Frequency adjusting method and device of power system, controller and power system

Abstract

The invention discloses a frequency adjustment method and device of a power system, a controller and the power system, and belongs to the field of new energy power. The method comprises the following steps: under the condition of determining to enter a frequency modulation stage, obtaining an active power total regulation quantity based on a frequency modulation parameter and a preset frequency and power droop control characteristic model; according to the power regulation capability parameters of the new energy devices, the power regulation capability parameters of the energy storage units and the power influence parameters of the new energy devices, splitting the total active power regulation quantity, and obtaining the active power regulation quantity of each new energy device and the active power regulation quantity of each energy storage unit, the power influence parameter is positively correlated with the active power adjusting quantity of the new energy device; and controlling each new energy device to operate according to the corresponding active power adjusting quantity, and controlling each energy storage unit to operate according to the corresponding active power adjusting quantity so as to realize frequency adjustment. According to the embodiment of the invention, the overall frequency modulation response capability of the power system can be improved.

Description

Technical Field

[0001] The present application relates to the field of renewable energy and electricity, and in particular to a frequency regulation method, device, controller and power system for a power system. Background Art

[0002] With the continuous development of new energy technology, new energy devices using new energy power generation technology play an increasingly important role in the power system. For example, multiple new energy devices can form a new energy station, which is connected to the power grid through a grid connection point. The new energy device can provide power support to the power grid when the frequency of the grid connection point is unstable. By adjusting the active power of the new energy device, the frequency can be quickly adjusted to restore the frequency of the grid connection point to a stable state.

[0003] However, the current frequency regulation cannot fully utilize the frequency regulation response capabilities of each new energy device, resulting in a slower frequency regulation response speed at new energy sites and a reduction in the overall frequency regulation response capability. Summary of the invention

[0004] The embodiments of the present application provide a frequency regulation method, device, controller and power system for an electric power system, which can improve the overall frequency regulation response capability of the electric power system.

[0005] In a first aspect, an embodiment of the present application provides a frequency regulation method for an electric power system, wherein the electric power system includes a new energy device and an energy storage unit, wherein the energy storage unit is connected to the new energy device, and the new energy device is connected to the power grid through a grid connection point, wherein the method includes: when it is determined that the frequency regulation stage has been entered, based on the frequency regulation parameters and a preset frequency and power droop control characteristic model, obtaining a total active power regulation amount; according to the power regulation capability parameters of the new energy device, the power regulation capability parameters of the energy storage unit, and the power influence parameters of the new energy device, splitting the total active power regulation amount to obtain the active power regulation amount of each new energy device and the active power regulation amount of each energy storage unit, wherein the power influence parameter is positively correlated with the active power regulation amount of the new energy device; controlling each new energy device to operate according to the corresponding active power regulation amount, and controlling each energy storage unit to operate according to the corresponding active power regulation amount, so as to achieve frequency regulation.

[0006] In some possible embodiments, the total active power regulation amount is split according to the power regulation capability parameters of the new energy device, the power regulation capability parameters of the energy storage unit and the power influence parameters of the new energy device, and the active power regulation amount of each new energy device and the active power regulation amount of each energy storage unit are obtained, including: splitting the total active power regulation amount into the new energy active power regulation amount and the energy storage active power regulation amount according to the power regulation capability parameters of the new energy device and the power regulation capability parameters of the energy storage unit; obtaining the weight coefficient corresponding to the power influence parameter, and splitting the new energy active power regulation amount into the active power regulation amount of each new energy device according to the weight coefficient of each new energy device, the weight coefficient being positively correlated with the power influence parameter; and splitting the energy storage active power regulation amount into the active power regulation amount of each energy storage unit according to the power regulation capability parameters of each energy storage unit.

[0007] In some possible embodiments, obtaining a weight coefficient corresponding to a power impact parameter includes: obtaining a preset weight coefficient relationship, the weight coefficient relationship including a corresponding relationship between a power impact parameter interval and a weight coefficient; obtaining in the weight coefficient relationship a weight coefficient corresponding to the power impact parameter interval into which the power impact parameter falls, as the weight coefficient corresponding to the power impact parameter.

[0008] In some possible embodiments, the new energy active power regulation amount is related to a first ratio, and the energy storage active power regulation amount is related to a second ratio. The first ratio includes the ratio of the sum of the power regulation capability parameters of the new energy devices to the first sum, and the second ratio includes the ratio of the sum of the power regulation capability parameters of the energy storage units to the first sum. The first sum is the sum of the sum of the power regulation capability parameters of the new energy devices and the sum of the power regulation capability parameters of the energy storage units.

[0009] In some possible embodiments, the method further includes: when the actual frequency of the grid connection point is lower than the lower limit of the non-frequency modulation frequency range or higher than the upper limit of the non-frequency modulation frequency range, determining to enter the frequency modulation stage, and the non-frequency modulation frequency range is obtained based on the rated frequency and the frequency dead zone; wherein, when the actual frequency of the grid connection point is lower than the lower limit of the non-frequency modulation frequency range, the power regulation capability parameter includes the increaseable power; and when the actual frequency of the grid connection point is higher than the upper limit of the non-frequency modulation frequency range, the power regulation capability parameter includes the reductionable power.

[0010] In some possible embodiments, the method further includes: when it is determined to exit the frequency modulation stage, gradually reducing or increasing the total active power adjustment amount within a preset exit duration until the total active power adjustment amount is zero.

[0011] In some possible embodiments, when it is determined to exit the frequency modulation stage, the total active power regulation amount is gradually reduced or increased within a preset exit duration until the total active power regulation amount is zero, including: when the actual frequency of the grid connection point is within the non-frequency modulation frequency range, determining to exit the frequency modulation stage; within the preset exit duration, superimposing the part of the total active power regulation amount in the target quadrant with the total active power regulation amount over time to obtain the reduced or increased total active power regulation amount, and the reduced or increased total active power regulation amount conforms to a sinusoidal waveform.

[0012] In some possible embodiments, if the total active power adjustment amount is greater than zero, the target quadrant is the third quadrant; if the total active power adjustment amount is less than zero, the target quadrant is the first quadrant.

[0013] In some possible embodiments, the new energy device includes a wind turbine and / or a photovoltaic device; the power influencing parameter includes wind speed and / or light intensity.

[0014] In a second aspect, an embodiment of the present application provides a frequency regulation device for an electric power system, wherein the electric power system includes a new energy device and an energy storage unit, wherein the energy storage unit is connected to the new energy device, and the new energy device is connected to the power grid through a grid connection point, and the frequency regulation device includes: an adjustment amount acquisition module, which is used to obtain the total active power adjustment amount based on the frequency regulation parameters and a preset frequency and power droop control characteristic model when it is determined that the frequency regulation stage has been entered; an adjustment amount allocation module, which is used to split the total active power adjustment amount according to the power regulation capability parameters of the new energy device, the power regulation capability parameters of the energy storage unit and the power influence parameters of the new energy device, and obtain the active power adjustment amount of each new energy device and the active power adjustment amount of each energy storage unit, wherein the power influence parameter is positively correlated with the active power adjustment amount of the new energy device; a control module, which is used to control each new energy device to operate according to the corresponding active power adjustment amount, and to control each energy storage unit to operate according to the corresponding active power adjustment amount, so as to achieve frequency regulation.

[0015] In a third aspect, an embodiment of the present application provides a controller applied to an electric power system, wherein the electric power system includes a new energy device and an energy storage unit, wherein the energy storage unit is connected to the new energy device, and the new energy device is connected to the power grid through a grid connection point; the controller includes: a processor and a memory storing computer program instructions; when the processor executes the computer program instructions, the frequency regulation method of the electric power system of the first aspect is implemented.

[0016] In a fourth aspect, an embodiment of the present application provides an electric power system, comprising: a new energy device, connected to a power grid via a grid connection point; an energy storage unit, connected to the new energy device; and a controller of the third aspect, the controller being used to control the new energy device and the energy storage unit.

[0017] In a fifth aspect, an embodiment of the present application provides a computer-readable storage medium, on which computer program instructions are stored. When the computer program instructions are executed by a processor, the frequency regulation method of the power system of the first aspect is implemented.

[0018] The embodiment of the present application provides a frequency regulation method, device, controller and power system of an electric power system. When entering the frequency regulation stage, the total active power regulation amount of the electric power system is obtained based on the frequency regulation parameters and the frequency and power droop control characteristic model. According to the power regulation capability parameters and power influence parameters of each new energy device, and the power regulation capability parameters of each energy storage unit, the total active power regulation amount is split into the active power regulation amount of each new energy device and the active power regulation amount of each energy storage unit. The power influence parameter is positively correlated with the active power regulation amount of the new energy device, so that the high-power new energy device provides relatively more active power, and the low-power new energy device provides relatively less active power, so as to give full play to the frequency regulation response capability of the new energy device, improve the frequency regulation response speed of the electric power system, and thus improve the overall frequency regulation response capability of the electric power system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solution of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0020] Figure 1 A schematic diagram of the structure of a power system provided in one embodiment of the present application;

[0021] Figure 2 A schematic diagram of the structure of a power system provided in another embodiment of the present application;

[0022] Figure 3 A schematic diagram of the structure of a power system provided in another embodiment of the present application;

[0023] Figure 4 A flow chart of a method for frequency regulation of a power system provided in one embodiment of the present application;

[0024] Figure 5 A schematic diagram of a broken line of an example of a frequency and power droop control characteristic model provided in an embodiment of the present application;

[0025] Figure 6 A flow chart of a method for frequency regulation of a power system provided in another embodiment of the present application;

[0026] Figure 7 A schematic diagram of an example of active power distribution provided in an embodiment of the present application;

[0027] Figure 8 A flow chart of a method for frequency regulation of a power system provided in another embodiment of the present application;

[0028] Fig. 9 A schematic diagram of an example of a change in the total active power regulation amount provided in an embodiment of the present application;

[0029] Fig.10 A schematic diagram of another example of a change in the total active power regulation amount provided in an embodiment of the present application;

[0030] Fig.11 A flowchart of an example of a frequency regulation process of a power system provided in an embodiment of the present application;

[0031] Fig.12 A schematic diagram of the structure of a frequency regulating device for a power system provided in one embodiment of the present application;

[0032] Fig.13 A schematic diagram of the structure of a controller provided in one embodiment of the present application. DETAILED DESCRIPTION

[0033] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, rather than to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present application by illustrating the examples of the present application.

[0034] With the continuous development of new energy technologies, new energy devices using new energy power generation technologies account for an increasingly higher proportion in the power system, and their role is becoming increasingly important. For example, multiple new energy devices can form a new energy station, which is connected to the power grid through a grid connection point. The new energy device can provide power support to the power grid when the frequency of the grid connection point is unstable. By adjusting the active power of the new energy device, the frequency can be quickly adjusted to restore the frequency of the grid connection point to a stable state. However, different new energy devices can provide different frequency modulation response capabilities, and the current frequency modulation is difficult to give full play to the frequency modulation response capabilities of each new energy device, resulting in a slower frequency modulation response speed of the new energy station, reducing the overall frequency modulation response capability. Moreover, when the frequency of the grid connection point is restored to a stable state and exits the frequency modulation process, it is easy to have a frequency reversal phenomenon, that is, a secondary drop or secondary increase in frequency will occur, reducing the stability of the power system.

[0035] The frequency regulation method, device, controller and power system of the power system provided in the present application can obtain the total active power regulation amount of the power system after entering the frequency modulation stage, and distribute the total active power regulation amount to each new energy device and energy storage unit in the power system according to the power influencing parameters of the new energy devices in the power system. The distribution of the total active power regulation amount enables high-power new energy devices to provide relatively more active power, and enables low-power new energy devices to provide relatively less active power, so as to give full play to the frequency modulation response capability of the new energy devices, and improve the frequency modulation response speed of the new energy station where the new energy devices are located, thereby improving the overall frequency modulation response capability of the power system. Moreover, when exiting the frequency modulation stage, the frequency regulation method, device, controller and power system of the power system provided in the present application will gradually adjust the total active power regulation amount, adopt a flexible exit method, avoid the frequency reverse modulation phenomenon, and improve the stability of the power system.

[0036] For ease of understanding, the structure of the power system is first explained here. The power system may include new energy devices and energy storage units. The new energy device is connected to the power grid through a grid connection point, and can provide electric energy to the grid, and can also provide active power for frequency regulation when the frequency of the grid connection point is unstable. The new energy device may include but is not limited to wind turbines, photovoltaic devices, etc. The energy storage unit is connected to the new energy device, and can also provide active power for frequency regulation when the frequency of the grid connection point is unstable. The energy storage unit may include but is not limited to batteries, flywheel devices, etc.

[0037] Figure 1 A schematic diagram of the structure of a power system provided in an embodiment of the present application is shown in FIG. Figure 1 As shown, the new energy device 11 is connected to the power grid 20 via the grid connection point A. The new energy device 11 may include a power generation structure 111 and a converter 112 . The energy storage unit 12 may be connected to the DC bus 13 of the converter 112 .

[0038] Figure 2 A schematic diagram of a power system structure provided in another embodiment of the present application is shown in FIG. Figure 2 As shown, the new energy device 11 is connected to the power grid 20 via the grid connection point A. The new energy device 11 may include a power generation structure 111 and a converter 112. The energy storage unit 12 may be connected to the output end of the converter 112. The above two connection methods of the new energy device 11 and the energy storage unit 12 can both realize a wind, solar and storage integrated power system.

[0039] Figure 3 A schematic diagram of a power system structure provided in another embodiment of the present application is shown in FIG. Figure 3As shown, a plurality of new energy devices 11 can form a new energy station 10, and the plurality of new energy devices 11 can be connected to the grid connection point A through the collection line 14, and connected to the power grid 20 through the grid connection point A. The energy storage unit 12 is connected to the collection line 14. This connection mode of the new energy device 11 and the energy storage unit 12 can realize a power system in which the new energy station 10 and the energy storage unit 12 are independent of each other.

[0040] It should be noted that other connection methods between the new energy device 11 and the energy storage unit 12 are also within the protection scope of the embodiments of the present application.

[0041] The power system may further include a controller, which may execute the frequency regulation method of the power system in the embodiment of the present application, control the new energy device 11 and the energy storage unit 12, and realize frequency regulation.

[0042] The power system may also include other devices, such as a hydrogen production power source or the like, as a power source. The control of other devices may be performed independently and is not limited here.

[0043] The frequency regulation method, device, controller and power system of the power system provided in the present application are described below respectively.

[0044] In a first aspect, the present application provides a frequency regulation method for an electric power system, which can be applied to the electric power system in the above-mentioned embodiment. The frequency regulation method for the electric power system can be executed by a frequency regulation device, a controller, etc. of the electric power system, and will not be described in detail here. Figure 4 A flow chart of a method for adjusting the frequency of a power system provided in an embodiment of the present application, such as Figure 4 As shown, the frequency regulation method of the power system may include steps S301 to S303.

[0045] In step S301, when it is determined that the frequency modulation stage has been entered, the total active power adjustment amount is obtained based on the frequency modulation parameters and a preset frequency and power droop control characteristic model.

[0046] The actual frequency of the grid connection point can be obtained, and whether to enter the frequency modulation stage can be determined based on the actual frequency of the grid connection point. For example, whether to enter the frequency modulation stage can be determined by whether the actual frequency of the grid connection point is in the non-frequency modulation frequency range; if the actual frequency of the grid connection point is in the non-frequency modulation frequency range, it is determined that there is no need to enter the frequency modulation stage; if the actual frequency of the grid connection point exceeds the non-frequency modulation frequency range, it is determined to enter the frequency modulation stage and execute the frequency modulation strategy. The actual frequency of the grid connection point exceeding the non-frequency modulation frequency range may include that the actual frequency is less than the lower limit value of the non-frequency modulation frequency range or that the actual frequency is greater than the upper limit value of the non-frequency modulation frequency range. The non-frequency modulation frequency range is determined based on the rated frequency of the grid connection point and the frequency dead zone. The non-frequency modulation frequency range can be obtained by fluctuating the frequency dead zone with the rated frequency as the center. The frequency dead zone can be set according to the scenario, demand, experience, etc., and is not limited here; for example, in a frequency modulation, the frequency dead zone of the wind farm can be in the range of ±0.03Hz to ±0.1Hz, which can be specifically set according to the grid demand; for another example, in a frequency modulation, the frequency dead zone of the photovoltaic power station can be in the range of ±0.02Hz to ±0.06Hz, which can be specifically set according to the grid demand. In some examples, the actual frequency of the grid-connected point can be compared with the lower limit value and the upper limit value of the non-frequency modulation frequency range to determine whether the actual frequency of the grid-connected point exceeds the non-frequency modulation frequency range, that is, to determine whether to enter the frequency modulation stage. When the actual frequency of the grid-connected point is lower than the lower limit value of the non-frequency modulation frequency range or higher than the upper limit value of the non-frequency modulation frequency range, it is determined to enter the frequency modulation stage. The frequency modulation flag can be configured to indicate whether to enter the frequency modulation stage. In the case of determining to enter the frequency modulation stage, the frequency modulation flag can be set to the first flag; in the case of determining not to enter the frequency modulation stage or exit the frequency modulation stage, the frequency modulation flag can be set to the second flag. The first flag is different from the second flag.

[0047] The frequency modulation parameters may include frequency-related parameters required for frequency modulation. In some examples, the frequency modulation parameters may include, but are not limited to, one or more of the frequency dead zone, the actual frequency of the grid connection point, the rated frequency of the grid connection point, the rated power of the new energy station where the new energy device is located, the active frequency modulation coefficient of the new energy station where the new energy device is located, and the initial value of the active power of the new energy station where the new energy device is located. Among them, the initial value of the active power of the new energy station may be the actual active power at the moment of entering the frequency modulation stage. The frequency and power droop control characteristic model can characterize the relationship between the frequency of the grid connection point of the power system and the active power to which the new energy station should be adjusted. The frequency and power droop control characteristic model can be used to perform power and power droop control. The frequency and power droop control characteristic model can be obtained based on the frequency modulation parameters and the droop control principle. For example, Figure 5A schematic diagram of an example of a frequency and power droop control characteristic model provided in an embodiment of the present application, wherein the rated frequency may be 50 Hz, the frequency dead zone may be ±0.1 Hz (other values ​​may also be taken, which are not limited here), the non-frequency modulation frequency range is [49.9 Hz, 50.1 Hz], P n is the rated power of the new energy station, such as Figure 5 As shown, the frequency conditions in the non-frequency modulation frequency range do not participate in the frequency modulation. The power corresponding to the frequency outside the non-frequency modulation frequency range has changed compared to the power corresponding to the frequency in the non-frequency modulation frequency range. In the frequency modulation process, it is expected to obtain the total active power regulation according to the frequency and power droop control characteristic model, and also the active power of the power system. The total active power regulation is the total amount of active power required to regulate the power system for frequency modulation. The frequency and power droop control characteristic model can be obtained by the following equations (1) and (2):

[0048] P Set =P0+ΔP (1)

[0049]

[0050] Among them, P Set is the active power setting value of the power system; P0 is the initial value of active power before the power system frequency regulation; ΔP is the total active power regulation; P t is the rated power or real-time power of the power system, which can be configured on site; Δf is the frequency deviation of the power system, which can be specifically the difference between the actual frequency of the grid connection point and the upper limit of the non-frequency modulation frequency range when the actual frequency exceeds the non-frequency modulation frequency range, or the difference between the grid connection point and the lower limit of the non-frequency modulation frequency range; f n is the rated frequency of the grid connection point; K f is the active frequency modulation coefficient.

[0051] In step S302, the total active power regulation amount is split according to the power regulation capability parameters of the new energy device, the power regulation capability parameters of the energy storage unit and the power impact parameters of the new energy device, and the active power regulation amount of each new energy device and the active power regulation amount of each energy storage unit are obtained.

[0052] The power regulation capability parameter of a new energy device may characterize the amount of active power that the new energy device can regulate. In some examples, the power regulation capability parameter of the new energy device may include the increaseable power and the decreaseable power of the new energy device. The increaseable power of the new energy device may be obtained according to the difference between the theoretical active power of the new energy device and the actual active power of the new energy device, and the decreaseable power of the new energy device may be obtained according to the lower limit of the active power of the new energy device. The power regulation capability parameters of different new energy devices may be the same or different. The power regulation capability parameter of the energy storage unit may characterize the amount of active power that the energy storage unit can regulate. In some examples, the power regulation capability parameter of the energy storage unit may include the increaseable power and the decreaseable power of the energy storage unit. The increaseable power of the energy storage unit may be obtained according to the upper limit of the state of charge (SOC) of the energy storage unit; the decreaseable power of the energy storage unit may be obtained according to the lower limit of the state of charge of the energy storage unit. The power influencing parameters of the new energy device may include parameters that can affect the output of the new energy device, that is, parameters that can affect the active power of the new energy device. For example, the new energy device includes a wind turbine, and the power influencing parameters of the wind turbine may include wind speed; the new energy device includes a photovoltaic device, and the power influencing parameters of the photovoltaic device may include light intensity.

[0053] The total active power regulation amount can be divided into multiple active power regulation amounts to be allocated to each new energy device and each energy storage unit. The active power regulation amount of the new energy device is the active power regulation amount added on the basis of the active power of the new energy device. The active power regulation amount of the energy storage unit is the active power regulation amount added on the basis of the active power of the energy storage unit. The total active power regulation amount can be a positive value or a negative value, and the active power regulation amount is a positive value or a negative value accordingly. The power influence parameter of the new energy device is positively correlated with the active power regulation amount of the new energy device. The larger the power influence parameter of the new energy device, the higher the active power that can participate in frequency modulation, and correspondingly, the higher the active power regulation amount of the new energy device; similarly, the smaller the power influence parameter of the new energy device, the lower the active power that can participate in frequency modulation, and correspondingly, the lower the active power regulation amount of the new energy device. For example, for wind turbines, the greater the wind speed, the higher the active power of the wind turbine, and a higher active power adjustment amount should be allocated to wind turbines with higher wind speeds; the lower the wind speed, the lower the active power of the wind turbine, and a lower active power adjustment amount should be allocated to wind turbines with lower wind speeds. For another example, for photovoltaic devices, the greater the light intensity, the higher the active power of the photovoltaic device, and a higher active power adjustment amount should be allocated to photovoltaic devices with greater light intensity; the lower the light intensity, the lower the active power of the photovoltaic device, and a lower active power adjustment amount should be allocated to wind turbines with lower light intensity.

[0054] In step S303, each new energy device is controlled to operate according to the corresponding active power adjustment amount, and each energy storage unit is controlled to operate according to the corresponding active power adjustment amount to achieve frequency regulation.

[0055] Each new energy device is controlled to adjust its own active power according to its corresponding active power adjustment amount, and operate according to the adjusted active power. Also, each energy storage unit is controlled to adjust its own active power according to its corresponding active power adjustment amount, and operate according to the adjusted active power. The new energy device and the energy storage unit achieve frequency regulation by adjusting the active power according to the active power adjustment amount, so as to pull the frequency of the grid connection point back to the non-frequency modulation frequency range, that is, to ensure the stability of the frequency of the grid connection point.

[0056] In an embodiment of the present application, when entering the frequency modulation stage, based on the frequency modulation parameters and the frequency and power droop control characteristic model, the total active power regulation amount of the power system is obtained, and according to the power regulation capability parameters and power influence parameters of each new energy device, as well as the power regulation capability parameters of each energy storage unit, the total active power regulation amount is split into the active power regulation amount of each new energy device and the active power regulation amount of each energy storage unit. The power influence parameter is positively correlated with the active power regulation amount of the new energy device, so that the high-power new energy device provides relatively more active power, and the low-power new energy device provides relatively less active power, so as to give full play to the frequency modulation response capability of the new energy device, improve the frequency modulation response speed of the power system, and thus improve the overall frequency modulation response capability of the power system.

[0057] In some embodiments, the total active power regulation amount can be first split into the total regulation amount for use by all new energy devices, i.e., the new energy active power regulation amount, and the total regulation amount for use by all energy storage units, i.e., the energy storage active power regulation amount, and then the new energy active power regulation amount and the energy storage active power regulation amount can be split separately to obtain the active power regulation amount of each new energy device and the active power regulation amount of each energy storage unit.

[0058] Figure 6 This is a flow chart of a method for frequency regulation of a power system provided in another embodiment of the present application. Figure 6 and Figure 4 The difference is that Figure 4 Step S302 in the method can be specifically divided into steps S3021 to S3023.

[0059] In step S3021, the total active power regulation amount is split into the new energy active power regulation amount and the energy storage active power regulation amount according to the power regulation capability parameters of the new energy device and the power regulation capability parameters of the energy storage unit.

[0060] According to the power regulation capability parameters of the new energy device and the power regulation capability parameters of the energy storage unit, the total regulation amount corresponding to the regulation capability of all new energy devices and the total regulation amount corresponding to the regulation capability of all energy storage units can be determined. The new energy active power regulation amount can be the total regulation amount corresponding to the regulation capability of all new energy devices. The energy storage active power regulation amount can be the total regulation amount corresponding to the regulation capability of all energy storage units.

[0061] In some examples, the active power adjustment amount of new energy and the active power adjustment amount of energy storage can be obtained by splitting according to the proportion of the power adjustment capability parameter of the new energy device and the power adjustment capability parameter of the energy storage unit. The active power adjustment amount of new energy is related to the first proportion, and the active power adjustment amount of energy storage is related to the second proportion. The first proportion includes the proportion of the sum of the power adjustment capability parameters of the new energy device to the first sum, and the second proportion includes the proportion of the sum of the power adjustment capability parameters of the energy storage unit to the first sum, and the first sum is the sum of the sum of the power adjustment capability parameters of the new energy device and the sum of the power adjustment capability parameters of the energy storage unit. There are two situations in which the actual frequency of the grid connection point exceeds the non-frequency modulation frequency range, one is that the actual frequency is lower than the lower limit of the non-frequency modulation frequency range, and the other is that the actual frequency is higher than the upper limit of the non-frequency modulation frequency range. In the case where the actual frequency of the grid connection point is lower than the lower limit of the non-frequency modulation frequency range, the power adjustment capability parameter may include the power that can be increased; in the case where the actual frequency of the grid connection point is higher than the upper limit of the non-frequency modulation frequency range, the power adjustment capability parameter may include the power that can be reduced. For example, taking the power system as a wind-storage system, that is, the power system includes a wind turbine and an energy storage unit, the new energy active power adjustment amount and the energy storage active power adjustment amount can be obtained according to the following equations (3) to (8):

[0062]

[0063] Among them, ΔP WF is the active power regulation of new energy; ΔP ESS is the energy storage active power regulation; ΔP is the total active power regulation; Δf=ff d , Δf<0 means that the actual frequency of the grid-connected point is less than the lower limit of the non-frequency modulation frequency range, and Δf>0 means that the actual frequency of the grid-connected point is greater than the upper limit of the non-frequency modulation frequency range; P upWT (i) is the increaseable power of the i-th new energy device; P upWF is the sum of the power that can be increased by n new energy devices; P upES (i) is the increaseable power of the i-th energy storage unit; P upESS is the sum of the increaseable power of m energy storage units; P downWT (i) is the reducible power of the i-th new energy device; P downWF is the sum of the power reduction of n new energy devices; P downES(i) is the reducible power of the i-th energy storage unit; P downESS is the sum of the reducible powers of m energy storage units.

[0064] In step S3022, a weight coefficient corresponding to the power influencing parameter is obtained, and the new energy active power adjustment amount is split into the active power adjustment amount of each new energy device according to the weight coefficient of each new energy device.

[0065] The weight coefficient has a corresponding relationship with the power influencing parameter, in which the weight coefficient is positively correlated with the power influencing parameter. The larger the power influencing parameter, the larger the weight coefficient; the smaller the power influencing parameter, the smaller the weight coefficient. For example, the power influencing parameters of the new energy device include wind speed, and a weight coefficient that increases with increasing wind speed can be pre-set; the power influencing parameters of the new energy device include light intensity, and a weight coefficient that increases with increasing light intensity can be pre-set. The weight coefficient can be used to calculate the active power regulation amount of each new energy device. The weight coefficient is positively correlated with the active power regulation amount of the new energy device. The larger the weight coefficient, the larger the active power regulation amount of the new energy device. For example, the active power regulation amount of the new energy device can be obtained according to the following formula (9):

[0066]

[0067] Among them, ΔP WT (i) is the active power regulation of the i-th new energy device; ΔP WF is the active power regulation of new energy; W(v i ) is the power influencing parameter v i The corresponding weight coefficient; N(v i ) is the power influencing parameter v i The number of new energy devices.

[0068] In some examples, a weight coefficient relationship may be preset, and the weight coefficient relationship includes a corresponding relationship between a power impact parameter interval and a weight coefficient. For example, if the power impact parameter includes wind speed, the weight coefficient relationship may be as shown in Table 1 below:

[0069] Table 1

[0070] Wind speed (m / s) Weight coefficient v≤6 1 <![CDATA[6 ＜ v≤7]]> 2 <![CDATA[7 ＜ v≤8]]> 3 <![CDATA[8 ＜ v≤9]]> 4 <![CDATA[9 ＜ v≤10]]> 5 <![CDATA[10 ＜ v≤11]]> 9 <![CDATA[11 ＜ v≤12]]> 10 <![CDATA[12 ＜ v≤13]]> 11 <![CDATA[13 ＜ v≤14]]> 12 <![CDATA[v ＞ 14]]> 13

[0071] A weight coefficient relationship may be obtained, and a weight coefficient corresponding to the power influence parameter interval into which the power influence parameter falls may be obtained in the weight coefficient relationship as the weight coefficient corresponding to the power influence parameter. For example, as shown in Table 1, if the wind speed of the wind turbine is 10 m / s, the weight coefficient corresponding to the wind speed is 5.

[0072] In step S3023, the energy storage active power adjustment amount is split into the active power adjustment amount of each energy storage unit according to the power adjustment capability parameter of each energy storage unit.

[0073] The active power regulation amount of each energy storage unit can be obtained by splitting the energy storage active power regulation amount according to the ratio of the power regulation capability parameter of each energy storage unit to the sum of the power regulation capability parameters of all energy storage units. For example, the active power regulation amount of the energy storage unit can be obtained according to the following formula (10):

[0074]

[0075] Among them, ΔP ES (i) is the active power adjustment value of the i-th energy storage unit; the definitions of other parameters can refer to the definitions in the above embodiments and will not be repeated here.

[0076] Figure 7 A schematic diagram of an example of active power distribution provided in an embodiment of the present application is shown as follows: Figure 7 As shown, the rated frequency f of the grid connection point can be n The difference between the actual frequency f of the grid connection point is controlled to droop in order to obtain the total active power regulation amount. The total active power regulation amount is first allocated to the new energy active power regulation amount and the energy storage active power regulation amount. The new energy active power regulation amount can be allocated to the active power regulation amount of the new energy device required for each new energy device to perform single-machine frequency regulation. The energy storage active power regulation amount can be allocated to the active power regulation amount of the energy storage unit required for each energy storage unit to perform energy storage unit frequency regulation. In some examples, the active power regulation amount of the new energy device and the active power regulation amount of the energy storage device can be limited (i.e. Figure 7 max and min in ).

[0077] When the frequency of the grid connection point is disturbed, the total active power regulation will be suppressed. If the active power regulation is directly set to 0 after the frequency of the grid connection point returns to normal, it is very likely to cause a secondary fluctuation in the frequency of the grid connection point. The embodiment of the present application will use a flexible exit method to exit the frequency modulation stage. Figure 8 A flow chart of a method for frequency regulation of a power system provided in another embodiment of the present application, Figure 8 and Figure 4 The difference is that Figure 8 The frequency regulation method of the power system shown may further include step S304.

[0078] In step S304, when it is determined to exit the frequency modulation stage, the total active power adjustment amount is gradually reduced or increased within a preset exit time until the total active power adjustment amount is zero.

[0079] Whether to exit the frequency modulation stage can be determined based on whether the actual frequency of the grid connection point is within the non-frequency modulation frequency range. If the actual frequency of the grid connection point is within the non-frequency modulation frequency range, it is determined to exit the frequency modulation stage. If the actual frequency of the grid connection point is within the non-frequency modulation frequency range, it can be determined that the frequency of the grid connection point has returned to normal, thereby determining to exit the frequency modulation stage.

[0080] The preset exit duration can be set according to the scenario, demand, experience, etc., and is not limited here. If the total active power adjustment amount is greater than zero during the frequency modulation stage, the total active power adjustment amount is gradually reduced within the preset exit duration until the total active power adjustment amount is zero. If the total active power adjustment amount is less than zero during the frequency modulation stage, the total active power adjustment amount is gradually increased within the preset exit duration until the total active power adjustment amount is zero. In some examples, within the preset exit duration, the portion of the total active power adjustment amount in the target quadrant is superimposed with the total active power adjustment amount over time to obtain the reduced or increased total active power adjustment amount, and the reduced or increased total active power adjustment amount conforms to a sinusoidal waveform. If the total active power adjustment amount is greater than zero, the target quadrant is the third quadrant, and the part of the total active power adjustment amount in the third quadrant is a negative value, the part of the total active power adjustment amount in the third quadrant is superimposed on the total active power adjustment amount to obtain the reduced total active power adjustment amount, and the total active power adjustment amount is gradually reduced over time by superimposing the part of the total active power adjustment amount in the third quadrant, and the waveform of the total active power adjustment amount after the reduction within the preset exit time length changes with time conforms to a sine waveform. Similarly, if the total active power adjustment amount is less than zero, the target quadrant is the first quadrant, and the part of the total active power adjustment amount in the first quadrant is a positive value, the part of the total active power adjustment amount in the first quadrant is superimposed on the total active power adjustment amount to obtain the increased total active power adjustment amount, and the total active power adjustment amount is gradually reduced over time by superimposing the part of the total active power adjustment amount in the first quadrant, and the waveform of the total active power adjustment amount after the increase within the preset exit time length changes with time conforms to a sine waveform. During the preset exit time, the total active power regulation amount after reduction or increase will be split according to the power regulation capability parameters of the new energy device, the power regulation capability parameters of the energy storage unit and the power impact parameters of the new energy device, and the active power regulation amount of each new energy device and the active power regulation amount of each energy storage unit will be obtained. Each new energy device will be controlled to operate according to the corresponding active power regulation amount, and each energy storage unit will be controlled to operate according to the corresponding active power regulation amount, so as to realize flexible exit of frequency modulation.

[0081] For example, the adjustment of the total active power adjustment amount can be obtained according to the following equations (11) and (12). The following equation (11) is valid when the total active power adjustment amount is greater than 0, and the following equation (12) is valid when the total active power adjustment amount is less than 0:

[0082]

[0083] Among them, ΔP′ is the total active power regulation after reduction or increase; ΔP is the total active power regulation before reduction or increase; t is the current time; T0 is the time to determine the exit from the frequency modulation stage; T is the preset exit duration.

[0084] Fig. 9 A schematic diagram of an example of a change in the total active power regulation amount provided in an embodiment of the present application, Fig.10 A schematic diagram of another example of a change in the total active power regulation amount provided in an embodiment of the present application, Fig. 9 and Fig.10 The horizontal axis represents time, and the vertical axis represents the total active power regulation. Fig. 9 The figure shows the change of the total active power regulation amount when the total active power regulation amount is greater than zero. If the direct exit method is adopted, the total active power regulation amount will be directly adjusted to zero at time T0, which is very likely to cause a secondary disturbance of the frequency of the grid connection point; if the flexible exit method in the embodiment of the present application is adopted, starting from time T0, the part of the total active power regulation amount in the third quadrant will be superimposed with the total active power regulation amount over time to obtain the total active power regulation amount after the reduction within the preset exit time from time T0 to time T0+T, such as Fig. 9 As shown, the total active power regulation amount after reduction within the preset exit time from time T0 to time T0+T conforms to a sinusoidal waveform. This flexible exit method of gradually reducing the total active power regulation amount can avoid secondary fluctuations in the frequency of the grid connection point to ensure the stability of the power system. Fig.10 The figure shows the change of the total active power regulation amount when the total active power regulation amount is less than zero. If the direct exit method is adopted, the total active power regulation amount will be directly adjusted to zero at time T0, so it is very likely that a secondary fluctuation of the frequency of the grid connection point will occur; if the flexible exit method in the embodiment of the present application is adopted, starting from time T0, the part of the total active power regulation amount in the first quadrant will be superimposed with the total active power regulation amount over time to obtain the total active power regulation amount increased within the preset exit time from time T0 to time T0+T, such as Fig.10 As shown, the total active power regulation amount increased within the preset exit time from time T0 to time T0+T conforms to a sinusoidal waveform. This flexible exit method of gradually increasing the total active power regulation amount can avoid secondary fluctuations in the frequency of the grid connection point to ensure the stability of the power system.

[0085] To facilitate understanding, the frequency regulation process of the power system in the embodiment of the present application is described below. Fig.11 A flowchart of an example of a frequency regulation process of a power system provided in an embodiment of the present application, such as Fig.11 As shown, the frequency regulation process of the power system may include steps a1 to a10.

[0086] In step a1, the actual frequency of the grid connection point is obtained.

[0087] In step a2, determine whether the actual frequency exceeds the non-frequency modulation frequency range. If it exceeds the non-frequency modulation frequency range, it indicates entering the frequency modulation stage, and step a3 is executed; if it does not exceed the non-frequency modulation frequency range, it indicates not entering the frequency modulation stage and operating normally or exiting the frequency modulation stage, and step a9 is executed. It should be noted that when the actual frequency exceeds the non-frequency modulation frequency range, the frequency modulation mark position can be set to the first mark; when the actual frequency does not exceed the non-frequency modulation frequency range, the frequency modulation mark position can be set to the second mark.

[0088] In step a3, the total active power adjustment amount is obtained by droop control calculation, which can be obtained by frequency modulation parameters and a preset frequency and power droop control characteristic model.

[0089] In step a4, the total active power regulation amount is allocated to obtain the new energy active power regulation amount and the energy storage active power regulation amount.

[0090] In step a5, the new energy active power adjustment amount is allocated to obtain the active power adjustment amount of each new energy device.

[0091] In step a6, the energy storage active power adjustment amount is allocated to obtain the active power adjustment amount of each energy storage unit.

[0092] In step a7, the new energy device is controlled to perform the corresponding active power adjustment amount, and then returns to step a2.

[0093] In step a8, the energy storage unit is controlled to perform the corresponding active power adjustment amount, and then returns to step a2.

[0094] In step a9, it is determined whether the frequency modulation identification bit at the previous moment is the same as the frequency modulation identification bit at the current moment. If they are the same, the process ends; if they are not the same, step a10 is executed.

[0095] In step a10, a flexible exit strategy is executed. The flexible exit strategy can be seen in the relevant description of the flexible exit in the above embodiment, which will not be repeated here.

[0096] The specific contents of the above steps a1 to a10 can be found in the relevant descriptions in the above embodiments, which will not be repeated here.

[0097] A second aspect of the present application provides a frequency regulating device for an electric power system. The specific contents of the electric power system can be found in the relevant contents in the above embodiments and will not be repeated here. Fig.12 A schematic diagram of the structure of a frequency regulating device for a power system provided in an embodiment of the present application is shown in FIG. Fig.12As shown, the frequency regulation device 400 of the power system may include a regulation amount acquisition module 401 , a regulation amount allocation module 402 and a control module 403 .

[0098] The adjustment amount acquisition module 401 can be used to obtain the total active power adjustment amount based on the frequency modulation parameters and the preset frequency and power droop control characteristic model when it is determined that the frequency modulation stage has been entered.

[0099] The regulation amount allocation module 402 can be used to split the total active power regulation amount according to the power regulation capability parameters of the new energy device, the power regulation capability parameters of the energy storage unit and the power impact parameters of the new energy device, and obtain the active power regulation amount of each new energy device and the active power regulation amount of each energy storage unit.

[0100] Among them, the power influencing parameters are positively correlated with the active power regulation of the new energy device.

[0101] The control module 403 can be used to control each new energy device to operate according to the corresponding active power adjustment amount, and control each energy storage unit to operate according to the corresponding active power adjustment amount to achieve frequency regulation.

[0102] In some embodiments, the regulation amount allocation module 402 can be specifically used to: split the total active power regulation amount into the new energy active power regulation amount and the energy storage active power regulation amount according to the power regulation capability parameters of the new energy device and the power regulation capability parameters of the energy storage unit; obtain the weight coefficient corresponding to the power influencing parameter, and split the new energy active power regulation amount into the active power regulation amount of each new energy device according to the weight coefficient of each new energy device, and the weight coefficient is positively correlated with the power influencing parameter; split the energy storage active power regulation amount into the active power regulation amount of each energy storage unit according to the power regulation capability parameters of each energy storage unit.

[0103] In some examples, the adjustment amount allocation module 402 can be specifically used to: obtain a preset weight coefficient relationship, the weight coefficient relationship including a corresponding relationship between a power impact parameter interval and a weight coefficient; obtain the weight coefficient corresponding to the power impact parameter interval into which the power impact parameter falls in the weight coefficient relationship, as the weight coefficient corresponding to the power impact parameter.

[0104] In some examples, the new energy active power regulation amount is related to a first ratio, and the energy storage active power regulation amount is related to a second ratio. The first ratio includes the ratio of the sum of the power regulation capability parameters of the new energy device to the first sum. The second ratio includes the ratio of the sum of the power regulation capability parameters of the energy storage unit to the first sum. The first sum is the sum of the sum of the power regulation capability parameters of the new energy device and the sum of the power regulation capability parameters of the energy storage unit.

[0105] In some embodiments, the frequency regulation device 400 of the power system may further include a dead zone judgment module. The dead zone judgment module may be used to determine that the frequency regulation stage has been entered when the actual frequency of the grid-connected point is lower than the lower limit of the non-frequency modulation frequency range or higher than the upper limit of the non-frequency modulation frequency range. The non-frequency modulation frequency range is obtained based on the rated frequency and the frequency dead zone. Among them, when the actual frequency of the grid-connected point is lower than the lower limit of the non-frequency modulation frequency range, the power regulation capability parameter includes the power that can be increased; when the actual frequency of the grid-connected point is higher than the upper limit of the non-frequency modulation frequency range, the power regulation capability parameter includes the power that can be reduced.

[0106] In some embodiments, the frequency regulation device 400 of the power system may further include a flexible exit execution module. The flexible exit execution module may be used to: when it is determined to exit the frequency regulation stage, gradually reduce or increase the total active power regulation amount within a preset exit duration until the total active power regulation amount is zero.

[0107] In some examples, the flexible exit execution module can be specifically used to: determine the exit from the frequency modulation stage when the actual frequency of the grid connection point is within the non-frequency modulation frequency range; within the preset exit duration, superimpose the portion of the total active power regulation amount in the target quadrant with the total active power regulation amount over time to obtain the reduced or increased total active power regulation amount, and the reduced or increased total active power regulation amount conforms to a sinusoidal waveform.

[0108] In some examples, if the total active power regulation amount is greater than zero, the target quadrant is the third quadrant. If the total active power regulation amount is less than zero, the target quadrant is the first quadrant.

[0109] In some embodiments, the new energy device includes a wind turbine and / or a photovoltaic device. The power influencing parameter includes wind speed and / or light intensity.

[0110] It should be noted that the frequency regulation device 400 of the power system is a device corresponding to the frequency regulation method of the power system mentioned above, and all implementation methods in the above method embodiments are applicable to the embodiments of the device and can achieve the same technical effects.

[0111] The third aspect of the present application also provides a controller that can be applied to the power system in the above embodiment. Fig.13 A schematic diagram of the structure of a controller provided in an embodiment of the present application is shown in FIG. Fig.13 As shown, the controller 500 includes a memory 501 , a processor 502 , and a computer program stored in the memory 501 and executable on the processor 502 .

[0112] In some examples, the processor 502 may include a central processing unit (CPU), or an application specific integrated circuit (ASIC), or may be configured to implement one or more integrated circuits of the embodiments of the present application.

[0113] The memory 501 may include a read-only memory (ROM), a random access memory (RAM), a disk storage medium device, an optical storage medium device, a flash memory device, an electrical, optical or other physical / tangible memory storage device. Therefore, generally, the memory includes one or more tangible (non-transitory) computer-readable storage media (e.g., a memory device) encoded with software including computer executable instructions, and when the software is executed (e.g., by one or more processors), it is operable to perform the operations described with reference to the frequency regulation method of the power system according to the embodiment of the present application.

[0114] The processor 502 runs a computer program corresponding to the executable program code by reading the executable program code stored in the memory 501 , so as to implement the frequency regulation method of the power system in the above embodiment.

[0115] In some examples, the controller 500 may further include a communication interface 503 and a bus 504. Fig.13 As shown, the memory 501, the processor 502, and the communication interface 503 are connected via a bus 504 and communicate with each other.

[0116] The communication interface 503 is mainly used to realize the communication between the modules, devices, units and / or equipment in the embodiment of the present application. The communication interface 503 can also be used to access input devices and / or output devices.

[0117] The bus 504 includes hardware, software, or both, coupling the components of the controller 500 to each other. By way of example and not limitation, the bus 504 may include an Accelerated Graphics Port (AGP) or other graphics bus, an Enhanced Industry Standard Architecture (EISA) bus, a Front Side Bus (FSB), a Hyper Transport (HT) interconnect, an Industry Standard Architecture (ISA) bus, an InfiniBand interconnect, a Low Pin Count (LPC) bus, a Memory bus, a Micro Channel Architecture (MCA) bus, a Peripheral Component Interconnect (PCI) bus, a PCI-Express (PCI-E) bus, a Serial Advanced Technology Attachment (SATA) bus, a Video Electronics Standards Association Local Bus (VLB) bus, or other suitable buses or a combination of two or more of the above. Where appropriate, the bus 504 may include one or more buses. Although embodiments of the present application describe and illustrate a particular bus, the present application contemplates any suitable bus or interconnect.

[0118] The fourth aspect of the present application provides an electric power system. The electric power system includes a new energy device, an energy storage unit and the controller in the above-mentioned embodiment. The new energy device is connected to the power grid through a grid connection point. The energy storage unit is connected to the new energy device. The controller can be used to execute the frequency regulation method of the electric power system in the above-mentioned embodiment to control the new energy device and the energy storage unit. For specific contents, please refer to the relevant descriptions in the above-mentioned embodiments, and the same technical effects can be achieved. In order to avoid repetition, they will not be repeated here.

[0119] In a fifth aspect of the present application, a computer-readable storage medium is provided, on which a computer program instruction is stored, and when the computer program instruction is executed by a processor, the frequency regulation method of the power system in the above-mentioned embodiment can be implemented, and the same technical effect can be achieved. To avoid repetition, it is not repeated here. Among them, the above-mentioned computer-readable storage medium may include a non-transitory computer-readable storage medium, such as a read-only memory (Read-Only Memory, referred to as ROM), a random access memory (Random Access Memory, referred to as RAM), a disk or an optical disk, etc., which is not limited here.

[0120] An embodiment of the present application provides a computer program product, which includes a computer program. When the computer program is executed by a processor, it implements the frequency regulation method of the power system in the above embodiment and can achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0121] It should be clear that the various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. For device embodiments, controller embodiments, power system embodiments, and computer-readable storage medium embodiments, the relevant parts can refer to the description part of the method embodiment. The present application is not limited to the specific steps and structures described above and shown in the figures. Those skilled in the art can make various changes, modifications and additions, or change the order between the steps after understanding the spirit of the present application. In addition, for the sake of brevity, a detailed description of known method technologies is omitted here.

[0122] The above reference is according to the method of the embodiment of the present application, the flow chart of the device (system) and the computer program product and / or the block diagram described various aspects of the present application.It should be understood that each square box in the flow chart and / or the block diagram and the combination of each square box in the flow chart and / or the block diagram can be realized by computer program instructions.These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer or other programmable data processing device to produce a machine so that these instructions executed by the processor of the computer or other programmable data processing device enable the realization of the function / action specified in one or more square boxes of the flow chart and / or the block diagram.Such a processor can be but is not limited to a general-purpose processor, a special-purpose processor, a special application processor or a field programmable logic circuit.It can also be understood that each square box in the block diagram and / or the flow chart and the combination of the square boxes in the block diagram and / or the flow chart can also be realized by the dedicated hardware that performs the specified function or action, or can be realized by the combination of dedicated hardware and computer instructions.

[0123] Those skilled in the art should understand that the above embodiments are exemplary rather than restrictive. Different technical features appearing in different embodiments can be combined to achieve beneficial effects. Based on the study of the drawings, the specification and the claims, those skilled in the art should be able to understand and implement other variations of the disclosed embodiments. In the claims, the term "comprising" does not exclude other devices or steps; the quantifier "one" does not exclude multiple; the terms "first" and "second" are used to indicate names rather than to indicate any specific order. Any figure marks in the claims should not be understood as limiting the scope of protection. The functions of multiple parts appearing in the claims can be implemented by a single hardware or software module. The appearance of certain technical features in different dependent claims does not mean that these technical features cannot be combined to achieve beneficial effects.

Claims

1. A method for frequency regulation of a power system, characterized in that: The power system includes a new energy device and an energy storage unit, the energy storage unit is connected to the new energy device, and the new energy device is connected to the power grid through a grid connection point. The method includes: When it is determined that the frequency modulation stage has been entered, the total active power regulation amount is obtained based on the frequency modulation parameters and the preset frequency and power droop control characteristic model; According to the power regulation capability parameter of the new energy device, the power regulation capability parameter of the energy storage unit and the power influence parameter of the new energy device, the total active power regulation amount is split to obtain the active power regulation amount of each new energy device and the active power regulation amount of each energy storage unit, wherein the power influence parameter is positively correlated with the active power regulation amount of the new energy device; Each of the new energy devices is controlled to operate according to the corresponding active power adjustment amount, and each of the energy storage units is controlled to operate according to the corresponding active power adjustment amount to achieve frequency regulation.

2. The method according to claim 1, characterized in that The method of splitting the total active power adjustment amount according to the power adjustment capability parameter of the new energy device, the power adjustment capability parameter of the energy storage unit and the power influence parameter of the new energy device, and obtaining the active power adjustment amount of each new energy device and the active power adjustment amount of each energy storage unit includes: According to the power regulation capability parameter of the new energy device and the power regulation capability parameter of the energy storage unit, the total active power regulation amount is split into the new energy active power regulation amount and the energy storage active power regulation amount; Obtaining a weight coefficient corresponding to the power influencing parameter, and splitting the new energy active power adjustment amount into the active power adjustment amount of each new energy device according to the weight coefficient of each new energy device, wherein the weight coefficient is positively correlated with the power influencing parameter; According to the power regulation capability parameter of each energy storage unit, the energy storage active power regulation amount is split into the active power regulation amount of each energy storage unit.

3. The method according to claim 2, characterized in that The obtaining of the weight coefficient corresponding to the power impact parameter includes: Obtaining a preset weight coefficient relationship, wherein the weight coefficient relationship includes a corresponding relationship between a power impact parameter interval and the weight coefficient; The weight coefficient corresponding to the power impact parameter interval into which the power impact parameter falls is obtained in the weight coefficient relationship as the weight coefficient corresponding to the power impact parameter.

4. The method according to claim 2, characterized in that: The new energy active power regulation amount is related to a first ratio, and the energy storage active power regulation amount is related to a second ratio. The first ratio includes the ratio of the sum of the power regulation capability parameters of the new energy device to the first sum, and the second ratio includes the ratio of the sum of the power regulation capability parameters of the energy storage unit to the first sum. The first sum is the sum of the sum of the power regulation capability parameters of the new energy device and the sum of the power regulation capability parameters of the energy storage unit.

5. The method according to claim 1, characterized in that Also includes: When the actual frequency of the grid connection point is lower than the lower limit of the non-frequency modulation frequency range or higher than the upper limit of the non-frequency modulation frequency range, it is determined to enter the frequency modulation stage, and the non-frequency modulation frequency range is obtained based on the rated frequency and the frequency dead zone; Among them, when the actual frequency of the grid connection point is lower than the lower limit of the non-frequency modulation frequency range, the power regulation capability parameter includes the increaseable power; when the actual frequency of the grid connection point is higher than the upper limit of the non-frequency modulation frequency range, the power regulation capability parameter includes the reductionable power.

6. The method according to claim 1, characterized in that Also includes: When it is determined to exit the frequency modulation stage, the total active power adjustment amount is gradually reduced or increased within a preset exit duration until the total active power adjustment amount is zero.

7. The method according to claim 6, characterized in that In the case of determining to exit the frequency modulation stage, gradually reducing or increasing the total active power adjustment amount within a preset exit time until the total active power adjustment amount is zero, including: When the actual frequency of the grid connection point is within the non-frequency modulation frequency range, determining to exit the frequency modulation stage; Within the preset exit time, the part of the total active power adjustment amount in the target quadrant is superimposed on the total active power adjustment amount over time to obtain the reduced or increased total active power adjustment amount, and the reduced or increased total active power adjustment amount conforms to a sinusoidal waveform.

8. The method according to claim 7, characterized in that If the total active power adjustment amount is greater than zero, the target quadrant is the third quadrant; If the total active power adjustment amount is less than zero, the target quadrant is the first quadrant.

9. The method according to any one of claims 1 to 8, characterized in that The new energy device includes a wind turbine and / or a photovoltaic device; The power influencing parameters include wind speed and / or light intensity.

10. A frequency regulating device for an electric power system, characterized in that: The power system includes a new energy device and an energy storage unit, the energy storage unit is connected to the new energy device, the new energy device is connected to the power grid through a grid connection point, and the frequency adjustment device includes: The adjustment amount acquisition module is used to obtain the total active power adjustment amount based on the frequency modulation parameters and the preset frequency and power droop control characteristic model when it is determined that the frequency modulation stage has been entered; A regulation amount allocation module, used to split the total active power regulation amount according to the power regulation capability parameter of the new energy device, the power regulation capability parameter of the energy storage unit and the power influence parameter of the new energy device, and obtain the active power regulation amount of each new energy device and the active power regulation amount of each energy storage unit, wherein the power influence parameter is positively correlated with the active power regulation amount of the new energy device; The control module is used to control each of the new energy devices to operate according to the corresponding active power adjustment amount, and to control each of the energy storage units to operate according to the corresponding active power adjustment amount to achieve frequency regulation.

11. A controller, characterized in that: Applied to an electric power system, the electric power system comprises a new energy device and an energy storage unit, the energy storage unit is connected to the new energy device, and the new energy device is connected to a power grid via a grid connection point; The controller comprises: a processor and a memory storing computer program instructions; when the processor executes the computer program instructions, the frequency regulation method of the power system as claimed in any one of claims 1 to 9 is implemented.

12. A power system, characterized in that: include: New energy devices are connected to the grid through grid connection points; An energy storage unit connected to the new energy device; The controller as claimed in claim 11, wherein the controller is used to control the new energy device and the energy storage unit.

13. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer program instructions, and when the computer program instructions are executed by a processor, the frequency regulation method of the power system according to any one of claims 1 to 9 is implemented.

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