A hydro-photovoltaic complementary scheduling method considering the peak load demand of the receiving power grid

Abstract

The present invention provides a water-photovoltaic complementary scheduling method that takes into account the peak-shaving demand of the receiving-end power grid, and belongs to the technical field of water conservancy and hydropower engineering. It predicts the load process of the receiving-end power grid, combines the easy-to-adjust performance of hydropower, adjusts the short-term output process of hydropower, and responds to the power demand of the receiving-end on the basis of ensuring that the transmission channel fully absorbs the hydropower and photovoltaic power. This process adopts the requirement of smoothing the maximum value of the residual load of the receiving-end power grid, optimizes the short-term power transmission and peak-shaving capacity of the hydro-photovoltaic system, and further extends the short-term regulation mode of the hydro-photovoltaic system to the long-term optimization scheduling process, which can further tap the long-term regulation and storage capacity of the reservoir, and improve the power consumption efficiency and power transmission and peak-shaving capacity of the hydro-photovoltaic system in the long-term scheduling process. The example analysis and calculation results are reliable and effective, and can provide a reference for the operation process of the hydro-photovoltaic joint scheduling project.

Description

Technical Field

[0001] The invention relates to a water-photovoltaic complementary scheduling method taking into account the peak-shaving demand of a receiving-end power grid, and belongs to the technical field of new energy. Background Art

[0002] With the advent of the "dual carbon" era, the energy system will transform towards clean, low-carbon, safe and efficient. my country is rich in hydropower and photovoltaic resources, and has a complete reserve of hydropower and photovoltaic power generation technology. It has formed an industrial cluster advantage. Hydropower continues to play a cornerstone role in the field of renewable energy. Among the newly installed capacity, photovoltaics account for 25.25%, indicating that with the development of photovoltaic power generation technology and the reduction of costs, the proportion of new energy such as "light energy" is growing rapidly. In the face of the major historical task of "dual carbon", "hydropower and photovoltaic" will play an important role. In this case, by establishing a large-scale hydropower and photovoltaic complementary clean energy base, hydropower and photovoltaics share the transmission channel, and utilize the capacity and regulation capacity of hydropower units to optimize the grid's ability to absorb hydropower and photovoltaics, while responding to the electricity demand of the receiving end, which is of great significance to the development of clean energy and high-quality economic construction. The existing short-term regulation methods of hydropower and solar power systems mostly only consider capacity consumption or build multi-objective models for optimization calculations. The former is difficult to ensure the system's power transmission and peak-shaving performance, and the power quality of "west-to-east power transmission" is not well considered. The latter is complex to calculate, especially for large reservoirs with annual regulation capabilities. It is difficult to extend the short-term regulation method of hydropower and solar power systems to the long-term power generation plan arrangement and optimization scheduling process, and it is impossible to give full play to the regulation and storage complementarity capabilities of large reservoirs in a complete scheduling cycle. Summary of the invention

[0003] In order to overcome the shortcomings of the prior art, the present invention provides a hydro-photovoltaic complementary scheduling method that takes into account the peak-shaving demand of the receiving power grid, so as to improve the long-term power consumption capacity and power generation efficiency of the hydro-photovoltaic system and ensure the short-term power transmission peak-shaving performance of the hydro-photovoltaic system.

[0004] The technical solution of the present invention:

[0005] The present invention provides a water-photovoltaic complementary scheduling method considering the peak-shaving demand of a receiving-end power grid, which includes a short-term regulation method of a water-photovoltaic system and a long-term scheduling method of a water-photovoltaic system, including the following steps:

[0006] Step A: The short-term regulation method of the hydro-photovoltaic system takes the day as the regulation cycle and the hour as the calculation step length. By predicting the load process of the receiving end power grid on the day, predicting the photovoltaic output process on the day, knowing the daily average output of each cascade hydropower station on the day, the maximum output and minimum output constraints of each cascade hydropower station on the day, and the maximum capacity of the transmission channel, the short-term regulation calculation of the hydro-photovoltaic system is performed to obtain the short-term regulation method of the hydro-photovoltaic system;

[0007] Step B: The long-term scheduling method of the hydro-solar system takes one year as the scheduling cycle and one month as the scheduling step. It predicts the load process of the receiving power grid in each month, predicts the typical photovoltaic output process in each month, and performs long-term optimization scheduling calculation of the system based on the short-term regulation method of the hydro-solar system.

[0008] Preferably, step A specifically comprises:

[0009] Step A1: Calculate the average daily output of cascade hydropower by the average daily output of each cascade hydropower station on that day, and superimpose it with the photovoltaic output process to calculate the hydro-photovoltaic superimposed output The short-term regulation front output mode of the water-solar system is obtained, including:

[0010]

[0011]

[0012] In the formula, They are the average daily output of the i-th hydropower station, the average daily output of the cascade hydropower, and the output of the photovoltaic power station in the tth period, i = 1...L, L is the number of hydropower stations in the cascade, t = 1...T, T is the number of short-term regulation cycle periods, T = 24;

[0013] The amount of power wasted on that day W is obtained by adjusting the front output of the hydro-solar system in the short term q , specifically:

[0014]

[0015]

[0016] In the formula, The abandoned power output of the hydro-solar system in period t, representing the output of the hydro-solar system that exceeds the maximum capacity of the transmission channel, t = 1...T, T = 24;

[0017] Step A2: Adjust the average daily output of cascade hydropower to the minimum output of cascade hydropower, and calculate the combined output of hydropower and solar power The output mode of the hydropower system after sinking is obtained, including:

[0018]

[0019]

[0020]

[0021]

[0022] In the formula, N Gare the maximum and minimum output of the i-th hydropower station, the maximum and minimum output of cascade hydropower, and the maximum capacity of the transmission channel; M c is the amount of hydropower that is reduced when the average output of cascade hydropower sinks to the minimum output of cascade hydropower, i = 1...L, L is the number of hydropower stations in the cascade, t = 1...T, T is the number of short-term regulation cycle periods, and Δt is the calculation step length;

[0023] Step A3: Adjust the receiving grid load Sinking to the minimum output of cascade hydropower to form the initial boundary of hydropower guidance Specifically include:

[0024]

[0025]

[0026] In the formula, is the peak load of the receiving end of the power grid;

[0027] In the above process, hydropower guides the initial boundary Translate upward the rising output to obtain the hydropower guidance boundary Cascade hydropower output follows the hydropower guidance boundary The output of cascade hydropower can be increased by The increased hydropower is Z c , including:

[0028]

[0029]

[0030]

[0031]

[0032] In the formula, is the load process of the receiving power grid; guiding initial boundaries for hydropower; is the hydropower guidance boundary; ΔN is the translational rise output; The output of cascade hydropower can be increased in the t period; Z c For the increased hydropower;

[0033] Hydropower Guide Boundary During the rising process, when the amount of water Z increases c The amount of water M that is reduced when the average output of cascade hydropower is close to or equal to the minimum output of cascade hydropower c , which can be divided into the following two situations:

[0034] Case 1: Hydropower Guidance Boundary When the transmission channel reaches its maximum capacity, the additional hydropower Z c <M c , which means that the remaining space in the transmission channel is not enough to fully compensate for the reduced hydropower. At this time, the calculation formula for ΔN is:

[0035]

[0036]

[0037] In the formula, Initial boundary minimum for hydropower guidance;

[0038] Case 2: Hydropower Guidance Boundary When the transmission channel reaches its maximum capacity, the additional hydropower Z c ≥M c , which means that the remaining space in the transmission channel can fully compensate for the reduced amount of hydropower. At this time, the calculation formula for ΔN is:

[0039] exist Make Z c =M c ,

[0040] In the formula, the cascade hydropower can increase the output Z by iterative calculation until c Equal to M c ;

[0041] According to the above two situations, calculate the increase in output of cascade hydropower in period t The output mode of the water-solar system after short-term regulation is further obtained, including:

[0042]

[0043]

[0044]

[0045] In the formula, They are the cascade hydropower output after short-term regulation, the adjusted hydropower-solar superposition output, and the residual load of the receiving-end power grid, t=1…T, T is the number of short-term regulation cycle periods, T=24;

[0046] Step A4: Calculate the hydropower and photovoltaic power that can be absorbed by the transmission channel within the short-term dispatch cycle according to the short-term regulation method of the hydropower and photovoltaic system, including:

[0047]

[0048] Where W Tis the amount of hydropower and photovoltaic power that can be absorbed by the transmission channel, t = 1...T, T is the number of short-term regulation cycle periods, T = 24;

[0049] Step A5: According to steps A1 to A4, the short-term regulation mode of the water-light system is obtained, and the mapping function relationship f1 is introduced to be expressed as:

[0050]

[0051] Where: is the receiving-end power grid load process; It is the photovoltaic power generation process; is the average daily output of the i-th hydropower station; is the maximum output of the i-th hydropower station; is the minimum output of the ith hydropower station; N G is the maximum capacity of the transmission channel.

[0052] Preferably, it is characterized in that step B specifically comprises:

[0053] Step B1: Construct the long-term optimization scheduling objective function, as follows:

[0054]

[0055]

[0056] In the formula, W, are the annual hydropower and photovoltaic power benefits and the hydropower and photovoltaic power that can be absorbed by the transmission channel in the mth month; V m is the grid-connected unit electricity price in month m; is the load process of the receiving end power grid in the mth month; This is the typical photovoltaic output process in month m; is the average monthly output of the ith hydropower station in the cascade; is the maximum output of the i-th hydropower station in the m-th month; is the minimum output of the i-th hydropower station in the m-th month; N G is the maximum capacity of the transmission channel, t = 1…T, T is the number of short-term regulation cycle periods, T = 24, M is the number of months in the year, M = 12;

[0057] Step B2: Construct a long-term optimal scheduling constraint function for solution, including:

[0058]

[0059] Where: V i,m+1 、V i,m RQ is the water storage capacity of the reservoir at the beginning and end of the mth day of the ith hydropower station; i,m , Q i,m 、qs i,mare the inflow, power generation and abandoned water flow of the i-th hydropower station in the m-th month; QJ i,m is the flow rate from the i-1th power station to the i-th power station; Z i,min , Z i,max are the lowest and highest operating water levels of the i-th hydropower station respectively; Q i,m,min , Q i,m,max are the lower and upper limits of the discharge flow of the i-th hydropower station in period t respectively; They are the minimum and maximum outputs of the i-th hydropower station in the mth month, respectively, where the maximum output of each unit is subject to the expected output limit.

[0060] Beneficial Effects

[0061] On the basis of optimizing the transmission channel to absorb the power generation of the hydropower system, the present invention further considers the peak-shaving demand of the receiving-end power grid, takes the minimum maximum value of the residual load of the receiving-end power grid as the regulation target, and adopts an efficient and reliable short-term regulation method to obtain the cascade hydropower regulation output process. The calculation process is reliable and effective, and can be extended to the long-term optimization and scheduling process of the hydropower system. In order to fully tap the storage and complementary capabilities of large reservoirs, on the one hand, it optimizes the efficiency of absorbing the complementary electricity of hydropower and photovoltaic power, and on the other hand, it ensures the peak-shaving performance of the receiving-end power grid, providing an effective reference for the planning and design of the hydropower joint scheduling project. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 It is a short-term adjustment method for the front output of the water-light system;

[0063] Figure 2 It is the way of outputting power after the hydropower of the water-light system sinks;

[0064] Figure 3 It is the output mode of the water-light system after short-term adjustment;

[0065] Figure 4 It is the output mode after long-term optimized scheduling of the water-solar system. DETAILED DESCRIPTION

[0066] The present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant inventions, rather than to limit the inventions. It is also necessary to explain that, for ease of description, only the parts related to the relevant inventions are shown in the accompanying drawings. The present application will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0067] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The following embodiments are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0068] The embodiment is analyzed based on a scenario of a hydropower and photovoltaic energy base, where the hydropower installed capacity is 862WKW, the photovoltaic installed capacity is 300WKW, and the maximum capacity of the transmission channel is 900WKW. The cascade hydropower system as a complementary regulation medium consists of 6 reservoirs. The specific parameters are shown in Table 1:

[0069] Table 1 Scale parameters of cascade hydropower stations

[0070]

[0071] 1. Short-term adjustment method of water light system

[0072] The short-term regulation method of the hydro-solar system uses the day as the regulation cycle and the hour as the calculation step to predict the load process of the receiving power grid on that day. Predict the photovoltaic output process of the day The average daily output of each cascade hydropower station on that day is known The maximum output of each cascade hydropower station on that day is known and minimum effort Constraints, given the maximum capacity of the transmission channel N G , perform short-term adjustment calculations on the water-light system and obtain the short-term adjustment method of the water-light system, including:

[0073]

[0074]

[0075]

[0076] Where N h It is the average daily output of cascade hydropower; They are the average daily output, maximum output and minimum output of the i-th hydropower station, respectively, i=1…L, L is the number of hydropower stations in the cascade, t=1…T, T is the number of short-term regulation cycle periods, T=24; the above information is summarized in the example data in columns 1 to 6 of Table 2.

[0077] like Figure 1 As shown in the figure, the average daily output of cascade hydropower is calculated by the average daily output of each cascade hydropower station on that day, and the hourly output process of photovoltaic power is superimposed to calculate the superimposed output of water and light. The short-term regulation front output mode of the water-solar system is obtained, including:

[0078]

[0079] Where N h , They are the average daily output of cascade hydropower and the output of photovoltaic power in the tth period, and the calculated hydropower superposition output See the example data in column 8 of Table 2, the total output is 18484KW.

[0080] The amount of power wasted on the day is obtained through the intraday complementary front output of the hydro-solar system, specifically:

[0081]

[0082]

[0083] In the formula, is the abandoned power output of the hydro-solar system in the t period, representing the output part of the hydro-solar superposition output exceeding the maximum capacity of the transmission channel, t=1...T, T=24; see the example data in the 8th column of Table 2 for the embodiment. It can be seen that the hydro-solar superposition output exceeds the maximum capacity of the transmission channel by 900WKW from 12 to 15h on that day, and the total abandoned power is 118.21WKW·h, which is caused by the abandonment of water or solar power.

[0084] like Figure 2 As shown in the figure, the average daily output of cascade hydropower is adjusted to the minimum output of cascade hydropower, and the superimposed output of water and light is calculated. The output mode of the hydropower system after sinking is obtained, including:

[0085]

[0086]

[0087]

[0088] Where N G is the maximum capacity of the transmission channel; M c is the amount of water quantity reduced when the average output of cascade hydropower sinks to the minimum output of cascade hydropower, t=1…T, T is the number of short-term regulation cycle periods, Δt is the calculation step length, h; the calculated hydro-solar superposition output See the sample data in column 9 of Table 2. The purpose of this process is to reduce the output of cascade hydropower in advance and fully absorb the uncontrollable photovoltaic power.

[0089] like Figure 3 As shown, the process of adjusting the receiving-end power grid load Sinking to the minimum output of cascade hydropower to form the initial boundary of hydropower guidance Specifically include:

[0090]

[0091]

[0092] In the formula, is the peak load of the receiving end of the power grid, The calculation results are shown in the example data in column 10 of Table 2;

[0093] Hydropower Guide Initial Boundary Translate upward the rising output to obtain the hydropower guidance boundary In this process, the output of cascade hydropower varies with the hydropower guidance boundary. The output of cascade hydropower can be increased by The increased hydropower is Z c , including:

[0094]

[0095]

[0096]

[0097]

[0098] In the formula, is the load process of the receiving power grid; guiding initial boundaries for hydropower; is the hydropower guidance boundary; ΔN is the translational rise output; The output of cascade hydropower can be increased in the t period, which has three boundary constraints, namely, non-negative constraint, maximum hydropower output constraint, and maximum capacity constraint of transmission channel; Z c For the increased hydropower;

[0099] Hydropower Guide Boundary During the rising process, when the amount of water Z increases c The amount of water M that is reduced when the average output of cascade hydropower is close to or equal to the minimum output of cascade hydropower c , which can be divided into the following two situations:

[0100] Case 1: Hydropower Guidance Boundary When the transmission channel reaches its maximum capacity, the additional hydropower Z c <M c , which means that the remaining space in the transmission channel is not enough to fully compensate for the reduced hydropower. At this time, the calculation formula for ΔN is:

[0101]

[0102]

[0103] In the formula, Initial boundary minimum for hydropower guidance;

[0104] Case 2: Hydropower Guidance Boundary When the transmission channel reaches its maximum capacity, the additional hydropower Z c ≥M c, which means that the remaining space in the transmission channel can fully compensate for the reduced amount of hydropower. At this time, the calculation formula for ΔN is:

[0105] exist Make Z c =M c ,

[0106] In the formula, the cascade hydropower can increase the output Z by iterative calculation until c Equal to M c ;

[0107] According to the above two situations, calculate the increase in output of cascade hydropower in period t The output mode of the water-solar system after short-term regulation is further obtained, including:

[0108]

[0109]

[0110]

[0111] In the formula, They are the cascade hydropower output after short-term regulation, the adjusted hydro-solar superimposed output, and the residual load of the receiving power grid, t=1…T, T is the number of short-term regulation cycle periods, T=24.

[0112] Based on the above two situations, we can determine and calculate the increase in output of cascade hydropower in period t. The output mode of the water-solar system after short-term regulation is further obtained, including:

[0113]

[0114]

[0115]

[0116] In the formula, They are respectively the cascade hydropower output after short-term regulation, the adjusted hydro-solar superimposed output, and the residual load of the receiving power grid, t=1...T, T is the number of short-term regulation cycle periods, T=24; see the example data in columns 13 to 15 in Table 2 respectively.

[0117] Further, according to the output mode of the hydro-photovoltaic system after short-term regulation, the hydro-photovoltaic power that can be absorbed by the transmission channel is calculated after the short-term regulation of the hydro-photovoltaic system, including:

[0118]

[0119] Where W Tis the amount of hydropower and photovoltaic power that can be absorbed by the transmission channel, t=1…T, T is the number of short-term regulation cycle periods, T=24.

[0120] The above process is based on the sinking of cascade hydropower output, reusing the remaining capacity space of the transmission channel, combining with the load process of the receiving power grid, further compensating the cascade hydropower output, and on this basis maximizing the maximum value of the remaining load. Figure 1 and Figure 2 Output mode of hydro-photovoltaic system before and after short-term regulation. After short-term regulation, the amount of hydro-photovoltaic power that can be absorbed by the transmission channel is W. T It is 18484WKW·h, the power loss is 0WKW·h, and the remaining load is stable between 543WKW and 600WKW, with significant power consumption and peak regulation effects.

[0121] The mapping function relationship f1 is introduced to express the short-term regulation process of the water-light system as follows:

[0122]

[0123] Where: is the receiving-end grid load process, The hourly output process of photovoltaic power generation within a day. is the average daily output of the i-th hydropower station, is the maximum output of the i-th hydropower station, is the minimum output of the i-th hydropower station, N G is the maximum capacity of the transmission channel.

[0124] Table 2 Calculation process of short-term regulation example of water-light system

[0125]

[0126] 2. Long-term adjustment method of water light system

[0127] The long-term dispatching method of the hydro-solar system takes one year as the dispatching cycle and one month as the dispatching step length, and predicts the load process of the receiving power grid in each month. Predict the typical photovoltaic output process in each month Based on the above short-term regulation method of the water-solar system, long-term optimization scheduling calculation is carried out as follows:

[0128] Construct long-term optimization scheduling objective function:

[0129]

[0130]

[0131] In the formula, W, are the annual hydropower and photovoltaic power benefits and the hydropower and photovoltaic power that can be absorbed by the transmission channel in the mth month; V mis the grid-connected unit electricity price in month m; is the load process of the receiving end power grid in the mth month; This is the typical hourly photovoltaic output process in month m; is the average monthly output of the ith hydropower station in the cascade; is the maximum output of the i-th hydropower station in the m-th month; is the minimum output of the i-th hydropower station in the m-th month; N G is the maximum capacity of the transmission channel, t = 1…T, T is the number of short-term regulation cycle periods, T = 24, M is the number of months in the year, M = 12;

[0132] Construct a long-term optimization scheduling constraint function:

[0133]

[0134] V i,m+1 、V i,m RQ is the water storage capacity of the reservoir at the beginning and end of the mth day of the ith hydropower station; i,m , Q i,m 、qs i,m are the inflow, power generation and abandoned water flow of the i-th hydropower station in the m-th month; QJ i,m is the flow rate from the i-1th power station to the i-th power station; Z i,min , Z i,max are the lowest and highest operating water levels of the i-th hydropower station respectively; Q i,m,min , Q i,m,max are the lower and upper limits of the discharge flow of the i-th hydropower station in period t respectively; They are the minimum and maximum outputs of the i-th hydropower station in the mth month, respectively, where the maximum output of each unit is subject to the expected output limit.

[0135] like Figure 4 As shown in the figure, according to the objective function and the constraint function, dynamic programming is used to solve the problem. According to the calculation results, there is no power loss in each month, which effectively guarantees the optimization capacity of the hydro-photovoltaic system to absorb power. At the same time, the adjusted hydro-photovoltaic superimposed output of each month basically conforms to the load process trend of the receiving power grid in each month, which effectively responds to the power demand of the receiving end. By applying the short-term hydro-photovoltaic adjustment method to the long-term optimization scheduling process of the hydro-photovoltaic system, the photovoltaic absorption effect of large reservoirs in the long-term scheduling process can be effectively improved. On the one hand, it improves the overall hydro-photovoltaic power efficiency, and on the other hand, it takes into account the power transmission peak-shaving performance of the hydro-photovoltaic system in each scheduling cycle.

[0136] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the embodiments of the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A water-solar complementary scheduling method considering the peak load demand of the receiving power grid, characterized in that: It includes a short-term regulation method of a water-light system and a long-term scheduling method of a water-light system, and includes the following steps: Step A: The short-term regulation mode of the hydro-photovoltaic system takes the day as the regulation cycle and the hour as the calculation step length. By predicting the load process of the receiving-end power grid on the day, predicting the photovoltaic output process on the day, knowing the daily average output of each cascade hydropower station on the day, knowing the maximum output and minimum output constraints of each cascade hydropower station on the day, and knowing the maximum capacity of the transmission channel, the short-term regulation calculation of the hydro-photovoltaic system is performed to obtain the short-term regulation mode of the hydro-photovoltaic system; Step A is specifically as follows: Step A1: Calculate the average daily output of cascade hydropower by the average daily output of each cascade hydropower station on that day, and superimpose it with the photovoltaic output process to calculate the hydro-photovoltaic superimposed output The short-term regulation front output mode of the water-solar system is obtained, including: In the formula, N h , They are the average daily output of the i-th hydropower station, the average daily output of the cascade hydropower, and the output of the photovoltaic power station in the tth period, i = 1...L, L is the number of hydropower stations in the cascade, t = 1...T, T is the number of short-term regulation cycle periods, T = 24; The amount of power wasted on that day W is obtained by adjusting the front output of the hydro-solar system in the short term q , specifically: In the formula, The abandoned power output of the hydro-solar system in period t, representing the output of the hydro-solar system that exceeds the maximum capacity of the transmission channel, t = 1...T, T = 24; Step A2: Adjust the average daily output of cascade hydropower to the minimum output of cascade hydropower, and calculate the combined output of hydropower and solar power The output mode of the hydropower system after sinking is obtained, including: In the formula, N G are the maximum and minimum output of the i-th hydropower station, the maximum and minimum output of cascade hydropower, and the maximum capacity of the transmission channel; M c is the amount of hydropower that is reduced when the average output of cascade hydropower sinks to the minimum output of cascade hydropower, i = 1...L, L is the number of hydropower stations in the cascade, t = 1...T, T is the number of short-term regulation cycle periods, and Δt is the calculation step length; Step A3: Adjust the receiving grid load N t C Sinking to the minimum output of cascade hydropower to form the initial boundary of hydropower guidance Specifically include: In the formula, is the peak load of the receiving end of the power grid; In the above process, hydropower guides the initial boundary Translate upward the rising output to obtain the hydropower guidance boundary Cascade hydropower output follows the hydropower guidance boundary The output of cascade hydropower can be increased by The increased hydropower is Z c , specifically including: In the formula, is the load process of the receiving-end power grid; guiding initial boundaries for hydropower; is the hydropower guidance boundary; ΔN is the translational rise output; The output of cascade hydropower can be increased in the t period; Z c For the increased hydropower; Hydropower Guide Boundary During the rising process, when the amount of water Z increases c The amount of water M that is reduced when the average output of cascade hydropower is close to or equal to the minimum output of cascade hydropower c , which can be divided into the following two situations: Case 1: Hydropower Guidance Boundary When the transmission channel reaches its maximum capacity, the additional hydropower Z c <M c , which means that the remaining space in the transmission channel is not enough to fully compensate for the reduced hydropower. At this time, the calculation formula for ΔN is: In the formula, Initial boundary minimum for hydropower guidance; Case 2: Hydropower Guidance Boundary When the transmission channel reaches its maximum capacity, the additional hydropower Z c ≥M c , which means that the remaining space in the transmission channel can fully compensate for the reduced amount of hydropower. At this time, the calculation formula of ΔN is: exist Make Z c =M c , In the formula, the cascade hydropower can increase the output Z by iterative calculation until c Equal to M c ; According to the above two situations, calculate the increase in output of cascade hydropower in period t The output mode of the water-solar system after short-term regulation is further obtained, including: In the formula, They are the cascade hydropower output after short-term regulation, the adjusted hydropower-solar superposition output, and the residual load of the receiving-end power grid, t=1…T, T is the number of short-term regulation cycle periods, T=24; Step A4: Calculate the hydropower and photovoltaic power consumed by the transmission channel within the short-term dispatching period according to the short-term regulation mode of the hydropower and photovoltaic system, including: Where W T is the amount of hydropower and photovoltaic power consumed by the transmission channel, t = 1...T, T is the number of short-term regulation cycle periods, T = 24; Step A5: According to steps A1 to A4, the short-term regulation mode of the water-light system is obtained, and the mapping function relationship f1 is introduced to be expressed as: Where: is the receiving-end power grid load process; It is the photovoltaic power generation process; is the average daily output of the i-th hydropower station; is the maximum output of the i-th hydropower station; is the minimum output of the ith hydropower station; N G is the maximum capacity of the transmission channel; Step B: The long-term scheduling method of the hydro-photovoltaic system takes one year as the scheduling cycle and one month as the scheduling step length, predicts the load process of the receiving end power grid in each month, predicts the typical photovoltaic output process in each month, and performs long-term optimization scheduling calculation of the system based on the short-term regulation method of the hydro-photovoltaic system; Step B is specifically as follows: Step B1: Construct the long-term optimization scheduling objective function, as follows: In the formula, W, are the annual hydropower and photovoltaic power benefits and the hydropower and photovoltaic power consumed by the transmission channel in the mth month; V m is the grid-connected unit electricity price in month m; is the load process of the receiving end power grid in the mth month; This is the typical photovoltaic output process in month m; is the average monthly output of the ith hydropower station in the cascade; is the maximum output of the i-th hydropower station in the m-th month; is the minimum output of the i-th hydropower station in the m-th month; N G is the maximum capacity of the transmission channel, t = 1…T, T is the number of short-term regulation cycle periods, T = 24, M is the number of months in the year, M = 12; Step B2: Construct a long-term optimal scheduling constraint function for solution, including: Where: V i,m+1 、V i,m RQ is the water storage capacity of the reservoir at the beginning and end of the mth day of the ith hydropower station; i,m , Q i,m 、qs i,m are the inflow, power generation and abandoned water flow of the i-th hydropower station in the m-th month; QJ i,m is the flow rate from the i-1th power station to the i-th power station; Z i,min , Z i,max are the lowest and highest operating water levels of the i-th hydropower station respectively; Q i,m,min , Q i,m,max are the lower and upper limits of the discharge flow of the i-th hydropower station in period t respectively; They are the minimum and maximum outputs of the i-th hydropower station in the mth month, respectively, where the maximum output of each unit is subject to the expected output limit.

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