Short-term optimization operation method for water-wind-light-storage multi-energy complementary system

Abstract

The invention relates to the technical field of power systems, and particularly discloses a short-term optimization operation method for a water-wind-light-storage multi-energy complementary system. The method comprises the following steps: S1, constructing a water-wind-light-storage multi-energy complementary short-term optimization operation model by taking maximization of the load tracking degree of the water-wind-light-storage multi-energy complementary system, minimization of the intraday output fluctuation of a downstream daily regulation hydropower station and maximization of the daily total power generation amount of clean energy as targets; s2, constructing constraint conditions of a water-wind-light-storage multi-energy complementary short-term optimization operation model; and S3, solving and calculating the water-wind-light-storage multi-energy complementary short-term optimization operation model by adopting a two-stage calculation dimensionality reduction decoupling method to realize short-term optimization operation of the water-wind-light-storage multi-energy complementary system. The method has the advantages that a multi-target scheduling model for water, wind, light and storage multi-energy complementary short-term optimization operation is established, a two-stage calculation model efficient dimension reduction decoupling solving method is provided, and optimization operation decision of the water, wind, light and storage multi-energy complementary system is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of electric power systems, and in particular to a short-term optimization operation method for a hydro-wind-solar-storage multi-energy complementary system. Background Art

[0002] In recent years, my country's clean renewable energy such as wind power and photovoltaics has developed rapidly. However, due to meteorological factors, its power output has obvious randomness, volatility and intermittency, which restricts the large-scale grid-connected operation of wind and solar resources. Taking advantage of the rapid and flexible adjustment of the power output of hydropower stations and pumped storage power stations, the dispatching and operation of water, wind, solar and storage multi-energy complementation has become one of the important ways to develop and utilize wind and solar resources. However, the short-term optimal operation decision of the water, wind, solar and storage multi-energy complementation system is affected by multiple constraints, and the calculation process is very difficult to solve. Therefore, it is urgent to study a short-term optimal operation method for the water, wind, solar and storage multi-energy complementation system to achieve accurate and efficient decision-making in the short-term dispatching and operation of the water, wind, solar and storage multi-energy complementation system, and provide important technical support for the large-scale utilization of water, wind, solar and storage multi-energy complementation and clean renewable energy. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a short-term optimized operation method for a water-wind-solar-storage multi-energy complementary system.

[0004] The purpose of the present invention is achieved by the following technical solution: a short-term optimization operation method of a water-wind-solar-storage multi-energy complementary system, the method comprising the following steps:

[0005] Step S1, constructing a short-term optimization operation model of water-wind-solar-storage multi-energy complementary system with the goals of maximizing the load tracking degree of the water-wind-solar-storage multi-energy complementary system, minimizing the intraday output fluctuation of the downstream daily regulation hydropower station, and maximizing the total daily power generation of clean energy;

[0006] Step S2, constructing the constraint conditions of the short-term optimization operation model of water, wind, solar and storage multi-energy complementarity;

[0007] Step S3, adopting a two-stage calculation dimensionality reduction decoupling method to solve and calculate the short-term optimal operation model of the water-wind-solar-storage multi-energy complementary system, so as to realize the short-term optimal operation of the water-wind-solar-storage multi-energy complementary system.

[0008] Specifically, the objective function for maximizing the load tracking degree of the water-wind-solar-storage multi-energy complementary system is as follows:

[0009]

[0010] Where ρ is the load tracking degree; t is the time period variable, T is the total number of time periods (T = 24); N t r is the total power generation output of the system in period t; P t is the power load of the power grid in the tth period; is the average load level of the power grid; pv, w, h, ps are the numbers of solar, wind, hydropower stations and pumped storage units respectively; PV, W, H, PS are the total number of solar, wind, hydropower stations and pumped storage units respectively; is the photovoltaic output in the tth period; is the wind power output in period t; k is the charge / discharge output of the pumped storage unit in the tth period. When the value is positive, it means that the pumped storage power station is discharging electricity in the tth period. When the value is negative, it means that the pumped storage power station is pumping electricity in the tth period. h is the output coefficient of the hth hydropower station; Q t h is the power generation flow of the h-th hydropower station in the t-th period; is the output head of the h-th hydropower station in the t-th period.

[0011] Specifically, the objective function for minimizing the intra-day output fluctuation of the downstream daily regulating hydropower station is as follows:

[0012]

[0013] Where, F is the output fluctuation index of the downstream power station; is the average value of the transmitted power; t is the time period variable, T is the total number of time periods (T = 24); H is the total number of hydropower station units; h is the unit number of the hydropower station; k h is the output coefficient of the hth hydropower station; Q t h is the power generation flow of the h-th hydropower station in the t-th period; is the output head of the h-th hydropower station in the t-th period.

[0014] Specifically, the objective function for maximizing the total daily power generation of clean energy is:

[0015]

[0016] Where, E is the total power generation of cascade hydropower, wind power and solar power storage in a day; m t is the number of hours in the tth period; t is the period variable, T is the total number of periods (T = 24); pv, w, h, ps are the numbers of solar, wind, hydropower stations and pumped storage units respectively; PV, W, H, PS are the total number of solar, wind, hydropower stations and pumped storage units respectively; is the photovoltaic output in the tth period; is the wind power output in period t; k is the charge / discharge output of the pumped storage unit in the tth period. When the value is positive, it means that the pumped storage power station is discharging electricity in the tth period. When the value is negative, it means that the pumped storage power station is pumping electricity in the tth period. his the output coefficient of the hth hydropower station; Q t h is the power generation flow of the h-th hydropower station in the t-th period; is the output head of the h-th hydropower station in the t-th period.

[0017] Specifically, the constraints of the short-term optimization operation model of water, wind, solar and storage multi-energy complementarity include grid-side constraints, power station output constraints, hydropower station hydraulic constraints and pumped storage power station hydraulic constraints;

[0018] The grid-side constraints include transmission channel constraints and power abandonment rate constraints, as shown in the following formula:

[0019]

[0020] Where N d is the transmission capacity of the dth transmission section; E is the total amount of abandoned electricity during the cascade hydropower, wind and solar power periods; is the output that cannot be absorbed by the pv-th photovoltaic power station in the t period; is the output that cannot be absorbed by the w-th wind power station in the t-th period; is the water discharge of the h-th hydropower station in the t-th period, k h is the output coefficient of the hth hydropower station; Q t h is the power generation flow of the h-th hydropower station in the t-th period; is the output water head of the h-th hydropower station in the t-th period, is the charge / discharge output of the pumped storage unit in the t period; pv, w, h, ps are the numbers of the solar, wind, hydropower stations and pumped storage units respectively; PV, W, H, PS are the total number of solar, wind, hydropower stations and pumped storage units respectively; t is the period variable, T is the total number of periods (T = 24); E is the total power generation of the cascade hydro-wind-solar storage unit in a day; m t is the number of hours in the tth period.

[0021] Specifically, the power station output constraints include wind power output constraints, photovoltaic output constraints, hydropower output constraints, and pumped storage power station output constraints, as shown in the following formula:

[0022]

[0023]

[0024] In the formula, is the wind power output in period t; is the installed capacity of the w-th wind power station; is the output coefficient of the w-th wind power station in the t-th period; Divided into the minimum and maximum output of the w-th wind power station in the t-th period; is the photovoltaic output in the tth period; is the installed capacity of the pvth photovoltaic power station; f t pv is the output coefficient of the pv-th photovoltaic power station in the t-th period; is the minimum and maximum output of the pvth photovoltaic power station in the tth period; are the minimum and maximum outputs allowed for the hth power station in the tth period; k h is the output coefficient of the hth hydropower station; Q t h is the power generation flow of the h-th hydropower station in the t-th period; is the output water head of the h-th hydropower station in the t-th period; is the charge / discharge output of the pumped storage unit in period t; g is the acceleration of gravity; η T is the power generation efficiency of the pumped storage unit under power generation conditions; is the power generation flow of the pumped storage unit in the t period under power generation conditions; is the average generating head of the pumped storage unit in the tth period under power generation conditions; is the pumping flow of the pumped storage unit in the tth period under the pumping condition; is the average pumping head of the pumped storage unit in the tth period under pumping conditions; η P is the pump efficiency of the pumped storage unit under pumping conditions; It is the minimum allowable output of the pumped storage unit under pumping conditions; It is the maximum allowable output of the pumped storage unit under power generation conditions.

[0025] Specifically, the hydraulic constraints of the hydropower station include water balance constraints in the time dimension, water balance constraints in the space dimension, reservoir water level constraints, reservoir water level daily fluctuation constraints, power generation flow constraints, and discharge flow constraints, as shown in the following formula:

[0026]

[0027] In the formula, is the final storage capacity of the h-th hydropower station in the t-th period; is the initial storage capacity of the h-th hydropower station in the t-th period; is the inflow of the h-th hydropower station in the t-th period; Q t h is the power generation flow of the h-th hydropower station in the t-th period; is the water discharge of the h-th hydropower station in the t-th period; △t is the number of seconds in the t-th period; is the interval flow of the h-th hydropower station in the t-th period; is the water level of the hth hydropower station at the tth period; are the upper and lower limits of the water level of the h-th hydropower station in the t-th period; |Z h,t+1 -Z h,t | is the absolute value of the difference in water levels at adjacent times of the h-th hydropower station; Z h,allow is the daily water level variation allowed for the hth reservoir; are the maximum and minimum power generation flows of the h-th hydropower station in the t-th period, respectively; are the maximum and minimum discharge flows of the h-th hydropower station in the t-th period, respectively; f v,z () is the relationship expression between reservoir water level and storage capacity; is the downstream water level of the h-th hydropower station at the t-th period; It is the expression of the relationship between the tailwater level and the discharge flow of the reservoir.

[0028] Specifically, the hydraulic constraints of the pumped storage power station include reference flow constraints and discharge flow constraints, as shown in the following formula:

[0029]

[0030] In the formula, is the final storage capacity of the upper and lower reservoirs of the pumped storage unit at the tth period; is the initial storage capacity of the upper and lower reservoirs of the pumped storage unit at the tth period; is the inflow flow of the upper and lower reservoirs of the pumped storage unit in the tth period; is the power generation flow of the upper and lower reservoirs of the pumped storage unit in the tth period; is the water discharge flow of the upper and lower reservoirs of the pumped storage unit at the tth period; It is the maximum value of the discharge flow of the pumped storage unit when discharging water for power generation; It is the maximum value of the flow rate used by the pumped storage unit for pumped storage; is the charge / discharge output of the pumped storage unit in the tth period; △t is the number of seconds in the tth period.

[0031] Specifically, step S3 uses a two-stage calculation dimensionality reduction decoupling method to solve and calculate the short-term optimization operation model of water, wind, solar and storage multi-energy complementarity, and the specific steps include:

[0032] Step S31, first read the water, wind, solar and storage calculation parameters, and then initialize the parameters and population;

[0033] Step S32, determining the first stage fitness function;

[0034] Step S33, initializing the number of calculations and setting the number of cycles, then calculating the initial fitness, and obtaining the initial external file according to the non-dominated sorting;

[0035] Step S34, determine whether the number of calculations is less than the number of cycles. If so, update the particle speed and position to determine whether the constraint conditions are met; if not, update the particle speed and position again until the constraint conditions are met, then calculate the current fitness, update the individual extreme value and the global extreme value, and update the external archive;

[0036] Step S35, determine whether the updated external file is smaller than the external file memory, if so, update the calculation times, and increase the calculation times by 1; if not, sort and eliminate the individuals at the end of the file according to the congestion degree, and then update the calculation times, and increase the calculation times by 1; then jump to step S34 until the calculation times are greater than the loop times;

[0037] Step S36, then output the Pareto optimal solution set, and use the fuzzy optimization method to determine the optimal solution; calculate the target relative superiority matrix of each solution; calculate the comprehensive relative superiority of the decision set, and take the solution with the maximum comprehensive relative superiority as the optimal solution;

[0038] Step S37, initializing the operating state of the pumped storage unit according to the initialization parameters and the population, calculating the remaining load based on the optimal solution in step S36, and then determining the operating condition of the pumped storage power station;

[0039] Step S38, determining the operating status of the pumped storage power station unit, and then back-calculating the pumping\power generation flow;

[0040] Step S39, determine whether the constraint conditions are met, if not, return to step S38; if yes, back-calculate the final storage capacity of the upper and lower reservoirs, and then update the upper and lower reservoir water level process;

[0041] Step S310, determine whether the upper and lower reservoir water level process meets the accuracy, if not, return to step S32; if yes, take the upper and lower reservoir water level process as the initial operation trajectory, and read the water, wind and light related parameters;

[0042] Step S311, perform POA optimization calculation to determine whether the constraints are met. If so, save the optimal water level state of the objective function for this period; if not, update and adjust according to the boundary value of the constraint condition, and recalculate the objective function and its water level state for this period;

[0043] Step S312, determine whether all power stations are traversed, if not, return to step S311; if yes, determine whether all time periods are traversed, if not, return to step S311, if yes, determine whether the accuracy is met, if not, adjust the water level process of the upstream reservoir, and then return to step S33; if yes, the calculation ends.

[0044] The present invention has the following advantages:

[0045] In order to solve the production decision-making problem of short-term optimal scheduling of water-wind-solar-storage multi-energy complementary system, a multi-objective scheduling model for short-term optimal operation of water-wind-solar-storage multi-energy complementary system is established, and an efficient dimensionality reduction and decoupling solution method of the two-stage calculation model is proposed to realize the optimal operation decision of the water-wind-solar-storage multi-energy complementary system, providing important technical support for water-wind-solar-storage multi-energy complementary system and large-scale utilization of clean renewable energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 It is a schematic flow chart of the optimization operation method of the present invention;

[0047] Figure 2 It is a schematic diagram of the flow chart of the dimensionality reduction and decoupling solution method of the present invention. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention 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 invention and are not used to limit the present invention, that is, the embodiments described are only part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0049] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention.

[0050] It should be noted that relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "including a..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0051] The present invention is further described below in conjunction with the accompanying drawings, but the protection scope of the present invention is not limited to the following description. Figure 1 to Figure 2As shown, a short-term optimization operation method for a water-wind-solar-storage multi-energy complementary system is provided, the method comprising the following steps: Step S1, constructing a short-term optimization operation model for a water-wind-solar-storage multi-energy complementary system with the goals of maximizing the load tracking degree of the water-wind-solar-storage multi-energy complementary system, minimizing the intraday output fluctuation of the downstream daily regulating hydropower station, and maximizing the total daily power generation of clean energy;

[0052] Step S2, constructing the constraint conditions of the short-term optimization operation model of water, wind, solar and storage multi-energy complementarity;

[0053] Step S3, aiming at the problem that it is difficult to directly solve the non-inferior solution set of the three objective functions of the short-term optimal operation model of the water-wind-solar-storage multi-energy complementarity, a two-stage calculation dimensionality reduction decoupling method is used to solve and calculate the short-term optimal operation model of the water-wind-solar-storage multi-energy complementarity, so as to realize the short-term optimal operation of the water-wind-solar-storage multi-energy complementarity system.

[0054] Furthermore, the objective function for maximizing the load tracking degree of the water-wind-solar-storage multi-energy complementary system is as follows:

[0055]

[0056] In the formula, ρ is the load tracking degree. The closer its value is to 1, the better the tracking performance of the hydropower, wind, solar and storage power generation output is, the more consistent it is with the changing characteristics of the load demand, and the more conducive it is to the safe and stable operation of the power system; t is the time period variable, and T is the total number of time periods (T = 24); is the total power generation output of the system in period t; P t is the power load of the power grid in the tth period; is the average load level of the power grid; pv, w, h, ps are the numbers of solar, wind, hydropower stations and pumped storage units respectively; PV, W, H, PS are the total number of solar, wind, hydropower stations and pumped storage units respectively; is the photovoltaic output in the tth period; is the wind power output in period t; k is the charge / discharge output of the pumped storage unit in the tth period. When the value is positive, it means that the pumped storage power station is discharging electricity in the tth period. When the value is negative, it means that the pumped storage power station is pumping electricity in the tth period. h is the output coefficient of the hth hydropower station; Q t h is the power generation flow of the h-th hydropower station in the t-th period; is the output head of the h-th hydropower station in the t-th period.

[0057] Furthermore, the objective function for minimizing the intra-day output fluctuation of the downstream daily regulating hydropower station is as follows:

[0058]

[0059] Where, F is the output fluctuation index of the downstream power station; is the average value of the transmitted power; t is the time period variable, T is the total number of time periods (T = 24); H is the total number of hydropower station units; h is the unit number of the hydropower station; k h is the output coefficient of the hth hydropower station; Q t h is the power generation flow of the h-th hydropower station in the t-th period; is the output head of the h-th hydropower station in the t-th period.

[0060] Furthermore, the objective function for maximizing the total daily power generation of clean energy is:

[0061]

[0062] Where, E is the total power generation of cascade hydropower, wind power and solar power storage in a day; m t is the number of hours in the tth period; t is the period variable, T is the total number of periods (T = 24); pv, w, h, ps are the numbers of solar, wind, hydropower stations and pumped storage units respectively; PV, W, H, PS are the total number of solar, wind, hydropower stations and pumped storage units respectively; is the photovoltaic output in the tth period; is the wind power output in period t; k is the charge / discharge output of the pumped storage unit in the tth period. When the value is positive, it means that the pumped storage power station is discharging electricity in the tth period. When the value is negative, it means that the pumped storage power station is pumping electricity in the tth period. h is the output coefficient of the hth hydropower station; Q t h is the power generation flow of the h-th hydropower station in the t-th period; is the output head of the h-th hydropower station in the t-th period.

[0063] Furthermore, the constraints of the short-term optimization operation model of the water, wind, solar and storage multi-energy complementarity include grid-side constraints, power station output constraints, hydropower station hydraulic constraints and pumped storage power station hydraulic constraints;

[0064] The grid-side constraints include transmission channel constraints and power abandonment rate constraints, as shown in the following formula:

[0065]

[0066] Where N d is the transmission capacity of the dth transmission section; E is the total amount of abandoned electricity during the cascade hydropower, wind and solar power periods; is the output that cannot be absorbed by the pv-th photovoltaic power station in the t period; is the output that cannot be absorbed by the w-th wind power station in the t-th period; is the water discharge of the h-th hydropower station in the t-th period, k h is the output coefficient of the hth hydropower station; Q t h is the power generation flow of the h-th hydropower station in the t-th period; is the output water head of the h-th hydropower station in the t-th period, is the charge / discharge output of the pumped storage unit in the t period; pv, w, h, ps are the numbers of the solar, wind, hydropower stations and pumped storage units respectively; PV, W, H, PS are the total number of solar, wind, hydropower stations and pumped storage units respectively; t is the period variable, T is the total number of periods (T = 24); E is the total power generation of the cascade hydro-wind-solar storage unit in a day; m t is the number of hours in the tth period.

[0067] Furthermore, the power station output constraints include wind power output constraints, photovoltaic output constraints, hydropower output constraints, and pumped storage power station output constraints, as shown in the following formula:

[0068]

[0069]

[0070]

[0071] In the formula, is the wind power output in period t; is the installed capacity of the w-th wind power station; is the output coefficient of the w-th wind power station in the t-th period; Divided into the minimum and maximum output of the w-th wind power station in the t-th period; is the photovoltaic output in the tth period; is the installed capacity of the pvth photovoltaic power station; f t pv is the output coefficient of the pv-th photovoltaic power station in the t-th period; is the minimum and maximum output of the pvth photovoltaic power station in the tth period; are the minimum and maximum outputs allowed for the hth power station in the tth period; k h is the output coefficient of the hth hydropower station; Q t h is the power generation flow of the h-th hydropower station in the t-th period; is the output water head of the h-th hydropower station in the t-th period; is the charge / discharge output of the pumped storage unit in period t; g is the acceleration of gravity; η T is the power generation efficiency of the pumped storage unit under power generation conditions; is the power generation flow of the pumped storage unit in the t period under power generation conditions; is the average generating head of the pumped storage unit in the tth period under power generation conditions; is the pumping flow of the pumped storage unit in the tth period under the pumping condition; is the average pumping head of the pumped storage unit in the tth period under pumping conditions; η P is the pump efficiency of the pumped storage unit under pumping conditions; It is the minimum allowable output of the pumped storage unit under pumping conditions; It is the maximum allowable output of the pumped storage unit under power generation conditions.

[0072] Furthermore, the hydraulic constraints of the hydropower station include water balance constraints in the time dimension, water balance constraints in the space dimension, reservoir water level constraints, reservoir water level daily fluctuation constraints, power generation flow constraints, and discharge flow constraints, as shown in the following formula:

[0073]

[0074]

[0075] In the formula, V is the final storage capacity of the h-th hydropower station in the t-th period; t h is the initial storage capacity of the h-th hydropower station in the t-th period; is the inflow of the h-th hydropower station in the t-th period; Q t h is the power generation flow of the h-th hydropower station in the t-th period; is the water discharge of the h-th hydropower station in the t-th period; △t is the number of seconds in the t-th period; is the interval flow of the h-th hydropower station in the t-th period; is the water level of the hth hydropower station at the tth period; are the upper and lower limits of the water level of the h-th hydropower station in the t-th period; |Z h,t+1 -Z h,t | is the absolute value of the difference in water levels at adjacent times of the h-th hydropower station; Z h,allow is the daily water level variation allowed for the hth reservoir; are the maximum and minimum power generation flows of the h-th hydropower station in the t-th period, respectively; are the maximum and minimum discharge flows of the h-th hydropower station in the t-th period, respectively; f v,z () is the relationship expression between reservoir water level and storage capacity; is the downstream water level of the h-th hydropower station at the t-th period; It is the expression of the relationship between the tailwater level and the discharge flow of the reservoir.

[0076] Furthermore, the hydraulic constraints of the pumped storage power station include a reference flow constraint and a discharge flow constraint, as shown in the following formula:

[0077]

[0078] In the formula, V is the final storage capacity of the upper and lower reservoirs of the pumped storage unit at the tth period; t ps,上 、V t ps,下 is the initial storage capacity of the upper and lower reservoirs of the pumped storage unit at the tth period; is the inflow of the upper and lower reservoirs of the pumped storage unit in the tth period; is the power generation flow of the upper and lower reservoirs of the pumped storage unit in the tth period; is the water discharge flow of the upper and lower reservoirs of the pumped storage unit in the tth period; It is the maximum value of the discharge flow of the pumped storage unit when discharging water for power generation; It is the maximum value of the flow rate quoted when the pumped storage unit is pumping water for energy storage; is the charge / discharge output of the pumped storage unit in the tth period; △t is the number of seconds in the tth period.

[0079] Furthermore, the step S3 adopts a two-stage calculation dimensionality reduction decoupling method to solve and calculate the short-term optimization operation model of water, wind, solar and storage multi-energy complementarity, and the specific steps include:

[0080] Step S31, first read the water, wind, solar and storage calculation parameters, and then initialize the parameters and population;

[0081] Step S32, determining the first stage fitness function;

[0082] Step S33, initialize the number of calculations and set the number of cycles, the initial number of calculations is 0, and the number of cycles is set to 1000; then calculate the initial fitness, and obtain the initial external file according to the non-dominated sorting;

[0083] Step S34, determine whether the number of calculations is less than the number of cycles. If so, update the particle speed and position to determine whether the constraint conditions are met; if not, update the particle speed and position again until the constraint conditions are met, then calculate the current fitness, update the individual extreme value and the global extreme value, and update the external archive;

[0084] Step S35, determine whether the updated external file is smaller than the external file memory, if so, update the calculation times, and increase the calculation times by 1; if not, sort and eliminate the individuals at the end of the file according to the congestion degree, and then update the calculation times, and increase the calculation times by 1; then jump to step S34 until the calculation times are greater than the loop times;

[0085] Step S36, then output the Pareto optimal solution set, and use the fuzzy optimization method to determine the optimal solution; calculate the target relative superiority matrix of each solution; calculate the comprehensive relative superiority of the decision set, and take the solution with the maximum comprehensive relative superiority as the optimal solution;

[0086] Step S37, initializing the operating state of the pumped storage unit according to the initialization parameters and the population, calculating the remaining load based on the optimal solution in step S36, and then determining the operating condition of the pumped storage power station;

[0087] Step S38, determining the operating status of the pumped storage power station unit, and then back-calculating the pumping\power generation flow;

[0088] Step S39, determine whether the constraint conditions are met, if not, return to step S38; if yes, back-calculate the final storage capacity of the upper and lower reservoirs, and then update the upper and lower reservoir water level process;

[0089] Step S310, determine whether the upper and lower reservoir water level process meets the accuracy, if not, return to step S32; if yes, take the upper and lower reservoir water level process as the initial operation trajectory, and read the water, wind and light related parameters;

[0090] Step S311, perform POA optimization calculation to determine whether the constraints are met. If so, save the optimal water level state of the objective function for this period; if not, update and adjust according to the boundary value of the constraint condition, and recalculate the objective function and its water level state for this period;

[0091] Step S312, determine whether all power stations are traversed, if not, return to step S311; if yes, determine whether all time periods are traversed, if not, return to step S311; if yes, determine whether the accuracy is met, if not, adjust the water level process of the upstream reservoir, and then return to step S33; if yes, end.

[0092] In step S3, the first stage solves the collaborative optimization problem between the hydropower, wind, solar and storage power generation output and the grid load demand, including the two goals of maximizing the load tracking degree of the multi-energy complementary system and maximizing the total daily power generation of clean energy. The concepts of Pareto and non-dominated sorting are introduced, and a multi-objective particle swarm algorithm is used to solve it; the first stage is decomposed into two layers of calculation, the inner layer optimizes the operation mode of the pumped storage power station unit, and the outer layer optimizes the water level operation mode of the cascade hydropower; since the feasible domain range of the decision variables of the operating state of the pumped storage power station unit is small, the inner layer is solved by a dynamic programming algorithm; in the second stage, based on the calculation results of the first stage, the calculation results of the first stage are used as a step-by-step optimization algorithm ( The initial trajectory of the POA algorithm) is obtained, the relevant variables and parameters are read, and the POA algorithm is used to optimize the water level process of the downstream daily regulating hydropower station. All time periods, all power stations and all constraints are traversed in turn, and the optimization scheme that satisfies the objective function of minimizing the daily output fluctuation of the downstream daily regulating hydropower station is compared and determined; if the accuracy requirement cannot be met, the water level process of the upstream reservoir is updated, and the calculation is restarted in the first stage, making full use of the regulation capacity of the Longtou Reservoir Power Station itself to achieve the goal of minimizing the daily output fluctuation of the downstream daily regulating hydropower station; the optimization calculation of the operation mode of the inner layer pumped-storage power station unit is further refined to solve the problem of coordinated operation of pumped-storage power stations and cascade hydropower. Combined with the operating characteristics of the pumped-storage power station, that is, full-power pumping is usually used in pumping conditions, in order to simplify the difficulty of solving, the full-power discharge power generation operation mode is also adopted in the power generation condition, and the optimization calculation is carried out with each unit of the pumped-storage power station as the dispatching unit; thereby, the decision variables for the optimal operation of the pumped-storage power station can be transformed into solving the operating status of each unit, effectively reducing the scope of solution and the dimension of solution calculation; first, the operating status of the pumped-storage unit is initialized, and the residual load is determined in combination with the outer calculation results, thereby determining the operating conditions of the pumped-storage power station and the operating status of the pumped-storage power station unit, and then back-calculating the pumping or power generation flow, updating the water level process of the upper reservoir and the lower reservoir, and judging whether the accuracy requirements are met. , and finally returns the corresponding calculation result of the fitness function; the outer layer of the cascade hydropower station water level operation mode optimization calculation, the initial population is generated by the multi-objective particle swarm algorithm, and the fitness of the initial population is calculated in combination with the calculation of the inner layer pumped storage power station; then the initial external archive is obtained according to the non-dominated sorting, and the speed and position of the particles are updated according to the optimization mechanism of the external archive, and the current fitness, individual extreme value, global extreme value and external archive are updated accordingly, and the Pareto optimal solution set is output; finally, the fuzzy optimization method is used to determine the optimal solution, and the target relative optimization speed matrix and the comprehensive relative superiority of the decision set of each solution are calculated, and the solution with the largest comprehensive relative optimization speed is selected as the optimal solution.

[0093] The above is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any technician familiar with the art can make many possible changes and modifications to the technical solution of the present invention by using the above-mentioned technical content without departing from the scope of the technical solution of the present invention, or modify it into an equivalent embodiment of equivalent changes. Therefore, any changes, modifications, equivalent changes and modifications made to the above embodiments based on the technology of the present invention without departing from the content of the technical solution of the present invention belong to the protection scope of the present technical solution.

Claims

1. A short-term optimization operation method for a water-wind-solar-storage multi-energy complementary system, characterized in that: The method comprises the following steps: Step S1, constructing a short-term optimization operation model of water-wind-solar-storage multi-energy complementary system with the goals of maximizing the load tracking degree of the water-wind-solar-storage multi-energy complementary system, minimizing the intraday output fluctuation of the downstream daily regulation hydropower station, and maximizing the total daily power generation of clean energy; Step S2, constructing the constraint conditions of the short-term optimization operation model of water, wind, solar and storage multi-energy complementarity; Step S3, adopting a two-stage calculation dimensionality reduction decoupling method to solve and calculate the short-term optimal operation model of the water-wind-solar-storage multi-energy complementary system, so as to realize the short-term optimal operation of the water-wind-solar-storage multi-energy complementary system.

2. The short-term optimization operation method of a water-wind-solar-storage multi-energy complementary system according to claim 1 is characterized by: The objective function for maximizing the load tracking degree of the water-wind-solar-storage multi-energy complementary system is as follows: Where ρ is the load tracking degree; t is the time period variable, and T is the total number of time periods (T = 24); is the total power generation output of the system in period t; P t is the power load of the power grid in the tth period; is the average load level of the power grid; pv, w, h, ps are the numbers of solar, wind, hydropower stations and pumped storage units respectively; PV, W, H, PS are the total number of solar, wind, hydropower stations and pumped storage units respectively; is the photovoltaic output in the tth period; is the wind power output in period t; k is the charge / discharge output of the pumped storage unit in the tth period. When the value is positive, it means that the pumped storage power station is discharging electricity in the tth period. When the value is negative, it means that the pumped storage power station is pumping electricity in the tth period. h is the output coefficient of the hth hydropower station; Q t h is the power generation flow of the h-th hydropower station in the t-th period; is the output head of the h-th hydropower station in the t-th period.

3. The short-term optimization operation method of a water-wind-solar-storage multi-energy complementary system according to claim 1 is characterized by: The objective function for minimizing the intra-day output fluctuation of the downstream daily regulating hydropower station is as follows: Where, F is the output fluctuation index of the downstream power station; is the average value of the transmitted power; t is the time period variable, T is the total number of time periods (T = 24); H is the total number of hydropower station units; h is the unit number of the hydropower station; k h is the output coefficient of the hth hydropower station; Q t h is the power generation flow of the h-th hydropower station in the t-th period; is the output head of the h-th hydropower station in the t-th period.

4. The short-term optimization operation method of a water-wind-solar-storage multi-energy complementary system according to claim 1 is characterized by: The objective function for maximizing the total daily power generation of clean energy is: Where, E is the total power generation of cascade hydropower, wind power and solar power storage in a day; m t is the number of hours in the tth period; t is the period variable, T is the total number of periods (T = 24); pv, w, h, ps are the numbers of solar, wind, hydropower stations and pumped storage units respectively; PV, W, H, PS are the total number of solar, wind, hydropower stations and pumped storage units respectively; is the photovoltaic output in the tth period; is the wind power output in period t; k is the charge / discharge output of the pumped storage unit in the tth period. When the value is positive, it means that the pumped storage power station is discharging electricity in the tth period. When the value is negative, it means that the pumped storage power station is pumping electricity in the tth period. h is the output coefficient of the hth hydropower station; Q t h is the power generation flow of the h-th hydropower station in the t-th period; is the output head of the h-th hydropower station in the t-th period.

5. The short-term optimization operation method of a water-wind-solar-storage multi-energy complementary system according to claim 1 is characterized by: The constraints of the short-term optimization operation model of water, wind, solar and storage multi-energy complementarity include grid-side constraints, power station output constraints, hydropower station hydraulic constraints and pumped storage power station hydraulic constraints; The grid-side constraints include transmission channel constraints and power abandonment rate constraints, as shown in the following formula: Where N d is the transmission capacity of the dth transmission section; E is the total amount of abandoned electricity during the cascade hydropower, wind and solar power periods; is the output that cannot be absorbed by the pv-th photovoltaic power station in the t period; is the output that cannot be absorbed by the w-th wind power station in the t-th period; is the water discharge of the h-th hydropower station in the t-th period, k h is the output coefficient of the hth hydropower station; Q t h is the power generation flow of the h-th hydropower station in the t-th period; is the output water head of the h-th hydropower station in the t-th period, is the charge / discharge output of the pumped storage unit in the t period; pv, w, h, ps are the numbers of the solar, wind, hydropower stations and pumped storage units respectively; PV, W, H, PS are the total number of solar, wind, hydropower stations and pumped storage units respectively; t is the period variable, T is the total number of periods (T = 24); E is the total power generation of the cascade hydro-wind-solar storage unit in a day; m t is the number of hours in the tth period.

6. The short-term optimization operation method of a water-wind-solar-storage multi-energy complementary system according to claim 5 is characterized by: The power station output constraints include wind power output constraints, photovoltaic output constraints, hydropower output constraints, and pumped storage power station output constraints, as shown in the following formula: In the formula, is the wind power output in period t; is the installed capacity of the w-th wind power station; is the output coefficient of the w-th wind power station in the t-th period; Divided into the minimum and maximum output of the w-th wind power station in the t-th period; is the photovoltaic output in period t; is the installed capacity of the pvth photovoltaic power station; f t pv is the output coefficient of the pv-th photovoltaic power station in the t-th period; is the minimum and maximum output of the pvth photovoltaic power station in the tth period; are the minimum and maximum outputs allowed for the hth power station in the tth period; k h is the output coefficient of the hth hydropower station; Q t h is the power generation flow of the h-th hydropower station in the t-th period; is the output water head of the h-th hydropower station in the t-th period; is the charge / discharge output of the pumped storage unit in period t; g is the acceleration of gravity; η T is the power generation efficiency of the pumped storage unit under power generation conditions; is the power generation flow of the pumped storage unit in the t period under power generation conditions; is the average generating head of the pumped storage unit in the tth period under power generation conditions; is the pumping flow of the pumped storage unit in the tth period under the pumping condition; is the average pumping head of the pumped storage unit in the tth period under the pumping condition; η P is the pump efficiency of the pumped storage unit under pumping conditions; It is the minimum allowable output of the pumped storage unit under pumping conditions; It is the maximum allowable output of the pumped storage unit under power generation conditions.

7. The short-term optimization operation method of a water-wind-solar-storage multi-energy complementary system according to claim 5 is characterized by: The hydraulic constraints of the hydropower station include water balance constraints in the time dimension, water balance constraints in the space dimension, reservoir water level constraints, reservoir water level daily fluctuation constraints, power generation flow constraints, and discharge flow constraints, as shown in the following formula: In the formula, V is the final storage capacity of the h-th hydropower station in the t-th period; t h is the initial storage capacity of the h-th hydropower station in the t-th period; is the inflow of the h-th hydropower station in the t-th period; Q t h is the power generation flow of the h-th hydropower station in the t-th period; is the water discharge of the h-th hydropower station in the t-th period; △t is the number of seconds in the t-th period; is the interval flow of the h-th hydropower station in the t-th period; is the water level of the hth hydropower station at the tth period; are the upper and lower limits of the water level of the h-th hydropower station in the t-th period; |Z h,t+1 -Z h,t | is the absolute value of the difference in water levels at adjacent times of the h-th hydropower station; Z h,allow is the daily water level variation allowed for the hth reservoir; are the maximum and minimum power generation flows of the h-th hydropower station in the t-th period, respectively; are the maximum and minimum discharge flows of the h-th hydropower station in the t-th period, respectively; f v,z () is the relationship expression between reservoir water level and storage capacity; is the downstream water level of the h-th hydropower station at the t-th period; It is the expression of the relationship between the tailwater level and the discharge flow of the reservoir.

8. The short-term optimization operation method of a water-wind-solar-storage multi-energy complementary system according to claim 5 is characterized by: The hydraulic constraints of the pumped storage power station include reference flow constraints and discharge flow constraints, as shown in the following formula: In the formula, V is the final storage capacity of the upper and lower reservoirs of the pumped storage unit at the tth period; t ps,上 、V t ps,下 is the initial storage capacity of the upper and lower reservoirs of the pumped storage unit at the tth period; is the inflow flow of the upper and lower reservoirs of the pumped storage unit in the tth period; is the power generation flow of the upper and lower reservoirs of the pumped storage unit in the tth period; is the water discharge flow of the upper and lower reservoirs of the pumped storage unit at the tth period; It is the maximum value of the discharge flow of the pumped storage unit when discharging water for power generation; It is the maximum value of the flow rate used by the pumped storage unit for pumped storage; is the charge / discharge output of the pumped storage unit in the tth period; △t is the number of seconds in the tth period.

9. The short-term optimization operation method of a water-wind-solar-storage multi-energy complementary system according to claim 5 is characterized by: The step S3 adopts a two-stage calculation dimensionality reduction decoupling method to solve and calculate the short-term optimization operation model of water, wind, solar and storage multi-energy complementarity, and the specific steps include: Step S31, first read the water, wind, solar and storage calculation parameters, and then initialize the parameters and population; Step S32, determining the first stage fitness function; Step S33, initializing the number of calculations and setting the number of cycles, then calculating the initial fitness, and obtaining the initial external file according to the non-dominated sorting; Step S34, determine whether the number of calculations is less than the number of cycles. If so, update the particle speed and position to determine whether the constraint conditions are met; if not, update the particle speed and position again until the constraint conditions are met, then calculate the current fitness, update the individual extreme value and the global extreme value, and update the external archive; Step S35, determine whether the updated external file is smaller than the external file memory, if so, update the calculation times, and increase the calculation times by 1; if not, sort and eliminate the individuals at the end of the file according to the congestion degree, and then update the calculation times, and increase the calculation times by 1; then jump to step S34 until the calculation times are greater than the loop times; Step S36, then output the Pareto optimal solution set, and use the fuzzy optimization method to determine the optimal solution; calculate the target relative superiority matrix of each solution; calculate the comprehensive relative superiority of the decision set, and take the solution with the maximum comprehensive relative superiority as the optimal solution; Step S37, initializing the operating state of the pumped storage unit according to the initialization parameters and the population, calculating the remaining load based on the optimal solution in step S36, and then determining the operating condition of the pumped storage power station; Step S38, determining the operating status of the pumped storage power station unit, and then back-calculating the pumping\power generation flow; Step S39, determine whether the constraint conditions are met, if not, return to step S38; if yes, back-calculate the final storage capacity of the upper and lower reservoirs, and then update the upper and lower reservoir water level process; Step S310, determine whether the upper and lower reservoir water level process meets the accuracy, if not, return to step S32; if yes, take the upper and lower reservoir water level process as the initial operation trajectory, and read the water, wind and light related parameters; Step S311, perform POA optimization calculation to determine whether the constraints are met. If so, save the optimal water level state of the objective function for this period; if not, update and adjust according to the boundary value of the constraint condition, and recalculate the objective function and its water level state for this period; Step S312, determine whether all power stations are traversed, if not, return to step S311; if yes, determine whether all time periods are traversed, if not, return to step S311; if yes, determine whether the accuracy is met, if not, adjust the water level process of the upstream reservoir, and then return to step S33; if yes, the calculation ends.

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