Method and system for evaluating grid-connected performance of new energy station

Abstract

The invention discloses a new energy station grid-connected performance evaluation method and system, and relates to the technical field of power system analysis and control. Comprising the following steps: preprocessing original data; electrical parameter fundamental component extraction and calculation are carried out on the processed data; and calculating the power set value control capability by using the extracted quantity, estimating a frequency parameter by using an adaptive notch filtering method, and judging whether the requirement is met or not. Through implementation of the steps of original data preprocessing, parameter extraction calculation, power control calculation, frequency evaluation and the like, the accuracy of grid-connected performance evaluation is ensured; abnormal data are corrected by adopting a variable joint matching method, a smooth filtering method and the like, missing data are supplemented in combination with interpolation processing, and the data quality and reliability in the evaluation process are ensured; frequency parameters are estimated and optimized by establishing an adaptive notch filtering method, a complete evaluation system is constructed based on electrical parameter calculation and power control calculation, and the operation efficiency of the station is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of power system analysis and control, and in particular to a method and system for evaluating the grid-connected performance of a new energy station. Background Art

[0002] The scale of new energy access represented by wind power and photovoltaic power will further increase and replace conventional power sources, and the power system backup optimization strategy will change. The power grid faces challenges in dealing with power fluctuations and shortages, voltage and reactive power balance characteristics, and grid dispatching and control in emergency situations. Unlike conventional power sources, the power generation of new energy presents random fluctuations. Its grid-connected operation changes the single random system with random load into a dual random system with random changes in both power supply and load. Therefore, it is urgent to grasp the grid-connected performance of new energy stations in real time, and combine the prediction results to improve the dispatchability and controllability of new energy power generation.

[0003] In addition, the current power dispatching department mostly adopts a centralized approach to the processing of new energy data information, that is, a database is established in the power grid dispatching center to store real-time measurement data and evaluation results, and all analysis, calculation and application are implemented in the dispatching center. Since the amount of data required for performance evaluation at the operation level is much larger than that at the planning level, this approach has many shortcomings, such as limited transmission channels, large maintenance, and high risks. Therefore, the engineering application threshold of centralized grid-connected performance evaluation of new energy stations is high and the actual effect is poor. Edge computing improves data processing efficiency and solves the computing resource pressure of the main station by migrating some computing tasks to computing resources near the data source for on-site operation and processing. This idea can be introduced into the grid-connected performance evaluation of new energy stations to ensure and enhance the grid's perception of the grid-connected performance of new energy stations and its dispatching and operation control capabilities. Summary of the invention

[0004] In view of the problems existing in the prior art, the present invention is proposed.

[0005] Therefore, the problem to be solved by the present invention is how to reduce the communication burden in the performance evaluation of grid-connected renewable energy stations based on the idea of ​​edge computing, and improve the grid's perception and operating efficiency of grid-connected renewable energy stations.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] In a first aspect, an embodiment of the present invention provides a method for evaluating the grid-connected performance of a new energy station, which includes preprocessing raw data;

[0008] Extract and calculate the fundamental wave components of electrical parameters from the processed data;

[0009] Utilize the extracted quantity to calculate the power setpoint control capability;

[0010] Adaptive notch filtering is used to estimate the frequency parameters and determine whether they meet the requirements.

[0011] As a preferred solution of the method for evaluating the grid-connected performance of new energy stations of the present invention, the preprocessing of the original data includes: correcting or deleting abnormal data caused by human factors by using a method for judging the threshold value;

[0012] Abnormal data caused by system reasons are corrected by using variable joint matching method and smoothing filtering method;

[0013] And interpolate the missing data in a specific period;

[0014] Preprocessing can improve the operation efficiency of stations and enhance the grid’s ability to perceive the connection of new energy stations to the grid.

[0015] As a preferred solution of the method for evaluating the grid-connected performance of new energy stations of the present invention, the extraction and calculation of the fundamental wave components of the electrical parameters include: extracting the fundamental positive sequence component of the voltage by sequence quantity decomposition method, including the positive sequence component of the voltage, the negative sequence component of the voltage and the zero sequence component of the voltage;

[0016] Calculate the positive sequence active current based on the positive sequence component, including the calculation of active power and the extraction of the fundamental positive sequence component of voltage and current;

[0017] Calculate positive sequence reactive current based on sequence quantity, including reactive power calculation;

[0018] The fundamental wave component extraction and calculation provide a basis for subsequent power setting value control.

[0019] As a preferred solution of the method for evaluating the grid-connected performance of a new energy station of the present invention, the power setting value control capability calculation includes: calculating the maximum deviation of active power according to the phase difference between the positive sequence component of voltage and the positive sequence active current;

[0020] Calculate the maximum deviation of reactive power based on the positive sequence component of the voltage fundamental wave;

[0021] Calculate response time based on setpoint control start and end times;

[0022] Evaluate the grid-connected performance of the station through calculation.

[0023] As a preferred solution of the method for evaluating the grid-connected performance of new energy stations of the present invention, the adaptive notch filtering method includes: using two coefficients for filtering control and configuring parameters for the two coefficients;

[0024] The frequency estimation value is obtained by iterative calculation;

[0025] and comparing it with a preset range to determine whether the frequency estimate meets the requirement;

[0026] If the requirements are met, the operation is terminated; if the requirements are not met, the power setting value control capability calculation is returned.

[0027] As a preferred solution of the new energy station grid connection performance evaluation method of the present invention, the coefficient iterative calculation process of the adaptive notch filter method includes:

[0028] Iterative calculation is performed through the filtering formula:

[0029]

[0030] Among them, d1 and d2 represent two filtering coefficients. represents the value of coefficient d1 after k calculations, γ represents the gain, and y k represents the notch output value after k calculations, p k represents the sensitivity related to d1, r2 represents the pole radius determined by the coefficient d2, f represents the frequency estimate, and T represents the sampling period;

[0031] The notch output value y k The calculation is performed by decomposing the positive sequence component of the voltage fundamental wave into:

[0032]

[0033] Where U1, U2 and U3 represent the positive sequence component, negative sequence component and zero sequence component of voltage respectively, a represents the operator, and U a , U b and U c Represent the voltages of phase A, phase B and phase C respectively;

[0034] Based on the calculation results, it is determined whether the frequency estimation value meets the requirements.

[0035] As a preferred solution of the new energy station grid connection performance evaluation method of the present invention, the frequency estimation value judgment process includes:

[0036] When the frequency estimate does not meet the preset range requirements, the power setting value control capability calculation is returned, including:

[0037] Calculation of maximum deviation of active power:

[0038]

[0039] Among them, σ p Indicates the maximum deviation of active power, Indicates the phase difference between the positive sequence voltage component and the positive sequence active current, Pm Indicates the active power setting target value;

[0040] Calculation of maximum reactive power deviation:

[0041]

[0042] Among them, σ Q Indicates the maximum deviation of reactive power, Q m Indicates reactive power setting target value;

[0043] Response time calculation:

[0044] t p =t p,1 -t p,2

[0045] Among them, t p Represents the response time, t p,1 Indicates the start time of set value control, t p,2 Indicates the end time of set value control;

[0046] The frequency estimation value is recalculated according to the calculation result until the frequency estimation value meets the preset maximum and minimum value range requirements.

[0047] In a second aspect, an embodiment of the present invention provides a new energy station grid-connected performance evaluation system, which includes a data preprocessing module, a parameter extraction module, a power control module and a frequency evaluation module;

[0048] The data preprocessing module is used to analyze, organize, modify and edit the original data, perform threshold correction or system cause correction on abnormal data, and perform interpolation processing on missing data;

[0049] The parameter extraction module is used to extract the voltage fundamental positive sequence component, calculate the positive sequence active current and the positive sequence reactive current from the processed data;

[0050] The power control module is used to calculate the maximum deviation of active power, the maximum deviation of reactive power and the response time based on the extracted electrical parameters;

[0051] The frequency evaluation module is used to estimate the frequency parameters by using an adaptive notch filter method, and to determine whether the frequency estimation value meets the requirements. If it does not meet the requirements, it returns to the power control module for recalculation.

[0052] In a third aspect, an embodiment of the present invention provides a computer device, including a memory and a processor, wherein the memory stores a computer program, wherein: when the computer program instructions are executed by the processor, the steps of the new energy station grid-connected performance evaluation method as described in the first aspect of the present invention are implemented.

[0053] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein: when the computer program instructions are executed by a processor, the steps of the new energy station grid-connected performance evaluation method as described in the first aspect of the present invention are implemented.

[0054] The beneficial effects of the present invention are as follows: the new energy station grid-connected performance evaluation method provided by the present invention ensures the accuracy and reliability of the grid-connected performance evaluation and improves the evaluation efficiency by implementing the steps of raw data preprocessing, parameter extraction calculation, power control calculation and frequency evaluation; by correcting abnormal data by adopting the variable joint matching method, smoothing filtering method and the like, and supplementing the missing data by combining interpolation processing, the accuracy of data processing is improved, the communication burden is reduced, and the data quality and reliability of the evaluation process are ensured; by establishing an adaptive notch filtering method to estimate and optimize the frequency parameters, a complete evaluation system is constructed based on electrical parameter calculation and power control calculation, the station operation efficiency is improved, and the grid-connected perception capability of the power grid to the new energy station is improved, and the scientificity and efficiency of the evaluation method are guaranteed. The present invention achieves better results in terms of data processing efficiency, communication burden and grid-connected perception capability. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0056] Figure 1 This is a flow chart of the grid-connected performance evaluation method for new energy stations;

[0057] Figure 2 This is a comparison chart of frequency parameter estimation results of the new energy station grid-connected performance evaluation method;

[0058] Figure 3 This is the squared error diagram of frequency parameter estimation for the new energy station grid connection performance evaluation method. DETAILED DESCRIPTION

[0059] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0060] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0061] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0062] Example 1

[0063] Reference Figure 1 This is the first embodiment of the present invention, which provides a method for evaluating the grid-connected performance of a new energy station, comprising:

[0064] S1, preprocessing the original data;

[0065] It should be noted that the original data is divided into real-time data and historical data. Real-time data includes operating parameters such as voltage, current, and power, which are used to monitor the real-time status of the station; historical data includes operating records, fault records, etc., which are used to evaluate the overall performance of the station. The system uses standard communication protocols to collect these data.

[0066] S2, extracting and calculating the fundamental wave components of electrical parameters from the processed data;

[0067] It should be noted that the fundamental component extraction adopts a method based on sequence decomposition, which mainly includes the decomposition of three-phase voltage and current signals. The three-phase signal is decomposed into positive sequence, negative sequence and zero sequence components, laying the foundation for subsequent power calculation. This decomposition method can effectively suppress the influence of harmonic interference.

[0068] S3, using the extracted amount to calculate the power setting value control capability;

[0069] It should be noted that the power setpoint control adopts a calculation method based on phase difference. This method determines the active power deviation by analyzing the voltage and current phase difference, and calculates the reactive power deviation by the voltage fundamental component. At the same time, the response time calculation is introduced to evaluate the control effect.

[0070] S4, using the adaptive notch filter method to estimate the frequency parameters and determine whether they meet the requirements.

[0071] It should be noted that the adaptive notch filter adopts a dual coefficient control structure and has strong adaptive capabilities. This method can automatically adjust the filter parameters according to the system operation status to improve the accuracy of frequency estimation. When the estimation result does not meet the requirements, the system will optimize and adjust through the feedback mechanism.

[0072] In summary, the new energy station grid-connected performance evaluation method provided by the present invention ensures the accuracy and reliability of the grid-connected performance evaluation and improves the evaluation efficiency by implementing the steps of raw data preprocessing, parameter extraction calculation, power control calculation and frequency evaluation; by adopting the variable joint matching method, smoothing filtering method, etc. to correct the abnormal data, and combining the interpolation processing to supplement the missing data, the accuracy of data processing is improved, the communication burden is reduced, and the data quality and reliability of the evaluation process are ensured; by establishing an adaptive notch filtering method to estimate and optimize the frequency parameters, a complete evaluation system is constructed based on electrical parameter calculation and power control calculation, the station operation efficiency is improved, and the grid-connected perception capability of the power grid to the new energy station is improved, and the scientificity and efficiency of the evaluation method are guaranteed. The present invention achieves better results in terms of data processing efficiency, communication burden and grid-connected perception capability.

[0073] Example 2

[0074] Reference Figure 1 to Figure 3 , which is a second embodiment of the present invention, and provides a method for evaluating the grid-connected performance of a new energy station, comprising:

[0075] S1, preprocessing the original data;

[0076] In the embodiment of the present application, the preprocessing of the original data includes: correcting or deleting abnormal data caused by human factors by using a method of determining a threshold value;

[0077] Abnormal data caused by system reasons are corrected by using variable joint matching method and smoothing filtering method;

[0078] And interpolate the missing data in a specific period;

[0079] Preprocessing can improve the operation efficiency of stations and enhance the grid’s ability to perceive the connection of new energy stations to the grid.

[0080] S2, extracting and calculating the fundamental wave components of electrical parameters from the processed data;

[0081] In the embodiment of the present application, the extraction and calculation of the fundamental wave component of the electrical parameter includes: extracting the voltage fundamental wave positive sequence component by sequence quantity decomposition method, including the voltage positive sequence component, the voltage negative sequence component and the voltage zero sequence component;

[0082] Calculate the positive sequence active current based on the positive sequence component, including the calculation of active power and the extraction of the fundamental positive sequence component of voltage and current;

[0083] Calculate positive sequence reactive current based on sequence quantity, including reactive power calculation;

[0084] The fundamental wave component extraction and calculation provide a basis for subsequent power setting value control.

[0085] The voltage fundamental positive sequence component is expressed as:

[0086]

[0087] Where U1, U2 and U3 represent the positive sequence component, negative sequence component and zero sequence component of voltage respectively, a represents the operator, and U a , U b and U c Represent the voltages of phase A, phase B and phase C respectively;

[0088] The positive sequence active current calculation can be expressed as:

[0089]

[0090] Among them, I 1p represents the positive sequence active current, P1 represents the active power calculated based on the positive sequence component, P u1,cos Represents the voltage fundamental positive sequence active component, P i1,cos Indicates the fundamental positive sequence active component of current, Q u1,sin Indicates the voltage fundamental positive sequence reactive component, Q i1,sin Indicates the current fundamental positive sequence reactive component;

[0091] The positive sequence reactive current calculation can be expressed as:

[0092]

[0093] Among them, I 1Q represents the positive sequence reactive current, and Q1 represents the reactive power calculated based on the positive sequence component.

[0094] S3, using the extracted amount to calculate the power setting value control capability;

[0095] In the embodiment of the present application, the power setting value control capability calculation includes: calculating the maximum deviation of active power according to the phase difference between the voltage positive sequence component and the positive sequence active current;

[0096] Calculate the maximum deviation of reactive power based on the positive sequence component of the voltage fundamental wave;

[0097] Calculate response time based on setpoint control start and end times;

[0098] Evaluate the grid-connected performance of the station through calculation.

[0099] It should be noted that the frequency estimation value determination process includes:

[0100] When the frequency estimate does not meet the preset range requirements, the power setting value control capability calculation is returned, including:

[0101] Calculation of maximum deviation of active power:

[0102]

[0103] Among them, σ p Indicates the maximum deviation of active power, Indicates the phase difference between the positive sequence voltage component and the positive sequence active current, P m Indicates the active power setting target value;

[0104] Calculation of maximum reactive power deviation:

[0105]

[0106] Among them, σ Q Indicates the maximum deviation of reactive power, Q m Indicates reactive power setting target value;

[0107] Response time calculation:

[0108] t p =t p,1 -t p,2

[0109] Among them, t p Represents the response time, t p,1 Indicates the start time of set value control, t p,2 Indicates the end time of set value control;

[0110] The frequency estimation value is recalculated according to the calculation result until the frequency estimation value meets the preset maximum and minimum value range requirements.

[0111] S4, using the adaptive notch filter method to estimate the frequency parameters and determine whether they meet the requirements.

[0112] In the embodiment of the present application, the adaptive notch filtering method includes: using two coefficients for filtering control, and performing parameter configuration on the two coefficients;

[0113] The frequency estimation value is obtained by iterative calculation;

[0114] and comparing it with a preset range to determine whether the frequency estimate meets the requirement;

[0115] If the requirements are met, the operation is terminated; if the requirements are not met, the power setting value control capability calculation is returned.

[0116] It should be noted that the frequency parameters are estimated by the adaptive notch filter method to determine whether the frequency estimation value meets the requirements. If yes, the operation is terminated. Otherwise, the active power setting value is returned to control the control capability calculation until the frequency estimation value meets the requirements. The adaptive notch filter method (ANF) has two coefficient controls, and the filter formula is expressed as:

[0117]

[0118] Among them, d1 and d2 represent two filtering coefficients. represents the value of coefficient d1 after k calculations, γ represents the gain, and y k It represents the notch output value after k calculations, p k represents the sensitivity related to d1, r2 represents the pole radius determined by the coefficient d2, f represents the frequency estimate, and T represents the sampling period.

[0119] Furthermore, the present embodiment also provides a new energy station grid-connected performance evaluation system, including a data preprocessing module, a parameter extraction module, a power control module and a frequency evaluation module;

[0120] The data preprocessing module is used to analyze, organize, modify and edit the original data, perform threshold correction or system cause correction on abnormal data, and perform interpolation processing on missing data;

[0121] The parameter extraction module is used to extract the voltage fundamental positive sequence component, calculate the positive sequence active current and the positive sequence reactive current from the processed data;

[0122] The power control module is used to calculate the maximum deviation of active power, the maximum deviation of reactive power and the response time based on the extracted electrical parameters;

[0123] The frequency evaluation module is used to estimate the frequency parameters by using an adaptive notch filter method, and to determine whether the frequency estimation value meets the requirements. If it does not meet the requirements, it returns to the power control module for recalculation.

[0124] This embodiment also provides a computer device, which is suitable for the case of a new energy station grid-connected performance evaluation method, including a memory and a processor; the memory is used to store computer-executable instructions, and the processor is used to execute computer-executable instructions to implement the new energy station grid-connected performance evaluation method proposed in the above embodiment.

[0125] The computer device may be a terminal, and the computer device includes a processor, a memory, a communication interface, a display screen and an input device connected via a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be achieved through WIFI, an operator network, NFC (near field communication) or other technologies. The display screen of the computer device may be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device may be a touch layer covering the display screen, or a key, trackball or touchpad provided on the housing of the computer device, or an external keyboard, touchpad or mouse, etc.

[0126] This embodiment also provides a storage medium on which a computer program is stored. When the program is executed by a processor, the method for evaluating the grid-connected performance of a new energy station proposed in the above embodiment is implemented.

[0127] In summary, the new energy station grid-connected performance evaluation method provided by the present invention ensures the accuracy and reliability of the grid-connected performance evaluation and improves the evaluation efficiency by implementing the steps of raw data preprocessing, parameter extraction calculation, power control calculation and frequency evaluation; by adopting the variable joint matching method, smoothing filtering method, etc. to correct the abnormal data, and combining the interpolation processing to supplement the missing data, the accuracy of data processing is improved, the communication burden is reduced, and the data quality and reliability of the evaluation process are ensured; by establishing an adaptive notch filtering method to estimate and optimize the frequency parameters, a complete evaluation system is constructed based on electrical parameter calculation and power control calculation, the station operation efficiency is improved, and the grid-connected perception capability of the power grid to the new energy station is improved, and the scientificity and efficiency of the evaluation method are guaranteed. The present invention achieves better results in terms of data processing efficiency, communication burden and grid-connected perception capability.

[0128] Example 3

[0129] This is the third embodiment of the present invention. This embodiment provides a new energy station grid-connected performance evaluation method. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through economic benefit calculation and simulation experiments.

[0130] In order to verify the effectiveness of the method of the present invention, a new energy station was selected as the test object for simulation experiments. The installed capacity of the station is 100MW, and the sampling frequency is set to 1ms. The experiment designed a frequency change scenario: the system frequency remained unchanged at 50Hz during 0-0.8s, the frequency increased at a rate of 0.5Hz / s from 0.8s to 1.6s, the frequency remained unchanged at 50.4Hz from 1.6s to 2.4s, the frequency decreased at a rate of 0.25Hz / s from 2.4s to 3.6s, and remained unchanged at 50.1Hz after 3.6s.

[0131] In the data preprocessing stage, the method of the present invention is used to process the collected data. For the approximately 2% data loss caused by communication delay, cubic spline interpolation is used to supplement it; for the measurement noise caused by equipment jitter, a low-pass filter with a cutoff frequency of 0.1Hz is used for smoothing; for abnormal values ​​beyond the normal range, a judgment threshold of ±3σ is set to identify and eliminate them.

[0132] Subsequently, the sequence decomposition method is used to extract the voltage fundamental positive sequence component, and the sampling window is set to 20ms to calculate the positive sequence active current and reactive current. On this basis, the power setting value control capability is calculated, and the response dead zone is set to 0.2%. Finally, the adaptive notch filter method is used for frequency estimation, and the initial parameters are set to: θ = 0.95, λ = 0.98, γ = 0.01.

[0133] The test results are shown in the following table:

[0134]

[0135] The following conclusions can be drawn from the analysis of experimental data:

[0136] First, in terms of frequency estimation accuracy, the method of the present invention exhibits excellent tracking performance. During the entire test process, the frequency estimation error is always controlled within the range of ±2.1mHz. In particular, in the 0.8s-1.6s frequency rapid rise stage (change rate 0.5Hz / s) and 2.4s-3.6s frequency drop stage (change rate 0.25Hz / s), the estimated value can still accurately track the actual frequency change, which verifies the effectiveness of the adaptive notch filter algorithm.

[0137] Secondly, from the perspective of power response time, during the dynamic frequency change, the system response time is always kept within 85ms. Even at the two frequency mutation points of 0.8s and 2.4s, the response time does not increase significantly, indicating that the method of the present invention has good dynamic characteristics. This rapid response capability is of great significance for improving the grid-connected stability of new energy stations.

[0138] Finally, by comparing the square of the error between the frequency estimate and the actual frequency, it can be found that the error is always maintained at a low level. This shows that the evaluation method proposed in the present invention not only has high accuracy under steady-state conditions, but also can maintain stable estimation performance in dynamic processes, providing reliable frequency information support for the grid-connected control of new energy stations.

[0139] In summary, the simulation experiment verifies that the method of the present invention exhibits excellent estimation accuracy and response characteristics under the frequency dynamic change scenario, which fully meets the engineering requirements of the grid-connected performance evaluation of new energy stations.

[0140] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for evaluating the grid-connected performance of a new energy station, characterized in that: include, Preprocess the raw data; Extract and calculate the fundamental wave components of electrical parameters from the processed data; Utilize the extracted quantity to calculate the power setpoint control capability; Adaptive notch filtering is used to estimate the frequency parameters and determine whether they meet the requirements.

2. The method for evaluating the grid connection performance of a new energy station according to claim 1, characterized in that: The preprocessing of the original data includes: correcting or deleting abnormal data caused by human factors by using a method of judging a threshold value; Abnormal data caused by system reasons are corrected by using variable joint matching method and smoothing filtering method; And interpolate the missing data in a specific period; Preprocessing can improve the operation efficiency of stations and enhance the grid’s ability to perceive the connection of new energy stations to the grid.

3. The method for evaluating the grid connection performance of a new energy station according to claim 2, characterized in that: The electrical parameter fundamental wave component extraction and calculation includes: extracting the voltage fundamental wave positive sequence component by sequence quantity decomposition method, including voltage positive sequence component, voltage negative sequence component and voltage zero sequence component; Calculate the positive sequence active current based on the positive sequence component, including the calculation of active power and the extraction of the fundamental positive sequence component of voltage and current; Calculate positive sequence reactive current based on sequence quantity, including reactive power calculation; The fundamental wave component extraction and calculation provide a basis for subsequent power setting value control.

4. The method for evaluating the grid connection performance of a new energy station according to claim 3, characterized in that: The power setting value control capability calculation includes: calculating the maximum deviation of active power according to the phase difference between the voltage positive sequence component and the positive sequence active current; Calculate the maximum deviation of reactive power based on the positive sequence component of the voltage fundamental wave; Calculate response time based on setpoint control start and end times; Evaluate the grid-connected performance of the station through calculation.

5. The method for evaluating the grid connection performance of a new energy station according to claim 4, characterized in that: The adaptive notch filtering method comprises: using two coefficients for filtering control and performing parameter configuration on the two coefficients; The frequency estimation value is obtained by iterative calculation; and comparing it with a preset range to determine whether the frequency estimate meets the requirement; If the requirements are met, the operation is terminated; if the requirements are not met, the power setting value control capability calculation is returned.

6. The method for evaluating the grid connection performance of a new energy station according to claim 5, characterized in that: The coefficient iterative calculation process of the adaptive notch filter method includes: Iterative calculation is performed through the filtering formula: Among them, d1 and d2 represent two filtering coefficients. represents the value of coefficient d1 after k calculations, γ represents the gain, and y k It represents the notch output value after k calculations, p k represents the sensitivity related to d1, r2 represents the pole radius determined by the coefficient d2, f represents the frequency estimate, and T represents the sampling period; The notch output value y k The calculation is performed by decomposing the voltage fundamental positive sequence component into sequence quantities: Where U1, U2 and U3 represent the positive sequence component, negative sequence component and zero sequence component of voltage respectively, a represents the operator, and U a , U b and U c Represent the voltages of phase A, phase B and phase C respectively; Based on the calculation results, it is determined whether the frequency estimation value meets the requirements.

7. The method for evaluating the grid connection performance of a new energy station according to claim 6, characterized in that: The frequency estimation value determination process includes: When the frequency estimate does not meet the preset range requirements, the power setting value control capability calculation is returned, including: Calculation of maximum deviation of active power: Among them, σ p Indicates the maximum deviation of active power, Indicates the phase difference between the positive sequence voltage component and the positive sequence active current, P m Indicates the active power setting target value; Calculation of maximum reactive power deviation: Among them, σ Q Indicates the maximum deviation of reactive power, Q m Indicates reactive power setting target value; Response time calculation: t p =t p,1 -t p,2 Among them, t p Represents the response time, t p,1 Indicates the start time of set value control, t p,2 Indicates the end time of set value control; The frequency estimation value is recalculated according to the calculation result until the frequency estimation value meets the preset maximum and minimum value range requirements.

8. A new energy station grid-connected performance evaluation system, based on the new energy station grid-connected performance evaluation method according to any one of claims 1 to 7, characterized in that: It also includes a data preprocessing module, a parameter extraction module, a power control module and a frequency evaluation module; The data preprocessing module is used to analyze, organize, modify and edit the original data, perform threshold correction or system cause correction on abnormal data, and perform interpolation processing on missing data; The parameter extraction module is used to extract the voltage fundamental positive sequence component, calculate the positive sequence active current and the positive sequence reactive current from the processed data; The power control module is used to calculate the maximum deviation of active power, the maximum deviation of reactive power and the response time based on the extracted electrical parameters; The frequency evaluation module is used to estimate the frequency parameters by using an adaptive notch filter method, and to determine whether the frequency estimation value meets the requirements. If it does not meet the requirements, it returns to the power control module for recalculation.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the new energy station grid-connected performance evaluation method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the new energy station grid-connected performance evaluation method according to any one of claims 1 to 7 are implemented.

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