Adaptive control method for power grid system

Abstract

The invention discloses a self-adaptive control method for a power grid system, and relates to the technical field of power distribution, and the method comprises the steps: carrying out the self-adaptive control based on the monitoring of the operation state data of each region of a power grid, can adjust the alternating current frequency of each region in real time, and facilitates the guarantee that the power grid deals with the electric energy quality problem caused by frequency fluctuation in a short time. And secondly, by analyzing the dynamic characteristic data of the power grid, the dynamic stability index value of each region is obtained, PID control parameters are dynamically adjusted, the adaptive capacity of the power grid to dynamic disturbance can be enhanced through adaptive control, and the stability and reliability of the system are improved. Meanwhile, by combining the frequency stability index value, the dynamic stability index value and the power grid line load data, the load fluctuation value of each region is further obtained, and the power distribution among the regions is optimized according to the fluctuation values, so that the power transmission loss and the fault risk caused by imbalance or emergencies can be effectively reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of power distribution, and in particular to an adaptive control method for a power grid system. Background Art

[0002] With the continuous expansion of modern power grids and the increase in the proportion of renewable energy access, the complexity and uncertainty of power grid operation have increased significantly. Adaptive control technology can maintain safe and stable operation of the power grid in an uncertain environment by monitoring the operating status of the power grid in real time, including key parameters such as frequency, power, and voltage, and dynamically adjusting system parameters with advanced algorithms and controllers.

[0003] Prior art, such as the invention patent with publication number: CN116780510A, discloses an adaptive control system for power grid interconnection and large power grid safety and stability, including: a power grid data acquisition module: used to collect interconnected power grid data; a power grid data processing module: used to process the collected power grid data; an adaptive control module: used to adaptively control the interconnected power grid based on an adaptive adjustment algorithm; an adaptive adjustment module: used to adaptively adjust abnormal control conditions in the interconnected power grid.

[0004] Prior art, such as the microgrid frequency adaptive learning control method disclosed in the invention patent with announcement number: CN108448594B. It aims to solve the problem that the prior art cannot effectively adjust the frequency of the microgrid and improve the stability of the microgrid frequency. A microgrid frequency adaptive learning control method is provided, including calculating the second state parameter of the microgrid system based on the first state parameter of the microgrid system acquired in advance; calculating the control matrix and the disturbance matrix of the microgrid system according to the second state parameter and the first neural network model constructed in advance; calculating the utility function of the microgrid system according to the second state parameter; calculating the cost function of the microgrid system according to the utility function; and using an adaptive dynamic programming method to calculate the optimal control law of the microgrid system frequency based on the second state parameter, the control matrix, the disturbance matrix, the utility function and the cost function.

[0005] At present, in the adaptive control process of the power grid system, there are grid load fluctuations and power generation imbalance, which leads to deviations in system frequency, affecting the real-time operation status of the power grid and may cause grid instability. Summary of the invention

[0006] In view of the deficiencies of the prior art, the present invention provides an adaptive control method for a power grid system, which can effectively solve the problems involved in the above-mentioned background technology.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions: an adaptive control method for a power grid system, comprising acquiring and analyzing power grid operation status data of each area of ​​the power grid, obtaining frequency stability index values ​​of each area of ​​the power grid, and adjusting the AC power frequency of each area of ​​the power grid according to the frequency stability index values ​​of each area of ​​the power grid.

[0008] The dynamic characteristic data of the power grid in each area of ​​the power grid are obtained and analyzed to obtain the dynamic stability index value of the power grid in each area of ​​the power grid. According to the dynamic stability index value of the power grid in each area of ​​the power grid, the PID parameters of each area of ​​the power grid are dynamically adjusted through the controller.

[0009] According to the frequency stability index value of each area of ​​the power grid and the power grid dynamic stability index value of each area of ​​the power grid, and combined with the line data of each area of ​​the power grid, the load fluctuation value of each area of ​​the power grid is obtained, and the power of each area of ​​the power grid is allocated according to the load fluctuation value of each area of ​​the power grid.

[0010] Furthermore, the acquisition and analysis of the grid operation status data of each area of ​​the grid includes: extracting the grid operation status data of each area of ​​the grid, including the total power consumption of the grid, reactive power, and power exchange between each area of ​​the grid.

[0011] The total power consumption of the power grid, reactive power, and power exchange between different areas of the power grid are extracted in each preset monitoring cycle, and the voltage amplitude of the main substation in each area of ​​the power grid in each monitoring cycle is counted.

[0012] The actual frequency of AC power in each area of ​​the power grid in each monitoring period is obtained, and the nominal frequency of AC power stored in the database is extracted. The absolute value of the difference between the actual frequency of AC power in each area of ​​the power grid in each monitoring period and the nominal frequency of AC power is processed to obtain the actual deviation frequency of AC power in each area of ​​the power grid in each monitoring period.

[0013] Furthermore, the frequency stability index value of each area of ​​the power grid is obtained by extracting the total power consumption, total reactive power, voltage amplitude of the main substation and actual deviation frequency of AC power in each area of ​​the power grid in each monitoring period, and obtaining the frequency stability index value of each area of ​​the power grid after processing. The frequency stability index value of each area of ​​the power grid is used to indicate the degree of frequency fluctuation deviation.

[0014] Furthermore, the AC power frequency of each area of ​​the power grid is adjusted according to the frequency stability index value of each area of ​​the power grid. The specific process is: according to the frequency stability index value of each area of ​​the power grid, and compared with the frequency stability index threshold of each area of ​​the power grid stored in the database, if the frequency stability index value of each area of ​​the power grid is higher than or equal to the frequency stability index threshold of each area of ​​the power grid, then there is no need to adjust the AC power frequency of each area of ​​the power grid; if the frequency stability index value of each area of ​​the power grid is lower than the frequency stability index threshold of each area of ​​the power grid, then the AC power frequency is adjusted by increasing the speed of the generator through the speed regulator control.

[0015] Furthermore, the dynamic characteristic data of the power grid in each area of ​​the power grid is obtained and analyzed to obtain the dynamic stability index value of the power grid in each area of ​​the power grid. The specific process is: extracting the dynamic characteristic data of the power grid in each area of ​​the power grid in each monitoring time period, including the bus voltage, equivalent damping coefficient and power grid frequency in each power grid area, and obtaining the duration of the monitoring time period, and obtaining the dynamic stability index value of the power grid in each area of ​​the power grid after processing.

[0016] Furthermore, the PID parameters of each area of ​​the power grid are dynamically adjusted through the controller according to the power grid dynamic stability index value of each area of ​​the power grid. The specific process is: according to the power grid dynamic stability index value of each area of ​​the power grid, and compared with the power grid dynamic stability index threshold of each area of ​​the power grid stored in the database, if the power grid dynamic stability index value of each area of ​​the power grid is higher than or equal to the power grid dynamic stability index threshold of each area of ​​the power grid, then there is no need to adjust the PID parameters of each area of ​​the power grid; if the power grid dynamic stability index value of each area of ​​the power grid is lower than the power grid dynamic stability index threshold of each area of ​​the power grid, then the proportional coefficient and the differential coefficient are increased by the controller.

[0017] Furthermore, the line data of each area of ​​the power grid includes power consumption of each area of ​​the power grid, the maximum capacity of the power grid, the main line load rate and the spare capacity of the power grid.

[0018] The power consumption of each area of ​​the power grid and the maximum capacity of the power grid are extracted and the difference is processed to obtain the remaining available capacity of each area of ​​the power grid.

[0019] Furthermore, the load fluctuation value of each area of ​​the power grid is obtained, and the specific process is: extracting the remaining available capacity of each area of ​​the power grid, the main line load rate and the remaining spare capacity of the power grid, and extracting the frequency stability index value of each area of ​​the power grid and the power grid dynamic stability index value of each area of ​​the power grid to obtain the load fluctuation value of each area of ​​the power grid. The load fluctuation value of each area of ​​the power grid is represented to reflect the amplitude of the load change in each area of ​​the power grid.

[0020] Furthermore, the power of each area of ​​the power grid is allocated according to the load fluctuation value of each area of ​​the power grid. The specific process is: extract the load fluctuation value of each area of ​​the power grid, compare the load fluctuation value of each area of ​​the power grid with the added power value corresponding to each interval of the load fluctuation value of each area of ​​the power grid stored in the database, obtain the added power value of each area of ​​the power grid, and allocate the power of each area of ​​the power grid according to the added power value of each area of ​​the power grid.

[0021] Furthermore, the specific analysis conditions of the power grid dynamic stability index values ​​of each area of ​​the power grid are as follows: ; In the formula, represents the dynamic stability index value of the power grid in the ith area of ​​the power grid, represents the instantaneous voltage change rate of the bus voltage in the ith area of ​​the power grid during the monitoring period, T represents the duration of the monitoring period, represents the grid frequency of the ith area of ​​the grid in the jth monitoring cycle, represents the equivalent damping coefficient of the ith region of the power grid in the jth monitoring cycle, represents the equivalent damping coefficient of the ith region of the power grid in the j-1th monitoring period, Indicates the set limit damping coefficient difference, Indicates the set bus voltage reference change rate, Indicates the set reference grid frequency, Indicates the correction factor corresponding to the set equivalent damping coefficient, Indicates the correction factor corresponding to the set voltage change rate, It indicates the correction factor corresponding to the set grid frequency, i indicates the number of each grid area, , n represents the total number of power grid areas, j represents the number of each monitoring period, , m represents the total number of monitoring cycles.

[0022] The present invention has the following beneficial effects: (1) The present invention provides an adaptive control method for a power grid system. First, based on the monitoring of the operating status data of each area of ​​the power grid, the adaptive control can adjust the AC frequency of each area in real time, which helps to ensure that the power grid can cope with power quality problems caused by frequency fluctuations in a short time. Secondly, by analyzing the dynamic characteristic data of the power grid, the dynamic stability index value of each area is obtained, and the PID control parameters are dynamically adjusted. The adaptive control can enhance the adaptability of the power grid to dynamic disturbances and improve the stability and reliability of the system. At the same time, combined with the frequency stability index value, the dynamic stability index value and the power grid line load data, the load fluctuation value of each area is further obtained, and the power distribution between areas is optimized according to these fluctuation values, which can effectively reduce the power transmission loss and failure risk caused by imbalance or emergencies.

[0023] (2) The present invention obtains the frequency stability index value of each area of ​​the power grid through comprehensive monitoring and analysis of the power grid system operation data to reflect the comprehensive situation of frequency fluctuations, adjusts the AC power frequency by controlling the increase or decrease of the generator speed through the speed regulator, uses the frequency stability index as the adjustment basis, and monitors the frequency and power parameters in real time to enhance the accuracy and efficiency of the control decision-making, and dynamically adjusts the generator operation status, so as to maintain the stability of the power quality under the condition of unbalanced load or external disturbance.

[0024] (3) The present invention obtains the dynamic stability index value of the power grid in each area of ​​the power grid. In a complex power grid environment with multiple variables and dynamic disturbances, the system can quickly determine the stability problem and take targeted measures to adjust the control strategy by analyzing the dynamic characteristic data in real time. By adjusting the PID parameters, the dynamic performance of the power grid is optimized, so that the system can respond to load fluctuations or external disturbances more efficiently and avoid potential instability.

[0025] (4) The present invention helps determine and adjust the electric power value of each area by obtaining the load fluctuation value of each area of ​​the power grid, and dynamically adjusts the power distribution of each area of ​​the power grid accordingly. Based on real-time monitoring and data analysis, the precise power distribution strategy is determined by comparison, thereby optimizing the utilization of power grid resources and helping to ensure that the power grid operation can quickly adapt to changes in load demand.

[0026] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the method flow of the present invention. DETAILED DESCRIPTION

[0028] 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.

[0029] In the description of the present invention, it should be understood that the terms "opening", "upper", "lower", "thickness", "top", "middle", "length", "inside", "all around" and the like indicating orientation or positional relationship are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the components or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0030] See also Figure 1 As shown, an embodiment of the present invention provides a technical solution for an adaptive control method for a power grid system: an adaptive control method for a power grid system, comprising acquiring and analyzing power grid operation status data of each area of ​​the power grid, obtaining a frequency stability index value of each area of ​​the power grid, and adjusting the AC power frequency of each area of ​​the power grid according to the frequency stability index value of each area of ​​the power grid.

[0031] The dynamic characteristic data of the power grid in each area of ​​the power grid are obtained and analyzed to obtain the dynamic stability index value of the power grid in each area of ​​the power grid. According to the dynamic stability index value of the power grid in each area of ​​the power grid, the PID parameters of each area of ​​the power grid are dynamically adjusted through the controller.

[0032] According to the frequency stability index value of each area of ​​the power grid and the power grid dynamic stability index value of each area of ​​the power grid, and combined with the line data of each area of ​​the power grid, the load fluctuation value of each area of ​​the power grid is obtained, and the power of each area of ​​the power grid is allocated according to the load fluctuation value of each area of ​​the power grid.

[0033] It should be noted that the frequency and load changes of the power grid are monitored, and the control parameters (such as the gain of the PID controller) are automatically adjusted to cope with load fluctuations and unbalanced power generation, thereby ensuring the stability of the system frequency. Frequency deviation correction ensures that the operating frequency of the power grid remains within the specified range. Power regulation between multi-regional power grids in adaptive control ensures the power balance of power generation and load in the region. A multi-regional power grid frequency and power adaptive control system is formed, which can coordinately control the frequency stability in a single region.

[0034] Specifically, the grid operation status data of each area of ​​the grid is obtained and analyzed. The specific process is: extracting the grid operation status data of each area of ​​the grid, including the total power consumption of the grid, reactive power, and power exchange between each area of ​​the grid.

[0035] The total power consumption of the power grid, reactive power, and power exchange between different areas of the power grid are extracted in each preset monitoring cycle, and the voltage amplitude of the main substation in each area of ​​the power grid in each monitoring cycle is counted.

[0036] The actual frequency of AC power in each area of ​​the power grid in each monitoring period is obtained, and the nominal frequency of AC power stored in the database is extracted. The absolute value of the difference between the actual frequency of AC power in each area of ​​the power grid in each monitoring period and the nominal frequency of AC power is processed to obtain the actual deviation frequency of AC power in each area of ​​the power grid in each monitoring period.

[0037] Specifically, the frequency stability index value of each area of ​​the power grid is obtained. The specific process is: extract the total power consumption of the power grid, the total reactive power, the voltage amplitude of the main substation in each area of ​​the power grid in each monitoring period, and the actual deviation frequency of the alternating current in each area of ​​the power grid in each monitoring period, and obtain the frequency stability index value of each area of ​​the power grid after processing. The frequency stability index value of each area of ​​the power grid is used to indicate the degree of frequency fluctuation deviation.

[0038] It should be noted that the frequency stability index values ​​of each area of ​​the power grid are analyzed under the following specific conditions: ; In the formula, represents the frequency stability index value of the ith area of ​​the power grid, represents the total power consumption of the grid in the i-th area of ​​the grid during the j-th monitoring period, represents the total reactive power of the ith area of ​​the power grid in the jth monitoring cycle, represents the voltage amplitude of the main substation in the i-th area of ​​the power grid in the j-th monitoring cycle, represents the actual deviation frequency of the AC power in the i-th area of ​​the power grid in the j-th monitoring cycle, Indicates the total power consumption of the reference grid. Indicates the set reference total reactive power, Indicates the voltage amplitude set with reference to the main substation. Indicates the actual deviation frequency of the reference AC power. Indicates the correction factor corresponding to the set total power consumption of the power grid, Indicates the correction factor corresponding to the set total reactive power, Indicates the correction factor corresponding to the set voltage amplitude, It indicates the correction factor corresponding to the actual deviation frequency of the set AC power, i indicates the number of each area of ​​the power grid, , n represents the total number of power grid areas, j represents the number of each monitoring period, , m represents the total number of monitoring cycles.

[0039] In a specific embodiment, the parameters such as the total power consumption of the power grid in each area of ​​the power grid, the total reactive power, the voltage amplitude of the main substation, and the actual deviation frequency of the alternating current in each monitoring cycle do not exist in isolation, but are interdependent and closely related. First, the total power consumption of the power grid directly affects the change in the voltage amplitude of the main substation. When the power consumption of the power grid increases, the voltage of the main substation may decrease due to the increase in load, thereby affecting the frequency stability of the power grid. Secondly, there is an important coupling relationship between the total reactive power and the voltage amplitude. Higher reactive power demand will aggravate voltage fluctuations, thereby increasing the fluctuation amplitude of the actual deviation frequency of the alternating current, which has an adverse effect on frequency stability. In addition, the change in the actual deviation frequency of the alternating current reflects the dynamic characteristics of the power grid operation state. Excessive frequency fluctuations may require adjustment of the voltage amplitude and reactive power to relieve pressure. By comprehensively considering the relationship between these parameters, the frequency stability index values ​​of various areas of the power grid can be more accurately evaluated, thereby providing a basis for subsequent operation optimization and control.

[0040] In a specific embodiment, the correction factor corresponding to the total power consumption of the power grid generally ranges from 0 to 1. When in use, the correction factor corresponding to the total power consumption of the power grid can be directly obtained from the database. The correspondence between the total power consumption of the power grid and its corresponding correction factor is determined by a pre-set mapping table. For example, by analyzing the frequency fluctuation amplitude under different load levels, a mapping table between the total power consumption of the power grid and the correction factor is constructed. The total power consumption value of the power grid detected in real time can be input into the mapping table to quickly obtain the corresponding correction factor, thereby helping to optimize the power allocation and frequency adjustment strategy.

[0041] In a specific embodiment, the correction factor corresponding to the total reactive power also ranges from 0 to 1. The corresponding relationship is established by analyzing the impact of reactive power changes on voltage fluctuations. For example, by constructing a mapping table between total reactive power and correction factors. In actual operation, the reactive power value detected in real time is input into the mapping table, so as to quickly obtain the correction factor for auxiliary voltage control and reactive compensation strategy adjustment.

[0042] In a specific embodiment, the correction factor corresponding to the voltage amplitude is usually used to evaluate the impact of voltage deviation on the frequency stability of the power grid, and its value range is also between 0 and 1. By analyzing the relationship between historical voltage deviation data and frequency deviation, a mapping table between voltage amplitude and correction factor is constructed. The voltage amplitude deviation detected in real time can be directly used to find the correction factor, thereby guiding the optimization of reactive power regulation and voltage stability measures.

[0043] In a specific embodiment, the correction factor corresponding to the actual deviation frequency of the alternating current is used to quantify the impact of the frequency deviation on the dynamic stability of the power grid, and its value range is also between 0 and 1. By generating a mapping table between the frequency deviation and the correction factor. During operation, after the frequency deviation value detected in real time is input into the mapping table, the correction factor corresponding to the actual deviation frequency of the alternating current can be quickly determined.

[0044] In this implementation plan, attention is paid to the real-time operation status of the power grid, mainly the frequency deviation and power balance status. Real-time control of active power helps to eliminate frequency deviation and stabilize the frequency near the nominal value (such as 50 Hz or 60 Hz).

[0045] Specifically, the AC power frequency of each area of ​​the power grid is adjusted according to the frequency stability index value of each area of ​​the power grid. The specific process is: according to the frequency stability index value of each area of ​​the power grid, and compared with the frequency stability index threshold of each area of ​​the power grid stored in the database, if the frequency stability index value of each area of ​​the power grid is higher than or equal to the frequency stability index threshold of each area of ​​the power grid, there is no need to adjust the AC power frequency of each area of ​​the power grid; if the frequency stability index value of each area of ​​the power grid is lower than the frequency stability index threshold of each area of ​​the power grid, the AC power frequency is adjusted by increasing the speed of the generator through speed regulator control.

[0046] Specifically, the dynamic characteristic data of the power grid in each area of ​​the power grid are obtained and analyzed to obtain the dynamic stability index value of the power grid in each area of ​​the power grid. The specific process is: extract the dynamic characteristic data of the power grid in each area of ​​the power grid in each monitoring time period, including the bus voltage, equivalent damping coefficient and power grid frequency in each power grid area, and obtain the duration of the monitoring time period, and obtain the dynamic stability index value of the power grid in each area of ​​the power grid after processing.

[0047] Specifically, according to the power grid dynamic stability index value of each area of ​​the power grid, the PID parameters of each area of ​​the power grid are dynamically adjusted through the controller. The specific process is: according to the power grid dynamic stability index value of each area of ​​the power grid, and compared with the power grid dynamic stability index threshold of each area of ​​the power grid stored in the database, if the power grid dynamic stability index value of each area of ​​the power grid is higher than or equal to the power grid dynamic stability index threshold of each area of ​​the power grid, there is no need to adjust the PID parameters of each area of ​​the power grid; if the power grid dynamic stability index value of each area of ​​the power grid is lower than the power grid dynamic stability index threshold of each area of ​​the power grid, the proportional coefficient and the differential coefficient are increased by the controller.

[0048] It should be noted that the role of proportional gain is to make the controller more sensitive to the deviation of the grid frequency. When the proportional gain is large, the system responds faster; increasing the proportional gain will make the control system respond to the deviation faster, thereby accelerating the frequency regulation. Usually, you can increase the proportional gain by 10% to 30% based on the original value to test the system response. For example, if the original proportional gain is 1.0, you can try to adjust it to between 1.1 and 1.3.

[0049] It should be noted that the differential gain is used to adjust the system's response to the rate of change of frequency, helping to suppress oscillations and improve the damping of the system. Increasing the differential coefficient can increase the system's suppression ability and reduce overshoot or oscillation during the system's response. The adjustment range of the differential gain is usually small, and can start from an increase of 5% to 10%. For example, if the original differential coefficient is 0.5, it can be adjusted to between 0.55 and 0.6.

[0050] Specifically, the line data of each area of ​​the power grid includes the power consumption of each area of ​​the power grid, the maximum capacity of the power grid, the main line load rate and the spare capacity of the power grid.

[0051] The power consumption of each area of ​​the power grid and the maximum capacity of the power grid are extracted and the difference is processed to obtain the remaining available capacity of each area of ​​the power grid.

[0052] It should be noted that the remaining available capacity refers to the difference between the current maximum load (power consumption) of the power grid and the maximum capacity of the power grid. This value indicates how much additional load the power grid can carry without exceeding the maximum capacity of the power grid.

[0053] Specifically, the load fluctuation value of each area of ​​the power grid is obtained. The specific process is: extract the remaining available capacity of each area of ​​the power grid, the main line load rate and the remaining spare capacity of the power grid, and extract the frequency stability index value of each area of ​​the power grid and the power grid dynamic stability index value of each area of ​​the power grid to obtain the load fluctuation value of each area of ​​the power grid. The load fluctuation value of each area of ​​the power grid is used to reflect the amplitude of the load change in each area of ​​the power grid.

[0054] It should be noted that the load fluctuation values ​​of each area of ​​the power grid are analyzed under the following specific conditions: ; In the formula, represents the load fluctuation value of the jth area of ​​the power grid, represents the remaining available capacity of the ith area of ​​the power grid, represents the main line load rate of the ith area of ​​the power grid, represents the remaining reserve capacity of the power grid in the ith area of ​​the power grid, represents the frequency stability index value of the jth area of ​​the power grid, represents the dynamic stability index value of the power grid in the ith area of ​​the power grid, Indicates the weight factor corresponding to the set remaining available capacity. Indicates the weight factor corresponding to the set main line load rate, Indicates the weight factor corresponding to the set reserve capacity of the power grid, Indicates the weight factor corresponding to the set frequency stability index value, Indicates the weight factor corresponding to the set power grid dynamic stability index value.

[0055] It should be noted that the main line load rate of the i-th area of ​​the power grid indicates the proportion of the actual load of the main transmission line in the i-th area to its designed maximum load capacity. The actual load power of the main line is the total power currently borne by the main transmission lines in the area, and the unit is usually MW (megawatt). The design rated power of the main line is the maximum power that the line can safely transmit during design, and the unit is also usually MW.

[0056] It should be noted that the reserve capacity refers to the power generation capacity reserved in the area to deal with emergencies (such as load fluctuations, failures, etc.), and the remaining reserve capacity of the power grid refers to the reserve power generation capacity that has not been used after the power grid meets the current load demand, that is, the difference between the current power generation equipment operating at maximum rated power and the current actual output.

[0057] It should be noted that the weight factor corresponding to the remaining available capacity represents the numerical value of the influence of the remaining available capacity on the load fluctuation assessment value of the power grid. This corresponding relationship is determined by a preset mapping relationship. For example, the actual value of the remaining available capacity and the preset remaining available capacity value stored in the database form a mapping set. By inputting the remaining available capacity calculated in real time into the mapping set, its corresponding weight factor can be obtained for further analyzing the load fluctuation condition of the power grid.

[0058] It should be noted that the weight factor corresponding to the main line load rate represents the numerical value of the contribution of the main line load rate to the grid load fluctuation assessment value. The corresponding relationship is established through a predefined mapping table. For example, based on historical operation data, the specific value of the main line load rate is compared with the preset load rate value in the database, and a corresponding weight factor mapping table is formed. When the main line load rate is monitored in real time, the corresponding weight factor can be obtained by inputting it into the mapping table, which is used to analyze the rationality and volatility of grid load distribution.

[0059] It should be noted that the weight factor corresponding to the grid reserve capacity represents the degree of influence of the reserve capacity on the grid load fluctuation assessment value. This correspondence is determined by constructing a mapping table between the preset value of the reserve capacity and the weight factor. For example, the real-time value of the grid reserve capacity is associated with different preset reserve capacity interval values ​​in the database. By querying the mapping table, the weight factor corresponding to the reserve capacity is quickly obtained to evaluate the stability and regulation capability of the grid.

[0060] It should be noted that the weight factor corresponding to the frequency stability index value represents the weight of the impact of the index on the grid load fluctuation assessment value. This relationship is determined by a mapping table constructed by the preset interval of the frequency stability index value and the weight factor. For example, different frequency stability index value intervals and their corresponding weight factors are stored in the monitoring database. When the frequency stability index value monitored in real time is input into the mapping table, the corresponding weight factor can be quickly obtained for optimizing the frequency control strategy and stability analysis.

[0061] It should be noted that the weight factor corresponding to the power grid dynamic stability index value represents the degree of influence of the power grid dynamic stability on the load fluctuation assessment value. This is achieved by presetting the mapping relationship between the power grid dynamic stability index value interval and its corresponding weight factor. For example, an associated mapping set between the dynamic stability index value and the weight factor is established based on historical data, and the power grid dynamic stability index value calculated in real time is input into the mapping set, and its weight factor can be obtained to further evaluate the impact of dynamic stability on load scheduling.

[0062] Specifically, the power of each area of ​​the power grid is allocated according to the load fluctuation value of each area of ​​the power grid. The specific process is: extract the load fluctuation value of each area of ​​the power grid, compare the load fluctuation value of each area of ​​the power grid with the added power value corresponding to each interval of the load fluctuation value of each area of ​​the power grid stored in the database, obtain the added power value of each area of ​​the power grid, and allocate the power of each area of ​​the power grid according to the added power value of each area of ​​the power grid.

[0063] It should be noted that the power allocation of each area of ​​the power grid is carried out according to the added value of the power in each area of ​​the power grid. Specifically, each area first calls on its own remaining available capacity to try to meet the added value demand of the power. If the resources in the area are sufficient, the allocation is completed directly. If the area cannot fully meet the demand, the power generation resources are borrowed from the neighboring areas.

[0064] Specifically, the dynamic stability index values ​​of the power grid in each area of ​​the power grid are analyzed under the following conditions: ; In the formula, represents the dynamic stability index value of the power grid in the ith area of ​​the power grid, represents the instantaneous voltage change rate of the bus voltage in the ith area of ​​the power grid during the monitoring period, T represents the duration of the monitoring period, represents the grid frequency of the ith area of ​​the grid in the jth monitoring cycle, represents the equivalent damping coefficient of the ith region of the power grid in the jth monitoring cycle, represents the equivalent damping coefficient of the ith region of the power grid in the j-1th monitoring period, Indicates the set limit damping coefficient difference, Indicates the set bus voltage reference change rate, Indicates the set reference grid frequency, Indicates the correction factor corresponding to the set equivalent damping coefficient, Indicates the correction factor corresponding to the set voltage change rate, It indicates the correction factor corresponding to the set grid frequency, i indicates the number of each grid area, , n represents the total number of power grid areas, j represents the number of each monitoring period, , m represents the total number of monitoring cycles.

[0065] It should be noted that a larger difference in damping coefficients means a significant increase in damping coefficients, which indicates better grid stability.

[0066] It should be noted that the grid frequency can be directly obtained by digital protection devices (such as microcomputer protection), and the equivalent damping coefficient can impose small disturbances (such as load shedding, small adjustment of power generation) to measure the dynamic changes of frequency and power, obtain the active power change and frequency change, and divide the active power change by the frequency change to obtain the power-frequency sensitivity of the system.

[0067] It should be noted that the bus voltage change rate, equivalent damping coefficient and grid frequency in each power grid area do not exist independently, but are interdependent and closely related. First, the bus voltage change rate directly reflects the short-term dynamic response characteristics of the power grid. If the bus voltage change rate is large, it means that the system responds violently when facing load fluctuations or disturbances, which may lead to increased fluctuations in the grid frequency, thereby adversely affecting dynamic stability. Secondly, there is a close connection between the equivalent damping coefficient and the grid frequency. The change in the damping coefficient determines the system's ability to suppress oscillations, while the change in frequency is a direct manifestation of whether the oscillation is effectively suppressed. A lower damping coefficient may lead to an increase in the amplitude of frequency fluctuations, thereby affecting the overall stability of the system. In addition, the size of the bus voltage change rate may also affect the dynamic adjustment ability of the damping coefficient. When the voltage change rate is large, the system may need to rely on a higher damping coefficient to suppress fluctuations and maintain frequency stability. On the contrary, if the voltage change rate is small and the damping coefficient is high, the frequency fluctuation can be effectively reduced and the dynamic stability can be improved. Therefore, when calculating the dynamic stability index values ​​of each area of ​​the power grid, it is necessary to comprehensively consider the correlation between these three parameters and make coordinated adjustments so that the system can reach a stable state more quickly under dynamic disturbances.

[0068] In a specific embodiment, the correction factor corresponding to the equivalent damping coefficient generally ranges from 0 to 1. When in use, the correction factor corresponding to the equivalent damping coefficient can be directly obtained from the database. The correspondence between the correction factor corresponding to the equivalent damping coefficient and the equivalent damping coefficient is determined by a pre-set mapping table. For example, by analyzing historical data and the dynamic stability characteristics of the power grid, a mapping table between the equivalent damping coefficient and its correction factor is constructed. The equivalent damping coefficient detected in real time is input into the mapping table, and the corresponding correction factor can be quickly obtained, thereby optimizing the evaluation and adjustment of the damping characteristics during the analysis of the dynamic characteristics of the power grid.

[0069] In a specific embodiment, the value range of the correction factor corresponding to the voltage change rate is usually between 0 and 1. When in use, the correction factor corresponding to the voltage change rate can be directly extracted from the database. The corresponding relationship between the voltage change rate and the correction factor is established by analyzing the system response characteristics and voltage fluctuation tolerance. By inputting the voltage change rate collected in real time into the mapping table, the corresponding correction factor can be quickly found, thereby enhancing the dynamic response capability of the system.

[0070] In a specific embodiment, the correction factor corresponding to the grid frequency also has a value range between 0 and 1. The correction factor establishes a corresponding mapping table between frequency and correction factor by analyzing the relationship between frequency deviation and system stability. When the real-time monitored grid frequency deviation value is input into the mapping table, the corresponding correction factor can be quickly obtained, which can more effectively reflect the actual impact of frequency fluctuations on the dynamic stability of the system and help achieve accurate system control and regulation.

[0071] It should be noted that the adaptive control method for the power grid system also includes a database for storing the frequency stability index thresholds of each area of ​​the power grid, the power grid dynamic stability index thresholds of each area of ​​the power grid, the power generation increase corresponding to each interval of the load fluctuation value of each area of ​​the power grid, the defined damping coefficient difference, the bus voltage reference change rate, the reference power grid frequency, the correction factor corresponding to the equivalent damping coefficient, the correction factor corresponding to the voltage change rate, the correction factor corresponding to the power grid frequency, the weight factor corresponding to the remaining available capacity, the weight factor corresponding to the main line load rate, the weight factor corresponding to the standby capacity of the power grid, the weight factor corresponding to the frequency stability index value, the weight factor corresponding to the power grid dynamic stability index value, the reference power grid total power consumption, the reference total reactive power, the reference voltage amplitude of the main substation, the reference AC actual deviation frequency, the correction factor corresponding to the total power consumption of the power grid, the correction factor corresponding to the total reactive power, the correction factor corresponding to the voltage amplitude, and the correction factor corresponding to the actual deviation frequency of the AC power.

[0072] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0073] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. An adaptive control method for a power grid system, characterized in that: include: Obtain and analyze the power grid operation status data of each area of ​​the power grid to obtain the frequency stability index value of each area of ​​the power grid, and adjust the AC power frequency of each area of ​​the power grid according to the frequency stability index value of each area of ​​the power grid; Obtain and analyze the dynamic characteristic data of each area of ​​the power grid to obtain the dynamic stability index value of each area of ​​the power grid, and dynamically adjust the PID parameters of each area of ​​the power grid through the controller according to the dynamic stability index value of each area of ​​the power grid; According to the frequency stability index value of each area of ​​the power grid and the power grid dynamic stability index value of each area of ​​the power grid, and combined with the line data of each area of ​​the power grid, the load fluctuation value of each area of ​​the power grid is obtained, and the power of each area of ​​the power grid is allocated according to the load fluctuation value of each area of ​​the power grid.

2. The adaptive control method for a power grid system according to claim 1, characterized in that: The specific process of obtaining and analyzing the power grid operation status data of each area of ​​the power grid is as follows: Extract the grid operation status data of each area of ​​the grid, including the total power consumption of the grid, reactive power, and the power exchange between the grid areas; Extract the total power consumption of the power grid, reactive power, and power exchange between different areas of the power grid in each preset monitoring cycle, and count the voltage amplitude of the main substation in each area of ​​the power grid in each monitoring cycle; The actual frequency of AC power in each area of ​​the power grid in each monitoring period is obtained, and the nominal frequency of AC power stored in the database is extracted. The absolute value of the difference between the actual frequency of AC power in each area of ​​the power grid in each monitoring period and the nominal frequency of AC power is processed to obtain the actual deviation frequency of AC power in each area of ​​the power grid in each monitoring period.

3. The adaptive control method for a power grid system according to claim 2, characterized in that: The specific process of obtaining the frequency stability index value of each area of ​​the power grid is as follows: The total power consumption, total reactive power, voltage amplitude of main substation and actual deviation frequency of AC power in each area of ​​the power grid in each monitoring period are extracted, and the frequency stability index value of each area of ​​the power grid is obtained after processing. The frequency stability index value of each area of ​​the power grid is used to indicate the degree of frequency fluctuation deviation.

4. The adaptive control method for a power grid system according to claim 3, characterized in that: The specific process of adjusting the AC power frequency of each area of ​​the power grid according to the frequency stability index value of each area of ​​the power grid is as follows: According to the frequency stability index value of each area of ​​the power grid, it is compared with the frequency stability index threshold of each area of ​​the power grid stored in the database. If the frequency stability index value of each area of ​​the power grid is higher than or equal to the frequency stability index threshold of each area of ​​the power grid, there is no need to adjust the AC power frequency of each area of ​​the power grid. If the frequency stability index value of each area of ​​the power grid is lower than the frequency stability index threshold of each area of ​​the power grid, the speed of the generator is increased by the speed regulator to adjust the AC power frequency.

5. The adaptive control method for a power grid system according to claim 1, characterized in that: The specific process of acquiring and analyzing the dynamic characteristic data of each area of ​​the power grid to obtain the dynamic stability index value of each area of ​​the power grid is as follows: The dynamic characteristic data of the power grid in each area of ​​the power grid are extracted in each monitoring time period, including the bus voltage, equivalent damping coefficient and power grid frequency in each power grid area, and the duration of the monitoring time period is obtained. After processing, the dynamic stability index value of the power grid in each area of ​​the power grid is obtained.

6. The adaptive control method for a power grid system according to claim 1, characterized in that: According to the dynamic stability index value of each area of ​​the power grid, the PID parameters of each area of ​​the power grid are dynamically adjusted by the controller. The specific process is as follows: According to the power grid dynamic stability index value of each area of ​​the power grid, it is compared with the power grid dynamic stability index threshold of each area of ​​the power grid stored in the database. If the power grid dynamic stability index value of each area of ​​the power grid is higher than or equal to the power grid dynamic stability index threshold of each area of ​​the power grid, there is no need to adjust the PID parameters of each area of ​​the power grid. If the power grid dynamic stability index value of each area of ​​the power grid is lower than the power grid dynamic stability index threshold of each area of ​​the power grid, the proportional coefficient and the differential coefficient are increased by the controller.

7. The adaptive control method for a power grid system according to claim 1, characterized in that: The line data of each area of ​​the power grid includes the power consumption of each area of ​​the power grid, the maximum capacity of the power grid, the main line load rate and the spare capacity of the power grid; The power consumption of each area of ​​the power grid and the maximum capacity of the power grid are extracted and the difference is processed to obtain the remaining available capacity of each area of ​​the power grid.

8. The adaptive control method for a power grid system according to claim 7, characterized in that: The specific process of obtaining the load fluctuation value of each area of ​​the power grid is as follows: The remaining available capacity of each area of ​​the power grid, the main line load rate and the remaining spare capacity of the power grid are extracted, and the frequency stability index value of each area of ​​the power grid and the power grid dynamic stability index value of each area of ​​the power grid are extracted to obtain the load fluctuation value of each area of ​​the power grid. The load fluctuation value of each area of ​​the power grid is used to reflect the amplitude degree of load change in each area of ​​the power grid.

9. The adaptive control method for a power grid system according to claim 6, characterized in that: The power of each area of ​​the power grid is allocated according to the load fluctuation value of each area of ​​the power grid. The specific process is: Extract the load fluctuation value of each area of ​​the power grid, compare the load fluctuation value of each area of ​​the power grid with the power generation increase value corresponding to each interval of the load fluctuation value of each area of ​​the power grid stored in the database, obtain the power increase value of each area of ​​the power grid, and allocate the power of each area of ​​the power grid according to the power increase value of each area of ​​the power grid.

10. The adaptive control method for a power grid system according to claim 5, characterized in that: The specific analysis conditions of the dynamic stability index value of the power grid in each area of ​​the power grid are: ； In the formula, represents the dynamic stability index value of the power grid in the ith area of ​​the power grid, represents the instantaneous voltage change rate of the bus voltage in the ith area of ​​the power grid during the monitoring period, T represents the duration of the monitoring period, represents the grid frequency of the ith area of ​​the grid in the jth monitoring cycle, represents the equivalent damping coefficient of the ith region of the power grid in the jth monitoring cycle, represents the equivalent damping coefficient of the ith region of the power grid in the j-1th monitoring period, Indicates the set limit damping coefficient difference, Indicates the set bus voltage reference change rate, Indicates the set reference grid frequency. Indicates the correction factor corresponding to the set equivalent damping coefficient, Indicates the correction factor corresponding to the set voltage change rate, It indicates the correction factor corresponding to the set grid frequency, i indicates the number of each grid area, , n represents the total number of power grid areas, j represents the number of each monitoring period, , m represents the total number of monitoring cycles.

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