Wind storage collaborative rapid frequency control method and device

Abstract

The invention relates to the technical field of new energy and energy storage grid-connected operation control, and particularly provides a wind storage collaborative fast frequency control method and device, and the method comprises the steps: determining the power which needs to be provided by a wind storage system for the fast frequency active support of a power grid based on the frequency deviation of a grid-connected point and the frequency change rate of the grid-connected point; adjusting the output of the wind storage system based on the power required to be provided by the wind storage system for performing the power grid rapid frequency active support until the power grid rapid frequency active support response is completed; controlling the wind driven generator to recover the rotating speed. According to the technical scheme provided by the invention, limited frequency modulation resources can be effectively utilized, the maximization of the active frequency supporting capability in the new energy high-proportion power grid is realized, and meanwhile, the problem of frequency secondary drop possibly occurring in the new energy high-proportion power grid is effectively inhibited by controlling the wind driven generator to recover the rotating speed.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy and energy storage grid-connected operation control, and in particular to a wind-storage coordinated rapid frequency control method and device. Background Art

[0002] Vigorously developing new energy plays a vital role in responding to energy and climate development trends. However, it is necessary to recognize that its own characteristics also bring many challenges to the safe and stable operation of the power grid. In traditional power grids, the realization of frequency stability depends on traditional synchronous generator sets with hydropower or thermal power as the main energy source. Since synchronous generators have rotational inertia, their speed has a natural coupling relationship with the grid frequency. Therefore, when there are disturbances such as sudden load increase or tripping of some generators in the grid, resulting in an increase in active power demand, they can provide short-term active power support by releasing rotor kinetic energy; secondly, since the synchronous generators in the power grid have sufficient spare capacity reserved for frequency regulation, they can cope with the long-term energy consumption caused by active power disturbances through primary and secondary frequency regulation. Unlike synchronous generators, the basic principle of existing wind power and photovoltaic power generation is to adjust the output of wind turbines to synchronize with the power grid through power electronic conversion technology. Since their rotors are connected to the power grid through power electronic conversion devices, their speed is decoupled from the power grid frequency and cannot provide inertia support for the power grid by releasing rotor kinetic energy like traditional synchronous machines. In addition, in order to maximize the utilization of wind energy and solar energy, they usually operate in the maximum power point tracking (MPPT) state, without reserved active spare capacity, and therefore do not have the frequency regulation capability of traditional synchronous machines. With the large-scale grid connection of new energy and the gradual replacement of traditional synchronous generators, the equivalent inertia of the power system continues to decrease, and the frequency regulation capability deteriorates, posing a threat to the frequency stability of the system.

[0003] As a disruptive low-carbon technology, energy storage technology plays an important role in flexibility regulation in new power systems and provides a new solution to the problem of new energy development. With its fast charging and discharging and flexible scheduling characteristics, it can effectively alleviate the power fluctuation and uncertainty problems caused by the grid connection of renewable energy and improve the grid's ability to absorb renewable energy. Configuring an appropriate amount of energy storage system in new energy power stations can improve the inertia level and frequency response capability of the power system, quickly release energy when the grid frequency drops, and quickly absorb energy when the frequency rises, simulating the inertia response and primary frequency regulation function of traditional synchronous generator sets, significantly improving the frequency stability of high-proportion new energy power systems, and reducing the safety risks of grid operation.

[0004] The fast frequency active support of the wind storage system includes virtual inertia control and primary frequency regulation control, which adjust the output power according to the frequency change rate and frequency change amount of the grid connection point respectively. "Fast frequency response" is used by the power industry to describe the behavioral characteristics of synchronous generator sets after load fluctuations in the power system. For doubly fed wind turbines whose rotor speed cannot respond to changes in grid frequency, how to make them have the frequency response characteristics of synchronous motors and meet the frequency regulation requirements of wind farms is a scientific and technological problem that researchers have studied in depth and worked hard to solve in recent years. Summary of the invention

[0005] In order to overcome the above-mentioned defects, the present invention proposes a wind-storage coordinated rapid frequency control method and device.

[0006] In a first aspect, a wind-storage coordinated rapid frequency control method is provided, the wind-storage coordinated rapid frequency control method comprising:

[0007] Determine the power that the wind storage system needs to provide for active support of the grid's rapid frequency based on the grid connection point frequency deviation and grid connection point frequency change rate;

[0008] Adjust the output of the wind storage system based on the power required for the wind storage system to provide active support for the rapid frequency of the power grid until the active support response for the rapid frequency of the power grid is completed;

[0009] Control the wind turbine to recover the speed.

[0010] Preferably, the method of determining the power required to be provided by the wind storage system for active support of the grid fast frequency based on the grid connection point frequency deviation and the grid connection point frequency change rate includes:

[0011] Determine the power required to respond to a disturbance in the power grid due to the frequency deviation based on the frequency deviation of the grid connection point;

[0012] Determine the power required to respond to a disturbance in the power grid based on the frequency change rate of the grid connection point;

[0013] The power that the wind storage system needs to provide for active support of the grid's rapid frequency is determined based on the power that needs to respond to the grid's frequency deviation disturbance and the power that needs to respond to the grid's frequency change rate disturbance.

[0014] Furthermore, the frequency deviation of the grid connection point is as follows:

[0015] △f=ff N

[0016] The frequency change rate of the grid connection point is as follows:

[0017] △f J =△f / △T

[0018] In the above formula, △f is the grid connection point frequency deviation, f is the grid connection point frequency of the wind storage system, and f N is the rated frequency of the power grid, △f J is the frequency change rate of the grid connection point, and △T is the frequency sampling period.

[0019] Furthermore, when Δf>0, the power required to respond to the frequency deviation power grid after being disturbed is as follows:

[0020] △P f =-(K f (△ff s ) N ) / f N

[0021] When △f<0, the power required to respond to the frequency deviation after the grid is disturbed is as follows:

[0022] △P f =-(K f (△f+f s ) N ) / f N

[0023] In the above formula, △P f K is the power required to respond to the frequency deviation after the grid is disturbed. f is the primary frequency modulation coefficient of the wind-storage system, f s is the fast frequency response action threshold, P N Installed capacity of wind farm.

[0024] Furthermore, the power required to respond to the disturbance of the power grid according to the frequency change rate is as follows:

[0025] △P J =-(T J △f J P N ) / f N

[0026] In the above formula, △P J T is the power required to respond to the frequency change rate after the grid is disturbed, J is the inertia time constant of the wind energy storage system, P N Installed capacity of wind farm.

[0027] Furthermore, the power required to be provided by the wind storage system for active support of the grid fast frequency based on the power required to respond to the frequency deviation grid after being disturbed and the power required to respond to the frequency change rate grid after being disturbed includes:

[0028] When △P f >0 and △PJ >0, △P=△P f +△P J , when △P f >0 and △P J <0, △P=△P f ;

[0029] When △P f <0 and △P J >0, △P=△P f , when △P f <0 and △P J <0, △P=△P f +△P J ;

[0030] Among them, △P is the power that the wind storage system needs to provide for active support of the grid's rapid frequency.

[0031] Preferably, the step of adjusting the output of the wind storage system based on the power required to be provided by the wind storage system for active support of the rapid frequency of the power grid until the active support response of the rapid frequency of the power grid is completed includes:

[0032] When △P<0, reduce the output of the wind-storage system until the output reduction of the wind-storage system is equal to △P;

[0033] When △P>0, increase the output of the wind-storage system until the increase in the output of the wind-storage system is equal to △P.

[0034] Furthermore, the control strategy corresponding to reducing the output of the wind storage system includes at least one of the following: controlling the energy storage to reduce the discharge power or increase the charging power, controlling the wind turbine to accelerate the storage of rotor kinetic energy until the wind turbine reaches the maximum speed, and adjusting the operation mode of the wind turbine to the power limiting mode until the output of the wind turbine reaches the minimum output;

[0035] Among them, the priority of controlling energy storage to reduce discharge power or increase charging power is greater than the priority of controlling the wind turbine to accelerate the storage of rotor kinetic energy until the wind turbine reaches the maximum speed, and the priority of adjusting the operation mode of the wind turbine to the limited power mode until the wind turbine output reaches the minimum output.

[0036] Further, when the operation mode of the wind turbine is the limited power mode, the control strategy corresponding to increasing the output of the wind storage system includes at least one of the following: controlling the wind turbine to increase the output to the MPPT power, controlling the energy storage to reduce the charging power or increase the discharging power, and controlling the wind turbine to decelerate and release the rotor kinetic energy until the wind turbine reaches the minimum speed;

[0037] Among them, the priority of controlling the wind turbine to increase the output to the MPPT power is greater than the priority of controlling the energy storage to reduce the charging power or increase the discharging power, and is greater than the priority of controlling the wind turbine to decelerate and release the rotor kinetic energy until the wind turbine reaches the minimum speed.

[0038] Further, when the operation mode of the wind turbine is the MPPT mode, the control strategy corresponding to increasing the output of the wind storage system includes at least one of the following: controlling the energy storage to reduce the charging power or increase the discharging power, controlling the wind turbine to decelerate and release the rotor kinetic energy until the wind turbine reaches the minimum speed;

[0039] Among them, the priority of controlling energy storage to reduce charging power or increase discharging power is greater than the priority of controlling the wind turbine to decelerate and release rotor kinetic energy until the wind turbine reaches the minimum speed.

[0040] Furthermore, controlling the wind turbine generator to recover the rotation speed includes:

[0041] When △P<0, the operation mode of the wind turbine is controlled to be MPPT mode;

[0042] When △P>0, the operation mode of the wind turbine generator before the grid fast frequency active support response is the MPPT mode and the remaining discharge power of the energy storage is greater than △P1, the operation mode of the wind turbine generator is controlled to the MPPT mode, and the energy storage is restored to the working state before the grid fast frequency active support response;

[0043] When △P>0, the wind turbine is in MPPT mode before the grid's fast frequency active support response and the remaining discharge power of the energy storage is less than △P1, the wind turbine output is first adjusted to 90% of the mechanical power captured by the wind rotor, and then the wind turbine output is adjusted to be equal to the MPPT power;

[0044] When △P>0, the operation mode of the wind turbine before the grid fast frequency active support response is the power limit mode, the current speed of the wind turbine is less than the speed before the grid fast frequency active support response, and the remaining discharge power of the energy storage is greater than △P1, the operation mode of the wind turbine is controlled to be the MPPT mode, and the energy storage is restored to the working state before the grid fast frequency active support response;

[0045] When △P>0, the operation mode of the wind turbine before the grid fast frequency active support response is the power limit mode, the current speed of the wind turbine is less than the speed before the grid fast frequency active support response and the remaining discharge power of the energy storage is less than △P1, first adjust the wind turbine output to 90% of the mechanical power captured by the wind wheel, and then adjust the wind turbine output to be equal to the command power;

[0046] Among them, △P1 is the difference between the output of the wind turbine at the moment before the end of the grid fast frequency active support response and the MPPT power.

[0047] Furthermore, the wind wheel captures mechanical power as follows:

[0048]

[0049] In the above formula, P m is the mechanical power captured by the wind wheel, R is the radius of the wind wheel, ρ is the air density, υ ω is the actual wind speed, C p is the wind energy utilization coefficient.

[0050] Furthermore, the MPPT power is as follows:

[0051]

[0052] In the above formula, P opt is the MPPT power, λ max is the maximum tip speed ratio, C p,max is the maximum value of wind energy utilization coefficient, ω opt is the optimal speed, k opt is the proportional coefficient of the MPPT curve.

[0053] In a second aspect, a wind-storage coordinated rapid frequency control device is provided, the wind-storage coordinated rapid frequency control device comprising:

[0054] A determination module, used to determine the power that the wind storage system needs to provide for active support of the grid fast frequency based on the grid connection point frequency deviation and the grid connection point frequency change rate;

[0055] An adjustment module, used to adjust the output of the wind storage system based on the power required to be provided by the wind storage system for active support of the rapid frequency of the power grid until the active support response of the rapid frequency of the power grid is completed;

[0056] The recovery module is used to control the wind turbine to recover the speed.

[0057] In a third aspect, a computer device is provided, comprising: one or more processors;

[0058] The processor is configured to execute one or more programs;

[0059] When the one or more programs are executed by the one or more processors, the wind-storage coordinated rapid frequency control method is implemented.

[0060] In a fourth aspect, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed, the wind-storage coordinated rapid frequency control method is implemented.

[0061] The above one or more technical solutions of the present invention have at least one or more of the following beneficial effects:

[0062] The present invention provides a method and device for rapid frequency control in coordination with wind and storage, including: determining the power required for the wind storage system to actively support the rapid frequency of the power grid based on the frequency deviation of the grid connection point and the frequency change rate of the grid connection point; adjusting the output of the wind storage system based on the power required for the wind storage system to actively support the rapid frequency of the power grid until the rapid frequency active support response of the power grid is completed; and controlling the wind turbine to recover the speed. The technical solution provided by the present invention can effectively utilize limited frequency modulation resources to maximize the active frequency support capability in a power grid with a high proportion of new energy, and at the same time, by controlling the wind turbine to recover the speed, it can effectively suppress the secondary frequency drop problem that may occur in a power grid with a high proportion of new energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 This is a schematic flow chart of the main steps of the wind-storage coordinated rapid frequency control method according to an embodiment of the present invention;

[0064] Figure 2 It is an MPPT curve diagram of the wind turbine generator under different wind speeds according to an embodiment of the present invention. DETAILED DESCRIPTION

[0065] The specific implementation modes of the present invention will be further described in detail below in conjunction with the accompanying drawings.

[0066] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0067] Example 1

[0068] See attached Figure 1 , Figure 1 FIG. 1 is a flow chart showing the main steps of a wind-storage coordinated rapid frequency control method according to an embodiment of the present invention. Figure 1 As shown, the wind-storage coordinated rapid frequency control method in the embodiment of the present invention mainly includes the following steps:

[0069] Step S101: determining the power that the wind storage system needs to provide for active grid fast frequency support based on the grid connection point frequency deviation and the grid connection point frequency change rate;

[0070] Step S102: adjusting the output of the wind storage system based on the power required to be provided by the wind storage system for active support of the rapid frequency of the power grid until the active support response of the rapid frequency of the power grid is completed;

[0071] Step S103: controlling the wind turbine generator to restore the rotation speed.

[0072] In this embodiment, the power required to be provided by the wind storage system for active support of the grid fast frequency based on the grid connection point frequency deviation and the grid connection point frequency change rate is determined, including:

[0073] Determine the power required to respond to a disturbance in the power grid due to the frequency deviation based on the frequency deviation of the grid connection point;

[0074] Determine the power required to respond to a disturbance in the power grid based on the frequency change rate of the grid connection point;

[0075] The power that the wind storage system needs to provide for active support of the grid's rapid frequency is determined based on the power that needs to respond to the grid's frequency deviation disturbance and the power that needs to respond to the grid's frequency change rate disturbance.

[0076] In one embodiment, the grid connection point frequency deviation is as follows:

[0077] △f=ff N

[0078] The frequency change rate of the grid connection point is as follows:

[0079] △f J =△f / △T

[0080] In the above formula, △f is the grid connection point frequency deviation, f is the grid connection point frequency of the wind storage system, and f N is the rated frequency of the power grid, △f J is the frequency change rate of the grid connection point, and △T is the frequency sampling period.

[0081] In one embodiment, when Δf>0, the power required to respond to the frequency deviation power grid after being disturbed is as follows:

[0082] △P f =-(K f (△ff s ) N ) / f N

[0083] When △f<0, the power required to respond to the frequency deviation after the grid is disturbed is as follows:

[0084] △P f =-(K f (△f+f s )N ) / f N

[0085] In the above formula, △P f K is the power required to respond to the frequency deviation after the grid is disturbed. f is the primary frequency modulation coefficient of the wind-storage system, f s is the fast frequency response action threshold, P N Installed capacity of wind farm.

[0086] In one embodiment, the power required to respond to a disturbance in the power grid with respect to the frequency change rate is as follows:

[0087] △P J =-(T J △f J P N ) / f N

[0088] In the above formula, △P J T is the power required to respond to the frequency change rate after the grid is disturbed, J is the inertia time constant of the wind energy storage system, P N Installed capacity of wind farm.

[0089] In one embodiment, the power required to be provided by the wind storage system for active support of the grid fast frequency based on the power required to respond to the frequency deviation after the grid is disturbed and the power required to respond to the frequency change rate after the grid is disturbed includes:

[0090] When △P f >0 and △P J >0, △P=△P f +△P J , when △P f >0 and △P J <0, △P=△P f ;

[0091] When △P f <0 and △P J >0, △P=△P f , when △P f <0 and △P J <0, △P=△P f +△P J ;

[0092] Among them, △P is the power that the wind storage system needs to provide for active support of the grid's rapid frequency.

[0093] In this embodiment, the power required to be provided by the wind-storage system for active support of the grid fast frequency is adjusted based on the wind-storage system until the active support response of the grid fast frequency is completed, including:

[0094] When △P<0, reduce the output of the wind-storage system until the output reduction of the wind-storage system is equal to △P;

[0095] When △P>0, increase the output of the wind-storage system until the increase in the output of the wind-storage system is equal to △P.

[0096] In one embodiment, the control strategy corresponding to reducing the output of the wind storage system includes at least one of the following: controlling the energy storage to reduce the discharge power or increase the charging power, controlling the wind turbine to accelerate the storage of rotor kinetic energy until the wind turbine reaches the maximum speed, and adjusting the operation mode of the wind turbine to the power limiting mode until the output of the wind turbine reaches the minimum output;

[0097] Among them, the priority of controlling energy storage to reduce discharge power or increase charging power is greater than the priority of controlling the wind turbine to accelerate the storage of rotor kinetic energy until the wind turbine reaches the maximum speed, and the priority of adjusting the operation mode of the wind turbine to the limited power mode until the wind turbine output reaches the minimum output.

[0098] In one embodiment, when the operation mode of the wind turbine is the limited power mode, the control strategy corresponding to increasing the output of the wind storage system includes at least one of the following: controlling the wind turbine to increase the output to the MPPT power, controlling the energy storage to reduce the charging power or increase the discharging power, and controlling the wind turbine to decelerate and release the rotor kinetic energy until the wind turbine reaches the minimum speed;

[0099] Among them, the priority of controlling the wind turbine to increase the output to the MPPT power is greater than the priority of controlling the energy storage to reduce the charging power or increase the discharging power, and is greater than the priority of controlling the wind turbine to decelerate and release the rotor kinetic energy until the wind turbine reaches the minimum speed.

[0100] In one embodiment, when the operation mode of the wind turbine is the MPPT mode, the control strategy corresponding to increasing the output of the wind storage system includes at least one of the following: controlling the energy storage to reduce the charging power or increase the discharging power, controlling the wind turbine to decelerate and release the rotor kinetic energy until the wind turbine reaches the minimum speed;

[0101] Among them, the priority of controlling energy storage to reduce charging power or increase discharging power is greater than the priority of controlling the wind turbine to decelerate and release rotor kinetic energy until the wind turbine reaches the minimum speed.

[0102] In one embodiment, controlling the wind turbine to recover the rotation speed includes:

[0103] When △P<0, the operation mode of the wind turbine is controlled to be MPPT mode;

[0104] When △P>0, the operation mode of the wind turbine generator before the grid fast frequency active support response is the MPPT mode and the remaining discharge power of the energy storage is greater than △P1, the operation mode of the wind turbine generator is controlled to the MPPT mode, and the energy storage is restored to the working state before the grid fast frequency active support response;

[0105] When △P>0, the wind turbine is in MPPT mode before the grid's fast frequency active support response and the remaining discharge power of the energy storage is less than △P1, the wind turbine output is first adjusted to 90% of the mechanical power captured by the wind rotor, and then the wind turbine output is adjusted to be equal to the MPPT power;

[0106] When △P>0, the operation mode of the wind turbine before the grid fast frequency active support response is the power limit mode, the current speed of the wind turbine is less than the speed before the grid fast frequency active support response, and the remaining discharge power of the energy storage is greater than △P1, the operation mode of the wind turbine is controlled to be the MPPT mode, and the energy storage is restored to the working state before the grid fast frequency active support response;

[0107] When △P>0, the operation mode of the wind turbine before the grid fast frequency active support response is the power limit mode, the current speed of the wind turbine is less than the speed before the grid fast frequency active support response and the remaining discharge power of the energy storage is less than △P1, first adjust the wind turbine output to 90% of the mechanical power captured by the wind wheel, and then adjust the wind turbine output to be equal to the command power;

[0108] Among them, △P1 is the difference between the output of the wind turbine at the moment before the end of the grid fast frequency active support response and the MPPT power.

[0109] In one embodiment, the wind wheel captures mechanical power as follows:

[0110]

[0111] In the above formula, P m is the mechanical power captured by the wind wheel, R is the radius of the wind wheel, ρ is the air density, υ ω is the actual wind speed, C p is the wind energy utilization coefficient.

[0112] In one embodiment, the MPPT power is as follows:

[0113]

[0114] In the above formula, P opt is the MPPT power, λmax is the maximum tip speed ratio, C p,max is the maximum value of wind energy utilization coefficient, ω opt is the optimal speed, k opt is the proportional coefficient of the MPPT curve. The MPPT curve at different wind speeds is shown in the figure below. Figure 2 As shown in the figure, v1 to v5 represent 5 different wind speeds, ω w is the real-time speed of the wind turbine.

[0115] Example 2

[0116] Based on the same inventive concept, the present invention also provides a wind-storage coordinated rapid frequency control device, the wind-storage coordinated rapid frequency control device comprising:

[0117] A determination module, used to determine the power that the wind storage system needs to provide for active support of the grid fast frequency based on the grid connection point frequency deviation and the grid connection point frequency change rate;

[0118] An adjustment module, used to adjust the output of the wind storage system based on the power required to be provided by the wind storage system for active support of the rapid frequency of the power grid until the active support response of the rapid frequency of the power grid is completed;

[0119] The recovery module is used to control the wind turbine to recover the speed.

[0120] Preferably, the method of determining the power required to be provided by the wind storage system for active support of the grid fast frequency based on the grid connection point frequency deviation and the grid connection point frequency change rate includes:

[0121] Determine the power required to respond to a disturbance in the power grid due to the frequency deviation based on the frequency deviation of the grid connection point;

[0122] Determine the power required to respond to a disturbance in the power grid based on the frequency change rate of the grid connection point;

[0123] The power that the wind storage system needs to provide for active support of the grid's rapid frequency is determined based on the power that needs to respond to the grid's frequency deviation disturbance and the power that needs to respond to the grid's frequency change rate disturbance.

[0124] Furthermore, the frequency deviation of the grid connection point is as follows:

[0125] △f=ff N

[0126] The frequency change rate of the grid connection point is as follows:

[0127] △f J =△f / △T

[0128] In the above formula, △f is the grid connection point frequency deviation, f is the grid connection point frequency of the wind storage system, and fN is the rated frequency of the power grid, △f J is the frequency change rate of the grid connection point, and △T is the frequency sampling period.

[0129] Furthermore, when Δf>0, the power required to respond to the frequency deviation power grid after being disturbed is as follows:

[0130] △P f =-(K f (△ff s ) N ) / f N

[0131] When △f<0, the power required to respond to the frequency deviation after the grid is disturbed is as follows:

[0132] △P f =-(K f (△f+f s ) N ) / f N

[0133] In the above formula, △P f K is the power required to respond to the frequency deviation after the grid is disturbed. f is the primary frequency modulation coefficient of the wind-storage system, f s is the fast frequency response action threshold, P N Installed capacity of wind farm.

[0134] Furthermore, the power required to respond to the disturbance of the power grid according to the frequency change rate is as follows:

[0135] △P J =-(T J △f J P N ) / f N

[0136] In the above formula, △P J T is the power required to respond to the frequency change rate after the grid is disturbed, J is the inertia time constant of the wind energy storage system, P N Installed capacity of wind farm.

[0137] Furthermore, the power required to be provided by the wind storage system for active support of the grid fast frequency based on the power required to respond to the frequency deviation grid after being disturbed and the power required to respond to the frequency change rate grid after being disturbed includes:

[0138] When △P f >0 and △P J >0, △P=△P f +△PJ , when △P f >0 and △P J <0, △P=△P f ;

[0139] When △P f <0 and △P J >0, △P=△P f , when △P f <0 and △P J <0, △P=△P f +△P J ;

[0140] Among them, △P is the power that the wind storage system needs to provide for active support of the grid's rapid frequency.

[0141] Preferably, the step of adjusting the output of the wind storage system based on the power required to be provided by the wind storage system for active support of the rapid frequency of the power grid until the active support response of the rapid frequency of the power grid is completed includes:

[0142] When △P<0, reduce the output of the wind-storage system until the output reduction of the wind-storage system is equal to △P;

[0143] When △P>0, increase the output of the wind-storage system until the increase in the output of the wind-storage system is equal to △P.

[0144] Furthermore, the control strategy corresponding to reducing the output of the wind storage system includes at least one of the following: controlling the energy storage to reduce the discharge power or increase the charging power, controlling the wind turbine to accelerate the storage of rotor kinetic energy until the wind turbine reaches the maximum speed, and adjusting the operation mode of the wind turbine to the power limiting mode until the output of the wind turbine reaches the minimum output;

[0145] Among them, the priority of controlling energy storage to reduce discharge power or increase charging power is greater than the priority of controlling the wind turbine to accelerate the storage of rotor kinetic energy until the wind turbine reaches the maximum speed, and the priority of adjusting the operation mode of the wind turbine to the limited power mode until the wind turbine output reaches the minimum output.

[0146] Further, when the operation mode of the wind turbine is the limited power mode, the control strategy corresponding to increasing the output of the wind storage system includes at least one of the following: controlling the wind turbine to increase the output to the MPPT power, controlling the energy storage to reduce the charging power or increase the discharging power, and controlling the wind turbine to decelerate and release the rotor kinetic energy until the wind turbine reaches the minimum speed;

[0147] Among them, the priority of controlling the wind turbine to increase the output to the MPPT power is greater than the priority of controlling the energy storage to reduce the charging power or increase the discharging power, and is greater than the priority of controlling the wind turbine to decelerate and release the rotor kinetic energy until the wind turbine reaches the minimum speed.

[0148] Further, when the operation mode of the wind turbine is the MPPT mode, the control strategy corresponding to increasing the output of the wind storage system includes at least one of the following: controlling the energy storage to reduce the charging power or increase the discharging power, controlling the wind turbine to decelerate and release the rotor kinetic energy until the wind turbine reaches the minimum speed;

[0149] Among them, the priority of controlling energy storage to reduce charging power or increase discharging power is greater than the priority of controlling the wind turbine to decelerate and release rotor kinetic energy until the wind turbine reaches the minimum speed.

[0150] Furthermore, controlling the wind turbine generator to recover the rotation speed includes:

[0151] When △P<0, the operation mode of the wind turbine is controlled to be MPPT mode;

[0152] When △P>0, the operation mode of the wind turbine generator before the grid fast frequency active support response is the MPPT mode and the remaining discharge power of the energy storage is greater than △P1, the operation mode of the wind turbine generator is controlled to the MPPT mode, and the energy storage is restored to the working state before the grid fast frequency active support response;

[0153] When △P>0, the wind turbine is in MPPT mode before the grid's fast frequency active support response and the remaining discharge power of the energy storage is less than △P1, the wind turbine output is first adjusted to 90% of the mechanical power captured by the wind rotor, and then the wind turbine output is adjusted to be equal to the MPPT power;

[0154] When △P>0, the operation mode of the wind turbine before the grid fast frequency active support response is the power limit mode, the current speed of the wind turbine is less than the speed before the grid fast frequency active support response, and the remaining discharge power of the energy storage is greater than △P1, the operation mode of the wind turbine is controlled to be the MPPT mode, and the energy storage is restored to the working state before the grid fast frequency active support response;

[0155] When △P>0, the operation mode of the wind turbine before the grid fast frequency active support response is the power limit mode, the current speed of the wind turbine is less than the speed before the grid fast frequency active support response and the remaining discharge power of the energy storage is less than △P1, first adjust the wind turbine output to 90% of the mechanical power captured by the wind wheel, and then adjust the wind turbine output to be equal to the command power;

[0156] Among them, △P1 is the difference between the output of the wind turbine at the moment before the end of the grid fast frequency active support response and the MPPT power.

[0157] Furthermore, the wind wheel captures mechanical power as follows:

[0158]

[0159] In the above formula, P m is the mechanical power captured by the wind wheel, R is the radius of the wind wheel, ρ is the air density, υ ω is the actual wind speed, C p is the wind energy utilization coefficient.

[0160] Furthermore, the MPPT power is as follows:

[0161]

[0162] In the above formula, P opt is the MPPT power, λ max is the maximum tip speed ratio, C p,max is the maximum value of wind energy utilization coefficient, ω opt is the optimal speed, k opt is the proportional coefficient of the MPPT curve.

[0163] Example 3

[0164] Based on the same inventive concept, the present invention also provides a computer device, which includes a processor and a memory, wherein the memory is used to store a computer program, the computer program includes program instructions, and the processor is used to execute the program instructions stored in the computer storage medium. The processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, which is suitable for implementing one or more instructions, and is specifically suitable for loading and executing one or more instructions in a computer storage medium to implement the corresponding method flow or corresponding function, so as to implement the steps of a wind storage coordinated rapid frequency control method in the above embodiment.

[0165] Example 4

[0166] Based on the same inventive concept, the present invention also provides a storage medium, specifically a computer-readable storage medium (Memory), which is a memory device in a computer device for storing programs and data. It can be understood that the computer-readable storage medium here can include both built-in storage media in a computer device and, of course, extended storage media supported by the computer device. The computer-readable storage medium provides a storage space, which stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by a processor are also stored in the storage space, and these instructions can be one or more computer programs (including program codes). It should be noted that the computer-readable storage medium here can be a high-speed RAM memory or a non-volatile memory, such as at least one disk memory. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the steps of a wind storage coordinated rapid frequency control method in the above embodiment.

[0167] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0168] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0169] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1A function specified in one or more boxes.

[0170] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0171] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A wind-storage coordinated rapid frequency control method, characterized in that: The method comprises: Determine the power that the wind storage system needs to provide for active support of the grid's rapid frequency based on the grid connection point frequency deviation and grid connection point frequency change rate; Adjust the output of the wind storage system based on the power required for the wind storage system to provide active support for the rapid frequency of the power grid until the active support response for the rapid frequency of the power grid is completed; Control the wind turbine to recover the speed.

2. The method according to claim 1, characterized in that The method of determining the power required to be provided by the wind storage system for active support of the grid fast frequency based on the grid connection point frequency deviation and the grid connection point frequency change rate includes: Determine the power required to respond to a disturbance in the power grid due to the frequency deviation based on the frequency deviation of the grid connection point; Determine the power required to respond to a disturbance in the power grid based on the frequency change rate of the grid connection point; The power that the wind storage system needs to provide for active support of the grid's rapid frequency is determined based on the power that needs to respond to the grid's frequency deviation disturbance and the power that needs to respond to the grid's frequency change rate disturbance.

3. The method according to claim 2, characterized in that The grid connection point frequency deviation is as follows: △f=f-f N The frequency change rate of the grid connection point is as follows: △f J =△f / △T In the above formula, △f is the grid connection point frequency deviation, f is the grid connection point frequency of the wind storage system, and f N is the rated frequency of the power grid, △f J is the frequency change rate of the grid connection point, and △T is the frequency sampling period.

4. The method according to claim 3, characterized in that When △f>0, the power required to respond to the frequency deviation after the grid is disturbed is as follows: △P f =-(K f (△f-f s )P N ) / f N When △f<0, the power required to respond to the frequency deviation after the grid is disturbed is as follows: △P f =-(K f (△f+f s )P N ) / f N In the above formula, △P f K is the power required to respond to the frequency deviation after the grid is disturbed. f is the primary frequency modulation coefficient of the wind-storage system, f s is the fast frequency response action threshold, P N Installed capacity of wind farm.

5. The method according to claim 4, characterized in that The power required to respond to the disturbance of the frequency change rate grid is as follows: △P J =-(T J △f J P N ) / f N In the above formula, △P J T is the power required to respond to the frequency change rate after the grid is disturbed, J is the inertia time constant of the wind energy storage system, P N Installed capacity of wind farm.

6. The method according to claim 5, characterized in that The method of determining the power required to be provided by the wind storage system for active support of the grid fast frequency based on the power required to respond to the frequency deviation grid after being disturbed and the power required to respond to the frequency change rate grid after being disturbed includes: When △P f >0 and △P J >0, △P=△P f +△P J , when △P f >0 and △P J <0, △P=△P f ; When △P f <0 and △P J >0, △P=△P f , when △P f <0 and △P J <0, △P=△P f +△P J ; Among them, △P is the power that the wind storage system needs to provide for active support of the grid's rapid frequency.

7. The method according to claim 1, characterized in that The power adjustment of the wind storage system output based on the wind storage system for active support of the grid fast frequency needs to be provided until the active support response of the grid fast frequency is completed, including: When △P<0, reduce the output of the wind-storage system until the output reduction of the wind-storage system is equal to △P; When △P>0, increase the output of the wind-storage system until the increase in the output of the wind-storage system is equal to △P.

8. The method according to claim 7, characterized in that The control strategy corresponding to reducing the output of the wind storage system includes at least one of the following: controlling the energy storage to reduce the discharge power or increase the charging power, controlling the wind generator to accelerate the storage of rotor kinetic energy until the wind generator reaches the maximum speed, and adjusting the operation mode of the wind generator to the power limiting mode until the output of the wind generator reaches the minimum output; Among them, the priority of controlling energy storage to reduce discharge power or increase charging power is greater than the priority of controlling the wind turbine to accelerate the storage of rotor kinetic energy until the wind turbine reaches the maximum speed, and the priority of adjusting the operation mode of the wind turbine to the limited power mode until the wind turbine output reaches the minimum output.

9. The method according to claim 8, characterized in that When the operation mode of the wind turbine is the limited power mode, the control strategy corresponding to increasing the output of the wind storage system includes at least one of the following: controlling the wind turbine to increase the output to the MPPT power, controlling the energy storage to reduce the charging power or increase the discharging power, and controlling the wind turbine to decelerate and release the rotor kinetic energy until the wind turbine reaches the minimum speed; Among them, the priority of controlling the wind turbine to increase the output to the MPPT power is greater than the priority of controlling the energy storage to reduce the charging power or increase the discharging power, and is greater than the priority of controlling the wind turbine to decelerate and release the rotor kinetic energy until the wind turbine reaches the minimum speed.

10. The method according to claim 8, characterized in that When the operation mode of the wind turbine is the MPPT mode, the control strategy corresponding to increasing the output of the wind storage system includes at least one of the following: controlling the energy storage to reduce the charging power or increase the discharging power, controlling the wind turbine to decelerate and release the rotor kinetic energy until the wind turbine reaches the minimum speed; Among them, the priority of controlling energy storage to reduce charging power or increase discharging power is greater than the priority of controlling the wind turbine to decelerate and release rotor kinetic energy until the wind turbine reaches the minimum speed.

11. The method according to claim 7, characterized in that The controlling the wind turbine generator to restore the rotation speed comprises: When △P<0, the operation mode of the wind turbine is controlled to be MPPT mode; When △P>0, the operation mode of the wind turbine generator before the grid fast frequency active support response is the MPPT mode and the remaining discharge power of the energy storage is greater than △P1, the operation mode of the wind turbine generator is controlled to the MPPT mode, and the energy storage is restored to the working state before the grid fast frequency active support response; When △P>0, the wind turbine is in MPPT mode before the grid's fast frequency active support response and the remaining discharge power of the energy storage is less than △P1, the wind turbine output is first adjusted to 90% of the mechanical power captured by the wind rotor, and then the wind turbine output is adjusted to be equal to the MPPT power; When △P>0, the operation mode of the wind turbine before the grid fast frequency active support response is the power limit mode, the current speed of the wind turbine is less than the speed before the grid fast frequency active support response, and the remaining discharge power of the energy storage is greater than △P1, the operation mode of the wind turbine is controlled to be the MPPT mode, and the energy storage is restored to the working state before the grid fast frequency active support response; When △P>0, the operation mode of the wind turbine before the grid fast frequency active support response is the power limit mode, the current speed of the wind turbine is less than the speed before the grid fast frequency active support response and the remaining discharge power of the energy storage is less than △P1, first adjust the wind turbine output to 90% of the mechanical power captured by the wind wheel, and then adjust the wind turbine output to be equal to the command power; Among them, △P1 is the difference between the output of the wind turbine at the moment before the end of the grid fast frequency active support response and the MPPT power.

12. The method according to claim 11, characterized in that The wind wheel captures mechanical power as follows: In the above formula, P m is the mechanical power captured by the wind wheel, R is the radius of the wind wheel, ρ is the air density, υ ω is the actual wind speed, C p is the wind energy utilization coefficient.

13. The method according to claim 12, characterized in that The MPPT power is as follows: In the above formula, P opt is the MPPT power, λ max is the maximum tip speed ratio, C p,max is the maximum value of wind energy utilization coefficient, ω opt is the optimal speed, k opt is the proportional coefficient of the MPPT curve.

14. A device based on the wind-storage coordinated rapid frequency control method according to any one of claims 1 to 13, characterized in that: The device comprises: A determination module, used to determine the power that the wind storage system needs to provide for active support of the grid fast frequency based on the grid connection point frequency deviation and the grid connection point frequency change rate; An adjustment module, used to adjust the output of the wind storage system based on the power required to be provided by the wind storage system for active support of the rapid frequency of the power grid until the active support response of the rapid frequency of the power grid is completed; The recovery module is used to control the wind turbine to recover the speed.

15. A computer device, characterized in that: include: one or more processors; The processor is configured to execute one or more programs; When the one or more programs are executed by the one or more processors, the wind-storage coordinated rapid frequency control method as described in any one of claims 1 to 13 is implemented.

16. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the computer program is executed, the wind-storage coordinated rapid frequency control method as described in any one of claims 1 to 13 is implemented.

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