Flywheel frequency modulation method and device based on similar solar photovoltaic power

Abstract

The invention provides a flywheel frequency modulation method and device based on similar sunlight photovoltaic power. The method comprises the following steps: selecting a plurality of time points in a day as basic value points; obtaining the irradiance of each basic value point of the to-be-predicted day based on weather forecast to form an irradiance vector of the to-be-predicted day; acquiring irradiance vectors of M * N historical days of M days adjacent to the to-be-predicted day and M days in the same period adjacent to N years; s historical days most conforming to the weather of the to-be-predicted day are selected from the irradiance vectors of the M * N historical days to serve as a preliminary to-be-selected day set, and P historical days with the minimum absolute value of the difference between the irradiance vector of each preliminary to-be-selected day and the irradiance vector of the to-be-predicted day serve as a to-be-selected similar day set; obtaining the irradiance vector of the to-be-predicted day and the irradiance gradient vector of each to-be-selected similar day based on the irradiance vector of the to-be-predicted day and the irradiance vector of each to-be-selected similar day; obtaining a difference vector between the irradiance gradient vector of the to-be-predicted day and the irradiance gradient vector of each to-be-selected similar day; selecting to-be-selected similar days corresponding to the K minimum difference vectors as a similar day set, and obtaining weighting coefficients corresponding to the K similar days; based on the weighting coefficients corresponding to the K similar days and the actual power values of the K similar days at each basic value point, obtaining the photovoltaic power generation power of each basic value point of the to-be-predicted day; and determining the rotating speed of the flywheel based on the photovoltaic power generation power of each basic value point of the to-be-predicted day so as to realize flywheel frequency modulation. The technical problem that in the prior art, a flywheel frequency modulation method is low in energy conversion efficiency can be solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of motor control, in particular to a flywheel frequency modulation method and device based on similar daily photovoltaic power. BACKGROUND

[0002] In recent years, renewable energy generation represented by photovoltaic power generation has developed rapidly, and photovoltaic power stations have been built in various places to utilize new energy. However, it is found in the use process that the power generated by the photovoltaic power station has great uncertainty due to the influence of the weather and environmental factors on the same day, which brings great inconvenience to the operation and dispatching of the entire photovoltaic power station.

[0003] The power grid usually needs to operate within a stable frequency range (usually 49.9-50.1 Hz), and because the power generation of the photovoltaic power station is affected by the weather, when the power generation of the photovoltaic power station decreases, the frequency of the power grid will be affected and decrease, and vice versa, when the power generation of the photovoltaic power station increases, the frequency of the power grid will be affected and increase, so it is necessary to add corresponding energy storage devices to solve the disadvantages of the current power station operation.

[0004] To balance the daily power unevenness of the photovoltaic power station, a flywheel energy storage motor system is a better solution. The system uses a large inertia rotor to realize a device for converting "kinetic energy" and "electric energy". In actual operation, it can drive the flywheel rotor to accelerate rotation to store electric energy, and can also convert the kinetic energy of the rotor into electric energy output to assist the photovoltaic power station to complete the frequency modulation work according to actual needs.

[0005] The current mainstream technology on the market is to use flywheels with batteries to directly participate in frequency modulation, and in the actual operation process of the photovoltaic power station, the daily required charging and discharging power has a great relationship with the weather of the day, and the power level is different under different weather, so it is not the best solution to make the flywheel run at high speed, and the energy conversion efficiency is low. SUMMARY

[0006] The present application provides a flywheel frequency modulation method and device based on similar daily photovoltaic power, which can solve the technical problem of low energy conversion efficiency of the flywheel frequency modulation method in the prior art.

[0007] According to one aspect of the present application, a flywheel frequency modulation method based on similar daily photovoltaic power is provided, the method comprising:

[0008] Selecting several time points in a day as base points;

[0009] Based on the weather forecast, the irradiance of each base point of the day to be predicted is obtained to form an irradiance vector of the day to be predicted;

[0010] acquire M*N historical day irradiance vectors of M days adjacent to the to-be-predicted day and M days of the same period of the adjacent N years;

[0011] select S historical days that are most consistent with the weather of the to-be-predicted day from the M*N historical day irradiance vectors as a preliminary to-be-selected day set, and select P historical days with the minimum absolute value of the difference between the irradiance vector of each preliminary to-be-selected day and the irradiance vector of the to-be-predicted day as a to-be-selected similar day set, wherein M*N>S>P;

[0012] acquire the irradiance gradient vector of the to-be-predicted day and the irradiance gradient vector of each to-be-selected similar day based on the irradiance vector of the to-be-predicted day and the irradiance vector of each to-be-selected similar day;

[0013] acquire the difference vector between the irradiance gradient vector of the to-be-predicted day and the irradiance gradient vector of each to-be-selected similar day;

[0014] select K to-be-selected similar days corresponding to the K smallest difference vectors as a similar day set, and acquire the weighting coefficients corresponding to the K similar days, wherein P>K;

[0015] acquire the photovoltaic power generation power of each base point of the to-be-predicted day based on the weighting coefficients corresponding to the K similar days and the actual power values of the K similar days at each base point;

[0016] determine the rotation speed of the flywheel based on the photovoltaic power generation power of each base point of the to-be-predicted day to realize flywheel frequency modulation.

[0017] Preferably, determining the rotation speed of the flywheel based on the photovoltaic power generation power of each base point of the to-be-predicted day to realize flywheel frequency modulation comprises:

[0018] acquire the frequency modulation required power curve of the to-be-predicted day based on the photovoltaic power generation power of each base point of the to-be-predicted day, and report it to the power mechanism;

[0019] the power mechanism generates a frequency modulation task based on the frequency modulation required power curve of the to-be-predicted day and issues it to the photovoltaic power plant;

[0020] the photovoltaic power plant adjusts the frequency modulation required power curve based on the real-time running state of the to-be-predicted day, determines the rotation speed of the flywheel based on the adjusted power curve, and thus controls the flywheel frequency modulation system to output the corresponding power.

[0021] Preferably, after the photovoltaic power plant adjusts the frequency modulation required power curve based on the real-time running state of the to-be-predicted day, determines the rotation speed of the flywheel based on the adjusted power curve, and thus controls the flywheel frequency modulation system to output the corresponding power, the method further comprises:

[0022] determine whether the flywheel working rotation speed is greater than a preset rotation speed at a preset time before the photovoltaic power plant exits operation;

[0023] In the case that the working rotating speed of the flywheel is greater than the preset rotating speed, the working rotating speed is reduced to below the preset rotating speed, so as to feedback the residual energy to the power grid.

[0024] Preferably, the weighting coefficients corresponding to the K similar days are obtained by the following formula:

[0025]

[0026] In the formula, θ i is the weighting coefficient corresponding to the i th similar day, x 0 (t) is the irradiance of the day to be predicted at the base point t, x i (t) is the irradiance of the i th similar day at the base point t, and K is the number of similar days.

[0027] Preferably, the photovoltaic power of each base point of the day to be predicted is obtained by the following formula:

[0028]

[0029] In the formula, P is the photovoltaic power of the current base point, θ i is the weighting coefficient corresponding to the i th similar day, P i is the photovoltaic power of the i th similar day at the current base point, and K is the number of similar days.

[0030] Preferably, the rotating speed of the flywheel is determined by the following formula:

[0031] P = an 2

[0032] In the formula, P is the photovoltaic power of the current base point, a is the rotating speed coefficient, and n is the rotating speed of the flywheel.

[0033] According to another aspect of the present application, a computer device is provided, which comprises a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements any of the above methods when executing the computer program.

[0034] By the technical scheme of the present application, the photovoltaic power of each base point of the day to be predicted is obtained based on the irradiance of each base point of the historical day and the day to be predicted, the rotating speed of the flywheel is obtained based on the photovoltaic power of each base point of the day to be predicted, and the operation mode of the flywheel is adjusted in real time according to the weather condition of the day, so as to output different power levels under different weather conditions, thereby reducing the precision and difficulty of the flywheel control and realizing the optimal solution of the rotating speed of the flywheel. BRIEF DESCRIPTION OF DRAWINGS

[0035] The accompanying drawings, which form part of this specification, are provided to further illustrate embodiments of the invention and, together with the textual description, explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0036] Figure 1 A flowchart of a flywheel frequency modulation method based on similar daily photovoltaic power provided according to an embodiment of the present invention is shown;

[0037] Figure 2 A flowchart for determining the flywheel speed according to an embodiment of the present invention is shown;

[0038] Figure 3 A schematic diagram of a flywheel frequency modulation system according to an embodiment of the present invention is shown;

[0039] Figure 4 A schematic diagram of a flywheel frequency modulation system participating in power grid frequency regulation according to an embodiment of the present invention is shown. Detailed Implementation

[0040] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0042] The relative arrangement of parts and steps illustrated in these embodiments and the numerical expressions and values are not intended to limit the scope of the present application unless otherwise specifically stated. At the same time, it should be understood that the sizes of the various parts shown in the drawings are not drawn in proportion to the actual proportions. The techniques, methods and devices known to those skilled in the relevant art can not be discussed in detail, but should be considered as part of the authorized description where appropriate. In all examples shown and discussed here, any specific value should be interpreted as merely exemplary, and not as a limitation. Therefore, other examples of exemplary embodiments can have different values. It should be noted that similar reference numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0043] As shown in Figure 1 The present application provides a flywheel frequency modulation method based on similar solar photovoltaic power, the method comprising:

[0044] S10, selecting several time points in a day as base points;

[0045] S20, obtaining the irradiance of each base point of the predicted day based on the weather forecast to form the irradiance vector of the predicted day;

[0046] S30, obtaining the irradiance vector of MxN historical days adjacent to the predicted day and the same period of M days adjacent to the N years;

[0047] S40, selecting S historical days most consistent with the predicted day from the irradiance vector of MxN historical days as a preliminary candidate day set, and selecting P historical days with the minimum absolute value of the difference between the irradiance vector of each preliminary candidate day and the irradiance vector of the predicted day as a candidate similar day set, wherein MxN>S>P;

[0048] S50, obtaining the irradiance gradient vector of the predicted day and the irradiance gradient vector of each candidate similar day based on the irradiance vector of the predicted day and the irradiance vector of each candidate similar day;

[0049] S60, obtaining the difference vector between the irradiance gradient vector of the predicted day and the irradiance gradient vector of each candidate similar day;

[0050] S70, selecting the candidate similar days corresponding to the K smallest difference vectors as the similar day set, and obtaining the weighting coefficients corresponding to the K similar days, wherein P>K;

[0051] S80, obtaining the photovoltaic power of each base point of the predicted day based on the weighting coefficients corresponding to the K similar days and the actual power values of the K similar days at each base point.

[0052] S90, determining the rotating speed of the flywheel based on the photovoltaic power at each base value point of the day to be predicted, so as to realize flywheel frequency modulation.

[0053] The present application obtains the photovoltaic power at each base value point of the day to be predicted based on the irradiance at each base value point of the historical day and the day to be predicted, and obtains the rotating speed of the flywheel based on the photovoltaic power at each base value point of the day to be predicted, and adjusts the flywheel operation mode in real time according to the weather condition of the day, so as to realize output of different power levels under different weather conditions, thereby reducing the precision and difficulty of flywheel control, and realizing the optimal solution of the rotating speed of the flywheel.

[0054] According to an embodiment of the present application, in S70 of the present application, the weighted coefficients corresponding to the K similar days are obtained by the following formula:

[0055]

[0056] In the formula, θ i is the weighted coefficient corresponding to the i th similar day, x 0 (t) is the irradiance of the day to be predicted at the base value point t, x i (t) is the irradiance of the i th similar day at the base value point t, and K is the number of similar days.

[0057] According to an embodiment of the present application, in S80 of the present application, the photovoltaic power at each base value point of the day to be predicted is obtained by the following formula:

[0058]

[0059] In the formula, P is the photovoltaic power at the current base value point, θ i is the weighted coefficient corresponding to the i th similar day, P i is the photovoltaic power of the i th similar day at the current base value point, and K is the number of similar days.

[0060] According to an embodiment of the present application, in S90 of the present application, the rotating speed of the flywheel is determined by the following formula:

[0061] P=an 2

[0062] In the formula, P is the photovoltaic power at the current base value point, a is the rotating speed coefficient, and n is the rotating speed of the flywheel.

[0063] Wherein, a is a fixed constant, the value of which is related to the specific application scenario, which can be divided into multiple speed intervals according to the demand, assuming that the peak speed of a flywheel motor is 5000r / min, the rated power is 2MW (the minimum speed requirement is 4000rpm), if the speed is too low, it cannot complete 2MW discharge, and if the speed is normal 5000r / min, the discharge power is too low, which will affect the efficiency of the flywheel system, according to the above problems, the flywheel can be divided into two discharge intervals, and the functions are shown in the following table.

[0064] Table 1 flywheel discharge interval

[0065] Operating speed Motor function Charge and discharge power 0-1000 rpm Standby speed-up Only charge function 1000-3000 rpm Speed-up and pre-stop 200 kW 3000-4000 rpm Charge and discharge 1 MW 4000-5000 rpm Charge and discharge 2 MW

[0066] According to an embodiment of the present application, in S90 of the present application, as shown in Figure 2 , the speed of the flywheel is determined based on the photovoltaic power generation power of each base point of the day to be predicted, to realize flywheel frequency modulation, which includes:

[0067] S91, based on the photovoltaic power generation power of each base point of the day to be predicted, the power curve required for frequency modulation of the day to be predicted is obtained and reported to the power mechanism;

[0068] S92, the power mechanism generates a frequency modulation task based on the power curve required for frequency modulation of the day to be predicted and issues it to the photovoltaic power plant;

[0069] S93, the photovoltaic power plant adjusts the power curve required for frequency modulation based on the real-time running state of the day to be predicted, determines the speed of the flywheel based on the adjusted power curve, and controls the flywheel frequency modulation system to output the corresponding power.

[0070] According to an embodiment of the present application, as shown in Figure 2 , after the photovoltaic power plant adjusts the power curve required for frequency modulation based on the real-time running state of the day to be predicted, determines the speed of the flywheel based on the adjusted power curve, and controls the flywheel frequency modulation system to output the corresponding power, the method further includes:

[0071] S94, at a preset time before the photovoltaic power plant exits operation, it is judged whether the flywheel working speed is greater than the preset speed; wherein, the preset time can be set to 5min, and the preset speed can be set to 1000rpm;

[0072] S95, in the case where the flywheel working speed is greater than the preset speed, the working speed is reduced to below the preset speed, so as to feedback the remaining energy to the power grid.

[0073] In this embodiment, the last step is the energy feedback step. At the end of each day, the system no longer needs to perform frequency adjustment tasks. If the flywheel speed is greater than 1000 rpm at this time, the system discharges a small amount of power to the power grid. This discharge process does not cause changes in the power grid frequency, thus improving energy utilization.

[0074] To gain a further understanding of the present invention, the following description is provided in conjunction with... Figures 1 to 4 The flywheel frequency modulation method based on similar daily photovoltaic power of the present invention will be described in detail.

[0075] In the actual operation of a photovoltaic power station, the daily required charging and discharging power is greatly influenced by the weather conditions. Power levels vary depending on the weather, and simply keeping the flywheel running at high speeds increases the precision and difficulty of control. Therefore, it is necessary to adjust the flywheel operating mode in real time based on the predicted frequency regulation power curve and the weather conditions of the day. This includes the following steps: Figures 1-2 As shown:

[0076] Step 1: Take the hourly times during the daily working hours of the photovoltaic power station (e.g., 6-18 in summer) as base points, and combine the daily weather forecast with the light intensity detection of the photovoltaic base to obtain the irradiance of each base point, forming the irradiance vector x0 for the day to be predicted.

[0077] Step 2: Extract historical irradiance data for the 15 days preceding the date to be predicted and the 15 days for the same period in the past three years, forming an irradiance vector x for 60 historical days. i ;

[0078] Step 3: Select the 20 historical days from the irradiance vectors of the 60 historical days that best match the weather of the day to be predicted as a preliminary candidate set. Then, calculate the absolute value Δx of the difference between the irradiance vector of each preliminary candidate day and the irradiance vector of the day to be predicted. i The 10 smallest historical days are selected as the set of similar days to be chosen; the absolute value is calculated as follows:

[0079] Δx i =|x0-x i | i = 1, ..., 10

[0080] Step 4: Based on the irradiance vector of the day to be predicted and the irradiance gradient vector of each candidate similar day, obtain the irradiance vector of the day to be predicted and the irradiance gradient vector of each candidate similar day; wherein, the irradiance gradient vector x′ is calculated using the following formula. i :

[0081] x′ i =[x i (7)-x i (6), x i (8)-x i(7),..., x i (18)-x i (17)] i=0, 1,..., 10

[0082] Step 5, obtain the difference vector Δx' of the irradiance gradient vector of the day to be predicted and the irradiance gradient vector of each candidate similar day respectively i ; wherein the difference vector is calculated by the following formula:

[0083] Δx' i = |x'0-x' i | i=1,..., 10

[0084] Step 6, sort the candidate similar days from small to large according to the absolute value of the difference vector of the irradiance gradient vector of the candidate similar day and the day to be predicted. Select the three smallest difference vectors corresponding to the candidate similar days as the similar day set, and obtain the weighted coefficients corresponding to the three similar days; wherein the weighted coefficient θ is calculated by the following formula: i :

[0085]

[0086] Step 7, based on the weighted coefficients corresponding to the three similar days and the actual power values of the three similar days at each base point, obtain the photovoltaic power at each base point of the day to be predicted; wherein the photovoltaic power P at each base point of the day to be predicted is calculated by the following formula:

[0087]

[0088] Step 8, the output power of the flywheel motor is positively related to the speed, and the output power P is proportional to the square of the speed n. The relationship between the discharge power P and the speed n is: P=an 2 ;

[0089] Step 9, based on the photovoltaic power at each base point of the day to be predicted, obtain the power curve required for frequency modulation of the day to be predicted, and report to the power mechanism;

[0090] Step 10, the power mechanism generates a frequency modulation task based on the power curve required for frequency modulation of the day to be predicted and issues it to the photovoltaic power station;

[0091] Step 11, the photovoltaic power station adjusts the power curve required for frequency modulation based on the real-time running state of the day to be predicted, determines the speed of the flywheel based on the adjusted power curve, and thus controls the flywheel frequency modulation system to output the corresponding power;

[0092] Step 12, 5 minutes before the photovoltaic power station exits operation, determine whether the flywheel working speed is greater than 1000 rpm;

[0093] Step 13, in the case that the working speed of the flywheel is greater than 1000 rpm, the working speed is reduced to below 1000 rpm to feed back the residual energy to the power grid.

[0094] Figure 3 The structural schematic diagram of the flywheel frequency modulation system is shown, Figure 4 The structural schematic diagram of the flywheel frequency modulation system participating in the frequency modulation of the power grid is shown. Figure 3 And Figure 4 As shown in the figure, the flywheel frequency modulation system contains key devices such as flywheel, braking resistance, circuit breaker, machine side converter, PCS and the like inside, and auxiliary devices are heat dissipation fans and the like, and the device has the following advantages compared with the current mainstream scheme:

[0095] 1. Simple and reliable control, the circuit breaker can ensure that the system failure does not affect the operation of the main grid;

[0096] 2. The overall operation mode adopts multiple power intervals combined with similar day power curves, and the operation mode can be adjusted in real time according to the local weather conditions to improve the energy conversion efficiency;

[0097] 3. It has AC-DC power conversion function, and can effectively complete the charging and discharging of the flywheel motor;

[0098] 4. It can complete the frequency modulation task of the photovoltaic power station, and can output power according to the frequency modulation demand of the power station;

[0099] 5. Discharge feedback is carried out before the power station exits operation, the residual power is fed back to the power grid, and the energy utilization efficiency is improved.

[0100] The application also provides a computer device, which comprises a memory, a processor, and a computer program stored in the memory and capable of running on the processor, and the processor implements the method described above when executing the computer program.

[0101] In summary, the application provides a flywheel frequency modulation method and device based on similar day photovoltaic power, obtains the photovoltaic power generation power of each base value point of the to-be-predicted day based on the irradiance of each base value point of the historical day and the to-be-predicted day, obtains the flywheel speed based on the photovoltaic power generation power of each base value point of the to-be-predicted day, and adjusts the flywheel operation mode in real time according to the weather condition of the day to output different power levels under different weather conditions, thereby reducing the precision and difficulty of flywheel control and realizing the optimal solution of the flywheel speed.

[0102] The part not described in detail in the application is the technology known to those skilled in the art.

[0103] In the description of the application, it should be understood that the orientation words such as "front, back, upper, lower, left, right", "transverse, vertical, perpendicular, horizontal" and "top, bottom" and the like indicated orientation or position relationship are generally based on the orientation or position relationship shown in the drawings, only for the convenience of describing the application and simplifying the description, without making the opposite statement, these orientation words do not indicate and imply that the device or element referred to must have a particular orientation or be constructed and operated in a particular orientation, therefore, it cannot be understood as a limitation on the scope of protection of the application; the orientation words "inner, outer" refer to the inner and outer of the contour of each component itself.

[0104] For the convenience of description, spatial relative terms such as "over", "above", "upper surface", "upper" and the like can be used herein to describe the spatial position relationship of one device or feature with other devices or features as shown in the drawings. It should be understood that the spatial relative terms are intended to include different orientations in use or operation in addition to the orientation of the device described in the drawings. For example, if the device in the drawing is inverted, the device described as "above" or "over" other devices or structures will be positioned "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below" orientations. The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein are interpreted accordingly.

[0105] In addition, it should be noted that the use of "first", "second" and the like words to define parts, only for the convenience of corresponding parts, such as no further declaration, the above words have no special meaning, therefore, it cannot be understood as a limitation on the scope of protection of the application.

[0106] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A flywheel frequency modulation method based on similar daily photovoltaic power, characterized in that, The method includes: Select several time points throughout the day as base value points; The irradiance of each base point on the day to be predicted is obtained based on the weather forecast, so as to form the irradiance vector of the day to be predicted; Obtain the irradiance vectors of M × N historical days that are M days adjacent to the day to be predicted and M days of the same period in N years. S historical days that best match the weather of the day to be predicted are selected from the irradiance vectors of M×N historical days as a preliminary candidate day set. P historical days with the smallest absolute value of the difference between the irradiance vector of each preliminary candidate day and the irradiance vector of the day to be predicted are selected as a candidate similar day set, where M×N>S>P. The irradiance vector of the day to be predicted and the irradiance gradient vector of each candidate similar day are obtained based on the irradiance vector of the day to be predicted and the irradiance vector of each candidate similar day. Obtain the difference vector between the irradiance gradient vector of the day to be predicted and the irradiance gradient vector of each candidate similar day; Select the candidate similar days corresponding to the K smallest difference vectors as the set of similar days, and obtain the weighting coefficients corresponding to the K similar days, where P > K; The photovoltaic power generation at each base point on the day to be predicted is obtained based on the weighting coefficients corresponding to K similar days and the actual power values ​​of K similar days at each base point; The rotational speed of the flywheel is determined based on the photovoltaic power generation at each baseline point on the day to be predicted, so as to achieve flywheel frequency regulation.

2. The method according to claim 1, characterized in that, Determining the flywheel speed based on the photovoltaic power generation at each baseline point on the day to be predicted, in order to achieve flywheel frequency regulation, includes: The power curve required for frequency regulation on the forecast day is obtained based on the photovoltaic power generation at each base point on the forecast day and reported to the power agency. The power authority generates frequency regulation tasks based on the power curve required for frequency regulation on the predicted date and issues them to the photovoltaic power station; The photovoltaic power plant adjusts the power curve required for frequency regulation based on the real-time operating status of the predicted day, and determines the speed of the flywheel based on the adjusted power curve, thereby controlling the flywheel frequency regulation system to output the corresponding power.

3. The method according to claim 1 or 2, characterized in that, After the photovoltaic power plant adjusts the power curve required for frequency regulation based on the real-time operating status of the predicted day, determines the speed of the flywheel based on the adjusted power curve, and thus controls the flywheel frequency regulation system to output the corresponding power, the method further includes: At a preset time before the photovoltaic power station is shut down, determine whether the flywheel operating speed is greater than the preset speed. If the flywheel operates at a speed higher than the preset speed, the operating speed will be reduced to below the preset speed in order to feed the remaining energy back into the power grid.

4. The method according to claim 1, characterized in that, The weighting coefficients for K similar days are obtained using the following formula: In the formula, θ i Let x0(z) be the weighting coefficient corresponding to the i-th similar day, and let x0(z) be the irradiance of the day to be predicted at the base point t. i (t) represents the irradiance at base point t on the i-th similar day, and K is the number of similar days.

5. The method according to claim 1, characterized in that, The photovoltaic power generation at each baseline point on the day to be predicted is obtained using the following formula: In the formula, P is the photovoltaic power generation at the current base point, and θ i P is the weighting coefficient corresponding to the i-th similar day. i Let K be the photovoltaic power generation on the i-th similar day at the current base value point, and K be the number of similar days.

6. The method according to claims 1 and 2, characterized in that, The speed of the flywheel is determined by the following formula: P=an 2 In the formula, P is the photovoltaic power generation at the current base point, a is the speed coefficient, and n is the speed of the flywheel.

7. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the method of any one of claims 1 to 6.

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