Auxiliary frequency modulation method and device based on new energy frequency modulation flexible aggregate

Abstract

The application provides an auxiliary frequency modulation method and device based on a new energy frequency modulation flexible polymer, and belongs to the field of power system frequency modulation. The method determines corresponding target frequency modulation equipment for auxiliary frequency modulation based on the difference between the power system frequency and the rated frequency, improves the flexibility of power system frequency modulation, and obtains the droop control curve of the target frequency modulation equipment based on preset expected frequency modulation speed information, so that the control strategy can be adaptively adjusted according to different operation and demand, the adaptability and stability of the system are improved, and the frequency stability and response speed of the power system are improved, so that accurate control of the system frequency can be realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of power system frequency modulation, and in particular to an auxiliary frequency modulation method based on a new energy frequency modulation flexible aggregate. BACKGROUND

[0002] With the large-scale access of distributed new energy, the frequency modulation demand of the power system has also changed. On the one hand, the randomness and volatility of new energy have brought challenges to the frequency stability of the power system; on the other hand, the access of new energy has also increased the complexity and uncertainty of the power system. Power system frequency modulation is an important link to ensure the stable operation of the power grid. Therefore, how to effectively utilize distributed new energy for auxiliary frequency modulation has become an important issue faced by the power system.

[0003] However, the droop control strategy of the traditional new energy-based frequency modulation method is often linear, and the droop control parameters are constant, which can easily affect the stability and power quality of the power system and cannot achieve accurate control of the system frequency. SUMMARY

[0004] The embodiments of the present application provide an auxiliary frequency modulation method and device based on a new energy frequency modulation flexible aggregate to solve the problem of being unable to achieve accurate control of the system frequency.

[0005] In a first aspect, the embodiments of the present application provide an auxiliary frequency modulation method based on a new energy frequency modulation flexible aggregate, comprising:

[0006] acquiring a power system frequency and determining whether the power system frequency is within a frequency modulation action interval;

[0007] If the power system frequency is within the frequency modulation action interval, a target frequency modulation device in a new energy frequency modulation flexible aggregate is determined according to the difference between the power system frequency and a rated frequency; wherein the new energy frequency modulation flexible aggregate includes a photovoltaic inverter, an energy storage converter and a charging pile, and the target frequency modulation device is one or more devices in the new energy frequency modulation flexible aggregate;

[0008] obtaining a droop control curve of the target frequency modulation device based on preset expected frequency modulation speed information; wherein the droop control curve is used to indicate the corresponding relationship between the output frequency of the target frequency modulation device and the power system frequency, and the expected frequency modulation speed information is used to indicate the curve slope of the corresponding droop control curve of the target frequency modulation device;

[0009] adjusting the output power of the target frequency modulation device based on the droop control curve to assist the thermal power unit in adjusting the frequency of the power system and maintaining the frequency stability of the power system.

[0010] In a possible implementation, the obtaining, based on preset expected frequency modulation speed information, of a droop control curve of the target frequency modulation device comprises:

[0011] obtaining a frequency interval in which the droop control curve acts;

[0012] determining, based on the expected frequency modulation speed information, power output values of the target frequency modulation device at boundary points and median points of the frequency interval;

[0013] obtaining a preset curve expression; wherein the preset curve expression includes a to-be-solved parameter;

[0014] determining, according to the power output values of the target frequency modulation device at the boundary points and the median points of the frequency interval, a value of the to-be-solved parameter in the preset curve expression, and obtaining the droop control curve of the target frequency modulation device based on the value of the to-be-solved parameter; wherein the droop control curve is used to indicate a corresponding relationship between an output frequency of the target frequency modulation device and a frequency of a power system within the frequency interval.

[0015] In a possible implementation, the determining, according to a difference between the frequency of the power system and a rated frequency, of the target frequency modulation device in the new energy frequency modulation flexible aggregate comprises:

[0016] if the difference is positive, determining that the target frequency modulation device includes a photovoltaic inverter and an energy storage converter, and controlling a working state of the energy storage converter to be a charging state;

[0017] if the difference is negative, determining that the target frequency modulation device includes a charging pile and an energy storage converter, and controlling a working state of the energy storage converter to be a discharging state.

[0018] In a possible implementation, the frequency modulation action interval includes a first interval and a second interval;

[0019] the obtaining of the frequency interval in which the droop control curve acts comprises:

[0020] if the target frequency modulation device includes the photovoltaic inverter and the energy storage converter, determining that the frequency interval in which the droop control curve acts is the first interval; wherein a sum of a rated frequency of a power system and a first preset threshold is a first boundary point of the first interval, and a sum of the rated frequency and a second preset threshold is a second boundary point of the first interval; the second preset threshold is greater than the first preset threshold;

[0021] If the target frequency modulation device comprises a charging pile and an energy storage converter, the frequency range in which the droop control curve acts is determined as the second range; wherein the difference between the rated frequency and the second preset threshold is a first boundary point of the second range, and the difference between the rated frequency and the first preset threshold is a second boundary point of the second range.

[0022] In a possible implementation, the preset curve expression is a quadratic polynomial curve, and the parameters to be solved include a quadratic term coefficient, a linear term coefficient, and a constant term.

[0023] The determination of the values of the parameters to be solved in the preset curve expression according to the power output values of the target frequency modulation device at the boundary points and the median point of the frequency range, and the obtaining of the droop control curve of the target frequency modulation device based on the values of the parameters to be solved, comprise:

[0024] The solving of the preset curve expression according to the power output values of the target frequency modulation device at the first boundary point, the second boundary point, and the median point of the frequency range, to determine the values of the quadratic term coefficient, the linear term coefficient, and the constant term in the preset curve expression.

[0025] The obtaining of the droop control curve of the target frequency modulation device according to the values of the quadratic term coefficient, the linear term coefficient, and the constant term in the preset curve expression.

[0026] In a possible implementation, after the adjustment of the output power of the target frequency modulation device based on the droop control curve to assist the thermal power generating unit in regulating the frequency of the power system, the method further comprises:

[0027] Monitoring the frequency of the power system.

[0028] If the absolute value of the difference between the frequency of the power system and the rated frequency is less than the first preset threshold, it is determined that the frequency of the power system is in a stable state, and the output power of the target frequency modulation device is controlled to return to the output power before frequency modulation.

[0029] In a possible implementation, after the determination that the frequency of the power system is in a stable state, the method further comprises:

[0030] According to The evaluation index of the joint frequency modulation is calculated.

[0031] Wherein, Q f is the evaluation index, T is the time interval, t over is the time at which the absolute value of the difference between the frequency of the power system and the rated frequency exceeds the first preset threshold within the time period T, f NΔf is the absolute value of the difference between the power system frequency and the rated frequency over Δf is the absolute value of the difference between the power system frequency and the rated frequency over Δf is the absolute value of the difference between the power system frequency and the rated frequency Δf is the first preset threshold value;

[0032] Based on the evaluation index, the expected frequency modulation speed information is adjusted.

[0033] In a possible implementation, after the power system frequency is obtained and it is determined whether the power system frequency is within the frequency modulation action interval, the method further includes:

[0034] If the power system frequency is not within the frequency modulation action interval, the absolute value of the difference between the power system frequency and the rated frequency is determined.

[0035] If the absolute value of the difference is less than a first preset threshold value, the new energy frequency modulation flexible aggregate is instructed to maintain the current working state.

[0036] If the absolute value of the difference is greater than a second preset threshold value, it is determined that the power system has a fault, and fault prompt information is output.

[0037] In a second aspect, an auxiliary frequency modulation device based on a new energy frequency modulation flexible aggregate is provided, and includes:

[0038] An acquisition unit is configured to acquire a power system frequency and determine whether the power system frequency is within a frequency modulation action interval.

[0039] A first processing unit is configured to, if the power system frequency is within the frequency modulation action interval, determine a target frequency modulation device in a new energy frequency modulation flexible aggregate according to a difference between the power system frequency and a rated frequency. The new energy frequency modulation flexible aggregate includes a photovoltaic inverter, an energy storage converter, and a charging pile, and the target frequency modulation device is one or more devices in the new energy frequency modulation flexible aggregate.

[0040] A second processing unit is configured to obtain a droop control curve of the target frequency modulation device based on preset expected frequency modulation speed information. The droop control curve is used to indicate a corresponding relationship between an output frequency of the target frequency modulation device and a power system frequency, and the expected frequency modulation speed information is used to indicate a curve slope of the corresponding droop control curve of the target frequency modulation device.

[0041] The third processing unit is configured to adjust the output power of the target frequency modulation device based on the droop control curve, so as to assist the thermal power unit in adjusting the frequency of the power system and maintaining the stability of the frequency of the power system.

[0042] In a possible implementation, the second processing unit is specifically configured to:

[0043] obtain a frequency range in which the droop control curve acts;

[0044] determine power output values of the target frequency modulation device at a boundary point and a median point of the frequency range based on the expected frequency modulation speed information;

[0045] obtain a preset curve expression; wherein the preset curve expression includes a to-be-solved parameter;

[0046] determine a value of the to-be-solved parameter in the preset curve expression according to the power output values of the target frequency modulation device at the boundary point and the median point of the frequency range, and obtain the droop control curve of the target frequency modulation device based on the value of the to-be-solved parameter; wherein the droop control curve is used to indicate a corresponding relationship between the output frequency of the target frequency modulation device and the frequency of the power system within the frequency range.

[0047] The embodiments of the present application provide an auxiliary frequency modulation method and device based on a new energy frequency modulation flexible aggregate. When the frequency of the power system is within a frequency modulation action range, a target frequency modulation device in the new energy frequency modulation flexible aggregate is determined according to a difference between the frequency of the power system and a rated frequency; wherein the new energy frequency modulation flexible aggregate includes a photovoltaic inverter, an energy storage converter and a charging pile, and the target frequency modulation device is one or more devices in the new energy frequency modulation flexible aggregate. Then, a droop control curve of the target frequency modulation device is obtained based on preset expected frequency modulation speed information. Finally, the output power of the target frequency modulation device is adjusted based on the droop control curve, so as to assist the thermal power unit in adjusting the frequency of the power system and maintaining the stability of the frequency of the power system. The method determines the corresponding target frequency modulation device for auxiliary frequency modulation based on the difference between the frequency of the power system and the rated frequency, improves the flexibility of frequency modulation of the power system, and obtains the droop control curve of the target frequency modulation device based on the preset expected frequency modulation speed information, so that the control strategy can be adaptively adjusted according to different operation and requirements, the adaptability and stability of the system are improved, and the frequency stability and response speed of the power system are improved, so that the system frequency can be accurately regulated and controlled. BRIEF DESCRIPTION OF DRAWINGS

[0048] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor.

[0049] Figure 1 is an implementation flowchart of the auxiliary frequency modulation method based on the new energy frequency modulation flexible aggregate provided by the embodiments of the present application;

[0050] Figure 2 is an implementation flowchart of another auxiliary frequency modulation method based on the new energy frequency modulation flexible aggregate provided by the embodiments of the present application;

[0051] Figure 3 is a droop control curve diagram corresponding to a photovoltaic inverter provided by the embodiments of the present application;

[0052] Figure 4 is a droop control curve diagram corresponding to an energy storage converter provided by the embodiments of the present application;

[0053] Figure 5 is a droop control curve diagram corresponding to a charging pile provided by the embodiments of the present application;

[0054] Figure 6 is a power recovery diagram of a photovoltaic inverter provided by the embodiments of the present application;

[0055] Figure 7 is a structure diagram of the auxiliary frequency modulation device based on the new energy frequency modulation flexible aggregate provided by the embodiments of the present application. DETAILED DESCRIPTION

[0056] In the following description, specific details are set forth in order to provide a thorough understanding of the embodiments of the present application. However, persons skilled in the art should understand that the present application can also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary details. SUMMARY

[0058] With the increasing emphasis on environmental protection and sustainable development worldwide, energy transformation has become an irreversible trend. Traditional fossil energy is gradually being replaced by new energy due to its limited nature and environmental pollution problems. Distributed new energy, such as wind energy and solar energy, has become an important direction for the development of new energy due to its clean, renewable, and widespread characteristics. These distributed new energy sources are usually connected to the medium and low voltage distribution network system, providing a rich source of energy for the power system. With the large-scale access of distributed new energy, the frequency regulation requirements of the power system have also changed. On the one hand, the randomness and volatility of new energy pose challenges to the frequency stability of the power system; on the other hand, the access of new energy also increases the complexity and uncertainty of the power system. Power system frequency regulation is an important part of ensuring the stable operation of the power grid. Therefore, how to effectively utilize distributed new energy for auxiliary frequency regulation has become an important issue facing the power system.

[0059] The inventors have found that traditional droop control is based on the power output characteristics of synchronous generators, and by controlling the output voltage and frequency of micro-sources, a completely autonomous control system is formed. However, in the process of achieving system power balance, droop control can cause voltage to drop. That is, the realization of power balance is at the expense of voltage drop. This voltage drop may affect the stability and power quality of the power system. In addition, the selection of droop coefficients is also crucial, as it not only affects the effectiveness of power distribution, but also relates to the deviation of frequency and voltage. In practical applications, the droop coefficients cannot meet the adaptability problems in different scenarios or complex situations, and constant control parameters cannot achieve accurate control of the system frequency. Therefore, there are stability and accuracy problems in the droop control of the power system in the prior art.

[0060] In order to improve the frequency stability of the power system and achieve accurate control of the system frequency, in the embodiments of the present application, the power system frequency is monitored, and based on the difference between the power system frequency and the rated frequency, the corresponding target frequency regulation device is determined to assist in frequency regulation, improving the flexibility of power system frequency regulation. Moreover, based on the preset expected frequency regulation speed information, the droop control curve of the target frequency regulation device is obtained, which can adaptively adjust the control strategy according to the different operating states and demands of the power system, improving the adaptability and stability of the system, thereby improving the frequency stability and response speed of the power system, and achieving accurate control of the system frequency.

[0061] To make the objectives, technical solutions, and advantages of the present application clearer, specific embodiments will be described below with reference to the accompanying drawings.

[0062] Figure 1 The implementation flowchart of the auxiliary frequency regulation method based on the new energy frequency regulation flexible aggregate provided by the embodiments of the present application is described in detail as follows:

[0063] Step 101, acquire the power system frequency, and determine whether the power system frequency is in the frequency regulation action interval.

[0064] Illustratively, the embodiment acquires the power system frequency value in real time, and determines whether the power system frequency is in the frequency regulation action interval based on preset conditions.

[0065] The frequency regulation action interval refers to the frequency range in which power generation equipment or energy storage systems adjust power to maintain system frequency stability when the power system frequency exceeds the frequency dead zone.

[0066] The frequency dead zone refers to a small range interval around the rated frequency in the power system frequency regulation process. In this interval, the power generation equipment does not perform frequency regulation. This is because the power system frequency will have small fluctuations during normal operation. To avoid unnecessary equipment wear and energy loss caused by frequent power adjustment by power generation equipment, a frequency dead zone is set.

[0067] The rated frequency of the power system refers to the standard frequency of alternating current in the power system under normal operating conditions.

[0068] Step 102, if the power system frequency is in the frequency regulation action interval, determine the target frequency regulation device in the new energy frequency regulation flexible aggregate according to the difference between the power system frequency and the rated frequency; wherein the new energy frequency regulation flexible aggregate includes a photovoltaic inverter, an energy storage converter, and a charging pile, and the target frequency regulation device is one or more devices in the new energy frequency regulation flexible aggregate.

[0069] Illustratively, if the determination result is that the power system frequency is in the frequency regulation action interval, the embodiment determines one or more devices in the new energy frequency regulation flexible aggregate as the target frequency regulation device according to the difference between the power system frequency and the rated frequency.

[0070] For example, if the difference between the power system frequency and the rated frequency is positive, it indicates that the current power system energy is in a surplus state, and the target frequency regulation device needs to absorb energy. Therefore, the target frequency regulation device includes the photovoltaic inverter and the energy storage converter, and the working state of the energy storage converter is controlled to be in the charging state.

[0071] In a feasible implementation, when the difference between the power system frequency and the rated frequency is positive, the embodiment can also use the photovoltaic inverter or the energy storage converter in the charging state as the target frequency regulation device.

[0072] If the difference is negative, it indicates that the current power system energy is in a state of deficiency, and the target frequency modulation device needs to release energy, so the target frequency modulation device is determined to include a charging pile and a energy storage converter, and the working state of the energy storage converter is controlled to be a discharging state.

[0073] In a feasible implementation, when the difference is negative, the charging pile or the energy storage converter in the discharging state can also be used as the target frequency modulation device.

[0074] In step 103, a droop control curve of the target frequency modulation device is obtained based on preset expected frequency modulation speed information, wherein the droop control curve is used to indicate the corresponding relationship between the output frequency of the target frequency modulation device and the frequency of the power system, and the expected frequency modulation speed information is used to indicate the curve slope of the droop control curve corresponding to the target frequency modulation device.

[0075] For example, the expected frequency modulation speed information can be predefined to indicate the curve slope of the droop control curve corresponding to the target frequency modulation device. Therefore, after the target frequency modulation device is determined, the preset expected frequency modulation speed information is obtained, and based on the expected frequency modulation speed information, the droop control curve corresponding to each of the one or more target frequency modulation devices is determined.

[0076] The expected frequency modulation speed information is set according to the capacity of the light-storage-load flexible polymer auxiliary frequency modulation and the expected frequency modulation speed. In the embodiment, the new energy frequency modulation flexible polymer can be a light-storage-load flexible polymer, including a photovoltaic inverter, an energy storage converter, and a charging pile.

[0077] In step 104, the output power of the target frequency modulation device is adjusted based on the droop control curve, so as to assist the thermal power unit in adjusting the frequency of the power system and maintaining the frequency stability of the power system.

[0078] For example, based on the obtained droop control curve, the output power of the corresponding target frequency modulation device is adjusted to release energy or absorb system energy, so as to assist the thermal power unit in adjusting the frequency of the power system and maintaining the frequency stability of the power system.

[0079] In summary, the embodiment determines the corresponding target frequency modulation device to assist in frequency modulation based on the difference between the frequency of the power system and the rated frequency, thereby improving the flexibility of power system frequency modulation. Moreover, the droop control curve of the target frequency modulation device is obtained based on the preset expected frequency modulation speed information, so that the control strategy can be adaptively adjusted according to different operation and requirements, thereby improving the adaptability and stability of the system, and the frequency stability and response speed of the power system are improved, and accurate control of the system frequency can be realized.

[0080] The embodiment determines the corresponding target frequency modulation device according to the difference between the power system frequency and the rated frequency, and controls the target frequency modulation device to be in the corresponding working state, so as to facilitate auxiliary frequency modulation. In addition, the embodiment determines the power output values of the target frequency modulation device at the boundary points and the median points of the frequency interval based on the expected frequency modulation speed information, and then solves the quadratic polynomial curve based on the power output values of the target frequency modulation device at the boundary points and the median points of the frequency interval, to obtain the corresponding droop curve, so that the droop curve is quickly and accurately solved, and the response speed of frequency modulation is improved. Furthermore, the embodiment constructs an evaluation index of frequency modulation, and adjusts the expected frequency modulation speed information based on the evaluation index, so that the frequency modulation control strategy can be optimized, the frequency stability and the response speed of the power system are further improved, and the system frequency is accurately controlled.

[0081] Figure 2 Another implementation flowchart of the auxiliary frequency modulation method based on the new energy frequency modulation flexible aggregate provided by the embodiment is provided, and is described in detail as follows.

[0082] In step 201, the power system frequency is obtained, and it is determined whether the power system frequency is in the frequency modulation action interval.

[0083] In a feasible implementation manner, if the power system frequency is not in the frequency modulation action interval, the absolute value of the difference between the power system frequency and the rated frequency is determined. If the absolute value of the difference is less than a first preset threshold, the new energy frequency modulation flexible aggregate is instructed to maintain the current working state. If the absolute value of the difference is greater than a second preset threshold, it is determined that the power system has a fault, and fault prompt information is output.

[0084] For example, the first preset threshold can be a frequency dead zone. The sum of the second preset threshold and the rated frequency is the maximum value of the frequency modulation action interval, and the rated frequency minus the second preset threshold is the minimum value of the frequency modulation action interval. That is, if the absolute value of the difference between the power system frequency and the rated frequency is less than the first preset threshold, it is considered that the power system frequency is in a normal fluctuation range, and frequency modulation processing is not required. If the absolute value of the difference between the power system frequency and the rated frequency is greater than the second preset threshold, it is determined that the power system has a fault, and emergency measures need to be taken.

[0085] In one example, the embodiment determines the frequency modulation action interval [fmin,(f N , the frequency dead zone f de , the minimum value f min of the frequency modulation action interval, and the maximum value f max of the frequency modulation action interval based on the rated frequency f N -fde), [(f N +fde), fmax]. That is, when the power system frequency (f N -fde N de min max

[0086] In an example, the power system frequency deviation is calculated according to the load dynamic condition at the current time, and it is determined whether the power system frequency is in the frequency regulation action range.

[0087] In step 202, if the power system frequency is in the frequency regulation action range, a target frequency regulation device in the new energy frequency regulation flexible aggregate is determined according to the difference between the power system frequency and the rated frequency; the new energy frequency regulation flexible aggregate includes a photovoltaic inverter, an energy storage converter, and a charging pile, and the target frequency regulation device is one or more devices in the new energy frequency regulation flexible aggregate.

[0088] In an example, step 202 includes the following steps:

[0089] If the difference is positive, the target frequency regulation device includes the photovoltaic inverter and the energy storage converter, and the working state of the energy storage converter is controlled to be in the charging state.

[0090] If the difference is negative, the target frequency regulation device includes the charging pile and the energy storage converter, and the working state of the energy storage converter is controlled to be in the discharging state.

[0091] For example, the present embodiment refers to step 102, and will not be described again.

[0092] In step 203, a frequency range in which the droop control curve acts is obtained.

[0093] In an example, the frequency regulation action range includes a first range and a second range; and step 203 includes the following steps:

[0094] If the target frequency regulation device includes the photovoltaic inverter and the energy storage converter, it is determined that the frequency range in which the droop control curve acts is the first range; the sum of the rated frequency of the power system and the first preset threshold is the first boundary point of the first range, and the sum of the rated frequency and the second preset threshold is the second boundary point of the first range; the second preset threshold is greater than the first preset threshold.

[0095] ​​​​​If the target frequency regulation equipment includes charging piles and energy storage converters, then the frequency range in which the droop control curve acts is determined as the second range; wherein, the difference between the rated frequency and the second preset threshold is the first boundary point of the second range, and the difference between the rated frequency and the first preset threshold is the second boundary point of the second range.

[0096] For example, the frequency modulation operating range consists of two parts, including a first range and a second range, i.e., [f min ,(f N -f de )]、[(f N +f de ),f max Among them, [(f N +f de ),f max ] represents the first interval, [f min ,(f N -f de )] is the second interval.

[0097] Step 204: Based on the desired frequency modulation speed information, determine the power output value of the target frequency modulation device at the boundary point and median point of the frequency range; wherein, the desired frequency modulation speed information is used to indicate the slope of the droop control curve corresponding to the target frequency modulation device.

[0098] For example, the desired frequency regulation speed information is based on the frequency regulation capability assisted by the photovoltaic-storage-load flexible polymer and the setting of the desired frequency regulation speed. In this embodiment, the new energy frequency regulation flexible polymer can be a photovoltaic-storage-load flexible polymer, including a photovoltaic inverter, an energy storage converter, and a charging pile.

[0099] In one example, the desired frequency modulation speed information can be defined by taking the value of the midpoint of the frequency modulation interval in the droop curve corresponding to the target frequency modulation device, so as to indicate the power of the droop curve.

[0100] In one feasible implementation, in the photovoltaic-storage-load flexible polymer, the coordinates of the upper boundary point, median point, and lower boundary point of the frequency modulation interval corresponding to the photovoltaic inverter can be respectively (f N +f de ,1) and (f max ,0); where the horizontal axis represents the current power system frequency, and the vertical axis represents the photovoltaic inverter power value corresponding to the current power system frequency.

[0101] In the flexible photovoltaic-storage-charge composite, the coordinates of the lower boundary point, median point, and upper boundary point of the charging pile frequency modulation range can be respectively (f min ,0) and (f N -f de,1); where the horizontal axis represents the current power system frequency, and the vertical axis represents the charging pile power value corresponding to the current power system frequency.

[0102] In the flexible photovoltaic-storage-charge composite, the coordinates of the upper boundary, middle, and lower boundary points of the frequency regulation range of the energy storage converter, and the discharge stages are respectively (f min ,1) and (f N -f de ,0); the charging stages can be (f N +f de ,0) and (f max ,-1); where the horizontal axis represents the current power system frequency, and the vertical axis represents the power value of the energy storage converter corresponding to the current power system frequency. The power during the energy storage discharge stage is defined as a positive value, and the power during the charging stage is defined as a negative value.

[0103] In this embodiment, the power of the target frequency modulation device is expressed in per-unit value, and the power reference value is the rated power of each target frequency modulation device.

[0104] Step 205: Obtain the preset curve expression, and determine the values ​​of the parameters to be solved in the preset curve expression based on the power output values ​​of the target frequency modulation equipment at the boundary points and median points of the frequency range. Based on the values ​​of the parameters to be solved, obtain the droop control curve of the target frequency modulation equipment. The preset curve expression includes the parameters to be solved, and the droop control curve is used to indicate the correspondence between the output frequency of the target frequency modulation equipment and the frequency of the power system within the frequency range.

[0105] In one feasible implementation, the preset curve expression is a quadratic polynomial curve, and the parameters to be solved include the coefficients of the quadratic term, the coefficients of the linear term, and the constant term; step 205 includes:

[0106] Based on the power output values ​​of the target frequency modulation device at the first boundary point, the second boundary point, and the midpoint of the frequency range, the preset curve expression is solved to determine the values ​​of the quadratic coefficient, the linear coefficient, and the constant term in the preset curve expression.

[0107] Based on the values ​​of the quadratic coefficient, the linear coefficient, and the constant term in the preset curve expression, the droop control curve of the target frequency modulation device is obtained.

[0108] For example, in this embodiment, based on the characteristics of the photovoltaic inverter participating in grid frequency regulation in the photovoltaic-storage-load flexible polymer, the quadratic polynomial curve expression function corresponding to the photovoltaic inverter is determined to be P1=a1f. 2 +b1f+c1,(f N +f de)≤f≤f max ; wherein, P1 is the output power of the photovoltaic inverter, f is the current power system frequency, a1, b1, c1 are function expression coefficients respectively, the rated frequency is f N , the frequency dead zone is f de , and the maximum value of the frequency action interval is f max .

[0109] According to the characteristics of the charging pile participating in the frequency regulation of the power grid in the light-storage-load flexible polymer, the quadratic polynomial curve expression function corresponding to the charging pile is determined as P2=a2f 2 +b2f+c2,f min ≤f≤(f N -f de ); wherein, P2 is the output power of the charging pile, f is the current power system frequency, a2, b2, c2 are function expression coefficients respectively, the rated frequency is f N , the frequency dead zone is f de , and the minimum value of the frequency action interval is f min .

[0110] According to the characteristics of the energy storage converter participating in the frequency regulation of the power grid in the light-storage-load flexible polymer, the quadratic polynomial curve expression function corresponding to the energy storage converter is determined as:

[0111]

[0112] wherein, P3 is the output power of the energy storage converter, f is the current power system frequency, the rated frequency is f N , the frequency dead zone is f de , the minimum value of the frequency action interval is f min , the maximum value of the frequency action interval is f max , when f min ≤f≤(f N -f de ), the energy storage system is in the discharging state, when (f N +f de )≤f≤f max , the energy storage system is in the charging state, a3, b3, c3, a4, b4, c4 are function expression coefficients respectively.

[0113] The embodiment solves the to-be-solved parameters corresponding to the photovoltaic inverter, the charging pile and the energy storage converter in the light-storage-load flexible polymer by respectively substituting the coordinate values of the upper boundary value point, the middle value point and the lower boundary value point of the corresponding frequency modulation interval into the quadratic polynomial curve expression, so that the power system can be accurately assisted in frequency modulation based on the to-be-solved parameters accurately calculated subsequently.

[0114] Substitute the coordinate values of the upper boundary value point, the middle value point and the lower boundary value point in the frequency modulation interval into the quadratic polynomial curve expression respectively, and solve the coefficients of the droop control curve function expression of the photovoltaic inverter in the light-storage-load flexible aggregation Solve a1, b1, c1.

[0115] Substitute the coordinate values of the upper boundary value point, the middle value point and the lower boundary value point in the frequency modulation interval into the quadratic polynomial curve expression respectively, and solve the coefficients of the droop control curve function expression of the charging pile in the light-storage-load flexible aggregation Solve a2, b2, c2.

[0116] Substitute the coordinate values of the upper boundary value point, the middle value point and the lower boundary value point in the frequency modulation interval into the quadratic polynomial curve expression respectively, and solve the coefficients of the droop control curve function expression of the energy storage converter in the light-storage-load flexible aggregation Solve a3, b3, c3, a4, b4, c4.

[0117] In one example, the droop control curves corresponding to the photovoltaic inverter, the energy storage converter and the charging pile obtained by the embodiment are as shown in Figures 3 to 5 , wherein the horizontal coordinate of the curve is frequency, and the unit is hertz (Hz); and the vertical coordinate of the curve is the power corresponding to the device, and the unit is kilowatt (kW). As shown in Figure 3 , the curve of the droop control curve corresponding to the photovoltaic inverter gradually decreases in slope from (f1, A) to (f2, B) to (f3, C) with the increase of the output power. max , C) to (f2, B) to (f1, A). Figure 5 , C) to (f2, B) to (f1, A). min , D) to (f3, E) to (f4, F). As shown in Figure 3 and Figure 5 , the droop control curve presents an S shape, that is, the change rate of the frequency and the amplitude of the output voltage gradually decreases with the increase of the output power, and this S-shaped characteristic helps to reduce the fluctuation of the frequency and the voltage. Compared with the traditional droop control algorithm, through the flexible control of the light-storage-load flexible aggregation, the frequency modulation can be assisted, the combined frequency modulation with the thermal power unit can be realized, and thus the frequency stability and the response speed of the power system can be improved.

[0118] In addition, the droop control divides the droop control curve into multiple intervals, each interval corresponds to different control parameters and slopes, so that the control strategy can automatically adjust the control parameters according to different operation and demand, improve the adaptability and stability of the system, and in each segmented interval, the droop control curve presents an S shape, which ensures the accurate control of the light-storage-load flexible aggregation, and thus the frequency stability and the response speed of the power system can be improved. Referring to Figure 4 , Figure 4 (f min(f1, D), (f2, E), (f3, B), (f4, A) divide the left sag control curve into multiple intervals, each of which corresponds to different control parameters and slopes; Figure 4 (f1, D), (f2, E), (f max (f3, B), (f4, A) divide the right sag control curve into multiple intervals, each of which corresponds to different control parameters and slopes.

[0119] Step 206, based on the sag control curve, adjust the output power of the target frequency modulation device to assist the thermal power unit to adjust the frequency of the power system, and maintain the frequency stability of the power system.

[0120] Exemplarily, when the frequency drops, the target frequency modulation device increases the power output to make up for the power shortage of the system, reduces the adjustment burden of the thermal power unit, and helps the thermal power unit to have enough time to adjust its output power, so that the system frequency rises to the normal range. Similarly, when the frequency rises, the target frequency modulation device reduces the power output, and the thermal power unit maintains the stability of the system frequency together.

[0121] Step 207, monitor the frequency of the power system, if the absolute value of the difference between the frequency of the power system and the rated frequency is less than the first preset threshold, it is determined that the frequency of the power system is in a stable state, and the output power of the target frequency modulation device is controlled to return to the output power before frequency modulation.

[0122] Exemplarily, after adjusting the output power of the target frequency modulation device based on the sag control curve to assist the thermal power unit to adjust the frequency of the power system, the embodiment monitors the frequency of the power system in real time, if the absolute value of the difference between the frequency of the power system and the rated frequency is less than the first preset threshold, it is determined that the frequency of the power system is in a stable state, or if the absolute value of the difference between the frequency of the power system and the rated frequency is less than the first preset threshold in a time period greater than or equal to a preset time, it is determined that the frequency of the power system is in a stable state, after determining that the frequency of the power system is in a stable state, the embodiment controls the output power of the target frequency modulation device to return to the output power before frequency modulation.

[0123] Figure 6 is a power recovery schematic diagram of an inverter device provided by the embodiment of the present application; as shown in Figure 6 , assuming that the power value of the inverter device changes from P t1 to P t2 , the power of the inverter device starts to recover after 15s when the frequency of the power system is in a stable state, and is recovered linearly to P t1 in 2s according to the P-t expression.

[0124] The P-t expression is:

[0125]

[0126] wherein P is the power value of the inverter device, t is the time after the power of the photovoltaic inverter or the charging pile changes, P t1 is the power value before the inverter operates, P t2 is the power value after the inverter operates.

[0127] In an implementable embodiment, after determining that the frequency of the power system is in a stable state, the embodiment calculates the evaluation index of the joint frequency modulation according to Q f The smaller the evaluation index is, the better the frequency modulation effect is. Wherein Q f is the evaluation index, T is the time interval, t over is the time when the absolute value of the difference between the frequency of the power system and the rated frequency exceeds the first preset threshold value within the time period T, f N is the rated frequency, Δf over is the deviation when the absolute value of the difference between the frequency of the power system and the rated frequency exceeds the first preset threshold value, f over is the frequency value when the absolute value of the difference between the frequency of the power system and the rated frequency exceeds the first preset threshold value, f Δf is the first preset threshold value.

[0128] Based on the evaluation index, the expected frequency modulation speed information is adjusted. For example, if the evaluation index Q f is larger, the expected frequency modulation speed can be increased.

[0129] In summary, the auxiliary frequency modulation method based on the new energy frequency modulation flexible aggregate provided by the embodiment has more flexible and accurate control than the traditional droop control. When external disturbance occurs in the system and causes the frequency of the power grid to deviate, the new energy auxiliary frequency modulation method provided by the embodiment can fully integrate the light-storage-load flexible aggregate composed of photovoltaic, energy storage and charging piles, analyze and study the group characteristics and effects of the light-storage-load flexible aggregate, so that the light-storage-load flexible aggregate has the ability to participate in the frequency modulation of the power grid, can quickly respond to the frequency change of the system, quickly provide active output, and effectively improve the inertia / frequency stability level of the new power system.

[0130] It should be understood that the size of the serial number of each step in the above embodiment does not mean the order of execution, and the execution order of each process should be determined according to its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiment of the present application.

[0131] The following is a device embodiment of the present application. For details not described in detail, reference can be made to the corresponding method embodiments described above.

[0132] Figure 7A structural schematic diagram of the auxiliary frequency modulation device based on the new energy frequency modulation flexible aggregate is shown. For ease of illustration, only parts related to the embodiments of the present application are shown, and are described in detail as follows.

[0133] As shown in Figure 7 The auxiliary frequency modulation device 7 based on the new energy frequency modulation flexible aggregate includes:

[0134] The acquisition unit 71 is configured to acquire the power system frequency and determine whether the power system frequency is within the frequency modulation action interval.

[0135] The first processing unit 72 is configured to determine the target frequency modulation device in the new energy frequency modulation flexible aggregate according to the difference between the power system frequency and the rated frequency if the power system frequency is within the frequency modulation action interval; wherein the new energy frequency modulation flexible aggregate includes a photovoltaic inverter, an energy storage converter, and a charging pile, and the target frequency modulation device is one or more devices in the new energy frequency modulation flexible aggregate.

[0136] The second processing unit 73 is configured to obtain the droop control curve of the target frequency modulation device based on the preset expected frequency modulation speed information; wherein the droop control curve is used to indicate the corresponding relationship between the output frequency of the target frequency modulation device and the power system frequency, and the expected frequency modulation speed information is used to indicate the curve slope of the corresponding droop control curve of the target frequency modulation device.

[0137] The third processing unit 74 is configured to adjust the output power of the target frequency modulation device based on the droop control curve to assist the thermal power unit in adjusting the frequency of the power system and maintaining the frequency stability of the power system.

[0138] In one possible implementation, the second processing unit 73 is specifically configured to:

[0139] acquire the frequency interval in which the droop control curve acts.

[0140] determine the power output values of the target frequency modulation device at the boundary points and the median points of the frequency interval based on the expected frequency modulation speed information.

[0141] acquire a preset curve expression; wherein the preset curve expression includes a to-be-solved parameter.

[0142] determine the value of the to-be-solved parameter in the preset curve expression according to the power output values of the target frequency modulation device at the boundary points and the median points of the frequency interval, and obtain the droop control curve of the target frequency modulation device based on the value of the to-be-solved parameter; wherein the droop control curve is used to indicate the corresponding relationship between the output frequency of the target frequency modulation device and the power system frequency within the frequency interval.

[0143] In one possible implementation, the first processing unit 72 is specifically configured to:

[0144] If the difference is positive, it is determined that the target frequency regulating device comprises a photovoltaic inverter and an energy storage converter, and the working state of the energy storage converter is controlled to be a charging state.

[0145] If the difference is negative, it is determined that the target frequency regulating device comprises a charging pile and an energy storage converter, and the working state of the energy storage converter is controlled to be a discharging state.

[0146] In a possible implementation, the frequency regulating action interval comprises a first interval and a second interval; and the second processing unit 73 is specifically configured to:

[0147] If the target frequency regulating device comprises a photovoltaic inverter and an energy storage converter, the frequency interval in which the droop control curve acts is determined to be the first interval; wherein the sum of the rated frequency of the power system and the first preset threshold value is a first boundary point of the first interval, and the difference between the rated frequency and the second preset threshold value is a second boundary point of the first interval; the second preset threshold value is greater than the first preset threshold value.

[0148] If the target frequency regulating device comprises a charging pile and an energy storage converter, the frequency interval in which the droop control curve acts is determined to be the second interval; wherein the difference between the rated frequency and the second preset threshold value is a first boundary point of the second interval, and the difference between the rated frequency and the first preset threshold value is a second boundary point of the second interval.

[0149] In a possible implementation, the preset curve expression is a quadratic polynomial curve, and the parameters to be solved comprise a quadratic term coefficient, a linear term coefficient, and a constant term; and the second processing unit 73 is specifically configured to: according to the power output values of the target frequency regulating device at the first boundary point, the second boundary point, and the median point of the frequency interval, solve the preset curve expression to determine the value of the quadratic term coefficient, the value of the linear term coefficient, and the value of the constant term in the preset curve expression.

[0150] The droop control curve of the target frequency regulating device is obtained according to the value of the quadratic term coefficient, the value of the linear term coefficient, and the value of the constant term in the preset curve expression.

[0151] In a possible implementation, after the third processing unit 74, the apparatus 7 further comprises a monitoring unit, configured to:

[0152] monitor the frequency of the power system.

[0153] If the absolute value of the difference between the frequency of the power system and the rated frequency is less than the first preset threshold value, it is determined that the frequency of the power system is in a stable state, and the output power of the target frequency regulating device is controlled to return to the output power before frequency regulation.

[0154] In a possible implementation, after the monitoring unit, the apparatus 7 further comprises an optimization unit, specifically configured to:

[0155] According to The evaluation index of the joint frequency modulation is calculated.

[0156] Q f is an evaluation index, T is a time interval, t over is a time when the absolute value of the difference between the power system frequency and the rated frequency exceeds a first preset threshold in the time period T, f N is a rated frequency, Δf over is a deviation when the absolute value of the difference between the power system frequency and the rated frequency exceeds the first preset threshold, f over is a frequency value when the absolute value of the difference between the power system frequency and the rated frequency exceeds the first preset threshold, Δf is the first preset threshold.

[0157] Based on the evaluation index, the expected frequency modulation speed information is adjusted.

[0158] In one possible implementation, after the obtaining unit 71, the device 7 further includes a fourth processing unit, configured to:

[0159] If the power system frequency is not in the frequency modulation action interval, the absolute value of the difference between the power system frequency and the rated frequency is determined.

[0160] If the absolute value of the difference is less than the first preset threshold, it is indicated that the new energy frequency modulation flexible aggregate maintains the current working state.

[0161] If the absolute value of the difference is greater than the second preset threshold, it is determined that the power system has a fault, and fault prompt information is output.

[0162] In the above embodiments, the description of each embodiment has its own focus, and the parts not described or recorded in detail in a certain embodiment can be referred to the related description of other embodiments.

[0163] Those of ordinary skill in the art can realize that the templates, units and algorithm steps of each example described in combination with the embodiments disclosed herein can be realized by electronic hardware or a combination of computer software and electronic hardware. Whether the functions are executed in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0164] The modules / units, if implemented in the form of software functional units and sold or used as independent products, can be stored in a computer readable storage medium. Based on such understanding, all or part of the processes in the above-mentioned embodiments of the method of the present application can also be completed by a computer program instructing related hardware, and the computer program can be stored in a computer readable storage medium. When the computer program is executed by a processor, the steps of each embodiment of the above-mentioned auxiliary frequency modulation method based on new energy frequency modulation flexible aggregation can be implemented. The computer program includes computer program code, which can be in the form of source code, object code, executable files or some intermediate forms, etc. The computer readable medium can include any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory, random access memory, electrical carrier signal, telecommunication signal and software distribution medium, etc.

[0165] The above embodiments are only used to illustrate the technical solutions of the present application, but not limit it; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.

Claims

1. An auxiliary frequency modulation method based on a new energy frequency modulation flexible polymer, characterized in that, The method includes: Obtain the power system frequency and determine whether the power system frequency is within the frequency regulation range; If the power system frequency is within the frequency regulation operation range, the target frequency regulation device in the new energy frequency regulation flexible aggregate is determined based on the difference between the power system frequency and the rated frequency; wherein, the new energy frequency regulation flexible aggregate includes photovoltaic inverters, energy storage converters and charging piles, and the target frequency regulation device is one or more devices in the new energy frequency regulation flexible aggregate; Based on the preset desired frequency regulation speed information, the droop control curve of the target frequency regulation device is obtained; wherein, the droop control curve is used to indicate the correspondence between the output frequency of the target frequency regulation device and the power system frequency, and the desired frequency regulation speed information is used to indicate the slope of the droop control curve corresponding to the target frequency regulation device; based on the droop control curve, the output power of the target frequency regulation device is adjusted to assist the thermal power unit in regulating the frequency of the power system and maintaining the frequency stability of the power system.

2. The auxiliary frequency modulation method based on a new energy frequency modulation flexible polymer according to claim 1, characterized in that, The step of obtaining the droop control curve of the target frequency modulation device based on preset desired frequency modulation speed information includes: Obtain the frequency range in which the droop control curve operates; Based on the desired frequency modulation speed information, the power output values ​​of the target frequency modulation device at the boundary points and median points of the frequency range are determined; Obtain a preset curve expression; wherein, the preset curve expression includes parameters to be solved; Based on the power output values ​​of the target frequency modulation device at the boundary points and median points of the frequency range, the values ​​of the parameters to be solved in the preset curve expression are determined, and based on the values ​​of the parameters to be solved, the droop control curve of the target frequency modulation device is obtained; wherein, the droop control curve is used to indicate the correspondence between the output frequency of the target frequency modulation device and the power system frequency within the frequency range.

3. The auxiliary frequency modulation method based on a new energy frequency modulation flexible polymer according to claim 2, characterized in that, The step of determining the target frequency regulation equipment in the new energy frequency regulation flexible aggregate based on the difference between the power system frequency and the rated frequency includes: If the difference is positive, then the target frequency modulation device is determined to include a photovoltaic inverter and an energy storage converter, and the working state of the energy storage converter is controlled to be a charging state. If the difference is negative, then the target frequency modulation device is determined to include a charging pile and an energy storage converter, and the working state of the energy storage converter is controlled to be a discharge state.

4. The auxiliary frequency modulation method based on a new energy frequency modulation flexible polymer according to claim 3, characterized in that, The frequency modulation operation range includes a first range and a second range; The process of obtaining the frequency range of the droop control curve includes: If the target frequency regulation device includes a photovoltaic inverter and an energy storage converter, then the frequency range in which the droop control curve acts is determined to be the first range; wherein, the sum of the rated frequency of the power system and a first preset threshold is the first boundary point of the first range, and the sum of the rated frequency and a second preset threshold is the second boundary point of the first range; the second preset threshold is greater than the first preset threshold. If the target frequency regulation device includes a charging pile and an energy storage converter, then the frequency range in which the droop control curve acts is determined to be the second range; wherein, the difference between the rated frequency and the second preset threshold is the first boundary point of the second range, and the difference between the rated frequency and the first preset threshold is the second boundary point of the second range.

5. The auxiliary frequency modulation method based on a new energy frequency modulation flexible polymer according to claim 4, characterized in that, The preset curve expression is a quadratic polynomial curve, and the parameters to be solved include the coefficients of the quadratic term, the coefficients of the linear term, and the constant term. The step of determining the values ​​of the parameters to be solved in the preset curve expression based on the power output values ​​of the target frequency modulation device at the boundary points and median points of the frequency range, and obtaining the droop control curve of the target frequency modulation device based on the values ​​of the parameters to be solved, includes: Based on the power output values ​​of the target frequency modulation device at the first boundary point, the second boundary point, and the median point of the frequency range, the preset curve expression is solved to determine the values ​​of the quadratic coefficient, the linear coefficient, and the constant term in the preset curve expression. Based on the values ​​of the quadratic coefficient, the linear coefficient, and the constant term in the preset curve expression, the droop control curve of the target frequency modulation device is obtained.

6. The auxiliary frequency modulation method based on a new energy frequency modulation flexible polymer according to any one of claims 1-5, characterized in that, After adjusting the output power of the target frequency modulation device based on the droop control curve to assist the thermal power unit in regulating the frequency of the power system, the method further includes: Monitor power system frequencies; If the absolute value of the difference between the power system frequency and the rated frequency is less than the first preset threshold, the power system frequency is determined to be in a stable state, and the output power of the target frequency modulation device is controlled to be restored to the output power before frequency modulation.

7. The auxiliary frequency modulation method based on a new energy frequency modulation flexible polymer according to claim 6, characterized in that, After determining that the power system frequency is in a stable state, the method further includes: according to The evaluation indexes for joint frequency modulation were calculated. Among them, Q f Let t be the evaluation index, T be the time interval, and t be the time period. over f is the time during which the absolute value of the difference between the power system frequency and the rated frequency exceeds the first preset threshold within the time period T. N For the rated frequency, Δf over f is the deviation where the absolute value of the difference between the power system frequency and the rated frequency exceeds the first preset threshold. over The frequency value at which the absolute value of the difference between the power system frequency and the rated frequency exceeds the first preset threshold. Δf is the first preset threshold; Based on the evaluation indicators, the desired frequency modulation speed information is adjusted.

8. The auxiliary frequency modulation method based on a new energy frequency modulation flexible polymer according to any one of claims 1-5, characterized in that, After acquiring the power system frequency and determining whether the power system frequency is within the frequency regulation operation range, the method further includes: If the power system frequency is not within the frequency regulation range, then determine the absolute value of the difference between the power system frequency and the rated frequency; If the absolute value of the difference is less than the first preset threshold, the new energy frequency-modulated flexible polymer is instructed to maintain its current working state. If the absolute value of the difference is greater than the second preset threshold, a fault is determined to have occurred in the power system, and a fault prompt message is output.

9. An auxiliary frequency modulation device based on a new energy frequency modulation flexible polymer, characterized in that, The device includes: The acquisition unit is used to acquire the power system frequency and determine whether the power system frequency is within the frequency regulation range. The first processing unit is configured to determine the target frequency regulation device in the new energy frequency regulation flexible aggregate based on the difference between the power system frequency and the rated frequency if the power system frequency is within the frequency regulation operation range; wherein the new energy frequency regulation flexible aggregate includes photovoltaic inverters, energy storage converters and charging piles, and the target frequency regulation device is one or more devices in the new energy frequency regulation flexible aggregate. The second processing unit is used to obtain the droop control curve of the target frequency modulation device based on the preset desired frequency modulation speed information; wherein, the droop control curve is used to indicate the correspondence between the output frequency of the target frequency modulation device and the power system frequency, and the desired frequency modulation speed information is used to indicate the slope of the droop control curve corresponding to the target frequency modulation device. The third processing unit is used to adjust the output power of the target frequency modulation device based on the droop control curve, so as to assist the thermal power unit in regulating the frequency of the power system and maintaining the frequency stability of the power system.

10. The auxiliary frequency modulation device based on a new energy frequency modulation flexible polymer according to claim 9, characterized in that, The second processing unit is specifically used for: Obtain the frequency range in which the droop control curve operates; Based on the desired frequency modulation speed information, the power output values ​​of the target frequency modulation device at the boundary points and median points of the frequency range are determined; Obtain a preset curve expression; wherein, the preset curve expression includes parameters to be solved; Based on the power output values ​​of the target frequency modulation device at the boundary points and median points of the frequency range, the values ​​of the parameters to be solved in the preset curve expression are determined, and based on the values ​​of the parameters to be solved, the droop control curve of the target frequency modulation device is obtained; wherein, the droop control curve is used to indicate the correspondence between the output frequency of the target frequency modulation device and the power system frequency within the frequency range.

Images