opportunity cost losses and deep peak-shaving caused by shutdown of thermal power units participating in deep peak-shaving. The compensation amount for each unit is then determined, and the deep peak-shaving benefits of deep peak-shaving power stations are distributed.

[0005] The technical solution of the present invention is a method for daily peak regulation and compensation model of a hydropower weak flexibility power grid during flood season, comprising the following steps: S1: Obtain the daily planned load curve of the power grid, basic parameters of wind power, hydropower and thermal power; S2: Based on the wind power guarantee and absorption principle, the grid load is reduced by the wind power load, and the remaining equivalent load of hydropower and thermal power is updated; S3: Construct a minimum model for the total daily water abandonment of cascade power stations; S4: According to the hydropower output, the grid residual load is subtracted from the hydropower output to update the thermal power residual load; S5: Construct a model to minimize the total cost of thermal power generation; S6: Calculate and obtain the output plan of each thermal power unit; S7: Compensate the thermal power units participating in deep peak load regulation for the opportunity cost losses and deep peak load regulation caused by shutdown; S8: Introduce the peak load contribution rate coefficient to distribute the peak load benefit and obtain the compensation amount for each power station; S9: Obtain the compensation amount of each power station and distribute the deep peak-shaving benefits of the deep peak-shaving power stations.

[0006] Furthermore, in step S1, wind power is fully absorbed, and the cascade hydropower stations are numbered from top to bottom as 1…m…M; the thermal power stations are numbered as 1…n…N, and the intraday planning period is 1…t…T.

[0007] Preferably, in step S3, the objective function of the minimum model for total daily water abandonment of the cascade power station is calculated as follows: ; Where, Indicates hydropower station m exist t The amount of water discarded during the period, T Indicates the total number of scheduling periods, m Indicates the power station number, M Indicates the total number of cascade power stations participating in the dispatch, Indicates the calculation period, and the period interval is 1 hour.

[0008] Furthermore, the minimum daily total water abandonment model for cascade power stations also includes constraints on water level, power station output, reservoir capacity, power generation flow, water balance, outflow, initial and final water level control, water level fluctuation, outflow fluctuation, output ramp, water level storage capacity, tailwater level storage capacity, power station output, and output limit: 1) The calculation formula for water level constraint is: ; Where, 、 Respectively represent power stations In the Water level, upper and lower limits of the time period; 2) The calculation formula for power station output constraint is: ; Where, 、 and Respectively represent power stations In the Output, upper and lower limits for the time period; 3) The calculation formula for storage capacity constraint is: ; Where, 、 Respectively represent power stations In the Storage capacity and its upper and lower limits for the time period; 4) The calculation formula for power generation flow constraint is: ; Where, 、 Respectively represent power stations In the Power generation flow, upper and lower limits for the time period; 5) The calculation formula for water balance constraint is: ; Where, 、 Respectively represent power stations In the The initial and final storage capacities of the time period; 、 Respectively represent power stations In the Inflow, abandoned water and power generation flow in each period; Indicates the time lag between upstream and downstream of the cascade power station; 6) Outflow flow constraint: The outflow flow consists of two parts: power generation flow and abandoned water flow. The calculation formula is: ; ; Where, 、 Respectively represent power stations In the Outbound flow, upper and lower limits for the time period; 7) The calculation formula for the initial and final water level control constraints is: ; ; Where, and Respectively represent reservoirs Initial water level control value, expected final water level; 8) Water level fluctuation constraint, which limits the water level fluctuation of the power station between adjacent time periods. It is determined by the power station based on navigation and comprehensive operation requirements. The calculation formula is: ; Where, Indicates power station Maximum water level fluctuation limit in a single period; 9) Constraints on outbound flow fluctuations limit the fluctuation of outbound flow between adjacent time periods. The constraints are determined by the power station based on navigation and comprehensive operation requirements. The calculation formula is: ; Where, Indicates power station Maximum outbound flow fluctuation limit in a single period; 10) The calculation formula for output climbing constraint is: ; Where, Indicates power station Maximum output increase or decrease limit in a single period; 11) The calculation formula for water level and storage capacity constraints is: ; Where, Indicates power station Water level storage capacity function; 12) The calculation formula for tailwater level storage capacity constraint is: ; ; Where, Indicates power station Water level discharge function; 13) The calculation formula for power station output constraint is: ; Where, Indicates power station The relationship function between the output and the power generation flow and power generation head; 14) The calculation formula for limiting output constraints is: ; Where, Indicates power station The relationship function between the maximum limit output and the generating head.

[0009] Preferably, in step S5, the objective function of the thermal power total cost minimization model is calculated as follows: ; ; Where, represents the cost of thermal power generation; n Indicates the power station number; Indicates thermal power unit In the Output during the time period; 、 Represent thermal power units Startup and shutdown costs; 、 Represent thermal power units The start and stop operation variables, Indicates thermal power unit exist Time period is up The power-on operation is performed during the period, otherwise ; Indicates thermal power unit exist Time period is up The shutdown operation was performed during the period, otherwise ; Indicates the operating status of the unit. Indicates that the unit is in shutdown state, otherwise it is in startup state.

[0010] Preferably, in step S5, the thermal power total cost minimization model further includes power balance, conventional peak-shaving unit power, start-up and shutdown status, unit start-up and shutdown duration and maximum start-up and shutdown times, minimum output duration, unit ramp-up, and spinning reserve constraints: 1) The calculation formula for power balance constraint is: ; Where, express t Grid load during the period; Indicates that the wind turbine is t Total output during the time period; represents the total output of hydropower in period t; 2) The calculation formula for the power constraint of conventional peak-shaving units is: ; Where, for t Conventional thermal power units during the period m Maximum and minimum output; 3) The calculation formula for the start-stop state constraint is: ; ; Where, Indicates thermal power unit n exist t The variable indicating the change of the start and stop status of the time period; 4) The calculation formula for the unit start-up and shutdown duration and the maximum start-up and shutdown times constraints is: ; ; ; Where, 、 Represent thermal power units n Minimum start and stop duration; Indicates thermal power unit n The upper limit of the number of startups during the scheduling period; 5) The calculation formula for the minimum output duration constraint is: ; Where, Indicates the unit n The minimum number of periods that must be maintained at the highest and lowest points during a round of output increase or decrease; 6) The calculation formula for the unit climbing constraint is: ; Where, For thermal power units n Maximum climbing output; 7) The calculation formula for spinning reserve constraint is: ; ; Where, Indicates the grid reserve rate.

[0011] Furthermore, step S7 includes using the method of compensating for the auxiliary service costs of thermal power's intra-day peak-shaving and sharing the costs among power sources based on the planned daily power generation output of hydropower, thermal power and wind power sources in the grid during the flood season to compensate for the opportunity cost losses and deep peak-shaving caused by the shutdown of thermal power units participating in deep peak-shaving.

[0012] Furthermore, in step S7, the calculation formula for the compensation capacity to be the normal minimum output is: ; ; ; Where, Indicates deep peak-shaving thermal power units n exist t Compensation income for the period, Indicates thermal power units with non-deep peak regulation t Average profit during the period, Indicates non-deep peak-shaving thermal power units n exist t Income during the period, Indicates non-deep peak-shaving thermal power units n exist t The cost of the period, Indicates deep peak-shaving thermal power units n The critical output of deep peak regulation, J Indicates the number of conventional non-deep peak-shaving thermal power units, Indicates deep peak-shaving thermal power units n exist t Peak load status of the time period, if , the unit is in deep peak regulation state, Indicates that the unit is in shutdown state.

[0013] Preferably, in step S8, the calculation formula for the allocation of the peak load benefit is: ; ; Where, express n Power station No. t The apportionment of expenses for each period, express n Power station No. t The actual output of the period, Indicates the n The average daily output of power station No. Indicates the daily average load of the power grid.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1) This paper proposes a model method for daily peak-shaving and compensation during the flood season for a hydropower weakly flexible power grid. Based on a hierarchical solution, the daily planning of the power grid during the flood season is divided into three layers: wind power layer, hydropower layer, and thermal power layer. By optimizing and solving each layer to update the residual load, the short-term power generation plan of multiple energy sources is realized. 2) This invention comprehensively considers the complex constraints of the power grid, power stations, and units, and solves and obtains the optimal hydropower operation plan with the goal of minimizing the total amount of hydropower abandoned in the flood season. With the goal of minimizing total operating costs, it also obtains the optimal power generation combination of thermal power units and determines the daily power generation operation plan for each power source in the grid.

[0015] 3) Based on the overall output process of the daily power generation plans of hydropower, thermal power and wind power sources in the grid during the flood season, the present invention adopts a newly proposed method for compensating for the auxiliary service costs of thermal power intra-day peak-shaving and other compensation sharing methods among power sources to economically compensate for the cost losses of thermal power units and the losses of deep peak-shaving.

[0016] 4) The present invention replaces the traditional method of calculating the amount of grid electricity with the profit of each power station in each period of deep peak regulation of the grid, and at the same time introduces the peak regulation contribution rate coefficient to distribute the peak regulation benefits, obtain the compensation amount of each power station, and realize the deep peak regulation benefit distribution of deep peak regulation power stations. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be further described below with reference to the accompanying drawings and examples.

[0018] Figure 1 This is a flow chart of a method for solving a daily peak regulation and compensation model for a hydropower weakly flexible power grid during flood season according to an embodiment of the present invention; Figure 2 A schematic diagram of a daily load process of a power grid according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the total wind power output process in a day according to an embodiment of the present invention; Figure 4 Schematic diagram of the total daily output process of cascade hydropower according to an embodiment of the present invention; Figure 5 Schematic diagram of the daily output process of a thermal power unit according to an embodiment of the present invention. DETAILED DESCRIPTION

[0019] like Figure 1 As shown, a method for daily peak regulation and compensation model of a hydropower weak flexibility power grid during flood season includes the following steps: S1: Obtain the daily planned load curve of the power grid, and basic parameters of wind power, hydropower, and thermal power.

[0020] In step S1, wind power is fully absorbed, and the cascade hydropower stations are numbered from top to bottom as 1…m…M; the thermal power stations are numbered 1…n…N, and the intraday planning period is 1…t…T.

[0021] Preferably, in step S3, the objective function of the minimum model for total daily water abandonment of the cascade power station is calculated as follows: ; Where, Indicates hydropower station m exist t The amount of water discarded during the period, T Indicates the total number of scheduling periods, m Indicates the power station number, M Indicates the total number of cascade power stations participating in the dispatch, Indicates the calculation period.

[0022] The minimum daily total water abandonment model for cascade power stations also includes constraints on water level, power station output, reservoir capacity, power generation flow, water balance, outflow, initial and final water level control, water level fluctuation, outflow fluctuation, output ramp, water level storage capacity, tailwater level storage capacity, power station output, and output limit: 1) The calculation formula for water level constraint is: ; Where, 、 Respectively represent power stations In the Water level, upper and lower limits of the time period; 2) The calculation formula for power station output constraint is: ; Where, 、 and Respectively represent power stations In the Output, upper and lower limits for the time period; 3) The calculation formula for storage capacity constraint is: ; Where, 、 Respectively represent power stations In the Storage capacity and its upper and lower limits for the time period; 4) The calculation formula for power generation flow constraint is: ; Where, 、 Respectively represent power stations In the Power generation flow, upper and lower limits for the time period; 5) The calculation formula for water balance constraint is: ; Where, 、 Respectively represent power stations In the The initial and final storage capacities of the time period; 、 Respectively represent power stations In the Inflow, abandoned water and power generation flow in each period; Indicates the time lag between upstream and downstream of the cascade power station; 6) Outflow flow constraint: The outflow flow consists of two parts: power generation flow and abandoned water flow. The calculation formula is: ; ; Where, 、 Respectively represent power stations In the Outbound flow, upper and lower limits for the time period; 7) The calculation formula for the initial and final water level control constraints is: ; ; Where, and Respectively represent reservoirs Initial water level control value, expected final water level; 8) Water level fluctuation constraint, which limits the water level fluctuation of the power station between adjacent time periods. It is determined by the power station based on navigation and comprehensive operation requirements. The calculation formula is: ; Where, Indicates power station Maximum water level fluctuation limit in a single period; 9) Constraints on outbound flow fluctuations limit the fluctuation of outbound flow between adjacent time periods. The constraints are determined by the power station based on navigation and comprehensive operation requirements. The calculation formula is: ; Where, Indicates power station Maximum outbound flow fluctuation limit in a single period; 10) The calculation formula for output climbing constraint is: ; Where, Indicates power station Maximum output increase or decrease limit in a single period; 11) The calculation formula for water level and storage capacity constraints is: ; Where, Indicates power station Water level storage capacity function; 12) The calculation formula for tailwater level storage capacity constraint is: ; ; Where, Indicates power station Water level discharge function; 13) The calculation formula for power station output constraint is: ; Where, Indicates power station The relationship function between the output and the power generation flow and power generation head; 14) The calculation formula for limiting output constraints is: ; Where, Indicates power station The relationship function between the maximum limit output and the generating head.

[0023] Preferably, in step S5, the calculation formula of the objective function of the thermal power total cost minimum model is: ; ; Where, represents the cost of thermal power generation; n Indicates the power station number; Indicates thermal power unit In the Output during the time period; 、 Represent thermal power units Startup and shutdown costs; 、 Represent thermal power units The start and stop operation variables, Indicates thermal power unit exist Time period is up The power-on operation is performed during the period, otherwise ; Indicates thermal power unit exist Time period is up The shutdown operation was performed during the period, otherwise ; Indicates the operating status of the unit. Indicates that the unit is in shutdown state, otherwise it is in startup state.

[0024] S2: Based on the principle of wind power guarantee and absorption, the wind power load is subtracted from the grid load, and the remaining equivalent load of hydropower and thermal power is updated.

[0025] S3: Construct a minimum model for the total daily water abandonment of cascade power stations.

[0026] S4: Based on the hydropower output, the grid residual load is subtracted from the hydropower output to update the thermal power residual load.

[0027] S5: Construct a model to minimize the total cost of thermal power generation.

[0028] In step S5, the thermal power total cost minimization model also includes power balance, conventional peak-shaving unit power, start-up and shutdown status, unit start-up and shutdown duration and maximum start-up and shutdown times, minimum output duration, unit ramp-up, and spinning reserve constraints: 1) The calculation formula for power balance constraint is: ; Where, express t Grid load during the period; Indicates that the wind turbine is tTotal output during the time period; represents the total output of hydropower in period t; 2) The calculation formula for the power constraint of conventional peak-shaving units is: ; Where, for t Conventional thermal power units during the period m Maximum and minimum output; 3) The calculation formula for the start-stop state constraint is: ; ; Where, Indicates thermal power unit n exist t The variable indicating the change of the start and stop status of the time period; 4) The calculation formula for the unit start-up and shutdown duration and the maximum start-up and shutdown times constraints is: ; ; ; Where, 、 Represent thermal power units n Minimum start and stop duration; Indicates thermal power unit n The upper limit of the number of startups during the scheduling period; 5) The calculation formula for the minimum output duration constraint is: ; Where, Indicates the unit n The minimum number of periods that must be maintained at the highest and lowest points during a round of output increase or decrease; 6) The calculation formula for the unit climbing constraint is: ; Where, For thermal power units n Maximum climbing output; 7) The calculation formula for spinning reserve constraint is: ; ; Where, Indicates the grid reserve rate.

[0029] S6: Calculate and obtain the output plan of each thermal power unit; S7: Compensate the thermal power units participating in deep peak load regulation for the opportunity cost losses and deep peak load regulation caused by shutdown; Step S7 includes compensating for the opportunity cost loss and deep peak regulation caused by the shutdown of thermal power units participating in deep peak regulation by using the thermal power daily peak regulation auxiliary service fee compensation and power source sharing method based on the daily power generation plan output of hydropower, thermal power and wind power sources in the grid during the flood season.

[0030] In step S7, the calculation formula for the compensation capacity to be the normal minimum output is: ; ; ; Where, Indicates deep peak-shaving thermal power units n exist t Compensation income for the period, Indicates thermal power units with non-deep peak regulation t Average profit during the period, Indicates non-deep peak-shaving thermal power units n exist t Income during the period, Indicates non-deep peak-shaving thermal power units n exist t The cost of the period, Indicates deep peak-shaving thermal power units n The critical output of deep peak regulation, J Indicates the number of conventional non-deep peak-shaving thermal power units, Indicates deep peak-shaving thermal power units n exist t Peak load status of the time period, if , the unit is in deep peak regulation state, Indicates that the unit is in shutdown state.

[0031] S8: Introduce the peak load contribution rate coefficient to distribute the peak load benefit and obtain the compensation amount for each power station; In step S8, the calculation formula for the allocation of the peak load benefit is: ; ; Where, express n Power station No. t The apportionment of expenses for each period, express n Power station No. t The actual output of the period, Indicates the n The average daily output of power station No. Indicates the daily average load of the power grid.

[0032] S9: Obtain the compensation amount of each power station and distribute the deep peak-shaving benefits of the deep peak-shaving power stations.

[0033] The application method is illustrated using an example application in a regional power grid under the jurisdiction of a southern provincial power grid. This power grid is primarily composed of hydropower and thermal power, with a higher proportion of hydropower. The large-scale commissioning of clean energy sources such as wind power further increases the difficulty of daily grid dispatch during the flood season, forcing thermal power units to implement deep peak-shaving to ensure safe grid operation. However, the current low level of peak-shaving compensation has resulted in a low willingness of thermal power plants to participate in deep peak-shaving.

[0034] A regional power grid under the jurisdiction of the power grid is selected, with a total of 5 thermal power units, 5 cascade hydropower stations and a wind farm. According to the actual situation, the model sets all thermal power units to participate in basic peak regulation, and two 300MW units provide deep peak regulation services. The basic peak regulation limit is set to 50%, the non-oil peak regulation depth limit is 60%, and the oil-injection extreme peak regulation depth limit is set to 70%. The actual power grid load process on a certain day during the flood season is selected, such as Figure 2 , the installed capacity of the wind power plant is 400MW, and the daily plan is provided by the wind power forecast system, such as Figure 3 , fully accepted according to the relevant requirements of the state for clean energy. The current implementation of the thermal power auxiliary service deep peak load compensation standard refers to the Southern Region Grid-connected Power Plant Ancillary Service Management Implementation Rules, as shown in Table 1: Table 1

[0035] The basic parameters of hydropower, wind power, and thermal power station units are shown in Tables 2 and 3. The on-grid electricity prices for hydropower, wind power, and thermal power within the grid are approved by the provincial and regional price bureaus and announced by all power plants for unified implementation.

[0036] Table 2

[0037] Table 3

[0038] According to the method proposed in this patent, the daily power generation plan of the above regional power grid is prepared and the peak load auxiliary service benefit is apportioned. The output plans of different types of power sources are obtained as follows: Figure 4 and Figure 5 The results of the allocation of peak load ancillary service costs are shown in Table 4.

[0039] Table 4

[0040] like Figure 4 and Figure 5As shown in the figure, the daily planning process for thermal power and hydropower and the apportionment of peak-shaving auxiliary service costs calculated using this patented method show that during the flood season, cascade hydropower has a large water inflow. To ensure the efficient use of clean energy and minimize water abandonment in cascade power stations, hydropower operates at a high output throughout the day, transferring the power to the grid to bear the base load. However, due to the obstruction of hydropower, the power station cannot operate at its installed capacity, and the calculated results are consistent with the actual operation. In addition, due to the influence of intraday head fluctuations, the cascade hydropower has experienced a certain degree of output fluctuation. On top of the loss of hydropower's peak-shaving capacity during the flood season, this has exacerbated the peak-shaving pressure on the power grid.

[0041] As shown in the allocation results in Table 4, the existing model based on the compensation standard fixed by the current regulations and the compensation model proposed in this invention were used to conduct compensation and apportionment research on deep peak-shaving of thermal power. The deep peak-shaving thermal power units in the existing model did not consider the compensation of opportunity costs, resulting in no income when the units were shut down, further eliminating the enthusiasm of the thermal power units for deep peak-shaving. The present invention takes into account the opportunity cost lost due to deep peak-shaving and increases the intensity of deep peak-shaving compensation. This allows deep peak-shaving thermal power units to obtain equivalent power generation income compared to conventional thermal power units. In addition, the present invention proposes that the apportionment amount of each power station is affected by the net profit of power generation and peak-shaving contribution of each power station. The compensation allocation results of the model proposed in this invention are more reasonable.

[0042] The above embodiments are merely preferred technical solutions of the present invention and should not be construed as limiting the present invention. The scope of protection of the present invention shall be the technical solutions recited in the claims, including equivalent alternatives to the technical features of the technical solutions recited in the claims. In other words, equivalent alternatives and improvements within this scope are also within the scope of protection of the present invention.

Claims

1. A method for daily peak regulation and compensation model of hydropower weak flexibility power grid during flood season, characterized by: The following steps are involved: S1: Obtain the daily planned load curve of the power grid, basic parameters of wind power, hydropower and thermal power; S2: Based on the wind power guarantee and absorption principle, the grid load is reduced by the wind power load, and the remaining equivalent load of hydropower and thermal power is updated; S3: Construct a minimum model for the total daily water abandonment of cascade power stations; S4: According to the hydropower output, the grid residual load is subtracted from the hydropower output to update the thermal power residual load; S5: Construct a model to minimize the total cost of thermal power generation; S6: Calculate and obtain the output plan of each thermal power unit; S7: Compensate the thermal power units participating in deep peak load regulation for the opportunity cost losses and deep peak load regulation caused by shutdown; S8: Introduce the peak load contribution rate coefficient to distribute the peak load benefit and obtain the compensation amount for each power station; S9: Obtain the compensation amount of each power station and distribute the deep peak-shaving benefits of the deep peak-shaving power stations.

2. According to claim 1, a method for daily peak load regulation and compensation model of hydropower weak flexibility power grid during flood season, characterized in that: In step S3, the objective function of the minimum model for total daily water abandonment of the cascade power stations is calculated as follows: ； Where, Indicates hydropower station m exist t The amount of water discarded during the period, T Indicates the total number of scheduling periods, m Indicates the power station number, M Indicates the total number of cascade power stations participating in the dispatch, Indicates the calculation period, and the period interval is 1 hour.

3. According to claim 2, a method for daily peak load regulation and compensation model of hydropower weak flexibility power grid during flood season, characterized in that: The minimum model for the total daily water abandonment of the cascade power station also includes constraints on output and output limitation, including water level, power station output, reservoir capacity, power generation flow, water balance, outflow, initial and final water level control, water level fluctuation, outflow fluctuation, output ramp, water level storage capacity, tailwater level storage capacity, power station output and output limitation constraints.

4. A method for daily peak load regulation and compensation model of a hydropower weak flexibility power grid during flood season according to claim 3, characterized in that: The calculation formula of the output and the output limiting constraint conditions is: 1) The calculation formula for water level constraint is: ； Where, 、 Respectively represent power stations In the Water level, upper and lower limits of the time period; 2) The calculation formula for power station output constraint is: ； Where, 、 and Respectively represent power stations In the Output, upper and lower limits for the time period; 3) The calculation formula for storage capacity constraint is: ； Where, 、 Respectively represent power stations In the Storage capacity and its upper and lower limits for the time period; 4) The calculation formula for power generation flow constraint is: ； Where, 、 Respectively represent power stations In the Power generation flow, upper and lower limits for the time period; 5) The calculation formula for water balance constraint is: ； Where, 、 Respectively represent power stations In the The initial and final storage capacities of the time period; 、 Respectively represent power stations In the Inflow, abandoned water and power generation flow in each period; Indicates the time lag between upstream and downstream of the cascade power station; 6) Outflow flow constraint: The outflow flow consists of two parts: power generation flow and abandoned water flow. The calculation formula is: ； ； Where, 、 Respectively represent power stations In the Outbound flow, upper and lower limits for the time period; 7) The calculation formula for the initial and final water level control constraints is: ； ； Where, and Respectively represent reservoirs Initial water level control value, expected final water level; 8) Water level fluctuation constraint, which limits the water level fluctuation of the power station between adjacent time periods. It is determined by the power station based on navigation and comprehensive operation requirements. The calculation formula is: ； Where, Indicates power station Maximum water level fluctuation limit in a single period; 9) Constraints on outbound flow fluctuations limit the fluctuation of outbound flow between adjacent time periods. The constraints are determined by the power station based on navigation and comprehensive operation requirements. The calculation formula is: ； Where, Indicates power station Maximum outbound flow fluctuation limit in a single period; 10) The calculation formula for output climbing constraint is: ； Where, Indicates power station Maximum output increase or decrease limit in a single period; 11) The calculation formula for water level and storage capacity constraints is: ； Where, Indicates power station Water level storage capacity function; 12) The calculation formula for tailwater level storage capacity constraint is: ； ； Where, Indicates power station Water level discharge function; 13) The calculation formula for power station output constraint is: ； Where, Indicates power station The relationship function between the output and the power generation flow and power generation head; 14) The calculation formula for limiting output constraints is: ； Where, Indicates power station The relationship function between the maximum limit output and the generating head.

5. The method for daily peak load regulation and compensation model of hydropower weak flexibility power grid during flood season according to claim 1 is characterized in that: In step S5, the objective function of the thermal power total cost minimization model is calculated as follows: ； ； Where, represents the cost of thermal power generation; n Indicates the power station number; Indicates thermal power unit In the Output during the time period; 、 Represent thermal power units Startup and shutdown costs; 、 Represent thermal power units The start and stop operation variables, Indicates thermal power unit exist Time period is up The power-on operation is performed during the period, otherwise ; Indicates thermal power unit exist Time period is up The shutdown operation was performed during the period, otherwise ; Indicates the operating status of the unit. Indicates that the unit is in shutdown state, otherwise it is in startup state.

6. A method for daily peak load regulation and compensation model of a hydropower weak flexibility power grid during flood season according to claim 5, characterized in that: In step S5, the thermal power total cost minimization model also includes power balance, conventional peak-shaving unit power, start-up and shutdown status, unit start-up and shutdown duration and maximum start-up and shutdown times, minimum output duration, unit ramping, and spinning reserve constraints.

7. A method for daily peak load regulation and compensation model of a hydropower weak flexibility power grid during flood season according to claim 6, characterized in that: The calculation formula of the constraint of the thermal power total cost minimum model is: 1) The calculation formula for power balance constraint is: ； Where, express t Grid load during the period; Indicates that the wind turbine is t Total output during the time period; represents the total output of hydropower in period t; 2) The calculation formula for the power constraint of conventional peak-shaving units is: ； Where, for t Conventional thermal power units during the period m Maximum and minimum output; 3) The calculation formula for the start-stop state constraint is: ； ； Where, Indicates thermal power unit n exist t The variable indicating the change of the start and stop status of the time period; 4) The calculation formula for the unit start-up and shutdown duration and the maximum start-up and shutdown times constraints is: ； ； ； Where, 、 Represent thermal power units n Minimum start and stop duration; Indicates thermal power unit n The upper limit of the number of startups during the scheduling period; 5) The calculation formula for the minimum output duration constraint is: ； Where, Indicates the unit n The minimum number of periods that must be maintained at the highest and lowest points during a round of output increase or decrease; 6) The calculation formula for the unit climbing constraint is: ； Where, For thermal power units n Maximum climbing output; 7) The calculation formula for spinning reserve constraint is: ； ； Where, Indicates the grid reserve rate.

8. The method for daily peak load regulation and compensation model of hydropower weak flexibility power grid during flood season according to claim 1, characterized in that: The step S7 includes compensating for the opportunity cost loss and deep peak regulation caused by the shutdown of the thermal power units participating in deep peak regulation by using the thermal power daily peak regulation auxiliary service fee compensation and power source sharing method according to the daily power generation plan of hydropower, thermal power and wind power sources in the grid during the flood season.

9. A method for daily peak load regulation and compensation model of a hydropower weak flexibility power grid during flood season according to claim 8, characterized in that: In step S7, the calculation formula for the compensation capacity to be the normal minimum output is: ； ； ； Where, Indicates deep peak-shaving thermal power units n exist t Compensation income for the period, Indicates thermal power units with non-deep peak regulation t Average profit during the period, Indicates non-deep peak-shaving thermal power units n exist t Income during the period, Indicates non-deep peak-shaving thermal power units n exist t The cost of the period, Indicates deep peak-shaving thermal power units n The critical output of deep peak regulation, J Indicates the number of conventional non-deep peak-shaving thermal power units, Indicates deep peak-shaving thermal power units n exist t Peak load status of the time period, if , the unit is in deep peak regulation state, Indicates that the unit is in shutdown state.

10. A method for daily peak load regulation and compensation model of a hydropower weak flexibility power grid during flood season according to claim 1, characterized in that: In step S8, the calculation formula for the allocation of the peak load benefit is: ； ； Where, express n Power station No. t The apportionment of expenses for each period, express n Power station No. t The actual output of the period, Indicates the n The average daily output of power station No. Indicates the daily average load of the power grid.

Images