Power plant and energy storage system combined frequency modulation intelligent control method

Abstract

The invention relates to the technical field of electric power control, and discloses a power plant and energy storage system combined frequency modulation intelligent control method, which comprises the following steps: monitoring the power grid frequency in real time, and constructing a power grid frequency curve according to the power grid frequency obtained through real-time monitoring in a monitoring period to obtain an over-bounded area and a non-over-bounded area; analyzing and processing the over-bounded region and the non-over-bounded region, obtaining power grid frequency dynamic data, obtaining a power grid frequency behavior value based on the power grid frequency dynamic data, and completing the state recognition of the power system; based on the abnormal operation signal of the power system, processing the rotating speed of the motor in the over-bounded region and the non-over-bounded region corresponding to the power grid frequency to obtain a rotating speed signal of the motor of the power grid frequency over-bounded region and the power plant; the rotating speed signal comprises a rotating speed non-interference signal and a rotating speed interference signal; and based on the rotating speed interference signal, taking the non-out-of-limit area as a reference, performing combined frequency modulation control on the power plant and the energy storage system in the out-of-limit area, and realizing visual maintenance management of the power system.

Description

Technical Field

[0001] The present invention relates to the technical field of power control, and in particular to an intelligent control method for combined frequency regulation of a power plant and an energy storage system. Background Art

[0002] With the rapid development of new energy and the rapid growth of installed capacity, the high proportion of new energy access has brought challenges to the power grid. The volatility and uncertainty of new energy have increased the probability of grid frequency fluctuations, posing a threat to the stable operation of the power system.

[0003] Based on this, the intelligent control of the joint frequency regulation of power plants and energy storage systems is particularly important. Through the application of energy storage systems and intelligent control technologies, stable control of the grid frequency can be achieved, improving the stability of the grid and energy utilization efficiency.

[0004] Since the stability of the grid frequency directly affects the stability of the power system and the operating efficiency of the power equipment, the existing technology lacks monitoring of the grid frequency status in terms of grid stability and energy utilization efficiency, and cannot identify the power system status in a timely and effective manner, which has certain limitations. Summary of the invention

[0005] The purpose of the present invention is to provide an intelligent control method for the joint frequency regulation of a power plant and an energy storage system, to monitor the grid frequency in real time during a monitoring period, to construct a grid frequency curve, and to analyze and process the out-of-bounds area or the non-out-of-bounds area in the grid frequency curve, that is, by obtaining the frequency out-of-bounds ratio, frequency asymmetry ratio and peak-to-valley deviation ratio of the grid frequency during the monitoring period, the grid frequency behavior value of the power system is obtained, and the operating status of the power system is identified based on the grid frequency behavior value of the power system, so as to realize visual maintenance and management of the power system.

[0006] The purpose of the present invention can be achieved by the following technical solutions: A method for intelligent frequency regulation control of a power plant and an energy storage system, comprising the following steps: The grid frequency is monitored in real time. During the monitoring period, a grid frequency curve is constructed according to the grid frequency obtained by real-time monitoring to obtain the over-boundary area and the non-over-boundary area. Analyze and process the over-boundary area and the non-over-boundary area, obtain the dynamic data of the power grid frequency, obtain the power grid frequency behavior value based on the dynamic data of the power grid frequency, and complete the identification of the power system status; Based on the abnormal operation signal of the power system, the motor speed in the over-limit area and the non-over-limit area corresponding to the power grid frequency is processed to obtain the speed signal of the motor of the power plant when the power grid frequency is over-limit; The speed signal includes a speed non-interference signal and a speed interference signal; Based on the speed interference signal, the power plant and energy storage system in the out-of-bounds area are jointly controlled for frequency regulation with the non-out-of-bounds area as the benchmark.

[0007] As a further solution of the present invention: the power grid frequency acquired in real time is plotted in a plane coordinate system to construct a power grid frequency curve; Obtaining a rated range value of the power grid frequency, and recording an upper limit value of the rated range value of the power grid frequency as a first standard value; Recording the lower limit of the rated range of the power grid frequency as the second standard value; Draw a horizontal line parallel to the X-axis in the plane coordinate system for the first standard value, which is recorded as the first frequency standard line; Draw a horizontal line parallel to the X-axis in the plane coordinate system for the second standard value, which is recorded as the second frequency standard line.

[0008] As a further solution of the present invention: the area enclosed by the curve of the power grid frequency curve located above the first frequency standard line is recorded as the first over-boundary area; The area enclosed by the curve of the power grid frequency curve below the second frequency standard line is recorded as the second over-boundary area; The first over-boundary region and the second over-boundary region are collectively recorded as an over-boundary region; The area where the grid frequency region is located between the first frequency standard line and the second frequency standard line is recorded as the non-over-boundary area.

[0009] As a further solution of the present invention: the power grid frequency dynamic data includes frequency over-range ratio, frequency asymmetry ratio and peak-to-valley deviation ratio; The frequency excess ratio is recorded as Pw; The frequency asymmetry ratio is denoted as Py; The peak-to-valley deviation ratio is recorded as Pf; By formula The grid frequency behavior value Pi of the power system is obtained, wherein a1, a2, and a3 are all preset proportional coefficients.

[0010] As a further solution of the present invention: the first limit value of the grid frequency behavior value is preset to be Pi1, and the second limit value is preset to be Pi2, wherein Pi1<Pi2; If Pi<Pi1, it means that the grid frequency is operating well during the monitoring period, and a signal that the power system is operating well is obtained; If Pi1≤Pi<Pi2, it means that the grid frequency is operating normally within the monitoring period, and a signal that the power system is operating normally is obtained; If Pi ≥ Pi2, it means that the grid frequency is operating abnormally during the monitoring period, and an abnormal power system operation signal is obtained.

[0011] As a further solution of the present invention: the frequency over-bound ratio is calculated as the ratio of the area value of the over-bound region to the area value of the non-over-bound region; The ratio of the total duration of the frequency asymmetry ratio out-of-bounds area to the total duration of the monitoring period; The maximum peak values ​​of the plurality of first out-of-bounds regions are summed and averaged to obtain a peak deviation value of the first out-of-bounds region; Calculate the ratio of the peak deviation value of the first over-boundary region to the first standard value to obtain a peak deviation ratio; The maximum trough values ​​of the plurality of second over-boundary regions are summed and averaged to obtain the trough deviation value of the second over-boundary region; The second standard value is calculated by difference with the valley deviation value to obtain the valley deviation; The valley deviation is calculated by ratioing the valley deviation with the second standard value to obtain the valley deviation ratio; The peak deviation ratio is calculated by multiplying the peak deviation ratio by the valley deviation ratio to obtain the peak-to-valley deviation ratio.

[0012] As a further solution of the present invention: the non-overstepping area is divided into a plurality of in-bounds time sub-units according to the time length; Obtain the grid frequency value at the middle moment of each intra-boundary time subunit and the motor speed of the power plant corresponding to the grid frequency value; The motor speed of the power plant in each time sub-unit within the boundary is processed by the difference between the motor rated speed and the motor to obtain the internal speed deviation state value of the time sub-unit within the boundary; Divide the out-of-bounds area into a number of out-of-bounds time sub-units according to the length of time; Obtain the grid frequency value at the middle moment of each out-of-bounds time subunit and the motor speed of the power plant corresponding to the grid frequency value; The motor speed of the power plant in each out-of-bounds time subunit is processed with the motor rated speed to obtain the out-of-bounds speed deviation state value of the out-of-bounds time subunit.

[0013] As a further solution of the present invention: the inner speed deviation state value of the inner time subunit is calculated by difference with the outer speed deviation state value of the outer time subunit to obtain the inner and outer speed abnormal value; If the speed fluctuation value inside and outside the boundary is within the preset speed fluctuation value range inside and outside the boundary, it means that the abnormality of the power grid frequency has nothing to do with the motor speed of the power plant, and a speed interference-free signal is obtained; If the speed variation value inside and outside the boundary is outside the preset speed variation value range inside and outside the boundary, it means that the abnormal frequency of the power grid is related to the motor speed of the power plant, and a speed interference signal is obtained.

[0014] As a further solution of the present invention: a plane coordinate system is established, with the number of time subunits within the boundary as the X-axis and the motor speed or the power of the power plant as the Y-axis; The motor speed corresponding to the time sub-unit within the boundary is plotted in order from large to small, and all the points corresponding to the motor speed are connected from left to right with a smooth curve to obtain a motor speed curve, and then the power plant electricity corresponding to the motor speed of each time sub-unit within the boundary is plotted in the coordinate system to obtain a power plant electricity curve; Identify the power curve of the power plant and obtain the correlation signal between the motor speed and power generation; Correlation signals include positive correlation signals and negative correlation signals.

[0015] As a further solution of the present invention: if the power curve of the power plant is not correlated with the changing trend of the motor speed curve, the power interval value of the out-of-bounds area and the power interval value of the non-out-of-bounds area are processed to complete the correlation processing of the power generation and the energy storage system.

[0016] Beneficial effects of the present invention: (1) The present invention monitors the power grid frequency in real time within a monitoring period, constructs a power grid frequency curve, and analyzes and processes the over-boundary area or the non-over-boundary area in the power grid frequency curve, that is, by obtaining the frequency over-boundary ratio, frequency asymmetry ratio and peak-to-valley deviation ratio of the power grid frequency within the monitoring period, the power grid frequency behavior value of the power system is obtained, and the power system operation status is identified based on the power grid frequency behavior value of the power system, thereby realizing visual maintenance and management of the power system; (2) When the power system generates an abnormal operation signal, the present invention obtains the inner speed deviation state value corresponding to the non-out-of-bounds area in the power grid frequency and the outer speed deviation state value corresponding to the out-of-bounds area, processes the inner speed deviation state value of the in-bounds time subunit and the outer speed deviation state value of the out-of-bounds time subunit to obtain the inner and outer speed difference values, and completes the correlation analysis between the power grid frequency anomaly and the motor speed based on the inner and outer speed difference values, so as to facilitate the joint frequency regulation control of the power plant and the energy storage system when the motor speed of the subsequent power plant is abnormal. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be further described below in conjunction with the accompanying drawings.

[0018] Figure 1 It is a flow chart of an intelligent control method for combined frequency regulation of a power plant and an energy storage system according to the present invention; Figure 2 It is a flow chart of power system state identification in a power plant and energy storage system joint frequency regulation intelligent control method of the present invention; Figure 3 The invention discloses a flow chart of speed interference signal identification in a method for intelligent frequency modulation of a power plant and an energy storage system. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] Example 1, please refer to Figure 1 As shown, the present invention is a method for intelligent frequency regulation control of a power plant and an energy storage system, comprising the following steps: The grid frequency is monitored in real time. During the monitoring period, a grid frequency curve is constructed according to the grid frequency obtained by real-time monitoring to obtain the over-boundary area and the non-over-boundary area. Analyze and process the over-boundary area and the non-over-boundary area, obtain the dynamic data of the power grid frequency, obtain the power grid frequency behavior value based on the dynamic data of the power grid frequency, and complete the identification of the power system status; Based on the abnormal operation signal of the power system, the motor speed in the over-limit area and the non-over-limit area corresponding to the power grid frequency is processed to obtain the speed signal of the motor of the power plant when the power grid frequency is over-limit; The speed signal includes a speed non-interference signal and a speed interference signal; Based on the speed interference signal, the power plant and energy storage system in the out-of-bounds area are jointly controlled for frequency regulation with the non-out-of-bounds area as the benchmark.

[0021] Embodiment 2, the analysis process of the power grid frequency curve is as follows: Specific: A plane coordinate system is established with time as the X-axis and the real-time grid frequency as the Y-axis; The power grid frequency acquired in real time is plotted in a plane coordinate system to construct a power grid frequency curve; Obtaining a rated range value of the power grid frequency, and recording an upper limit value of the rated range value of the power grid frequency as a first standard value; Recording the lower limit of the rated range of the power grid frequency as the second standard value; Draw a horizontal line parallel to the X-axis in the plane coordinate system for the first standard value, which is recorded as the first frequency standard line; Draw a horizontal line parallel to the X-axis in the plane coordinate system for the second standard value, which is recorded as the second frequency standard line.

[0022] Perform regional analysis on the first frequency standard line, the second frequency standard line and the power grid frequency curve within the monitoring period, specifically: The area enclosed by the curve of the power grid frequency curve located above the first frequency standard line is recorded as the first over-boundary area; The area enclosed by the curve of the power grid frequency curve below the second frequency standard line is recorded as the second over-boundary area; The first over-boundary region and the second over-boundary region are collectively recorded as an over-boundary region; The area where the grid frequency region is located between the first frequency standard line and the second frequency standard line is recorded as the non-over-boundary area.

[0023] Process the out-of-bounds and non-out-of-bounds areas, identify the operating status of the power grid frequency, and complete the stability assessment of the power system; Obtaining the area value of the over-boundary region and the area value of the non-over-boundary region, calculating the ratio of the area value of the over-boundary region to the area value of the non-over-boundary region, and obtaining the frequency over-boundary ratio; Obtain the total duration of the out-of-bounds area and the total duration of the monitoring period, calculate the ratio of the total duration of the out-of-bounds area to the total duration of the monitoring period, and obtain the frequency asymmetry ratio; Process each independent first out-of-bounds region to obtain the maximum peak value in each independent first out-of-bounds region; The maximum peak values ​​of the plurality of first out-of-bounds regions are summed and averaged to obtain a peak deviation value of the first out-of-bounds region; Calculate the ratio of the peak deviation value of the first over-boundary region to the first standard value to obtain a peak deviation ratio; Process each independent second out-of-bounds region to obtain the maximum trough value in each independent second out-of-bounds region; The maximum trough values ​​of the plurality of second over-boundary regions are summed and averaged to obtain the trough deviation value of the second over-boundary region; The difference between the second standard value and the valley deviation value is calculated to obtain the valley deviation; The valley deviation is calculated by ratioing the valley deviation with the second standard value to obtain the valley deviation ratio; The peak deviation ratio is calculated by multiplying the peak deviation ratio and the valley deviation ratio to obtain the peak-to-valley deviation ratio; The frequency excess ratio is recorded as Pw; The frequency asymmetry ratio is denoted as Py; The peak-to-valley deviation ratio is recorded as Pf; By formula Obtain the grid frequency behavior value Pi of the power system, wherein a1, a2, and a3 are all preset proportional coefficients, and a1, a2, and a3 are all greater than zero; It can be seen from the above formula for obtaining the grid frequency behavior value of the power system that, within the monitoring period, the larger the area enclosed by the first over-boundary area and the second over-boundary area, the greater the magnitude by which the grid frequency exceeds the rated range value of the grid frequency, the greater the obtained frequency over-range ratio, the greater the grid frequency behavior value, and the worse the grid frequency state; During the monitoring period, the longer the first and second out-of-bounds areas last, the greater the proportion of time that the grid frequency exceeds the rated range of the grid frequency, the greater the obtained frequency asymmetry ratio, the greater the grid frequency behavior value, and the worse the grid frequency state; During the monitoring period, the greater the peak deviation ratio of the first out-of-bounds area and the valley deviation ratio of the second out-of-bounds area, the greater the deviation between the grid frequency and the rated range value of the grid frequency, the greater the peak-to-valley deviation ratio obtained, the greater the grid frequency behavior value, and the worse the grid frequency state.

[0024] See also Figure 2 , the first limit value of the preset grid frequency behavior value is Pi1, and the second limit value is Pi2, wherein Pi1<Pi2; Among them, the first limit value Pi1 and the second limit value Pi2 of the grid frequency behavior value are empirical values, which are obtained based on experience: In the actual obtaining process, there are many groups of frequency over-range ratios, frequency asymmetry ratios and peak-to-valley deviation ratios. Many groups of frequency over-range ratios, frequency asymmetry ratios and peak-to-valley deviation ratios are processed to obtain the grid frequency behavior values ​​of the corresponding groups. The staff identifies the power system status level according to so many groups of grid frequency behavior values, thereby obtaining a corresponding relationship between a grid frequency behavior value and the power system status level, and then derives and divides the grid frequency behavior value according to the power system status level of the grid frequency behavior value, thereby obtaining the first limit value Pi1 and the second limit value Pi2 of the grid frequency behavior value, and completes the identification of the power system status level corresponding to the grid frequency behavior value by comparing the limit values ​​of the grid frequency behavior value; If Pi<Pi1, it means that the grid frequency is operating well during the monitoring period, and a signal that the power system is operating well is obtained; If Pi1≤Pi<Pi2, it means that the grid frequency is operating normally within the monitoring period, and a signal that the power system is operating normally is obtained; If Pi ≥ Pi2, it means that the grid frequency is operating abnormally during the monitoring period, and an abnormal power system operation signal is obtained.

[0025] Therefore, according to the changes in the grid frequency during the monitoring period, the operating status of the power system can be identified, and visual maintenance and management of the power system can be achieved; The monitoring period includes but is not limited to 1 day, 10 days or 30 days.

[0026] Embodiment 3, based on the power plant and energy storage system states corresponding to the grid frequency in the non-over-boundary area, the power plant and energy storage system in the over-boundary area are jointly frequency-controlled; Specific: Obtaining the non-overstepping area, and dividing the non-overstepping area into a number of in-bounds time sub-units according to the time length; Respectively obtain the grid frequency value at the middle moment of each intra-boundary time subunit; Get the motor speed of the power plant corresponding to the grid frequency value; The difference between the motor speed of the power plant and the rated speed of the motor in each time sub-unit within the boundary is calculated and the absolute value is taken to obtain the internal speed deviation value of the time sub-unit within the boundary; The internal speed deviation values ​​of all the internal time sub-units are summed and averaged to obtain the internal speed deviation state value of the internal time sub-unit; Obtaining the out-of-bounds region, and dividing the out-of-bounds region into a number of out-of-bounds time sub-units according to the time length; Respectively obtain the grid frequency value at the middle moment of each out-of-bounds time subunit; Get the motor speed of the power plant corresponding to the grid frequency value; The motor speed of the power plant in each out-of-bounds time sub-unit is calculated to be different from the rated speed of the motor and the absolute value is taken to obtain the out-of-bounds speed deviation value of the out-of-bounds time sub-unit; The external speed deviation values ​​of all out-of-bounds time sub-units are summed and averaged to obtain the external speed deviation state value of the out-of-bounds time sub-unit; The difference between the inner speed deviation state value of the inner time subunit and the outer speed deviation state value of the outer time subunit is calculated to obtain the inner and outer speed deviation values; See also Figure 3 If the speed fluctuation value inside and outside the boundary is within the preset speed fluctuation value range, it means that the abnormality of the power grid frequency has nothing to do with the motor speed of the power plant, and a speed interference-free signal is obtained; If the speed variation value inside and outside the boundary is outside the preset speed variation value range inside and outside the boundary, it means that the abnormal frequency of the power grid is related to the motor speed of the power plant, and a speed interference signal is obtained.

[0027] Embodiment 4, based on the speed interference signal, obtain the motor speed of the power plant corresponding to all the time sub-units within the boundary area; Establish a plane coordinate system, with the number of time sub-units within the boundary as the X-axis and the motor speed or power generation of the power plant as the Y-axis; In the plane coordinate system, the motor speed corresponding to the time sub-unit within the boundary is plotted in order from large to small, and all the points corresponding to the motor speed are connected from left to right with a smooth curve to obtain the motor speed curve; Then, the power of the power plant corresponding to the motor speed of each time sub-unit within the boundary is plotted in the coordinate system, and all the points corresponding to the power of the power plant are connected from left to right with a smooth curve to obtain the power curve of the power plant; Identify the power curve of the power plant; If the power plant's electricity curve and the motor speed curve have the same changing trend, both changing linearly and tilting downward, it means that the lower the motor speed, the lower the power plant's electricity generation, generating a positive correlation signal; Based on the positive correlation signal, the motor speed in the out-of-bounds area is identified. If the motor speed in the out-of-bounds area exceeds the rated speed of the motor, the energy storage system is discharged, so that the energy storage system provides a certain amount of power to the power system to avoid heating caused by the motor speed process. Based on the positive correlation signal, the motor speed in the out-of-bounds area is identified. If the motor speed in the out-of-bounds area exceeds the rated speed of the motor, the energy storage system is charged to store the excess power in the power system, thus avoiding the waste of power in the power plant. Based on the positive correlation signal, the motor speed in the out-of-bounds area is identified. If the motor speed in the out-of-bounds area does not exceed the rated speed of the motor, the energy storage system is discharged to provide power to the power system to ensure the stability of the power system.

[0028] If the power plant's electricity curve and the motor speed curve have opposite trends, both changing linearly and tilting upward, it means that the lower the motor speed, the higher the power plant's electricity output, generating a negative correlation signal; Based on the negative correlation signal, the motor speed in the out-of-bounds area is identified. If the motor speed in the out-of-bounds area exceeds the rated speed of the motor, the energy storage system is discharged, so that the energy storage system provides power to the power system to ensure the stability of the power system. Based on the negative correlation signal, the motor speed in the out-of-bounds area is identified. If the motor speed in the out-of-bounds area does not exceed the rated speed of the motor, the energy storage system is charged to store the excess power in the power system to avoid wasting power in the power plant.

[0029] If the power curve of the power plant has no correlation with the change trend of the motor speed curve and is in a nonlinear wave shape, obtain the motor speed corresponding to the maximum power value in the power curve of the power plant, and record it as the first speed; Obtain the motor speed corresponding to the minimum value of the power in the power curve of the power plant, and record it as the second speed; The maximum value of the electric quantity and the minimum value of the electric quantity are calculated to obtain the electric quantity deviation; Calculate the difference between the first speed and the second speed to obtain a speed deviation; Calculate the ratio of the power deviation to the speed deviation to obtain the speed factor; Obtain the maximum motor speed and the minimum motor speed in the out-of-bounds area, multiply the speed factor by the maximum motor speed to obtain the maximum power value in the out-of-bounds area; The minimum power value in the out-of-bounds area is obtained by multiplying the speed factor by the minimum motor speed. Get the power interval value of the out-of-bounds area; Overlap the power interval value of the out-of-bounds area with the power interval value of the non-out-of-bounds area; If the power interval value of the out-of-bounds area does not overlap with the power interval value of the non-out-of-bounds area; That is, if the power interval value of the out-of-bounds area is smaller than the power interval value of the non-out-of-bounds area, the energy storage system will discharge, so that the energy storage system can provide power to the power system to ensure the stability of the power system. That is, if the power interval value of the over-boundary area is greater than the power interval value of the non-over-boundary area, the energy storage system will be charged to store the excess power in the power system to avoid power waste in the power plant; If the power interval value of the out-of-bounds area overlaps with the power interval value of the non-out-of-bounds area; The speed range of the overlapped area is obtained, and the power generation of the power plant corresponding to the out-of-bounds area within the speed range and the energy storage system are processed according to the corresponding positive correlation signal or negative correlation signal.

[0030] One of the core points of the present invention is to monitor the grid frequency in real time during the monitoring period, construct a grid frequency curve, and analyze and process the out-of-bounds area or the non-out-of-bounds area in the grid frequency curve, that is, by obtaining the frequency out-of-bounds ratio, frequency asymmetry ratio and peak-to-valley deviation ratio of the grid frequency during the monitoring period, the grid frequency behavior value of the power system is obtained, and the operating status of the power system is identified based on the grid frequency behavior value of the power system, thereby realizing visual maintenance and management of the power system.

[0031] One of the core points of the present invention is that when an abnormal signal is generated during the operation of the power system, an inner speed deviation state value corresponding to a non-out-of-bounds area in the power grid frequency and an outer speed deviation state value corresponding to an out-of-bounds area are obtained, and the inner speed deviation state value of the in-bounds time subunit and the outer speed deviation state value of the out-of-bounds time subunit are processed to obtain inner and outer speed variation values, and based on the inner and outer speed variation values, a correlation analysis between the abnormal power grid frequency and the motor speed is completed, so as to facilitate the joint frequency regulation control of the power plant and the energy storage system when the motor speed of the subsequent power plant is abnormal.

[0032] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A method for intelligent frequency regulation control of a power plant and an energy storage system, characterized in that: The following steps are involved: The grid frequency is monitored in real time. During the monitoring period, a grid frequency curve is constructed according to the grid frequency obtained by real-time monitoring to obtain the over-boundary area and the non-over-boundary area. Analyze and process the over-boundary area and the non-over-boundary area, obtain the dynamic data of the power grid frequency, obtain the power grid frequency behavior value based on the dynamic data of the power grid frequency, and complete the identification of the power system status; Based on the abnormal operation signal of the power system, the motor speed in the over-limit area and the non-over-limit area corresponding to the power grid frequency is processed to obtain the speed signal of the motor of the power plant when the power grid frequency is over-limit; The speed signal includes a speed non-interference signal and a speed interference signal; Based on the speed interference signal, the power plant and energy storage system in the out-of-bounds area are jointly controlled for frequency regulation with the non-out-of-bounds area as the benchmark.

2. According to claim 1, a power plant and energy storage system combined frequency modulation intelligent control method is characterized in that: The power grid frequency acquired in real time is plotted in a plane coordinate system to construct a power grid frequency curve; Obtaining a rated range value of the power grid frequency, and recording an upper limit value of the rated range value of the power grid frequency as a first standard value; Recording the lower limit of the rated range of the power grid frequency as the second standard value; Draw a horizontal line parallel to the X-axis in the plane coordinate system for the first standard value, which is recorded as the first frequency standard line; Draw a horizontal line parallel to the X-axis in the plane coordinate system for the second standard value, which is recorded as the second frequency standard line.

3. According to claim 2, a method for intelligent frequency regulation control of a power plant and an energy storage system is characterized in that: The area enclosed by the curve of the power grid frequency curve located above the first frequency standard line is recorded as the first over-boundary area; The area enclosed by the curve of the power grid frequency curve below the second frequency standard line is recorded as the second over-boundary area; The first over-boundary region and the second over-boundary region are collectively recorded as an over-boundary region; The area where the grid frequency region is located between the first frequency standard line and the second frequency standard line is recorded as the non-over-boundary area.

4. The method for intelligent frequency regulation control of a power plant and an energy storage system according to claim 1 is characterized in that: The power grid frequency dynamic data includes frequency over-range ratio, frequency asymmetry ratio and peak-to-valley deviation ratio; The frequency excess ratio is recorded as Pw; The frequency asymmetry ratio is denoted as Py; The peak-to-valley deviation ratio is recorded as Pf; By formula The grid frequency behavior value Pi of the power system is obtained, wherein a1, a2, and a3 are all preset proportional coefficients.

5. The method for intelligent frequency regulation of a power plant and an energy storage system according to claim 4 is characterized in that: The first limit value of the preset grid frequency behavior value is Pi1, and the second limit value is Pi2, wherein Pi1<Pi2; If Pi<Pi1, it means that the grid frequency is operating well during the monitoring period, and a signal that the power system is operating well is obtained; If Pi1≤Pi<Pi2, it means that the grid frequency is operating normally within the monitoring period, and a signal that the power system is operating normally is obtained; If Pi ≥ Pi2, it means that the grid frequency is operating abnormally during the monitoring period, and an abnormal power system operation signal is obtained.

6. The method for intelligent frequency regulation control of a power plant and an energy storage system according to claim 4 is characterized in that: The frequency over-bound ratio is calculated as the ratio of the area value of the over-bound region to the area value of the non-over-bound region; The ratio of the total duration of the frequency asymmetry ratio out-of-bounds area to the total duration of the monitoring period; The maximum peak values ​​of the plurality of first out-of-bounds regions are summed and averaged to obtain a peak deviation value of the first out-of-bounds region; Calculate the ratio of the peak deviation value of the first over-boundary region to the first standard value to obtain a peak deviation ratio; The maximum trough values ​​of the plurality of second over-boundary regions are summed and averaged to obtain the trough deviation value of the second over-boundary region; The difference between the second standard value and the valley deviation value is calculated to obtain the valley deviation; The valley deviation is calculated by ratioing the valley deviation with the second standard value to obtain the valley deviation ratio; The peak deviation ratio is calculated by multiplying the peak deviation ratio by the valley deviation ratio to obtain the peak-to-valley deviation ratio.

7. The method for intelligent frequency regulation control of a power plant and an energy storage system according to claim 1 is characterized in that: Divide the non-overstepping area into a number of in-bounds time sub-units according to the length of time; Obtain the grid frequency value at the middle moment of each intra-boundary time subunit and the motor speed of the power plant corresponding to the grid frequency value; The motor speed of the power plant in each time sub-unit within the boundary is processed by the difference between the motor rated speed and the motor to obtain the internal speed deviation state value of the time sub-unit within the boundary; Divide the out-of-bounds area into a number of out-of-bounds time sub-units according to the length of time; Obtain the grid frequency value at the middle moment of each out-of-bounds time subunit and the motor speed of the power plant corresponding to the grid frequency value; The motor speed of the power plant in each out-of-bounds time subunit is processed with the motor rated speed to obtain the out-of-bounds speed deviation state value of the out-of-bounds time subunit.

8. The method for intelligent frequency regulation control of a power plant and an energy storage system according to claim 7 is characterized in that: The difference between the inner speed deviation state value of the inner time subunit and the outer speed deviation state value of the outer time subunit is calculated to obtain the inner and outer speed deviation values; If the speed fluctuation value inside and outside the boundary is within the preset speed fluctuation value range inside and outside the boundary, it means that the abnormality of the power grid frequency has nothing to do with the motor speed of the power plant, and a speed interference-free signal is obtained; If the speed variation value inside and outside the boundary is outside the preset speed variation value range inside and outside the boundary, it means that the abnormal frequency of the power grid is related to the motor speed of the power plant, and a speed interference signal is obtained.

9. The method for intelligent frequency regulation control of a power plant and an energy storage system according to claim 8, characterized in that: Establish a plane coordinate system, with the number of time sub-units within the boundary as the X-axis and the motor speed or power generation of the power plant as the Y-axis; The motor speed corresponding to the time sub-unit within the boundary is plotted in order from large to small, and all the points corresponding to the motor speed are connected from left to right with a smooth curve to obtain a motor speed curve, and then the power plant electricity corresponding to the motor speed of each time sub-unit within the boundary is plotted in the coordinate system to obtain a power plant electricity curve; Identify the power curve of the power plant and obtain the correlation signal between the motor speed and power generation; Correlation signals include positive correlation signals and negative correlation signals.

10. The method for intelligent frequency regulation control of a power plant and an energy storage system according to claim 9, characterized in that: If the power curve of the power plant is not correlated with the changing trend of the motor speed curve, the power interval value in the out-of-bounds area and the power interval value in the non-out-of-bounds area are processed to complete the correlation processing between the power generation and the energy storage system.

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