阅读说明：本技术 风电基地最大装机容量的确定方法、装置及存储介质 (Method and device for determining maximum installed capacity of wind power base and storage medium ) 是由 罗煦之 刘世宇 韩平 于 2018-08-02 设计创作，主要内容包括：本发明提供一种风电基地最大装机容量的确定方法、装置以及存储介质,风电基地连接于电力系统主网,风电基地包括至少一个风电机组,所述方法包括：获取风电基地的初始参数以及电力系统主网的典型运行方式和频率下限；根据初始参数和典型运行方式,所述电力系统主网的目标频率,所述目标频率为在各风电机组满负荷运行的情况下,风电基地发生校核故障时电力系统主网的频率,校核故障为致使风电基地中进入低电压穿越状态的风电机组的容量最大的故障；若目标频率低于频率下限,则减小风电基地的装机容量,直至目标频率高于或者等于频率下限时,确定最大装机容量等于减小后风电基地的装机容量。本发明实施例可以提升电力系统主网的经济性能。(The invention provides a method, a device and a storage medium for determining the maximum installed capacity of a wind power base, wherein the wind power base is connected with a main network of an electric power system and comprises at least one wind power unit, and the method comprises the following steps: acquiring initial parameters of a wind power base and a typical operation mode and a frequency lower limit of a main network of a power system; according to initial parameters and a typical operation mode, the target frequency of the main network of the power system is the frequency of the main network of the power system when the wind power base checks faults under the condition that each wind power unit runs at full load, and the checking faults are faults which enable the capacity of the wind power units entering a low-voltage ride-through state in the wind power base to be the maximum; and if the target frequency is lower than the lower frequency limit, reducing the installed capacity of the wind power base until the target frequency is higher than or equal to the lower frequency limit, and determining that the maximum installed capacity is equal to the reduced installed capacity of the wind power base. The embodiment of the invention can improve the economic performance of the main network of the power system.)

1. A method for determining the maximum installed capacity of a wind power base, said wind power base being connected to a main network of an electric power system, said wind power base comprising at least one wind turbine, said method comprising:

acquiring initial parameters of the wind power base, a typical operation mode and a frequency lower limit of a main network of the power system, wherein the initial parameters comprise installed capacity of the wind power base, a grid structure of the wind power base, a low voltage ride through action threshold value of each wind turbine, low voltage ride through power dropping characteristics of each wind turbine and low voltage ride through power recovery characteristics of each wind turbine;

determining a target frequency of the main network of the power system according to the initial parameters and the typical operation mode, wherein the target frequency is the frequency of the main network of the power system when the wind power base has a check fault under the condition that each wind power generator runs at full load, and the check fault is the fault which causes the maximum capacity of the wind power generator which enters a low-voltage ride-through state in the wind power base;

and if the target frequency is lower than the lower frequency limit, reducing the installed capacity of the wind power base until the target frequency is higher than or equal to the lower frequency limit, and determining that the maximum installed capacity is equal to the reduced installed capacity of the wind power base.

2. The method of claim 1, wherein the target frequency is a minimum of the frequency of the main grid of the power system during a low voltage ride through power recovery of the wind turbines in the event that each wind turbine is operating at full load and the calibration fault occurs.

3. The method of claim 1, wherein said step of determining a target frequency of said power system main grid based on said initial parameters and said typical operating mode comprises:

establishing a simulation system model according to the initial parameters and the typical operation mode, wherein the input of the simulation system model comprises the initial parameters and the typical operation mode, and the output of the simulation system model is the target frequency;

and determining the checking fault and the target frequency of the power system main network in the simulation system model when the checking fault occurs.

4. The method of claim 3, wherein if the target frequency is lower than the lower frequency limit, then reducing the installed capacity of the wind power base until the target frequency is higher than or equal to the lower frequency limit, and wherein the step of determining that the maximum installed capacity is equal to the reduced installed capacity of the wind power base comprises:

if the target frequency is lower than the lower frequency limit, reducing the installed capacity of a wind power base in the simulation system model by unit installed capacity each time by adopting an iterative algorithm until the target frequency of the main network of the power system in the simulation system model is higher than or equal to the lower frequency limit, and ending the iteration;

and determining that the maximum installed capacity is equal to the installed capacity of a wind power base in the simulation system model at the end of iteration.

5. The method of claim 3, wherein the step of determining a check fault of the simulation system model comprises:

respectively carrying out short-circuit fault simulation analysis on each line in the wind power base to obtain the total capacity of the wind turbine generator which enters a low-voltage ride-through state and corresponds to the short-circuit fault of each line;

and determining the short-circuit fault which corresponds to the maximum total capacity of the wind turbine generator set entering the low-voltage ride-through state as a check fault.

6. The method of claim 1, wherein the lower frequency limit is a minimum frequency at which the power system main grid is guaranteed to operate stably in a typical operation mode.

7. A device for determining the maximum installed capacity of a wind power base connected to a main network of an electric power system, said wind power base comprising at least one wind turbine, characterized in that said device comprises:

the acquisition module is used for acquiring initial parameters of the wind power base and typical operation modes and frequency lower limits of the main network of the power system, wherein the initial parameters comprise installed capacity of the wind power base, a grid structure of the wind power base, low voltage ride through action threshold values of the wind power generation sets, low voltage ride through power drop characteristics of the wind power generation sets and low voltage ride through power recovery characteristics of the wind power generation sets;

a first determining module, configured to determine a target frequency of the main network of the power system according to the initial parameters and the typical operation mode, where the target frequency is a frequency of the main network of the power system when a check fault occurs in the wind power base under a condition that each wind power generator runs at full load, and the check fault is a fault that causes a maximum capacity of a wind power generator in the wind power base that enters a low-voltage ride-through state;

and the second determination module is used for reducing the installed capacity of the wind power base if the target frequency is lower than the lower frequency limit until the target frequency is higher than or equal to the lower frequency limit, and determining that the maximum installed capacity is equal to the reduced installed capacity of the wind power base.

8. A device for determining the maximum installed capacity of a wind power base, which is characterized by comprising a memory, a processor and a computer program stored on the memory and capable of running on the processor, wherein the processor executes the computer program to realize the steps of the method for determining the maximum installed capacity of the wind power base according to any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that a computer program is stored on the computer-readable storage medium, which computer program, when being executed by a processor, carries out the steps in the method of determining the maximum installed capacity of a wind power base according to any one of claims 1 to 6.

Technical Field

The invention relates to the technical field of power grids, in particular to a method and a device for determining the maximum installed capacity of a wind power base and a storage medium.

Background

The new energy sources such as wind power and solar power generation have the advantages of economy and environmental protection, the occupation ratio of a new energy power supply in a power system is larger and larger along with the development of a new energy technology, however, along with the larger and larger scale of a wind power base, when the wind power base breaks down, a large number of wind power generation sets are likely to enter a low-voltage ride-through state, so that the active power output level of the wind power generation sets is greatly reduced, and the low-voltage ride-through state can be recovered to the normal active power output level after a long time.

In the related technology, after a large-scale wind turbine generator enters a low-voltage ride-through state, the active power output level of the wind turbine generator drops greatly, so that the main network of the power system has active vacancy, at the moment, in order to avoid a large-scale chain grid disconnection accident of a wind power base, safety control measures such as load shedding and the like cannot be taken, if the installed capacity of the wind power base is too large, the active vacancy of the main network of the power system is too large, the frequency of the main network of the power system drops to be lower than the lower limit frequency required by stability, a third wire defense measure action of the main network of the power system such as low-cycle load shedding and the like is further triggered, the stability of the main network of the power system is damaged, and huge economic loss is caused by load shedding.

Therefore, the economic loss is caused by the overlarge installed capacity of the wind power base in the related art.

Disclosure of Invention

The embodiment of the invention provides a method and a device for determining the maximum installed capacity of a wind power base and a storage medium, and aims to overcome the defect that economic loss is caused by the fact that the installed capacity of the wind power base is too large in the related art.

In order to solve the technical problem, the invention is realized as follows:

in a first aspect, an embodiment of the present invention provides a method for determining a maximum installed capacity of a wind power base, where the wind power base is connected to a main grid of an electric power system, the wind power base includes at least one wind turbine, and the method includes:

acquiring initial parameters of the wind power base, a typical operation mode and a frequency lower limit of a main network of the power system, wherein the initial parameters comprise installed capacity of the wind power base, a grid structure of the wind power base, a low voltage ride through action threshold value of each wind turbine, low voltage ride through power dropping characteristics of each wind turbine and low voltage ride through power recovery characteristics of each wind turbine;

determining a target frequency of the main network of the power system according to the initial parameters and the typical operation mode, wherein the target frequency is the frequency of the main network of the power system when the wind power base has a check fault under the condition that each wind power generator runs at full load, and the check fault is the fault which causes the maximum capacity of the wind power generator which enters a low-voltage ride-through state in the wind power base;

and if the target frequency is lower than the lower frequency limit, reducing the installed capacity of the wind power base until the target frequency is higher than or equal to the lower frequency limit, and determining that the maximum installed capacity is equal to the reduced installed capacity of the wind power base.

In a second aspect, an embodiment of the present invention further provides a device for determining a maximum installed capacity of a wind power base, where the wind power base is connected to a main grid of an electric power system, the wind power base includes at least one wind turbine, and the device includes:

the acquisition module is used for acquiring initial parameters of the wind power base and typical operation modes and frequency lower limits of the main network of the power system, wherein the initial parameters comprise installed capacity of the wind power base, a grid structure of the wind power base, low voltage ride through action threshold values of the wind power generation sets, low voltage ride through power drop characteristics of the wind power generation sets and low voltage ride through power recovery characteristics of the wind power generation sets;

a first determining module, configured to determine a target frequency of the main network of the power system according to the initial parameters and the typical operation mode, where the target frequency is a frequency of the main network of the power system when a check fault occurs in the wind power base under a condition that each wind power generator runs at full load, and the check fault is a fault that causes a maximum capacity of a wind power generator in the wind power base that enters a low-voltage ride-through state;

and the second determination module is used for reducing the installed capacity of the wind power base if the target frequency is lower than the lower frequency limit until the target frequency is higher than or equal to the lower frequency limit, and determining that the maximum installed capacity is equal to the reduced installed capacity of the wind power base.

In a third aspect, an embodiment of the present invention further provides a device for determining a maximum installed capacity of a wind power base, where the device includes: the method comprises a memory, a processor and a computer program stored on the memory and capable of running on the processor, wherein the processor executes the computer program to realize the steps in the method for determining the maximum installed capacity of the wind power base provided by the embodiment of the invention.

In a fourth aspect, the embodiment of the present invention further provides a computer-readable storage medium, where a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, the computer program implements the steps in the method for determining the maximum installed capacity of the wind power base provided by the embodiment of the present invention.

In the embodiment of the invention, the initial parameters of the wind power base and the typical operation mode and the lower frequency limit of the main network of the power system are obtained, and the target frequency of the main network of the power system is determined according to the initial parameters and the typical operation mode, wherein the target frequency is the frequency of the main network of the power system when the wind power base checks the fault under the condition that each wind power unit runs at full load, and the check fault is the fault which causes the maximum capacity of the wind power unit entering a low-voltage ride-through state in the wind power base; and if the target frequency is lower than the lower frequency limit, reducing the installed capacity of the wind power base until the target frequency is higher than or equal to the lower frequency limit, and determining that the maximum installed capacity is equal to the reduced installed capacity of the wind power base. Therefore, the installed capacity of the wind power base can be controlled, so that when a fault that the capacity of a wind turbine generator which causes the wind power base to enter a low-voltage ride-through state is the maximum occurs, the target frequency is ensured to be higher than or equal to the lower frequency limit, economic losses such as a load due to the fact that the installed capacity of the wind power base is too large are avoided, and the effect of improving the economic performance of the method for determining the maximum installed capacity of the wind power base is achieved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without inventive labor.

Fig. 1 is a flowchart of a method for determining a maximum installed capacity of a wind power base according to an embodiment of the present invention;

FIG. 2 is a flowchart of a method for determining the maximum installed capacity of a wind power base according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of grid structures of a main grid and a wind power base of an electric power system according to an embodiment of the present invention;

FIG. 4 is a flowchart of another method for determining the maximum installed capacity of a wind power base according to an embodiment of the present invention;

fig. 5 is a structural diagram of a device for determining the maximum installed capacity of a wind power base according to an embodiment of the present invention;

fig. 6 is a structural diagram of another device for determining the maximum installed capacity of a wind power base according to an embodiment of the present invention;

fig. 7 is a structural diagram of another device for determining the maximum installed capacity of a wind power base according to an embodiment of the present invention;

fig. 8 is a structural diagram of another device for determining the maximum installed capacity of a wind power base according to an embodiment of the present invention;

fig. 9 is a structural diagram of another device for determining the maximum installed capacity of a wind power base according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The method for determining the maximum installed capacity of the wind power base can be used for determining the maximum installed capacity of the wind power base, so that when the installed capacity of the wind power base is smaller than or equal to the maximum installed capacity, the frequency of a main network of a power system can not be reduced to an unacceptable level when the wind power base is checked to have a fault, or protective actions such as load shedding and the like are caused due to the reduction of the frequency of the main network of the power system, and therefore economic loss caused by low-frequency protective actions of the main network of the power system is reduced.

The checking fault is a fault which causes the maximum capacity of the wind turbine generator set which enters the low-voltage ride-through state in the wind power base, namely when other faults occur, the capacity of the fan resistor which enters the ride-through state is smaller than the capacity of the wind turbine generator set which enters the ride-through state when the checking fault occurs, and therefore the frequency of the main network of the power system which is lowered when other faults occur is lower than the frequency of the main network of the power system which is lowered when the checking fault occurs.

Referring to fig. 1, fig. 1 is a flowchart of a method for determining a maximum installed capacity of a wind power base according to an embodiment of the present invention, where the wind power base is connected to a main grid of an electric power system, and the wind power base includes at least one wind turbine. As shown in fig. 1, the method for determining the maximum installed capacity of the wind power base comprises the following steps:

step 101, obtaining initial parameters of the wind power base and a typical operation mode and a frequency lower limit of the main network of the power system, wherein the initial parameters comprise installed capacity of the wind power base, a grid structure of the wind power base, a low voltage ride through action threshold value of each wind turbine, a low voltage ride through power dropping characteristic of each wind turbine and a low voltage ride through power recovery characteristic of each wind turbine.

The typical operation mode of the power system main network is an operation mode used for determining the lower frequency limit of the power system main network and determining the target frequency in step 102 as a basis for calculation.

It should be noted that the typical operation mode may be any operation mode within the stable operation range of the power system main grid, or may be set as the worst operation mode according to the stability requirement required by the power system main grid.

For example: and taking the lowest load operation mode of the power system main network in a historical time period as a typical operation mode, wherein at the moment, the wind power base enters a voltage crossing state to have the largest influence on the frequency of the power system main network, so that the frequency reduction amplitude of the power system main network in the lowest load operation mode is the largest.

In this embodiment, the target frequency determined in the minimum load operation mode in step 102 may be lower than the target frequency in the high load operation mode, and it is ensured that the maximum installed capacity determined by using the method for determining the maximum installed capacity of the wind power base can ensure that the frequency of the main grid of the power system is higher than or equal to a certain level regardless of any other fault, so that the maximum installed capacity of the wind power base determined by using the method for determining the maximum installed capacity of the wind power base with the minimum load operation mode as the typical operation mode is reduced.

In addition, the lower frequency limit may be a lowest operation frequency determined according to an operation mode of the power system main grid, and if the operation frequency of the power system main grid is lower than the lower frequency limit, a third line-of-defense protection measure action such as low-cycle load shedding of the power system main grid may be caused, and a load may be cut off, thereby causing economic loss.

In this step, the initial parameters of the wind power base, the typical operation mode of the main network of the power system, and the lower frequency limit may be obtained, so as to provide a data basis for determining the target frequency in step 102.

And 102, determining a target frequency of the main network of the power system according to the initial parameters and the typical operation mode, wherein the target frequency is the frequency of the main network of the power system when the wind power base checks a fault under the condition that each wind power generator runs at full load, and the check fault is the fault which causes the maximum capacity of the wind power generator which enters a low-voltage ride-through state in the wind power base.

The method for determining the target frequency of the main network of the power system can be obtained by simulating and calculating by using a computer simulation system, and can also be determined by using a power system stability operation analysis operation method and the like.

In addition, after a check fault occurs, all or part of the wind turbines enter a low voltage ride through state, and output electric quantity is reduced, so that active power of a main network of the power system is insufficient, the frequency of the main network of the power system is reduced, and the wind turbines need to be recovered from the low voltage ride through state to a normal operation state for a period of time.

It should be noted that, a fault causing the maximum capacity of the wind turbine generator set entering the low-voltage ride-through state in the wind power base is used as a check fault, and the check fault is used to determine a target fault, so that when another fault occurs, the frequency of the main grid of the power system is higher than the target frequency, thereby providing a basis for determining the maximum installed capacity by comparing the lowest target frequency with the lower frequency limit in step 103.

In this step, the initial parameters and the typical operation mode obtained in step 101 are adopted, and the fault causing the maximum capacity of the wind turbine generator set entering the low-voltage ride-through state in the wind power base is used as a check fault, so that the target frequency is determined, and it can be ensured that when other single faults occur, the capacity of the wind turbine generator set entering the low-voltage ride-through state is smaller than the capacity of the wind turbine generator set entering the low-voltage ride-through state when the check fault occurs, so that the target frequency determined by taking the fault causing the maximum capacity of the wind turbine generator set entering the low-voltage ride-through state as an operation basis is the lowest frequency of the main network of the power system when the single fault occurs in the wind power base, and thus the reliability of the maximum installed capacity determined in step 103 is.

And 103, if the target frequency is lower than the lower frequency limit, reducing the installed capacity of the wind power base until the target frequency is higher than or equal to the lower frequency limit, and determining that the maximum installed capacity is equal to the installed capacity of the wind power base after reduction.

If the target frequency is higher than or equal to the lower frequency limit, it can be determined that the installed capacity of the wind power base is within an allowable range of the maximum installed scale, that is, the installed capacity of the wind power base is smaller than or equal to the maximum installed capacity.

It should be noted that, in the case that the target frequency is lower than the lower frequency limit, the installed capacity of the wind power base is reduced, and the target frequency of the main grid of the power system is determined again according to the reduced installed capacity and the typical operation mode, which may be an iterative calculation process, for example: if the installed capacity of the wind power base is equal to 300MW and the determined target frequency is lower than the lower frequency limit, the installed capacity of the wind power base is reduced by 10MW each time, the target frequency determined by the method in the step 102 is adopted when the installed capacity of the wind power base is respectively equal to 290MW, 280MW and 270MW, and if the installed capacity of the wind power base is equal to 270MW and the determined target frequency is higher than or equal to the lower frequency limit, iteration is stopped, and the maximum installed capacity is determined to be equal to 270 MW.

Of course, the installed capacity reduced each time in the above iterative calculation process may also be any other value.

In addition, when the target frequency is lower than the lower frequency limit, the installed capacity of the wind power base is reduced, and the target frequency of the main grid of the power system is determined again according to the reduced installed capacity and the typical operation mode, in the process, the amount of reduction of the installed capacity of the wind power base may not be fixed, for example: when the difference between the target frequency and the lower frequency limit is large, the reduction amount of the installed capacity of the wind power base is also large, and when the difference between the target frequency and the lower frequency limit is small, the reduction amount of the installed capacity of the wind power base is also small, so that the number of iterations is reduced.

In this step, by comparing the magnitude relationship between the target frequency and the lower frequency limit, when the target frequency is higher than or equal to the lower frequency limit, the maximum installed capacity can be determined.

In the embodiment of the invention, the initial parameters of the wind power base and the typical operation mode and the lower frequency limit of the main network of the power system are obtained, and the target frequency of the main network of the power system is determined according to the initial parameters and the typical operation mode, wherein the target frequency is the frequency of the main network of the power system when the wind power base checks the fault under the condition that each wind power unit runs at full load, and the check fault is the fault which causes the maximum capacity of the wind power unit entering a low-voltage ride-through state in the wind power base; and if the target frequency is lower than the lower frequency limit, reducing the installed capacity of the wind power base until the target frequency is higher than or equal to the lower frequency limit, and determining that the maximum installed capacity is equal to the reduced installed capacity of the wind power base. Therefore, the installed capacity of the wind power base can be controlled, so that when a fault that the capacity of a wind turbine generator which causes the wind power base to enter a low-voltage ride-through state is the maximum occurs, the target frequency is ensured to be higher than or equal to the lower frequency limit, economic losses such as a load due to the fact that the installed capacity of the wind power base is too large are avoided, and the effect of improving the economic performance of the method for determining the maximum installed capacity of the wind power base is achieved.

Referring to fig. 2, fig. 2 is a flowchart of another method for determining the maximum installed capacity of a wind power base according to an embodiment of the present invention, where the wind power base is connected to a main grid of a power system, and the wind power base includes at least one wind turbine. As shown in fig. 2, the method for determining the maximum installed capacity of the wind power base comprises the following steps:

step 201, obtaining initial parameters of the wind power base, a typical operation mode and a frequency lower limit of the main network of the power system, wherein the initial parameters include an installed capacity of the wind power base, a grid structure of the wind power base, a low voltage ride through action threshold value of each wind turbine, a low voltage ride through power dropping characteristic of each wind turbine and a low voltage ride through power recovery characteristic of each wind turbine.

Step 202, establishing a simulation system model according to the initial parameters and the typical operation mode, wherein the input of the simulation system model comprises the initial parameters and the typical operation mode, and the output of the simulation system model is the target frequency.

The target frequency is the frequency of the main network of the power system when the wind power base checks faults under the condition that each wind power unit runs at full load, and the checking faults are faults which enable the capacity of the wind power units entering a low-voltage ride-through state in the wind power base to be the maximum.

In addition, since the stability requirement of the power system main network is high, in order to determine the above-mentioned check fault, the capacities of the wind turbines entering the low voltage ride through state after each fault occurs need to be compared, if each fault is checked in the actual main network of the power system, the safety stability of the power system main network is influenced and the economic loss is inevitably caused, so that the simulation system built by the computer system can be utilized by adopting the simulation system model, by inputting the initial parameters and the typical operation mode, it is possible to simulate the actual operation mode of the power system main grid and the wind power base, and thus, each fault can be simulated in the simulation system model respectively, the capacity of the wind turbine generator which enters a low-voltage ride-through state after each fault occurs is obtained, therefore, the fault with the maximum capacity of the wind turbine generator which enters the low-voltage ride-through state is selected as the check fault.

It should be noted that the input of the simulation system model may further include initial parameters, a typical operation mode, and a lower frequency limit, and the output may be a maximum installed capacity of the wind power base, where the maximum installed capacity is determined by the method in steps 202 to 204, and is output.

In this step, a simulation system model is established to provide a basis for determining the check fault and the target frequency in step 203.

Step 203, determining the checking fault, and determining the target frequency of the main network of the power system in the simulation system model when the checking fault occurs.

Each fault in the wind power base can be input into the simulation system model respectively, so that the capacity of the wind power generator set which enters the low-voltage ride-through state when the fault occurs is obtained, and the fault corresponding to the maximum capacity of the wind power generator set which enters the low-voltage ride-through state is selected as a check fault.

Optionally, the target frequency is a minimum value of a frequency of the main network of the power system when each wind turbine runs at full load and the check fault occurs, and the wind turbine is in a low-voltage ride-through power recovery period.

In the step, in the process of determining the check fault and the target frequency by adopting the simulation system model, each fault can be simulated by utilizing the simulation system model, and the problems of stability reduction, economic loss and the like caused by direct short-circuit fault analysis by using the power system can be avoided.

And 204, if the target frequency is lower than the lower frequency limit, reducing the installed capacity of the wind power base until the target frequency is higher than or equal to the lower frequency limit, and determining that the maximum installed capacity is equal to the installed capacity of the wind power base after reduction.

As an optional implementation manner, if the target frequency is lower than the lower frequency limit, decreasing the installed capacity of the wind power base until the target frequency is higher than or equal to the lower frequency limit, and determining that the maximum installed capacity is equal to the reduced installed capacity of the wind power base includes:

if the target frequency is lower than the lower frequency limit, reducing the installed capacity of a wind power base in the simulation system model by unit installed capacity each time by adopting an iterative algorithm until the target frequency of the main network of the power system in the simulation system model is higher than or equal to the lower frequency limit, and ending the iteration;

and determining that the maximum installed capacity is equal to the installed capacity of a wind power base in the simulation system model at the end of iteration.

Wherein the formula P can be adopted_i＝P_i-1- Δ P, where i is a positive integer and P is a positive integer, iteratively calculating the maximum installed capacity_iAnd when the target frequency is lower than the lower frequency limit, performing the iterative calculation, and inputting the installed capacity obtained after the iteration into the simulation system model to obtain the target frequency matched with the installed capacity after the iteration.

In addition, the iterative calculation process may be repeated multiple times until the final target frequency is higher than or equal to the lower frequency limit of the main grid of the power system, the iteration is stopped, and the installed capacity matched with the target frequency higher than or equal to the lower frequency limit of the main grid of the power system is determined as the maximum installed capacity.

In this embodiment, when the target frequency is lower than the lower frequency limit, the installed capacity of the wind power base can be gradually reduced by an iterative calculation method, so that the installed capacity matched with the target frequency higher than or equal to the lower frequency limit is the maximum installed capacity of the wind power base.

As an optional implementation manner, the step of determining a check fault of the simulation system model includes:

respectively carrying out short-circuit fault simulation analysis on each line in the wind power base to obtain the total capacity of the wind turbine generator which enters a low-voltage ride-through state and corresponds to the short-circuit fault of each line;

and determining the short-circuit fault which corresponds to the maximum total capacity of the wind turbine generator set entering the low-voltage ride-through state as a check fault.

For example, as shown in fig. 3, the wind power base includes 6 wind power plants, and the wind power plants 2 to 6 are respectively connected to the main network of the power system through a double-loop between the wind power plant 1 and the main network of the power system, so that the wind power base includes 7 lines, and the checking fault can be determined in the following manner:

respectively analyzing short-circuit faults of 7 lines in the graph 3, and obtaining the capacity of the wind turbine generator which enters a low-voltage ride-through state after each fault occurs;

and when the short-circuit fault of the line L1 is determined to occur, the capacity of the wind turbine generator which enters the low-voltage ride-through state is the maximum, and the short-circuit fault of the line L1 is determined to be a check fault.

In this embodiment, short-circuit fault analysis may be performed on each line, so as to obtain the capacity of the wind turbine generator that enters the low-voltage ride-through state when each line is short-circuited, and determine the short-circuit fault corresponding to the maximum capacity as the check fault.

Optionally, the lower frequency limit is a minimum frequency at which the power system main network is ensured to operate stably in a typical operation mode.

For example, the lower frequency limit may also be a threshold value of a third protection action of the power system main grid, such as: and if the frequency of the main network of the power system is lower than or equal to the threshold value, the low-cycle load shedding protection action is carried out, so that part or all of the load is cut off.

In this embodiment, the lower frequency limit may be determined according to the minimum frequency of the stable operation of the main network of the power system, so that the wind turbine generator set entering the low-voltage ride-through state may not damage the stable operation of the main network of the power system when any fault occurs, only by ensuring that the installed capacity of the wind power base is less than or equal to the maximum installed capacity determined in steps 201 to 204.

In the embodiment of the invention, the simulation system model is adopted to determine the checking fault, and the target frequency is determined according to the checking fault, so that the maximum installed capacity of the wind power base can be obtained under the condition of not influencing the stable operation of the main network of the power system, and in the planning and construction process of the wind power base, the safe and stable operation of the main network of the power system can be ensured when the fault occurs only by ensuring that the installed capacity of the wind power base is less than or equal to the maximum installed capacity, and the actions of third protection such as low-cycle load shedding and the like are prevented from causing huge economic loss.

Referring to fig. 4, fig. 4 is a flowchart of another method for determining the maximum installed capacity of a wind power base, according to an embodiment of the present invention, where the wind power base is connected to a main grid of a power system, and the wind power base includes at least one wind turbine. As shown in fig. 4, the method for determining the maximum installed capacity of the wind power base includes the following steps:

step 401, establishing a simulation system model according to a typical mode and a lower frequency limit of the main network of the power system and initial parameters of the wind power base, wherein the initial parameters include an installed capacity of the wind power base, a grid structure of the wind power base, a low voltage ride through action threshold value of each wind power unit, a low voltage ride through power dropping characteristic of each wind power unit and a low voltage ride through power recovery characteristic of each wind power unit.

And step 402, respectively carrying out short-circuit fault simulation on all lines of the wind power base, and selecting the line short-circuit fault which causes the maximum-scale wind turbine generator to enter a low-voltage ride-through state as a check fault.

The line short-circuit fault which causes the maximum-scale wind turbine generator to enter the low-voltage ride-through state can also be understood as that the capacity of the wind turbine generator which enters the low-voltage ride-through state is the maximum when one line has the short-circuit fault.

And step 403, when the sum of the output electric quantities of the wind generation sets in the wind generation base is equal to the installed capacity of the wind generation base, performing checking fault simulation calculation, and determining the target frequency of the main network of the power system.

And 403, judging whether the target frequency of the main network of the power system is out of limit in the simulation process.

If the target frequency of the power system main network is out of limit in the simulation process, executing step 405, and if the target frequency of the power system main network is always within a reasonable range in the simulation process, executing step 406.

The target frequency of the main network of the power system is out of limit in the simulation process, and the minimum value of the frequency of the main network of the power system may be lower than the lower limit of the frequency of the main network of the power system in the process that the wind turbine generator recovers to the normal operation state from the low voltage ride through state.

In addition, the lower frequency limit may be a minimum frequency that ensures stable operation of the power system main grid.

In addition, the target frequency of the main network of the power system is always in a reasonable range in the simulation process, and the minimum value of the frequency of the main network of the power system may be higher than or equal to the lower limit of the frequency of the main network of the power system in the process that the wind turbine generator recovers to the normal operation state from the low voltage ride through state.

And 405, reducing the installed capacity of the wind power base until the target frequency is higher than or equal to the lower frequency limit, and determining that the maximum installed capacity is equal to the reduced installed capacity of the wind power base.

And 406, determining that the maximum installed capacity of the wind power base is equal to the installed capacity of the wind power base.

According to the embodiment of the invention, a simulation system model can be adopted to determine the checking fault of the main network of the power system, and the target frequency of the main network of the power system is determined according to the checking fault, so that the size relation between the target frequency and the lower frequency limit of the main network of the power system is compared, the installed capacity of the wind power base is properly adjusted, and the installed capacity of the wind power base corresponding to the target frequency which is finally higher than or equal to the lower frequency limit is determined as the maximum installed capacity of the wind power base, so that the safe and stable operation of the main network of the power system can be ensured under the condition that the installed capacity of the wind power generator set is smaller than the maximum installed capacity, and the economic loss caused by protection action due to the fact that the frequency of the main network of.

Referring to fig. 5, an embodiment of the present invention further provides a device 500 for determining a maximum installed capacity of a wind power base, where the wind power base is connected to a main grid of an electric power system, the wind power base includes at least one wind turbine, and the device 500 includes:

an obtaining module 501, configured to obtain initial parameters of the wind power base, and a typical operation mode and a lower frequency limit of the main network of the power system, where the initial parameters include an installed capacity of the wind power base, a grid structure of the wind power base, a low voltage ride through threshold of each wind turbine, a low voltage ride through power drop characteristic of each wind turbine, and a low voltage ride through power recovery characteristic of each wind turbine;

a first determining module 502, configured to determine a target frequency of the main network of the power system according to the initial parameters and the typical operation mode, where the target frequency is a frequency of the main network of the power system when a check fault occurs in the wind power base under a condition that each wind power generator runs at full load, and the check fault is a fault that causes a maximum capacity of a wind power generator in the wind power base that enters a low-voltage ride-through state;

a second determining module 503, configured to reduce the installed capacity of the wind power base if the target frequency is lower than the lower frequency limit, until the target frequency is higher than or equal to the lower frequency limit, and determine that the maximum installed capacity is equal to the reduced installed capacity of the wind power base.

Optionally, as shown in fig. 6, the first determining module 502 includes:

a modeling unit 5021, configured to establish a simulation system model according to the initial parameters and the typical operation mode, where inputs of the simulation system model include the initial parameters and the typical operation mode, and an output of the simulation system model is the target frequency;

the first determining unit 5022 is configured to determine the checking fault and a target frequency of a main network of the power system in the simulation system model when the checking fault occurs.

Optionally, as shown in fig. 7, the second determining module 503 includes:

an iteration unit 5031, configured to, if the target frequency is lower than the lower frequency limit, reduce the installed capacity of a wind power base in the simulation system model by a unit installed capacity each time by using an iteration algorithm, until the target frequency of the main grid of the power system in the simulation system model is higher than or equal to the lower frequency limit, and then end the iteration;

a second determining unit 5032, configured to determine that the maximum installed capacity is equal to the installed capacity of a wind power base in the simulation system model at the end of the iteration.

Optionally, as shown in fig. 8, the first determining unit 5022 includes:

the simulation subunit 50221 is used for performing short-circuit fault simulation analysis on each line in the wind power base to obtain the total capacity of the wind turbine generator which enters a low-voltage ride-through state and corresponds to the short-circuit fault of each line;

and the determining subunit 50222 is used for determining that the short-circuit fault corresponding to the maximum total capacity of the wind turbine generator set entering the low-voltage ride-through state is a check fault.

The device for determining the maximum installed capacity of the wind power base provided by the embodiment of the invention can realize each process in the method embodiment, and obtain the same beneficial effect, and for avoiding repetition, the repeated description is omitted.

Referring to fig. 9, fig. 9 is a structural diagram of another apparatus for determining the maximum installed capacity of a wind power base according to an embodiment of the present invention, and as shown in fig. 9, the apparatus includes: a memory 901, a processor 902, a transceiver 903, and a computer program stored on the memory 901 and executable on the processor 902, wherein:

the processor 902 is configured to read the program in the memory 901, and execute the following processes:

acquiring initial parameters of the wind power base, a typical operation mode and a frequency lower limit of a main network of the power system, wherein the initial parameters comprise installed capacity of the wind power base, a grid structure of the wind power base, a low voltage ride through action threshold value of each wind turbine, low voltage ride through power dropping characteristics of each wind turbine and low voltage ride through power recovery characteristics of each wind turbine;

determining a target frequency of the main network of the power system according to the initial parameters and the typical operation mode, wherein the target frequency is the frequency of the main network of the power system when the wind power base has a check fault under the condition that each wind power generator runs at full load, and the check fault is the fault which causes the maximum capacity of the wind power generator which enters a low-voltage ride-through state in the wind power base;

and if the target frequency is lower than the lower frequency limit, reducing the installed capacity of the wind power base until the target frequency is higher than or equal to the lower frequency limit, and determining that the maximum installed capacity is equal to the reduced installed capacity of the wind power base.

Optionally, the target frequency is a minimum value of a frequency of the main network of the power system when each wind turbine runs at full load and the check fault occurs, and the wind turbine is in a low-voltage ride-through power recovery period.

Optionally, the step performed by the processor 902 for determining the target frequency of the main network of the power system according to the initial parameters and the typical operation mode includes:

establishing a simulation system model according to the initial parameters and the typical operation mode, wherein the input of the simulation system model comprises the initial parameters and the typical operation mode, and the output of the simulation system model is the target frequency;

and determining the checking fault and the target frequency of the power system main network in the simulation system model when the checking fault occurs.

Optionally, the step, executed by the processor 902, of reducing the installed capacity of the wind power base if the target frequency is lower than the lower frequency limit until the target frequency is higher than or equal to the lower frequency limit, and determining that the maximum installed capacity is equal to the reduced installed capacity of the wind power base includes:

if the target frequency is lower than the lower frequency limit, reducing the installed capacity of a wind power base in the simulation system model by unit installed capacity each time by adopting an iterative algorithm until the target frequency of the main network of the power system in the simulation system model is higher than or equal to the lower frequency limit, and ending the iteration;

and determining that the maximum installed capacity is equal to the installed capacity of a wind power base in the simulation system model at the end of iteration.

Optionally, the step of determining the checking fault of the simulation system model executed by the processor 902 includes:

respectively carrying out short-circuit fault simulation analysis on each line in the wind power base to obtain the total capacity of the wind turbine generator which enters a low-voltage ride-through state and corresponds to the short-circuit fault of each line;

and determining the short-circuit fault which corresponds to the maximum total capacity of the wind turbine generator set entering the low-voltage ride-through state as a check fault.

Optionally, the lower frequency limit is a minimum frequency at which the power system main network is ensured to operate stably in a typical operation mode.

The device for determining the maximum installed capacity of the wind power base provided by the embodiment of the invention can realize each process in the method embodiment and achieve the same technical effect, and is not repeated here for avoiding repetition.

An embodiment of the present invention further provides a computer storage medium, where a computer program is stored on the computer readable storage medium, and when the computer program is executed by a processor, the steps in the method for determining the maximum installed capacity of a wind power base described above are implemented, and the same technical effects can be achieved, and are not described herein again to avoid repetition.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

Through the above description of the embodiments, those skilled in the art will clearly understand that the method of the above embodiments can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware, but in many cases, the former is a better implementation manner. Based on such understanding, the technical solutions of the present invention may be embodied in the form of a software product, which is stored in a storage medium (such as ROM/RAM, magnetic disk, optical disk) and includes instructions for enabling an electronic device (such as a mobile phone, a computer, a server, an air conditioner, or a network device) to execute the method according to the embodiments of the present invention.

While the present invention has been described with reference to the embodiments shown in the drawings, the present invention is not limited to the embodiments, which are illustrative and not restrictive, and it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention as defined in the appended claims.