Energy storage configuration method considering frequency safety and stability of power system

Abstract

The invention provides an energy storage configuration method considering frequency safety and stability of a power system, and the method comprises the steps: building an overall inertia model of the power system based on an inertia component of the power system after large-scale grid connection of new energy and an inertia control method of each component; the method comprises the following steps: based on inertia support and frequency response characteristics of a new energy large-scale grid-connected power system, establishing an overall primary frequency modulation power variation model of the power system in the inertia support and primary frequency modulation process; establishing a target function model with optimization of the operation cost, the new energy abandoning cost, the frequency modulation standby cost and the energy storage configuration cost of each unit as a target; based on the constructed model, constructing an operation model of the new energy large-scale grid-connected power system in the typical wind and light operation scene; and the operation model is solved, and the optimal energy storage configuration scheme suitable for the operation scene is determined, so that the economical efficiency of system operation can be greatly improved.

Description

Technical Field

[0001] The present disclosure relates to the technical field of renewable energy power generation, and in particular to an energy storage configuration method and device that takes into account the frequency safety and stability of a power system. Background Art

[0002] Due to the increasing shortage of global coal resources and environmental pollution, vigorously developing new energy has become a unified strategy and consistent measure for energy transformation and climate change response in various countries. In the context of large-scale new energy grid connection, since new energy is coupled with the power system through power electronic equipment and has the characteristic of "zero inertia", the inertia response ability of high-proportion new energy power system is weakened. In this case, the system's anti-disturbance stable support ability and frequency regulation ability are greatly reduced, and the power system is prone to load shedding and power outage accidents, causing serious consequences. Therefore, for power systems with large-scale new energy access, improving the system inertia level and optimizing the configuration of system inertia resources are crucial to improving the anti-interference ability of the power system and the safe and stable operation of the frequency. At present, the inertia control technology configured with energy storage equipment at new energy stations has become one of the effective means to improve the frequency regulation ability and inertia support ability of the power system.

[0003] There are few existing studies on the configuration of energy storage resources for the integration of large-scale renewable energy into power systems. Some studies focus on the inertia support of energy storage equipment to the system, and fail to fully utilize the inertia resources of renewable energy units. In addition, most of these studies focus on the configuration methods of energy storage for renewable energy sites, and fail to consider the application scenarios of renewable energy integration into power systems. Some studies also focus on the optimal scheduling of energy storage equipment for the system, but fail to consider the frequency security issues of power systems with a high proportion of renewable energy. Some studies have considered the frequency regulation effect of energy storage devices on power systems, but have insufficient understanding of the frequency response process when power systems are disturbed, and have failed to recognize the coordinated relationship between inertia support and frequency regulation. Summary of the invention

[0004] In response to the defects of the prior art, this application proposes a method for configuring energy storage that takes into account the frequency safety and stability of the power system, fully considers the inertia resources of each power unit in a high-proportion new energy power system, mathematically characterizes the coordination between system inertia support and frequency regulation, and studies the energy storage configuration of large-scale new energy grid-connected power systems that consider frequency safety.

[0005] According to a first aspect of the present disclosure, there is provided a method for energy storage configuration considering the frequency security and stability of a power system, the method comprising: Step S1: constructing an inertia model of the entire power system based on the inertia components of the power system after large-scale grid connection of new energy and the inertia control method of each component; Step S2: Based on the inertia support and frequency response characteristics of the large-scale grid-connected power system of new energy, a model of the power change of the overall primary frequency regulation of the power system during the inertia support and primary frequency regulation process is established; Step S3: Establishing an objective function model with the goal of optimizing the operating cost of each unit, the cost of abandoning new energy, the cost of frequency regulation and standby, and the cost of energy storage configuration; Step S4: Based on the models constructed in steps S1 to S3, an operation model of a power system with large-scale grid connection of new energy sources under a typical wind and solar operation scenario is constructed; Step S5: Solve the operation model of the power system with large-scale grid-connected renewable energy under the typical wind-solar operation scenario, and determine the optimal energy storage configuration solution suitable for the operation scenario.

[0006] According to the above aspects and any possible implementation, an implementation is further provided, wherein the inertia component and inertia control method of each component of the power system after large-scale grid connection of new energy are used to construct an inertia model of the power system as a whole, including: Based on the inertia components of the power system after large-scale grid connection of new energy and the inertia control methods of each component, a mathematical model of the inertia constant of thermal power units, wind turbines and energy storage equipment is established; Obtain the number of thermal power units, wind power units and the rated power of energy storage equipment; Based on the number of thermal power units and wind power units, the rated power of energy storage equipment and the mathematical models of inertia constants of the thermal power units, wind power units and energy storage equipment, an overall inertia model of the power system is constructed.

[0007] According to the above aspects and any possible implementation, an implementation is further provided, wherein the inertia model of the entire power system is: ; in, is the number of thermal power units, is the start / stop status of the kth thermal power unit at time t; is the number of wind turbines; is the rated power of the energy storage power station, is the inertia constant of the thermal power synchronous generator, is the rated power of the synchronous generator, is the inertia constant of a single fan at time t, is the rated power of a single unit, is the inertia constant of the energy storage equipment at time t, is the rated power of the energy storage equipment.

[0008] According to the above aspects and any possible implementation, an implementation is further provided, wherein the inertia support and frequency response characteristics of the large-scale grid-connected power system based on new energy are established in the process of inertia support and primary frequency regulation, and the power change model of the overall primary frequency regulation of the power system includes: Determine the power change of a single thermal power unit based on the inertia support and frequency response characteristics of large-scale grid-connected power systems with new energy sources , Single fan primary frequency modulation power change And the change of primary frequency regulation power of energy storage power station ; According to the power change of a single thermal power unit , Single fan primary frequency modulation power change And the change of primary frequency regulation power of energy storage power station , construct the overall primary frequency regulation power variation model of the power system.

[0009] According to the above aspects and any possible implementation, a further implementation is provided, wherein the expression of the power system overall primary frequency regulation power variation model is for: .

[0010] According to the above aspects and any possible implementation, an implementation is further provided, wherein the objective function model with the optimization of the operating cost of each unit, the cost of abandoning new energy, the cost of frequency regulation and standby, and the cost of energy storage configuration as the goal is: ; in, is the total cost of power system operation, is the occurrence probability of scenario s, and They are respectively the operating cost of thermal power plants and the cost of abandoning new energy under different scenarios. The cost of energy storage equipment.

[0011] As described above and any possible implementation method, an implementation method is further provided, wherein the operating constraints of the objective function include: overall operation constraints of the power system, operation constraints of thermal power units, operation constraints of new energy sources, operation constraints of energy storage power stations, and frequency safety and stability constraints of the power system.

[0012] According to the above aspects and any possible implementation, an implementation is further provided, wherein based on the model constructed in step S1 to step S3, an operation model of a power system with large-scale grid-connected new energy under a typical wind and solar operation scenario is constructed, including: Obtain operating data of thermal power units, wind power units and energy storage devices; Generate a wind and solar power output scenario based on the operating data of the thermal power unit, wind power unit and energy storage device; Based on the wind and solar power output scenario and the constructed model, simulation software modeling is performed to obtain an operation model of a power system with large-scale grid connection of new energy under a typical wind and solar power operation scenario.

[0013] According to the above aspects and any possible implementation manner, an implementation manner is further provided, wherein the method further includes: Performing frequency verification on the optimal energy storage configuration scheme; If the frequency check is satisfied, the operating results of each unit and the energy storage configuration are output; otherwise, the system operation model is returned in the form of a penalty function until the frequency check is satisfied.

[0014] According to a second aspect of the present disclosure, there is provided an energy storage configuration device taking into account the frequency security and stability of a power system, the device comprising: A construction module is used to construct an inertia model of the entire power system based on the inertia components of the power system after large-scale grid connection of new energy and the inertia control methods of each component; The building module is also used to build a power change model of the overall primary frequency regulation of the power system based on the inertia support and frequency response characteristics of the large-scale grid-connected power system with new energy sources during the inertia support and primary frequency regulation process; The construction module is also used to establish an objective function model with the goal of optimizing the operating cost of each unit, the cost of abandoning new energy, the cost of frequency regulation and standby, and the cost of energy storage configuration; The construction module is also used to construct an operation model of a power system with large-scale grid connection of new energy under a typical wind and solar operation scenario based on the model constructed in steps S1 to S3; The solution module is used to solve the operation model of the power system with large-scale grid-connected renewable energy under the typical wind and solar operation scenario, and determine the optimal energy storage configuration solution suitable for the operation scenario.

[0015] According to a third aspect of the present disclosure, an electronic device is provided, comprising: a memory and a processor, wherein a computer program is stored in the memory, and when the processor executes the program, the method according to the first aspect of the present disclosure is implemented.

[0016] According to a fourth aspect of the present disclosure, a computer-readable storage medium is provided, on which a computer program is stored, and when the program is executed by a processor, the method according to the first aspect of the present disclosure is implemented.

[0017] Compared with the prior art, the present invention achieves the following beneficial effects: (1) The present invention provides a method for configuring energy storage that takes into account the frequency safety and stability of the power system. By establishing the mathematical model of the inertia constants of conventional thermal power units, fans and energy storage, the inertia model and frequency response model of the power system as a whole are constructed. Therefore, the frequency response model of the high-proportion new energy power system constructed by the present invention can combine the inertia support part with the frequency regulation part, and characterize the inertia support and frequency regulation process through a mathematical model, so that the system frequency response process is clearer, and the system frequency response can be intuitively analyzed only through a programming platform.

[0018] (2) The present invention uses the improved IEEE-30 node system as an example to construct an operation model of a power system with large-scale grid-connected renewable energy under a typical wind and solar scenario. Therefore, it is only necessary to change or increase or decrease the nodes in the node system and input the unit data under this scenario. At the same time, the energy storage equipment plays the role of peak shaving and valley filling as a regulating unit. By reducing the abandonment of renewable energy and smoothing the output of thermal power units, the economy of system operation can be greatly improved.

[0019] It should be understood that the contents described in the summary of the invention are not intended to limit the key or important features of the embodiments of the present disclosure, nor are they intended to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and other features, advantages and aspects of the embodiments of the present disclosure will become more apparent with reference to the following detailed description in conjunction with the accompanying drawings. The accompanying drawings are used to better understand the present solution and do not constitute a limitation of the present disclosure. In the accompanying drawings, the same or similar reference numerals represent the same or similar elements, among which: Figure 1 A flow chart of an energy storage configuration method considering the frequency security and stability of a power system according to an embodiment of the present disclosure is shown; Figure 2 shows the inertia support and frequency regulation curve of the power system according to an embodiment of the present disclosure; Figure 3 A frequency response model of a high-proportion new energy power system according to an embodiment of the present disclosure is shown; Figure 4 An improved IEEE-30 node wiring diagram according to an embodiment of the present disclosure is shown; Figure 5 Four wind and solar power output scene diagrams according to an embodiment of the present disclosure are shown; Figure 6 A diagram of the inertia demand of a power system without energy storage configuration according to an embodiment of the present disclosure is shown; Figure 7 A diagram showing a change in frequency index of a power system without energy storage configuration according to an embodiment of the present disclosure is shown; Figure 8 A diagram showing the inertia demand of a power system in a case where there is an energy storage configuration according to an embodiment of the present disclosure is shown; Fig. 9 The diagram shows the frequency index change of the power system in the case of energy storage configuration according to an embodiment of the present disclosure. Fig.10 A block diagram of an energy storage configuration device considering the frequency security and stability of a power system according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0022] In addition, the term "and / or" in this article is only a description of the association relationship between the associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0023] The following will describe an energy storage configuration method that takes into account the frequency safety and stability of the power system provided by the present disclosure in conjunction with the accompanying drawings.

[0024] Embodiment 1 like Figure 1 As shown, the embodiment of the present disclosure provides a flow chart of an energy storage configuration method considering the frequency security and stability of the power system, the method comprising: S1, based on the inertia components of the power system after large-scale grid connection of new energy and the inertia control methods of each component, construct an overall inertia model of the power system. In some embodiments, specifically, the inertia constant of the thermal power synchronous generator : ; Where, J is the moment of inertia; is the rotor angular velocity; is the rated power of the synchronous generator.

[0025] The wind turbine is controlled by a virtual synchronous machine. The inertia constant of a single wind turbine at time t is : ; in, is the energy released by the response inertia support of a single wind turbine at time t; The rated power of a single unit.

[0026] The expression is: ; in, is the energy released by the rotor kinetic energy during inertia response at time t; It is the mechanical energy lost due to the change in rotor speed when the fan inertia responds at time t.

[0027] The expression is: ; in, is the wind rotor tip speed; is the minimum grid-connected speed of the wind turbine; is the maximum speed of the fan rotor; is the headwind speed; Exit wind speed for frequency modulation; It is the lower limit of wind speed in the constant speed zone; is the cut-out wind speed of the fan.

[0028] The expression is: ; in, Capture mechanical power for wind turbines; is the mechanical power captured by the fan at the beginning of frequency modulation; T is the fan frequency modulation time; For the moment in FM; is the air density; is the impeller radius; is the tip speed ratio at the beginning of frequency modulation; represents the wind energy utilization coefficient; is the tip speed ratio that changes with the rotational speed; is the blade pitch angle; It is the rotor speed of the fan at the start of frequency modulation.

[0029] Photovoltaic inertia constant : ; Photovoltaic devices are stationary components and have no inertia.

[0030] The energy storage equipment adopts virtual synchronous machine control, and the inertia constant of energy storage : ; In the formula, is the output power of the new energy at time t; They are respectively the minimum and maximum output of new energy in one day.

[0031] Inertia of large-scale grid-connected power systems with new energy The expression is: ; in, is the number of thermal power units, is the start / stop status of the kth thermal power unit at time t; is the number of wind turbines; is the rated power of the energy storage power station.

[0032] Inertia constant of large-scale grid-connected power system with new energy The expression is: ; in, It is the rated power of the power system as a whole.

[0033] The expression is: ; in, is the rated power of the photovoltaic power station.

[0034] S2 is based on the inertia support and frequency response characteristics of large-scale grid-connected power systems with new energy, and establishes a model of the overall primary frequency regulation power change of the power system during the inertia support and primary frequency regulation process.

[0035] In some embodiments, the power system inertia support and frequency regulation characteristics are as follows: Figure 2 As shown: is the disturbance moment, at which the system performs inertia response, the support power is equal to the unbalanced power and the deficit power, at which the system frequency change rate RoCoF is a constant, and the frequency decreases linearly; This is the moment of a frequency modulation action. At this time, the unbalanced power of the system decreases, the absolute value of RoCoF decreases but is still less than 0, and the system frequency decreases slowly; At the lowest frequency point, the system unbalanced power is 0, RoCoF is 0, and the system frequency reaches the minimum point; At a later time, an additional frequency modulation is issued to make RoCoF greater than 0, and the system frequency rises back to near the steady-state deviation.

[0036] The power system frequency response model is as follows: Figure 3 As shown: The inertia support expression of the large-scale grid-connected power system of new energy is: ; in, The inertia support power of the system; is the rated frequency of the power system; is the system damping coefficient; is the system frequency deviation.

[0037] Discretize the system frequency response process, and the frequency modulation duration is , the step length is .

[0038] The power variation of primary frequency regulation of a single thermal power unit The expression is: ; in, is the primary frequency adjustment value of a single thermal power unit at point n; is the reheater time constant; is the work proportion coefficient of the high-pressure cylinder of the steam turbine; R is the speed governor adjustment coefficient; It is the FM dead zone; It is the load adjustment limit for thermal power units.

[0039] When the fan output power is greater than 20% of the rated power, the fan participates in frequency modulation. The power change of a single fan in one frequency modulation is The expression is: ; in, is the primary frequency adjustment amount of the fan at point n; is its first-order inertia time constant; is the primary frequency modulation coefficient; Adjust the limiter for its load.

[0040] Energy storage power station primary frequency regulation power change The expression is: ; in, is the first-order inertia time constant of the energy storage power station; is its primary frequency modulation coefficient.

[0041] The change of primary frequency regulation power of the power system as a whole The expression is: ; S3, establish an objective function model with the goal of optimizing the operating cost of each unit, the cost of abandoning new energy, the cost of frequency regulation and standby, and the cost of energy storage configuration.

[0042] In some embodiments, the objective function expression is: ; in, Total cost of operating the power system; is the occurrence probability of scenario s; and They are respectively the operating cost of thermal power plants and the cost of abandoning new energy under different scenarios; The cost of the energy storage power station.

[0043] Thermal power plant operation cost The expression is: ; in, is the coal consumption cost of unit k at time t, where To contribute to the unit, , , is the coal consumption coefficient; is the operating time of unit k in a day; are the startup / shutdown costs of unit k respectively.

[0044] Cost of abandoning new energy The expression is: ; in, is the unit abandonment cost; Capturing power for wind farms, is the actual output power of the wind farm; Capture power for photovoltaic stations, It is the actual output power of the photovoltaic station.

[0045] Energy storage power station cost The expression is: ; in, The total cost of energy storage investment and construction; Maintain the total cost of energy storage.

[0046] Total cost of energy storage investment and construction The expression is: ; in, is the investment cost per unit power of energy storage, is the investment cost per unit capacity of energy storage, is the energy storage capital recovery factor, is the energy storage investment discount rate, It is the service life of the energy storage power station.

[0047] Total cost of energy storage maintenance The expression is: ; in, It is the maintenance cost of energy storage unit.

[0048] The operating constraints of large-scale renewable energy grid-connected power systems taking into account frequency security and stability are divided into: (1) Overall operation constraints of the power system: The load balance constraint expression of the power system is: ; in, is the total system load; Output k for thermal power unit; Discharge power for energy storage power station; Charging power for energy storage power station.

[0049] The system power flow safety constraint expression is: ; in, is the power flow at the system node i at time t; The lower / upper limit of the power flow at the system node i respectively.

[0050] (2) Operation constraints of thermal power units: The upper and lower limit constraint expressions of thermal power unit output are: ; in, is the start / stop status of unit k at time t; is the lower / upper limit of the output of unit k.

[0051] The climbing constraint expression of thermal power unit is: ; in, is the down / up ramp rate of unit k.

[0052] The start and stop time constraint expression of thermal power units is: ; in, is the minimum start / shutdown time of unit k.

[0053] The hot standby constraint expression of thermal power units is: ; in, is the thermal standby coefficient of thermal power units.

[0054] (3) New energy operation constraints: The wind farm operation constraint expression is: ; in, is the available output power of the wind farm.

[0055] The operation constraint expression of the photovoltaic station is:

[0056] (4) Energy storage power station operation constraints: Energy storage output constraint expression: ; in, It is the discharging / charging status of the energy storage power station.

[0057] Energy storage real-time power constraint expression: ; in, The real-time capacity of the energy storage power station; The charging and discharging efficiency of the energy storage power station; It is the minimum capacity limit of the energy storage power station.

[0058] Energy storage frequency regulation capacity constraint expression: ; in, The total power of frequency regulation and inertia support at point n during frequency regulation of the energy storage power station; is the frequency change rate of the system at point n.

[0059] (5) Power system frequency security and stability constraints: System inertia requirement expression: ; in, is the system power shortage; Specifies the maximum rate of frequency change for the system.

[0060] System frequency safety constraint expression: ; in, is the maximum frequency deviation of the system; is the system steady-state frequency deviation.

[0061] S4, based on the model constructed in step S1 to step S3, construct an operation model of the power system with large-scale grid-connected new energy under a typical wind and solar operation scenario.

[0062] In some embodiments, an improved IEEE-30 node system is used to construct a high-proportion new energy power system, including 3 thermal power units, 2 photovoltaic stations, 1 wind farm and 1 energy storage power station.

[0063] First, the data of thermal power, wind power, photovoltaic power, etc. are processed to generate wind and solar power output scenarios; then the expressions constructed in steps S1 to S3 are modeled by simulation software to obtain the operation model of the power system with large-scale grid-connected new energy under typical wind and solar power operation scenarios.

[0064] S5, solving the operation model of the power system with large-scale grid-connected renewable energy under the typical wind and solar operation scenario, and determining the optimal energy storage configuration solution suitable for the operation scenario.

[0065] In some embodiments, in order to verify the feasibility of the scheme, it is necessary to further perform frequency verification on the optimal energy storage configuration scheme; if the frequency verification is met, the operation results of each unit and the energy storage configuration are output, otherwise, the system operation model is returned in the form of a penalty function until the frequency verification is met.

[0066] Embodiment 2 In order for those skilled in the art to better understand the present invention, a specific embodiment is described below: This embodiment takes an improved IEEE-30 node system as an example. Figure 4 As shown in Figure 1, the system includes 3 thermal power units, 2 photovoltaic stations, 1 wind farm and a storage power station. The rated power of the photovoltaic station at node 8 is 125MW, the rated power of the photovoltaic station at node 23 is 100MW, and the rated power of the wind farm at node 11 is 75MW.

[0067] The parameters of the thermal power unit are shown in Table 1; Table 1

[0068] The fan parameters are shown in Table 2: Table 2

[0069] The primary frequency regulation parameters of each unit are shown in Table 3: Table 3

[0070] The economic parameters of power system operation are shown in Table 4: Table 4

[0071] 4 wind and solar power output scenarios such as Figure 5As shown in the figure, taking 10% of the real-time load as a disturbance, the system frequency indicators are: system rated power is 50Hz; system maximum frequency change rate is 1Hz / s; system maximum frequency deviation is 0.5Hz; steady-state frequency deviation is 0.2Hz.

[0072] The power range of the energy storage optimization design is set to 10%~30% of the total rated power of new energy, and the capacity range is constrained to 2~4 times the power, ensuring that the energy storage power station can operate for a minimum of 2 hours. The optimal energy storage configuration is: the energy storage rated power is 87.94MW, and the rated capacity is 351.77MW.h. The economic performance of the system before and after optimization is shown in Table 5.

[0073] Table 5

[0074] From the data in Table 2, it can be seen that the economy of the system is greatly improved after the configuration of energy storage. This is because the energy storage power station makes full use of new energy resources and plays a role in peak shaving and valley filling, reducing the cost of abandoning new energy and the coal consumption cost of thermal power units.

[0075] Analyze the inertia demand diagram and frequency index change diagram of the power system without energy storage configuration, such as Figure 6 , 7 As shown, the inertia provided in scenarios 2 and 3 cannot meet the inertia requirement, and the system frequency is seriously unstable. It can be obtained that the larger the system inertia, the stronger the system anti-interference ability and the slower the frequency change; the smaller the inertia, the weaker the system anti-interference ability and the faster the system frequency changes.

[0076] Analyze the inertia demand diagram and frequency index change diagram of the power system with energy storage configuration, such as Figure 8 , 9 As shown in the figure, after optimization, all scenarios meet the system inertia requirements. The unmet needs of scenarios 2 and 3 when there is no energy storage are compensated by energy storage. After configuring the energy storage power station, the system frequency regulation capability is greatly enhanced, and the frequency indicators of each scenario meet the system frequency requirements.

[0077] According to the embodiments of the present disclosure, the following technical effects are achieved: (1) The present invention provides a method for configuring energy storage that takes into account the frequency safety and stability of the power system. By establishing the mathematical model of the inertia constants of conventional thermal power units, fans and energy storage, the inertia model and frequency response model of the power system as a whole are constructed. Therefore, the frequency response model of the high-proportion new energy power system constructed by the present invention can combine the inertia support part with the frequency regulation part, and characterize the inertia support and frequency regulation process through a mathematical model, so that the system frequency response process is clearer, and the system frequency response can be intuitively analyzed only through a programming platform.

[0078] (2) The present invention uses the improved IEEE-30 node system as an example to construct an operation model of a large-scale grid-connected power system of new energy under a typical wind and solar scenario. Therefore, it is only necessary to change or increase or decrease the nodes in the node system and input the unit data under the scenario. At the same time, the energy storage equipment plays the role of peak shaving and valley filling as a regulating unit. By reducing the abandonment of new energy and smoothing the output of thermal power units, the economy of system operation can be greatly improved, and it can be applied to high-proportion new energy power systems in various scenarios.

[0079] It should be noted that, for the aforementioned method embodiments, for the sake of simplicity of description, they are all expressed as a series of action combinations, but those skilled in the art should be aware that the present disclosure is not limited by the described order of actions, because according to the present disclosure, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily required by the present disclosure.

[0080] The above is an introduction to the method embodiment. The following is a further explanation of the scheme disclosed in the present invention through an apparatus embodiment.

[0081] Fig.10 FIG. 1 is a block diagram of an energy storage configuration device considering the frequency security and stability of a power system according to an embodiment of the present disclosure. Fig.10 As shown, the device comprises: A construction module 1010 is used to construct an inertia model of the entire power system based on the inertia components of the power system after large-scale grid connection of new energy and the inertia control method of each component; The construction module 1010 is also used to establish a power variation model of the overall primary frequency regulation of the power system during the inertia support and primary frequency regulation process based on the inertia support and frequency response characteristics of the large-scale grid-connected power system with new energy; The construction module 1010 is also used to establish an objective function model with the optimization of the operating cost of each unit, the cost of abandoning new energy, the cost of frequency regulation and standby, and the cost of energy storage configuration as the goal; The construction module 1010 is further used to construct an operation model of a power system with large-scale grid connection of new energy under a typical wind and solar operation scenario based on the model constructed in steps S1 to S3; The solution module 1020 is used to solve the operation model of the power system with large-scale grid-connected renewable energy under the typical wind and solar operation scenario, and determine the best energy storage configuration solution suitable for the operation scenario.

[0082] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the described module can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here.

[0083] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps recorded in this disclosure can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of this disclosure can be achieved, and this document is not limited here.

[0084] The above specific implementations do not constitute a limitation on the protection scope of the present disclosure. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A method for configuring energy storage considering the frequency security and stability of a power system, characterized in that: include: Step S1: constructing an inertia model of the entire power system based on the inertia components of the power system after large-scale grid connection of new energy and the inertia control method of each component; Step S2: Based on the inertia support and frequency response characteristics of the large-scale grid-connected power system of new energy, a model of the power change of the overall primary frequency regulation of the power system during the inertia support and primary frequency regulation process is established; Step S3: Establishing an objective function model with the goal of optimizing the operating cost of each unit, the cost of abandoning new energy, the cost of frequency regulation and standby, and the cost of energy storage configuration; Step S4: Based on the models constructed in steps S1 to S3, an operation model of a power system with large-scale grid connection of new energy sources under a typical wind and solar operation scenario is constructed; Step S5: Solve the operation model of the power system with large-scale grid-connected renewable energy under the typical wind-solar operation scenario, and determine the optimal energy storage configuration solution suitable for the operation scenario.

2. The method according to claim 1, characterized in that The inertia components of the power system after large-scale grid connection of new energy and the inertia control method of each component are used to construct an inertia model of the power system as a whole, including: Based on the inertia components of the power system after large-scale grid connection of new energy and the inertia control methods of each component, a mathematical model of the inertia constant of thermal power units, wind turbines and energy storage equipment is established; Obtain the number of thermal power units, wind power units and the rated power of energy storage equipment; Based on the number of thermal power units and wind power units, the rated power of energy storage equipment and the mathematical model of inertia constants of the thermal power units, wind power units and energy storage equipment, an overall inertia model of the power system is constructed.

3. The method according to claim 2, characterized in that The inertia model of the power system as a whole is: ； in, is the number of thermal power units, is the start / stop status of the kth thermal power unit at time t; is the number of wind turbines; is the rated power of the energy storage power station, is the inertia constant of the thermal power synchronous generator, is the rated power of the synchronous generator, is the inertia constant of a single fan at time t, is the rated power of a single unit, is the inertia constant of the energy storage equipment at time t, is the rated power of the energy storage equipment.

4. The method according to claim 1, characterized in that: The inertia support and frequency response characteristics of the large-scale grid-connected power system based on new energy are established in the process of inertia support and primary frequency regulation, and the overall primary frequency regulation power variation model of the power system includes: Determine the power change of a single thermal power unit based on the inertia support and frequency response characteristics of large-scale grid-connected power systems with new energy sources , Single fan primary frequency modulation power change And the change of primary frequency regulation power of energy storage power station ; According to the power change of a single thermal power unit , Single fan primary frequency modulation power change And the change of primary frequency regulation power of energy storage power station , construct the overall primary frequency regulation power variation model of the power system.

5. The method according to claim 4, characterized in that The expression of the power system overall primary frequency regulation power variation model is for: 。 6. The method according to claim 1, characterized in that The objective function model with the optimization of the operating cost of each unit, the cost of abandoning new energy, the cost of frequency regulation and standby, and the cost of energy storage configuration as the goal is: ； in, is the total cost of power system operation, is the occurrence probability of scenario s, and They are respectively the operating cost of thermal power plants and the cost of abandoning new energy under different scenarios. The cost of energy storage equipment.

7. The method according to claim 6, characterized in that The operating constraints of the objective function include: overall operating constraints of the power system, operating constraints of thermal power units, operating constraints of new energy sources, operating constraints of energy storage power stations, and frequency safety and stability constraints of the power system.

8. The method according to claim 1, characterized in that The operation model of the power system with large-scale grid connection of new energy sources under a typical wind and solar operation scenario is constructed based on the model constructed in step S1 to step S3, including: Obtain operating data of thermal power units, wind power units and energy storage devices; Generate a wind and solar power output scenario based on the operating data of the thermal power unit, wind power unit and energy storage device; Based on the wind and solar power output scenario and the constructed model, simulation software modeling is performed to obtain an operation model of a power system with large-scale grid connection of new energy under a typical wind and solar power operation scenario.

9. The method according to claim 8, characterized in that The method further comprises: Performing frequency verification on the optimal energy storage configuration scheme; If the frequency check is satisfied, the operating results of each unit and the energy storage configuration are output; otherwise, the system operation model is returned in the form of a penalty function until the frequency check is satisfied.

10. An energy storage configuration device considering the frequency safety and stability of the power system, characterized in that: include: A construction module is used to construct an inertia model of the entire power system based on the inertia components of the power system after large-scale grid connection of new energy and the inertia control methods of each component; The building module is also used to build a power change model of the overall primary frequency regulation of the power system based on the inertia support and frequency response characteristics of the large-scale grid-connected power system with new energy sources during the inertia support and primary frequency regulation process; The construction module is also used to establish an objective function model with the goal of optimizing the operating cost of each unit, the cost of abandoning new energy, the cost of frequency regulation and standby, and the cost of energy storage configuration; The construction module is also used to construct an operation model of a power system with large-scale grid connection of new energy under a typical wind and solar operation scenario based on the model constructed in steps S1 to S3; The solution module is used to solve the operation model of the power system with large-scale grid-connected renewable energy under the typical wind and solar operation scenario, and determine the optimal energy storage configuration solution suitable for the operation scenario.

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