Coordinated operation optimization method and system for multiple types of pumped storage units

Abstract

The invention belongs to the technical field of pumped storage unit operation optimization, and discloses a coordinated operation optimization method and system for multiple types of pumped storage units. The method comprises the following steps: establishing a reservoir capacity change constraint that a constant-speed pumping and storage unit, a variable-speed pumping and storage unit and a hydroelectric generating unit share the same reservoir; establishing power balance constraints between the constant-speed pumped storage unit, the variable-speed pumped storage unit, the hydroelectric generating unit, the thermal power generating unit, the wind power output and the photovoltaic output and the local load; establishing a multi-objective optimization function for cooperative operation of multiple types of units, wherein the multi-objective optimization function comprises minimum operation cost of all types of units and minimum average moment of residual load of a power grid; and under operation constraints including the reservoir capacity change constraint and the power balance constraint, solving the multi-objective optimization function to obtain startup and shutdown states of each type of unit and output of each type of unit in the new energy scene s, and realizing coordinated operation of the multiple types of pumping and storage units. According to the invention, coordinated operation optimization of different types of pumped storage units can be realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of pumped storage unit operation optimization, and more specifically, relates to a method and system for optimizing the coordinated operation of multiple types of pumped storage units. Background Art

[0002] In recent years, with the large-scale access of renewable energy (wind power and photovoltaic) to the power system, the operation of the power grid has faced increasing challenges. These new energy sources have obvious volatility and uncertainty, making the balance of power supply and demand more complicated. In this context, pumped storage power stations, as an important peak-shaving means in the power system, have more flexible operating modes and adjustment capabilities. They can start and stop quickly, and flexibly switch working conditions, and play the role of grid-connected power generation, frequency and phase modulation, peak shaving and valley filling, energy storage and accident standby. This plays a vital role in improving the power grid's ability to absorb intermittent energy and ensuring the safety of the power grid.

[0003] Traditional pumped storage power station optimization dispatching models are mainly aimed at fixed-speed pumped storage units, and relatively less attention is paid to variable-speed pumped storage units. Since different types of pumped storage units have different operating characteristics and efficiency curves, their operating performance under different working conditions varies significantly. How to effectively coordinate these pumped storage units has become a difficult problem in power dispatching.

[0004] In addition, in order to simplify the model, pumped storage power stations usually use a single objective function. However, in the actual operation of pumped storage units, it is often necessary to meet the optimization requirements of multiple objectives at the same time, both to minimize the cost in terms of economy and to ensure peak load demand. However, the traditional model fails to fully consider the problems of multi-objective optimization and coordinated operation of multiple types of units, resulting in the pumped storage power station being unable to ensure the coordinated operation between units when dealing with the uncertainty of new energy access and complex scheduling tasks. Summary of the invention

[0005] In view of the above defects or improvement needs of the prior art, the present invention provides a method and system for optimizing the coordinated operation of multiple types of pumped-storage units, which aims to achieve coordinated operation optimization of different types of pumped-storage units.

[0006] To achieve the above object, the present invention provides a method for optimizing coordinated operation of multiple types of pumped storage units, comprising:

[0007] Establish the reservoir capacity change constraints for fixed-speed pumped storage units, variable-speed pumped storage units and hydropower units sharing the same reservoir: in, They represent the water storage capacity of the upper reservoir and the lower reservoir at time t under the new energy scenario s, It represents the power generation of fixed-speed pumped storage units, variable-speed pumped storage units and hydropower units in the period of Δt, It represents the pumping volume of the fixed-speed pumped storage unit and the variable-speed pumped storage unit in the period of Δt, where Δt is the interval between two adjacent moments;

[0008] Establish power balance constraints between fixed-speed pumped storage units, variable-speed pumped storage units, hydropower units, thermal power units, wind power output, photovoltaic output and local loads;

[0009] Establish a multi-objective optimization function for the coordinated operation of multiple types of units, including minimizing the operating cost of each type of unit and minimizing the average moment of the residual load of the power grid;

[0010] Under the operating constraints including the reservoir capacity change constraint and the power balance constraint, the multi-objective optimization function is solved to obtain the start and shutdown status of each type of unit and the output of each type of unit under the new energy scenario s, so as to achieve coordinated operation optimization of multiple types of pumped storage units.

[0011] Furthermore, the power generation of the fixed-speed pumped storage unit, variable-speed pumped storage unit and hydropower unit in the Δt period is The calculation method is: Among them, c g Indicates the conversion factor of fixed-speed and variable-speed pumped storage units; They represent the power generation of fixed-speed pumped storage units, variable-speed pumped storage units and hydropower units at time t under the new energy scenario s respectively;

[0012] The pumping volume of the fixed speed pumped storage unit and the variable speed pumped storage unit in the period of Δt The calculation method is: Among them, c p Indicates the pumping coefficient of fixed-speed and variable-speed pumped-storage units.

[0013] Furthermore, the operation constraints also include:

[0014] The start and stop constraints of the fixed-speed pumped storage units under power generation conditions, the minimum start and stop time constraints, the upper and lower limits of power generation constraints, the vibration zone constraints, the power generation and flow conversion relationship constraints, the fixed power pumping constraints under pumping conditions, and the mutual exclusion constraints between power generation conditions and pumping conditions;

[0015] The start and stop constraints of variable-speed pumped storage units under power generation conditions, the minimum start and stop time constraints, the upper and lower limits of power generation, the vibration zone constraints, the power generation and flow conversion relationship constraints, the variable power pumping constraints under pumping conditions, and the mutual exclusion constraints between power generation conditions and pumping conditions;

[0016] The upper and lower limits of the power generation of the hydropower unit, the start and stop constraints of the unit, the minimum start and stop time constraints, the vibration zone constraints, and the power generation and flow conversion relationship constraints;

[0017] The start and stop constraints of thermal power units, the minimum start and stop time constraints, the upper and lower limits of power generation constraints, and the climbing constraints;

[0018] As well as the output range constraints of wind power and photovoltaic power.

[0019] Furthermore, the operating costs of all types of units include the start-up and shutdown costs and expected power generation costs of each type of unit;

[0020] Solving the multi-objective optimization function includes:

[0021] The solution process is divided into the day-ahead phase and the real-time phase;

[0022] In the day-ahead stage, under the start-stop constraints and minimum start-stop time constraints corresponding to each type of unit, the start-stop state of each type of unit is obtained with the minimum start-stop cost as the optimization goal; wherein each type of unit includes a fixed-speed pumped storage unit, a variable-speed pumped storage unit, a hydropower unit and a thermal power unit;

[0023] In the real-time stage, under the upper and lower limit constraints on power generation corresponding to each type of unit, the vibration zone constraints, the power generation and flow conversion relationship constraints, the fixed power pumping constraints under pumping conditions, the variable power pumping constraints under pumping conditions, the mutual exclusion constraints and climbing constraints between power generation conditions and pumping conditions, as well as the reservoir capacity change constraints and the power balance constraints, the weighted sum of the expected power generation cost and the average moment of the grid residual load is minimized as the optimization goal, and the output of each type of unit under the new energy scenario s is obtained.

[0024] Furthermore, the power balance constraint is calculated as follows:

[0025]

[0026] Among them, P load,t represents the local load at time t, P W,t,s , P V,t,s They represent the power dispatch values ​​of wind power and photovoltaic power at time t under the new energy scenario s respectively; Jsp , Jvp , J hp , J Th Respectively represent the total number of fixed-speed pumped storage units, variable-speed pumped storage units, hydropower units, and thermal power units; They represent the power generation of fixed-speed pumped storage unit i, variable-speed pumped storage unit i, hydropower unit i, and thermal power unit i at time t under the new energy scenario s respectively; It represents the pumping power of fixed-speed pumped-storage unit j and variable-speed pumped-storage unit j at time t under the new energy scenario s.

[0027] Furthermore, the calculation method for minimizing the start-stop cost is:

[0028] f 1st =(C su n su +C sd n sd )+(C vu n vu +C vd n vd )+(C hu n hu +C hd n hd )+(C thu n thu +C thd n thd )

[0029] In the formula, F 1st represents the start-up and shutdown costs of each type of unit; C su , C vu , C hu , C thu are the startup costs of a single fixed-speed pumped storage unit, a variable-speed pumped storage unit, a hydropower unit, and a thermal power unit, respectively. su 、n vu 、n hu 、n thu are the total number of starts corresponding to the scheduling period T; C sd , C vd , C hd , C thd are the downtime costs of a single fixed-speed pumped storage unit, a variable-speed pumped storage unit, a hydropower unit, and a thermal power unit, respectively. sd 、n vd 、n hd 、n thd are the total number of shutdowns corresponding to the scheduling period T respectively.

[0030] Furthermore, the weighted sum of the expected power generation cost and the average moment of the grid residual load is minimized by:

[0031]

[0032] In the formula, F 2nd represents the weighted sum of the expected power generation cost of each type of unit and the average moment of the residual load of the power grid; C spg , C vpg , C hpg , C thg is the power generation cost of fixed-speed pumped storage units, variable-speed pumped storage units, hydropower units and thermal power units; C W , CPV is the cost of wind power and photovoltaic power generation; ρ s is the probability of each new energy scenario appearing; P W,max,t,s , P V,max,t,s They represent the predicted power generation values ​​of wind power and photovoltaic power at time t under the new energy scenario s; C t,s is the residual load of the power grid; 1 and ω 2 Represents the weight coefficient.

[0033] The present invention also provides a coordinated operation optimization system for multiple types of pumped storage units, comprising a computer-readable storage medium and a processor;

[0034] The computer-readable storage medium is used to store executable instructions;

[0035] The processor is used to read the executable instructions stored in the computer-readable storage medium to execute any one of the above-mentioned methods for optimizing the coordinated operation of multiple types of pumped storage units.

[0036] The present invention also provides a computer-readable storage medium having a computer program stored thereon, and when the program is executed by a processor, the method for optimizing the coordinated operation of multiple types of pumped storage units as described in any one of the above items is implemented.

[0037] The present invention also provides a computer program product, comprising a computer program, which, when executed on a computer, enables the computer to execute any one of the above-mentioned methods for optimizing coordinated operation of multiple types of pumped storage units.

[0038] In general, the above technical solutions conceived by the present invention can achieve the following beneficial effects:

[0039] (1) The method for optimizing coordinated operation of multiple types of pumped storage units of the present invention realizes the synergy constraints of various types of units by establishing the reservoir capacity change constraints of the constant-speed pumped storage units, variable-speed pumped storage units and hydropower units sharing the same reservoir, as well as the power balance constraints between the constant-speed pumped storage units, variable-speed pumped storage units, hydropower units, thermal power units, wind power output and photovoltaic output and local load. Under the operation constraints including the synergy constraints, the multi-objective optimization function for the coordinated operation of multiple types of units is solved, including the minimum operation cost of all types of units and the minimum average moment of the residual load of the power grid. The multi-objective optimization function can not only minimize the cost in terms of economy, but also ensure the peak load demand. In this way, the start-up and shutdown states of various types of units and the output of various types of units under the new energy scenario s can realize the coordinated operation of different types of pumped storage units.

[0040] (2) Furthermore, considering that traditional methods usually assume that new energy scenarios are deterministic when solving the problem of coordinated operation of pumped-storage power stations, the uncertainty of new energy sources such as wind power and photovoltaics is rarely taken into account. To this end, the present invention adopts a two-stage stochastic optimization model that considers wind power uncertainty to deal with the problem of new energy uncertainty. Specifically, based on the multi-objective stochastic optimization model of the present invention, the solution process is divided into two stages. In the day-ahead stage, the optimization goal is to minimize the start-up and shutdown costs of each type of unit, and determine the variables that are unrelated to the new energy scenario, that is, the start-up and shutdown status of each type of unit; in the real-time stage, under the operating constraints of each type of unit in each new energy scenario, the optimization goal is to minimize the weighted sum of the expected power generation cost of each type of unit and the average moment of the residual load of the power grid, and the unit output in each wind power and photovoltaic scenario is used as the decision variable to ensure the coordinated operation of the pumped-storage unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a flow chart of the method for optimizing the coordinated operation of multiple types of pumped storage units in an embodiment of the present invention. DETAILED DESCRIPTION

[0042] 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 intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0043] Example 1

[0044] like Figure 1 As shown, an embodiment of the present invention provides a method for optimizing coordinated operation of multiple types of pumped storage units, which mainly includes:

[0045] Establish a reservoir capacity change constraint for fixed-speed pumped storage units, variable-speed pumped storage units and hydropower units sharing the same reservoir; the reservoir capacity change constraint is used to characterize the water storage capacity of the upper reservoir at time t+1 under new energy scenarios such as wind power and photovoltaic power. satisfy: The water storage capacity of the lower reservoir at time t+1 satisfy: in, They represent the water storage capacity of the upper reservoir and the lower reservoir at time t under the new energy scenario s, It represents the power generation of fixed-speed pumped storage units, variable-speed pumped storage units and hydropower units in the period of Δt, It represents the pumping volume of the fixed-speed pumped storage unit and the variable-speed pumped storage unit in the period of Δt, where Δt is the interval between two adjacent moments in the unit dispatch cycle T;

[0046] Establish power balance constraints between fixed-speed pumped storage units, variable-speed pumped storage units, hydropower units, thermal power units, wind power output, photovoltaic output and local loads;

[0047] Establish a multi-objective optimization function for the coordinated operation of multiple types of units, including minimizing the operating cost of all types of units and minimizing the average moment of the residual load of the power grid;

[0048] Under the operating constraints including the above-mentioned reservoir capacity change constraint and power balance constraint, the above-mentioned multi-objective optimization function is solved to obtain the start and shutdown status of each type of unit and the output of each type of unit under the new energy scenario s.

[0049] In the embodiment of the present invention, the power generation of the fixed speed pumped storage unit, the variable speed pumped storage unit and the hydropower unit in the Δt period is for: Among them, c g Indicates the conversion factor of fixed-speed and variable-speed pumped storage units; They respectively represent the power generation capacity of the fixed-speed pumped-storage unit, variable-speed pumped-storage unit and hydropower unit at time t under the new energy scenario s.

[0050] Pumping volume of fixed-speed pumped storage units and variable-speed pumped storage units in the period Δt for: Among them, c p Indicates the pumping coefficient of fixed-speed and variable-speed pumped-storage units.

[0051] As a preferred implementation method, the operating constraints in the embodiment of the present invention also include: constraints related to fixed-speed pumped-storage units, constraints related to variable-speed pumped-storage units, constraints related to hydropower units, constraints related to thermal power units, wind power units, and output range constraints of photovoltaic modules.

[0052] In an embodiment of the present invention, the constraints related to the constant-speed pumped-storage unit include unit start and stop constraints under power generation conditions, minimum start and stop time constraints, upper and lower limit constraints on power generation, vibration zone constraints, and power generation and flow conversion relationship constraints; constant power pumping constraints under pumping conditions; and mutually exclusive constraints between power generation conditions and pumping conditions.

[0053] In power generation condition:

[0054]

[0055] In pumping conditions:

[0056]

[0057] Extraction of mutually exclusive constraints:

[0058] Among them, formula (1) represents the start-stop state association constraint of the fixed-speed pumped storage unit, formula (2) represents the start-stop mutually exclusive constraint of the fixed-speed pumped storage unit, and formula (1)-formula (2) represent the start-stop constraint of the unit under the power generation condition; formula (3) represents the minimum continuous start-stop time constraint of the fixed-speed pumped storage unit, formula (4) represents the power generation constraint of the fixed-speed pumped storage unit, formula (5) represents the vibration zone constraint of the fixed-speed pumped storage unit, formula (6) represents the power generation and flow conversion relationship constraint of the fixed-speed pumped storage unit, formula (7) represents the power generation conversion coefficient of the pumped storage unit, and formula (8) represents the constant power pumping constraint of the fixed-speed pumped storage unit. Formula (9) represents the pumped power generation mutually exclusive constraint of the fixed-speed pumped storage unit.

[0059] In the above formulas, Indicates whether the fixed-speed pumped storage unit i is in the pumping and power generation condition at time t. If the unit is in pumping condition, on the contrary If the unit is in power generation condition, on the contrary represents the startup and shutdown variables of the fixed-speed pumped storage unit i at time t. Indicates that the unit is started, otherwise it is equal to 0. Similarly, Indicates that the unit is shut down, otherwise it is equal to 0; They represent the minimum start-up time and minimum shutdown time of fixed-speed pumped storage unit i respectively; represents the rated pumping power of fixed-speed pumped-storage unit i under new energy scenario s; Indicates the minimum and maximum power generation of fixed-speed pumped storage unit i; represents the power generation of fixed-speed pumped storage unit i at time t under the new energy scenario s; They represent the minimum and maximum power generation of the fixed-speed pumped storage unit i respectively; represents the minimum and maximum power generation of fixed-speed pumped storage unit i in the mth feasible interval; represents the power generation of fixed-speed pumped storage unit i at time t in the mth feasible interval under the new energy scenario s; Q sp,t,s represents the pumping flow of all fixed-speed pumped storage units at time t under the new energy scenario s; represents the power generation of all fixed-speed pumped storage units at time t under the new energy scenario s; Δt represents the interval between two adjacent moments in the unit scheduling cycle; c g Indicates fixed speed and variable speed

[0060] Conversion coefficient of pumped storage unit power generation; η g is the conversion efficiency coefficient of power generation and flow, ρ 0 is the density of water, g is the acceleration of gravity, and h is the average head difference between the upper and lower reservoirs; It represents the pumping power of the fixed-speed pumped storage unit i at time t under the new energy scenario s.

[0061] In an embodiment of the present invention, the constraints related to the variable-speed pumped-storage unit include: unit start and stop constraints under power generation conditions, minimum start and stop time constraints, upper and lower limit constraints on power generation, vibration zone constraints, power generation and flow conversion relationship constraints; variable power pumping constraints under pumping conditions; and mutually exclusive constraints between power generation conditions and pumping conditions.

[0062] In power generation condition:

[0063]

[0064]

[0065] In pumping conditions:

[0066]

[0067] Extraction of mutually exclusive constraints:

[0068] Among them, formula (10) represents the associated constraint of the start-stop state of the variable speed pumped storage unit, formula (11) represents the start-stop mutually exclusive constraint of the variable speed pumped storage unit, formula (12) represents the minimum continuous start-stop time constraint of the variable speed pumped storage unit, formula (13) represents the power generation constraint of the variable speed pumped storage unit, formula (14) represents the vibration zone constraint of the variable speed pumped storage unit, formula (15) represents the power generation and flow conversion relationship constraint of the variable speed pumped storage unit, formula (16) represents the pumping constraint of the variable speed pumped storage unit, and formula (17) represents the pumping power generation mutually exclusive constraint of the variable speed pumped storage unit.

[0069] In the above formulas, Indicates whether the variable speed pumped storage unit i is in the pumping and power generation condition at time t. If the unit is in pumping condition, on the contrary If the unit is in power generation condition, on the contrary represents the start and stop variables of variable speed pumped storage unit i at time t. Indicates that the unit is started, otherwise it is equal to 0. Similarly; They represent the minimum start-up time and minimum shutdown time of variable speed pumped storage unit i respectively; represents the power generation of variable speed pumped storage unit i at time t under the new energy scenario s; Indicates the minimum and maximum power generation of variable speed pumped storage unit i; represents the pumping power of variable-speed pumped storage unit i at time t under the new energy scenario s; represents the minimum and maximum power generation of variable speed pumped storage unit i in the mth feasible interval; Q vp,t,s It represents the pumping volume of the variable speed unit at time t under the new energy scenario s; represents the power generation power of variable speed pumped storage unit i at the mth feasible interval at time t under the new energy scenario s; It represents the power generation capacity of all variable-speed pumped storage units at time t under the new energy scenario s.

[0070] In the embodiment of the present invention, the constraints related to the hydropower unit include upper and lower limit constraints on power generation, unit start and stop constraints, minimum start and stop time constraints, vibration zone constraints, and power generation and flow conversion relationship constraints.

[0071]

[0072] Among them, formula (18) represents the upper and lower limit constraints of the power generation of the hydropower unit, formula (19) represents the associated constraints of the start and stop states of the hydropower unit, formula (20) represents the mutually exclusive constraints of the start and stop of the hydropower unit, formula (21) represents the maximum start-up times constraint of each hydropower unit, formula (22) represents the minimum start and stop time constraint of the hydropower unit, formula (23) represents the maximum operating time constraint of the hydropower unit, formula (24) represents the vibration zone constraint of the hydropower unit, and formula (25) represents the power generation and flow conversion relationship constraint of the hydropower unit.

[0073] In the above formulas, represents the power generation of hydropower unit i at time t under the new energy scenario s; Indicates whether the hydropower unit i is in the power generation condition at time t, If the hydropower unit is in power generation condition, on the contrary Indicates the minimum and maximum power generation of hydropower unit i; Represents the startup and shutdown variables of hydropower unit i at time t, which are 0 and 1 variables. Indicates that the unit is started, otherwise it is equal to 0. Similarly; T represents the scheduling period, Indicates the maximum number of startup times; Indicates the minimum start-up time and minimum shutdown time of hydropower unit i; MAX time Indicates the maximum operating time of the hydropower unit; represents the minimum and maximum power generation of hydropower unit i in the mth feasible interval; represents the power generation of hydropower unit i at time t in the mth feasible interval under the new energy scenario s; Q hp,t,s represents the pumping flow of the hydropower unit at time t under the new energy scenario s; It represents the power generation of all hydropower units at time t under the new energy scenario s.

[0074] In the embodiment of the present invention, the constraints related to the thermal power unit include unit start and stop constraints, minimum start and stop time constraints, upper and lower limit constraints on power generation, and climbing constraints.

[0075]

[0076] Among them, formula (26) represents the upper and lower limit constraints of the thermal power unit output, formulas (27) and (28) represent the upper and lower limit constraints of the thermal power unit ramp rate, formula (29) represents the minimum start-up time constraint of the thermal power unit, and formula (30) represents the minimum shutdown time constraint of the thermal power unit.

[0077] In the above formulas, u i,t represents the start / stop status of thermal power unit i at time t, u i,t =0 means the unit is stopped, u i,t =1 means the unit is started; represents the output of thermal power unit i at time t under the new energy scenario s, Respectively represent the maximum and minimum output of thermal power unit i; Respectively represent the up and down climbing rates of thermal power unit i; They represent the maximum startup rate and the maximum shutdown rate of thermal power unit i respectively; T S 、T 0 They respectively represent the minimum shutdown and startup time of thermal power units.

[0078] In the embodiment of the present invention, the output range constraints of wind turbines and photovoltaic modules are as follows:

[0079]

[0080] Formula (31) is the wind power and photovoltaic power constraints, P W,t,s , P V,t,s They represent the dispatching values ​​of wind power and photovoltaic power generation at time t under the new energy scenario s; P W,max,t,s , P V,max,t,s They respectively represent the predicted power generation values ​​of wind power and photovoltaic power at time t under the new energy scenario s.

[0081] In the embodiment of the present invention, the synergy constraints of the constant-speed pumped-storage units, the variable-speed pumped-storage units and the hydropower units specifically include the reservoir capacity change constraints of the constant-speed pumped-storage units, the variable-speed pumped-storage units and the hydropower units sharing the same reservoir and the power balance constraints between the constant-speed pumped-storage units, the variable-speed pumped-storage units, the hydropower units, the thermal power units, the wind power output and the photovoltaic output and the local load.

[0082] As a preferred implementation, the reservoir capacity change constraint for the fixed-speed pumped storage unit, the variable-speed pumped storage unit and the hydropower unit sharing the same reservoir is:

[0083]

[0084] Among them, formula (32) is the water storage constraint of the upper reservoir, formula (33) is the water storage constraint of the lower reservoir, formula (34) is the water storage change constraint of the upper reservoir, formula (35) is the water storage change constraint of the lower reservoir, and formula (36) represents the pumping conversion coefficient of the pumped storage unit.

[0085] In the above formulas, They represent the lower and upper limits of the water storage capacity of the upper reservoir respectively; They represent the lower and upper limits of the water storage capacity of the lower reservoir respectively; They represent the upper reservoir and the lower reservoir in the new energy scenario s. t The water storage capacity at the time; c p Indicates the pumping coefficient of fixed-speed and variable-speed pumped storage units; η p is the conversion efficiency coefficient of pumping power and flow rate.

[0086] Power balance constraints between fixed-speed pumped storage units, variable-speed pumped storage units, hydropower units, thermal power units, wind power output, photovoltaic output and local loads:

[0087]

[0088] Formula (37) is the power balance constraint, P load,t represents the local load at time t, P W,t,s , P V,t,s They represent the power dispatch values ​​of wind power and photovoltaic power at time t under the new energy scenario s respectively; Jsp , Jvp , J hp , J Th Respectively represent the total number of fixed-speed pumped storage units, variable-speed pumped storage units, hydropower units, and thermal power units; They represent the power generation of fixed-speed pumped storage unit i, variable-speed pumped storage unit i, hydropower unit i, and thermal power unit i at time t under the new energy scenario s respectively; It represents the pumping power of fixed-speed pumped-storage unit j and variable-speed pumped-storage unit j at time t under the new energy scenario s.

[0089] As a preferred implementation method, a multi-objective optimization function for the coordinated operation of multiple types of units is established, specifically including:

[0090] Establish objective function 1, which is the minimum operating cost of all types of units, including the sum of the start-up and shutdown costs of each type of unit and the expected power generation cost:

[0091]

[0092] In the formula, C su , C sd , C vu , C vd , C hu , C hd , C thu , C thd They are the startup and shutdown costs of a single fixed-speed pumped storage unit, a variable-speed pumped storage unit, a hydropower unit, and a thermal power unit; n su 、n sd 、n vu 、n vd 、n hu 、n hd 、n thu 、n thd are the total number of starts and stops of a single fixed-speed pumped storage unit, variable-speed pumped storage unit, hydropower unit and thermal power unit within the dispatch period T; C spg , C vpg , C hpg , C thg is the power generation cost of fixed-speed pumped storage units, variable-speed pumped storage units, hydropower units and thermal power units; C W , C PV is the cost of wind power and photovoltaic power generation; ρ s is the probability of occurrence of each new energy scenario; S is the total number of new energy scenarios.

[0093] Establish objective function 2, that is, the minimum average moment of the residual load of the power grid.

[0094]

[0095] Among them, C t,s is the remaining load of the power grid; T is the dispatching period.

[0096] As a preferred implementation method, a multi-objective weighted method is used to convert the multi-objective function into a single-objective function, and then an optimization method is used to solve it to obtain the start and shutdown status of each type of unit and the output of each type of unit under the new energy scenario s.

[0097] As a further design of the present invention, in order to effectively deal with the uncertainty of new energy and further ensure the coordinated operation of pumped storage units, under the above operation constraints, when solving the above multi-objective optimization function, a two-stage stochastic programming model considering the uncertainty of wind power is used for help, specifically including:

[0098] The solution process is divided into the day-ahead phase and the real-time phase;

[0099] In the day-ahead stage, under the constraints of the start-stop state and the minimum start-stop time of hydropower units, thermal power units, fixed-speed pumped storage units and variable-speed pumped storage units, the objective function is to minimize the start-stop cost of each type of unit, and an optimization algorithm is used to solve the objective function to obtain the start-stop state of each type of unit. In the embodiment of the present invention, the corresponding model is as follows:

[0100] f 1st =(C su n su +C sd n sd )+(C vu n vu +C vd n vd )+(C hu n hu +C hd n hd )+(C thu n thu +C thd n thd ) (40)

[0101] st.(1)-(4),(9)-(12),(17),(19)-(23),(29)-(30)(41)

[0102] Among them, F 1st Represents the start-up and shutdown costs of each type of unit.

[0103] In the real-time stage, based on the start-up and shutdown status of each type of unit obtained by solving the day-ahead stage, under the operating constraints of each type of unit in each new energy scenario (including the upper and lower limits of power generation of each type of unit, vibration zone constraints, power generation and flow conversion relationship constraints, pumping power constraints, climbing constraints, etc., as well as reservoir capacity change constraints and power balance constraints), the objective function is the minimum weighted sum of the expected power generation cost of each type of unit and the average moment of the remaining load of the power grid, and the optimization algorithm is used to solve the objective function to obtain the output of each type of unit in the new energy scenario s. In the embodiment of the present invention, the corresponding model is as follows:

[0104]

[0105] st.(5)-(8),(13)-(16),(24)-(28),(31)-(37)(43)

[0106] Among them, F 2nd Represents the weighted sum of the expected power generation cost of each type of unit and the average moment of the residual load of the power grid; ω 1 and ω 2 Represents the weight coefficient, which can be determined based on experience.

[0107] This paper proposes a multi-objective stochastic optimization model for the coordinated operation optimization problem of fixed-speed pumped storage units, variable-speed pumped storage units and hydropower units, taking into account the two objectives of minimizing the operating cost of pumped storage power stations and optimizing the peak-shaving performance, and adopts a two-stage stochastic programming model to deal with the uncertainty of new energy. The model consists of two stages, namely the day-ahead stage and the real-time stage. The decision variables in the day-ahead stage include the start and stop status of each type of unit, and the decision variables in the real-time stage are the unit outputs in each wind power and photovoltaic scenario, ensuring the coordinated operation of pumped storage units.

[0108] Example 2

[0109] An embodiment of the present invention provides a coordinated operation optimization system for multiple types of pumped storage units, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of the coordinated operation optimization method for multiple types of pumped storage units in the above-mentioned embodiment 1 are implemented.

[0110] The relevant technical solutions are the same as above and will not be described in detail here.

[0111] Example 3

[0112] An embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the steps of the method for optimizing coordinated operation of multiple types of pumped storage units in the above-mentioned embodiment 1 are implemented.

[0113] Specifically, the memory may include a high-speed random access memory, and may also include a non-volatile memory, such as a hard disk, an internal memory, a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card (Flash Card), at least one disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0114] The relevant technical solutions are the same as above and will not be described in detail here.

[0115] Example 4

[0116] An embodiment of the present application provides a computer program product, including a computer program. When the computer program is executed on a computer, the computer executes the steps of the method for optimizing coordinated operation of multiple types of pumped storage units in the above-mentioned embodiment 1.

[0117] The relevant technical solutions are the same as above and will not be described in detail here.

[0118] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for optimizing the coordinated operation of multiple types of pumped storage units, characterized in that: include: Establish the reservoir capacity change constraints for fixed-speed pumped storage units, variable-speed pumped storage units and hydropower units sharing the same reservoir: in, They represent the water storage capacity of the upper reservoir and the lower reservoir at time t under the new energy scenario s, It represents the power generation of fixed-speed pumped storage units, variable-speed pumped storage units and hydropower units in the period of Δt, It represents the pumping volume of the fixed-speed pumped storage unit and the variable-speed pumped storage unit in the period of Δt, where Δt is the interval between two adjacent moments; Establish power balance constraints between fixed-speed pumped storage units, variable-speed pumped storage units, hydropower units, thermal power units, wind power output, photovoltaic output and local loads; Establish a multi-objective optimization function for the coordinated operation of multiple types of units, including minimizing the operating cost of each type of unit and minimizing the average moment of the residual load of the power grid; Under the operating constraints including the reservoir capacity change constraint and the power balance constraint, the multi-objective optimization function is solved to obtain the start and shutdown status of each type of unit and the output of each type of unit under the new energy scenario s, so as to achieve coordinated operation optimization of multiple types of pumped storage units.

2. The method for optimizing coordinated operation of multiple types of pumped storage units according to claim 1 is characterized in that: The power generation of the fixed-speed pumped storage unit, variable-speed pumped storage unit and hydropower unit in the Δt period The calculation method is: Among them, c g Indicates the conversion factor of fixed-speed and variable-speed pumped storage units; They represent the power generation of fixed-speed pumped storage units, variable-speed pumped storage units and hydropower units at time t under the new energy scenario s respectively; The pumping volume of the fixed speed pumped storage unit and the variable speed pumped storage unit in the period of Δt The calculation method is: Among them, c p Indicates the pumping coefficient of fixed-speed and variable-speed pumped-storage units.

3. The method for optimizing coordinated operation of multiple types of pumped storage units according to claim 1 or 2, characterized in that: The operating constraints also include: The start and stop constraints of the fixed-speed pumped storage units under power generation conditions, the minimum start and stop time constraints, the upper and lower limits of power generation constraints, the vibration zone constraints, the power generation and flow conversion relationship constraints, the fixed power pumping constraints under pumping conditions, and the mutual exclusion constraints between power generation conditions and pumping conditions; The start and stop constraints of variable-speed pumped storage units under power generation conditions, the minimum start and stop time constraints, the upper and lower limits of power generation, the vibration zone constraints, the power generation and flow conversion relationship constraints, the variable power pumping constraints under pumping conditions, and the mutual exclusion constraints between power generation conditions and pumping conditions; The upper and lower limits of the power generation of the hydropower unit, the start and stop constraints of the unit, the minimum start and stop time constraints, the vibration zone constraints, and the power generation and flow conversion relationship constraints; The start and stop constraints of thermal power units, the minimum start and stop time constraints, the upper and lower limits of power generation constraints, and the climbing constraints; As well as the output range constraints of wind power and photovoltaic power.

4. The method for optimizing coordinated operation of multiple types of pumped storage units according to claim 3 is characterized in that: The operating costs of all types of units include the start-up and shutdown costs and expected power generation costs of each type of unit; Solving the multi-objective optimization function includes: The solution process is divided into the day-ahead phase and the real-time phase; In the day-ahead stage, under the start-stop constraints and minimum start-stop time constraints corresponding to each type of unit, the start-stop state of each type of unit is obtained with the minimum start-stop cost as the optimization goal; wherein each type of unit includes a fixed-speed pumped storage unit, a variable-speed pumped storage unit, a hydropower unit and a thermal power unit; In the real-time stage, under the upper and lower limit constraints on power generation corresponding to each type of unit, the vibration zone constraints, the power generation and flow conversion relationship constraints, the fixed power pumping constraints under pumping conditions, the variable power pumping constraints under pumping conditions, the mutual exclusion constraints and climbing constraints between power generation conditions and pumping conditions, the output range constraints of wind power and photovoltaic power, as well as the reservoir capacity change constraints and the power balance constraints, the weighted sum of the expected power generation cost and the average moment of the grid residual load is minimized as the optimization goal, and the output of each type of unit under the new energy scenario s is obtained.

5. The method for optimizing coordinated operation of multiple types of pumped storage units according to claim 4 is characterized in that: The power balance constraint is calculated as follows: Among them, P load,t represents the local load at time t, P W,t,s , P V,t,s They represent the power dispatch values ​​of wind power and photovoltaic power at time t under the new energy scenario s respectively; Jsp , Jvp , J hp , J Th Respectively represent the total number of fixed-speed pumped storage units, variable-speed pumped storage units, hydropower units, and thermal power units; They represent the power generation of fixed-speed pumped storage unit i, variable-speed pumped storage unit i, hydropower unit i, and thermal power unit i at time t under the new energy scenario s respectively; It represents the pumping power of fixed-speed pumped-storage unit j and variable-speed pumped-storage unit j at time t under the new energy scenario s.

6. The method for optimizing coordinated operation of multiple types of pumped storage units according to claim 5 is characterized in that: The calculation method for minimizing the start-stop cost is: minF 1st =(C su n su +C sd n sd )+(C vu n vu +C vd n vd )+(C hu n hu +C hd n hd )+(C thu n thu +C thd n thd ) In the formula, F 1st represents the start-up and shutdown costs of each type of unit; C su , C vu , C hu , C thu are the startup costs of a single fixed-speed pumped storage unit, a variable-speed pumped storage unit, a hydropower unit, and a thermal power unit, respectively. su 、n vu 、n hu 、n thu are the total number of starts corresponding to the scheduling period T; C sd , C vd , C hd , C thd are the downtime costs of a single fixed-speed pumped storage unit, a variable-speed pumped storage unit, a hydropower unit, and a thermal power unit, respectively. sd 、n vd 、n hd 、n thd are the total number of shutdowns corresponding to the scheduling period T respectively.

7. The method for optimizing coordinated operation of multiple types of pumped storage units according to claim 5, characterized in that: The calculation method for minimizing the weighted sum of the expected power generation cost and the average moment of the grid residual load is: In the formula, F 2nd represents the weighted sum of the expected power generation cost of each type of unit and the average moment of the residual load of the power grid; C spg , C vpg , C hpg , C thg is the power generation cost of fixed-speed pumped storage units, variable-speed pumped storage units, hydropower units and thermal power units; C W , C PV is the cost of wind power and photovoltaic power generation; ρ s is the probability of each new energy scenario appearing; P W,max,t,s , P V,max,t,s They represent the predicted power generation values ​​of wind power and photovoltaic power at time t under the new energy scenario s; C t,s is the residual load of the power grid; ω1 and ω2 represent weight coefficients.

8. A coordinated operation optimization system for multiple types of pumped storage units, characterized in that: comprising a computer readable storage medium and a processor; The computer-readable storage medium is used to store executable instructions; The processor is used to read the executable instructions stored in the computer-readable storage medium to execute the coordinated operation optimization method of multiple types of pumped storage units as described in any one of claims 1-7.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by the processor, the method for optimizing the coordinated operation of multiple types of pumped storage units as described in any one of claims 1 to 7 is implemented.

10. A computer program product, characterized in that It includes a computer program, which, when executed on a computer, enables the computer to execute the method for optimizing the coordinated operation of multiple types of pumped storage units as described in any one of claims 1 to 7.

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