CN114256855B

CN114256855B - Frequency modulation control method and device for wind power plant

Info

Publication number: CN114256855B
Application number: CN202011002768.4A
Authority: CN
Inventors: 左美灵
Original assignee: Jinfeng Technology Co ltd
Current assignee: Beijing Goldwind Science and Creation Windpower Equipment Co Ltd
Priority date: 2020-09-22
Filing date: 2020-09-22
Publication date: 2024-08-06
Anticipated expiration: 2040-09-22
Also published as: ZA202304543B; AU2021349653A1; AU2021349653B2; CN114256855A; WO2022062509A1

Abstract

A frequency modulation control method and device for a wind farm are provided, wherein the frequency modulation control method comprises the following steps: based on the frequency modulation requirement of the wind power plant, aiming at the wind power plant, starting a function of performing frequency modulation processing in a preset frequency modulation control mode; determining a frequency modulation instruction under the preset frequency modulation control mode based on the current frequency of the power grid; determining a coordination control mode of the automatic power generation control system and the preset frequency modulation control mode; and determining a power deviation command value according to the frequency modulation command based on the determined coordination control mode so as to perform frequency modulation processing based on the determined power deviation command value. By adopting the frequency modulation control method and the frequency modulation control device for the wind power plant, which are disclosed by the embodiment of the invention, the wind power plant can be independently controlled according to different frequency modulation modes, so that the accurate control of a power grid is realized.

Description

Frequency modulation control method and device for wind power plant

Technical Field

The present disclosure relates generally to the field of wind power generation technology, and more particularly, to a frequency modulation control method and apparatus for a wind farm.

Background

With the continuous increase of the permeability of the new energy generator set, the safety and stability of the wind generator set in a high-permeability regional power grid are widely concerned. In the actual operation of the power grid, when the electric quantity consumption is not matched with the electric quantity supply, tiny components with smaller change and shorter fluctuation period can be caused to appear in the frequency of the power grid, the frequency disturbance mainly uses the adjusting system of the steam turbine generator unit to directly and automatically adjust the steam turbine valve to complete the power grid load compensation, and the fluctuation of the frequency of the power grid is corrected, so that the process is the primary frequency modulation of the power generator unit.

After the power grid frequency is suddenly changed, when the wind turbine generator is in normal operation and the active output is larger than 20% of rated power Pn, and when the frequency change rate of the grid-connected point exceeds a threshold value (for example, 0.3 Hz/s), the wind turbine generator rapidly responds to the frequency change rate of the system, and the process is inertia response.

At present, the frequency control of the wind turbine participating system mainly comprises two aspects: in the frequency control, the primary frequency modulation and the inertia response are required to be started simultaneously, and the power deviations corresponding to the primary frequency modulation and the inertia response are added to obtain a frequency modulation instruction. In addition, in the current frequency control, the coordination control mode between primary frequency modulation and secondary frequency modulation is single, and independent control on the primary frequency modulation and the secondary frequency modulation cannot be realized.

Disclosure of Invention

It is an object of exemplary embodiments of the present disclosure to provide a method and apparatus for frequency modulation control of a wind farm, which overcomes at least one of the above-mentioned drawbacks.

In one general aspect, there is provided a frequency modulation control method of a wind farm, the frequency modulation control method comprising: based on the frequency modulation requirement of the wind power plant, aiming at the wind power plant, starting a function of performing frequency modulation processing in a preset frequency modulation control mode; determining a frequency modulation instruction under the preset frequency modulation control mode based on the current frequency of the power grid; determining a coordination control mode of an AGC (automatic generation control) system and the preset frequency modulation control mode; and determining a power deviation command value according to the frequency modulation command based on the determined coordination control mode so as to perform frequency modulation processing based on the determined power deviation command value.

Optionally, the frequency modulation control method may further include: and in the process of frequency modulation processing, receiving adjustment of control parameters of a primary frequency modulation mode and/or inertia response frequency modulation mode, and/or indicating a power adjustment direction in the frequency modulation requirement of the wind power plant, wherein a power change function consistent with the power adjustment direction indicated by the frequency modulation requirement of the wind power plant is started under the preset frequency modulation control mode, and the power change function comprises a power increase function and a power decrease function.

Optionally, the coordination control mode may include any one of the following: locking the superposition mode, AGC locking the frequency modulation mode, frequency modulation locking the AGC mode and frequency modulation superposition AGC mode.

Optionally, the coordination control mode may include a lock-up superposition mode, the lock-up superposition mode including a first superposition sub-mode and a second superposition sub-mode, wherein the step of determining the power deviation command value according to the frequency modulation command based on the determined coordination control mode may include: determining a locking superposition mode where the AGC is positioned based on the current frequency of the power grid; determining a power deviation command value based on the frequency modulation command in a superposition mode corresponding to a locked superposition mode where the AGC is located, wherein the superposition mode corresponding to the first superposition sub-mode may be: superposing the AGC power command and the frequency modulation command to obtain a power deviation command value, wherein the superposition mode corresponding to the second superposition sub-mode can be as follows: determining whether the direction of the AGC power command is consistent with the direction of the frequency modulation command, if the direction of the AGC power command is consistent with the direction of the frequency modulation command, superposing the AGC power command and the frequency modulation command to obtain a power deviation command value, and if the direction of the AGC power command is inconsistent with the direction of the frequency modulation command, locking the AGC frequency modulation function and determining the frequency modulation command as the power deviation command value.

Optionally, the step of determining the lockout overlay mode in which the AGC is located based on the current frequency of the power grid may include: and determining whether the current frequency of the power grid is in a blocking dead zone range, if so, determining that the blocking superposition mode in which the AGC is positioned is a first superposition sub-mode, and if not, determining that the blocking superposition mode in which the AGC is positioned is a second superposition sub-mode.

Optionally, the coordination control mode may include an AGC lockout frequency modulation mode, the AGC lockout frequency modulation mode including a first lockout sub-mode and a second lockout sub-mode, wherein, based on the determined coordination control mode, the step of determining the power deviation command value from the frequency modulation command may include: determining whether the AGC is limited in power, if the AGC is limited in power, determining a power deviation instruction value according to the frequency modulation instruction based on a locking mode corresponding to an AGC locking frequency modulation mode in which the AGC is positioned, and if the AGC is not limited in power, obtaining the power deviation instruction value based on the AGC power instruction and the frequency modulation instruction; the locking mode corresponding to the first locking sub-mode may be: and locking the AGC frequency modulation function in the forward direction and the reverse direction, wherein in the first locking sub-mode, locking the AGC frequency modulation function, determining the frequency modulation instruction as a power deviation instruction value, and the locking mode corresponding to the second locking sub-mode can be as follows: and in a second locking sub-mode, if the direction of the AGC power command is consistent with the direction of the frequency modulation command, the AGC power command and the frequency modulation command are overlapped to obtain a power deviation command value, and if the direction of the AGC power command is inconsistent with the direction of the frequency modulation command, the AGC frequency modulation function is locked, and the frequency modulation command is determined to be the power deviation command value.

Optionally, the coordination control mode may include a frequency modulation locked AGC mode, where the frequency modulation locked AGC mode includes a third locked sub-mode and a fourth locked sub-mode, and the power deviation command value is determined according to the frequency modulation command based on a locking mode corresponding to the frequency modulation locked AGC mode in which the AGC is located, where in the third locked sub-mode, the power deviation command value may be determined by: determining whether the frequency modulation command is zero, if the frequency modulation command is zero, determining a power deviation command value to be zero, if the frequency modulation command is not zero, determining whether the AGC is in a frequency modulation exit process, if the AGC is in a frequency modulation exit process, determining a difference value between a current AGC power command and a power command before entering frequency modulation, determining the sum of the frequency modulation command and the difference value to be a power deviation command value, and if the AGC is not in a frequency modulation exit process, determining the frequency modulation command to be a power deviation command value, wherein in a fourth locking sub-mode, the power deviation command value can be determined by the following steps: determining whether the frequency modulation command is zero, if the frequency modulation command is zero, determining a power deviation command value to be zero, if the frequency modulation command is not zero, determining whether a historical AGC power deviation value is zero when the AGC power command is zero, if the historical AGC power deviation value is not zero when the AGC power command is zero, determining whether the direction of the AGC power command is consistent with the direction of the frequency modulation command if the historical AGC power deviation value is zero when the AGC power command is zero, and if the direction of the AGC power command is consistent with the direction of the frequency modulation command, superposing the AGC power command and the frequency modulation command to obtain a power deviation command value, and if the direction of the AGC power command is inconsistent with the direction of the frequency modulation command, determining the frequency modulation command as the power deviation command value.

Optionally, the coordination control mode may include a frequency modulation superposition AGC mode, where the frequency modulation superposition AGC mode includes a third superposition sub-mode and a fourth superposition sub-mode, and the power deviation command value is determined according to the frequency modulation command based on a superposition mode corresponding to the frequency modulation superposition AGC mode where the AGC is located, where in the third superposition sub-mode, the power deviation command value may be determined by: determining whether the frequency modulation instruction is zero; if the frequency modulation instruction is zero, determining that a power deviation instruction value is zero; and if the frequency modulation command is not zero, superposing the AGC power command with the frequency modulation command and the historical AGC power deviation value to obtain a power deviation command value, wherein in a fourth superposition sub-mode, the power deviation command value can be determined by the following steps: determining whether the frequency modulation instruction is zero; if the frequency modulation instruction is zero, determining that a power deviation instruction value is zero; if the frequency modulation command is not zero, determining whether a historical AGC power deviation value is zero when the AGC power command is zero; if the historical AGC power deviation value is not zero when the AGC power command is zero, determining the historical AGC power deviation value as the current AGC power deviation value; if the historical AGC power deviation value is zero when the AGC power command is zero, determining whether the direction of the AGC power command is consistent with the direction of the frequency modulation command; if the direction of the AGC power instruction is consistent with the direction of the frequency modulation instruction, superposing the AGC power instruction with the frequency modulation instruction and the historical AGC power deviation value to obtain a power deviation instruction value; and if the direction of the AGC power command is inconsistent with the direction of the frequency modulation command, superposing the frequency modulation command and the historical AGC power deviation value to obtain a power deviation command value.

In another general aspect, there is provided a frequency modulation control device for a wind farm, the frequency modulation control device comprising: the enabling module is used for starting a function of performing frequency modulation processing in a preset frequency modulation control mode aiming at the wind power plant based on the frequency modulation requirement of the wind power plant; the frequency modulation instruction determining module is used for determining a frequency modulation instruction under the preset frequency modulation control mode based on the current frequency of the power grid; the coordination control module is used for determining a coordination control mode of the AGC and the preset frequency modulation control mode; and the power deviation determining module is used for determining a power deviation command value according to the frequency modulation command based on the determined coordination control mode so as to carry out frequency modulation processing based on the determined power deviation command value.

In another general aspect, there is provided a controller comprising: a processor; and the memory is used for storing a computer program which realizes the frequency modulation control method of the wind power plant when being executed by the processor.

In another general aspect, there is provided a computer readable storage medium storing a computer program which, when executed by a processor, implements a method of frequency modulation control of a wind farm as described above.

By adopting the frequency modulation control method and the frequency modulation control device for the wind power plant, which are disclosed by the embodiment of the invention, the wind power plant can be independently controlled according to different frequency modulation modes, so that the accurate control of a power grid is realized.

Drawings

The foregoing and other objects, features and advantages of exemplary embodiments of the present disclosure will become more apparent from the following detailed description, taken in conjunction with the accompanying drawings that illustrate exemplary embodiments.

FIG. 1 illustrates a flowchart of a method of frequency modulation control of a wind farm according to an exemplary embodiment of the present disclosure;

FIG. 2 illustrates a schematic diagram of a primary frequency droop control according to an exemplary embodiment of the present disclosure;

FIG. 3 illustrates a primary frequency modulation step response index graph according to an exemplary embodiment of the present disclosure;

FIG. 4 illustrates a flowchart of steps for determining a power offset command value in a lockout stack mode, according to an exemplary embodiment of the present disclosure;

Fig. 5 is a flowchart illustrating steps of determining a power offset command value in an AGC lockout frequency modulation mode according to an exemplary embodiment of the present disclosure;

fig. 6 illustrates a flowchart of steps for determining a power offset command value in a frequency modulated locked AGC mode according to an exemplary embodiment of the present disclosure;

fig. 7 is a flowchart illustrating steps of determining a power deviation command value in a frequency modulated superimposed AGC mode according to an exemplary embodiment of the present disclosure;

FIG. 8 illustrates a block diagram of a frequency modulation control device of a wind farm according to an exemplary embodiment of the present disclosure;

Fig. 9 shows a block diagram of a controller according to an exemplary embodiment of the present disclosure.

Detailed Description

Various example embodiments will now be described more fully with reference to the accompanying drawings, in which some example embodiments are shown.

Fig. 1 shows a flowchart of a method of frequency modulation control of a wind farm according to an exemplary embodiment of the present disclosure.

Referring to fig. 1, in step S10, a function of performing a frequency modulation process in a predetermined frequency modulation control manner is turned on for a wind farm based on a frequency modulation requirement of the wind farm.

For example, the predetermined frequency modulation control scheme may refer to a frequency modulation control scheme indicated in a frequency modulation demand of a wind farm. As an example, the predetermined frequency modulation control scheme may include at least one of: primary frequency modulation mode, inertia response frequency modulation mode.

Here, primary frequency modulation (frequency variation frequency modulation) refers to an automatic control process in which, when the frequency of a power grid deviates from a rated value, a control system of each wind turbine in the power grid automatically controls the increase or decrease of active power of the wind turbine, that is, the frequency deviation is reduced by adjusting active power, so that the frequency of the power grid is maintained stable. That is, the primary frequency modulation function is one of dynamic means for ensuring the active power balance of the power grid, and when the frequency of the power grid is increased (higher than the rated value), the primary frequency modulation function controls the wind turbine generator to reduce the grid-connected active power, and when the frequency of the power grid is reduced (lower than the rated value), the primary frequency modulation function controls the wind turbine generator to increase the grid-connected active power.

The inertia response frequency modulation mode (frequency change rate frequency modulation) can refer to the characteristic that the active output of the wind turbine generator changes along with time after the frequency of the power grid is suddenly changed. And when the wind turbine is in normal operation and the active power output is larger than 20% of rated power Pn, and the frequency change rate of the grid connection point exceeds a threshold (for example, 0.3 Hz/s), the wind turbine is rapidly responsive to the frequency change rate of the system.

For example, by controlling the rotor speed change of the wind turbine and utilizing the rotor kinetic energy to obtain the extra generator power of the wind turbine, an inertia response control loop related to the system frequency is added in the speed change control link of the wind turbine, and the original speed control link can be corrected, so that the wind turbine can adjust the active output of the wind turbine in a shorter reaction time, namely, has an effective response to the system frequency.

When the frequency of the power grid is kept at the rated value and is unchanged, the inertia response control link does not play any role, and when the frequency of the power grid is changed, the inertia response control link starts to act according to the control requirement. When the frequency of the power grid is reduced, the wind turbine generator reduces the rotating speed of the rotor through an inertia response control link, so that part of the kinetic energy of the rotor is converted into active power and input into the system. On the contrary, when the frequency of the power grid is increased, the wind turbine absorbs part of electromagnetic power by increasing the rotating speed of the rotor, and the active power obtained by conversion is stored in the rotor of the wind turbine, so that the output of the active power is reduced, namely, inertia response control of the wind turbine participating in system frequency modulation is realized.

At present, a wind turbine generator system generally has inertia response and primary frequency modulation control capability, wherein a frequency modulation processing mode is that a primary frequency modulation mode and an inertia response frequency modulation mode are simultaneously started, and power deviations corresponding to the primary frequency modulation mode and the inertia response mode are overlapped to obtain a frequency modulation instruction. However, in the exemplary embodiments of the present disclosure, not only the primary frequency modulation mode and the inertia response frequency modulation mode may be turned on at the same time, but also only the primary frequency modulation mode may be turned on, or only the inertia response frequency modulation mode may be turned on, that is, the primary frequency modulation mode and the inertia response frequency modulation mode may be independently controlled, so as to achieve accurate control of the power grid.

In an example, in addition to indicating the frequency modulation control manner, the frequency modulation requirement of the wind farm may also indicate the power adjustment direction, i.e. whether the power adjustment increases or decreases the power.

In this case, after the function of performing the frequency modulation process in the predetermined frequency modulation control manner is turned on for the wind farm, the power change function consistent with the power adjustment direction indicated by the frequency modulation demand of the wind farm is also turned on in the predetermined frequency modulation control manner. As an example, the power change function may include a power increase function and a power decrease function.

In an alternative example, the frequency modulation control method of the wind farm according to the exemplary embodiment of the present disclosure may further include: and in the process of the frequency modulation processing, receiving adjustment of control parameters of the primary frequency modulation mode and/or the inertia response frequency modulation mode.

In order to realize accurate control, independent investment and independent parameter configuration are carried out on a primary frequency modulation mode and an inertia response frequency modulation mode, and control parameters can be directly controlled by a dispatching system of a wind power plant. The control parameters for the primary frequency modulation mode and the inertia response frequency modulation mode are shown in table 1 below.

TABLE 1

Through the real-time adjustment of the control parameters, unified, automatic and accurate control can be realized, the defect of inflexibility in the prior art is overcome, the flexible and controllable target of the power grid is met, and the friendly power grid is realized.

In step S20, a tuning instruction in a predetermined tuning control mode is determined based on the current frequency of the power grid.

Here, the tuning instruction includes a power deviation value in a predetermined tuning control manner. For example, for the case where the primary mode is only turned on (i.e., the predetermined frequency modulation control mode is the primary mode), the frequency modulation command may refer to the power deviation value determined in the primary mode.

For the case where only the inertia-responsive frequency modulation mode is on (i.e., the case where the predetermined frequency modulation control mode is the inertia-responsive frequency modulation mode), the frequency modulation command may refer to the power deviation value determined in the inertia-responsive frequency modulation mode.

For the case where the primary frequency modulation mode and the inertia response frequency modulation mode are turned on simultaneously (i.e., the case where the predetermined frequency modulation control mode is the primary frequency modulation mode and the inertia response frequency modulation mode), the frequency modulation instruction may refer to superposition of the power deviation value determined in the primary frequency modulation mode and the power deviation value determined in the inertia response frequency modulation mode.

The process of determining the power offset value in the primary frequency modulation mode is described below with reference to fig. 2.

Fig. 2 illustrates a schematic diagram of a primary frequency droop control according to an exemplary embodiment of the present disclosure.

As shown in fig. 2, in the field station of the new energy source (such as a wind farm and a photovoltaic power station), for the case that the frequency of the power grid is higher than the rated value (i.e., high-frequency disturbance), the action amount corresponding to the primary frequency modulation mode is not adjusted downward if the rated output reaches 10%, and for the case that the frequency of the power grid is lower than the rated value (i.e., low-frequency disturbance), the action amount corresponding to the primary frequency modulation mode is not adjusted upward if the rated output reaches 5%.

For example, the primary frequency modulation droop characteristic may be implemented by setting a frequency and active power fold line function, that is, the frequency variation amount modulation means that the primary frequency modulation active adjustment amount and the frequency deviation of the new energy station conform to the droop characteristic outside the primary frequency modulation dead zone, and as an example, the primary frequency modulation active adjustment amount and the frequency deviation are expressed by the following formula:

In the formula (1), P represents a current active power value, P ₀ represents an active power initial value, P _N represents a rated power value, f represents a current grid-connected point frequency value, f _d represents a primary frequency modulation dead zone, f _N represents a rated value of frequency, and delta% represents a difference adjustment coefficient of primary frequency modulation of a new energy station. Here, the difference between P and P ₀ is the power offset in primary frequency modulation mode.

As an example, the slip coefficient δ% is a ratio of a system frequency variation nominal value (reference value for rated frequency) to an active power variation nominal value (reference value for rated power).

For example, in the droop characteristic shown in fig. 2, the primary frequency modulation dead zone f _d is set to 0.05Hz, the difference adjustment coefficient δ% is set to 5%, the primary frequency modulation power up-regulation maximum power limiter is set to 6%P _N, and the primary frequency modulation power down-regulation maximum power limiter is set to 10% p _N.

Fig. 3 illustrates a primary frequency modulation step response index graph according to an exemplary embodiment of the present disclosure.

As shown in fig. 3, the primary fm step response index is as follows: t ₀ denotes a start time, t _d denotes a start time, t _up denotes a response time, t _s denotes a regulation time, P _N denotes a rated power value, and Δp denotes a target power regulation amount.

It should be appreciated that the above-described manner of determining the power offset value in the primary frequency modulation mode is merely an example, and those skilled in the art may determine the power offset value in the primary frequency modulation mode in other manners. Further, the parameter values listed in fig. 2 and 3 are merely examples, and the present disclosure is not limited thereto, and one skilled in the art may adjust each parameter value as needed.

The process of determining the power offset value in the inertia-responsive frequency modulation mode is described below.

In the inertia response frequency modulation mode, the active power variation Δp (i.e., the power deviation value) of the virtual synchronous generator should satisfy the following formula:

In the formula (2), f represents a current grid-connected point frequency value, f _N represents a rated value of frequency, P _N represents a rated power value, and T _J represents an inertia time constant.

For example, the inertia time constant T _J may be calculated using the following formula:

in the formula (3), J represents the rotational inertia of the virtual synchronous generator, P _N represents the rated active power value of the virtual synchronous generator, and ω _N represents the rated angular speed of the system.

It should be appreciated that the above-described manner of determining the power offset value in the inertia-responsive frequency modulation manner is merely an example, and those skilled in the art may determine the power offset value in the inertia-responsive frequency modulation manner in other manners.

Returning to fig. 1, in step S30, a coordinated control mode of the automatic power generation control system AGC and a predetermined frequency modulation control scheme is determined.

The above-mentioned preset frequency modulation control mode is a differential regulation, which can only mitigate the change degree of the power grid frequency, so that it is also necessary to utilize a synchronizer to increase and decrease the load of some wind turbines so as to restore the power grid frequency, and this process is called secondary frequency modulation.

That is, after the secondary frequency modulation, the power grid frequency can be accurately kept at a constant value, and at present, there are two modes of secondary frequency modulation: the dispatching system issues a total instruction to each new energy station to adjust the load; the wind turbine adopts an AGC mode to realize automatic load scheduling of the wind turbine. The primary frequency modulation is to automatically adjust the load of the wind turbine generator according to the change of the power grid frequency by the turbine speed regulating system so as to recover the power grid frequency, and the secondary frequency modulation is to manually adjust the load of the wind turbine generator according to the power grid frequency.

In the exemplary embodiment of the present disclosure, four coordination control modes are listed to complete coordination control of the predetermined fm control mode and the AGC. Here, if the cooperative control mode is not selected, the frequency modulation process is performed only in a predetermined frequency modulation control manner at this time, and in this case, the power deviation command value is a frequency modulation command.

As an example, the coordinated control mode may include, but is not limited to, any of the following: locking the superposition mode, AGC locking the frequency modulation mode, frequency modulation locking the AGC mode and frequency modulation superposition AGC mode.

In the exemplary embodiment of the disclosure, a plurality of coordination control modes are arranged between the preset frequency modulation control mode and the AGC, each coordination control mode further comprises each sub-mode, and the plurality of coordination control modes coexist and complementarily interfere so as to realize flexible selection. The predetermined frequency modulation control scheme and the AGC coordination control scheme are shown in table 2 below.

TABLE 2

As shown in table 2, for the lock-up superposition mode, the input and the output of the coordination control mode can be controlled online in real time. The input and the exit of each coordination control mode can be controlled in real time based on a dispatching system aiming at the AGC locking frequency modulation mode, the frequency modulation locking AGC mode and the frequency modulation superposition AGC mode. For example, the three coordination control modes may be provided to the scheduling system, the scheduling system may select one coordination control mode from the provided coordination control modes, and feed back the mode selection information, and the selected coordination control mode may be indicated in the fed back mode selection information.

In step S40, a power deviation command value is determined based on the determined coordination control mode according to the frequency modulation command, and frequency modulation processing is performed based on the determined power deviation command value.

For example, the determined power deviation command value may be issued to each wind turbine in the wind farm to control each wind turbine to perform frequency modulation.

In the exemplary embodiment of the disclosure, the coordination control mode between the predetermined frequency modulation control mode (such as primary frequency modulation) and secondary frequency modulation can be controlled independently, so as to realize accurate control of the power grid. The process of determining the power deviation command value in the different coordination control modes is described below with reference to fig. 4 to 7.

Fig. 4 shows a flowchart of steps for determining a power deviation command value in a lockout stack mode, according to an exemplary embodiment of the present disclosure.

Referring to fig. 4, in step S411, a lock-up superposition mode in which the AGC is located is determined based on the current frequency of the power grid.

As an example, the lockout overlay mode may include a first overlay sub-mode and a second overlay sub-mode, at which time it may be determined which overlay sub-mode the AGC is in based on the current frequency of the power grid.

For example, it may be determined whether the current frequency of the power grid is within the lock-out dead zone range, if it is within the lock-out dead zone range (e.g., less than or equal to an upper value of the lock-out dead zone range, greater than or equal to a lower value of the lock-out dead zone range), then the lock-out superposition mode in which the AGC is located is determined to be the first superposition sub-mode, and if it is not within the lock-out dead zone range (e.g., greater than an upper value of the lock-out dead zone range or less than a lower value of the lock-out dead zone range), then the lock-out superposition mode in which the AGC is located is determined to be the second superposition sub-mode.

In step S412, a power deviation command value is determined based on the frequency modulation command in a superimposed manner corresponding to the lock superimposed mode in which the AGC is located.

For example, the superimposition manner corresponding to the first superimposition sub-mode may be: the AGC power command is superimposed with the frequency modulation command to obtain a power deviation command value, i.e., algebraically sum the AGC power command and the frequency modulation command if within the lock dead zone range.

Here, the AGC power command refers to a power offset value determined under AGC, and the power offset value under AGC may be determined in various ways.

For example, the superimposition manner corresponding to the second superimposition sub-mode may be: outside the dead zone range of locking, the positive superposition and the reverse locking are performed. Specifically, it may be determined whether the direction of the AGC power command coincides with the direction of the tuning command, if the direction of the AGC power command coincides with the direction of the tuning command (forward direction), the AGC power command is superimposed with the tuning command to obtain a power deviation command value, and if the direction of the AGC power command does not coincide with the direction of the tuning command (reverse direction), the AGC tuning function is blocked, at which point the power deviation command value is the tuning command.

Fig. 5 shows a flowchart of steps for determining a power offset command value in AGC lockout frequency modulation mode, according to an exemplary embodiment of the present disclosure.

Referring to fig. 5, in step S421, it is determined whether AGC is power limited.

In one example, whether the AGC is power limited may be determined by: and determining a power reference value, determining whether the power reference value meets a preset condition, if the power reference value meets the preset condition, determining that the AGC is not limited in power, and if the power reference value does not meet the preset condition, determining that the AGC is limited in power.

As an example, the power reference value may include, but is not limited to, any of the following: measured power deviation value, rated power deviation value and power value under AGC.

For the case where the power reference value is the measured power offset value, the measured power offset value may be determined based on the power value under AGC and the measured power value.

For example, the following formula may be utilized to determine:

DeltP_real＝P_{cmd_agc}-P_real (4)

In the formula (4), deltP _real denotes a measured power deviation value, P _{cmd_agc} denotes a power value under AGC, and P _real denotes a measured power value.

In this case, if the measured power deviation value DeltP _real is smaller than the first set value α, it is determined that the power reference value satisfies the preset condition, and if the measured power deviation value DeltP _real is not smaller (i.e., is greater than or equal to) the first set value α, it is determined that the power reference value does not satisfy the preset condition.

In an example, the first set value α may be determined based on the rated power value P _rated, for example, α=0.1×p _rated.

For the case where the power reference value is the rated power deviation value, the rated power deviation value may be determined based on the power value under AGC and the rated power value.

For example, the following formula may be utilized to determine:

DeltP_rared＝P_{cmd_agc}-P_rated (5)

In the formula (5), deltP _rated denotes a rated power deviation value, P _{cmd_agc} denotes a power value under AGC, and P _rated denotes a rated power value.

In this case, if the rated power deviation value DeltP _rated is smaller than the second set value β, it is determined that the power reference value satisfies the preset condition, and if the rated power deviation value DeltP _rated is not smaller (i.e., is greater than or equal to) the second set value β, it is determined that the power reference value does not satisfy the preset condition.

In an example, the second set value β may be determined based on the rated power value P _rated, for example, β=0.01×p _rated. Here, the first set value α is greater than the second set value β.

For the case where the power reference value is the power value under AGC P _{cmd_agc}, if P _{cmd_agc} is equal to the third set value, it is determined that the power reference value satisfies the preset condition, and if P _{cmd_agc} is not equal to the third set value, it is determined that the power reference value does not satisfy the preset condition. As an example, the third setting may be equal to zero.

Here, it should be understood that the values of the first set value α, the second set value β, and the third set value listed above are only examples, and the present disclosure is not limited thereto, and those skilled in the art may adjust the values of the respective set values as needed.

That is, when the AGC is limited in power, the AGC blocks the frequency modulation function, after the AGC is recovered in power limitation, the frequency modulation can be automatically adjusted according to the actual requirement, the frequency modulation is adjusted based on the current power, if the AGC is limited in power during the frequency modulation action, the frequency modulation is immediately withdrawn, and the frequency modulation action signal is recovered.

If the AGC is not power limited, step S422 is performed: a power offset command value is obtained based on the AGC power command and the frequency modulation command. For example, the power offset command value may be obtained by superimposing an AGC power command with a frequency modulation command.

At the moment, the AGC does not lock the frequency modulation function, and when the frequency of the grid-connected point exceeds the dead zone, the frequency modulation action is triggered, and the AGC and the dispatching frequency modulation action signals are sent.

For example, the AGC lock-out frequency modulation mode may include, but is not limited to, a first lock-out sub-mode, which may refer to both forward and reverse lock-out of the AGC frequency modulation function, and a second lock-out sub-mode, which may refer to reverse lock-out of the AGC frequency modulation function, i.e., lock-out the AGC frequency modulation function when the AGC is power limited and the direction of the AGC power command is opposite to the direction of the frequency modulation command, and not lock-out when the directions are the same, as an example.

If the AGC is power limited, a power offset command value may be determined from the frequency modulation command based on a lock-out pattern corresponding to the AGC lock-out frequency modulation mode in which the AGC is located.

For example, in step S423, it is determined whether the AGC frequency tuning function reverse lock is on, i.e., whether the second lock sub-mode is on. Here, which lockout sub-mode is turned on may be controlled by the scheduling system.

If the AGC fm function reverse blocking is not on, then step S424 is performed: it is determined that the AGC is in the first lockout sub-mode.

In step S425, in the first lock sub-mode, the AGC frequency modulation function is locked and the frequency modulation command is determined as a power deviation command value.

If the AGC fm function reverse latch is on, then step S426 is performed: the AGC is determined to be in a second lockout sub-mode.

In step S427, it is determined whether the fm instruction DeltP _pfc is zero.

If the FM instruction DeltP _PFC is zero, then step S428 is performed: the power offset command value is determined to be zero. In this case, agc_ AGCCommandP0 assignment, AGCDeltPFlagOld assignment may also be performed. Here, agc_ AGCCommandP0 represents a power value of a start point (when AGC is entered), and AGCDeltPFlagOld represents a historical AGC power deviation value, that is, an AGC power deviation value when frequency modulation control was last performed.

If the FM instruction DeltP _PFC is not zero, then step S429 is performed: it is determined whether the judgment condition is satisfied.

As an example, determining whether the judgment condition is satisfied may refer to determining whether AGCDeltPFlagOld is equal to zero when pcmagc AGC AGCCommandP0 is equal to zero.

If pcmd_agc-agc_ AGCCommandP0 is equal to zero, AGCDeltPFlagOld is not equal to zero, it is determined that the judgment condition is satisfied, and if pcmd_agc-agc_ AGCCommandP0 is equal to zero, AGCDeltPFlagOld is equal to zero, it is determined that the judgment condition is not satisfied.

If the judgment condition is satisfied, step S430 is performed: the historical AGC power bias value is determined as the current AGC power bias value, i.e., AGCDELTPFLAG = AGCDeltPFlagOld. At this time, the frequency modulation command is superimposed with AGCDELTPFLAG to obtain a power deviation command value.

If the judgment condition is not satisfied, step S431 is performed: it is determined whether the direction of the AGC power command is consistent with the direction of the frequency modulation command.

For example, the direction of the PCmd_agc-AGC_ AGCCommandP and the direction of DeltP _PFC can be determined.

If the direction of the AGC power command does not coincide with the direction of the frequency modulation command, step S432 is performed: the AGC frequency modulation function is blocked and the frequency modulation command is determined to be a power deviation command value.

If the direction of the AGC power command coincides with the direction of the frequency modulation command, step S433 is performed: the power command and the frequency modulation command are superimposed to obtain a power deviation command value.

Fig. 6 illustrates a flowchart of steps for determining a power offset command value in a frequency modulated locked AGC mode according to an exemplary embodiment of the present disclosure.

As an example, the frequency modulated dwell AGC mode may include, but is not limited to, a third dwell sub-mode and a fourth dwell sub-mode, e.g., the third dwell sub-mode may refer to forward and reverse dwell and the fourth dwell sub-mode may refer to reverse dwell.

In this case, the power deviation command value may be determined from the frequency modulation command based on a lock-out manner corresponding to a frequency modulation lock-out AGC mode in which the AGC is located.

Specifically, referring to fig. 6, in step S441, it is determined whether the reverse latch is opened.

If the reverse lock is not on, it indicates that the AGC is in the third lock sub-mode, i.e., the forward and reverse lock. In step S442, it is determined whether the frequency modulation instruction is zero.

If the frequency modulation instruction is zero, step S443 is executed: the power deviation command value is determined to be zero BlockLogicDeltP =0.

If the frequency modulation instruction is not zero, step S444 is performed: it is determined whether the AGC is in the process of fm down. Here, various ways may be utilized to determine whether the AGC is in the process of fm exit.

If the AGC is not in the process of fm exit, then step S445 is performed: the frequency modulation command is determined as a power deviation command value.

If the AGC is in the process of fm exit, then step S446 is performed: and determining a difference value between the current AGC power command and the power command before frequency modulation, and determining the sum of the frequency modulation command and the difference value as a power deviation command value.

For example, the AGC power command may be determined using the following equation:

DeltP_AGC＝Pcmd_agc-PFC_AGCCommandP0 (6)

In the formula (6), deltP _agc represents a power deviation value under AGC, pcmd_agc represents a power value under AGC, and pfc_ AGCCommandP0 represents a power value of a start point.

If the reverse latch is on, indicating that the AGC is in the fourth latch sub-mode, in step S447, it is determined whether the fm command is zero.

If the frequency modulation instruction is zero, step S448 is performed: the power deviation command value BlockLogicDeltP is determined to be zero, and AGCDeltPFlagOld =0.

If the frequency modulation instruction is not zero, step S449 is performed: it is determined if AGCDeltPFlagOld is zero when AGC power command DeltP _agc is zero.

If AGCDeltPFlagOld is not zero when the AGC power command is zero, then step S450 is performed: and determining the historical AGC power deviation value as the current AGC power deviation value, and at the moment, superposing the frequency modulation command and AGCDELTPFLAG to obtain a power deviation command value.

If AGCDeltPFlagOld is zero when the AGC power command is zero, step S451 is performed: it is determined whether the direction of AGC power command DeltP _agc is consistent with the direction of fm command DeltP _fpc.

If the direction of the AGC power command is not consistent with the direction of the frequency modulation command, step S452 is performed: the frequency modulation command is determined as a power deviation command value BlockLogicDeltP.

If the direction of the AGC power command coincides with the direction of the frequency modulation command, step S453 is performed: the AGC power command is superimposed with the frequency modulation command to obtain a power offset command value.

Fig. 7 shows a flowchart of steps for determining a power deviation command value in a frequency modulated superimposed AGC mode according to an exemplary embodiment of the present disclosure.

As an example, the frequency modulated superimposed AGC mode may include, but is not limited to, a third superimposed sub-mode and a fourth superimposed sub-mode, e.g., the third superimposed sub-mode may refer to a forward and reverse superimposed, and the fourth superimposed sub-mode may refer to a forward superimposed.

In this case, the power deviation command value may be determined from the frequency modulation command further based on a superimposition manner corresponding to the frequency modulation superimposition AGC mode in which the AGC is located.

Referring to fig. 7, in step S461, it is determined whether forward superimposition is on.

If the forward superposition is not on, it indicates that the AGC is in the third superposition sub-mode, i.e., both the forward and reverse AGC superimposes the frequency modulation command, and in step S462, it is determined whether the frequency modulation command is zero.

If the frequency modulation instruction is zero, step S463 is executed: the power deviation command value is determined to be zero, i.e., blockLogicDeltP =0.

If the frequency modulation instruction is not zero, then step S464 is performed: the AGC power command is superimposed with the frequency modulation command, pa_ Delt _ AGCOld to obtain a power offset command value.

For example, the power deviation command value may be determined using the following formula:

BlockLogicDeltP＝DeltP_FPC+DeltP_AGC+PA_Delt_AGCOld (7)

in the formula (7), blockLogicDeltP denotes a power deviation command value, deltP _fpc denotes a power deviation value under a predetermined frequency modulation control mode, deltP _agc denotes a power deviation value under AGC, and pa_ Delt _ AGCOld denotes a history AGC power deviation value.

If the forward superposition is on, indicating that the AGC is in the fourth superposition sub mode, in step S465, it is determined whether the frequency modulation command is zero.

If the frequency modulation instruction is zero, step S466 is executed: the power deviation command value is determined to be zero, i.e., blockLogicDeltP =0.

If the frequency modulation instruction is not zero, step S467 is performed: it is determined whether the historical AGC power offset value is zero when the AGC power command is zero.

If the historical AGC power offset value is not zero when the AGC power command is zero, then step S468 is performed: and determining the historical AGC power deviation value as the current AGC power deviation value, and at the moment, superposing the frequency modulation command and AGCDELTPFLAG to obtain a power deviation command value.

If the historical AGC power deviation value is zero when the AGC power command is zero, step S469 is performed: it is determined whether the direction of AGC power command DeltP _agc is consistent with the direction of fm command DeltP _fpc.

If the direction of the AGC power command does not coincide with the direction of the frequency modulation command, step S470 is performed: and superposing the frequency modulation instruction and the historical AGC power deviation value PA_ Delt _ AGCOld to obtain a power deviation instruction value.

BlockLogicDeltP＝DeltP_FPC+PA_Delt_AGCOld (8)

in the formula (8), blockLogicDeltP denotes a power deviation command value, deltP _fpc denotes a power deviation value in a predetermined frequency modulation control mode, and pa_ Delt _ AGCOld denotes a historical AGC power deviation value.

If the direction of the AGC power command coincides with the direction of the frequency modulation command, step S471 is performed: and superposing the AGC power command with the frequency modulation command and the historical AGC power deviation value PA_ Delt _ AGCOld to obtain a power deviation command value, as shown in the formula (7).

Fig. 8 shows a block diagram of a frequency modulation control device of a wind farm according to an exemplary embodiment of the present disclosure.

As shown in fig. 8, a frequency modulation control apparatus 100 of a wind farm according to an exemplary embodiment of the present disclosure includes: an enabling module 101, a tuning instruction determining module 102, a coordination control module 103 and a power deviation determining module 104. In one example, the frequency modulation control device 100 may be provided in a wind farm controller.

Specifically, the enabling module 101 turns on a function of performing frequency modulation processing in a predetermined frequency modulation control manner for the wind farm based on a frequency modulation requirement of the wind farm.

In addition to this, the frequency modulation requirement of the wind farm may also indicate the direction of the power adjustment, i.e. whether the power adjustment increases or decreases the power.

In this case, after the function of performing the frequency modulation process in the predetermined frequency modulation control manner is turned on for the wind farm, the enabling module 101 also turns on the power variation function consistent with the power adjustment direction indicated by the frequency modulation demand of the wind farm in the predetermined frequency modulation control manner. As an example, the power change function may include a power increase function and a power decrease function.

In an alternative example, the enabling module 101 receives adjustments to control parameters of the primary frequency modulation mode and/or the inertia-responsive frequency modulation mode during the frequency modulation process.

The tuning instruction determination module 102 determines a tuning instruction in a predetermined tuning control mode based on the current frequency of the power grid.

For example, for the case where the primary mode is only turned on (i.e., the predetermined frequency modulation control mode is the primary mode), the frequency modulation command may refer to the power deviation value determined in the primary mode.

The coordination control module 103 determines a coordination control mode of the automatic power generation control system AGC and a predetermined frequency modulation control mode.

The power deviation determination module 104 determines a power deviation command value according to the frequency modulation command based on the determined coordination control mode, and then performs frequency modulation processing based on the determined power deviation command value.

For the case where the coordination control mode is the lock superposition mode, the process of determining the power deviation command value by the power deviation determining module 104 is: and determining a locked superposition mode where the AGC is positioned based on the current frequency of the power grid, and determining a power deviation command value based on the frequency modulation command in a superposition mode corresponding to the locked superposition mode where the AGC is positioned.

For the case where the coordination control mode is the AGC lockout frequency modulation mode, the process of determining the power offset command value by the power offset determination module 104 is: determining whether the AGC is limited in power, if the AGC is not limited in power, obtaining a power deviation command value based on the AGC power command and the frequency modulation command, and if the AGC is limited in power, determining the power deviation command value according to the frequency modulation command based on a locking mode corresponding to an AGC locking frequency modulation mode in which the AGC is located.

For the case where the coordination control mode is the fm lock AGC mode, the process of determining the power offset command value by the power offset determination module 104 is: the power offset command value may be determined from the frequency modulation command based on a lock-out scheme corresponding to a frequency modulation lock-out AGC mode in which the AGC is located.

For the case where the coordination control mode is the fm superimposed AGC mode, the process of determining the power offset command value by the power offset determination module 104 is: the power offset command value may be determined from the frequency modulation command based on a superposition scheme corresponding to a frequency modulation superposition AGC where the AGC is located.

Since the manner in which the power deviation command value is determined in the different coordination control modes has been described in detail in the above-described fig. 4 to 7, the contents of this portion will not be repeated in this disclosure.

As shown in fig. 9, the controller 200 according to an exemplary embodiment of the present disclosure includes: a processor 201 and a memory 202.

In particular, the memory 202 is used to store a computer program which, when executed by the processor 201, implements the frequency modulation control method of a wind farm described above.

Here, the frequency modulation control method of the wind farm shown in fig. 1 may be executed in the processor 201 shown in fig. 9. That is, each module shown in fig. 8 may be implemented by a general-purpose hardware processor such as a digital signal processor, a field programmable gate array, or the like, or may be implemented by a special-purpose hardware processor such as a special-purpose chip, or may be implemented in a software manner entirely by a computer program, for example, may be implemented as each module in the processor 201 shown in fig. 9. As an example, the controller 200 shown in fig. 9 may be a wind farm controller.

There is also provided, in accordance with an exemplary embodiment of the present disclosure, a computer-readable storage medium storing a computer program. The computer readable storage medium stores a computer program which, when executed by a processor, causes the processor to perform the above-described frequency modulation control method of a wind farm. The computer readable recording medium is any data storage device that can store data which can be read out by a computer system. Examples of the computer-readable recording medium include: read-only memory, random access memory, compact disc read-only, magnetic tape, floppy disk, optical data storage device, and carrier waves (such as data transmission through the internet via wired or wireless transmission paths).

The frequency modulation control method and the frequency modulation control device for the wind power plant can realize independent input control of a primary frequency modulation mode and an inertia response frequency modulation mode, realize accurate control of a power grid, and also realize independent control of a coordination control mode between the primary frequency modulation and the secondary frequency modulation so as to further realize accurate control of the power grid.

In addition, according to the frequency modulation control method and device of the wind power plant, which are disclosed by the embodiment of the invention, more power grid requirements and more regional environments can be met.

While the present disclosure has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present disclosure as defined by the following claims.

Claims

1. The frequency modulation control method for the wind farm is characterized by comprising the following steps of:

Based on the frequency modulation requirement of the wind power plant, aiming at the wind power plant, starting a function of performing frequency modulation processing in a preset frequency modulation control mode;

determining a frequency modulation instruction under the preset frequency modulation control mode based on the current frequency of the power grid;

determining a coordination control mode of an AGC (automatic generation control) system and the preset frequency modulation control mode;

determining a power deviation command value according to the frequency modulation command based on the determined coordination control mode, so as to perform frequency modulation processing based on the determined power deviation command value;

wherein the coordination control mode comprises a locking superposition mode, the locking superposition mode comprises a first superposition sub-mode and a second superposition sub-mode,

Wherein the step of determining a power deviation command value from the frequency modulation command based on the determined coordination control mode comprises:

Based on the current frequency of the power grid, determining a locking superposition mode in which the AGC is positioned,

Determining a power deviation command value based on the frequency modulation command in a superimposed manner corresponding to a lock superimposed mode in which the AGC is located,

The superposition mode corresponding to the first superposition sub-mode is as follows: superposing the AGC power command and the frequency modulation command to obtain a power deviation command value,

The superposition mode corresponding to the second superposition sub-mode is as follows: determining whether the direction of the AGC power command is consistent with the direction of the frequency modulation command, if the direction of the AGC power command is consistent with the direction of the frequency modulation command, superposing the AGC power command and the frequency modulation command to obtain a power deviation command value, and if the direction of the AGC power command is inconsistent with the direction of the frequency modulation command, locking the AGC frequency modulation function and determining the frequency modulation command as the power deviation command value.

2. The method of claim 1, wherein the predetermined frequency modulation control scheme is a frequency modulation control scheme indicated in a frequency modulation demand of a wind farm,

And/or, the predetermined frequency modulation control mode comprises at least one of the following: primary frequency modulation mode, inertia response frequency modulation mode.

3. The frequency modulation control method according to claim 2, characterized in that the frequency modulation control method further comprises: during the frequency modulation process, the adjustment of control parameters of the primary frequency modulation mode and/or the inertia response frequency modulation mode is received,

And/or the frequency modulation requirement of the wind power plant also indicates the power adjustment direction, wherein a power change function consistent with the power adjustment direction indicated by the frequency modulation requirement of the wind power plant is started under the preset frequency modulation control mode, and the power change function comprises a power increase function and a power decrease function.

4. The method of frequency modulation control according to claim 1, wherein the step of determining the lock-up superposition mode in which the AGC is located based on the current frequency of the power grid comprises:

It is determined whether the current frequency of the power grid is within the lock-out dead zone range,

If the AGC is within the lock dead zone range, determining that the lock superposition mode in which the AGC is located is a first superposition sub-mode,

And if the AGC is not in the blocking dead zone range, determining that the blocking superposition mode in which the AGC is positioned is a second superposition sub-mode.

5. The method of claim 1, wherein the coordinated control mode further comprises an AGC lockout frequency mode, the AGC lockout frequency mode comprising a first lockout sub-mode and a second lockout sub-mode,

It is determined whether the AGC is power limited,

If the AGC is limited in power, a power deviation command value is determined according to the frequency modulation command based on a locking mode corresponding to an AGC locking frequency modulation mode in which the AGC is positioned,

If the AGC is not limited in power, a power deviation command value is obtained based on the AGC power command and the frequency modulation command;

The locking mode corresponding to the first locking sub-mode is as follows: the AGC FM function is locked in both forward and reverse directions, wherein in a first locking sub-mode, the AGC FM function is locked and the FM instruction is determined as a power deviation instruction value,

The locking mode corresponding to the second locking sub-mode is as follows: and in a second locking sub-mode, if the direction of the AGC power command is consistent with the direction of the frequency modulation command, the AGC power command and the frequency modulation command are overlapped to obtain a power deviation command value, and if the direction of the AGC power command is inconsistent with the direction of the frequency modulation command, the AGC frequency modulation function is locked, and the frequency modulation command is determined to be the power deviation command value.

6. The method of claim 1, wherein the coordinated control mode further comprises a frequency locked AGC mode, the frequency locked AGC mode comprising a third locked sub-mode and a fourth locked sub-mode,

Wherein the power deviation command value is determined according to the frequency modulation command based on a locking mode corresponding to a frequency modulation locking AGC mode in which the AGC is located,

Wherein, in the third lockout sub-mode, the power deviation command value is determined by:

It is determined whether the frequency modulated instruction is zero,

If the frequency modulation command is zero, determining that the power deviation command value is zero,

If the frequency modulation command is not zero, then determining whether the AGC is in the process of frequency modulation exit,

If the AGC is in the process of frequency modulation exiting, determining the difference value between the current AGC power command and the power command before entering frequency modulation, determining the sum of the frequency modulation command and the difference value as a power deviation command value,

If the AGC is not in the process of the frequency modulation exit, the frequency modulation command is determined as a power deviation command value,

Wherein, in the fourth lockout sub-mode, the power deviation command value is determined by:

It is determined whether the frequency modulated instruction is zero,

If the frequency modulation command is not zero, a determination is made as to whether the historical AGC power offset value is zero when the AGC power command is zero,

If the historical AGC power bias value is not zero when the AGC power command is zero, the historical AGC power bias value is determined to be the current AGC power bias value,

If the historical AGC power offset value is zero when the AGC power command is zero, then it is determined whether the direction of the AGC power command coincides with the direction of the fm command,

If the direction of the AGC power command is consistent with the direction of the frequency modulation command, the AGC power command and the frequency modulation command are overlapped to obtain a power deviation command value,

If the direction of the AGC power command is inconsistent with the direction of the frequency modulation command, the frequency modulation command is determined to be a power deviation command value.

7. The method of claim 1, wherein the coordinated control mode further comprises a frequency modulated stacked AGC mode, the frequency modulated stacked AGC mode comprising a third stacked sub-mode and a fourth stacked sub-mode,

Wherein the power deviation command value is determined according to the frequency modulation command based on a superposition mode corresponding to a frequency modulation superposition AGC mode in which the AGC is positioned,

Wherein, in the third superposition sub mode, the power deviation command value is determined by:

determining whether the frequency modulation instruction is zero;

if the frequency modulation instruction is zero, determining that a power deviation instruction value is zero;

if the frequency modulation command is not zero, the AGC power command is overlapped with the frequency modulation command and the historical AGC power deviation value to obtain a power deviation command value,

Wherein, in the fourth superposition sub mode, the power deviation command value is determined by:

determining whether the frequency modulation instruction is zero;

If the frequency modulation command is not zero, determining whether a historical AGC power deviation value is zero when the AGC power command is zero;

If the historical AGC power deviation value is not zero when the AGC power command is zero, determining the historical AGC power deviation value as the current AGC power deviation value;

if the historical AGC power deviation value is zero when the AGC power command is zero, determining whether the direction of the AGC power command is consistent with the direction of the frequency modulation command;

If the direction of the AGC power instruction is consistent with the direction of the frequency modulation instruction, superposing the AGC power instruction with the frequency modulation instruction and the historical AGC power deviation value to obtain a power deviation instruction value;

and if the direction of the AGC power command is inconsistent with the direction of the frequency modulation command, superposing the frequency modulation command and the historical AGC power deviation value to obtain a power deviation command value.

8. A frequency modulation control device according to a frequency modulation control method of a wind farm according to any of claims 1-7, characterized in that the frequency modulation control device comprises:

The enabling module is used for starting a function of performing frequency modulation processing in a preset frequency modulation control mode aiming at the wind power plant based on the frequency modulation requirement of the wind power plant;

the frequency modulation instruction determining module is used for determining a frequency modulation instruction under the preset frequency modulation control mode based on the current frequency of the power grid;

The coordination control module is used for determining a coordination control mode of the AGC and the preset frequency modulation control mode;

the power deviation determining module is used for determining a power deviation instruction value according to the frequency modulation instruction based on the determined coordination control mode so as to carry out frequency modulation processing based on the determined power deviation instruction value;

The power deviation determining module is used for:

9. The frequency modulation control device of claim 8, wherein the frequency modulation control device is disposed in a wind farm controller.

10. A controller, comprising:

A processor;

Memory for storing a computer program which, when executed by the processor, implements a method of frequency modulation control of a wind farm according to any of claims 1 to 7.

11. A computer readable storage medium storing a computer program, characterized in that the computer program, when executed by a processor, implements a method of frequency modulation control of a wind farm according to any of claims 1 to 7.