A simulation method for integrated scheduling and operation of cascade hydropower, wind power, solar power and storage in a river basin considering long-term and short-term nested correction

Abstract

This invention provides a simulation method for the integrated scheduling and operation of watershed-level hydropower, wind power, solar power, and energy storage systems, considering long-term and short-term nested corrections. The method includes: constructing and solving a medium- to long-term optimized scheduling model for integrated watershed-level hydropower, wind power, solar power, and energy storage systems to obtain a medium- to long-term energy complementary scheduling scheme; and constructing a long- to short-term nested correction model to refine the power output process of each power source in the integrated watershed-level hydropower, wind power, solar power, and energy storage system to obtain a short-term energy complementary scheduling scheme. Based on the medium- to long-term optimized scheduling, this invention further constructs a long- to short-term nested correction model, fully considering the random fluctuations in short-term wind and solar power output and the short-term regulation capabilities of hydropower stations and pumped storage power stations. This enables the effective long-term absorption and short-term grid connection of integrated watershed-level hydropower, wind power, solar power, and energy storage systems under high-proportion renewable energy penetration, meeting the refined requirements of multi-energy complementary scheduling systems for evaluating indicators such as renewable energy absorption rates.

Description

Technical Field

[0001] The present invention belongs to the technical field of dispatching and operating integrated multi-energy complementary bases of cascade water, wind, solar and storage in a river basin, and specifically relates to a dispatching and operating simulation method of integrated multi-energy complementary bases of cascade water, wind, solar and storage in a river basin considering long-term and short-term nested correction. Background Art

[0002] Under the trend of global energy transformation, the installed capacity of new energy such as wind power and photovoltaics has continued to rise. In order to overcome the huge challenges posed by the uncertainty, randomness and intermittent characteristics of wind power and photovoltaic output to the safe operation of the power grid, the integrated development of water, wind, solar and storage has become one of the important forms of increasing the space for wind and solar grid connection and promoting the development of new energy.

[0003] The types of power sources and the number of power stations in the integrated multi-energy complementary base of cascade water, wind, solar and storage in the basin are large, and the optimization and scheduling of the entire system is extremely complex. In the existing technology, only the medium- and long-term optimization and scheduling mode of the integrated water, wind, solar and storage in the basin is adopted to obtain the medium- and long-term scale complementary scheduling plan. This method has the following shortcomings: under the medium- and long-term optimization and scheduling mode of the integrated water, wind, solar and storage in the basin, only the medium- and long-term scheduling rules of runoff uncertainty are considered, while the random volatility of short-term wind and solar output and the regulation capacity of short-term hydropower stations and pumped storage power stations are not considered enough, which is not conducive to the effective acceptance of long-term consumption and short-term grid connection of the integrated multi-energy complementary base of water, wind, solar and storage under high proportion of new energy penetration, and cannot meet the refined requirements of the multi-energy complementary scheduling system for evaluating indicators such as new energy absorption rate and transmission line utilization hours. Summary of the invention

[0004] In view of the defects of the prior art, the present invention provides a basin cascade water, wind, solar and storage integrated scheduling and operation simulation method considering long-term and short-term nested corrections, which can effectively solve the above problems.

[0005] The technical solution adopted by the present invention is as follows:

[0006] The present invention provides a basin cascade water, wind, solar and storage integrated scheduling and operation simulation method considering long-term and short-term nested correction, comprising the following steps:

[0007] Step S1: Taking the maximum power generation or maximum power generation benefit of the integrated multi-energy complementary base of cascade water, wind, solar and storage in the basin as the scheduling target, comprehensively considering the constraints of various power sources and transmission lines, and constructing a medium- and long-term optimal scheduling model for the integrated multi-energy complementary base of cascade water, wind, solar and storage in the basin;

[0008] Step S2: Solve the medium- and long-term optimal dispatch model of the integrated water, wind, solar and storage cascade in the basin to obtain the medium- and long-term scale complementary dispatch plan of water, wind and solar;

[0009] Step S3: Taking the maximum new energy absorption rate or the best source-grid matching of the integrated multi-energy complementary base of water, wind, solar and storage in the basin as the scheduling target, a long-short-term nested correction model is constructed;

[0010] Step S4: Based on the long-short term nested correction model, the output process of each power source of the cascade water-wind-solar-storage integrated multi-energy complementary base in the basin is refined to obtain a short-term scale power complementary dispatching plan for water-wind-solar-storage to guide the dispatching and operation of the cascade water-wind-solar-storage integrated multi-energy complementary base in the basin.

[0011] Preferably, in step S1, the constraints of each power source and transmission line include hydraulic connection of cascade hydropower stations, water balance constraints of hydropower stations, upper and lower limits and amplitude constraints of water levels of hydropower stations, water level constraints at the beginning and end of the dispatching period of hydropower stations, outflow constraints of hydropower stations, output constraints of hydropower stations, head constraints of hydropower stations, output constraints of wind power stations, output constraints of photovoltaic power stations and output constraints of transmission lines.

[0012] Preferably, in step S1, the expression of the scheduling target F1 with the maximum power generation is:

[0013]

[0014] Where: t is the time period number used in the medium- and long-term optimization scheduling model of the integrated water, wind, solar and storage cascade in the basin; Δt t is the length of time period t; T is the number of time periods t included in the scheduling period; N w 、N s and N h They are the number of wind power stations, photovoltaic power stations and hydropower stations participating in the dispatching and operation of the cascade water-wind-solar-storage integrated multi-energy complementary base in the basin; and are the average outputs of wind power station j, photovoltaic power station k and hydropower station l in time period t; j = 1, 2, ..., N w ; k = 1, 2, ..., N s ; l=1,2,...,N h ;

[0015] The expression of the dispatching target F2 with the maximum power generation benefit is:

[0016]

[0017] in: and are the power generation benefits of wind power station j, photovoltaic power station k and hydropower station l in time period t respectively; and are the on-grid electricity prices of wind power station j, photovoltaic power station k and hydropower station l in time period t.

[0018] Preferably, step S2 is specifically as follows: solving the medium- and long-term optimization scheduling model of the integrated water, wind, solar and storage cascade in the basin to obtain the optimal medium- and long-term operation mode of the power source that meets the scheduling objectives and constraints, including: the average output of each hydropower station, wind power station and photovoltaic power station in each time period t during the scheduling period, and the water level of each hydropower station in each time period t; wherein, for hydropower station l, its average output in time period t is expressed as The water level at the end of time period t is expressed as

[0019] Preferably, step S3 is specifically as follows: taking the maximum new energy absorption rate or the best source-grid matching of the basin cascade water, wind, light and storage integrated multi-energy complementary base as the scheduling target, and solving the average output of the hydropower station l in time period t based on the medium- and long-term optimization scheduling model of the basin cascade water, wind, light and storage integration And the predicted output of wind power station j in each time period t' during the dispatch period And the output of photovoltaic power station k in each time period t' during the dispatch period Taking into account the TTC restrictions of transmission lines or grid requirements, the characteristics of hydropower stations and pumped storage power stations, a long-short-term nested correction model is constructed; where t' is the time period number used in the long-short-term nested correction model.

[0020] Preferably, the expression of the dispatching target F3 with the maximum new energy absorption rate of the basin cascade water, wind, light and storage integrated multi-energy complementary base is:

[0021]

[0022] Where: Δt′ t is the length of time period t', Δt' t Less than Δt t ; T' is the number of time periods t' included in the scheduling period; N st The number of all pumped-storage power stations participating in the dispatching and operation of the cascade water, wind, solar and storage integrated multi-energy complementary base in the basin; and are the average outputs of wind power station j, photovoltaic power station k, hydropower station l and pumped storage power station m in time period t'; Pd st The power generation corresponding to the difference in storage capacity between the beginning and the end of the dispatch period of the pumped storage power station;

[0023] The expression of the dispatching target F4 with the best source-grid matching of the integrated multi-energy complementary base of water, wind, solar and storage in the basin is:

[0024]

[0025] Among them: PR t' is the residual load of the power grid in time period t', that is, the output N of the power transmission line required by the power grid in time period t'load,t' The actual output P of the transmission line in time period t' t' The difference, PR t' =N load,t' -P t' ; is the average grid residual load during the dispatch period, that is,

[0026] Preferably, step S4 specifically includes:

[0027] Step S4.1, using the long-short term nested correction model, determine the average output of hydropower station l in period t'

[0028] Step S4.2, using the long-short term nested correction model, determine the average output of wind power station j in period t' and the average output of photovoltaic power station k in time period t'

[0029] Step S4.3, using the long-short term nested correction model, determine the average output of the pumped storage power station m in period t'

[0030] Step S4.4, the average output of hydropower station l in time period t' obtained according to steps S4.1, S4.2 and S4.3 The average output of wind power station j in period t' Average output of photovoltaic power station k in time period t' and the average output of pumped storage power station m in period t' Re-evaluate the new energy absorption rate and transmission line utilization hours indicators of the basin's cascade integrated multi-energy complementary base of water, wind, solar and storage.

[0031] Preferably, step S4.1 specifically includes:

[0032] Step S4.1.1: The time length of the period t used in the medium- and long-term optimization scheduling model of the integrated water, wind, solar and storage cascade in the basin is Δt. t , time length Δt t One or more days; each day of period t is used as a small correction cycle, and each day has multiple periods t';

[0033] Step S4.1.2, for each day of time period t, determine the adjustable output of hydropower station l for each time period t' within the day

[0034] Specifically, the average output of hydropower station l in time period t obtained by the medium- and long-term complementary scheduling scheme of water, wind and solar power is As the average output of hydropower station l in each period t' of each day in period t, the average output of each period t' is deducted from the minimum technical output of the corresponding hydropower station in period t' to obtain the adjustable output of hydropower station l in each period t' within the day The formula is:

[0035]

[0036] in: is the minimum technical output of hydropower station l in time period t';

[0037] Step S4.1.3, for each day in time period t, determine the remaining transmission capacity of the transmission line in each time period t'

[0038] The maximum transmission capacity N of the transmission line in time period t' t' Or the output N of the transmission line required by the power grid in time period t' load,t' Based on the above, the short-term predicted output of wind and photovoltaic power stations in time period t' and the minimum technical output of hydropower stations in time period t' are deducted to obtain the remaining power transmission capacity of the power transmission line in each time period t' within the day. The formula is:

[0039]

[0040] or

[0041]

[0042] in:

[0043] If the dispatch target of the long-term and short-term nested correction model is to maximize the absorption rate of new energy, then select formula (6); if the dispatch target of the long-term and short-term nested correction model is to achieve the best matching between the source and the grid, then select formula (7);

[0044] Step S4.1.4, based on the power balance, the output of the hydropower station l in each period t' is corrected to obtain the output of the hydropower station l in the period t' after the correction based on the power balance.

[0045] Based on the adjustable output of the hydropower station at each time period t' within l day obtained in step S4.1.2 and the remaining transmission capacity of the transmission line in each time period t' obtained in step S4.1.3 The adjustable output within the day is reduced by using the method of load shedding The sum is redistributed to each period t' within the day, and the output of hydropower station l in period t' after correction based on power balance is obtained. The formula is: And satisfy in: is the adjustable output of hydropower station l in the daily period t'; a is the number of time periods t' included in a day, that is, a = 24 / Δt' t ; b is the number of days in the current period t';

[0046] Step S4.1.5: for each day of period t, repeat steps S4.1.2-S4.1.4 to obtain the output of each day of period t' after the power balance correction. That is, the output of hydropower station l in each time period t' within time period t

[0047] Step S4.1.6: Based on the water balance, the output of hydropower station l in each time period t' within time period t Further correction is made to obtain the output of hydropower station l in each time period t' within time period t after correction based on water balance, which is

[0048] Specifically, the hydropower output constraint repair strategy based on the final water level is adopted to correct the output of the hydropower station, including:

[0049] (1) Based on the output of hydropower station l at each time period t' in time period t obtained in step S4.1.5 The method of determining water level by electricity is used to calculate backwards for each period t' to obtain the final water level of the hydropower station l in period t

[0050] (2) Comparison of water levels and water level

[0051] like ε is the maximum allowable deviation of the water level, and the following method is used to correct the output of the hydropower station:

[0052] if Then reduce the output of hydropower station l in each period t' within period t Right now in, is the output correction of the hydropower station, obtained by trial calculation; based on the output of the hydropower station l in each time period t' within the time period t after correction The final water level of the hydropower station l in time period t is obtained by using the method of determining water level by electricity satisfy

[0053] if Then increase the output of hydropower station l in each period t' within period t Right now in, is the maximum allowable output of hydropower station l in time period t'; based on the corrected output of hydropower station l in time period t' The final water level of the hydropower station l in time period t is obtained by using the method of determining water level by electricity satisfy

[0054] if The output of the hydropower station is not corrected, and the output of the hydropower station l in each period t' within the period t is That is

[0055] Preferably, step S4.2 specifically includes:

[0056] Step S4.2.1, determine the abandoned power output of the integrated multi-energy complementary base of water, wind, solar and storage in the basin cascade at time period t'

[0057] Specifically, after the actual output of the hydropower station is superimposed on the short-term predicted output of the wind power station and the photovoltaic power station, the maximum transmission capacity N of the transmission line in the period t' is considered. t 'Or the output N of the transmission line required by the power grid in time period t' load,t' The restriction is obtained to obtain the abandoned power output of the integrated multi-energy complementary base of cascade water, wind, light and storage in the basin at time t' The formula is:

[0058]

[0059] or

[0060]

[0061] Step S4.2.2: According to the allocation principle, the abandoned power output of the integrated multi-energy complementary base of water, wind, solar and storage in the basin cascade is divided into Distributed to each wind power station and photovoltaic power station, the average output of each wind power station j in time period t' is obtained and the average output of each photovoltaic power station k in time period t' The formula is as follows:

[0062]

[0063] Where: α j and α k are the abandoned power allocation ratios of wind power station j and photovoltaic power station k, and satisfy

[0064] Furthermore, α j and α k Selection according to and The ratio is determined by

[0065]

[0066] Preferably, step S4.3 is specifically:

[0067] like It is determined that the pumped storage power station is in the pumped storage state; if If the transmission line has a surplus transmission capacity, the pumped storage power station is determined to be in a power generation state; the pumped storage power station determines its average output in time period t' according to certain operating principles and the generation strategy of the boundary of the pumped storage power station output feasible region

[0068] The operating characteristics of pumped storage power stations include:

[0069] The operating characteristics of pumped storage power plants need to consider the order of commissioning, operating principles and unit types of pumped storage power plants;

[0070] The order of operation is that the pumped-storage power station with the highest pumping and generating cycle efficiency is put into operation first, that is, pumping and storing water and power generation are given priority; if the pumping and generating cycle efficiencies of multiple pumped-storage power stations are the same, the pumped-storage power station with a larger maximum storage capacity is put into operation first; at the same time, the order in which the pumped-storage power stations are put into operation also needs to take into account the unit factors, especially for fixed-speed units;

[0071] There are two operating principles for pumped storage power stations: one is the principle of "pumping as much as possible" + "generating as much as possible", and the other is the principle of "pumping as much as possible" + "multi-day joint optimization of power generation";

[0072] The unit types include two types: one is a variable speed unit, which does not consider the full pumping requirement of a single unit of a pumped storage power station; the other is a fixed speed unit, which considers the full pumping requirement of a single unit of a pumped storage power station; the pumping power of the pumped storage power station unit does not consider the continuous value within a certain range when the single unit is fully pumped, which is any value that satisfies the maximum and minimum pumping power constraints of the pumped storage power station unit; the pumping power of the pumped storage power station unit can only take the maximum pumping power of the unit when the single unit is fully pumped; the output of the pumped storage power station is determined according to different combinations of the output conditions of each unit;

[0073] The output of a pumped-storage power station should consider the constraints of the installed capacity of the pumped-storage power station and the maintenance arrangement of the units, as well as the storage capacity constraints of the pumped-storage power station during the period and the storage capacity constraints at the beginning and end of the period. The strategy for generating the boundary of the feasible region of the output of the pumped-storage power station is used to determine the feasible range of the output of the pumped-storage power station, which specifically includes:

[0074] Step S4.3.1, the output process of the pumped storage power station and the energy storage process of the pumped storage power station satisfy the energy storage balance constraint equation of the pumped storage power station:

[0075]

[0076] in:

[0077] E m,t' is the storage capacity of the pumped storage power station m at the beginning of time period t'; and are the pumping power and generating power of the pumped storage power station m in time period t' respectively; and At least one of them has a value of 0 and specifies and are the pumping efficiency and power generation efficiency of the pumped storage power station m, respectively; E m,t'+1 is the storage capacity of the pumped storage power station m at the end of time period t'+1;

[0078] Step S4.3.2: If the basin cascade water-wind-solar-storage integrated multi-energy complementary base contains multiple pumped storage power stations, then execute steps S4.3.3-S4.3.7 for each pumped storage power station in sequence:

[0079] Step S4.3.3, determine the working status of the pumped storage power station m in time period t':

[0080] Specifically, according to the latest Determine whether the pumped storage power station m is in a pumped storage state or a power generation state;

[0081] Step S4.3.4, preliminarily generate the output feasible region boundary of pumped storage power station m in time period t' in, and They are the upper and lower limits of the output feasible region boundary of the pumped storage power station m in time period t':

[0082] If the pumped storage power station m is in the pumped storage state at time period t', the upper and lower limits of its output feasible region boundary at time period t' are determined according to formula (13):

[0083]

[0084] If the pumped storage power station m is in the power generation state at time period t', the upper and lower limits of its output feasible region boundary at time period t' are determined according to formula (14):

[0085]

[0086] in: and They are the maximum pumping power and maximum generating power of pumped-storage power station m in period t' after considering the installed capacity of the pumped-storage power station and the maintenance arrangement of the units; It is the remaining transmission capacity of the transmission line of the cascade hydro-wind-solar-storage integrated multi-energy complementary base in the basin at time period t', or the gap between the actual output of the transmission line and the transmission output required by the power grid;

[0087] Step S4.3.5, generate the storage capacity constraint boundary of pumped storage power station m in time period t' in, and are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m in time period t' respectively;

[0088] (1) For a pumped storage power station m, the initial storage capacity of the dispatch period is Based on the forward sequence calculation method, the energy storage constraint boundary in time period t' is generated using formula (15):

[0089]

[0090] For a pumped storage power station m, the storage capacity at the end of the dispatch period is Based on the reverse calculation method, formula (16) is used to generate the energy storage constraint boundary in time period t':

[0091]

[0092] in:

[0093] and They are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m at the end of period t'=0, i.e., the beginning of period t'=1, obtained by the forward sequence calculation method;

[0094] and are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m at the end of the time period t'=T' obtained by the reverse calculation method;

[0095] and are the storage capacity of pumped storage power station m at the beginning and end of the dispatch period respectively;

[0096] and are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m at the end of time period t' obtained by the forward sequence calculation method; and are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m at the end of time period t' obtained by the reverse calculation method;

[0097] and are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m at the end of time period t'-1 obtained by the forward sequence calculation method; and are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m at the end of time period t'+1 obtained by the reverse calculation method;

[0098] and E m are the maximum and minimum storage capacities of the pumped storage power station m, respectively;

[0099] (2) Using formula (17) to obtain the envelope, generate the storage capacity constraint boundary of the pumped storage power station m in time period t':

[0100]

[0101] in: and are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m in time period t' respectively;

[0102] Step S4.3.6, based on the storage capacity constraint boundary of the pumped storage power station m in time period t' obtained in step S4.3.5 As well as the energy balance constraint equation of the pumped storage power station in step S4.3.1, the output feasible region boundary of the pumped storage power station m in time period t' obtained in step S4.3.4 After correction, the output feasible region boundary of the pumped storage power station m in time period t' is obtained. in, and are the upper and lower limits of the output feasible region boundary of the modified pumped storage power station m in time period t';

[0103] Step S4.3.7, determine the actual output of the pumped-storage power station m in time period t' according to the upper and lower limits of the output feasible region boundary of the pumped-storage power station m in time period t' after correction According to the actual output of the pumped storage power station m in time period t' renew Then continue to determine the actual output of the next pumped storage power station in time period t'.

[0104] The method for simulating the operation of integrated scheduling of cascade water, wind, solar and storage in a watershed considering long-term and short-term nested correction provided by the present invention has the following advantages:

[0105] The present invention provides a basin cascade water, wind, solar and storage integrated scheduling and operation simulation method considering long-term and short-term nested correction. On the basis of medium- and long-term optimal scheduling, a long-term and short-term nested correction model is further constructed, which fully considers the random volatility of short-term wind and solar power output and the regulation capacity of short-term hydropower stations and pumped-storage power stations, so as to correct the actual output process of each power source in the basin cascade water, wind, solar and storage integrated multi-energy complementary base on a short-term scale, which is conducive to the effective acceptance of long-term consumption and short-term grid connection of the integrated multi-energy complementary base of water, wind, solar and storage under high proportion of new energy penetration, and meets the refined requirements of the multi-energy complementary scheduling system for evaluating indicators such as new energy absorption rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0106] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the related technologies, the following briefly introduces the drawings required for use in the embodiments or the related technologies. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0107] Figure 1 A schematic diagram of the overall process of a basin cascade water-wind-solar-storage integrated scheduling and operation simulation method considering long-term and short-term nested correction provided by the present invention;

[0108] Figure 2 This is a result diagram of a medium- and long-term scale water-wind-solar electricity complementary scheduling scheme obtained by optimizing a basin-level integrated medium- and long-term optimization scheduling model for water, wind, solar, and storage in one embodiment of the present invention;

[0109] Figure 3 It is a flow chart of a long-short term nested correction model for fine correction of each power output process in one embodiment of the present invention;

[0110] Figure 4 A flow chart of determining the average output of a hydropower station in time period t' using a long-short term nested correction model in one embodiment of the present invention;

[0111] Figure 5 A flow chart of determining the average output of a wind power station in time period t' and the average output of a photovoltaic power station in time period t' by a long-short term nested correction model in one embodiment of the present invention;

[0112] Figure 6 A flow chart of determining the average output of a pumped storage power station in time period t' using a long-short term nested correction model in one embodiment of the present invention;

[0113] Figure 7This is a result diagram of a short-term scale electricity complementary scheduling scheme for water, wind, solar and storage obtained by using a basin cascade water, wind, solar and storage integrated scheduling operation simulation method based on a long-short term nested correction strategy in one embodiment of the present invention. DETAILED DESCRIPTION

[0114] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work should fall within the scope of protection of the present application.

[0115] The terms used herein are only for describing the specific embodiments of the present invention, and are not intended to limit the present application. The terms "comprise", "include", etc. used herein indicate the existence of the features, steps and / or operations, but do not exclude the existence or addition of one or more other features, steps or operations.

[0116] All terms (including technical terms and scientific terms) used herein have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein have the meanings consistent with the context of the corresponding terms in the claims and the specification of this application, and should not be understood in an idealized or overly rigid manner.

[0117] The technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems are described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0118] The present invention provides a basin cascade water, wind, solar and storage integrated scheduling and operation simulation method considering long-term and short-term nested correction, further constructs a long-term and short-term nested correction model on the basis of medium- and long-term optimal scheduling, comprehensively considers the medium- and long-term electricity compensation and short-term electricity compensation of the basin cascade water, wind, solar and storage integrated multi-energy complementary base, fully considers the random volatility of short-term wind and solar output, and the regulation capacity of short-term hydropower stations and pumped-storage power stations, so as to correct the actual output process of each power source in the basin cascade water, wind, solar and storage integrated multi-energy complementary base on a short-term scale, which is conducive to the effective acceptance of long-term consumption and short-term grid connection of the water, wind, solar and storage integrated multi-energy complementary base under high proportion of new energy penetration, and meets the refined requirements of the multi-energy complementary scheduling system for evaluating indicators such as new energy absorption rate. At the same time, the long-short term nested correction model of the present invention simultaneously considers the regulating role of the pumped-storage power station, including the order of commissioning, operating principles, unit types and output constraints of the pumped-storage power station, and provides a strategy for generating the boundary of the feasible domain of the pumped-storage power station output, which is used to guide the optimization of the output process of the pumped-storage power station, thereby further improving the universality of the integrated scheduling and operation simulation method and the operating efficiency of the integrated multi-energy complementary base, and scientifically guiding the scheduling and operation of the integrated multi-energy complementary base of cascade water, wind, light and storage in the basin.

[0119] See also Figure 1 The present invention provides a basin cascade water, wind, solar and storage integrated scheduling and operation simulation method considering long-term and short-term nested correction, comprising the following steps:

[0120] Step S1: Taking the maximum power generation or maximum power generation benefit of the integrated multi-energy complementary base of cascade water, wind, solar and storage in the basin as the scheduling target, comprehensively considering the constraints of various power sources and transmission lines, and constructing a medium- and long-term optimal scheduling model for the integrated multi-energy complementary base of cascade water, wind, solar and storage in the basin;

[0121] Step S2: Solve the medium- and long-term optimal dispatch model of the integrated water, wind, solar and storage cascade in the basin to obtain the medium- and long-term scale complementary dispatch plan of water, wind and solar;

[0122] Step S3: Taking the maximum new energy absorption rate or the best source-grid matching of the integrated multi-energy complementary base of water, wind, solar and storage in the basin as the scheduling target, a long-short-term nested correction model is constructed;

[0123] Step S4: Based on the long-short term nested correction model, the output process of each power source of the cascade water-wind-solar-storage integrated multi-energy complementary base in the basin is refined to obtain a short-term scale power complementary dispatching plan for water-wind-solar-storage to guide the dispatching and operation of the cascade water-wind-solar-storage integrated multi-energy complementary base in the basin.

[0124] The following is a detailed explanation of the steps of a basin cascade water, wind, solar and storage integrated scheduling and operation simulation method considering long-term and short-term nested correction provided by the present invention:

[0125] Step S1: Taking the maximum power generation or maximum power generation benefit of the integrated multi-energy complementary base of cascade water, wind, solar and storage in the basin as the scheduling target, comprehensively considering the constraints of various power sources and transmission lines, and constructing a medium- and long-term optimal scheduling model for the integrated multi-energy complementary base of cascade water, wind, solar and storage in the basin;

[0126] In this step, the medium- and long-term optimal scheduling model of the integrated cascade water, wind, solar and storage in the river basin should meet the constraints of each power source and transmission line; the constraints of each power source and transmission line include but are not limited to hydraulic connections between cascade hydropower stations, water balance constraints of hydropower stations, upper and lower limits and amplitude constraints of water levels of hydropower stations, water level constraints at the beginning and end of the scheduling period of hydropower stations, outflow constraints of hydropower stations, output constraints of hydropower stations, head constraints of hydropower stations, output constraints of wind power stations, output constraints of photovoltaic power stations and output constraints of transmission lines.

[0127] The output constraint of the transmission line mainly considers the maximum transmission capacity of the transmission line, specifically, the output of the transmission line meets the TTC limit of the transmission line, which is expressed as: P t <N t ; Among them: P t is the actual output of the transmission line in time period t, which is also the total output of the integrated multi-energy complementary base in time period t; N t is the TTC limit of the transmission line in time period t.

[0128] Taking into account that the current regulation capacity of pumped-storage power stations is mostly based on daily and weekly basis, the power supply configuration of the basin-wide cascade water-wind-solar-storage integrated medium- and long-term optimization scheduling model mainly considers the combination of hydropower stations, wind power stations and photovoltaic power stations, while pumped-storage power stations are considered in the long- and short-term nested correction model.

[0129] As a specific embodiment, the expression of the scheduling target F1 with the maximum power generation is:

[0130]

[0131] Where: t is the time period number used in the medium- and long-term optimization scheduling model of the integrated water, wind, solar and storage cascade in the basin; Δt t is the length of time period t; T is the number of time periods t included in the scheduling period; N w 、N s and N h They are the number of wind power stations, photovoltaic power stations and hydropower stations participating in the dispatching and operation of the cascade water-wind-solar-storage integrated multi-energy complementary base in the basin; and are the average outputs of wind power station j, photovoltaic power station k and hydropower station l in time period t; j = 1, 2, ..., N w ; k = 1, 2, ..., N s ; l=1,2,...,N h ;

[0132] The expression of the dispatching target F2 with the maximum power generation benefit is:

[0133]

[0134] in: and are the power generation benefits of wind power station j, photovoltaic power station k and hydropower station l in time period t respectively; and are the on-grid electricity prices of wind power station j, photovoltaic power station k and hydropower station l in time period t. Under the principle of “same grid, same quality, same price”,

[0135] Step S2: Solve the medium- and long-term optimal dispatch model of the integrated water, wind, solar and storage cascade in the basin to obtain the medium- and long-term scale complementary dispatch plan of water, wind and solar;

[0136] This step is specifically as follows: solve the medium- and long-term optimization scheduling model of the integrated cascade water, wind, solar and storage in the basin, and obtain the optimal medium- and long-term operation mode of each power source such as hydropower station, wind power station, photovoltaic power station, etc. that meets the scheduling objectives and constraints, including but not limited to: the average output of each hydropower station, wind power station, photovoltaic power station and other power sources in each time period t during the scheduling period, the water level of each hydropower station in each time period t, etc.; among which, for hydropower station l, its average output in time period t is expressed as The water level at the end of time period t is expressed as

[0137] It should be noted that in this step, the optimal medium- and long-term operation mode of the power source solved does not include pumped storage power stations.

[0138] In this step, the solution method for the medium- and long-term optimization scheduling model of the integrated cascade water, wind, solar and storage in the basin can be a swarm intelligence optimization algorithm, including but not limited to the improved bee colony algorithm, the dynamically adjusted particle swarm algorithm, etc. When the algorithm is optimized, the water level of each hydropower station reservoir is used as the decision variable, and the output of the wind and solar power station is regarded as a constant value during the optimization process. The optimal medium- and long-term operation mode of each power source other than the pumped storage power station that meets the scheduling objectives and all constraints is solved, and the medium- and long-term scale electricity complementary scheduling plan of the integrated multi-energy complementary base water, wind and solar is obtained.

[0139] In an exemplary embodiment, the basin cascade water, wind, solar and storage integrated multi-energy complementary base includes three cascade hydropower stations (i.e., N h =3, with a total installed capacity of 5 million kW), 2 wind power stations (i.e. N w =2, with a total installed capacity of 3 million kW), 12 photovoltaic power stations (i.e. N s = 12, with a total installed capacity of 1110 kW) and two pumped storage power stations (i.e. N st=2, total installed capacity 3 million kW), the TTC limit of the transmission line is 8 million kW. Among them, the pumped storage power station is considered in the long-term and short-term nested correction model. Taking the maximum power generation of the basin cascade water, wind, light and storage integrated multi-energy complementary base as the dispatch target and the week as the dispatch period, the integrated multi-energy complementary base water, wind and light medium- and long-term scale electricity complementary dispatching scheme obtained by the basin cascade water, wind, light and storage integrated medium- and long-term optimization dispatching model is as follows Figure 2 shown.

[0140] Since the mid- and long-term optimization dispatching model of the integrated water, wind, solar and storage in the basin does not take into account the random volatility of short-term wind and solar output and the regulation capacity of short-term hydropower stations and pumped storage power stations, it is not conducive to the effective acceptance of long-term consumption and short-term grid connection of the integrated multi-energy complementary base of water, wind, solar and storage under the high proportion of new energy penetration. Therefore, step S3 is further used to construct a long- and short-term nested correction model, comprehensively consider the above factors, and more accurately evaluate the various dispatching and operation indicators of the integrated multi-energy complementary base of water, wind, solar and storage in the basin.

[0141] Step S3: Taking the maximum new energy absorption rate or the best source-grid matching of the integrated multi-energy complementary base of water, wind, solar and storage in the basin as the scheduling target, a long-short-term nested correction model is constructed;

[0142] This step is specifically as follows: taking the maximum new energy absorption rate or the best source-grid matching of the basin cascade water, wind, solar and storage integrated multi-energy complementary base as the dispatching target, and solving the average output of the hydropower station l in time period t based on the medium- and long-term optimal dispatching model of the basin cascade water, wind, solar and storage integrated multi-energy complementary base. And the predicted output of wind power station j in each time period t' during the dispatch period And the output of photovoltaic power station k in each time period t' during the dispatch period Taking into account the TTC restrictions of transmission lines or grid requirements, the characteristics of hydropower stations and pumped storage power stations, a long-short-term nested correction model is constructed; where t' is the time period number used in the long-short-term nested correction model.

[0143] As a specific embodiment, the medium- and long-term scale adopted by the medium- and long-term optimization scheduling model for the integrated water, wind, solar and storage cascade in the basin can be day / month / ten-day period / week, so the time length of each scheduling period t is month / ten-day period / week; the short-term scale adopted by the long- and short-term nested correction model can be hour / 30min / 15min, so the time length of each scheduling period t' is hour / 30min / 15min.

[0144] Correspondingly, the average output of hydropower station l in time period t obtained by solving the medium- and long-term optimal scheduling model of cascade water, wind, solar and storage integration in the basin is is the daily / monthly / ten-day / weekly average output; the predicted output of wind power station j in each time period t' during the dispatch period And the output of photovoltaic power station k in each time period t' during the dispatch period The output is hour / 30min / 15min, which is the same as the short-term scale of the long-short term nested correction model.

[0145] As a specific embodiment, the expression of the dispatching target F3 with the maximum new energy absorption rate of the integrated multi-energy complementary base of water, wind, light and storage in the basin cascade is:

[0146]

[0147] Where: Δt′ t is the length of time period t', Δt' t Less than Δt t ; T' is the number of time periods t' included in the scheduling period; N st The number of all pumped-storage power stations participating in the dispatching and operation of the cascade water, wind, solar and storage integrated multi-energy complementary base in the basin; and are the average outputs of wind power station j, photovoltaic power station k, hydropower station l and pumped storage power station m in time period t'; Pd st The power generation corresponding to the difference in storage capacity between the beginning and the end of the dispatch period of the pumped storage power station;

[0148] The expression of the dispatching target F4 with the best source-grid matching of the integrated multi-energy complementary base of water, wind, solar and storage in the basin is:

[0149]

[0150] Among them: PR t' is the residual load of the power grid in time period t', that is, the output N of the power transmission line required by the power grid in time period t' load,t' The actual output P of the transmission line in time period t' t' The difference, PR t' =N load,t' -P t' ; is the average grid residual load during the dispatch period, that is,

[0151] Step S4: Based on the long-short term nested correction model, the output process of each power source of the cascade water-wind-solar-storage integrated multi-energy complementary base in the basin is refined to obtain a short-term scale power complementary dispatching plan for water-wind-solar-storage to guide the dispatching and operation of the cascade water-wind-solar-storage integrated multi-energy complementary base in the basin.

[0152] In an exemplary embodiment, the process of correcting the output process of each power source by the long-short term nested correction model is as follows: Figure 3 As shown, including:

[0153] Step S4.1, using the long-short term nested correction model, determine the average output of hydropower station l in period t'

[0154] Step S4.2, using the long-short term nested correction model, determine the average output of wind power station j in period t' and the average output of photovoltaic power station k in time period t'

[0155] Step S4.3, using the long-short term nested correction model, determine the average output of the pumped storage power station m in period t'

[0156] Step S4.4, the average output of hydropower station l in time period t' obtained according to steps S4.1, S4.2 and S4.3 The average output of wind power station j in period t' Average output of photovoltaic power station k in time period t' and the average output of pumped storage power station m in period t' Re-evaluate indicators such as the new energy absorption rate of the integrated multi-energy complementary base of water, wind, solar and storage in the basin and the utilization hours of transmission lines.

[0157] The specific implementation process of steps S4.1 to S4.4 is as follows:

[0158] Step S4.1, using the long-short term nested correction model, determine the average output of hydropower station l in period t'

[0159] It should be noted that the calculation order of cascade hydropower stations is that the upstream hydropower station takes priority, and the downstream hydropower station takes the latter. This principle is also adopted in the following steps.

[0160] See also Figure 4 , step S4.1 specifically includes:

[0161] Step S4.1.1: The time length of the period t used in the medium- and long-term optimization scheduling model of the integrated water, wind, solar and storage cascade in the basin is Δt. t , Δt t It can be day / month / ten-day / week, so the time length Δt t One or more days; each day of time period t is used as a small correction cycle, and each day has multiple time periods t'; time period t' can be hours / 30 minutes / 15 minutes;

[0162] Step S4.1.2, for each day of time period t, determine the adjustable output of hydropower station l for each time period t' within the day

[0163] Specifically, the average output of hydropower station l in time period t obtained by the medium- and long-term complementary scheduling scheme of water, wind and solar power is As the average output of hydropower station l in each period t' of each day in period t, the average output of each period t' is deducted from the minimum technical output of the corresponding hydropower station in period t' to obtain the adjustable output of hydropower station l in each period t' within the day The formula is:

[0164]

[0165] in: is the minimum technical output of hydropower station l in period t';

[0166] Step S4.1.3, for each day in time period t, determine the remaining transmission capacity of the transmission line in each time period t'

[0167] The maximum transmission capacity N of the transmission line in time period t' t' Or the output N of the transmission line required by the power grid in time period t' load,t' Based on the above, the short-term predicted output of wind and photovoltaic power stations in time period t' and the minimum technical output of hydropower stations in time period t' are deducted to obtain the remaining power transmission capacity of the power transmission line in each time period t' within the day. The formula is:

[0168]

[0169] or

[0170]

[0171] in:

[0172] If the dispatch target of the long-term and short-term nested correction model is to maximize the absorption rate of new energy, then select formula (6); if the dispatch target of the long-term and short-term nested correction model is to achieve the best matching between the source and the grid, then select formula (7);

[0173] Step S4.1.4, based on the power balance, the output of the hydropower station l in each period t' is corrected to obtain the output of the hydropower station l in the period t' after the correction based on the power balance.

[0174] Based on the adjustable output of the hydropower station at each time period t' within l day obtained in step S4.1.2 and the remaining transmission capacity of the transmission line in each time period t' obtained in step S4.1.3 The adjustable output within the day is reduced by using the method of load shedding The sum is redistributed to each period t' within the day, and the output of hydropower station l in period t' after correction based on power balance is obtained. The formula is: And satisfy in: is the adjustable output of hydropower station l in the daily period t'; a is the number of time periods t' included in a day, that is, a = 24 / Δt' t ; b is the number of days in the current period t'; for example, if the scheduling period t' of the long-short-term nested correction model is hours, then a=24; if the scheduling period t' of the long-short-term nested correction model is 15 minutes, then a=96.

[0175] Step S4.1.5: for each day of period t, repeat steps S4.1.2-S4.1.4 to obtain the output of each day of period t' after the power balance correction. That is, the output of hydropower station l in each time period t' within time period t

[0176] Step S4.1.6: Based on the water balance, the output of hydropower station l in each time period t' within time period t Further correction is made to obtain the output of hydropower station l in each time period t' within time period t after correction based on water balance, which is

[0177] Specifically, the hydropower output constraint repair strategy based on the final water level is adopted to correct the output of the hydropower station, including:

[0178] (1) Based on the output of hydropower station l at each time period t' in time period t obtained in step S4.1.5 Using the refined method of determining water level by electricity, we calculate backwards for each period t' to obtain the final water level of the hydropower station l in period t

[0179] therefore, is the final water level of the medium- and long-term scheduling period t obtained by the long- and short-term nested correction model; and in the aforementioned step S2, the final water level of the medium- and long-term scheduling period t is obtained by using the basin cascade water, wind, solar and storage integrated medium- and long-term optimization scheduling model By comparing the water level and water level The deviation can be used to realize the repair of hydropower output constraint based on the final water level.

[0180] (2) Comparison of water levels and water level

[0181] like ε is the maximum allowable deviation of the water level, and the output of the hydropower station is corrected in the following way:

[0182] if Then reduce the output of hydropower station l in each period t' within period t Right now in, is the output correction of the hydropower station, obtained by trial calculation; based on the output of the hydropower station l in each time period t' within the time period t after correction The final water level of the hydropower station l in time period t is obtained by using the method of determining water level by electricity satisfy

[0183] if Then increase the output of hydropower station l in each period t' within period t Right now in, is the maximum allowable output of hydropower station l in time period t'; based on the corrected output of hydropower station l in time period t' The final water level of the hydropower station l in time period t is obtained by using the method of determining water level by electricity satisfy

[0184] if The output of the hydropower station is not corrected, and the output of the hydropower station l in each period t' within the period t is That is

[0185] Step S4.2, using the long-short term nested correction model, determine the average output of wind power station j in period t' and the average output of photovoltaic power station k in time period t'

[0186] See also Figure 5 , step S4.2 specifically includes:

[0187] Step S4.2.1, determine the abandoned power output of the integrated multi-energy complementary base of water, wind, solar and storage in the basin cascade at time period t'

[0188] Specifically, after the actual output of the hydropower station is superimposed on the short-term predicted output of the wind power station and the photovoltaic power station, the maximum transmission capacity N of the transmission line in the period t' is considered. t' Or the output N of the transmission line required by the power grid in time period t' load,t' The restriction is obtained to obtain the abandoned power output of the integrated multi-energy complementary base of cascade water, wind, light and storage in the basin at time t' The formula is:

[0189]

[0190] or

[0191]

[0192] Step S4.2.2: According to certain allocation principles, the abandoned power output of the integrated multi-energy complementary base of water, wind, solar and storage in the basin cascade is allocated in time period t'. Distributed to each wind power station and photovoltaic power station, the average output of each wind power station j in time period t' is obtained and the average output of each photovoltaic power station k in time period t' The formula is as follows:

[0193]

[0194] Where: α j and α k are the abandoned power allocation ratios of wind power station j and photovoltaic power station k, and satisfy

[0195] Furthermore, α j and α k The selection can be based on and The ratio is determined by At the same time, α j and α k The selection may also be determined by considering other factors.

[0196] Step S4.3, using the long-short term nested correction model, determine the average output of the pumped storage power station m in period t'

[0197] Step S4.3 is specifically as follows:

[0198] like It is determined that the pumped storage power station is in the pumped storage state; if If the transmission line has a surplus transmission capacity, the pumped storage power station is determined to be in a power generation state; the pumped storage power station determines its average output in time period t' according to certain operating principles and the generation strategy of the boundary of the pumped storage power station output feasible region

[0199] The operating characteristics of pumped storage power stations include:

[0200] The long-short term nested correction model takes into account the regulation capacity of the pumped storage power station, so the order of commissioning, operating principles, unit types, etc. of the pumped storage power station must be considered. Therefore, the operating characteristics of the pumped storage power station include the order of commissioning, operating principles, and unit types of the pumped storage power station;

[0201] If the basin cascade water, wind, solar and storage integrated multi-energy complementary base contains multiple pumped storage power stations, the order in which the pumped storage power stations are put into operation needs to be considered. Specifically, the order of operation is that the pumped storage power station with the highest pumping and generation cycle efficiency is put into operation first, that is, priority is given to pumping and storage and priority is given to power generation; if the pumping and generation cycle efficiencies of multiple pumped storage power stations are the same, the pumped storage power station with the larger maximum storage capacity is put into operation first; at the same time, the order in which the pumped storage power stations are put into operation also needs to consider the unit factors, especially for fixed-speed units;

[0202] The long-short term nested correction model considers two operating principles of pumped storage power stations: one is the principle of "pumping as much as possible" + "generating as much as possible", and the other is the principle of "pumping as much as possible" + "multi-day joint optimization of power generation";

[0203] The principle of "extracting as much as possible" means that there is abandoned power (i.e. ) When there is still a storage capacity gap in the pumped storage power station, use the pumped storage power station as much as possible to absorb the abandoned electricity;

[0204] The principle of "generating as much as possible" means that when there is surplus transmission capacity in the transmission lines of the integrated multi-energy complementary base of water, wind, solar and storage in the basin, or there is a gap between the actual output of the transmission lines and the transmission curve required by the power grid, and the pumped-storage power station still has available storage capacity, the pumped-storage power station should be used as much as possible to make up for the surplus transmission capacity or the gap between the actual output and the required transmission curve;

[0205] The principle of "multi-day joint optimization of power generation" means comprehensively considering the short-term output characteristics of wind and solar power stations in the next one or more days, optimizing the output process of pumped storage power stations, and making the power transmission curve of the integrated multi-energy complementary base of water, wind, solar and storage in the basin more consistent with the power transmission curve required by the grid end;

[0206] As an example, the principle of "extracting as much as possible" + "generating as much as possible" is applicable to the basin cascade water, wind, solar and storage integrated multi-energy complementary base with the maximum new energy absorption rate as the scheduling target;

[0207] As an example, the principle of "extracting as much as possible" + "multi-day joint optimization of power generation" is applicable to the basin cascade water, wind, solar and storage integrated multi-energy complementary base with the best source-grid matching as the scheduling target;

[0208] The long-short term nested correction model considers two types of pumped storage units: one is a variable speed unit, which does not consider the full pumping requirement of a single unit of a pumped storage power station; the other is a fixed speed unit, which considers the full pumping requirement of a single unit of a pumped storage power station; the pumping power of the pumped storage power station unit is not considered to be continuous within a certain range when the single unit is fully pumped, and can be any value that satisfies the maximum and minimum pumping power constraints of the pumped storage power station unit; the pumping power of the pumped storage power station unit can only take the maximum pumping power of the unit when the single unit is fully pumped; the output of the pumped storage power station is determined according to different combinations of the output conditions of each unit;

[0209] The output of a pumped-storage power station must take into account the constraints of the installed capacity of the pumped-storage power station and the maintenance arrangement of the units, as well as the storage capacity constraints of the pumped-storage power station during the period and the storage capacity constraints at the beginning and end of the period. The present invention proposes a strategy for generating the boundary of the feasible region of the output of a pumped-storage power station, which is used to determine the feasible range of the output of a pumped-storage power station. In an exemplary embodiment, Figure 6 As shown in Figure 2, the specific steps of the strategy for generating the boundary of the feasible region of the pumped storage power station output include:

[0210] Step S4.3.1, the output process of the pumped storage power station and the energy storage process of the pumped storage power station satisfy the energy storage balance constraint equation of the pumped storage power station:

[0211]

[0212] in:

[0213] E m,t' is the storage capacity of the pumped storage power station m at the beginning of time period t'; and are the pumping power and generating power of the pumped storage power station m in time period t' respectively; and At least one of them has a value of 0 and specifies and are the pumping efficiency and power generation efficiency of the pumped storage power station m, respectively; E m,t'+1 is the storage capacity of the pumped storage power station m at the end of time period t'+1;

[0214] Step S4.3.2: If the basin cascade water-wind-solar-storage integrated multi-energy complementary base contains multiple pumped storage power stations, then execute steps S4.3.3-S4.3.7 for each pumped storage power station in sequence:

[0215] Step S4.3.3, determine the working status of the pumped storage power station m in time period t':

[0216] Specifically, according to the latest Determine whether the pumped storage power station m is in the pumped storage state or the power generation state; it should be noted that if the basin cascade water-wind-solar-storage integrated multi-energy complementary base contains multiple pumped storage power stations, when determining the working state of the next pumped storage power station, it is necessary to consider the impact of the pumped storage power station that has been put into operation and re-update

[0217] Step S4.3.4, preliminarily generate the output feasible region boundary of pumped storage power station m in time period t' in, and They are the upper and lower limits of the output feasible region boundary of the pumped storage power station m in time period t':

[0218] If the pumped storage power station m is in the pumped storage state at time period t', the upper and lower limits of its output feasible region boundary at time period t' are determined according to formula (13):

[0219]

[0220] If the pumped storage power station m is in the power generation state at time period t', the upper and lower limits of its output feasible region boundary at time period t' are determined according to formula (14):

[0221]

[0222] in: and They are the maximum pumping power and maximum generating power of pumped-storage power station m in period t' after considering the installed capacity of the pumped-storage power station and the maintenance arrangement of the units; It is the remaining transmission capacity of the transmission line of the cascade hydro-wind-solar-storage integrated multi-energy complementary base in the basin at time period t', or the gap between the actual output of the transmission line and the transmission output required by the power grid;

[0223] Step S4.3.5, generate the storage capacity constraint boundary of pumped storage power station m in time period t' in, and are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m in time period t' respectively;

[0224] (1) For a pumped storage power station m, the initial storage capacity of the dispatch period is Based on the forward sequence calculation method, the energy storage constraint boundary in time period t' is generated using formula (15):

[0225]

[0226] For a pumped storage power station m, the storage capacity at the end of the dispatch period is Based on the reverse calculation method, formula (16) is used to generate the energy storage constraint boundary in time period t':

[0227]

[0228] in:

[0229] and They are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m at the end of period t'=0, i.e., the beginning of period t'=1, obtained by the forward sequence calculation method;

[0230] and are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m at the end of the time period t'=T' obtained by the reverse calculation method;

[0231] and are the storage capacity of pumped storage power station m at the beginning and end of the dispatch period respectively;

[0232] and are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m at the end of time period t' obtained by the forward sequence calculation method; and are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m at the end of time period t' obtained by the reverse calculation method;

[0233] and are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m at the end of time period t'-1 obtained by the forward sequence calculation method; and are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m at the end of time period t'+1 obtained by the reverse calculation method;

[0234] and E m are the maximum and minimum storage capacities of the pumped storage power station m, respectively;

[0235] Generally speaking, the maximum storage capacity of a pumped-storage power station is equal to the installed capacity of the pumped-storage power station multiplied by the number of hours of full utilization of the power station divided by the power generation efficiency, and the minimum storage capacity of a pumped-storage power station is equal to 0.

[0236] (2) Using formula (17) to obtain the envelope, generate the storage capacity constraint boundary of the pumped storage power station m in time period t':

[0237]

[0238] in: and are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m in time period t' respectively;

[0239] Step S4.3.6, based on the storage capacity constraint boundary of the pumped storage power station m in time period t' obtained in step S4.3.5 As well as the energy balance constraint equation of the pumped storage power station in step S4.3.1, the output feasible region boundary of the pumped storage power station m in time period t' obtained in step S4.3.4 After correction, the output feasible region boundary of the pumped storage power station m in time period t' is obtained. in, and are the upper and lower limits of the output feasible region boundary of the modified pumped storage power station m in time period t';

[0240] It should be noted that if there is no clear requirement for the storage capacity of the pumped storage power station at the end of the dispatch period during the dispatch operation, then the formula (16)

[0241] It should be noted that if the unit type of the pumped-storage power station is a fixed-speed unit, it needs to be further determined based on different combinations of the feasible domain boundary of the pumped-storage power station output and the single-unit capacity of the pumped-storage power station units.

[0242] Step S4.3.7, determine the actual output of the pumped-storage power station m in time period t' according to the upper and lower limits of the output feasible region boundary of the pumped-storage power station m in time period t' after correction According to the actual output of the pumped storage power station m in time period t' renew Then continue to determine the actual output of the next pumped storage power station in time period t'.

[0243] Step S4.4, the average output of hydropower station l in time period t' obtained according to steps S4.1, S4.2 and S4.3 The average output of wind power station j in period t' Average output of photovoltaic power station k in time period t' and the average output of pumped storage power station m in period t' Re-evaluate indicators such as the new energy absorption rate of the integrated multi-energy complementary base of water, wind, solar and storage in the basin and the utilization hours of transmission lines.

[0244] In an exemplary embodiment:

[0245] The medium- and long-term optimal dispatching model for the integration of water, wind, solar and storage in the basin cascade takes the week as the medium- and long-term dispatching period, that is, the medium- and long-term dispatching period t is a week. By solving the medium- and long-term optimal dispatching model for the integration of water, wind, solar and storage in the basin cascade, the medium- and long-term scale complementary dispatching plan of water, wind and solar is obtained as follows: the average output of each hydropower station, wind power station and photovoltaic power station on a weekly basis, and the final water level of each hydropower station on a weekly basis;

[0246] The short-term scale used by the long-term and short-term nested correction model is hours, that is, the short-term scheduling period t' is hours; therefore, the hourly predicted output of wind power stations and photovoltaic power stations under the short-term scale are obtained; the medium- and long-term scale electricity complementary scheduling of water, wind, and photovoltaic power obtained by solving the medium- and long-term optimal scheduling model of the cascade water, wind, and photovoltaic storage integration in the basin is combined, and the TTC restrictions of the transmission lines or the requirements of the power grid, the characteristics of the hydropower station and the pumped storage power station are comprehensively considered to construct a long-term and short-term nested correction model;

[0247] By adopting the long-term and short-term nested correction model, the hourly average output of hydropower stations, wind power stations, photovoltaic power stations and pumped storage power stations can be determined respectively within a week, and the short-term scale power complementary dispatching scheme of water, wind, photovoltaic and storage can be obtained. As an example, the integrated multi-energy complementary dispatching scheme of water, wind, photovoltaic and storage for the integrated multi-energy complementary base is obtained by considering the long-term and short-term nested correction basin cascade water, wind, photovoltaic and storage integrated dispatching operation simulation method. Figure 7 As shown, Figure 7 The average output and abandoned power output of hydropower stations, wind power stations, photovoltaic power stations and pumped storage power stations are shown for each hour of the 168 hours in a week; the abandoned power output includes wind power abandonment and photovoltaic power abandonment.

[0248] The basin-wide cascade water, wind, solar and storage integrated scheduling and operation simulation method based on the long-term and short-term nested correction strategy proposed in the present invention realizes the medium- and long-term scale electricity compensation and short-term electricity compensation of the basin-wide cascade water, wind, solar and storage integrated multi-energy complementary base, and realizes the effective acceptance of long-term consumption and short-term grid connection of the water, wind, solar and storage integrated multi-energy complementary base under high proportion of new energy penetration; the long-term and short-term nested correction model fully considers the commissioning sequence, operation principles, unit types, etc. of pumped-storage power stations, and provides a strategy for generating the boundary of the feasible domain of the output of pumped-storage power stations, which is used to guide the optimization of the output process of pumped-storage power stations, and further improve the universality of the integrated scheduling and operation simulation method and the operating efficiency of the integrated multi-energy complementary base.

[0249] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0250] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A basin cascade water, wind, solar and storage integrated scheduling and operation simulation method considering long-term and short-term nested correction, characterized in that: The following steps are involved: Step S1: Taking the maximum power generation or maximum power generation benefit of the integrated multi-energy complementary base of cascade water, wind, solar and storage in the basin as the scheduling target, comprehensively considering the constraints of various power sources and transmission lines, and constructing a medium- and long-term optimal scheduling model for the integrated multi-energy complementary base of cascade water, wind, solar and storage in the basin; Step S2: Solve the medium- and long-term optimal dispatch model of the integrated water, wind, solar and storage cascade in the basin to obtain the medium- and long-term scale complementary dispatch plan of water, wind and solar; Step S3: Taking the maximum new energy absorption rate or the best source-grid matching of the integrated multi-energy complementary base of water, wind, solar and storage in the basin as the scheduling target, a long-short-term nested correction model is constructed; Step S4: Based on the long-short term nested correction model, the output process of each power source of the cascade water-wind-solar-storage integrated multi-energy complementary base in the basin is refined and corrected to obtain a short-term scale power complementary dispatching plan for water-wind-solar-storage to guide the dispatching and operation of the cascade water-wind-solar-storage integrated multi-energy complementary base in the basin; Step S4 specifically includes: Step S4.1, using the long-short term nested correction model, determine the average output of hydropower station l in period t' Step S4.2: Use the long-short term nested correction model to determine the average output of wind power station j in period t' and the average output of photovoltaic power station k in time period t' Step S4.2 specifically includes: Step S4.2.1, determine the abandoned power output of the integrated multi-energy complementary base of water, wind, solar and storage in the basin cascade at time period t' Specifically, after the actual output of the hydropower station is superimposed on the short-term predicted output of the wind power station and the photovoltaic power station, the maximum transmission capacity N of the transmission line in the period t' is considered. t' Or the output N of the transmission line required by the power grid in time period t' load,t' The power output of the integrated multi-energy complementary base of cascade water, wind, solar and storage in the basin at time t' is obtained. The formula is: or Step S4.2.2: According to the allocation principle, the abandoned power output of the integrated multi-energy complementary base of water, wind, solar and storage in the basin cascade is divided into Distributed to each wind power station and photovoltaic power station, the average output of each wind power station j in time period t' is obtained and the average output of each photovoltaic power station k in time period t' The formula is as follows: Where: α j and α k are the abandoned power allocation ratios of wind power station j and photovoltaic power station k, and satisfy Furthermore, α j and α k Selection according to and The ratio is determined by Step S4.3, using the long-short term nested correction model, determine the average output of the pumped storage power station m in period t' Step S4.4, the average output of hydropower station l in time period t' obtained according to steps S4.1, S4.2 and S4.3 The average output of wind power station j in period t' Average output of photovoltaic power station k in time period t' and the average output of pumped storage power station m in period t' Re-evaluate the new energy absorption rate and transmission line utilization hours indicators of the basin's cascade integrated multi-energy complementary base of water, wind, solar and storage.

2. A basin cascade water, wind, solar and storage integrated scheduling and operation simulation method considering long-term and short-term nested correction according to claim 1, characterized in that: In step S1, the constraints of each power source and transmission line include hydraulic connection of cascade hydropower stations, water balance constraints of hydropower stations, upper and lower limits and amplitude constraints of water levels of hydropower stations, water level constraints at the beginning and end of the dispatching period of hydropower stations, outflow constraints of hydropower stations, output constraints of hydropower stations, head constraints of hydropower stations, output constraints of wind power stations, output constraints of photovoltaic power stations and output constraints of transmission lines.

3. A basin cascade water, wind, solar and storage integrated scheduling and operation simulation method considering long-term and short-term nested correction according to claim 1, characterized in that: In step S1, the expression of the scheduling target F1 with the maximum power generation is: Where: t is the time period number used in the medium- and long-term optimization scheduling model of the integrated water, wind, solar and storage cascade in the basin; Δt t is the length of time period t; T is the number of time periods t included in the scheduling period; N w 、N s and N h They are the number of wind power stations, photovoltaic power stations and hydropower stations participating in the dispatching and operation of the cascade water-wind-solar-storage integrated multi-energy complementary base in the basin; and are the average outputs of wind power station j, photovoltaic power station k and hydropower station l in time period t; j = 1, 2, ..., N w ; k = 1, 2, ..., N s ; l=1,2,...,N h ; The expression of the dispatching target F2 with the maximum power generation benefit is: in: and are the power generation benefits of wind power station j, photovoltaic power station k and hydropower station l in time period t respectively; and are the on-grid electricity prices of wind power station j, photovoltaic power station k and hydropower station l in time period t.

4. A basin cascade water, wind, solar and storage integrated scheduling and operation simulation method considering long-term and short-term nested correction according to claim 3, characterized in that: Step S2 is specifically as follows: solving the medium- and long-term optimization scheduling model of the integrated water, wind, solar and storage cascade in the basin, and obtaining the optimal medium- and long-term operation mode of the power source that meets the scheduling objectives and constraints, including: the average output of each hydropower station, wind power station and photovoltaic power station in each time period t during the scheduling period, and the water level of each hydropower station in each time period t; wherein, for hydropower station l, its average output in time period t is expressed as The water level at the end of time period t is expressed as 5. A basin cascade water, wind, solar and storage integrated scheduling and operation simulation method considering long-term and short-term nested correction according to claim 4, characterized in that: Step S3 is as follows: the maximum absorption rate of new energy or the best matching of source and network of the integrated multi-energy complementary base of cascade water, wind, light and storage in the basin is taken as the dispatching target, and the average output of hydropower station l in time period t is obtained based on the medium- and long-term optimal dispatching model of cascade water, wind, light and storage in the basin And the predicted output of wind power station j in each time period t' during the dispatch period And the output of photovoltaic power station k in each time period t' during the dispatch period Taking into account the TTC restrictions of transmission lines or grid requirements, the characteristics of hydropower stations and pumped storage power stations, a long-short-term nested correction model is constructed; where t' is the time period number used in the long-short-term nested correction model.

6. A basin cascade water, wind, solar and storage integrated scheduling and operation simulation method considering long-term and short-term nested correction according to claim 5, characterized in that: The expression of the dispatching target F3 with the maximum new energy absorption rate of the integrated multi-energy complementary base of water, wind, light and storage in the basin is: Where: Δt' t is the length of time period t', Δt' t Less than Δt t ; T' is the number of time periods t' included in the scheduling period; N st The number of all pumped-storage power stations participating in the dispatching and operation of the cascade water, wind, solar and storage integrated multi-energy complementary base in the basin; and are the average outputs of wind power station j, photovoltaic power station k, hydropower station l and pumped storage power station m in time period t'; Pd st The power generation corresponding to the difference in storage capacity between the beginning and the end of the dispatch period of the pumped storage power station; The expression of the dispatching target F4 with the best source-grid matching of the integrated multi-energy complementary base of water, wind, solar and storage in the basin is: Among them: PR t' is the residual load of the power grid in time period t', that is, the output N of the power transmission line required by the power grid in time period t' load,t' The actual output P of the transmission line in time period t' t' The difference, PR t' =N load,t' -P t' ; is the average grid residual load during the dispatch period, that is, 7. The method for simulating the operation of integrated scheduling of cascade water, wind, solar and storage in a watershed considering long-term and short-term nested correction according to claim 1 is characterized in that: Step S4.1 specifically includes: Step S4.1.1: The time length of the period t used in the medium- and long-term optimization scheduling model of the integrated water, wind, solar and storage cascade in the basin is Δt. t , time length Δt t One or more days; each day of period t is used as a small correction cycle, and each day has multiple periods t'; Step S4.1.2, for each day of time period t, determine the adjustable output of hydropower station l for each time period t' within the day Specifically, the average output of hydropower station l in time period t obtained by the medium- and long-term complementary scheduling scheme of water, wind and solar power is As the average output of hydropower station l in each period t' of each day in period t, the average output of each period t' is deducted from the minimum technical output of the corresponding hydropower station in period t' to obtain the adjustable output of hydropower station l in each period t' within the day The formula is: in: is the minimum technical output of hydropower station l in time period t'; Step S4.1.3, for each day in time period t, determine the remaining transmission capacity of the transmission line in each time period t' The maximum transmission capacity N of the transmission line in time period t' t' Or the output N of the transmission line required by the power grid in time period t' load,t' Based on the above, the short-term predicted output of wind and photovoltaic power stations in time period t' and the minimum technical output of hydropower stations in time period t' are deducted to obtain the remaining power transmission capacity of the power transmission line in each time period t' within the day. The formula is: or in: If the dispatch target of the long-term and short-term nested correction model is to maximize the absorption rate of new energy, then select formula (6); if the dispatch target of the long-term and short-term nested correction model is to achieve the best matching between the source and the grid, then select formula (7); Step S4.1.4, based on the power balance, the output of the hydropower station l in each period t' is corrected to obtain the output of the hydropower station l in the period t' after the correction based on the power balance. Based on the adjustable output of the hydropower station at each time period t' within l day obtained in step S4.1.2 and the remaining transmission capacity of the transmission line in each time period t' obtained in step S4.1.3 The adjustable output within the day is reduced by using the method of load shedding The sum is redistributed to each period t' within the day, and the output of hydropower station l in period t' after correction based on power balance is obtained. The formula is: And satisfy in: is the adjustable output of hydropower station l in the daily period t'; a is the number of periods t' included in a day, that is, a=24 / Δt' t ; b is the number of days in the current period t'; Step S4.1.5: for each day of period t, repeat steps S4.1.2-S4.1.4 to obtain the output of each day of period t' after the power balance correction. That is, the output of hydropower station l in each time period t' within time period t Step S4.1.6: Based on the water balance, the output of hydropower station l in each time period t' within time period t Further correction is made to obtain the output of hydropower station l in each time period t' within time period t after correction based on water balance, which is Specifically, the hydropower output constraint repair strategy based on the final water level is adopted to correct the output of the hydropower station, including: (1) Based on the output of hydropower station l at each time period t' in time period t obtained in step S4.1.5 The method of determining water level by electricity is used to calculate backwards for each period t' to obtain the final water level of the hydropower station l in period t (2) Comparison of water levels and water level like ε is the maximum allowable deviation of the water level, and the following method is used to correct the output of the hydropower station: if Then reduce the output of hydropower station l in each period t' within period t Right now in, is the output correction of the hydropower station, obtained by trial calculation; based on the output of the hydropower station l in each time period t' within the time period t after correction The final water level of the hydropower station l in time period t is obtained by using the method of determining water level by electricity satisfy if Then increase the output of hydropower station l in each period t' within period t Right now in, is the maximum allowable output of hydropower station l in time period t'; based on the corrected output of hydropower station l in time period t' The final water level of the hydropower station l in time period t is obtained by using the method of determining water level by electricity satisfy if The output of the hydropower station is not corrected, and the output of the hydropower station l in each period t' within the period t is That is 8. The method for simulating the operation of integrated scheduling of cascade water, wind, solar and storage in a watershed considering long-term and short-term nested correction according to claim 1 is characterized in that: Step S4.3 is specifically as follows: like It is determined that the pumped storage power station is in the pumped storage state; if If the transmission line has a surplus transmission capacity, the pumped storage power station is determined to be in a power generation state; the pumped storage power station determines its average output in time period t' according to certain operating principles and the generation strategy of the boundary of the pumped storage power station output feasible region The operating characteristics of pumped storage power stations include: The operating characteristics of pumped storage power plants need to consider the order of commissioning, operating principles and unit types of pumped storage power plants; The order of operation is that the pumped-storage power station with the highest pumping and generating cycle efficiency is put into operation first, that is, pumping and storing water and power generation are given priority; if the pumping and generating cycle efficiencies of multiple pumped-storage power stations are the same, the pumped-storage power station with a larger maximum storage capacity is put into operation first; at the same time, the order in which the pumped-storage power stations are put into operation also needs to take into account the unit factors, especially for fixed-speed units; There are two operating principles for pumped storage power stations: one is the principle of "pumping as much as possible" + "generating as much as possible", and the other is the principle of "pumping as much as possible" + "multi-day joint optimization of power generation"; The unit types include two types: one is a variable speed unit, which does not consider the full pumping requirement of a single unit of a pumped storage power station; the other is a fixed speed unit, which considers the full pumping requirement of a single unit of a pumped storage power station; the pumping power of the pumped storage power station unit does not consider the continuous value within a certain range when the single unit is fully pumped, which is any value that satisfies the maximum and minimum pumping power constraints of the pumped storage power station unit; the pumping power of the pumped storage power station unit can only take the maximum pumping power of the unit when the single unit is fully pumped; the output of the pumped storage power station is determined according to different combinations of the output conditions of each unit; The output of a pumped-storage power station should consider the constraints of the installed capacity of the pumped-storage power station and the maintenance arrangement of the units, as well as the storage capacity constraints of the pumped-storage power station during the period and the storage capacity constraints at the beginning and end of the period. The strategy for generating the boundary of the feasible region of the output of the pumped-storage power station is used to determine the feasible range of the output of the pumped-storage power station, which specifically includes: Step S4.3.1, the output process of the pumped storage power station and the energy storage process of the pumped storage power station satisfy the energy storage balance constraint equation of the pumped storage power station: in: E m,t' is the storage capacity of the pumped storage power station m at the beginning of time period t'; and are the pumping power and generating power of the pumped storage power station m in time period t' respectively; and At least one of them has a value of 0 and specifies and are the pumping efficiency and power generation efficiency of the pumped storage power station m, respectively; E m,t'+1 is the storage capacity of the pumped storage power station m at the end of time period t'+1; Step S4.3.2: If the basin cascade water-wind-solar-storage integrated multi-energy complementary base contains multiple pumped storage power stations, then execute steps S4.3.3-S4.3.7 for each pumped storage power station in sequence: Step S4.3.3, determine the working status of the pumped storage power station m in time period t': Specifically, according to the latest Determine whether the pumped storage power station m is in a pumped storage state or a power generation state; Step S4.3.4, preliminarily generate the output feasible region boundary of pumped storage power station m in time period t' in, and They are the upper and lower limits of the output feasible region boundary of the pumped storage power station m in time period t': If the pumped storage power station m is in the pumped storage state at time period t', the upper and lower limits of its output feasible region boundary at time period t' are determined according to formula (13): If pumped storage power station m If the system is in the power generation state during the period t', the upper and lower limits of the output feasible region boundary during the period t' are determined according to formula (14): in: and They are the maximum pumping power and maximum generating power of pumped-storage power station m in period t' after considering the installed capacity of the pumped-storage power station and the maintenance arrangement of the units; It is the remaining transmission capacity of the transmission line of the cascade hydro-wind-solar-storage integrated multi-energy complementary base in the basin at time period t', or the gap between the actual output of the transmission line and the transmission output required by the power grid; Step S4.3.5, generate the storage capacity constraint boundary of pumped storage power station m in time period t' in, and are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m in time period t' respectively; (1) For a pumped storage power station m, the initial storage capacity of the dispatch period is Based on the forward sequence calculation method, the energy storage constraint boundary in time period t' is generated using formula (15): For a pumped storage power station m, the storage capacity at the end of the dispatch period is Based on the reverse calculation method, formula (16) is used to generate the energy storage constraint boundary in time period t': in: and They are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m at the end of period t'=0, i.e., the beginning of period t'=1, obtained by the forward sequence calculation method; and are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m at the end of the time period t'=T' obtained by the reverse calculation method; and are the storage capacity of pumped storage power station m at the beginning and end of the dispatch period respectively; and are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m at the end of time period t' obtained by the forward sequence calculation method; and are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m at the end of time period t' obtained by the reverse calculation method; and are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m at the end of time period t'-1 obtained by the forward sequence calculation method; and are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m at the end of time period t'+1 obtained by the reverse calculation method; and E m are the maximum and minimum storage capacities of the pumped storage power station m, respectively; (2) Using formula (17) to obtain the envelope, generate the storage capacity constraint boundary of the pumped storage power station m in time period t': in: and are the upper and lower limits of the storage capacity constraint boundary of the pumped storage power station m in time period t' respectively; Step S4.3.6, based on the storage capacity constraint boundary of the pumped storage power station m in time period t' obtained in step S4.3.5 As well as the energy balance constraint equation of the pumped storage power station in step S4.3.1, the output feasible region boundary of the pumped storage power station m in time period t' obtained in step S4.3.4 After correction, the output feasible region boundary of the pumped storage power station m in time period t' is obtained. in, and are the upper and lower limits of the output feasible region boundary of the modified pumped storage power station m in time period t'; Step S4.3.7, determine the actual output of the pumped-storage power station m in time period t' according to the upper and lower limits of the output feasible region boundary of the pumped-storage power station m in time period t' after correction According to the actual output of the pumped storage power station m in time period t' renew Then continue to determine the actual output of the next pumped storage power station in time period t'.

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