Self-adaptive model prediction control method and system for primary frequency modulation of energy storage power station

Abstract

The invention discloses a self-adaptive model prediction control method and system for primary frequency modulation of an energy storage power station, relates to the technical field of power control, and solves the problem that efficient primary frequency modulation cannot be performed on an energy storage converter. Constructing a working process of the self-adaptive model, and outputting through the self-adaptive model to obtain an abnormal grid-connected point in the power grid; calculating an active power adjustment amount or a reactive power adjustment amount according to output data of the adaptive model; predicting power balance states of different grid-connected points in the power grid to obtain risk grid-connected points; when an abnormal grid-connected point or a risk grid-connected point exists in the power grid, the abnormal grid-connected point or the risk grid-connected point is correspondingly controlled, and efficient primary frequency modulation of the energy storage converter is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of power control, and in particular relates to an adaptive model predictive control method and system for primary frequency modulation of an energy storage power station. Background Art

[0002] Energy storage power stations are devices that can balance the mismatch between load and power supply in power systems. In power systems, power demand and supply are unstable. Especially during peak periods, power demand increases sharply, which will lead to excessive pressure on the power grid and even cause local power outages. Energy storage power stations can release stored energy when needed to meet the needs of the power grid and recharge during off-peak periods. As an important component of modern power systems, the frequency regulation function of energy storage power stations is crucial to maintaining the stability of the power grid. Among them, primary frequency regulation is one of the key links in the frequency regulation function of energy storage power stations. In existing technologies, most predictive control methods for primary frequency regulation in energy storage power stations only support electrical quantity collection at a few grid-connected points, making it difficult to reflect the real-time frequency and voltage status of the power grid from different grid-connected points. Furthermore, when adjusting the energy storage converters in energy storage power stations, most existing technologies only adjust individual converters and are unable to achieve coordinated power distribution across the converters through droop control. To this end, the present invention proposes an adaptive model predictive control method and system for primary frequency regulation of an energy storage power station. Summary of the Invention

[0003] The purpose of the present invention is to propose an adaptive model predictive control method and system for primary frequency regulation of an energy storage power station, so as to solve the problem of being unable to perform efficient primary frequency regulation on the energy storage converter raised in the above background technology.

[0004] The purpose of the present invention can be achieved through the following technical solutions: First, an adaptive model predictive control method for primary frequency regulation of an energy storage power station, the method comprising: Step S1, calibrating the measurement accuracy of the primary frequency modulation device; Step S2, constructing a workflow of the adaptive model, and obtaining abnormal grid connection points in the power grid through the adaptive model output; Step S3, calculating the active power adjustment amount or the reactive power adjustment amount according to the output data of the adaptive model; Step S4, predicting the power balance status of different grid connection points in the power grid, and predicting risky grid connection points; Step S5: When there are abnormal grid connection points or risky grid connection points in the power grid, corresponding control is performed on the abnormal grid connection points or risky grid connection points.

[0005] Furthermore, the calibration process in step S1 includes the following sub-steps: Step S11, connecting the primary frequency modulation device to the three-phase test circuit, inputting an initial current into the three-phase test circuit, and recording the input initial current as the input current value of different phases; Step S12, reading the actual current values ​​of different phases displayed on the primary frequency modulation device, subtracting the input current value from the actual current value and dividing the result by the input current value of the corresponding phase to obtain the current error rate of different phases in the primary frequency modulation device; Step S13, comparing the current error rates of different phases with the current error rate intervals; If the current error rates of all phases are within the current error rate range, the input current value is increased stepwise and steps S12 and S13 are repeated until the input current value reaches the current measurement range of the primary frequency modulation device; If the current error rate of any phase does not fall within the current error rate range, the primary frequency modulation device is calibrated until the current error rate of the corresponding phase falls within the current error rate range; In step S14, similarly, input the initial voltage into the three-phase test circuit respectively, and repeat step S12 to calculate the voltage error rate of different phases in the primary frequency modulation device, and compare the voltage error rate of different phases with the voltage error rate interval; If the voltage error rates of all phases are within the voltage error rate range, the input voltage value is increased stepwise and steps S12 and S13 are repeated until the input voltage value reaches the voltage measurement range of the primary frequency modulation device; If the voltage error rate of any phase does not fall within the voltage error rate range, the primary frequency modulation device is calibrated until the voltage error rate of the corresponding phase falls within the voltage error rate range.

[0006] Furthermore, the construction process in step S2 includes the following sub-steps: Step S21: first, real-time frequencies and real-time three-phase voltages of different grid connection points in the power grid at different time nodes are collected and used as input values ​​of the adaptive model; Step S22: After the input value enters the adaptive model, the real-time frequencies of different grid-connected points in the power grid at the current time node are compared with the standard frequency interval, and the real-time three-phase voltages of different grid-connected points in the power grid at the current time node are compared with the standard voltage interval; If the real-time frequency of any grid connection point in the power grid at the current time node is not within the standard frequency range, but the real-time three-phase voltages of all grid connection points are within the standard voltage range, the corresponding grid connection point is recorded as a frequency abnormal grid connection point and the process proceeds to step S23; If the real-time frequencies of all grid-connected points in the current time node are within the standard frequency range, but the real-time three-phase voltage of any grid-connected point is not within the standard voltage range, the corresponding grid-connected point is recorded as a voltage abnormal grid-connected point and the process proceeds to step S23; If the real-time frequencies of all grid-connected points in the current time node do not fall within the standard frequency range and the real-time three-phase voltages of all grid-connected points do not fall within the standard voltage range, a maintenance warning will be issued immediately; If the real-time frequencies of all grid-connected points in the current time node are within the standard frequency range and the real-time three-phase voltages of all grid-connected points are within the standard voltage range, then proceed to step S4; Step S23, recording the frequency abnormal grid connection point and the voltage abnormal grid connection point as abnormal grid connection points in the power grid, and recording the abnormal grid connection points as output data of the adaptive model; Step S24, record steps S21 to S23 as the workflow of the adaptive model.

[0007] Furthermore, the calculation process in step S3 includes the following sub-steps: Step S31, inputting the output data of the adaptive model into a primary frequency modulation device; Step S32: For the frequency abnormality grid connection point, the primary frequency regulation device calculates the active power adjustment amount of the energy storage power station through the AGC unit; In step S33, for the grid-connected point with abnormal voltage, the primary frequency regulation device calculates the reactive power adjustment amount of the energy storage power station through the AVC unit.

[0008] Furthermore, the calculation process in step S32 includes the following sub-steps: Step S321, obtaining the rated frequency, real-time frequency, rated active power of different energy storage converters, and the maximum frequency deviation allowed by the frequency abnormality grid connection point in the grid; Step S322, subtracting the rated frequency from the real-time frequency to obtain a frequency difference of the frequency abnormality connection point in the power grid; Step S323: Dividing the maximum frequency deviation by the rated active power of different energy storage power stations to obtain droop coefficients of different energy storage converters, and summing the reciprocals of the droop coefficients of different energy storage converters to obtain the reciprocal of the total droop coefficient of the energy storage power station; Step S324: Calculate and obtain the active power adjustment amount of the energy storage power station.

[0009] Furthermore, the calculation process in step S33 includes the following sub-steps: Step S331, obtaining the rated voltage, real-time voltage, rated reactive power of different energy storage converters, and the maximum voltage deviation allowed by the grid-connected point with abnormal voltage in the grid; Step S332: subtract the rated voltage from the real-time voltage to obtain the voltage difference of the grid connection point with abnormal voltage; Step S333: Dividing the maximum voltage deviation by the rated reactive power of different energy storage power stations to obtain droop coefficients of different energy storage converters, and summing the reciprocals of the droop coefficients of different energy storage converters to obtain the reciprocal of the total droop coefficient of the energy storage power station; Step S334: Calculate and obtain the reactive power adjustment amount of the energy storage power station.

[0010] Furthermore, the prediction process in step S4 includes the following sub-steps: Step S41, collecting the load three-phase voltage, load three-phase current and real-time phase difference of the load end at different grid connection points in the power grid at different time nodes, and recording the load three-phase voltage, load three-phase current and real-time phase difference as load electrical data; Step S42, calculating and obtaining the load line voltage at the load end of the grid connection point in the power grid, and recording the load three-phase current as the load line current at the load end of the grid connection point in the power grid; Step S43, calculating and obtaining the load active power at the load end of the grid connection point at different time nodes; Similarly, repeat steps S41 and S42 to collect load electrical data at the load end of the grid-connected point where the voltage is abnormal, and calculate the load reactive power at the load end of the grid-connected point at different time nodes. Step S44, repeating steps S41 to S43, to calculate the active power and reactive power of the power generation terminal at the grid connection point in the power grid at different time nodes; Step S45, subtracting the load active power from the generated active power of the grid connection point in the current time node from the load active power, and taking the absolute value to obtain the active power difference value of the grid connection point in the current time node; Similarly, the reactive power difference value of the grid-connected point in the current time node is obtained by subtracting the reactive power of the load from the generated reactive power of the grid-connected point in the current time node; Similarly, the active power difference and reactive power difference of the grid connection point at different time nodes are calculated; Step S46, analyzing the active power difference value and reactive power difference value of the grid connection point at different time nodes; Step S47: Record the frequency risk grid connection point and the voltage risk grid connection point as risky grid connection points.

[0011] Furthermore, the analysis process in step S46 includes the following sub-steps: Step S461, obtaining the maximum active power difference value and the maximum reactive power difference value allowed by the grid connection point in the power grid; Step S462: half of the maximum active power difference value is used as the active power difference warning value, and half of the maximum reactive power difference value is used as the reactive power difference warning value; Step S463: Record the time node corresponding to the active power difference value being greater than or equal to the active power difference warning value as the first time node, and record the time node corresponding to the active power difference value being less than the active power difference warning value as the second time node; Similarly, the time node corresponding to the reactive power difference value being greater than or equal to the reactive power difference warning value is recorded as the third time node, and the time node corresponding to the reactive power difference value being less than the reactive power difference warning value is recorded as the fourth time node; Step S464: Count the number of first time nodes and the number of second time nodes within the fixed time period, and compare the number of first time nodes and the number of second time nodes within the fixed time period; If the number of first time nodes is greater than or equal to the number of second time nodes within a fixed time period, the corresponding grid connection point will be recorded as a frequency risk grid connection point; If the number of first time nodes is less than the number of second time nodes within the fixed time period, no operation is performed; Similarly, the number of the third time nodes and the number of the fourth time nodes within the fixed time period are counted, and the number of the third time nodes and the number of the fourth time nodes within the fixed time period are compared; If the number of the third time nodes is greater than or equal to the number of the fourth time nodes within the fixed time period, the corresponding grid connection point will be recorded as a voltage risk grid connection point; If the number of the third time nodes within the fixed time period is less than the number of the fourth time nodes, no operation is performed.

[0012] Furthermore, the control process in step S5 includes the following sub-steps: Step S51, when the grid connection point in the power grid is a frequency abnormal grid connection point, the primary frequency regulation device controls the frequency abnormal grid connection point; The control process in step S51 includes the following sub-steps: Step S511, obtaining the rated active power of different energy storage converters, and summing the rated active power of the different energy storage converters to obtain the total rated active power of the energy storage power station; Step S512: dividing the rated active power of different energy storage converters by the total rated active power to obtain the proportion of the rated active power of the different energy storage converters; Step S513: multiplying the rated active power ratio by the active power adjustment amount to obtain individual active power adjustment amounts of different energy storage converters; Step S514, comparing the generated active power of the frequency abnormality grid connection point with the load active power; If the active power of the power generation at the grid-connected point with abnormal frequency in the power grid is greater than the active power of the load, different energy storage converters will be charged, and the charging power is the individual active power adjustment amount corresponding to different energy storage converters; If the active power of the power generation at the grid-connected point with abnormal frequency in the power grid is less than the active power of the load, the different energy storage converters will be discharged, and the discharge power is the individual active power adjustment amount corresponding to the different energy storage converters; Step S52: When the grid connection point in the power grid is a grid connection point with abnormal voltage, the primary frequency regulation device controls the grid connection point with abnormal voltage; The control process in step S52 includes the following sub-steps: Step S521, obtaining the rated reactive power of different energy storage converters, and summing the rated reactive power of the different energy storage converters to obtain the total rated reactive power of the energy storage power station; Step S522, dividing the rated reactive power of different energy storage converters by the total rated reactive power to obtain the rated reactive power ratio of different energy storage converters; Step S523, multiplying the rated reactive power ratio by the reactive power adjustment amount to obtain individual reactive power adjustments of different energy storage converters; Step S524, comparing the generated reactive power of the voltage abnormality grid connection point with the load reactive power; If the reactive power generated at the grid-connected point with abnormal voltage in the power grid is greater than the reactive power of the load, the energy storage converter is controlled to absorb reactive power. The amount absorbed by different energy storage converters is the corresponding individual reactive power adjustment amount. If the active power generated at the grid-connected point with abnormal frequency in the power grid is less than the active power of the load, the energy storage converter is controlled to generate reactive power. The output of different energy storage converters is the corresponding individual reactive power adjustment amount. Step S53: When the grid connection point in the power grid is a risky grid connection point, the primary frequency regulation device continuously monitors the risky grid connection point.

[0013] Secondly, the adaptive model predictive control system for primary frequency regulation of energy storage power stations includes: Data acquisition module, used to collect electrical data from different grid connection points in the power grid and send it to the data calibration module; Data calibration module, used to calibrate the measurement accuracy of the primary frequency modulation device; The data analysis module is used to build the workflow of the adaptive model and analyze the status of the grid connection points in the power grid. The analysis obtains normal status signals, frequency abnormal grid connection points, or voltage abnormal grid connection points. If a normal status signal is generated, it is sent to the power prediction module; if a frequency abnormal grid connection point or voltage abnormal grid connection point is obtained, it is sent to the data calculation module; A data calculation module is used to calculate the active power adjustment amount or reactive power adjustment amount of the energy storage power station and send it to the intelligent control module; The power prediction module is used to predict the power of the grid connection point after receiving the normal state signal, generate a power abnormality signal and send it to the intelligent control module; The intelligent control module is used to control the energy storage converter in the energy storage power station.

[0014] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. The present invention first calibrates the measurement accuracy of the primary frequency modulation device, then constructs an adaptive model workflow, and obtains frequency abnormality connection points or voltage abnormality connection points in the power grid through the adaptive model output. The present invention achieves accurate measurement of the primary frequency modulation device and preliminarily analyzes different abnormal connection points in the power grid; 2. The present invention also calculates the active power adjustment amount or reactive power adjustment amount based on the output data of the adaptive model. At the same time, it predicts the power balance state of normal grid connection points in the power grid and predicts risky grid connection points. The present invention realizes the calculation of the power adjustment amount of abnormal grid connection points and the prediction of the power balance state of normal grid connection points. 3. The present invention finally distributes the power adjustment amount to different energy storage converters in the energy storage power station, thereby performing corresponding control on different abnormal grid connection points in the power grid. This aspect realizes efficient primary frequency modulation of the energy storage converter. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] To facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0016] Figure 1 is a flow chart of the method of the present invention; Figure 2 It is the overall logic block diagram of the present invention; Figure 3 This is a block diagram of the overall system of the present invention. DETAILED DESCRIPTION

[0017] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0018] Example 1: Please refer to Figure 1 and Figure 2 As shown, the technical solution provided by the present invention is: an adaptive model predictive control method for primary frequency regulation of an energy storage power station. The method is suitable for analyzing the grid connection point in the power grid through a primary frequency regulation device, thereby controlling the energy storage power station and the energy storage converter in the energy storage power station. The method includes: Step S1, calibrating the measurement accuracy of the primary frequency modulation device; In this embodiment, the calibration process includes the following sub-steps: Step S11, connecting the primary frequency modulation device to the three-phase test circuit, inputting an initial current into the three-phase test circuit, and recording the input initial current as the input current value of different phases; Step S12, reading the actual current values ​​of different phases displayed on the primary frequency modulation device, subtracting the input current value from the actual current value and dividing the result by the input current value of the corresponding phase to obtain the current error rate of different phases in the primary frequency modulation device; Step S13, comparing the current error rates of different phases with the current error rate intervals; If the current error rates of all phases are within the current error rate range, the input current value is increased stepwise and steps S12 and S13 are repeated until the input current value reaches the current measurement range of the primary frequency modulation device; If the current error rate of any phase does not fall within the current error rate range, the primary frequency modulation device is calibrated until the current error rate of the corresponding phase falls within the current error rate range; In a specific implementation, the initial current may be 1A, the step-by-step increase in the input current value may be 1A each time, and the measurement range is the maximum value of the current that can be measured by the primary frequency modulation device. In this embodiment, the current measurement range may be 5A, and the current error rate range may be [-0.2%, 0.2%]; In step S14, similarly, input the initial voltage into the three-phase test circuit respectively, and repeat step S12 to calculate the voltage error rate of different phases in the primary frequency modulation device, and compare the voltage error rate of different phases with the voltage error rate interval; If the voltage error rates of all phases are within the voltage error rate range, the input voltage value is increased stepwise and steps S12 and S13 are repeated until the input voltage value reaches the voltage measurement range of the primary frequency modulation device; If the voltage error rate of any phase does not fall within the voltage error rate range, the primary frequency modulation device is calibrated until the voltage error rate of the corresponding phase falls within the voltage error rate range; In this embodiment, the voltage error rate interval can be [-0.2%, 0.2%], and the voltage measurement range can be 57.735V; in the specific implementation process, it is also necessary to compare the frequency error value of the primary frequency modulation device with the frequency error value interval. In this embodiment, the frequency error value interval can be [-0.003, 0.003]. The comparison process is similar to the current and voltage comparison process and will not be repeated here.

[0019] Step S2, constructing a workflow of the adaptive model, and obtaining abnormal grid connection points in the power grid through the adaptive model output; In this embodiment, the construction process in step S2 includes the following sub-steps: Step S21: first, real-time frequencies and real-time three-phase voltages of different grid connection points in the power grid at different time nodes are collected and used as input values ​​of the adaptive model; Step S22: After the input value enters the adaptive model, the real-time frequencies of different grid-connected points in the power grid at the current time node are compared with the standard frequency interval, and the real-time three-phase voltages of different grid-connected points in the power grid at the current time node are compared with the standard voltage interval; If the real-time frequency of any grid connection point in the power grid at the current time node is not within the standard frequency range, but the real-time three-phase voltages of all grid connection points are within the standard voltage range, the corresponding grid connection point is recorded as a frequency abnormal grid connection point and the process proceeds to step S23; If the real-time frequencies of all grid-connected points in the current time node are within the standard frequency range, but the real-time three-phase voltage of any grid-connected point is not within the standard voltage range, the corresponding grid-connected point is recorded as a voltage abnormal grid-connected point and the process proceeds to step S23; If the real-time frequencies of all grid-connected points in the current time node do not fall within the standard frequency range and the real-time three-phase voltages of all grid-connected points do not fall within the standard voltage range, a maintenance warning will be issued immediately; If the real-time frequencies of all grid-connected points in the current time node are within the standard frequency range and the real-time three-phase voltages of all grid-connected points are within the standard voltage range, then proceed to step S4; Step S23, recording the frequency abnormal grid connection point and the voltage abnormal grid connection point as abnormal grid connection points in the power grid, and recording the abnormal grid connection points as output data of the adaptive model; Step S24, recording steps S21 to S23 as the workflow of the adaptive model; It should be explained that the adaptive model can be realized by a primary frequency modulation device.

[0020] Step S3, calculating the active power adjustment amount or the reactive power adjustment amount according to the output data of the adaptive model; In this embodiment, the calculation process in step S3 includes the following sub-steps: Step S31, inputting the output data of the adaptive model into a primary frequency modulation device; In this embodiment, the output data can be connected to the primary frequency modulation device via GOOSE communication; Step S32: For the frequency abnormality grid connection point, the primary frequency regulation device calculates the active power adjustment amount of the energy storage power station through the AGC unit; Specifically, the calculation process in step S32 includes the following sub-steps: Step S321, obtaining the rated frequency f0, real-time frequency f1, rated active power of different energy storage converters, and the maximum frequency deviation allowed by the frequency abnormality point in the power grid; Step S322, subtracting the rated frequency from the real-time frequency to obtain a frequency difference Δf of the frequency abnormality connection point in the power grid; Step S323: Divide the maximum frequency deviation by the rated active power of different energy storage power stations to obtain the droop coefficients of different energy storage converters, and add the reciprocals of the droop coefficients of different energy storage converters to obtain the reciprocal K1 of the total droop coefficient of the energy storage power station; In the specific implementation process, the rated frequency f0 of the power grid is 50 Hz, and the rated active power of the energy storage converter can be obtained from the power generation technical specifications of the energy storage power station; Step S324 , calculating the active power adjustment ΔP of the energy storage power station using the formula ΔP=|Δf×(-K1)|; Step S33: For the grid connection point with abnormal voltage, the primary frequency regulation device calculates the reactive power adjustment amount of the energy storage power station through the AVC unit; In this embodiment, the calculation process in step S33 includes the following sub-steps: Step S331, obtaining the rated voltage U0, real-time voltage U1, rated reactive power of different energy storage converters and the maximum voltage deviation allowed by the grid-connected point with abnormal voltage in the grid; Step S332: subtract the rated voltage from the real-time voltage to obtain a voltage difference ΔU at the grid connection point where the voltage is abnormal. Step S333: Divide the maximum voltage deviation by the rated reactive power of different energy storage power stations to obtain droop coefficients of different energy storage converters, and add the reciprocals of the droop coefficients of different energy storage converters to obtain the reciprocal K2 of the total droop coefficient of the energy storage power station; In the specific implementation process, the rated voltage and maximum allowable voltage deviation of the power grid can be found based on the grid level of the power grid, and the rated reactive power of the energy storage converter can be obtained from the power generation technical specifications of the energy storage power station; Step S334 , calculating the reactive power adjustment ΔQ of the energy storage power station using the formula ΔQ=|ΔU×(-K2)|; It should be explained that the AGC unit and the AVC unit are calculation units inside the primary frequency modulation device.

[0021] Step S4, predicting the power balance status of different grid connection points in the power grid, and predicting risky grid connection points; In this embodiment, the prediction process in step S4 includes the following sub-steps: Step S41, collecting the load three-phase voltage U, load three-phase current and real-time phase difference XW at the load end of different grid connection points in the power grid at different time nodes, and recording the load three-phase voltage, load three-phase current and real-time phase difference as load electrical data; In this embodiment, taking a three-phase balanced circuit as an example, the three-phase balanced circuits are star-connected, the load three-phase voltage is the phase voltage, the load three-phase current is the phase current, and the real-time phase difference is the phase difference between the load three-phase voltage and the load three-phase current; Step S42, by formula The load line voltage UX at the load end of the grid connection point is calculated, and the three-phase current of the load is recorded as the load line current IX at the load end of the grid connection point; Step S43, by formula Calculate the load active power YG at the load end of the grid connection point at different time nodes; Similarly, repeat steps S41-S42 to collect the load electrical data of the load end of the abnormal voltage connection point in the power grid, and use the formula Calculate the reactive power WG of the load at the grid connection point at different time nodes; Step S44, repeating steps S41 to S43, to calculate the active power and reactive power of the power generation terminal at the grid connection point in the power grid at different time nodes; Step S45, subtracting the load active power from the generated active power of the grid connection point in the current time node from the load active power, and taking the absolute value to obtain the active power difference value of the grid connection point in the current time node; Similarly, the reactive power difference value of the grid-connected point in the current time node is obtained by subtracting the reactive power of the load from the generated reactive power of the grid-connected point in the current time node; Similarly, the active power difference and reactive power difference of the grid connection point at different time nodes are calculated; Step S46, analyzing the active power difference value and reactive power difference value of the grid connection point at different time nodes; In this embodiment, the analysis process in step S46 includes the following sub-steps: Step S461, obtaining the maximum active power difference value and the maximum reactive power difference value allowed by the grid connection point in the power grid; In a specific implementation process, the maximum active power difference value and the maximum reactive power difference value are preset values; Step S462: half of the maximum active power difference value is used as the active power difference warning value, and half of the maximum reactive power difference value is used as the reactive power difference warning value; Step S463: Record the time node corresponding to the active power difference value being greater than or equal to the active power difference warning value as the first time node, and record the time node corresponding to the active power difference value being less than the active power difference warning value as the second time node; Similarly, the time node corresponding to the reactive power difference value being greater than or equal to the reactive power difference warning value is recorded as the third time node, and the time node corresponding to the reactive power difference value being less than the reactive power difference warning value is recorded as the fourth time node; It should be explained that the first, second, third and fourth time nodes have no size relationship. The first, second, third and fourth are just names of the time nodes. Step S464: Count the number of first time nodes and the number of second time nodes within the fixed time period, and compare the number of first time nodes and the number of second time nodes within the fixed time period; If the number of first time nodes is greater than or equal to the number of second time nodes within a fixed time period, it indicates that there is an active power imbalance risk at the corresponding grid connection point, and the corresponding grid connection point is recorded as a frequency risk grid connection point; If the number of first time nodes is less than the number of second time nodes within the fixed time period, no operation is performed; Similarly, the number of the third time nodes and the number of the fourth time nodes within the fixed time period are counted, and the number of the third time nodes and the number of the fourth time nodes within the fixed time period are compared; If the number of the third time nodes within the fixed time period is greater than or equal to the number of the fourth time nodes, it indicates that there is a reactive power imbalance risk at the corresponding grid connection point, and the corresponding grid connection point is recorded as a voltage risk grid connection point; If the number of the third time nodes within the fixed time period is less than the number of the fourth time nodes, no operation is performed; Step S47: Record the frequency risk grid connection point and the voltage risk grid connection point as risky grid connection points.

[0022] Step S5: When there are abnormal grid connection points or risky grid connection points in the power grid, corresponding control is performed on the abnormal grid connection points or risky grid connection points; In this embodiment, the control process in step S5 includes the following sub-steps: Step S51, when the grid connection point in the power grid is a frequency abnormal grid connection point, the primary frequency regulation device controls the frequency abnormal grid connection point; In this embodiment, the control process in step S51 includes the following sub-steps: Step S511, obtaining the rated active power of different energy storage converters, and summing the rated active power of the different energy storage converters to obtain the total rated active power of the energy storage power station; Step S512: dividing the rated active power of different energy storage converters by the total rated active power to obtain the proportion of the rated active power of the different energy storage converters; Step S513: multiplying the rated active power ratio by the active power adjustment amount to obtain individual active power adjustment amounts of different energy storage converters; Step S514, comparing the generated active power of the frequency abnormality grid connection point with the load active power; If the active power of the power generation at the grid-connected point with abnormal frequency in the power grid is greater than the active power of the load, different energy storage converters will be charged, and the charging power is the individual active power adjustment amount corresponding to different energy storage converters; If the active power of the power generation at the grid-connected point with abnormal frequency in the power grid is less than the active power of the load, the different energy storage converters will be discharged, and the discharge power is the individual active power adjustment amount corresponding to the different energy storage converters; Step S52: When the grid connection point in the power grid is a grid connection point with abnormal voltage, the primary frequency regulation device controls the grid connection point with abnormal voltage; In this embodiment, the control process in step S52 includes the following sub-steps: Step S521, obtaining the rated reactive power of different energy storage converters, and summing the rated reactive power of the different energy storage converters to obtain the total rated reactive power of the energy storage power station; Step S522, dividing the rated reactive power of different energy storage converters by the total rated reactive power to obtain the rated reactive power ratio of different energy storage converters; Step S523, multiplying the rated reactive power ratio by the reactive power adjustment amount to obtain individual reactive power adjustments of different energy storage converters; Step S524, comparing the generated reactive power of the voltage abnormality grid connection point with the load reactive power; If the reactive power generated at the grid-connected point with abnormal voltage in the power grid is greater than the reactive power of the load, the energy storage converter is controlled to absorb reactive power. The amount absorbed by different energy storage converters is the corresponding individual reactive power adjustment amount. If the active power generated at the grid-connected point with abnormal frequency in the power grid is less than the active power of the load, the energy storage converter is controlled to generate reactive power. The output of different energy storage converters is the corresponding individual reactive power adjustment amount. Step S53: When the grid connection point in the power grid is a risky grid connection point, the primary frequency regulation device continuously monitors the risky grid connection point; It needs to be explained that the active power generated at the grid-connected point with abnormal frequency will not be equal to the active power of the load, and the reactive power generated at the grid-connected point with abnormal voltage will not be equal to the reactive power of the load.

[0023] Example 2: Please refer to Figure 3As shown, based on another concept of the same invention, an adaptive model predictive control system for primary frequency regulation of an energy storage power station is proposed, including a data acquisition module, a data calibration module, a data analysis module, a data calculation module, a power prediction module and an intelligent control module; The data acquisition module is used to collect electrical data from different grid connection points in the power grid and send it to the data calibration module; the data calibration module is used to calibrate the measurement accuracy of the primary frequency modulation device; the data analysis module is used to construct the workflow of the adaptive model and analyze the status of the grid connection points in the power grid, and the analysis obtains normal status signals, frequency abnormal grid connection points or voltage abnormal grid connection points. If a normal status signal is generated, it is sent to the power prediction module; if a frequency abnormal grid connection point or voltage abnormal grid connection point is obtained, it is sent to the data calculation module; the data calculation module is used to calculate the active power adjustment amount or reactive power adjustment amount of the energy storage power station and send it to the intelligent control module; the power prediction module is used to predict the power of the grid connection point in the power grid after receiving the normal status signal, predict and generate a power abnormality signal and send it to the intelligent control module; the intelligent control module is used to control the energy storage converter in the energy storage power station.

[0024] The preferred embodiments of the present invention disclosed above are intended only to help illustrate the present invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the present invention to specific embodiments. Obviously, many modifications and variations are possible based on the contents of this specification. These embodiments are selected and described in detail in this specification to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. An adaptive model predictive control method for primary frequency regulation of an energy storage power station, characterized in that: Methods include: Step S1, calibrating the measurement accuracy of the primary frequency modulation device; Step S2, constructing a workflow of the adaptive model, and obtaining abnormal grid connection points in the power grid through the adaptive model output; Step S3, calculating the active power adjustment amount or the reactive power adjustment amount according to the output data of the adaptive model; Step S4, predicting the power balance status of different grid connection points in the power grid, and predicting risky grid connection points; Step S5: When there are abnormal grid connection points or risky grid connection points in the power grid, corresponding control is performed on the abnormal grid connection points or risky grid connection points.

2. The adaptive model predictive control method for primary frequency modulation of an energy storage power station according to claim 1, characterized in that: The calibration process in step S1 includes the following sub-steps: Step S11, connecting the primary frequency modulation device to the three-phase test circuit, inputting an initial current into the three-phase test circuit, and recording the input initial current as the input current value of different phases; Step S12, reading the actual current values ​​of different phases displayed on the primary frequency modulation device, subtracting the input current value from the actual current value and dividing the result by the input current value of the corresponding phase to obtain the current error rate of different phases in the primary frequency modulation device; Step S13, comparing the current error rates of different phases with the current error rate intervals; If the current error rates of all phases are within the current error rate range, the input current value is increased stepwise and steps S12 and S13 are repeated until the input current value reaches the current measurement range of the primary frequency modulation device; If the current error rate of any phase does not fall within the current error rate range, the primary frequency modulation device is calibrated until the current error rate of the corresponding phase falls within the current error rate range; In step S14, similarly, input the initial voltage into the three-phase test circuit respectively, and repeat step S12 to calculate the voltage error rate of different phases in the primary frequency modulation device, and compare the voltage error rate of different phases with the voltage error rate interval; If the voltage error rates of all phases are within the voltage error rate range, the input voltage value is increased stepwise and steps S12 and S13 are repeated until the input voltage value reaches the voltage measurement range of the primary frequency modulation device; If the voltage error rate of any phase does not fall within the voltage error rate range, the primary frequency modulation device is calibrated until the voltage error rate of the corresponding phase falls within the voltage error rate range.

3. The adaptive model predictive control method for primary frequency modulation of an energy storage power station according to claim 2, characterized in that: The construction process in step S2 includes the following sub-steps: Step S21: first, real-time frequencies and real-time three-phase voltages of different grid connection points in the power grid at different time nodes are collected and used as input values ​​of the adaptive model; Step S22: After the input value enters the adaptive model, the real-time frequencies of different grid-connected points in the power grid at the current time node are compared with the standard frequency interval, and the real-time three-phase voltages of different grid-connected points in the power grid at the current time node are compared with the standard voltage interval; If the real-time frequency of any grid connection point in the power grid at the current time node is not within the standard frequency range, but the real-time three-phase voltages of all grid connection points are within the standard voltage range, the corresponding grid connection point is recorded as a frequency abnormal grid connection point and the process proceeds to step S23; If the real-time frequencies of all grid-connected points in the current time node are within the standard frequency range, but the real-time three-phase voltage of any grid-connected point is not within the standard voltage range, the corresponding grid-connected point is recorded as a voltage abnormal grid-connected point and the process proceeds to step S23; If the real-time frequencies of all grid-connected points in the current time node do not fall within the standard frequency range and the real-time three-phase voltages of all grid-connected points do not fall within the standard voltage range, a maintenance warning will be issued immediately; If the real-time frequencies of all grid-connected points in the current time node are within the standard frequency range and the real-time three-phase voltages of all grid-connected points are within the standard voltage range, then proceed to step S4; Step S23, recording the frequency abnormal grid connection point and the voltage abnormal grid connection point as abnormal grid connection points in the power grid, and recording the abnormal grid connection points as output data of the adaptive model; Step S24, record steps S21 to S23 as the workflow of the adaptive model.

4. The adaptive model predictive control method for primary frequency modulation of an energy storage power station according to claim 3, characterized in that: The calculation process in step S3 includes the following sub-steps: Step S31, inputting the output data of the adaptive model into a primary frequency modulation device; Step S32: For the frequency abnormality grid connection point, the primary frequency regulation device calculates the active power adjustment amount of the energy storage power station through the AGC unit; In step S33, for the grid-connected point with abnormal voltage, the primary frequency regulation device calculates the reactive power adjustment amount of the energy storage power station through the AVC unit.

5. The adaptive model predictive control method for primary frequency modulation of an energy storage power station according to claim 4, characterized in that: The calculation process in step S32 includes the following sub-steps: Step S321, obtaining the rated frequency, real-time frequency, rated active power of different energy storage converters, and the maximum frequency deviation allowed by the frequency abnormality grid connection point in the grid; Step S322, subtracting the rated frequency from the real-time frequency to obtain a frequency difference of the frequency abnormality connection point in the power grid; Step S323: Dividing the maximum frequency deviation by the rated active power of different energy storage power stations to obtain droop coefficients of different energy storage converters, and summing the reciprocals of the droop coefficients of different energy storage converters to obtain the reciprocal of the total droop coefficient of the energy storage power station; Step S324: Calculate and obtain the active power adjustment amount of the energy storage power station.

6. The adaptive model predictive control method for primary frequency regulation of an energy storage power station according to claim 5, characterized in that: The calculation process in step S33 includes the following sub-steps: Step S331, obtaining the rated voltage, real-time voltage, rated reactive power of different energy storage converters, and the maximum voltage deviation allowed by the grid-connected point with abnormal voltage in the grid; Step S332: subtract the rated voltage from the real-time voltage to obtain the voltage difference of the grid connection point with abnormal voltage; Step S333: Dividing the maximum voltage deviation by the rated reactive power of different energy storage power stations to obtain droop coefficients of different energy storage converters, and summing the reciprocals of the droop coefficients of different energy storage converters to obtain the reciprocal of the total droop coefficient of the energy storage power station; Step S334: Calculate and obtain the reactive power adjustment amount of the energy storage power station.

7. The adaptive model predictive control method for primary frequency modulation of an energy storage power station according to claim 6, characterized in that: The prediction process in step S4 includes the following sub-steps: Step S41, collecting the load three-phase voltage, load three-phase current and real-time phase difference of the load end at different grid connection points in the power grid at different time nodes, and recording the load three-phase voltage, load three-phase current and real-time phase difference as load electrical data; Step S42, calculating and obtaining the load line voltage at the load end of the grid connection point in the power grid, and recording the load three-phase current as the load line current at the load end of the grid connection point in the power grid; Step S43, calculating and obtaining the load active power at the load end of the grid connection point at different time nodes; Similarly, repeat steps S41 and S42 to collect load electrical data at the load end of the grid-connected point where the voltage is abnormal, and calculate the load reactive power at the load end of the grid-connected point at different time nodes. Step S44, repeating steps S41 to S43, to calculate the active power and reactive power of the power generation terminal at the grid connection point in the power grid at different time nodes; Step S45, subtracting the load active power from the generated active power of the grid connection point in the current time node from the load active power, and taking the absolute value to obtain the active power difference value of the grid connection point in the current time node; Similarly, the reactive power difference value of the grid-connected point in the current time node is obtained by subtracting the reactive power of the load from the generated reactive power of the grid-connected point in the current time node; Similarly, the active power difference and reactive power difference of the grid connection point at different time nodes are calculated; Step S46, analyzing the active power difference value and reactive power difference value of the grid connection point at different time nodes; Step S47: Record the frequency risk grid connection point and the voltage risk grid connection point as risky grid connection points.

8. The adaptive model predictive control method for primary frequency regulation of an energy storage power station according to claim 7, characterized in that: The analysis process in step S46 includes the following sub-steps: Step S461, obtaining the maximum active power difference value and the maximum reactive power difference value allowed by the grid connection point in the power grid; Step S462: half of the maximum active power difference value is used as the active power difference warning value, and half of the maximum reactive power difference value is used as the reactive power difference warning value; Step S463: Record the time node corresponding to the active power difference value being greater than or equal to the active power difference warning value as the first time node, and record the time node corresponding to the active power difference value being less than the active power difference warning value as the second time node; Similarly, the time node corresponding to the reactive power difference value being greater than or equal to the reactive power difference warning value is recorded as the third time node, and the time node corresponding to the reactive power difference value being less than the reactive power difference warning value is recorded as the fourth time node; Step S464: Count the number of first time nodes and the number of second time nodes within the fixed time period, and compare the number of first time nodes and the number of second time nodes within the fixed time period; If the number of first time nodes is greater than or equal to the number of second time nodes within a fixed time period, the corresponding grid connection point will be recorded as a frequency risk grid connection point; If the number of first time nodes is less than the number of second time nodes within the fixed time period, no operation is performed; Similarly, the number of the third time nodes and the number of the fourth time nodes within the fixed time period are counted, and the number of the third time nodes and the number of the fourth time nodes within the fixed time period are compared; If the number of the third time nodes within the fixed time period is greater than or equal to the number of the fourth time nodes, the corresponding grid connection point will be recorded as a voltage risk grid connection point; If the number of the third time nodes within the fixed time period is less than the number of the fourth time nodes, no operation is performed.

9. The adaptive model predictive control method for primary frequency regulation of an energy storage power station according to claim 8, characterized in that: The control process in step S5 includes the following sub-steps: Step S51: When the grid connection point in the power grid is a frequency abnormal grid connection point, the primary frequency regulation device controls the frequency abnormal grid connection point. The control process is as follows: Step S511, obtaining the rated active power of different energy storage converters, and summing the rated active power of the different energy storage converters to obtain the total rated active power of the energy storage power station; Step S512: dividing the rated active power of different energy storage converters by the total rated active power to obtain the proportion of the rated active power of the different energy storage converters; Step S513: multiplying the rated active power ratio by the active power adjustment amount to obtain individual active power adjustment amounts of different energy storage converters; Step S514, comparing the generated active power of the frequency abnormality grid connection point with the load active power; If the active power of the power generation at the grid-connected point with abnormal frequency in the power grid is greater than the active power of the load, different energy storage converters will be charged, and the charging power is the individual active power adjustment amount corresponding to different energy storage converters; If the active power of the power generation at the grid-connected point with abnormal frequency in the power grid is less than the active power of the load, the different energy storage converters will be discharged, and the discharge power is the individual active power adjustment amount corresponding to the different energy storage converters; In step S52, when the grid connection point in the power grid is a grid connection point with abnormal voltage, the primary frequency regulation device controls the grid connection point with abnormal voltage. The control process is specifically as follows: Step S521, obtaining the rated reactive power of different energy storage converters, and summing the rated reactive power of the different energy storage converters to obtain the total rated reactive power of the energy storage power station; Step S522, dividing the rated reactive power of different energy storage converters by the total rated reactive power to obtain the rated reactive power ratio of different energy storage converters; Step S523, multiplying the rated reactive power ratio by the reactive power adjustment amount to obtain individual reactive power adjustments of different energy storage converters; Step S524, comparing the generated reactive power of the voltage abnormality grid connection point with the load reactive power; If the reactive power generated at the grid-connected point with abnormal voltage in the power grid is greater than the reactive power of the load, the energy storage converter is controlled to absorb reactive power. The amount absorbed by different energy storage converters is the corresponding individual reactive power adjustment amount. If the active power generated at the grid-connected point with abnormal frequency in the power grid is less than the active power of the load, the energy storage converter is controlled to generate reactive power. The output of different energy storage converters is the corresponding individual reactive power adjustment amount. Step S53: When the grid connection point in the power grid is a risky grid connection point, the primary frequency regulation device continuously monitors the risky grid connection point.

10. The adaptive model predictive control system for primary frequency regulation of energy storage power station is characterized by: In combination with the adaptive model predictive control method for primary frequency regulation of an energy storage power station according to any one of claims 1 to 9, the method comprises: Data acquisition module, used to collect electrical data from different grid connection points in the power grid and send it to the data calibration module; Data calibration module, used to calibrate the measurement accuracy of the primary frequency modulation device; The data analysis module is used to build the workflow of the adaptive model and analyze the status of the grid connection points in the power grid. The analysis obtains normal status signals, frequency abnormal grid connection points, or voltage abnormal grid connection points. If a normal status signal is generated, it is sent to the power prediction module; if a frequency abnormal grid connection point or voltage abnormal grid connection point is obtained, it is sent to the data calculation module; A data calculation module is used to calculate the active power adjustment amount or reactive power adjustment amount of the energy storage power station and send it to the intelligent control module; The power prediction module is used to predict the power of the grid connection point after receiving the normal state signal, generate a power abnormality signal and send it to the intelligent control module; The intelligent control module is used to control the energy storage converter in the energy storage power station.

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