Water-wind-light integrated base grid-connected scheduling optimization method, equipment and medium
By building a grid-connected optimization scheduling model of the integrated water, wind and light base, quantifying the relationship between each power supply and evaluating its impact on the system's equivalent inertia, the problems of complex scheduling strategies and poor scheduling capabilities are solved, and efficient scheduling consumption rate is achieved and system frequency stability.
Patent Information
- Application Number
- CN202411608637.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-12
- Publication Date
- 2025-02-11
AI Technical Summary
Under the grid connection conditions of the water, wind and light integrated base, the scheduling strategy is complex, and it is difficult to take into account the complex timing characteristics and extreme scenarios of the wind and light output, resulting in poor scheduling capabilities.
Build a grid-connected optimization scheduling model for integrated water, wind and light bases, quantify the relationship between the hydropower start-up plan and the output of each power supply and DC power transmission demand, and the impact on optimized scheduling through grid-connected method, wind and light ratio, and installed capacity of hydropower , evaluate the impact of the hydropower dispatching plan in different situations on the system's equivalent inertia, and optimize the dispatch based on this.
It improves the scheduling capacity, maximizes the wind and light consumption rate, optimizes the hydropower scheduling plan, and enhances the system's frequency stability and primary frequency regulation capabilities.
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Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of electric power dispatching, and in particular to a method, device and medium for optimizing grid-connected dispatching of a water-wind-solar integrated base. Background Art
[0002] As a clean energy power generation platform, the integrated water, wind and photovoltaic base based on hydropower, wind power and photovoltaic power generation has been widely studied and applied to meet the urgent demand for sustainable energy worldwide. By organically combining hydropower, wind power and photovoltaic power generation units and operating them in coordination through reasonable scheduling strategies, the integrated water, wind and photovoltaic base can smooth out the uncertainty fluctuations in the power generation generated by wind and photovoltaic power generation, thereby improving the stability of the entire power system. And because hydropower generation relies on synchronous generators to connect to the grid, it can not only provide reliable power support for the base, but also effectively improve the system inertia of the entire base and ensure the frequency safety of the power system. When the integrated water, wind and photovoltaic base is connected to the grid, it needs to be coupled with other single energy sources outside the base, such as wind power bases and photovoltaic power bases, to jointly meet the load demand of the power grid. When connected to the grid, the minimum startup plan of hydropower generation in the integrated water, wind and photovoltaic base is the key issue for the optimal scheduling of the base grid connection.
[0003] Domestic and foreign scholars have done a lot of research on the optimization and dispatching of integrated water, wind and solar bases. The prior art studied the dispatching and operation mode of a water, wind and solar integrated multi-energy complementary demonstration base, and proposed a lumped dispatching mode. Through cross-regional power transmission and multi-grid peak regulation, the consumption of new energy has been increased and the problems of power abandonment and power shortage have been solved. Prior art one proposed a method for evaluating the risk of water storage state, and constructed a multi-objective dispatching model to reasonably absorb new energy and reduce the risk of water abandonment and power shortage by adjusting the hydropower operation mode. Prior art two proposed a two-layer optimization modeling and solution method for the joint dispatch of a water, fire, wind and solar multi-energy complementary system, and found that under different scenarios, the multi-energy complementary system can increase thermal power output and reduce overall operating costs. Prior art three studied the flexible regulation role of hydropower in the complementary system, constructed a multi-objective optimization dispatching model considering economic benefits and flexible regulation margin, and proved the supporting role of pumped storage for the flexible operation of the system through examples. Prior art four proposed an optimization model combining a cascade hydropower station with renewable energy generation methods such as wind power and photovoltaics. The example results show that large-scale water-wind-solar hybrid systems have the potential to meet the needs of export power transmission. Prior art five buffers short-term renewable energy uncertainties by supplementing demand, optimizes long-term decisions on hydropower, proposes a two-level multi-objective optimization model that takes both long-term and short-term operations into account, and proposes a power-power coupling method to reduce the computational burden. Prior art six proposes an annual dispatch model for a hydropower-photovoltaic-wind hybrid system that effectively reduces the adverse effects of large-scale renewable energy integration on the power system by maximizing its generation interval and considering stable generation constraints, and uses an interval optimization method to solve the problem that the probability distribution of wind energy, water inflow, and solar radiation is difficult to accurately predict.
[0004] Existing research has mainly focused on the following aspects: dispatching operation mode, water storage status risk assessment, joint dispatching of multi-energy complementary systems, flexible regulation of hydropower, and optimization model of renewable energy generation methods. These research results have achieved certain results in increasing the consumption of renewable energy, solving the problems of power abandonment and power shortage, and reducing operating costs. However, for the grid-connected optimization dispatching of integrated water, wind and solar bases, the existing scenario generation methods have the problem of difficulty in taking into account the complex time series characteristics and correlation of wind and solar output, and it is difficult to consider the problem of extreme scenarios. Summary of the invention
[0005] The technical problem to be solved by the present invention is that the dispatching strategy under grid-connected conditions is complex, it is difficult to take into account the complexity of wind and solar power output, and the dispatching capacity is poor. The purpose is to provide a method, equipment and medium for optimizing the grid-connected dispatching of a water-wind-solar integrated base. With the goal of maximizing the wind-solar power consumption rate, a grid-connected optimization dispatching model for a water-wind-solar integrated base is constructed, and the relationship between the hydropower start-up plan and the output of each power source and the DC power transmission demand is quantified. Through the influence of grid-connected mode, wind-solar ratio, and hydropower installed capacity on the optimized dispatching, the influence of hydropower dispatching plans under different situations on the system equivalent inertia is evaluated, and the grid-connected optimized dispatching can be optimized according to the influence to improve the dispatching capacity.
[0006] The present invention is achieved through the following technical solutions: The first aspect of the present invention provides a method for optimizing grid-connected scheduling of a water-wind-solar integrated base, comprising the following specific steps: Taking the maximum wind and solar power generation consumption rate in the target area as the goal, an objective function is constructed; Obtain constraint conditions, solve the objective function based on system power balance constraints, hydropower constraints, wind and solar power generation constraints, and thermal power constraints to obtain an optimal scheduling model; Calculate the startup status of each unit based on the optimization scheduling model; Construct a state matrix according to the power-on state, and determine the system equivalent inertia constant according to the state matrix; Determine the inertia of the synchronous generator set of the hydroelectric generator set based on the system equivalent inertia constant; The scheduling of water-photovoltaic power generation is optimized based on the inertia of the synchronous generator set of the hydroelectric generator set.
[0007] Furthermore, the objective function of constructing the optimization scheduling model includes: ; In the formula, F is the objective function, T is the total duration, N w is the total number of wind power generation equipment at time t, N v is the total number of hydro-PV power generation equipment at time t, is the output of the i-th wind turbine generator set at time t, is the output of the i-th hydropower station at time t, is the maximum output of the i-th wind turbine generator set at time t, is the maximum output of the i-th hydro-PV station at time t.
[0008] Furthermore, the system power balance constraint includes: ; In the formula,N h，in is the total number of hydroelectric power generation equipment in the base during time period t, N w，in is the total number of wind power generation equipment in the base during time period t, N v，in is the total number of hydro-PV power generation equipment in the base within the time period t, N h，out is the total number of hydroelectric power generation equipment outside the base in time period t, N w，out is the total number of wind power generation equipment outside the base in time period t, N v，out is the total number of off-site photovoltaic power generation equipment in time period t, N g is the total number of thermal power generation equipment in time period t, The output of the hydroelectric generating unit in the i-th base in time period t, is the output of the i-th off-base hydroelectric generator unit in time period t, The hydropower output of the ith base in time period t is: The output of external hydropower at the i-th base in time period t is: is the thermal power output outside the base in time period t, is the total load demand in time period t.
[0009] Furthermore, the hydropower constraints include: ; In the formula, is the output of the hydroelectric generating unit in the ith base within the time period t, is the output of the i-th off-base hydroelectric generator unit in time period t, is the maximum output of the hydroelectric generating unit in the ith base within the time period t, is the maximum output of the i-th off-base hydroelectric generator unit in time period t, is the operating state of the hydropower generation equipment in the i-th base during time period t, usually in the shutdown state 0 or the operating state 1, is the operating state of the i-th off-base hydroelectric power generation equipment in time period t, usually the shutdown state 0 or the operating state 1, is the start time of the hydroelectric power generation equipment in the i-th base, is the start time of the hydroelectric power generation equipment outside the i-th base, is the closing time of the hydroelectric power generation equipment at the i-th input end, is the shutdown time of the thermal power generation equipment at the i-th output end.
[0010] Furthermore, the wind and solar power generation constraints include: ; In the formula, is the wind and solar power generation output of the i-th base in time period t, is the hydropower output of the ith base in time period t, is the maximum wind and solar power output of the ith base in time period t, is the maximum hydropower output of the ith base in time period t, is the wind and solar power generation output of the i-th base in time period t, is the wind power output outside the ith base in time period t, is the maximum wind power output outside the ith base in time period t, is the maximum photovoltaic output outside the i-th base in time period t.
[0011] Furthermore, the thermal power constraints, ; In the formula, is the operating state of the i-th thermal power unit, usually the shutdown state 0 or the operating state 1, is the minimum output of the ith thermal power unit, is the maximum output of the ith thermal power unit, is the start time of the i-th thermal power unit, is the shutdown time of the i-th thermal power unit, The downward climbing speed of the i-th thermal power unit, is the upward climbing speed of the i-th thermal power unit.
[0012] Furthermore, the system equivalent inertia constant calculation step includes: ; In the formula, H sys is the system equivalent inertia constant; S sys is the rated capacity of the power system, E rsg The rotational kinetic energy stored in the synchronous generator, E ssg Provides energy for virtual inertia control of new energy units. E load The energy provided for load inertia response.
[0013] Furthermore, the calculation step of determining the inertia of the synchronous generator set of the hydroelectric generator set includes: ; In the formula, H h is the inertia constant of the synchronous generator set of the hydropower unit, is the operating state of the hydropower generation equipment in the i-th base during time period t, usually in the shutdown state 0 or the operating state 1, is the installed capacity of the i-th hydropower generator, S sys is the total capacity of the system.
[0014] A second aspect of the present invention provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, a method for optimizing grid-connected scheduling of an integrated water, wind, and solar base is implemented.
[0015] A third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements a method for optimizing grid-connected scheduling of a water-wind-solar integrated base.
[0016] Compared with the prior art, the present invention has the following advantages and beneficial effects: A grid-connected optimization dispatching model for the integrated hydropower, wind and solar base was constructed to quantify the relationship between the hydropower startup plan and the output of each power source and the DC power transmission demand. The impact of the grid-connected mode, wind-solar ratio, and hydropower installed capacity on the optimized dispatching was evaluated, and the impact of the hydropower dispatching plan under different circumstances on the system equivalent inertia was evaluated. The grid-connected optimization dispatching can be optimized according to the impact to improve the dispatching capacity. With the goal of maximizing the wind and solar power consumption rate, a grid-connected optimization scheduling model for the integrated water, wind and solar power base was constructed to quantify the relationship between the hydropower startup plan and the output of each power source and the DC power transmission demand; The actual case analysis obtained the impact of grid connection mode, wind-solar ratio, hydropower installed capacity and other aspects on optimal scheduling, and evaluated the impact of hydropower scheduling plans under different circumstances on the system equivalent inertia. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other relevant drawings can be obtained based on these drawings without creative work. In the drawings: Figure 1 is an optimization flow chart in an embodiment of the present invention; Figure 2 It is a flow chart of the method for optimizing the grid-connected scheduling and system equivalent inertia evaluation of the water-wind-solar integrated base in an embodiment of the present invention; Figure 3 is a load demand curve in an embodiment of the present invention; Figure 4 is a hydropower output curve in an embodiment of the present invention; Figure 5 is a hydropower output curve in an embodiment of the present invention; Figure 6 is a hydropower output curve in an embodiment of the present invention; Figure 7 This is the load matching situation of the small coupling operation mode in the embodiment of the present invention; Figure 8 It is a startup plan of a hydropower unit in a small coupling operation mode in an embodiment of the present invention; Fig. 9 The load matching condition of the large coupling operation mode in the embodiment of the present invention; Fig.10 It is a startup plan of a hydropower unit in a large coupling operation mode in an embodiment of the present invention; Fig.11 is the equivalent inertia constant of the small coupling system in the embodiment of the present invention; Fig.12 is the equivalent inertia constant of the large coupling system in the embodiment of the present invention; Fig.13 It is the primary frequency regulation reserve capacity of the small coupled hydropower in the embodiment of the present invention; Fig.14 The primary frequency regulation reserve capacity of hydropower in the large coupling base in the embodiment of the present invention; Fig.15 is the equivalent inertia constant of the small coupling system when the wind-solar ratio is 6:1 in the embodiment of the present invention; Fig.16 is the equivalent inertia constant of the large coupling system when the wind-solar ratio is 6:1 in the embodiment of the present invention; Fig.17 is the equivalent inertia constant of the small coupling system when the wind-solar ratio is 3:4 in the embodiment of the present invention; Fig.18 is the equivalent inertia constant of the large coupling system when the wind-solar ratio is 3:4 in the embodiment of the present invention; Fig.19 is the equivalent inertia constant of the small coupling system when the wind-solar ratio is 1:6 in the embodiment of the present invention; Fig. 20 is the equivalent inertia constant of the large coupling system when the wind-solar ratio is 1:6 in the embodiment of the present invention; Fig.21 is the equivalent inertia constant of the small coupling system when the ratio of wind power to solar power is 1:1 after the hydropower adjustment in the embodiment of the present invention; Fig. 22 is the equivalent inertia constant of the large coupling system when the ratio of wind power to solar power is 1:1 after the hydropower adjustment in the embodiment of the present invention; Fig.23 is the equivalent inertia constant of the small coupling system when the ratio of wind power to solar power is 3:1 after the hydropower adjustment in the embodiment of the present invention; Fig.24 is the equivalent inertia constant of the large coupling system when the ratio of wind power to solar power is 3:1 after the hydropower adjustment in the embodiment of the present invention; Fig.25 is the equivalent inertia constant of the small coupling system when the wind-solar ratio is 1:3 after the hydropower adjustment in the embodiment of the present invention; Fig.26 is the equivalent inertia constant of the large coupling system when the wind-solar ratio is 1:3 after the hydropower adjustment in the embodiment of the present invention. DETAILED DESCRIPTION
[0018] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.
[0019] As a possible implementation, Figure 1 As shown, this embodiment provides a method for optimizing grid-connected scheduling of a water-wind-solar integrated base, including the following specific steps: constructing an objective function with the maximum total wind-solar power generation consumption rate in the target area as the goal; obtaining constraint conditions, solving the objective function based on system power balance constraints, hydropower constraints, wind-solar power generation constraints and thermal power constraints to obtain an optimization scheduling model; calculating the startup status of each unit based on the optimization scheduling model; constructing a state matrix according to the startup status, and determining the system equivalent inertia constant according to the state matrix; determining the inertia of the synchronous generator set of the hydropower generator set according to the system equivalent inertia constant; optimizing the scheduling of water-solar power generation based on the inertia of the synchronous generator set of the hydropower generator set. By constructing a grid-connected optimization scheduling model for a water-wind-solar integrated base, the relationship between the hydropower startup plan and the output of each power source and the DC power transmission demand is quantified, and the impact of the grid-connected mode, wind-solar ratio, and hydropower installed capacity on the optimization scheduling is evaluated. The impact of the hydropower scheduling plan under different conditions on the system equivalent inertia can be optimized according to the impact, and the scheduling capability can be improved.
[0020] In a possible implementation, in a new power system, improving the wind and solar power consumption rate is not only the key to improving the overall efficiency of the system, but also an important way to achieve the goal of sustainable energy development. Especially for the integrated water, wind and solar base, since it integrates multiple renewable energy sources such as hydropower, wind power and photovoltaic power generation, the optimization scheduling strategy of its grid-connected operation is particularly critical to improving the overall wind and solar power consumption rate. Therefore, this study sets the maximum total wind and solar power consumption rate inside and outside the base as the objective function of the optimization scheduling model, which includes: ; In the formula, F is the objective function, T is the total duration, N w is the total number of wind power generation equipment at time t, N v is the total number of hydro-PV power generation equipment at time t, is the output of the i-th wind turbine generator set at time t, is the output of the i-th hydropower station at time t, is the maximum output of the i-th wind turbine generator set at time t, is the maximum output of the i-th hydro-PV plant at time t.
[0021] In order to solve the objective function and obtain the optimal scheduling model, constraints are constructed and the objective function is solved based on the constraints, including system power balance constraints, hydropower constraints, wind and solar power generation constraints and thermal power constraints.
[0022] (1) System power balance constraints ; In the formula, N h，in is the total number of hydroelectric power generation equipment in the base during time period t, N w，in is the total number of wind power generation equipment in the base during time period t, N v，in is the total number of hydro-PV power generation equipment in the base within the time period t, N h，out is the total number of hydroelectric power generation equipment outside the base in time period t, N w，out is the total number of wind power generation equipment outside the base in time period t, N v，out is the total number of off-site photovoltaic power generation equipment in time period t, N g is the total number of thermal power generation equipment in time period t, The output of the hydroelectric generating unit in the i-th base in time period t, is the output of the i-th off-base hydroelectric generator unit in time period t, The hydropower output of the ith base in time period t is: The output of external hydropower at the i-th base in time period t is: is the thermal power output outside the base in time period t, is the total load demand in time period t.
[0023] (2) Hydropower constraints ; In the formula, is the output of the hydroelectric generating unit in the ith base within the time period t, is the output of the i-th off-base hydroelectric generator unit in time period t, is the maximum output of the hydroelectric generating unit in the ith base within the time period t, is the maximum output of the i-th off-base hydroelectric generator unit in time period t, is the operating state of the hydropower generation equipment in the i-th base during time period t, usually in the shutdown state 0 or the operating state 1, is the operating state of the i-th off-base hydroelectric power generation equipment in time period t, usually the shutdown state 0 or the operating state 1, is the start time of the hydroelectric power generation equipment in the i-th base, is the start time of the hydroelectric power generation equipment outside the i-th base, is the closing time of the hydroelectric power generation equipment at the i-th input end, is the shutdown time of the thermal power generation equipment at the i-th output end.
[0024] (3) Constraints on wind and solar power generation ; In the formula, is the wind and solar power generation output of the i-th base in time period t, is the hydropower output of the ith base in time period t, is the maximum wind and solar power output of the ith base in time period t, is the maximum hydropower output of the ith base in time period t, is the wind and solar power generation output of the i-th base in time period t, is the wind power output outside the ith base in time period t, is the maximum wind power output outside the ith base in time period t, is the maximum photovoltaic output outside the i-th base in time period t.
[0025] (4) Thermal power constraints ; In the formula, is the operating state of the i-th thermal power unit, usually the shutdown state 0 or the operating state 1, is the minimum output of the ith thermal power unit, is the maximum output of the ith thermal power unit, is the start time of the i-th thermal power unit, is the shutdown time of the i-th thermal power unit, The downward climbing speed of the i-th thermal power unit, is the upward climbing speed of the i-th thermal power unit.
[0026] In power systems, optimization scheduling models are often used to determine the startup state of each unit to minimize costs or meet specific operating constraints. The determination of the startup state usually involves consideration of constraints such as the unit's output, ramping capability, and minimum start-stop time. Based on these conditions, an optimization problem can be constructed, whose objective function may be to minimize the total cost, including the cost of power generation and the cost of start-stop. Once the startup state of the unit is determined, the state matrix can be constructed. The state matrix is a mathematical tool used to describe the behavior of the system in different states. In the context of power systems, the state matrix can be used to represent the combination of different units and their corresponding output power. The construction of the state matrix usually involves the analysis of the dynamic characteristics of the system, including the inertia, damping, and oscillation mode of the system. For the integrated water, wind, and solar base system, the equivalent inertia constant is an important parameter that characterizes the system's resistance to frequency changes. The determination of the equivalent inertia constant usually requires consideration of the inertia contribution of all generators in the system, as well as possible energy storage devices and load responses. Through the state matrix, the equivalent inertia constant of the system in a specific startup state can be determined. In actual operation, the startup state of the unit can be solved by an optimization algorithm, and then the state information can be used to construct a state matrix. The elements of the state matrix can be expressed as the output power of each unit or other related state variables. By analyzing the state matrix, the dynamic characteristics of the system can be further determined, including the equivalent inertia constant.
[0027] With the integration of renewable energy and power electronics technology, the sources of power system inertia have become diversified. New energy generation and regulated loads can provide additional virtual inertia support to the system through control strategies. The equivalent inertia of the power system has become a key indicator, which combines the responsiveness provided by traditional generators, new energy generation units, and loads to evaluate the system's resistance to frequency fluctuations. The equivalent inertia constant reflects the overall inertia support and frequency stability capabilities of the system, among which traditional generators provide a solid inertia foundation, while new energy generators and regulated loads increase the adaptability of the system through advanced control technology. The system equivalent inertia constant is as follows: ; In the formula, H sys is the system equivalent inertia constant; S sys is the rated capacity of the power system, E rsg The rotational kinetic energy stored in the synchronous generator, E ssg Provides energy for virtual inertia control of new energy units. Eload The energy provided for load inertia response.
[0028] In the power system, the inertia on the load side refers to the equipment and loads that are directly connected to the power grid and can react when the frequency changes. This type of equipment mainly includes asynchronous motors of various sizes, which can use their own rotational inertia to temporarily resist the change in speed when the power system frequency changes, thereby supporting the system frequency for a short time. On the other hand, static loads, such as lighting, heaters, etc., without obvious mechanical rotating parts, will also indirectly affect the frequency stability of the power grid due to the fluctuation of the power grid voltage. For example, when the voltage drops, the power demand of the static load will decrease, thereby reducing the burden on the power supply system. In addition, the current power system is increasingly adopting demand response measures, using intelligent technology to remotely control large industrial loads or household appliances to adjust their power consumption and respond to frequency fluctuations in an immediate and targeted manner. This paper only considers the inertia of the synchronous generator set of the hydropower generator set in the base, so as to analyze the impact of the optimal scheduling of the unit on the system equivalent inertia. Therefore, the equivalent inertia constant of the system at each moment is the ratio of the inertia of each hydropower unit to the total installed capacity of the system as follows: ; In the formula, H h is the inertia constant of the synchronous generator set of the hydropower unit, is the operating state of the hydropower generation equipment in the i-th base during time period t, usually in the shutdown state 0 or the operating state 1, is the installed capacity of the i-th hydropower generator, S sys is the total capacity of the system.
[0029] As a possible implementation method, this embodiment provides an electronic device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, a method for optimizing the grid-connected scheduling of an integrated water, wind, and solar base is implemented.
[0030] As a possible implementation method, this embodiment provides a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, a method for optimizing the grid-connected scheduling of a water-wind-solar integrated base is implemented.
[0031] As a possible implementation, Figure 2 As shown, this embodiment provides an actual data analysis example of a water-wind-solar integrated base in Sichuan Province. The installed capacity of wind power generation in the base is 2 million kilowatts; the installed capacity of photovoltaic power generation is 1.5 million kilowatts; the installed capacity of hydropower generation is 8.73 million kilowatts. The hydropower generation system in the base is composed of 16 hydropower stations. The specific parameters are shown in Table 1.
[0032] Table 1 Hydropower installed capacity in the base ; The installed capacity of wind power generation outside the base is 5 million kilowatts; the installed capacity of photovoltaic power generation is 3 million kilowatts; the installed capacity of hydropower generation is 80.74 million kilowatts; and the installed capacity of photovoltaic thermal power generation is 18.25 million kilowatts. The small coupling operation mode of water, wind and light integration is named small coupling operation mode, and its DC power transmission demand is 11 million kilowatts; the large coupling operation mode of water, wind and light integration base and power source outside the base is named large coupling operation mode, and its overall DC power transmission demand is 42 million kilowatts. The output and load demand curves of each power source adopt the historical data of Sichuan Province. The specific curves are as follows Figure 3-Figure 6 Shown (2) Impact of operating mode on startup plan and system equivalent inertia Firstly, the unit startup plan under the small coupling operation mode is optimized and calculated. Figure 7 The matching between the output of each power source and the load after the optimization calculation is shown. It can be seen that the overall output meets the demand for external power transmission very well. At the same time, the startup plan results of the base hydropower units are as follows: Figure 8 At this time, the wind and solar power consumption rate is 84.83%.
[0033] Secondly, optimize the unit startup plan under the large coupling operation mode. Fig. 9 After the optimization calculation, the output of each power source meets the demand for external power transmission. At the same time, the startup plan results of the base hydropower units are as follows: Fig.10 At this time, the wind and solar power consumption rate is 83.45%.
[0034] After the unit startup plan is calculated, the system equivalent inertia constants of the small coupling operation mode and the large coupling operation mode are calculated respectively. The results are as follows: Fig.11 and Fig.12 As shown in the figure, when the large coupling operation mode is used, the system equivalent inertia constant increases significantly, which is caused by the increase in the number of hydropower units in operation. In general, the primary frequency regulation reserve capacity of hydropower is larger during large coupling operation, which is due to the fact that more hydropower units are in operation at this time. Due to the difference in the number of hydropower units in operation, the primary frequency regulation reserve capacity of hydropower under small coupling is generally smaller than the value under large coupling operation mode. This shows that the large coupling operation mode of integrated water, wind and solar power has a stronger system frequency stability support capability than the small coupling mode.
[0035] In addition to the inertial response stage, the primary frequency regulation is also particularly important for the frequency response of the power system. The core purpose of primary frequency regulation is to suppress the deviation of the system frequency and achieve an immediate balance between load and supply by adjusting the output of the generator set. The strength of the primary frequency regulation capability mainly depends on the primary frequency regulation reserve capacity that each unit can provide. The reserve capacity can be defined as the difference between the maximum available output and the real-time output of the starting generator set. The primary frequency regulation reserve capacity of the hydro-wind-solar integrated base at each time is calculated as follows: Fig.13 and Fig.14 shown.
[0036] From the results in the figure, we can see that in most cases, the primary frequency regulation reserve capacity of hydropower is larger during large coupling operation. This is because more hydropower units are started at this time, which is similar to the inertia constant results above. The difference is that Fig.11 The equivalent inertia constant of the base does not appear when the small coupling is running, but Fig.13 During small and medium-sized coupling operation, the primary frequency regulation reserve capacity of hydropower is 0 at many times, and the times when the primary frequency regulation reserve capacity is 0 are more frequent than during large coupling operation, indicating that the large-scale coupling operation mode of integrated hydropower, wind and solar power will improve the primary frequency regulation capability of the system to a certain extent.
[0037] (3) Impact of wind and solar power ratio on startup plan and system equivalent inertia As an advanced model of new energy power generation system, the integrated water, wind and solar base integrates hydropower, wind power and solar power, realizing the maximization of energy production and the optimization of resource utilization. In the planning and design process of the integrated water, wind and solar base, the proportion of installed capacity of each energy source, that is, the proportion between hydropower, wind power and solar power, has a great impact on the system flexibility and optimized capacity results. Therefore, this paper adjusts the installed capacity of wind and solar power to further analyze the impact of the proportion of wind and solar power on the system. The wind power generation capacity is adjusted to 3 million kilowatts, the photovoltaic power generation is adjusted to 500,000 kilowatts, and the hydropower generation capacity remains unchanged.
[0038] like Fig.15 As shown in the figure, when the wind-solar ratio is 6:1 and the system is in a small coupling mode, the equivalent inertia constant of the system at each moment is not much different from the actual boundary situation, but the equivalent inertia constant becomes smaller at some moments, such as the more concave part of the inertia curve at some moments from 2500 to 4000 hours. This shows that when the proportion of wind power is higher, it can make up for the uncertainty of photovoltaic power to a certain extent. At some moments that originally require more hydropower support, wind power can meet the support needs. Fig.16 As shown, when the wind-solar ratio is 6:1, under the large coupling operation mode, the equivalent inertia constant of the system at each moment of the water-wind-solar integrated base is also more concave.
[0039] The wind power generation capacity is adjusted to 1.5 million kilowatts, the photovoltaic power generation capacity is adjusted to 2 million kilowatts, and the hydropower generation capacity remains unchanged. Fig.17 As shown in the figure, when the proportion of photovoltaic power generation increases, the peak of the equivalent inertia constant curve of the small coupling operation mode system at each moment increases, such as from 2500 to 3000 hours. For example, from 5000 to 5500 hours, the original peak is stretched in the time domain. These all indicate that when the proportion of photovoltaic power generation increases, more times need to be supported by hydropower. Fig.18 As shown, Fig.18 The result is almost the same as the system inertia constant curve under the actual boundary condition, indicating that the change of wind-solar ratio in the integrated water-wind-solar base has a greater impact on the small coupling operation mode.
[0040] Further increase the proportion of photovoltaic power generation, adjust the wind power generation capacity to 500,000 kilowatts, photovoltaic power generation to 3 million kilowatts, and the hydropower generation capacity remains unchanged. Fig.19 As shown in the figure, when the proportion of photovoltaic power generation further increases, the equivalent inertia constant curve of the system in the small coupling operation mode at each moment increases significantly. For example, the average value of the equivalent inertia constant from 3000 to 4000 hours and 5000 to 7000 hours increases from about 4 to about 5, indicating that the uncertainty of photovoltaic power generation in this example is stronger, and more hydropower generation is needed to support the increase in the proportion of photovoltaic power generation. Fig. 20 As shown, the system inertia constant of the large-coupling operation mode has a certain increase but it is not particularly obvious. This is because the wind and solar installed capacity of the integrated water, wind and solar base is much smaller than the overall wind and solar installed capacity.
[0041] (4) Impact of hydropower installed capacity on startup plan and system equivalent inertia Removing the 48 MW hydroelectric unit is equivalent to reducing the proportion of hydroelectric power, while adjusting the wind power generation capacity to 2 million kilowatts and photovoltaic power generation to 1.98 million kilowatts. Fig.21 As shown in the figure, after the proportion of hydropower decreased, the equivalent inertia constant curve of the wind-solar small coupling operation mode system at each moment decreased as a whole. This is because the installed capacity of wind and solar power increased. In the inertia calculation formula, the installed capacity of wind and solar power is the denominator, so the curve decreased as a whole. At the same time, the peaks at some moments disappeared because the proportion of photovoltaic power increased, replacing hydropower for support at these moments. Fig. 22 As shown, Fig. 22 The results show that the equivalent inertia constant curve of the base system at each moment in the large-coupling operation mode also decreased as a whole, but there was little change in the local part of the curve, which is similar to the above results. The change in the proportion of wind and solar power within the base has little effect in the large-coupling operation mode.
[0042] Further adjust the ratio of wind and solar power, adjust the wind power generation capacity to 3 million kilowatts, and the photovoltaic power generation to 980,000 kilowatts. Fig.23As shown in the figure, after the proportion of hydropower decreases, the equivalent inertia constant curve of the system in the small coupling operation mode at each moment decreases as a whole, and the curve peaks decrease. Fig.24 As shown, Fig.24 The results show that the overall curve also decreases a bit in the large coupling operation mode, and there are more valleys.
[0043] The wind power generation capacity was adjusted to 980,000 kilowatts and the photovoltaic power generation capacity to 3 million kilowatts. Fig.25 , Fig.26 The results are similar to those of adjusting the proportion of wind and solar power without reducing hydropower. The mean value of the equivalent inertia constant of the small coupling operation curve increases from 3000 to 4000 hours and from 5000 to 7000 hours, but the difference is that the curve decreases as a whole, which is the same as the result of reducing hydropower mentioned above.
[0044] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.
Claims
1. A method for optimizing grid-connected scheduling of a water-wind-solar integrated base, characterized in that: include: The specific steps are as follows: Taking the maximum wind and solar power generation consumption rate in the target area as the goal, an objective function is constructed; Obtain constraint conditions, solve the objective function based on system power balance constraints, hydropower constraints, wind and solar power generation constraints, and thermal power constraints to obtain an optimal scheduling model; Calculate the startup status of each unit based on the optimization scheduling model; Construct a state matrix according to the power-on state, and determine the system equivalent inertia constant according to the state matrix; Determine the inertia of the synchronous generator set of the hydroelectric generator set based on the system equivalent inertia constant; The scheduling of water-photovoltaic power generation is optimized based on the inertia of the synchronous generator set of the hydroelectric generator set.
2. The method for optimizing grid-connected scheduling of a water-wind-solar integrated base according to claim 1, characterized in that: The objective function of constructing the optimization scheduling model includes: ； In the formula, F is the objective function, T is the total duration, N w is the total number of wind power generation equipment at time t, N v is the total number of hydro-PV power generation equipment at time t, is the output of the i-th wind turbine generator set at time t, is the output of the i-th hydropower station at time t, is the maximum output of the i-th wind turbine generator set at time t, is the maximum output of the i-th hydro-PV station at time t.
3. The method for optimizing grid-connected scheduling of a water-wind-solar integrated base according to claim 1, characterized in that: The system power balance constraint includes: ； In the formula, N h，in is the total number of hydroelectric power generation equipment in the base during time period t, N w，in is the total number of wind power generation equipment in the base during time period t, N v，in is the total number of hydro-PV power generation equipment in the base within the time period t, N h，out is the total number of hydroelectric power generation equipment outside the base in time period t, N w，out is the total number of wind power generation equipment outside the base in time period t, N v，out is the total number of off-site photovoltaic power generation equipment in time period t, N g is the total number of thermal power generation equipment in time period t, The output of the hydroelectric generating unit in the i-th base in time period t, is the output of the i-th off-base hydroelectric generator unit in time period t, The hydropower output of the ith base in time period t is: The output of external hydropower at the i-th base in time period t is: is the thermal power output outside the base in time period t, is the total load demand in time period t.
4. The method for optimizing grid-connected scheduling of a water-wind-solar integrated base according to claim 1, characterized in that: The hydropower constraints include: ； In the formula, is the output of the hydroelectric generating unit in the ith base within the time period t, is the output of the i-th off-base hydroelectric generator unit in time period t, is the maximum output of the hydroelectric generating unit in the ith base within the time period t, is the maximum output of the i-th off-base hydroelectric generator unit in time period t, is the operating state of the hydropower generation equipment in the i-th base during time period t, usually in the shutdown state 0 or the operating state 1, is the operating state of the i-th off-base hydroelectric power generation equipment in time period t, usually the shutdown state 0 or the operating state 1, is the start time of the hydroelectric power generation equipment in the i-th base, is the start time of the hydroelectric power generation equipment outside the i-th base, is the closing time of the hydroelectric power generation equipment at the i-th input end, is the shutdown time of the thermal power generation equipment at the i-th output end.
5. The method for optimizing grid-connected scheduling of a water-wind-solar integrated base according to claim 1, characterized in that: The wind and solar power generation constraints include: ； In the formula, is the wind and solar power generation output of the i-th base in time period t, is the hydropower output of the ith base in time period t, is the maximum wind and solar power output of the ith base in time period t, is the maximum hydropower output of the ith base in time period t, is the wind and solar power generation output of the i-th base in time period t, is the wind power output outside the ith base in time period t, is the maximum wind power output outside the ith base in time period t, is the maximum photovoltaic output outside the i-th base in time period t.
6. The method for optimizing grid-connected scheduling of a water-wind-solar integrated base according to claim 1, characterized in that: The thermal power constraints include: ； In the formula, is the operating state of the i-th thermal power unit, usually the shutdown state 0 or the operating state 1, is the minimum output of the ith thermal power unit, is the maximum output of the ith thermal power unit, is the start time of the i-th thermal power unit, is the shutdown time of the i-th thermal power unit, The downward climbing speed of the i-th thermal power unit, is the upward climbing speed of the i-th thermal power unit.
7. The method for optimizing grid-connected scheduling of a water-wind-solar integrated base according to claim 1, characterized in that: The system equivalent inertia constant calculation steps include: ； In the formula, H sys is the system equivalent inertia constant; S sys is the rated capacity of the power system, E rsg The rotational kinetic energy stored in the synchronous generator, E ssg Provides energy for virtual inertia control of new energy units. E load The energy provided for load inertia response.
8. The method for optimizing grid-connected scheduling of a water-wind-solar integrated base according to claim 1, characterized in that: The system equivalent inertia constant calculation steps include: ； In the formula, H h is the inertia constant of the synchronous generator set of the hydropower unit, is the operating state of the hydropower generation equipment in the i-th base during time period t, usually in the shutdown state 0 or the operating state 1, is the installed capacity of the i-th hydropower generator, S sys is the total capacity of the system.
9. An electronic device, comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method for optimizing grid-connected scheduling of a water-wind-solar integrated base as described in any one of claims 1 to 8 is implemented.
10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method for optimizing grid-connected scheduling of a water-wind-solar integrated base as described in any one of claims 1 to 8 is implemented.